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Sample records for anopheles arabiensis diptera

  1. A Qualitative Evidence of the Breeding Sites of Anopheles arabiensis Patton (Diptera: Culicidae) in and Around Kassala Town, Eastern Sudan.

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    Hamza, Asma Mahmoud; El Rayah, El Amin

    2016-01-01

    Anopheles arabiensis Patton (Diptera: Culicidae) is considered the most efficient malaria vector in eastern Sudan. This study aims to characterize the breeding sites of An. arabiensis throughout the year in and around Kassala town, eastern Sudan. Diverse larval habitat types were visited and characterized based on the habitat type and chemical composition. Mosquito larvae were found in many diverse habitats. During the rainy season, rain pools and water bodies created by the seasonal Gash River serve as the main breeding sites. In the dry season, irrigation canals, seepage from water pipes, neglected wells, artificial containers, and man-made ditches serve as the main breeding sites. Breeding water showed a pH of 7.9 and a low concentration of the total dissolved salts. The results of this study may be considered in planning and implementing larval control programs in the area. PMID:27547039

  2. The spatial distribution of Anopheles gambiae sensu stricto and An. arabiensis (Diptera: Culicidae in Mali

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    N. Sogoba

    2007-05-01

    Full Text Available Variations in the biology and ecology and the high level of genetic polymorphism of malaria vectors in Africa highlight the value of mapping their spatial distribution to enhance successful implementation of integrated vector management. The objective of this study was to collate data on the relative frequencies of Anopheles gambiae s.s. and An. arabiensis mosquitoes in Mali, to assess their association with climate and environmental covariates, and to produce maps of their spatial distribution. Bayesian geostatistical logistic regression models were fitted to identify environmental determinants of the relative frequencies of An. gambiae s.s. and An. arabiensis species and to produce smooth maps of their geographical distribution. The frequency of An. arabiensis was positively associated with the normalized difference vegetation index, the soil water storage index, the maximum temperature and the distance to water bodies. It was negatively associated with the minimum temperature and rainfall. The predicted map suggests that, in West Africa, An. arabiensis is concentrated in the drier savannah areas, while An. gambiae s.s. prefers the southern savannah and land along the rivers, particularly the inner delta of Niger. Because the insecticide knockdown resistance (kdr gene is reported only in An. gambiae s.s. in Mali, the maps provide valuable information for vector control. They may also be useful for planning future implementation of malaria control by genetically manipulated mosquitoes.

  3. First report of Metarhizium anisopliae IP 46 pathogenicity in adult Anopheles gambiae s.s. and An. arabiensis (Diptera; Culicidae)

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    Mnyone, L.L.; Russell, T.L.; Lyimo, I.N.; Lwetoijera, D.W.; Kirby, M.J.; Luz, C.

    2009-01-01

    The entomopathogenic fungus Metarhizium anisopliae isolate IP 46, originating from a soil sample collected in 2001 in the Cerrado of Central Brazil, was tested for its ability to reduce the survival of adult male and female Anopheles gambiae s.s. and An. arabiensis mosquitoes. A 6-h exposure to the

  4. Survival of immature Anopheles arabiensis (Diptera: Culicidae in aquatic habitats in Mwea rice irrigation scheme, central Kenya

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    Jacob Benjamin

    2006-11-01

    Full Text Available Abstract Background The survivorship and distribution of Anopheles arabiensis larvae and pupae was examined in a rice agro-ecosystem in Mwea Irrigation Scheme, central Kenya, from August 2005 to April 2006, prior to implementation of larval control programme. Methods Horizontal life tables were constructed for immatures in semi-field condition. The time spent in the various immature stages was determined and survival established. Vertical life tables were obtained from five paddies sampled by standard dipping technique. Results Pre-adult developmental time for An. arabiensis in the trays in the experimental set up in the screen house was 11.85 days from eclosion to emergence. The mean duration of each instar stage was estimated to be 1.40 days for first instars, 2.90 days for second instars, 1.85 days for third instars, 3.80 days for fourth instars and 1.90 days for pupae. A total of 590 individuals emerged into adults, giving an overall survivorship from L1 to adult emergence of 69.4%. A total of 4,956 An. arabiensis immatures were collected in 1,400 dips throughout the sampling period. Of these, 55.9% were collected during the tillering stage, 42.5% during the transplanting period and 1.6% during the land preparation stage. There was a significant difference in the An. arabiensis larval densities among the five stages. Also there was significant variation in immature stage composition for each day's collection in each paddy. These results indicate that the survival of the immatures was higher in some paddies than others. The mortality rate during the transplanting was 99.9% and at tillering was 96.6%, while the overall mortality was 98.3%. Conclusion The survival of An. arabiensis immatures was better during the tillering stage of rice growth. Further the survival of immatures in rice fields is influenced by the rice agronomic activities including addition of nitrogenous fertilizers and pesticides. For effective integrated vector management

  5. Radiation-induced sterility for pupal and adult stages of the malaria moquito Anopheles arabiensis

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    Helinski, M.E.H.; Parker, A.G.; Knols, B.G.J.

    2006-01-01

    Background - In the context of the Sterile Insect Technique (SIT), radiation-induced sterility in the malaria mosquito Anopheles arabiensis Patton (Diptera: Culicidae) was studied. Male mosquitoes were exposed to gamma rays in the pupal or adult stage and dose-sterility curves were determined. Methods - Pupae were irradiated shortly before emergence (at 22-26 hrs of age), and adults

  6. Dynamics of immature stages of Anopheles arabiensis and other mosquito species (Diptera: Culicidae) in relation to rice cropping in a rice agro-ecosystem in Kenya.

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    Mwangangi, Joseph; Shililu, Josephat; Muturi, Ephantus; Gu, Weidong; Mbogo, Charles; Kabiru, Ephantus; Jacob, Benjamin; Githure, John; Novak, Robert

    2006-12-01

    We determined changes in species composition and densities of immature stages of Anopheles arabiensis mosquitoes in relation to rice growth cycle in order to generate data for developing larval control strategies in rice ecosystems. Experimental rice paddies (6.3m x 3.15m) exposed to natural colonization of mosquitoes were sampled weekly for two rice growing cycles between February 2004 and March 2005. Overall, 21,325 Anopheles larvae were collected, of which 91.9% were 1st and 2nd instars and 8.1% were 3rd and 4th instars. An. arabiensis was the predominant species (84.1%) with other species, An. pharoensis (13.5%), An. funestus (2.1%), An. coustani (0.3%), and An. maculipalpis (0.1%) accounting for only a small proportion of the anophelines collected. Culex quinquefasciatus (65.7%) was the predominant species among the non-anopheline species. Others species collected included: C. annulioris (9.9%), C. poicilipes (7.3%), C. tigripes (7.2%), C. duttoni (0.6%), Aedes aegypti (5.3%), Ae. cumminsii (3.5%), and Ae. vittatus (0.7%). The densities of the major anopheline species were closely related to rice stage and condition of the rice field. An. arabiensis, the predominant species, was most abundant over a three-week period after transplanting. Low densities of larvae were collected during the late vegetative, reproductive, and ripening phases of rice. An increase in larval density ten days post-transplanting was found to correlate with the application of fertilizer (sulphate of ammonia). Culicine and aedine species densities were significantly higher during the post-harvesting period. Our results suggest that the transplanting stage is favorable for the growth of immature stages of An. arabiensis and provides a narrow window for targeted larval intervention in rice. PMID:17249341

  7. Field investigation on the repellent activity of some aromatic plants by traditional means against Anopheles arabiensis and An. pharoensis (Diptera: Culicidae) around Koka, central Ethiopia.

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    Dugassa, Sisay; Medhin, Girmay; Balkew, Meshesha; Seyoum, Aklilu; Gebre-Michael, Teshome

    2009-10-01

    A study was undertaken to evaluate the impact of traditional application methods of mosquito repellent plants in the reduction of the human-vector contact of malaria vectors in central Ethiopia. The plants (Corymbia citriodora, Eucalyptus camaldulensis, Ocimum suave and Ocimum basilicum) were tested by thermal expulsion and direct burning on traditional stoves in the field against two important malaria vectors in Ethiopia (Anopheles arabiensis and An. pharoensis). A Latin-square design was applied for randomly assigning the treatment plants and control to experimental houses over different nights. The percentage repellency of each candidate plant by both application methods was estimated from the catches of mosquitoes in the treatment and control houses. On direct burning of the plants, O. basilicum showed the highest percentage repellency (73.11%, Pcitriodora on the other hand gave the highest repellency (72.87%, Pcitriodora exhibited the highest repellency (78.69%, Pcitriodora gave the highest repellency (72.9%, P65%) against the house-entry and biting of two important malaria vectors in Ethiopia, and thus have a potential to be used at least as supplements to other control methods. However, feasibility and actual impact on disease transmission need to be known on these and other potentially useful plants. PMID:19539591

  8. Efficacy of three insect repellents against the malaria vector Anopheles arabiensis.

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    Govere, J; Durrheim, D N; Baker, L; Hunt, R; Coetzee, M

    2000-12-01

    Three commercial repellents marketed in South Africa: Bio-Skincare (BSC, oils of coconut, jojoba, rapeseed and vitamin E), Mosiguard towelletes with 0.574 g quwenling (p-menthane-3,8-diol, PMD) and the standard deet (15% diethyl-3-methylbenzamide, Tabard lotion), were compared against a laboratory colony of the mosquito Anopheles arabiensis Patton (Diptera: Culicidae), the predominant malaria vector in South Africa. Human forearms were treated with 1.2 g BSC, 0.8 g PMD towelette or 0.5 g deet and exposed to 200 hungry An. arabiensis females for 1 min, at intervals of 1-6 h post-treatment. Tests were conducted by three adult male volunteers (aged 30-45 years, crossover controlled test design for 3 consecutive days), using their left arm for treatment and right arm for untreated control. Biting rates averaged 39-52 bites/min on untreated arms. All three repellents provided complete protection against An. arabiensis for up to 3-4 h post-application; deet and PMD gave 90-100% protection up to 5-6h, but BSC declined to only 52% protection 6h post-treatment. These results are interpreted to show that all three repellent products give satisfactory levels of personal protection against An. arabiensis for 4-5 h, justifying further evaluation in the field. PMID:11129710

  9. Comparative susceptibility to Plasmodium falciparum of the molecular forms M and S of Anopheles gambiae and Anopheles arabiensis

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    Boudin Christian

    2011-09-01

    Full Text Available Abstract Background The different taxa belonging to Anopheles gambiae complex display phenotypic differences that may impact their contribution to malaria transmission. More specifically, their susceptibility to infection, resulting from a co-evolution between parasite and vector, might be different. The aim of this study was to compare the susceptibility of M and S molecular forms of Anopheles gambiae and Anopheles arabiensis to infection by Plasmodium falciparum. Methods F3 progenies of Anopheles gambiae s.l. collected in Senegal were infected, using direct membrane feeding, with P. falciparum gametocyte-containing blood sampled on volunteer patients. The presence of oocysts was determined by light microscopy after 7 days, and the presence of sporozoite by ELISA after 14 days. Mosquito species and molecular forms were identified by PCR. Results The oocyst rate was significantly higher in the molecular S form (79.07% than in the M form (57.81%, Fisher's exact test p Anopheles arabiensis (55.38%, Fisher's exact test vs. S group p An. gambiae S form (1.72 ± 0.26 than in the An. gambiae M form (0.64 ± 0.04, p An. arabiensis group (0.58 ± 0.04, vs. S group, p Anopheles arabiensis 50.85%, Fisher's exact test vs. S group p Conclusion Infected in the same experimental conditions, the molecular form S of An. gambiae is more susceptible to infection by P. falciparum than the molecular form M of An. gambiae and An. arabiensis.

  10. Population genetic structure of Anopheles arabiensis and Anopheles gambiae in a malaria endemic region of southern Tanzania

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    K.R. Ng'habi; B.G.J. Knols; Y. Lee; H.M. Ferguson; G.C. Lanzaro

    2011-01-01

    Background: Genetic diversity is a key factor that enables adaptation and persistence of natural populations towards environmental conditions. It is influenced by the interaction of a natural population's dynamics and the environment it inhabits. Anopheles gambiae s.s. and Anopheles arabiensis are t

  11. Radiation-induced sterility for pupal and adult stages of the malaria mosquito Anopheles arabiensis

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    Knols Bart GJ

    2006-05-01

    Full Text Available Abstract Background In the context of the Sterile Insect Technique (SIT, radiation-induced sterility in the malaria mosquito Anopheles arabiensis Patton (Diptera: Culicidae was studied. Male mosquitoes were exposed to gamma rays in the pupal or adult stage and dose-sterility curves were determined. Methods Pupae were irradiated shortly before emergence (at 22–26 hrs of age, and adults Results Irradiation of pupae, for all doses tested, had no effect on adult emergence. Survival curves of males irradiated as pupae or adults were similar or even slightly higher than non-irradiated males. Overall, adults appeared to be slightly more susceptible to irradiation, although no significant differences for individual doses were observed. In the pupal stage, a significant negative correlation was found between insemination and dose, but the correlation-coefficient was associated with less than 25% of the total variation. A review of the literature indicated that An. arabiensis is more radiation resistant than other anopheline mosquitoes. Conclusion The optimal dose for male insects to be released in an SIT programme depends on their level of sterility and competitiveness. The use of semi-sterilizing doses to produce more competitive insects is discussed. The most convenient developmental stage for mosquito irradiation on a mass-scale are pupae, but pupal irradiation resulted in a lower insemination rate at the highest dose compared to adult irradiation. On the basis of this study, a suitable dose range that includes semi-sterilizing doses is identified to initiate competitiveness experiments for males irradiated at both developmental stages.

  12. The genetics of inviability and male sterility in hybrids between Anopheles gambiae and An. arabiensis.

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    Slotman, M; Della Torre, A; Powell, J R

    2004-05-01

    Male hybrids between Anopheles gambiae and An. arabiensis suffer from hybrid sterility, and inviability effects are sometimes present as well. We examined the genetic basis of these reproductive barriers between the two species, using 21 microsatellite markers. Generally, recessive inviability effects were found on the X chromosome of gambiae that are incompatible with at least one factor on each arabiensis autosome. Inviability is complete when the gambiae and arabiensis inviability factors are hemi- or homozygous. Using a QTL mapping approach, regions that contribute to male hybrid sterility were also identified. The X chromosome has a disproportionately large effect on male hybrid sterility. Additionally, several moderate-to-large autosomal QTL were found in both species. The effect of these autosomal QTL is contingent upon the presence of an X chromosome from the other species. Substantial regions of the autosomes do not contribute markedly to male hybrid sterility. Finally, no evidence for epistatic interactions between conspecific sterility loci was found.

  13. Participation of irradiated Anopheles arabiensis males in swarms following field release in Sudan

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    Ageep, Tellal B; Damiens, David; Alsharif, Bashir; Ahmed, Ayman; Salih, Elwaleed HO; Ahmed, Fayez TA; Diabaté, Abdoulaye; Lees, Rosemary S.; Gilles, Jeremie RL; El Sayed, Badria B

    2014-01-01

    Background The success of the sterile insect technique (SIT) depends the release of large numbers of sterile males, which are able to compete for mates with the wild male population within the target area. Unfortunately, the processes of colonisation, mass production and irradiation may reduce the competitiveness of sterile males through genetic selection, loss of natural traits and somatic damage. In this context, the capacity of released sterile Anopheles arabiensis males to survive, disper...

  14. Identification of field caught Anopheles gambiae s.s. and Anopheles arabiensis by TaqMan single nucleotide polymorphism genotyping

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    Bayoh Nabie M

    2007-02-01

    Full Text Available Abstract Background Identification of Anopheles gambiae s.s. and Anopheles arabiensis from field-collected Anopheles gambiae s.l. is often necessary in basic and applied research, and in operational control programmes. The currently accepted method involves use of standard polymerase chain reaction amplification of ribosomal DNA (rDNA from the 3' 28S to 5' intergenic spacer region of the genome, and visual confirmation of amplicons of predicted size on agarose gels, after electrophoresis. This report describes development and evaluation of an automated, quantitative PCR method based upon TaqMan™ single nucleotide polymorphism (SNP genotyping. Methods Standard PCR, and TaqMan SNP genotyping with newly designed primers and fluorophore-labeled probes hybridizing to sequences of complementary rDNA specific for either An. gambiae s.s. or An. arabiensis, were conducted in three experiments involving field-collected An. gambiae s.l. from western Kenya, and defined laboratory strains. DNA extraction was from a single leg, sonicated for five minutes in buffer in wells of 96-well PCR plates. Results TaqMan SNP genotyping showed a reaction success rate, sensitivity, and species specificity comparable to that of standard PCR. In an extensive field study, only 29 of 3,041 (0.95% were determined to be hybrids by TaqMan (i.e., having rDNA sequences from both species, however, all but one were An. arabiensis by standard PCR, suggesting an acceptably low (ca. 1% error rate for TaqMan genotyping in mistakenly identifying species hybrids. Conclusion TaqMan SNP genotyping proved to be a sensitive and rapid method for identification of An. gambiae s.l. and An. arabiensis, with a high success rate, specific results, and congruence with the standard PCR method.

  15. Biochemical basis of permethrin resistance in Anopheles arabiensis from Lower Moshi, north-eastern Tanzania

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    Oxborough Richard M

    2010-07-01

    Full Text Available Abstract Background Development of resistance to different classes of insecticides is a potential threat to malaria control. With the increasing coverage of long-lasting insecticide-treated nets in Tanzania, the continued monitoring of resistance in vector populations is crucial. It may facilitate the development of novel strategies to prevent or minimize the spread of resistance. In this study, metabolic-based mechanisms conferring permethrin (pyrethroid resistance were investigated in Anopheles arabiensis of Lower Moshi, Kilimanjaro region of north-eastern Tanzania. Methods WHO susceptibility test kits were used to detect resistance to permethrin in An. arabiensis. The levels and mechanisms of permethrin resistance were determined using CDC bottle bioassays and microplate (biochemical assays. In bottle bioassays, piperonyl butoxide (PBO and s,s,s-tributyl phosphorotrithioate (DEF were used as synergists to inhibit mixed function oxidases and non-specific esterases respectively. Biochemical assays were carried out in individual mosquitoes to detect any increase in the activity of enzymes typically involved in insecticide metabolism (mixed function oxidases, α- and β-esterases. Results Anopheles arabiensis from the study area was found to be partially resistant to permethrin, giving only 87% mortality in WHO test kits. Resistance ratios at KT50 and KT95 were 4.0 and 4.3 respectively. The permethrin resistance was partially synergized by DEF and by PBO when these were mixed with permethrin in bottle bioassays and was fully synergized when DEF and PBO were used together. The levels of oxidase and β-esterase activity were significantly higher in An. arabiensis from Lower Moshi than in the laboratory susceptible strain. There was no difference in α-esterase activity between the two strains. Conclusion Elevated levels of mixed function oxidases and β-esterases play a role in detoxification of permethrin in the resistant An. arabiensis population

  16. Islands and Stepping-Stones: Comparative Population Structure of Anopheles gambiae sensu stricto and Anopheles arabiensis in Tanzania and Implications for the Spread of Insecticide Resistance.

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    Deodatus Maliti; Hilary Ranson; Stephen Magesa; William Kisinza; Juma Mcha; Khamis Haji; Gerald Killeen; David Weetman

    2014-01-01

    Population genetic structures of the two major malaria vectors Anopheles gambiae s.s. and An. arabiensis, differ markedly across Sub-Saharan Africa, which could reflect differences in historical demographies or in contemporary gene flow. Elucidation of the degree and cause of population structure is important for predicting the spread of genetic traits such as insecticide resistance genes or artificially engineered genes. Here the population genetics of An. gambiae s.s. and An. arabiensis in ...

  17. Abiotic and biotic factors associated with the presence of Anopheles arabiensis immatures and their abundance in naturally occurring and man-made aquatic habitats

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    Gouagna Louis

    2012-07-01

    Full Text Available Abstract Background Anopheles arabiensis (Diptera: Culicidae is a potential malaria vector commonly present at low altitudes in remote areas in Reunion Island. Little attention has been paid to the environmental conditions driving larval development and abundance patterns in potential habitats. Two field surveys were designed to determine whether factors that discriminate between aquatic habitats with and without An. arabiensis larvae also drive larval abundance, comparatively in man-made and naturally occurring habitats. Methods In an initial preliminary survey, a representative sample of aquatic habitats that would be amenable to an intensive long-term study were selected and divided into positive and negative sites based on the presence or absence of Anopheles arabiensis larvae. Subsequently, a second survey was prompted to gain a better understanding of biotic and abiotic drivers of larval abundance, comparatively in man-made and naturally occurring habitats in the two studied locations. In both surveys, weekly sampling was performed to record mosquito species composition and larval density within individual habitats, as well as in situ biological characteristics and physico-chemical properties. Results Whilst virtually any stagnant water body could be a potential breeding ground for An. arabiensis, habitats occupied by their immatures had different structural and biological characteristics when compared to those where larvae were absent. Larval occurrence seemed to be influenced by flow velocity, macrofauna diversity and predation pressure. Interestingly, the relative abundance of larvae in man-made habitats (average: 0.55 larvae per dip, 95%CI [0.3–0.7] was significantly lower than that recorded in naturally occurring ones (0.74, 95%CI [0.5–0.8]. Such differences may be accounted for in part by varying pressures that could be linked to a specific habitat. Conclusions If the larval ecology of An. arabiensis is in general very complex

  18. Molecular typing of bacteria of the genus Asaia in malaria vector Anopheles arabiensis Patton, 1905

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    S. Epis

    2012-08-01

    Full Text Available The acetic acid bacterium Asaia spp. was successfully detected in Anopheles arabiensis Patton, 1905, one of the major vector of human malaria in Sub-Saharan Africa. A collection of 45 Asaia isolates in cellfree media was established from 20 individuals collected from the field in Burkina Faso. 16S rRNA universal polymerase chain reaction (PCR and specific qPCR, for the detection of Asaia spp. were performed in order to reveal the presence of different bacterial taxa associated with this insect. The isolates were typed by internal transcribed spacer-PCR, BOX-PCR, and randomly amplified polymorphic DNA-PCR, proved the presence of different Asaia in A. arabiensis.

  19. Comparative efficacies of permethrin-, deltamethrin- and alpha-cypermethrin-treated nets, against Anopheles arabiensis and Culex quinquefasciatus in northern Tanzania.

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    Mosha, F W; Lyimo, I N; Oxborough, R M; Matowo, J; Malima, R; Feston, E; Mndeme, R; Tenu, F; Kulkarni, M; Maxwell, C A; Magesa, S M; Rowland, M W

    2008-06-01

    Mosquito nets treated with permethrin, deltamethrin or alpha-cypermethrin at 25 mg/m(2) were evaluated in experimental huts in an area of rice irrigation near Moshi, in northern Tanzania. The nets were deliberately holed to resemble worn nets. The nets treated with permethrin offered the highest personal protection against Anopheles arabiensis (61.6% reduction in fed mosquitoes) and Culex quinquefasciatus (25.0%). Deltamethrin and alpha-cypermethrin provided lower personal protection against An. arabiensis (46.4% and 45.6%, respectively) and no such protection against Cx. quinquefasciatus. Permethrin performed poorly in terms of mosquito mortality, however, killing only 15.2% of the An. arabiensis and 9.2% of the Cx. quinquefasciatus exposed to the nets treated with this pyrethroid (after correcting for control mortality). The alpha-cypermethrin and deltamethrin performed marginally better, with respective mortalities of 32.8% and 33.0% for An. arabiensis and 19.4% and 18.9% for Cx quinquefasciatus. The poor killing effect of permethrin was confirmed in a second trial where a commercial, long-lasting insecticidal net based on this pyrethroid (Olyset) produced low mortalities in both An. arabiensis (11.8%) and Cx. quinquefasciatus (3.6%). Anopheles arabiensis survivors collected from the verandahs of the experimental huts and tested on 0.75%-permethrin and 0.05%-deltamethrin papers, in World Health Organization susceptibility kits, showed mortalities of 96% and 100%, respectively. The continued use of permethrin-treated nets is recommended for personal protection against An. arabiensis. In control programmes that aim to interrupt transmission of pathogens by mosquitoes and/or manage pyrethroid resistance in such vectors, a combination of a pyrethroid and another insecticide with greater killing effect should be considered.

  20. Larvicidal effects of Chinaberry (Melia azederach) powder on Anopheles arabiensis in Ethiopia

    Science.gov (United States)

    2011-01-01

    Background Synthetic insecticides are employed in the widely-used currently favored malaria control techniques involving indoor residual spraying and treated bednets. These methods have repeatedly proven to be highly effective at reducing malaria incidence and prevalence. However, rapidly emerging mosquito resistance to the chemicals and logistical problems in transporting supplies to remote locations threaten the long-term sustainability of these techniques. Chinaberry (Melia azederach) extracts have been shown to be effective growth-inhibiting larvicides against several insects. Because several active chemicals in the trees' seeds have insecticidal properties, the emergence of resistance is unlikely. Here, we investigate the feasibility of Chinaberry as a locally available, low-cost sustainable insecticide that can aid in controlling malaria. Chinaberry fruits were collected from Asendabo, Ethiopia. The seeds were removed from the fruits, dried and crushed into a powder. From developmental habitats in the same village, Anopheles arabiensis larvae were collected and placed into laboratory containers. Chinaberry seed powder was added to the larval containers at three treatment levels: 5 g m-2, 10 g m-2 and 20 g m-2, with 100 individual larvae in each treatment level and a control. The containers were monitored daily and larvae, pupae and adult mosquitoes were counted. This experimental procedure was replicated three times. Results Chinaberry seed powder caused an inhibition of emergence of 93% at the 5 g m-2 treatment level, and 100% inhibition of emergence at the two higher treatment levels. The Chinaberry had a highly statistically significant larvicidal effect at all treatment levels (χ2 = 184, 184, and 155 for 5 g m-2, 10 g m-2 and 20 g m-2, respectively; p larvicide against the major African malaria vector An. arabiensis. The seed could provide a sustainable additional malaria vector control tool that can be used where the tree is abundant and where An

  1. Screening of selected ethnomedicinal plants from South Africa for larvicidal activity against the mosquito Anopheles arabiensis

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    Maharaj Rajendra

    2012-09-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito larvicidal properties. Methods Extracts of a selection of plant taxa sourced in South Africa were tested for larvicidal properties in an applicable assay. Thirty 3rd instar Anopheles arabiensis larvae were exposed to various extract types (dichloromethane, dichloromethane/methanol (1:1, methanol and purified water of each species investigated. Mortality was evaluated relative to the positive control Temephos (Mostop; Agrivo, an effective emulsifiable concentrate larvicide. Results Preliminary screening of crude extracts revealed substantial variation in toxicity with 24 of the 381 samples displaying 100% larval mortality within the seven day exposure period. Four of the high activity plants were selected and subjected to bioassay guided fractionation. The results of the testing of the fractions generated identified one fraction of the plant, Toddalia asiatica as being very potent against the An. arabiensis larvae. Conclusion The present study has successfully identified a plant with superior larvicidal activity at both the crude and semi pure fractions generated through bio-assay guided fractionation. These results have initiated further research into isolating the active compound and developing a malaria vector control tool.

  2. Additional selection for insecticide resistance in urban malaria vectors: DDT resistance in Anopheles arabiensis from Bobo-Dioulasso, Burkina Faso.

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    Christopher M Jones

    Full Text Available In the city of Bobo-Dioulasso in Burkina Faso, Anopheles arabiensis has superseded Anopheles gambiae s.s. as the major malaria vector and the larvae are found in highly polluted habitats normally considered unsuitable for Anopheles mosquitoes. Here we show that An. gambiae s.l. adults emerging from a highly polluted site in the city centre (Dioulassoba have a high prevalence of DDT resistance (percentage mortality after exposure to diagnostic dose=65.8% in the dry season and 70.4% in the rainy season, respectively. An investigation into the mechanisms responsible found an unexpectedly high frequency of the 1014S kdr mutation (allele frequency=0.4, which is found at very low frequencies in An. arabiensis in the surrounding rural areas, and an increase in transcript levels of several detoxification genes, notably from the glutathione transferase and cytochrome P450 gene families. A number of ABC transporter genes were also expressed at elevated levels in the DDT resistant An. arabiensis. Unplanned urbanisation provides numerous breeding grounds for mosquitoes. The finding that Anopheles mosquitoes adapted to these urban breeding sites have a high prevalence of insecticide resistance has important implications for our understanding of the selective forces responsible for the rapid spread of insecticide resistant populations of malaria vectors in Africa.

  3. Status of insecticide susceptibility in Anopheles arabiensis from Mwea rice irrigation scheme, Central Kenya

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    Vulule John M

    2006-06-01

    Full Text Available Abstract Background Control of the Anopheline mosquito vectors of malaria by use of insecticides has been shown to impact on both morbidity and mortality due to this disease. Evidence of insecticide resistance in different settings necessitates surveillance studies to allow prompt detection of resistance should it arise and thus enable its management. Possible resistance by Anopheles arabiensis mosquitoes from Mwea rice irrigation scheme in Central Kenya to insecticides in the four classes of insecticides approved by WHO for indoor residual spraying was investigated. Methods Susceptibility to DDT (an organochlorine, fenitrothion (an organophosphate, bendiocarb (a carbamate, lambdacyhalothrin and permethrin (both pyrethroids was tested using standard WHO diagnostic bioassay kits. Bioassays were performed on non-blood fed mosquitoes one- to three-day old. Knockdown was recorded every 10 min and mortality 24 h post-exposure was noted. Results Mortality 24 h post-exposure was 100% for all insecticides except for lambdacyhalothrin, which averaged 99.46%. Knockdown rates at 10 min intervals were not significantly different between the Mwea population and the susceptible KISUMU strain of Anopheles gambiae sensu stricto control. The KDT50 and KDT95 values for the Mwea population were either lower than those for the control or higher by factors of no more than 2 for most comparisons and compared well with those of An. gambiae sensu lato categorized as susceptible in other studies. Conclusion These results suggest that the Mwea population of An. arabiensis is susceptible to all the insecticides tested. This implies that vector control measures employing any of these insecticides would not be hampered by resistance.

  4. Participation of irradiated Anopheles arabiensis males in swarms following field release in Sudan

    International Nuclear Information System (INIS)

    BACKGROUND: The success of the SIT depends on the; release of large numbers of sterile males, which are able to; compete for mates with the wild male population within the; target area. The processes of colonisation, mass production; and irradiation may reduce the competitiveness of sterile; males through genetic selection, loss of natural traits and; somatic damage. In this context, the capacity of released; sterile Anopheles arabiensis males to survive, disperse and; participate in swarms occurring at varying distances from; the release site was studied using mark-release-recapture; techniques.; METHODS: In order to assess their participation in; swarms, irradiated and marked laboratory-reared male; mosquitoes were released 50, 100 or 200 m from the; known site of a large swarm on three consecutive nights.; Males were collected from this large swarm on subsequent; nights. Over the three days a total of 8,100 males were released.; Mean distance travelled (MDT), daily probability of; survival and estimated population size were calculated; from the recapture data. An effect of male age at the time; of release on these parameters was observed.; RESULTS: Five per cent of the males released over three; days were recaptured. In two-, three- and four-day-old; males, MDT was 118, 178 and 170 m, and the daily survival; probability 0.95, 0.90 and 0.75, respectively. From the; recapture data on the first day following each release, the; Lincoln index gives an estimation of 32,546 males in the; natural population.; DISCUSSION: Sterile An. arabiensis males released into; the field were able to find and participate in existing; swarms, and possibly even initiate swarms. The survival; probability decreased with the age of male on release but; the swarm participation and the distance travelled by older; males seemed higher than for younger males. The inclusion; of a pre-release period may thus be beneficial to male competitiveness; and increase the attractiveness of adult sexing

  5. Water quality and immatures of the M and S forms of Anopheles gambiae s.s. and An. arabiensis in a Malian village

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    Touré Yeya T

    2006-04-01

    Full Text Available Abstract Introduction The associations between the immatures of Anopheles gambiae s.s. (Diptera: Culicidae, its M and S forms, and Anopheles arabiensis among and within larval breeding habitats in Banambani, Mali were investigated under varying conditions of water quality and rainfall. The intent was to elucidate on niche partitioning of these taxa. Methods Immatures of An. arabiensis, An. gambiae s.s., and its M and S forms were sampled every alternate day for a month in mid-rainy season from three sampling sites in each of the larval breeding habitats (rock pools, swamp, and puddles. Water quality was characterized by alkalinity, conductivity, dissolved oxygen (D.O., nitrate, orthophosphate, pH, temperature, total dissolved solids (TDS, and turbidity. A type 3 analysis of the GENMOD model was used to examine the associations between the proportional frequencies of young (first and second instar larvae and old (third and fourth instar larvae and pupae or total immatures of species or forms among sampling sites within and among larval breeding habitats during a category of rainfall as influenced by water quality. Results Of the 4,174 immatures sampled, 1,300 were molecularly identified to species and forms. Significant association between the proportional frequencies of young larvae of An. arabiensis, An. gambiae s.s., its M and S forms was found among sampling sites within habitats but not among larval breeding habitats. The proportional frequencies of young larvae of M and S forms varied daily perhaps due to recruitment, mortality, and dispersal within habitats. Conductivity and TDS had significant effects when the proportional frequencies of young larvae of M and S forms among sampling sites within habitats were significantly associated. Alkalinity, D.O., orthophosphate, pH, nitrate, temperature and turbidity had no effects on niche partitioning of species and forms among sampling sites within habitats. Rainfall did not affect the frequencies

  6. Thermal limits of wild and laboratory strains of two African malaria vector species, Anopheles arabiensis and Anopheles funestus

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    Lyons Candice L

    2012-07-01

    Full Text Available Abstract Background Malaria affects large parts of the developing world and is responsible for almost 800,000 deaths annually. As climates change, concerns have arisen as to how this vector-borne disease will be impacted by changing rainfall patterns and warming temperatures. Despite the importance and controversy surrounding the impact of climate change on the potential spread of this disease, little information exists on the tolerances of several of the vector species themselves. Methods Using a ramping protocol (to assess critical thermal limits - CT and plunge protocol (to assess lethal temperature limits - LT information on the thermal tolerance of two of Africa’s important malaria vectors, Anopheles arabiensis and Anopheles funestus was collected. The effects of age, thermal acclimation treatment, sex and strain (laboratory versus wild adults were investigated for CT determinations for each species. The effects of age and sex for adults and life stage (larvae, pupae, adults were investigated for LT determinations. Results In both species, females are more tolerant to low and high temperatures than males; larvae and pupae have higher upper lethal limits than do adults. Thermal acclimation of adults has large effects in some instances but small effects in others. Younger adults tend to be more tolerant of low or high temperatures than older age groups. Long-standing laboratory colonies are sufficiently similar in thermal tolerance to field-collected animals to provide reasonable surrogates when making inferences about wild population responses. Differences between these two vectors in their thermal tolerances, especially in larvae and pupae, are plausibly a consequence of different habitat utilization. Conclusions Limited plasticity is characteristic of the adults of these vector species relative to others examined to date, suggesting limited scope for within-generation change in thermal tolerance. These findings and the greater tolerance

  7. Islands and stepping-stones: comparative population structure of Anopheles gambiae sensu stricto and Anopheles arabiensis in Tanzania and implications for the spread of insecticide resistance.

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    Deodatus Maliti

    Full Text Available Population genetic structures of the two major malaria vectors Anopheles gambiae s.s. and An. arabiensis, differ markedly across Sub-Saharan Africa, which could reflect differences in historical demographies or in contemporary gene flow. Elucidation of the degree and cause of population structure is important for predicting the spread of genetic traits such as insecticide resistance genes or artificially engineered genes. Here the population genetics of An. gambiae s.s. and An. arabiensis in the central, eastern and island regions of Tanzania were compared. Microsatellite markers were screened in 33 collections of female An. gambiae s.l., originating from 22 geographical locations, four of which were sampled in two or three years between 2008 and 2010. An. gambiae were sampled from six sites, An. arabiensis from 14 sites, and both species from two sites, with an additional colonised insectary sample of each species. Frequencies of the knock-down resistance (kdr alleles 1014S and 1014F were also determined. An. gambiae exhibited relatively high genetic differentiation (average pairwise FST = 0.131, significant even between nearby samples, but without clear geographical patterning. In contrast, An. arabiensis exhibited limited differentiation (average FST = 0.015, but strong isolation-by-distance (Mantel test r = 0.46, p = 0.0008. Most time-series samples of An. arabiensis were homogeneous, suggesting general temporal stability of the genetic structure. An. gambiae populations from Dar es Salaam and Bagamoyo were found to have high frequencies of kdr 1014S (around 70%, with almost 50% homozygote but was at much lower frequency on Unguja Island, with no. An. gambiae population genetic differentiation was consistent with an island model of genetic structuring with highly restricted gene flow, contrary to An. arabiensis which was consistent with a stepping-stone model of extensive, but geographically-restricted gene flow.

  8. Repellent efficacy of DEET, MyggA, neem (Azedirachta indica) oil and chinaberry (Melia azedarach) oil against Anopheles arabiensis, the principal malaria vector in Ethiopia

    OpenAIRE

    Abiy, Ephrem; Gebre-Michael, Teshome; Balkew, Meshesha; Medhin, Girmay

    2015-01-01

    Background In Ethiopia, Anopheles arabiensis is the main vector responsible for the transmission of malaria in the country and its control mainly involves application of indoor residual spraying (IRS) and use of insecticide-treated bed nets (ITNs). Objective Although the role of repellents for reducing man-vector contact is documented in the literature, the response of An. arabiensis to repellents was not previously evaluated under field conditions in Ethiopia. Method The trial was conducted ...

  9. Larvicidal efficacy of Ethiopian ethnomedicinal plant Juniperus procera essential oil against Afrotropical malaria vector Anopheles arabiensis (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Kaliyaperumal Karunamoorthi; Askual Girmay; Samuel Fekadu

    2014-01-01

    Objective: To screen the essential oil of Juniperus procera (J. procera) (Cupressaceae) for larvicidal activity against late third instar larvae of Anopheles arabiensis (An. arabiensis) Patton, the principle malaria vector in Ethiopia.Methods:the laboratory and semi-field conditions by adopting the World Health Organization standard protocols. The larval mortality was observed for 24 h of post exposure.Results:The essential oil of J. procera has demonstrated varying degrees of larvicidal activity The essential oil of J. procera was evaluated against the larvae of An. arabiensis under against An. arabiensis. The LC50 and LC90 values of J. procera were 14.42 and 24.65 mg/L, respectively under the laboratory conditions, and from this data, a Chi-square value 6.662 was observed to be significant at the P=0.05 level. However, under the semi-field conditions the LC50 and LC90 values of J. procera were 24.51 and 34.21 mg/L, respectively and a Chi-square value 4.615 was significant at the P=0.05 level. The observations clearly showed that larval mortality rate is completely time and dose-dependent as compared with the control.Conclusions:This investigation indicates that J. procera could serve as a potential larvicidal agent against insect vector of diseases, particularly An. arabiensis. However further studies are strongly recommended for the identification of the chemical constituents and the mode of action towards the rational design of alternative promising insecticidal agents in the near future.

  10. The Genetic Basis of Host Preference and Resting Behavior in the Major African Malaria Vector, Anopheles arabiensis

    Science.gov (United States)

    Main, Bradley J; Lee, Yoosook; Ferguson, Heather M.; Kreppel, Katharina S.; Kihonda, Anicet; Govella, Nicodem J.; Collier, Travis C.; Cornel, Anthony J.; Eskin, Eleazar; Kang, Eun Yong; Nieman, Catelyn C.; Weakley, Allison M.; Lanzaro, Gregory C.

    2016-01-01

    Malaria transmission is dependent on the propensity of Anopheles mosquitoes to bite humans (anthropophily) instead of other dead end hosts. Recent increases in the usage of Long Lasting Insecticide Treated Nets (LLINs) in Africa have been associated with reductions in highly anthropophilic and endophilic vectors such as Anopheles gambiae s.s., leaving species with a broader host range, such as Anopheles arabiensis, as the most prominent remaining source of transmission in many settings. An. arabiensis appears to be more of a generalist in terms of its host choice and resting behavior, which may be due to phenotypic plasticity and/or segregating allelic variation. To investigate the genetic basis of host choice and resting behavior in An. arabiensis we sequenced the genomes of 23 human-fed and 25 cattle-fed mosquitoes collected both in-doors and out-doors in the Kilombero Valley, Tanzania. We identified a total of 4,820,851 SNPs, which were used to conduct the first genome-wide estimates of “SNP heritability” for host choice and resting behavior in this species. A genetic component was detected for host choice (human vs cow fed; permuted P = 0.002), but there was no evidence of a genetic component for resting behavior (indoors versus outside; permuted P = 0.465). A principal component analysis (PCA) segregated individuals based on genomic variation into three groups which were characterized by differences at the 2Rb and/or 3Ra paracentromeric chromosome inversions. There was a non-random distribution of cattle-fed mosquitoes between the PCA clusters, suggesting that alleles linked to the 2Rb and/or 3Ra inversions may influence host choice. Using a novel inversion genotyping assay, we detected a significant enrichment of the standard arrangement (non-inverted) of 3Ra among cattle-fed mosquitoes (N = 129) versus all non-cattle-fed individuals (N = 234; χ2, p = 0.007). Thus, tracking the frequency of the 3Ra in An. arabiensis populations may be of use to infer

  11. The effects of genetic manipulation, dieldrin treatment and irradiation on the mating competitiveness of male Anopheles arabiensis in field cages

    OpenAIRE

    Yamada, Hanano; Vreysen, Marc JB; Gilles, Jeremie RL; Munhenga, Givemore; Damiens, David D.

    2014-01-01

    Background To enable the release of only sterile male Anopheles arabiensis mosquitoes for the sterile insect technique, the genetic background of a wild-type strain was modified to create a genetic sexing strain ANO IPCL1 that was based on a dieldrin resistance mutation. Secondly, the eggs of ANO IPCL1 require treatment with dieldrin to allow complete elimination of female L1 larvae from the production line. Finally, male mosquito pupae need to be treated with an irradiation dose of 75 Gy for...

  12. Efficacy of leaves extract of Calotropis procera Ait. (Asclepiadaceae) in controlling Anopheles arabiensis and Culex quinquefasciatus mosquitoes.

    Science.gov (United States)

    Elimam, Abdalla M; Elmalik, Khitma H; Ali, Faysal S

    2009-10-01

    The present study aimed to investigate, the larvicidal, adult emergence inhibition and oviposition deterrent activity of aqueous leaves extract of Calotropis procera against Anopheles arabiensis and Culex quinquefasciatus as natural mosquito larvicide. The larvicidal activity was monitored against 2nd, 3rd and 4th instar larvae of each mosquito species 24 h post-treatment. Adult emergence inhibition activity was tested by exposing 3rd instar larvae of each mosquito species to different concentrations of extracts (200, 400, 600, 800 and 1000 ppm for An. arabiensis and 100, 200, 300, 400, 500 and 600 ppm for Cx. quinquefasciatus). Probit analysis was used to analyze data from bioassay experiments. The oviposition deterrent activity was tested by using three different concentrations of extracts (1000, 500 and 200 for An. arabiensis, and 1000, 500 and 100 for Cx. quinquefasciatus) that caused high, moderate and low larval mortality in the larvicidal experiment against 3rd instar larvae. It was found that, LC50-LC90 values calculated were 273.53-783.43, 366.44-1018.59 and 454.99-1224.62 ppm for 2nd, 3rd and 4th larval instars, respectively, of An. arabiensis and 187.93-433.51, 218.27-538.27 and 264.85-769.13 ppm for 2nd, 3rd and 4th larval instars, respectively, of Cx. quinquefasciatus. Fifty percent of adult emergence inhibition (EI50) was shown at 277.90 and 183.65 ppm for An. arabiensis and Cx. quinquefasciatus, respectively. The pupal stage was not affected till a concentration of 5000 ppm. The extract showed oviposition deterrence and effective repellence against both mosquito species at different concentrations, with the observation on that maximal eggs were laid in low concentration of extract. These results suggest that the leaves extract of C. procera possess remarkable larvicidal, adult emergence inhibitor, repellent and oviposition deterrent effect against both An. arabiensis and Cx. quinquefasciatus, and might be used as natural biocides for mosquito

  13. The influence of late-stage pupal irradiation and increased irradiated:un-irradiated male ratio on mating competitiveness of the malaria mosquito Anopheles arabiensis Patton

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2009-01-01

    Competitiveness of released males in genetic control programmes is of critical importance. In this paper, we explored two scenarios to compensate for the loss of mating competitiveness after pupal stage irradiation in males of the malaria mosquito Anopheles arabiensis. First, competition experiments

  14. Mating competitiveness of male Anopheles arabiensis mosquitoes irradiated with a partially or fully sterilizing dose in small and large laboratory cages

    NARCIS (Netherlands)

    Helinski, M.; Knols, B.G.J.

    2008-01-01

    Male mating competitiveness is a crucial parameter in many genetic control programs including the sterile insect technique (SIT). We evaluated competitiveness of male Anopheles arabiensis Patton as a function of three experimental variables: (1) small or large cages for mating, (2) the effects of ei

  15. Detection of the East and West African kdr mutation in Anopheles gambiae and Anopheles arabiensis from Uganda using a new assay based on FRET/Melt Curve analysis

    Directory of Open Access Journals (Sweden)

    Backeljau Thierry

    2006-02-01

    Full Text Available Abstract Background Appropriate monitoring of vector resistance to insecticides is an integral component of planning and evaluation of insecticide use in malaria control programmes. The malaria vectors Anopheles gambiae s.s. and Anopheles arabiensis have developed resistance to pyrethroid insecticides as a result of a mechanism conferring reduced nervous system sensitivity, better known as knockdown resistance (kdr. In An. gambiae s.s. and An. arabiensis, two different substitutions in the para-type sodium channel, a L1014F substitution common in West Africa and a L1014S replacement found in Kenya, are linked with kdr. Two different allele-specific polymerase chain reactions (AS-PCR are needed to detect these known kdr mutations. However, these AS-PCR assays rely on a single nucleotide polymorphism mismatch, which can result in unreliable results. Methods Here, a new assay for the detection of knockdown resistance in An. gambiae s.s. and An. arabiensis based on Fluorescence Resonance Energy Transfer/Melt Curve analysis (FRET/MCA is presented and compared with the existing assays. Results The new FRET/MCA method has the important advantage of detecting both kdr alleles in one assay. Moreover, results show that the FRET/MCA is more reliable and more sensitive than the existing AS-PCR assays and is able to detect new genotypes. By using this technique, the presence of the East African kdr mutation (L1014S is shown for the first time in An. arabiensis specimens from Uganda. In addition, a new kdr genotype is reported in An. gambiae s.s. from Uganda, where four An. gambiae s.s. mosquitoes possess both, the West (L1014F and East (L1014S African kdr allele, simultaneously. Conclusion The presence of both kdr mutations in the same geographical region shows the necessity of a reliable assay that enables to detect both mutations in one single assay. Hence, this new assay based on FRET/MCA will improve the screening of the kdr frequencies in An. gambiae s

  16. Microsporidium Infecting Anopheles supepictus (Diptera: Culicidae Larvae

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    Seyed-Mohammad Omrani

    2016-01-01

    Full Text Available Background: Microsporidia are known to infect a wide variety of animals including mosquitoes (Diptera: Cu­licidae. In a recent study on the mosquito fauna of Chahar Mahal and Bakhtiari Province, at the central western part of Iran, a few larvae of Anopheles superpictus were infected with a microsporidium-resembled microorganism. Cur­rent investigation deals with the identification of the responsible microorganism at the genus level.Methods: Fresh infected larvae were collected from the field. After determining the species identity they were dis­sected to extract their infective contents. Wet preparations were checked for general appearance and the size of the pathogenic microorganism. Fixed preparations were stained with Geimsa and Ryan-Blue modified Trichrome tech­niques to visualize further morphological characters. The obtained light microscopy data were used in the identifica­tion process.Results: The infected larvae were bulged by a whitish material filling the involved segments corresponding to a microsporidium infection. Bottle-shaped semioval spores ranged 4.33±0.19×2.67±0.12 and 4.18±0.43×2.45±0.33 micron in wet and fixed preparations, respectively. They were mostly arranged in globular structures comprised of 8 spores. These data was in favor of a species from the genus Parathelohania in the family Ambliosporidae.Conclusion: This is the first report of a microsporidium infection in An. superpictus. The causative agent is diag­nosed as a member of the genus Parathelohania. Further identification down to the species level needs to determine its ultrastructural characteristics and the comparative analysis of ss rRNA sequence data. It is also necessary to un­derstand the detail of the components of the transmission cycle.

  17. A resting box for outdoor sampling of adult Anopheles arabiensis in rice irrigation schemes of lower Moshi, northern Tanzania

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    Msangi Shandala

    2009-04-01

    Full Text Available Abstract Background Malaria vector sampling is the best method for understanding the vector dynamics and infectivity; thus, disease transmission seasonality can be established. There is a need to protecting humans involved in the sampling of disease vectors during surveillance or in control programmes. In this study, human landing catch, two cow odour baited resting boxes and an unbaited resting box were evaluated as vector sampling tools in an area with a high proportion of Anopheles arabiensis, as the major malaria vector. Methods Three resting boxes were evaluated against human landing catch. Two were baited with cow odour, while the third was unbaited. The inner parts of the boxes were covered with black cloth materials. Experiments were arranged in latin-square design. Boxes were set in the evening and left undisturbed; mosquitoes were collected at 06:00 am the next morning, while human landing catch was done overnight. Results A total of 9,558 An. arabiensis mosquitoes were collected. 17.5% (N = 1668 were collected in resting box baited with cow body odour, 42.5% (N = 4060 in resting box baited with cow urine, 15.1% (N = 1444 in unbaited resting box and 24.9% (N = 2386 were collected by human landing catch technique. In analysis, the house positions had no effect on the density of mosquitoes caught (DF = 3, F = 0.753, P = 0.387; the sampling technique had significant impact on the caught mosquitoes densities (DF = 3, F 37. 944, P Conclusion Odour-baited resting boxes have shown the possibility of replacing the existing traditional method (human landing catch for sampling malaria vectors in areas with a high proportion of An. arabiensis as malaria vectors. Further evaluations of fermented urine and longevity of the urine odour still need to be investigated.

  18. Identification and expression profiling of putative odorant-binding proteins in the malaria mosquitoes, Anopheles gambiae and A.arabiensis

    Institute of Scientific and Technical Information of China (English)

    LI Zhengxi; Jing-Jiang ZHOU; SHEN Zuorui; Lin FIELD

    2004-01-01

    Olfaction plays a major role in host-seeking behaviour of mosquitoes. An informatics-based genome-wide analysis of odorant-binding protein (OBP) homologues is undertaken,and 32 putative OBP genes in total in the whole genome sequences of Anopheles gambiae are identified. Tissue-specific expression patterns of all A. gambiae OBP candidates are determined by semi-quantitative Reverse Transcription (RT)-PCR using mosquito actin gene as internal expression control standard. The results showed that 20 OBP candidates had strong expression in mosquito olfactory tissues (female antennae), which indicate that OBPs may play an important role in regulating mosquito olfactory behaviours. Species-specific expression patterns of all putative anopheline OBPs are also studied in two of the most important malaria vectors in A. gambiae complex, i.e.A. gambiae and A. arabiensis, which found 12 of the putative OBP genes examined displayed species-differential expression patterns. The cumulative relative expression intensity of the OBPs in A. arabiensis antennae was higher than that in A. gambiae (the ratio is 1441.45:1314.12), which might be due to their different host preference behaviour. While A.gambiae is a highly anthropophilic mosquito, A. arabiensis is more opportunistic (varying from anthropophilic to zoophilic). So the latter should need more OBPs to support its host selection preference. Identification of mosquito OBPs and verification of their tissue- and species-specific expression patterns represent the first step towards further molecular analysis of mosquito olfactory mechanism, such as recombinant expression and ligand identification.

  19. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    Directory of Open Access Journals (Sweden)

    Folb Peter I

    2010-10-01

    Full Text Available Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic, that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodium opulifolium was found to be 97% as effective as DEET after 2 mins, time lag studies revealed a substantial reduction in efficacy (to 30% within two hours. Conclusions None of the plant extracts investigated exhibited residual repellencies >60% after three hours.

  20. Cannibalism and predation among larvae of the Anopheles gambiae complex

    NARCIS (Netherlands)

    Koenraadt, C.J.M.; Takken, W.

    2003-01-01

    Among the aquatic developmental stages of the Anopheles gambiae complex (Diptera: Culicidae), both inter- and intra-specific interactions influence the resulting densities of adult mosquito populations. For three members of the complex, An. arabiensis Patton, An. quadriannulatus (Theobald) and An. g

  1. Malaria in Kakuma refugee camp, Turkana, Kenya: facilitation of Anopheles arabiensis vector populations by installed water distribution and catchment systems

    Directory of Open Access Journals (Sweden)

    Cetron Martin S

    2011-06-01

    Full Text Available Abstract Background Malaria is a major health concern for displaced persons occupying refugee camps in sub-Saharan Africa, yet there is little information on the incidence of infection and nature of transmission in these settings. Kakuma Refugee Camp, located in a dry area of north-western Kenya, has hosted ca. 60,000 to 90,000 refugees since 1992, primarily from Sudan and Somalia. The purpose of this study was to investigate malaria prevalence and attack rate and sources of Anopheles vectors in Kakuma refugee camp, in 2005-2006, after a malaria epidemic was observed by staff at camp clinics. Methods Malaria prevalence and attack rate was estimated from cases of fever presenting to camp clinics and the hospital in August 2005, using rapid diagnostic tests and microscopy of blood smears. Larval habitats of vectors were sampled and mapped. Houses were sampled for adult vectors using the pyrethrum knockdown spray method, and mapped. Vectors were identified to species level and their infection with Plasmodium falciparum determined. Results Prevalence of febrile illness with P. falciparum was highest among the 5 to 17 year olds (62.4% while malaria attack rate was highest among the two to 4 year olds (5.2/1,000/day. Infected individuals were spatially concentrated in three of the 11 residential zones of the camp. The indoor densities of Anopheles arabiensis, the sole malaria vector, were similar during the wet and dry seasons, but were distributed in an aggregated fashion and predominantly in the same zones where malaria attack rates were high. Larval habitats and larval populations were also concentrated in these zones. Larval habitats were man-made pits of water associated with tap-stands installed as the water delivery system to residents with year round availability in the camp. Three percent of A. arabiensis adult females were infected with P. falciparum sporozoites in the rainy season. Conclusions Malaria in Kakuma refugee camp was due mainly

  2. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    OpenAIRE

    Malcolm Colin A; El-Motasim Waleed M; Hassan Mo'awia M; Helinski Michelle EH; Knols Bart GJ; El-Sayed Badria

    2008-01-01

    Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosqui...

  3. Evaluation of selected South African ethnomedicinal plants as mosquito repellents against the Anopheles arabiensis mosquito in a rodent model

    OpenAIRE

    Folb Peter I; Bhagwandin Niresh; Newmarch Marion; Crouch Neil R; Maharaj Vinesh; Maharaj Rajendra; Pillay Pamisha; Gayaram Reshma

    2010-01-01

    Abstract Background This study was initiated to establish whether any South African ethnomedicinal plants (indigenous or exotic), that have been reported to be used traditionally to repel or kill mosquitoes, exhibit effective mosquito repellent properties. Methods Extracts of a selection of South African taxa were tested for repellency properties in an applicable mosquito feeding-probing assay using unfed female Anopheles arabiensis. Results Although a water extract of the roots of Chenopodiu...

  4. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    OpenAIRE

    Malcolm Colin A; Benedict Mark Q; Knols Bart GJ; Hassan M'oawia M; Cox Jonathan; Ageep Tellal B; Babiker Ahmed; El Sayed Badria B

    2009-01-01

    Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM) that may include the sterile insect technique (SIT). To support the planning and implementation of future AW-IPM activities, larval surveys were...

  5. Antimosquito properties of 2-substituted phenyl/benzylamino-6-(4-chlorophenyl)-5-methoxycarbonyl-4-methyl-3,6-dihydropyrimidin--ium chlorides against Anopheles arabiensis.

    Science.gov (United States)

    Narayanaswamy, Venugopala K; Gleiser, Raquel M; Chalannavar, Raju K; Odhav, Bharti

    2014-03-01

    Eight novel dihydropyrimidine analogs named DHPM1-DHPM8 was synthesized in their hydrochloride salt form using one pot synthesis between methyl 2-chloro-4-(4-chlorophenyl)-6-methyl-1,4-dihydropyrimidine-5-carboxylate and substituted arylamines in isopropanol. The antimosquito effect of the test compounds were assessed against the adult mosquito Anopheles arabiensis. For adulticidal properties the test compounds were sprayed onto ceramic tiles and screened using the cone bio-assay method. The larvicidal activity was tested by monitoring larval mortality daily and up to 3 days of exposure. Repellency properties were tested in a feeding-probe assay using unfed female Anopheles arabiensis. Compounds DHPM1, DHPM4, DHPM5 and DHPM6 exerted larval mortality equivalent to temephos (trade name Abate, a commercial larvicidal compound). Compounds DHPM1 to DHPM5 repelled or knocked down 92 to 98% of mosquitoes exposed to rodent skin treated with the compounds. None of the compounds showed any significant activity against the adult mosquito Anopheles arabiensis. PMID:24506684

  6. Evaluation of Endod (Phytolacca dodecandra: Phytolaccaceae) as a Larvicide Against Anopheles arabiensis, the Principal Vector of Malaria in Ethiopia.

    Science.gov (United States)

    Getachew, Dejene; Balkew, Meshesha; Gebre-Michael, Teshome

    2016-06-01

    Malaria control methods rely mostly on adult mosquito control using insecticide-treated nets and indoor residual spraying with insecticides. Plants such as endod (Phytolacca dodecandra) can potentially be used for the control of mosquito larvae as a supplement to adult control methods. Following the discovery of endod, a molluscicide plant, more than 5 decades ago in Ethiopia, subsequent studies have shown that its potency can further be increased by simple procedures such as aging endod berry powder in water. This study was conducted to evaluate the killing effect of fresh and aged endod solution against 4th-stage larvae of Anopheles arabiensis. Laboratory-reared An. arabiensis larvae exposed to different concentrations of endod preparation using distilled or spring water had 50% lethal concentration (LC50)  =  49.6 ppm and 90% lethal concentration (LC90)  =  234 ppm for fresh and LC50  =  36.4 ppm and LC90  =  115.7 ppm for the aged endod solution in distilled water against the laboratory population. Against field-collected larvae of the same species, aged preparations in habitat water resulted in higher LC50 (472.7 ppm) and LC90 (691 ppm) values, with only a slight improvement over fresh preparations in habitat water (LC50  =  456.2 ppm; LC90  =  896.1 ppm). In general, although aged preparations of endod required lower concentrations than fresh to kill at least 90% of the larvae, these concentrations were much higher (12-70×) than that required for schistosome-transmitting snails. PMID:27280350

  7. Use of carbon-13 as a population marker for Anopheles arabiensis in a sterile insect technique (SIT context

    Directory of Open Access Journals (Sweden)

    Knols Bart GJ

    2006-01-01

    Full Text Available Abstract Background Monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the Sterile Insect Technique (SIT. Of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. Suitable ones include dye marking, genetic marking and chemical marking. Methods The feasibility of using the stable isotope of carbon, 13C, as a potential chemical marker for Anopheles arabiensis was evaluated in the laboratory. Labeled-13C glucose was incorporated into the larval diet in a powder or liquid form. The contribution of adult sugar feeding to the total mosquito carbon pool and the metabolically active carbon pool was determined by tracing the decline of the enrichment of the adult male mosquito as it switched from a labeled larval diet to an unlabeled adult diet. This decline in the adult was monitored by destructive sampling of the whole mosquito and analyzed using isotope ratio mass spectrometry. Results A two-pool model was used to describe the decline of the 13C-enrichment of adult mosquitoes. The proportion of the total adult carbon pool derived from the adult sugar diet over the life span of mosquitoes was determined and the ratio of structural carbon, with a low turnover rate to metabolically active non-structural carbon was assessed. The uptake and turnover of sugar in the metabolically active fraction suggests that after 3 days >70% of the active fraction carbon is derived from sugar feeding (increasing to >90% by day 7, indicating the high resource demand of male mosquitoes. Conclusion It was possible to "fix" the isotopic label in adult An. arabiensis and to detect the label at an appropriate concentration up to 21 days post-emergence. The optimum labeling treatment would cost around 250 US$ per million mosquitoes. Stable isotope marking may thus aid research on the fate of released insects besides other population

  8. Spatial and temporal distribution patterns of Anopheles arabiensis breeding sites in La Reunion Island - multi-year trend analysis of historical records from 1996-2009

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    Lempérière Guy

    2011-06-01

    Full Text Available Abstract Background An often confounding facet of the dynamics of malaria vectors is the aquatic larval habitat availability and suitable conditions under which they can thrive. Here, we investigated the impact of environmental factors on the temporal and spatial distribution of larval habitats of Anopheles arabiensis in different locations on La Reunion Island. Methods A retrospective examination was made from archival data which provided the complete enumeration of An. arabiensis breeding habitats in three distinct geographic zones - extending North-east, West and South of the island over 14 years, from January 1996 to December 2009. Data on the occurrence and the number of active larval habitats at each of a total of 4376 adjacent ellipsoid grid cells (216,506 square meters each were used (1 to provide the geographic extent of breeding site availability from year to year and (2 to analyze associations with prevailing environmental factors, habitat types, and locations. Results Anopheles arabiensis utilized a spectrum of man-made and natural aquatic habitats, most of which were concentrated primarily in the rock pools located in ravines and river fringes, and also in the large littoral marshes and within the irrigated agricultural zones. The numbers of breeding site per sampling grid differed significantly in different parts of the island. In contrast to an originally more widespread distribution across the island in the 1950s, detailed geographic analyses of the data obtained in the period extending from 1996-2009 showed an intriguing clustered distribution of active breeding sites in three discontinuous geographic zones, in which aquatic habitats availability fluctuates with the season and year. Seasonality in the prevalence of anopheles breeding sites suggests significant responsiveness to climatic factors. Conclusions The observed retreat of An. arabiensis distribution range to lower altitudinal zones (

  9. The Role of Oxidative Stress in the Longevity and Insecticide Resistance Phenotype of the Major Malaria Vectors Anopheles arabiensis and Anopheles funestus.

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    Shüné V Oliver

    Full Text Available Oxidative stress plays numerous biological roles, both functional and pathological. The role of oxidative stress in various epidemiologically relevant biological traits in Anopheles mosquitoes is not well established. In this study, the effects of oxidative stress on the longevity and insecticide resistance phenotype in the major malaria vector species An. arabiensis and An. funestus were examined. Responses to dietary copper sulphate and hydrogen peroxide were used as proxies for the oxidative stress phenotype by determining the effect of copper on longevity and hydrogen peroxide lethal dose. Glutathione peroxidase and catalase activities were determined colorimetrically. Oxidative burden was quantified as protein carbonyl content. Changes in insecticide resistance phenotype were monitored by WHO bioassay. Insecticide resistant individuals showed an increased capacity for coping with oxidative stress, mediated by increased glutathione peroxidase and catalase activity. This effect was observed in both species, as well as in laboratory strains and F1 individuals derived from wild-caught An. funestus mothers. Phenotypic capacity for coping with oxidative stress was greatest in strains with elevated Cytochrome P450 activity. Synergism of oxidative stress defence enzymes by dietary supplementation with haematin, 3-Amino-1, 2, 4-triazole and Sodium diethyldithiocarbamate significantly increased pyrethroid-induced mortality in An. arabiensis and An. funestus. It is therefore concluded that defence against oxidative stress underlies the augmentation of the insecticide resistance phenotype associated with multiple blood-feeding. This is because multiple blood-feeding ultimately leads to a reduction of oxidative stress in insecticide resistant females, and also reduces the oxidative burden induced by DDT and pyrethroids, by inducing increased glutathione peroxidase activity. This study highlights the importance of oxidative stress in the longevity and

  10. Mating competitiveness of sterile genetic sexing strain males (GAMA) under laboratory and semi-field conditions: Steps towards the use of the Sterile Insect Technique to control the major malaria vector Anopheles arabiensis in South Africa

    OpenAIRE

    Munhenga, Givemore; Brooke, Basil D; Gilles, Jeremie R. L.; Slabbert, Kobus; Kemp, Alan,; Dandalo, Leonard C.; Wood, Oliver R.; Lobb, Leanne N.; Govender, Danny; Renke, Marius; Koekemoer, Lizette L

    2016-01-01

    Background Anopheles arabiensis Patton is primarily responsible for malaria transmission in South Africa after successful suppression of other major vector species using indoor spraying of residual insecticides. Control of An. arabiensis using current insecticide based approaches is proving difficult owing to the development of insecticide resistance, and variable feeding and resting behaviours. The use of the sterile insect technique as an area-wide integrated pest management system to suppl...

  11. Ammonium sulphate fertiliser increases larval populations of Anopheles arabiensis and culicine mosquitoes in rice fields

    DEFF Research Database (Denmark)

    Mutero, C M; Ng'ang'a, P N; Wekoyela, P;

    2004-01-01

    Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block, and the fertili......Field experiments were conducted in central Kenya, to study the effect of ammonium sulphate fertiliser ((NH(4))(2)SO(4)) on mosquito larval populations in rice fields. The experiments used a complete randomised block design having four blocks with two experimental ponds per block......, and the fertiliser and control treatments allocated randomly among the ponds. Student's two-sample unpaired t-test was used to test for the significance of differences between the relative counts of larvae in fertiliser and control treatments. The results showed a significant overall increase in the larval...... populations of An. arabiensis (Pfertiliser. Significantly more fourth instar larvae of An. arabiensis were collected in fertiliser than control plots (Pfertiliser application had...

  12. A 15N stable isotope semen label to detect mating in the malaria mosquito Anopheles arabiensis Patton

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    Gludovacz Doris

    2008-07-01

    Full Text Available Abstract In previous studies it was determined that the stable isotope 13-carbon can be used as a semen label to detect mating events in the malaria mosquito Anopheles arabiensis. In this paper we describe the use of an additional stable isotope, 15-nitrogen (15N, for that same purpose. Both stable isotopes can be analysed simultaneously in a mass spectrometer, offering the possibility to detect both labels in one sample in order to study complex and difficult-to-detect mating events, such as multiple mating. 15N-glycine was added to larval rearing water and the target enrichment was 5 atom% 15N. Males from these trays were mated with unlabelled virgin females, and spiked spermathecae were analysed for isotopic composition after mating using mass spectrometry. Results showed that spermathecae positive for semen could be distinguished from uninseminated or control samples using the raw δ15N‰ values. The label persisted in spermathecae for up to 5 days after insemination, and males aged 10 days transferred similar amounts of label as males aged 4 days. There were no negative effects of the label on larval survival and male longevity. Enrichment of teneral mosquitoes after emergence was 4.85 ± 0.10 atom% 15N. A threshold value defined as 3 standard deviations above the mean of virgin (i.e. uninseminated spermathecae samples was successful in classifying a large proportion of samples correctly (i.e. on average 95%. We conclude that alongside 13C, 15N can be used to detect mating in Anopheles and the suitability of both labels is briefly discussed.

  13. A stable isotope dual-labelling approach to detect multiple insemination in un-irradiated and irradiated Anopheles arabiensis mosquitoes

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    Hood Rebecca C

    2008-04-01

    Full Text Available Abstract Background In the context of a Sterile Insect Technique programme, the occurrence of multiple insemination in the malaria mosquito Anopheles arabiensis Patton was studied using a novel labelling system with the stable isotopes 15N and 13C. The incidence of multiple insemination in the absence of radiation, and when males were irradiated in the pupal stage and competed against un-irradiated males were assessed. Males used in the experiments were labelled with either 15N or 13C and the label was applied to the larval rearing water. Males with either label and virgin females were caged at a 1:1:1 ratio. Males used in the radiation treatments were irradiated in the pupal stage with a partially or fully-sterilizing dose of 70 or 120 Gy, respectively. After mating, females were dissected and inseminated spermathecae analysed using mass spectrometry. Results The data indicate that about 25% of inseminated females had been inseminated multiply. The presence of irradiated males in the experiments did not affect the incidence of multiple insemination. In line with previous research, irradiated males were generally less competitive than un-irradiated males. Conclusion The implications of these findings for the Sterile Insect Technique are discussed, and further experiments recommended. The dual-labelling system used to determine paternity gave good results for 13C, however, for 15N it is recommended to increase the amount of label in future studies.

  14. The effect of larval nutritional deprivation on the life history and DDT resistance phenotype in laboratory strains of the malaria vector Anopheles arabiensis

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    Oliver Shüné V

    2013-02-01

    Full Text Available Abstract Background Anopheles arabiensis is a major malaria vector in Africa. It thrives in agricultural areas and has been associated with increased malaria incidence in areas under rice and maize cultivation. This effect may be due to increased adult size and abundance as a consequence of optimal larval nutrition. The aim of this study was to examine the effect of larval nutrition on the life history and expression of insecticide resistance in adults of laboratory reared An. arabiensis. Methods Larvae drawn from an insecticide susceptible An. arabiensis strain (SENN as well as a DDT-resistant strain (SENN-DDT were subjected to three fasting regimes: 1 mg of food per larva offered once per day, once every second day and once every third day. Control cohorts included larvae offered 1 mg food thrice per day. The rate of larval development was compared between matched cohorts from each strain as well as between fasted larvae and their respective controls. The expression of DDT resistance/tolerance in adults was compared between the starved cohorts and their controls by strain. Factors potentially affecting variation in DDT resistance/tolerance were examined including: adult body size (wing length, knock-down resistance (kdr status and levels of detoxification enzyme activity. Results and conclusion Anopheles arabiensis larval development is prolonged by nutrient deprivation and adults that eclose from starved larvae are smaller and less tolerant to DDT intoxication. This effect on DDT tolerance in adults is also associated with reduced detoxification enzyme activity. Conversely, well fed larvae develop comparatively quickly into large, more DDT tolerant (SENN or resistant (SENN-DDT adults. This is important in those instances where cereal farming is associated with increased An. arabiensis transmitted malaria incidence, because large adult females with high teneral reserves and decreased susceptibility to insecticide intoxication may also

  15. A field site for SIT control of Anopheles arabiensis in Northern State, Sudan: Analysis of historical data

    International Nuclear Information System (INIS)

    Full text: A field site suitable for SIT will have a single vector population that is isolated, unstructured, relatively small and low density. Disease transmission potential should be established and the cost benefit analysis of SIT should be favourable for the local community, nationally and regionally. Today's technology greatly facilitates the comprehensive and rapid assessment of these criteria, even if starting from zero, but an historical perspective is necessary. This paper researches data relevant to development of SIT for control of the malaria vector Anopheles arabiensis in Northern State, Sudan. The field site is primarily the Dongola Reach of the Nile extending from the Fourth Cataract to the Third Cataract. An. arabiensis is dependent on the river and the human population and is isolated by the desert. Northern State has an ancient history with important archaeological sites dating back to the Neolithic (4,500-3,500 BC). This has generated information on human health, settlement patterns and climate up to the medieval Christian and Islamic periods. The accounts of travellers and military historians provide data from the nineteenth century. In the early twentieth century there are detailed entomological and epidemiological records from the Wellcome Tropical Research Laboratories in Khartoum and later the Sudan Medical Service. Vector population studies increasingly rely on molecular genetic markers. These often have multiple interpretations that can be resolved by independent historical data that, for example, may infer the age of the current Northern State An. arabiensis population and how well isolated it has been. Entomological and hospital malaria records confirm the presence of A. arabiensis as early as 1906 and as far north as Wadi Halfa. It may have reached 150 km further north, at Ed Derr, in 1919 and certainly reached Asyut, 850 km into Egypt, in 1942. It was eradicated from Upper Egypt by 1945 and did not appear north of Ferka (250 km south

  16. Towards a sterile insect technique field release of Anopheles arabiensis mosquitoes in Sudan: Irradiation, transportation, and field cage experimentation

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2008-04-01

    Full Text Available Abstract Background The work described in this article forms part of a study to suppress a population of the malaria vector Anopheles arabiensis in Northern State, Sudan, with the Sterile Insect Technique. No data have previously been collected on the irradiation and transportation of anopheline mosquitoes in Africa, and the first series of attempts to do this in Sudan are reported here. In addition, experiments in a large field cage under near-natural conditions are described. Methods Mosquitoes were irradiated in Khartoum and transported as adults by air to the field site earmarked for future releases (400 km from the laboratory. The field cage was prepared for experiments by creating resting sites with favourable conditions. The mating and survival of (irradiated laboratory males and field-collected males was studied in the field cage, and two small-scale competition experiments were performed. Results Minor problems were experienced with the irradiation of insects, mostly associated with the absence of a rearing facility in close proximity to the irradiation source. The small-scale transportation of adult mosquitoes to the release site resulted in minimal mortality ( Conclusion It is concluded that although conditions are challenging, there are no major obstacles associated with the small-scale irradiation and transportation of insects in the current setting. The field cage is suitable for experiments and studies to test the competitiveness of irradiated males can be pursued. The scaling up of procedures to accommodate much larger numbers of insects needed for a release is the next challenge and recommendations to further implementation of this genetic control strategy are presented.

  17. Mathematical evaluation of community level impact of combining bed nets and indoor residual spraying upon malaria transmission in areas where the main vectors are Anopheles arabiensis mosquitoes

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    Okumu Fredros O

    2013-01-01

    Full Text Available Abstract Background Indoor residual insecticide spraying (IRS and long-lasting insecticide treated nets (LLINs are commonly used together even though evidence that such combinations confer greater protection against malaria than either method alone is inconsistent. Methods A deterministic model of mosquito life cycle processes was adapted to allow parameterization with results from experimental hut trials of various combinations of untreated nets or LLINs (Olyset®, PermaNet 2.0®, Icon Life® nets with IRS (pirimiphos methyl, lambda cyhalothrin, DDT, in a setting where vector populations are dominated by Anopheles arabiensis, so that community level impact upon malaria transmission at high coverage could be predicted. Results Intact untreated nets alone provide equivalent personal protection to all three LLINs. Relative to IRS plus untreated nets, community level protection is slightly higher when Olyset® or PermaNet 2.0® nets are added onto IRS with pirimiphos methyl or lambda cyhalothrin but not DDT, and when Icon Life® nets supplement any of the IRS insecticides. Adding IRS onto any net modestly enhances communal protection when pirimiphos methyl is sprayed, while spraying lambda cyhalothrin enhances protection for untreated nets but not LLINs. Addition of DDT reduces communal protection when added to LLINs. Conclusions Where transmission is mediated primarily by An. arabiensis, adding IRS to high LLIN coverage provides only modest incremental benefit (e.g. when an organophosphate like pirimiphos methyl is used, but can be redundant (e.g. when a pyrethroid like lambda cyhalothin is used or even regressive (e.g. when DDT is used for the IRS. Relative to IRS plus untreated nets, supplementing IRS with LLINs will only modestly improve community protection. Beyond the physical protection that intact nets provide, additional protection against transmission by An. arabiensis conferred by insecticides will be remarkably small, regardless of

  18. The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis.

    Science.gov (United States)

    Ibrahim, Sulaiman S; Riveron, Jacob M; Stott, Robert; Irving, Helen; Wondji, Charles S

    2016-01-01

    Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools.

  19. The cytochrome P450 CYP6P4 is responsible for the high pyrethroid resistance in knockdown resistance-free Anopheles arabiensis

    Science.gov (United States)

    Ibrahim, Sulaiman S.; Riveron, Jacob M.; Stott, Robert; Irving, Helen; Wondji, Charles S.

    2016-01-01

    Pyrethroid insecticides are the front line vector control tools used in bed nets to reduce malaria transmission and its burden. However, resistance in major vectors such as Anopheles arabiensis is posing a serious challenge to the success of malaria control. Herein, we elucidated the molecular and biochemical basis of pyrethroid resistance in a knockdown resistance-free Anopheles arabiensis population from Chad, Central Africa. Using heterologous expression of P450s in Escherichia coli coupled with metabolism assays we established that the over-expressed P450 CYP6P4, located in the major pyrethroid resistance (rp1) quantitative trait locus (QTL), is responsible for resistance to Type I and Type II pyrethroid insecticides, with the exception of deltamethrin, in correlation with field resistance profile. However, CYP6P4 exhibited no metabolic activity towards non-pyrethroid insecticides, including DDT, bendiocarb, propoxur and malathion. Combining fluorescent probes inhibition assays with molecular docking simulation, we established that CYP6P4 can bind deltamethrin but cannot metabolise it. This is possibly due to steric hindrance because of the large vdW radius of bromine atoms of the dihalovinyl group of deltamethrin which docks into the heme catalytic centre. The establishment of CYP6P4 as a partial pyrethroid resistance gene explained the observed field resistance to permethrin, and its inability to metabolise deltamethrin probably explained the high mortality from deltamethrin exposure in the field populations of this Sudano-Sahelian An. arabiensis. These findings describe the heterogeneity in resistance towards insecticides, even from the same class, highlighting the need to thoroughly understand the molecular basis of resistance before implementing resistance management/control tools. PMID:26548743

  20. A heteroskedastic error covariance matrix estimator using a first-order conditional autoregressive Markov simulation for deriving asympotical efficient estimates from ecological sampled Anopheles arabiensis aquatic habitat covariates

    Directory of Open Access Journals (Sweden)

    Githure John I

    2009-09-01

    Full Text Available Abstract Background Autoregressive regression coefficients for Anopheles arabiensis aquatic habitat models are usually assessed using global error techniques and are reported as error covariance matrices. A global statistic, however, will summarize error estimates from multiple habitat locations. This makes it difficult to identify where there are clusters of An. arabiensis aquatic habitats of acceptable prediction. It is therefore useful to conduct some form of spatial error analysis to detect clusters of An. arabiensis aquatic habitats based on uncertainty residuals from individual sampled habitats. In this research, a method of error estimation for spatial simulation models was demonstrated using autocorrelation indices and eigenfunction spatial filters to distinguish among the effects of parameter uncertainty on a stochastic simulation of ecological sampled Anopheles aquatic habitat covariates. A test for diagnostic checking error residuals in an An. arabiensis aquatic habitat model may enable intervention efforts targeting productive habitats clusters, based on larval/pupal productivity, by using the asymptotic distribution of parameter estimates from a residual autocovariance matrix. The models considered in this research extends a normal regression analysis previously considered in the literature. Methods Field and remote-sampled data were collected during July 2006 to December 2007 in Karima rice-village complex in Mwea, Kenya. SAS 9.1.4® was used to explore univariate statistics, correlations, distributions, and to generate global autocorrelation statistics from the ecological sampled datasets. A local autocorrelation index was also generated using spatial covariance parameters (i.e., Moran's Indices in a SAS/GIS® database. The Moran's statistic was decomposed into orthogonal and uncorrelated synthetic map pattern components using a Poisson model with a gamma-distributed mean (i.e. negative binomial regression. The eigenfunction

  1. Linking land cover and species distribution models to project potential ranges of malaria vectors: an example using Anopheles arabiensis in Sudan and Upper Egypt

    Directory of Open Access Journals (Sweden)

    Fuller Douglas O

    2012-08-01

    Full Text Available Abstract Background Anopheles arabiensis is a particularly opportunistic feeder and efficient vector of Plasmodium falciparum in Africa and may invade areas outside its normal range, including areas separated by expanses of barren desert. The purpose of this paper is to demonstrate how spatial models can project future irrigated cropland and potential, new suitable habitat for vectors such as An. arabiensis. Methods Two different but complementary spatial models were linked to demonstrate their synergy for assessing re-invasion potential of An. arabiensis into Upper Egypt as a function of irrigated cropland expansion by 2050. The first model (The Land Change Modeler was used to simulate changes in irrigated cropland using a Markov Chain approach, while the second model (MaxEnt uses species occurrence points, land cover and other environmental layers to project probability of species presence. Two basic change scenarios were analysed, one involving a more conservative business-as-usual (BAU assumption and second with a high probability of desert-to-cropland transition (Green Nile to assess a broad range of potential outcomes by 2050. Results The results reveal a difference of 82,000 sq km in potential An. arabiensis range between the BAU and Green Nile scenarios. The BAU scenario revealed a highly fragmented set of small, potential habitat patches separated by relatively large distances (maximum distance = 64.02 km, mean = 12.72 km, SD = 9.92, while the Green Nile scenario produced a landscape characterized by large patches separated by relatively shorter gaps (maximum distance = 49.38, km, mean = 4.51 km, SD = 7.89 that may be bridged by the vector. Conclusions This study provides a first demonstration of how land change and species distribution models may be linked to project potential changes in vector habitat distribution and invasion potential. While gaps between potential habitat patches remained large in the

  2. Spatial and temporal distribution of the malaria mosquito Anopheles arabiensis in northern Sudan: influence of environmental factors and implications for vector control

    Directory of Open Access Journals (Sweden)

    Malcolm Colin A

    2009-06-01

    Full Text Available Abstract Background Malaria is an important public health problem in northern Sudan, but little is known about the dynamics of its transmission. Given the characteristic low densities of Anopheles arabiensis and the difficult terrain in this area, future vector control strategies are likely to be based on area-wide integrated pest management (AW-IPM that may include the sterile insect technique (SIT. To support the planning and implementation of future AW-IPM activities, larval surveys were carried out to provide key data on spatial and seasonal dynamics of local vector populations. Methods Monthly cross-sectional larval surveys were carried out between March 2005 and May 2007 in two localities (Dongola and Merowe adjacent to the river Nile. A stratified random sampling strategy based on the use of Remote Sensing (RS, Geographical Information Systems (GIS and the Global Positioning System (GPS was used to select survey locations. Breeding sites were mapped using GPS and data on larval density and breeding site characteristics were recorded using handheld computers. Bivariate and multivariate logistic regression models were used to identify breeding site characteristics associated with increased risk of presence of larvae. Seasonal patterns in the proportion of breeding sites positive for larvae were compared visually to contemporaneous data on climate and river height. Results Of a total of 3,349 aquatic habitats sampled, 321 (9.6% contained An. arabiensis larvae. The frequency with which larvae were found varied markedly by habitat type. Although most positive sites were associated with temporary standing water around the margins of the main Nile channel, larvae were also found at brickworks and in areas of leaking pipes and canals – often far from the river. Close to the Nile channel, a distinct seasonal pattern in larval populations was evident and appeared to be linked to the rise and fall of the river level. These patterns were not

  3. Cladistic analysis of the subgenus Anopheles (Anopheles) Meigen (Diptera: Culicidae) based on morphological characters.

    Science.gov (United States)

    Collucci, Eliana; Sallum, Maria Anice Mureb

    2007-06-01

    In the present study, we used morphological characters to estimate phylogenetic relationships among members of the subgenus Anopheles Meigen. Phylogenetic analyses were carried out for 36 species of Anopheles (Anopheles). An. (Stethomyia) kompi Edwards, An. (Lophopodomyia) gilesi (Peryassú), Bironella hollandi Taylor, An. (Nyssorhynchus) oswaldoi (Peryassú) and An. (Cellia) maculatus Theobald were employed as outgroups. One hundred one characters of the external morphology of the adult male, adult female, fourth-instar larva, and pupa were scored and analyzed under the parsimony criterion in PAUP. Phylogenetic relationships among the series and several species informal groups of Anopheles (Anopheles) were hypothesized. The results suggest that Anopheles (Anopheles) is monophyletic. Additionally, most species groups included in the analysis were demonstrated to be monophyletic.

  4. Cladistic analysis of the subgenus Anopheles (Anopheles Meigen (Diptera: Culicidae based on morphological characters

    Directory of Open Access Journals (Sweden)

    Eliana Collucci

    2007-06-01

    Full Text Available In the present study, we used morphological characters to estimate phylogenetic relationships among members of the subgenus Anopheles Meigen. Phylogenetic analyses were carried out for 36 species of Anopheles (Anopheles. An. (Stethomyia kompi Edwards, An. (Lophopodomyia gilesi (Peryassú, Bironella hollandi Taylor, An. (Nyssorhynchus oswaldoi (Peryassú and An. (Cellia maculatus Theobald were employed as outgroups. One hundred one characters of the external morphology of the adult male, adult female, fourth-instar larva, and pupa were scored and analyzed under the parsimony criterion in PAUP. Phylogenetic relationships among the series and several species informal groups of Anopheles (Anopheles were hypothesized. The results suggest that Anopheles (Anopheles is monophyletic. Additionally, most species groups included in the analysis were demonstrated to be monophyletic.

  5. Larvicidal activities of chinaberry, neem and Bacillus thuringiensis israelensis (Bti) to an insecticide resistant population of Anopheles arabiensis from Tolay, Southwest Ethiopia

    Institute of Scientific and Technical Information of China (English)

    Assalif Demissew; Meshesha Balkew; Melaku Girma

    2016-01-01

    Objective: To elucidate the larvicidal potency of neem, chinaberry and Bacillus thur-ingiensis israelensis (Bti) to larvae of Anopheles arabiensis under semi-field condition and adult susceptibility/resistance to the conventionally used insecticides in Tolay, Southwestern Ethiopia. Methods: Wild collected 3rd and 4th stage larvae were exposed to neem, and chinaberry seed powder dissolved in water and Bti in artificial containers at three treatment levels:0.2, 0.1 and 0.05 g/m2 and controls were free of treatments. Larval and pupal mortalities were monitored daily and residual activities were determined. The experiments were replicated three times. The World Health Organization tube test for all classes of in-secticides was conducted on adult Anopheles arabiensis reared from field collected larvae and pupae. Data were analyzed using STATA software version 11. Results: In the first application, neem powder caused 88.9%, 87.9%and 79.4%larval and pupal mortality at 0.2, 0.1 and 0.05 g/m2 after 4.3, 6.0 and 5.7 days, respectively. The cor-responding killing effect of chinaberry was 80.3%, 62.1%and 30.3%after 7.0, 7.7 and 8.3 days respectively. Bti at all treatments killed 100%after 24 h except 2.7 days for 0.05 g/m2. Adult mosquitoes were susceptible only for fenitrothion and pirimiphos-methyl with 100%mortality while resistant to deltamethrin, alpha-cypermethrin, etofenprox and dichloro-diphenyl-tricgloroethane with only 9.0%, 3.0%, 5.1%and 2.0%mortalities respectively. Conclusions: Neem, chinaberry and Bti showed potent larvicidal and pupicidal activ-ities. However, in the area, high level of mosquito resistance to pyrethroids and dichloro-diphenyl-tricgloroethane was seen which will pose serious challenge to vector control in the future. Therefore, using integrated approach including these botanical larvicides is warranted to manage insecticide resistance.

  6. The Anopheles arabiensis genetic sexing strain ANO IPCL1 and its application potential for the sterile insect technique in integrated vector management programmes.

    Science.gov (United States)

    Yamada, Hanano; Vreysen, Marc J B; Bourtzis, Kostas; Tschirk, Wolfgang; Chadee, Dave D; Gilles, Jeremie R L

    2015-02-01

    The Anopheles arabiensis genetic sexing strain ANO IPCL1 was developed based on a dieldrin resistant mutation. The strain has been shown to be practical and reliable in terms of female elimination by dieldrin treatments at larval stages, but has provided some difficulties when treatments were applied at the egg stage. The high natural sterility of this strain has advantages and disadvantages in both mass rearing and the sterilization process. In addition, its recombination rate, although relatively low, poses a threat of strain deterioration if left unchecked in a mass-rearing setting. The males of the ANO IPCL1 have been shown to be equally competitive as lab-reared males of the wild-type Dongola strain, but competitiveness decreased by half when irradiated with 75 Gy—a dose conferring >98% sterility. More controversial issues surround the use of dieldrin—a highly persistent organochlorine that is known to bioaccumulate in the food chain. The prospective use of large volumes of dieldrin in a mass-rearing facility and the retention of its residues by the male mosquitoes makes the use of the strain in the context of the sterile insect technique against this vector highly questionable, and therefore its implementation at a large scale cannot be recommended. PMID:25438257

  7. Synthesis and antimosquito properties of 2,6-substituted benzo[d]thiazole and 2,4-substituted benzo[d]thiazole analogues against Anopheles arabiensis.

    Science.gov (United States)

    Venugopala, Katharigatta Narayanaswamy; Krishnappa, Manjula; Nayak, Susanta K; Subrahmanya, Bhat K; Vaderapura, Jayashankaragowda P; Chalannavar, Raju K; Gleiser, Raquel M; Odhav, Bharti

    2013-07-01

    A novel and efficient one pot synthesis was developed for 2,6-substituted-benzo[d]thiazole analogues 4a-k and 2,4-substituted-benzo[d]thiazole analogues 4l-pvia three component condensation reaction of substituted arylaldehyde, 2-amino-6-halo/4-methyl-benzo[d]thiazole and 2-naphthol or 6-hydroxyquinoline in presence of 10% w/v NaCl in water by microwave method. This method enabled for short reaction times, easy work-up and significant high yields. The title compound 4b was used for single crystal X-ray studies in order to understand its conformation and packing features. The title compounds 4a-p were screened for antimosquito properties such as repellency, insecticidal and larvicidal activity against Anopheles arabiensis by mosquito feeding-probing assay, cone bio-assay and standard WHO larvicidal assay, respectively. Among these analogous 4b, 4d and 4p exhibit the highest repellent activity comparable to the positive control DEET, and 4a and 4k knockdown most mosquitoes on repellent assays.

  8. Random amplified polymorphic DNA (RAPD) markers readily distinguish cryptic mosquito species (Diptera: Culicidae: Anopheles).

    Science.gov (United States)

    Wilkerson, R C; Parsons, T J; Albright, D G; Klein, T A; Braun, M J

    1993-01-01

    The usefulness of random amplified polymorphic DNA (RAPD) was examined as a potential tool to differentiate cryptic mosquito species. It proved to be a quick, effective means of finding genetic markers to separate two laboratory populations of morphologically indistinguishable African malaria vectors, Anopheles gambiae and An. arabiensis. In an initial screening of fifty-seven RAPD primers, 377 bands were produced, 295 of which differed between the two species. Based on criteria of interpretability, simplicity and reproducibility, thirteen primers were chosen for further screening using DNA from thirty individuals of each species. Seven primers produced diagnostic bands, five of which are described here. Some problematic characteristics of RAPD banding patterns are discussed and approaches to overcome these are suggested. PMID:8269099

  9. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate.

  10. Use of carbon-13 as a population marker for Anopheles arabiensis in a sterile insect technique (SIT) context

    OpenAIRE

    Knols Bart GJ; Mayr Leo; Hood-Nowotny Rebecca

    2006-01-01

    Abstract Background Monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the Sterile Insect Technique (SIT). Of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. Suitable ones include dye marking, genetic marking and chemical marking. Methods The feasibility of using the stable isotope of carbon, 13C, as a potential chemical marker for Anopheles arabien...

  11. Spatial repellency of transfluthrin-treated hessian strips against laboratory-reared Anopheles arabiensis mosquitoes in a semi-field tunnel cage

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    Ogoma Sheila B

    2012-03-01

    Full Text Available Abstract Background Vapour phase spatial repellents deter mosquitoes from attacking one or more humans in a protected space. Simulation models indicate that high coverage of spatial repellents can enhance the impact of long - lasting insecticide nets (LLINs and indoor residual spraying (IRS where mosquito vectors commonly bite humans outdoors. Here we report a preliminary evaluation of an effective, user-friendly prototype product for delivering spatial repellents to protect against malaria vector mosquitoes. Findings Protective efficacy of a 4.0 × 0.3 m strip of hessian sacking treated with 10 ml of transfluthrin was evaluated in a 60 m × 2 m ×2.5 m netting tunnel with malaria-free insectary-reared Anopheles arabiensis Patton mosquitoes. Personal protection, in terms of proportional reduction of exposure to bites, was measured by comparing human landing catches of volunteers with treated and untreated strips. A freshly treated hessian strip reduced mosquito attack rate on human volunteers by > 99% and consistently conferred > 90% protective efficacy for a period of 6 months. Over the entire study period, only 22 out of 1400 released mosquitoes bit volunteers using the treated sacking strip while 894 out of 1400 mosquitoes released into cages containing volunteers using an untreated strip fed upon them. Conclusion Locally available natural fibers may be promising absorbent substrates for delivering spatial repellents, such as transfluthrin, to protect against mosquitoes in tropical settings. However, these observations relate to a single prototype specimen of this particular device, therefore, much more detailed, well replicated studies are essential to establish long-term efficacy, effectiveness, practicability and affordability.

  12. Prolonged Colonisation, Irradiation, and Transportation do not Impede Mating Vigour and Competitiveness of Male Anopheles arabiensis Mosquitoes under Semifield Conditions in Northern Sudan

    International Nuclear Information System (INIS)

    Background. In Sudan, the Sterile Insect Technique (SIT) is being developed to suppress populations of Anopheles arabiensis. The present study was carried out to evaluate the impact of long-term colonisation, irradiation, and transportation on male vigour and mating competitiveness under controlled semi-field conditions. Materials and Methods. Male mosquitoes were irradiated in Khartoum as pupae and transported 400 km to the field site in Dongola. Wild males and females were collected as immature stages (larvae and pupae) from the field site and sexed immediately after adult emergence. Competition experiments were carried out to test the mating competitiveness and vigour of colonised males (non-irradiated or irradiated) against wild conspecifics in the semi-field system. Results. Mortality resulting from packaging and transportation from Khartoum to Dongola was low for adults (1.1% for irradiated and 1.3% for non-irradiated males). In contrast, all irradiated pupae died on their way to the field site. On average, 54.9% females were inseminated after one night. There were no differences between the number of females inseminated by colony males and those inseminated by wild males. Only a slightly significant difference between the numbers of females inseminated by irradiated males (14.0±1.7) or by wild males (19.7±1.7) was observed. However, the competitive index (CI) for irradiated and colony males when competed with wild males were 0.71 and 0.81 respectively. Conclusions. Packing and transportation methods for pupae need to be improved. Prolonged colonisation (68 generations), irradiation and transportation of adult males did not affect their ability to locate virgin females and compete against wild conspecifics. Irradiation, in contrast to many reports, only had a marginal effect on released males during the first night after their release. These findings support the feasibility of staging an SIT campaign against this malaria vector. (author)

  13. The complete mitochondrial genome of Anopheles minimus (Diptera: Culicidae) and the phylogenetics of known Anopheles mitogenomes.

    Science.gov (United States)

    Hua, Ya-Qiong; Ding, Yi-Ran; Yan, Zhen-Tian; Si, Feng-Ling; Luo, Qian-Chun; Chen, Bin

    2016-06-01

    Anopheles minimus is an important vector of human malaria in southern China and Southeast Asia. The phylogenetics of mosquitoes has not been well resolved, and the mitochondrial genome (mtgenome) has proven to be an important marker in the study of evolutionary biology. In this study, the complete mtgenome of An. minimus was sequenced for the first time. It is 15 395 bp long and encodes 37 genes, including 13 protein-coding genes (PCGs), 22 transfer RNAs (tRNAs), two ribosomal RNAs (rRNAs) and a non-coding region. The gene organization is consistent with those of known Anopheles mtgenomes. The mtgenome performs a clear bias in nucleotide composition with a positive AT-skew and a negative GC-skew. All 13 PCGs prefer to use the codon UUA (Leu), ATN as initiation codon but cytochrome-oxidase subunit 1 (COI) and ND5, with TCG and GTG, and TAA as termination codon, but COI, COII, COIII and ND4, all with the incomplete T. tRNAs have the typical clover-leaf structure, but tRNA(Ser(AGN)) is consistent with known Anopheles mtgenomes. The control region includes a conserved T-stretch and a (TA)n stretch, and has the highest A+T content at 93.1%. The phylogenetics of An. minimus with 18 other Anopheles species was constructed by maximum likelihood and Bayesian inference, based on concatenated PCG sequences. The subgenera, Cellia and Anopheles, and Nyssorhynchus and Kerteszia have mutually close relationships, respectively. The Punctulatus group and Leucosphyrus group of Neomyzomyia Series, and the Albitarsis group of Albitarsis Series were suggested to be monophyletic. The monophyletic status of the subgenera, Cellia, Anopheles, Nyssorhynchus and Kerteszia need to be further elucidated. PMID:26852698

  14. Resistance Mechanisms of Anopheles stephensi (Diptera: Culicidae) to Temephos

    OpenAIRE

    Aboozar Soltani; Hassan Vatandoost; MohammadAli Oshaghi; Naseh Maleki-Ravasan; AhmadAli Enayati; Fatemeh Asgarian

    2014-01-01

    Background: Anopheles stephensi is a sub-tropical species and has been considered as one of the most important vector of human malaria throughout the Middle East and South Asian region including the malarious areas of southern Iran. Current reports confirmed An. stephensi resistance to temephos in Oman and India. However, there is no comprehensive research on mechanisms of temephos resistance in An. stephensi in the literature. This study was designed in order to clarify the enzymatic and mol...

  15. The neotype of anopheles albitarsis (Diptera: culicidae O neótipo de Anopheles albitarsis (Diptera: Culicidae

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    Maria Goreti Rosa-Freitas

    1989-09-01

    Full Text Available Anopheles albitarsis neotype is described from specimens collected in Baradero, Argentina, in Shannon's trap, in horse and pig stables and on the progeny of engorded females. The description includes illustrations of adult female, male and female genitalias, scanning electron miscroscopy of the eggs and complete chaetotaxy of pupa and larva. The importance for electing a neotype is based on the realization that An. albitarsis is a complex of cryptic species. It is an attempt to provide typt-locality specimens with which other memebers of the group can be compared.O neótipo de Anopheles albitarsis é descrito a partir de espécimens coletados em armadilha tipo Shannon, em estábulos de cavalos e porcos e progênies de fêmeas ingurgitadas em Baradero, Argentina, localidade-tipo da espécie. A descrição inclui ilustrações da fêmea adulda, genitálias masculina e feminina, ovos em microscopia eletrônica de varredura e da quetotaxia completa das larvas de 4º estádio e pupas. A eleição de um neótipo para albitarsis baseia-se em dados recentes que apontam a espécie como um complexo de espécies crípticas, o que evidencia a importância de uma descrição detalhada de espécimens da localidade-tipo com o qual outros membros do grupo possam ser comparados.

  16. Resistance Mechanisms of Anopheles stephensi (Diptera: Culicidae to Temephos

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    Aboozar Soltani

    2015-10-01

    Full Text Available Background: Anopheles stephensi is a sub-tropical species and has been considered as one of the most important vector of human malaria throughout the Middle East and South Asian region including the malarious areas of southern Iran. Current reports confirmed An. stephensi resistance to temephos in Oman and India. However, there is no comprehensive research on mechanisms of temephos resistance in An. stephensi in the literature. This study was designed in order to clarify the enzymatic and molecular mechanisms of temephos resistance in this species.Methods: Profile activities of α- and ß-esterases, mixed function oxidase (MFO, glutathione-S-transferase (GST, insensitive acetylcholinesterase, and para-nitrophenyl acetate (PNPA-esterase enzymes were tested for An. stephensi strain with resistance ratio of 15.82 to temephos in comparison with susceptible strain.Results: Results showed that the mean activity of α-EST, GST and AChE enzymes were classified as altered indicating metabolic mechanisms have considerable role in resistance of An. stephensi to temephos. Molecular study using PCR-RFLP method to trace the G119S mutation in ACE-1 gene showed lack of the mutation responsible for organophosphate insecticide resistance in the temephos-selected strain of An. stephensi.Conclusion: This study showed that the altered enzymes but not targets site insensitivity of ACE-1 are responsible for temephos resistance in An. stephensi in south of Iran.

  17. Synthesis, Polymorphism, and Insecticidal Activity of Methyl 4-(4-chlorophenyl)-8-iodo-2-methyl-6-oxo-1,6-dihydro-4H-pyrimido[2,1-b]quinazoline-3-Carboxylate Against Anopheles arabiensis Mosquito.

    Science.gov (United States)

    Venugopala, Katharigatta N; Nayak, Susanta K; Gleiser, Raquel M; Sanchez-Borzone, Mariela E; Garcia, Daniel A; Odhav, Bharti

    2016-07-01

    Mosquitoes are the major vectors of pathogens and parasites including those causing malaria, the most deadly vector-borne disease. The negative environmental effects of most synthetic compounds combined with widespread development of insecticide resistance encourage an interest in finding and developing alternative products against mosquitoes. In this study, pyrimido[2,1-b]quinazoline derivative DHPM3 has been synthesized by three-step chemical reaction and screened for larvicide, adulticide, and repellent properties against Anopheles arabiensis, one of the dominant vectors of malaria in Africa. The title compound emerged as potential larvicide agent for further research and development, because it exerted 100% mortality, while adulticide activity was considered moderate. PMID:26841246

  18. Description of the egg of Anopheles (Anopheles intermedius (Peryassu, 1908 (Diptera: Culicidae by scanning electron microscopy

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1997-01-01

    Full Text Available The egg of Anopheles (Anopheles intermedius (Peryassu, 1908 is described and illustrated with scanning electron micrographs. Literature data on An. (Ano. maculipes (Theobald, 1903 is providedOs ovos de An. intermedius foram descritos e ilustrados por Costa Lima (1929. Este autor, baseando-se nos desenhos de Peryassu (1908 para An. maculipes, chamou atenção para o fato do ovo desta espécie ser semelhante ao de An. maculipes. Posteriormente, Causey e col. (1944, estudando os ovos de An. intermedius e An. maculipes ao estereomicroscópio, diferenciou-os por caracteres da franja. Em An. intermedius a franja é oblíqua ao eixo longitudinal do ovo, mas perpendicular em An. maculipes. Causey e col. (1944 ilustraram as variações morfológicas que encontraram na franja do ovo de An. intermedius. Os autores observaram que a franja apresentava-se descotínua em alguns espécimens de An. intermedius, tornando-se em pequenos círculos nessa região. Embora semelhante ao de An. maculipes, os ovos de An. intermedius podem ser facilmente reconhecidos por características da franja, flutuadores e tubérculos lobados, como pode ser observado na descrição. Contudo, será necessário estudar a morfologia dos ovos de outras espécies do subgênero para que se possa estabelecer as diferenças e fazer comparações precisas entre as espécies

  19. Anopheles darlingi and Anopheles marajoara (Diptera: Culicidae susceptibility to pyrethroids in an endemic area of the Brazilian Amazon

    Directory of Open Access Journals (Sweden)

    Allan Kardec Ribeiro Galardo

    2015-12-01

    Full Text Available Abstract: INTRODUCTION: This study aimed to evaluate the susceptibility of Anopheles darlingi Root (1926 and Anopheles marajoara Galvão & Damasceno (1942 to pyrethroids used by the National Malaria Control Program in Brazil. METHODS: Mosquitoes from Amapá, Brazilian Amazon, were assessed for resistance to cypermethrin, deltamethrin, and alpha-cypermethrin. Insecticide-impregnated bottles were used as suggested by the CDC/Atlanta. RESULTS: Diagnostic dose for Anopheles darlingi was 12.5µg/bottle during 30 min of exposure. Concentrations for Anopheles marajoara were 20µg/bottle of cypermethrin and deltamethrin and 12.5µg/bottle of alpha-cypermethrin. CONCLUSIONS : No resistance was recorded for Anopheles darlingi , but Anopheles marajoara requires attention.

  20. Efficacy of sunlight-activatable porphyrin formulates on larvae of Anopheles gambiae M and S molecular forms and An. arabiensis: a potential novel biolarvicide for integrated malaria vector control.

    Science.gov (United States)

    Fabris, Clara; Ouédraogo, Robert Kossivi; Coppellotti, Olimpia; Dabiré, Roch K; Diabaté, Abdoulaye; Di Martino, Piera; Guidolin, Laura; Jori, Giulio; Lucantoni, Leonardo; Lupidi, Giulio; Martena, Valentina; Sawadogo, Simon P; Soncin, Marina; Habluetzel, Annette

    2012-09-01

    Biolarvicides, such as microbial formulations based on Bacillus thuringiensis and B. sphaericus, have been found to be highly effective against mosquito larvae and are currently employed as eco-friendly alternatives to synthetic chemical insecticides for vector control. Recently, a porphyrin of natural origin has been suggested as a sunlight-activatable larvicide against the dengue vector Aedes aegypti. In order to validate the approach for the control of the malaria vector, we tested the photo-larvicidal activity of a novel porphyrin, namely meso-tri(N-methyl-pyridyl), mono(N-dodecyl-pyridyl)porphine, C12, associated with two specifically selected carriers, against Anopheles gambiae s.s. and An. arabiensis larvae, both laboratory reared and collected from malaria endemic sites in Burkina Faso. Both C12-porphyrin formulates, when administered to larvae at a 50μM porphyrin dose, were accumulated in the alimentary canal. Subsequent exposure of the porphyrin-loaded larvae to sunlight for short times (0.5-3h) led to a complete mortality. The high efficacy exhibited by a "foodstuff" porphyrin formulate also in the presence of typical larval food particles opens promising perspectives for the development of an effective photocidal larvicide.

  1. Shift in species composition in the Anopheles gambiae complex after implementation of long-lasting insecticidal nets in Dielmo, Senegal.

    Science.gov (United States)

    Sougoufara, S; Harry, M; Doucouré, S; Sembène, P M; Sokhna, C

    2016-09-01

    Long-lasting insecticidal nets (LLINs) and indoor residual spraying (IRS) are the cornerstones of malaria vector control. However, the effectiveness of these control tools depends on vector ecology and behaviour, which also largely determine the efficacy of certain Anopheles mosquitoes (Diptera: Culicidae) as vectors. Malaria vectors in sub-Saharan Africa are primarily species of the Anopheles gambiae complex, which present intraspecific differences in behaviour that affect how they respond to vector control tools. The focus of this study is the change in species composition in the An. gambiae complex after the implementation of LLINs in Dielmo, Senegal. The main findings referred to dramatic decreases in the proportions of Anopheles coluzzii and An. gambiae after the introduction of LLINs, and an increase in the proportion of Anopheles arabiensis. Two years after LLINs were first introduced, An. arabiensis remained the most prevalent species and An. gambiae had begun to rebound. This indicated a need to develop additional vector control tools that can target the full range of malaria vectors. PMID:27058993

  2. Bionomics of Anopheles spp. (Diptera: Culicidae) in a malaria endemic region of Sukabumi, West Java, Indonesia.

    Science.gov (United States)

    Stoops, Craig A; Rusmiarto, Saptoro; Susapto, Dwiko; Munif, Amurl; Andris, Heri; Barbara, Kathryn A; Sukowati, Supratman

    2009-12-01

    A 15-month bionomic study of Anopheles species was conducted in two ecologically distinct villages (coastal and upland) of Sukabumi District, West Java, Indonesia from June 2006 to September 2007. Mosquitoes were captured using human-landing collections at both sites. During the study, a total of 17,100 Anopheles mosquitoes comprising 13 Anopheles species were caught: 9,151 at the coastal site and 7,949 at the upland site. Anopheles barbirostris, Anopheles maculatus, and Anopheles vagus were the predominant species caught at the coastal site, and Anopheles aconitus, Anopheles barbirostris, and An. maculatus predominated in the upland site. Overall, species were exophagic at both sites, but there was variation between species. Anopheles aconitus was endophagic at the coastal site, exophagic at the upland site, collected most often in April 2007 and had a peak landing time between 22:00 and 23:00. Anopheles sundaicus was only collected at the coastal site, exophagic, collected most often in October 2006, and had a peak landing time between 19:00 and 20:00. Potential malaria vector species such An. aconitus, An. maculatus, and An. sundaicus were present throughout the year. None of the 7,770 Anopheles tested using CSP-ELISA were positive for malaria, although the risk for malaria outbreaks in Sukabumi district remains high.

  3. The Anopheles albitarsis complex with the recognition of Anopheles oryzalimnetes Wilkerson and Motoki, n. sp. and Anopheles janconnae Wilkerson and Sallum, n. sp. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Maysa Tiemi Motoki

    2009-09-01

    Full Text Available The Anopheles (Nyssorhynchus albitarsis complex includes six species: An. albitarsis, Anopheles oryzalimnetes Wilkerson and Motoki, n. sp., Anopheles marajoara, Anopheles deaneorum, Anopheles janconnae Wilkerson and Sallum, n. sp. and An. albitarsis F. Except for An. deaneorum, species of the complex are indistinguishable when only using morphology. The problematic distinction among species of the complex has made study of malaria transmission and ecology of An. albitarsis s.l. difficult. Consequently, involvement of species of the An. albitarsis complex in human Plasmodium transmission is not clear throughout its distribution range. With the aim of clarifying the taxonomy of the above species, with the exception of An. albitarsis F, we present comparative morphological and morphometric analyses, morphological redescriptions of three species and description of two new species using individuals from populations in Brazil, Paraguay, Argentina and Venezuela. The study included characters from adult females, males, fourth-instar larvae, pupae and male genitalia of An. albitarsis, An. marajoara, An. deaneorum and An. oryzalimnetes n. sp. For An. janconnae n. sp. only characters of the female, male and male genitalia were analyzed. Fourth-instar larvae, pupae and male genitalia characteristics of all five species are illustrated. Bionomics and distribution data are given based on published literature records.

  4. Distribution and frequency of kdr mutations within Anopheles gambiae s.l. populations and first report of the ace.1 G119S mutation in Anopheles arabiensis from Burkina Faso (West Africa.

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    Roch K Dabiré

    Full Text Available An entomological survey was carried out at 15 sites dispersed throughout the three eco-climatic regions of Burkina Faso (West Africa in order to assess the current distribution and frequency of mutations that confer resistance to insecticides in An. gambiae s.l. populations in the country. Both knockdown (kdr resistance mutation variants (L1014F and L1014S, that confer resistance to pyrethroid insecticides, were identified concomitant with the ace-1 G119S mutation confirming the presence of multiple resistance mechanisms in the An. gambiae complex in Burkina Faso. Compared to the last survey, the frequency of the L1014F kdr mutation appears to have remained largely stable and relatively high in all species. In contrast, the distribution and frequency of the L1014S mutation has increased significantly in An. gambiae s.l. across much of the country. Furthermore we report, for the first time, the identification of the ace.1 G119S mutation in An. arabiensis populations collected at 8 sites [corrected]. This mutation, which confers resistance to organophosphate and carbamate insecticides, has been reported previously only in the An. gambiae S and M molecular forms. This finding is significant as organophosphates and carbamates are used in indoor residual sprays (IRS to control malaria vectors as complementary strategies to the use of pyrethroid impregnated bednets. The occurrence of the three target-site resistance mutations in both An. gambiae molecular forms and now An. arabiensis has significant implications for the control of malaria vector populations in Burkina Faso and for resistance management strategies based on the rotation of insecticides with different modes of action.

  5. Mosquitoes of Anopheles hyrcanus (Diptera, Culicidae) Group: Species Diagnostic and Phylogenetic Relationships.

    Science.gov (United States)

    Khrabrova, Natalia V; Andreeva, Yulia V; Sibataev, Anuarbek K; Alekseeva, Svetlana S; Esenbekova, Perizat A

    2015-09-01

    Herein, we report the results of study of Anopheles species in Primorsk and Khabarovsk regions of Russia. Three species of the Anopheles hyrcanus group: An. kleini, An. pullus, and An. lesteri were identified by molecular taxonomic diagnostics for the first time in Russia. Surprisingly, An. sinensis, which earlier was considered the only species of Anopheles in Russian Far East, was not observed. We analyzed nucleotide variation in the 610-bp fragment of the 5' end of the cytochrome c oxidase subunit I (COI) region. All species possessed a distinctive set of COI sequences. A maximum likelihood phylogenetic tree was constructed for members of the hyrcanus group. The examined Anopheles hyrcanus group members could be divided into two major subgroups: subgroup 1 (An. hyrcanus and An. pullus) and subgroup 2 (An. sinensis, An. kleini, and An. lesteri), which were found to be monophyletic.

  6. Molecular comparison of topotypic specimens confirms Anopheles (Nyssorhynchus dunhami Causey (Diptera: Culicidae in the Colombian Amazon

    Directory of Open Access Journals (Sweden)

    Freddy Ruiz

    2010-11-01

    Full Text Available The presence of Anopheles (Nyssorhynchus dunhami Causey in Colombia (Department of Amazonas is confirmed for the first time through direct comparison of mtDNA cytochrome c oxidase I (COI barcodes and nuclear rDNA second internal transcribed spacer (ITS2 sequences with topotypic specimens of An. dunhami from Tefé, Brazil. An. dunhami was identified through retrospective correlation of DNA sequences following misidentification as Anopheles nuneztovari s.l. using available morphological keys for Colombian mosquitoes. That An. dunhami occurs in Colombia and also possibly throughout the Amazon Basin, is of importance to vector control programs, as this non-vector species is morphologically similar to known malaria vectors including An. nuneztovari, Anopheles oswaldoi and Anopheles trinkae. Species identification of An. dunhami and differentiation from these closely related species are highly robust using either DNA ITS2 sequences or COI DNA barcode. DNA methods are advocated for future differentiation of these often sympatric taxa in South America.

  7. Role of Anopheles (Kerteszia bellator as malaria vector in Southeastern Brazil (Diptera: Culicidae

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    Oswaldo Paulo Forattini

    1999-11-01

    Full Text Available New research concerning Anopheles bellator in the southeast of the State of São Paulo, Brazil, are reported. Adult females of this mosquito showed remarkable endophily and endophagy which was even greater than An. cruzii. The epidemiological role of this anopheline as a malaria vector is discussed.

  8. Mosquito repellent potential of Pithecellobium dulce leaf and seed against malaria vector Anopheles stephensi (Diptera: Culicidae)

    OpenAIRE

    Mohan Rajeswary; Marimuthu Govindarajan

    2016-01-01

    Objective: To determine the repellent properties of hexane, benzene, ethyl acetate, chloroform and methanol extract of Pithecellobium dulce (P. dulce) leaf and seed against Anopheles stephensi (An. stephensi). Methods: Repellent activity assay was carried out in a net cage (45 cm × 30 cm × 25 cm) containing 100 blood starved female mosquitoes of An. stephensi. This assay was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of P. ...

  9. Evaluation of leaf aqueous extract and synthesized silver nanoparticles using Nerium oleander against Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Roni, Mathath; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Hwang, Jiang-Shiou

    2013-03-01

    Green nanoparticle synthesis has been achieved using environmentally acceptable plant extract and ecofriendly reducing and capping agents. The present study was carried out to establish the larvicidal activity of synthesized silver nanoparticles (AgNPs) using leaf extract of Nerium oleander (Apocynaceae) against the first to fourth instar larvae and pupae of malaria vector, Anopheles stephensi (Diptera: Culicidae). Nanoparticles are being used in many commercial applications. It was found that aqueous silver ions can be reduced by the aqueous extract of the plant parts to generate extremely stable silver nanoparticles in water. The results were recorded from UV-Vis spectrum, Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy analysis. The production of the AgNPs synthesized using leaf extract of N. oleander was evaluated through a UV-Vis spectrophotometer in a wavelength range of 200 to 700 nm. This revealed a peak at 440 nm in N. oleander leaf extracts, indicating the production of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at 509.12 cm(-1) (C-H bend alkenes), 1,077.05 cm(-1) (C-O stretch alcohols), 1,600.63 cm(-1) (N-H bend amines), 2,736.49 and 2,479.04 cm(-1) (O-H stretch carboxylic acids), and 3,415.31 cm(-1) (N-H stretching due to amines group). An SEM micrograph showed 20-35-nm-size aggregates of spherical- and cubic-shaped nanoparticles. EDX showed the complete chemical composition of the synthesized nanoparticles of silver. Larvicidal activity of aqueous leaf extract of N. oleander and synthesized AgNPs was carried out against Anopheles stephensi, and the results showed that the highest larval mortality was found in the synthesized AgNPs against the first to fourth instar larvae and pupae of Anopheles stephensi with the following values: LC(50) of instar larvae 20.60, 24.90, 28.22, and 33.99 ppm; LC(90) of instar larvae 41.62, 50.33, 57.78, and 68.41

  10. Bioefficacy of Morinda tinctoria and Pongamia glabra plant extracts against the malaria vector Anopheles stephensi (Diptera: Culicidae

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    D. Amerasan

    2015-04-01

    Full Text Available Mosquito-borne diseases have an economic impact, including loss in commercial and labour outputs, particularly in countries with tropical and subtropical climates; however, no part of the world is free from vector-borne diseases. The aim of the present study was to investigate the larvicidal, adulticidal and ovicidal activity of dried leaf chloroform, ethyl acetate, acetone, aqueous, and methanol extracts of Morinda tinctoria and Pongamia glabra against larvae of Anopheles stephensi (Diptera: Culicidae. Larvae were exposed to varying concentrations of plant extracts for 24 h. All extracts showed moderate larvicidal effects after 24 h of exposure; however, the highest larval mortality was found with the leaf methanol extracts of M. tinctoria and P. glabra against the larvae of A. stephensi lethal concentration (LC50=136.24 and 141.05 ppm; LC90=342.67 and 368.89 ppm, respectively. The results of the adulticidal activity assays of chloroform, ethyl acetate, acetone, aqueous, and methanol extracts of M. tinctoria and P. glabra showed significant mortality against larvae of A. stephensi. The methanol extract showed maximum activity compared with the other extracts. The greatest effect on mean percentage hatch in the ovicidal assays was observed 48 h post-treatment. Percent hatch was inversely proportional to the concentration of extract, and directly proportional to the number of eggs. A mortality of 100% was observed with 100-400 ppm methanol extracts and 200-400 ppm aqueous extracts of M. tinctoria, and 200-400 ppm aqueous and methanol extracts of P. glabra. This study provides the first report of the larvicidal, adulticidal and ovicidal activities of M. tinctoria and P. glabra plant extracts against the malaria vector, A. stephensi, representing an ideal eco-friendly approach for its control.

  11. Unassisted isolated-pair mating of Anopheles gambiae (Diptera: Culicidae) mosquitoes.

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    Benedict, Mark Q; Rafferty, Cristina S

    2002-11-01

    Female Anopheles mosquitoes usually mate only once, but mating is seldom seen in small containers containing only one female and male. Therefore, matings are often performed among many adults in large cages or by forced copulation. Isolated-pair mating of Anopheles gambiae G3 strain-derived mosquitoes without forced copulation in small vials is described. We observed that the experimental variables eye color and male number were significant factors in the mating frequency. Females mated more frequently when three males were present over only one male. White-eyed females were more likely to be mated than wild-eyed females, but wild males mated more frequently than did white-eyed males. Experiments were also conducted to determine when mating was occurring by using wild-eye-color mosquitoes in isolated pairs. Almost no matings were observed before day 6 rather than the frequencies typically observed after 1-2 d in standard large-cage matings among large numbers of adults.

  12. Random amplified polymorphic DNA analysis of Anopheles nuneztovari (Diptera: Culicidae from Western and Northeastern Colombia

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    Carmen Elisa Posso

    2003-06-01

    Full Text Available Random amplified polymorphic DNA (RAPD markers were used to analyze 119 DNA samples of three Colombian Anopheles nuneztovari populations to study genetic variation and structure. Genetic diversity, estimated from heterozygosity, averaged 0.34. Genetic flow was greater between the two populations located in Western Colombia (F ST: 0.035; Nm: 6.8 but lower between these two and the northeastern population (F ST: 0.08; Nm: 2.8. According to molecular variance analysis, the genetic distance between populations was significant (phiST 0.1131, P < 0.001. The variation among individuals within populations (phiST 0.8869, P < 0.001was also significant, suggesting a greater degree of population subdivision, not considered in this study. Both the parameters evaluated and the genetic flow suggest that Colombian An. nuneztovari populations are co-specific.

  13. Cytogenetic evidence for a species complex within Anopheles pseudopunctipennis theobald (Diptera: Culicidae).

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    Coetzee, M; Estrada-Franco, J G; Wunderlich, C A; Hunt, R H

    1999-04-01

    Anopheles pseudopunctipennis was collected from Acapulco, Mexico and Sallee River, Grenada, West Indies and used in cross-mating experiments. Larvae from the cross, Mexico female X Grenada male, died in the third instar. However, adult progeny were obtained from the reciprocal cross Grenada female x Mexico male. These hybrid males had testes with apparently normal appearance but some without viable sperm. Polytene chromosomes obtained from hybrid females exhibited extensive asynapsis of the X chromosomes. Previously undescribed fixed inversion differences between the two populations were noted on the X chromosome. It is concluded that the two populations belong to different species. The Grenada population is designated An. pseudopunctipennis species C, since it is the third taxon recognized in this species complex.

  14. Systematic studies on Anopheles galvaoi Causey, Deane & Deane from the subgenus Nysssorhynchus blanchard (Diptera: Culicidae

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    Maria Anice Mureb Sallum

    2002-12-01

    Full Text Available Anopheles galvaoi, a member of the subgenus Nyssorhynchus, is redescribed based on morphological characters of the adults male and female, fourth-instar larva and pupa. Female, male genitalia, larval and pupal stages are illustrated. Data about medical importance, bionomics, and distribution are given based on literature records. Adult female of An. galvaoi can be easily misidentified as An. benarrochi Gabaldón and An. aquasalis Curry. A few characters are indicated for identifying female and immatures of An. galvaoi. Phylogenetic relationships among An. galvaoi and six other species of the Oswaldoi Subgroup are estimated using COII mtDNA and ITS2 rDNA gene sequences. Lectotype of An. galvaoi, an adult female from Rio Branco, State of Acre, is invalidated.

  15. [Historical review of the distribution of Anopheles (Nyssorhynchus) darlingi (Diptera: Culicidae) in the Peruvian Amazon].

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    Fernández, Roberto; Vera, Hubert; Calderón, Guillermo

    2014-04-01

    Anopheles (Nyssorhynchus) darlingi has been reported since 1931 in border areas of the department of Loreto, mainly along the borders with Brazil and Colombia. In 1994, during an outbreak of malaria, An. darlingi was found in neighboring towns to Iquitos. At present, its distribution has expanded considerably in Loreto. This paper reviews literature available for all possible information on the distribution of mosquitoes, particularly anopheline in the Amazon region of the country, with special emphasis on An darlingi. Entomological collections were also conducted in the departments of Madre de Dios and Ucayali in order to know and verify the distribution of An. darlingi. At present, the distribution of the species is confined to localities in southeastern Peru with Bolivia border towns, in a town near the Abujao River in the department of Ucayali, and widely in the northeastern region of the Amazon basin of Loreto in Peru. PMID:25123872

  16. Evaluating the potential of the sterile insect technique for malaria control: relative fitness and mating compatibility between laboratory colonized and a wild population of Anopheles arabiensis from the Kruger National Park, South Africa

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    Hunt Richard H

    2011-10-01

    Full Text Available Abstract Background The successful suppression of a target insect population using the sterile insect technique (SIT partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them from successfully competing for mates in the wild. This study investigated the fitness and sexual cross-compatibility between samples of field collected and laboratory reared An. arabiensis under laboratory conditions. Results The physiological and reproductive fitness of the MALPAN laboratory strain is not substantially modified with respect to the field population at Malahlapanga. Further, a high degree of mating compatibility between MALPAN and the Malahlapanga population was established based on cross-mating experiments. Lastly, the morphological characteristics of hybrid ovarian polytene chromosomes further support the contention that the MALPAN laboratory colony and the An. arabiensis population at Malahlapanga are genetically homogenous and therefore compatible. Conclusions It is concluded that the presence of a perennial and isolated population of An. arabiensis at Malahlapanga presents a unique opportunity for assessing the feasibility of SIT as a malaria vector control option. The MALPAN laboratory colony has retained sufficient enough measures of reproductive and physiological fitness to present as a suitable candidate for male sterilization, mass rearing and subsequent mass release of sterile males at Malahlapanga in order to further assess the feasibility of SIT in a field setting.

  17. Molecular taxonomy of Anopheles (Nyssorhynchus) benarrochi (Diptera: Culicidae) and malaria epidemiology in southern Amazonian Peru.

    Science.gov (United States)

    Conn, Jan E; Moreno, Marta; Saavedra, Marlon; Bickersmith, Sara A; Knoll, Elisabeth; Fernandez, Roberto; Vera, Hubert; Burrus, Roxanne G; Lescano, Andres G; Sanchez, Juan Francisco; Rivera, Esteban; Vinetz, Joseph M

    2013-02-01

    Anopheline specimens were collected in 2011 by human landing catch, Shannon and CDC traps from the malaria endemic localities of Santa Rosa and San Pedro in Madre de Dios Department, Peru. Most specimens were either Anopheles (Nyssorhynchus) benarrochi B or An. (Nys.) rangeli, confirmed by polymerase chain reaction-restriction fragment length polymorphism-internal transcribed spacer 2 (PCR-RFLP-ITS2) and, for selected individuals, ITS2 sequences. A few specimens from Lupuna, Loreto Department, northern Amazonian Peru, were also identified as An. benarrochi B. A statistical parsimony network using ITS2 sequences confirmed that all Peruvian An. benarrochi B analyzed were identical to those in GenBank from Putumayo, southern Colombia. Sequences of the mtDNA COI BOLD region of specimens from all three Peruvian localities were connected using a statistical parsimony network, although there were multiple mutation steps between northern and southern Peruvian sequences. A Bayesian inference of concatenated Peruvian sequences of ITS2 + COI detected a single clade with very high support for all An. benarrochi B except one individual from Lupuna that was excluded. No samples were positive for Plasmodium by CytB-PCR.

  18. Mosquito repellent potential of Pithecellobium dulce leaf and seed against malaria vector Anopheles stephensi (Diptera: Culicidae

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    Mohan Rajeswary

    2016-03-01

    Full Text Available Objective: To determine the repellent properties of hexane, benzene, ethyl acetate, chloroform and methanol extract of Pithecellobium dulce (P. dulce leaf and seed against Anopheles stephensi (An. stephensi. Methods: Repellent activity assay was carried out in a net cage (45 cm × 30 cm × 25 cm containing 100 blood starved female mosquitoes of An. stephensi. This assay was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of P. dulce were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the concentration of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 leaf and seed methanol extract of P. dulce provided over 180 min and 150 min protection, respectively. Conclusions: Crude extracts of P. dulce exhibit the potential for controlling malaria vector mosquito An. stephensi.

  19. Isoenzymatic analysis of four Anopheles (Kerteszia) bellator Dyar & Knab (Diptera: Culicidae) populations.

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    de Carvalho-Pinto, Carlos José; Lourenço-de-Oliveira, Ricardo

    2003-12-01

    Anopheles bellator is a small silvatic bromelia-breeding mosquito and is a primary human malaria vector species in Southern Brazil. The bromelia-breeding habitat of the species should accompany the Atlantic forest coastal distribution, where bromeliads are abundant. Nonetheless, records on An. bellator collections show a gap in the species geographical distribution. An. bellator has been recorded in Southern Brazil and in the Brazilian states of Bahia and Paraíba. It appears again in the island of Trinidad, in Trinidad and Tobago. The aim of this work was to measure gene flow between different populations of An. bellator collected in the northern and southern extremes of the geographic distribution of this species. Mosquitoes were captured in forest borders in Santa Catarina, São Paulo, and Bahia states in Brazil and in the island of Trinidad in Republic of Trinidad and Tobago. Genetic distances varied between 0.076 and 0.680, based on enzymatic profiles from 11 distinct isoenzymes. Results indicate the existence of low-level gene flow between Brazilian populations of An. bellator, and a gene flow was even lower between the Brazilian and the Trinidad populations. This finding lead us to hypothesize that An. bellator did not spread along the coast, but reached northeastern areas through inland routes.

  20. Isoenzymatic analysis of four Anopheles (Kerteszia bellator Dyar & Knab (Diptera: Culicidae populations

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    Carvalho-Pinto Carlos José de

    2003-01-01

    Full Text Available Anopheles bellator is a small silvatic bromelia-breeding mosquito and is a primary human malaria vector species in Southern Brazil. The bromelia-breeding habitat of the species should accompany the Atlantic forest coastal distribution, where bromeliads are abundant. Nonetheless, records on An. bellator collections show a gap in the species geographical distribution. An. bellator has been recorded in Southern Brazil and in the Brazilian states of Bahia and Paraíba. It appers again in the island of Trinidad, in Trinidad and Tobago. The aim of this work was to measure gene flow between different populations of An. bellator collected in the northern and southern extremes of the geographic distribution of this species. Mosquitoes were captured in forest borders in Santa Catarina, São Paulo, and Bahia states in Brazil and in the island of Trinidad in Republic of Trinidad and Tobago. Genetic distances varied between 0.076 and 0.680, based on enzymatic profiles from 11 distinct isoenzymes. Results indicate the existence of low-level gene flow between Brazilian populations of An. bellator, and a gene flow was even lower between the Brazilian and the Trinidad populations. This finding lead us to hypothesize that An. bellator did not spread along the coast, but reached northeastern areas through inland routes.

  1. Larvicidal effects of endophytic and basidiomycete fungus extracts on Aedes and Anopheles larvae (Diptera, Culicidae

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    Augusto Bucker

    2013-08-01

    Full Text Available Introduction In vitro bioassays were performed to access the larvicidal activity of crude extracts from the endophytic fungus Pestalotiopsis virgulata (Melanconiales, Amphisphaeriaceae and the saprophytic fungus Pycnoporus sanguineus (Basidiomycetes, Polyporaceae against the mosquitoes Aedes aegypti and Anopheles nuneztovari. Methods The extracts were tested at concentrations of 100, 200, 300, 400 and 500ppm. Ethyl acetate mycelia (EAM extracts and liquid culture media (LCM from Pe. virgulata and Py. sanguineus were tested against third instar larvae of Ae. aegypti and An. nuneztovari. Results The larvicidal activity of the EAM extracts from Pe. virgulata against Ae. aegypti had an LC50=101.8ppm, and the extract from the basidiomycete fungus Py. sanguineus had an LC50=156.8ppm against the Ae. aegypti larvae. The Pe. virgulata extract had an LC50=16.3ppm against the An. nuneztovari larvae, and the Py. sanguineus extract had an LC50=87.2ppm against these larvae. Conclusions These results highlight the larvicidal effect of EAM extracts from the endophyte Pe. virgulata against the two larval mosquitoes tested. Thus, Pe. virgulata and Py. sanguineus have the potential for the production of bioactive substances against larvae of these two tropical disease vectors, with An. nuneztovari being more susceptible to these extracts.

  2. Sequencing and analysis of the complete mitochondrial genome in Anopheles culicifacies species B (Diptera: Culicidae).

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    Hua, Ya-Qiong; Yan, Zhen-Tian; Fu, Wen-Bo; He, Qi-Yi; Zhou, Yong; Chen, Bin

    2016-07-01

    The complete mitochondrial genome sequence of Anopheles culicifacial species B was sequenced in this study. The length of the mitochondrial genome is 15 330 bp, which contains 13 protein-coding genes (PCGs), 22 tRNA genes, two rRNA genes, and a non-coding control region. The gene order and the gene composition are consistent with those previously reported for other mosquito species. The initiation codon of the PCGs complies with the ATN rule except for COI using TCG and ND5 using GTG as a start codon, and the termination codon is TAA or imcomplete, an only T. The total base composition is 40.4% A, 38.1% T, 12.4% C, and 9.1% G. The phylogenetic tree based on the sequences of 13 protein-coding genes showed that these species were classified into two clades, corresponding to the subgenus Cellia and subgenus Nyssorhynchus. An. culicifacies species B of Myzomyia Series was clustered with An. gambiae of Pyretophorus Series with a high bootstrap value of 100%. The complete mitogenome data can provide a basis for molecular identification and phylogenetic studies of mosquito species. PMID:26114319

  3. Variability and genetic differentiation among Anopheles (Ano. intermedius Chagas, 1908 and Anopheles (Ano. mattogrossensis Lutz & Neiva, 1911 (Diptera: Culicidae from the Brazilian Amazon

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    Joselita Maria Mendes dos Santos

    2005-10-01

    Full Text Available Anopheles (Anopheles intermedius and Anopheles (Ano. mattogrossensis are Brazilian anopheline species belonging to the scarcely studied Anopheles subgenus. Few studies have been done on the genetic differentiation of these species. Both species have been found infected by Plasmodium and are sympatric with other anopheline species from the Nyssorhynchus subgenus. Eighteen enzymatic loci were analyzed in larval specimens of An. intermedius and An. mattogrossensis aiming to estimate the variability and genetic differentiation between these species. An. mattogrossensis population showed higher genetic variability (P = 44.4 and Ho = 0.081 ± 0.031 than that of An. intermedius (P = 33.3 and Ho = 0.048 ± 0.021. Most analyzed loci showed genotypic frequencies according to Hardy-Weinberg equilibrium, except for LAP1 and LAP2 in An. intermedius, and EST1 and PGM loci in An. mattogrossensis. The genetic distance between these species (D = 0.683 was consistent with the inter-specific values reported for Anopheles subgenus. We verified that the polymorphism and heterozygosity percentile values found in both species and compared to those in the literature, showed no relation between the level of isozyme variability and geographical distribution. The low variability found in these two species is probably more related to the niche they occupy than to their geographic distribution.

  4. Chemical Constituents and Combined Larvicidal Effects of Selected Essential Oils against Anopheles cracens (Diptera: Culicidae

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    Jitrawadee Intirach

    2012-01-01

    Full Text Available A preliminary study on larvicidal activity against laboratory-colonized Anopheles cracens mosquitos revealed that five of ten plant oils at concentration of 100 ppm showed 95–100% larval mortality. The essential oils of five plants, including Piper sarmentosum, Foeniculum vulgare, Curcuma longa, Myristica fragrans, and Zanthoxylum piperitum, were then selected for chemical analysis, dose-response larvicidal experiments, and combination-based bioassays. Chemical compositions analyzed by gas chromatography coupled to mass spectrometry demonstrated that the main component in the oil derived from P. sarmentosum, F. vulgare, C. longa, M. fragrans, and Z. piperitum was croweacin (71.01%, anethole (63.00%, ar-turmerone (30.19%, safrole (46.60%, and 1,8-cineole (21.27%, respectively. For larvicidal bioassay, all five essential oils exerted promising efficacy in a dose-dependent manner and different performances on A. cracens after 24 hours of exposure. The strongest larvicidal potential was established from P. sarmentosum, followed by F. vulgare, C. longa, M. fragrans, and Z. piperitum, with LC50 values of 16.03, 32.77, 33.61, 40.00, and 63.17 ppm, respectively. Binary mixtures between P. sarmentosum, the most effective oil, and the others at the highest ratio were proved to be highly efficacious with a cotoxicity coefficient value greater than 100, indicating synergistic activity. Results of mixed formulations of different essential oils generating synergistic effects may prove helpful in developing effective, economical, and ecofriendly larvicides, as favorable alternatives for mosquito management.

  5. Larvicidal activity of indigenous plant extracts on the rural malarial vector, Anopheles culicifacies Giles. (Diptera: Culicidae

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    K. Kovendan

    2014-12-01

    Full Text Available Vector control is one of the most important components in combating vector-borne diseases throughout the world. Application of insecticides is a widely known and popular vector control strategy. The objective of the present study was to evaluate the larvicidal activity of the hexane, diethyl ether, ethyl acetate and acetone extracts of Abutilon indicum, Hyptis suaveolens and Leucas aspera against third-stage larvae of Anopheles culicifiacies. The results clearly suggest that all three selected plant extracts exhibited moderate larvicidal activity after 24, 48 and 72 h at 250, 500, 750 and 1000 ppm; the lethal concentrations (LC at 50% and 90% of A. indicum, H. suaveolens against third instar larvae at 24, 48 and 72 h (hexane, diethyl ether, ethyl acetate and acetone were as follows: A. indicum, LC50=1031.65, 949.18, 833.58 and 673.68 ppm; LC90=2215.87, 2234.39, 2152.97 and 2455.10 ppm; H. suaveolens, LC50=423.00, 347.50, 236.58 and 217.24 ppm; LC90=1431.91, 1292.15, 1138.49 and 1049.27 ppm and L. aspera, LC50=559.77, 401.56, 299.71 and 263.01 ppm; LC90=1400.80, 1549.31, 1157.96 and 1108.72 ppm at 24 h, respectively. Overall, the highest larvicidal activity was observed with H. suaveolens extract followed by L. aspera and A. indicum at various concentrations at 48 and 72 h, respectively. The objective of this investigation was an attempt to search for a user- and eco-friendly vector control agent. The study proved that the selected plant leaf extracts could serve as potent larvicidal agents against A. culicifacies in vector control programs.

  6. Antimalarial efficacy of dynamic compound of plumbagin chemical constituent from Plumbago zeylanica Linn (Plumbaginaceae) against the malarial vector Anopheles stephensi Liston (Diptera: Culicidae).

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    Pradeepa, Venkatraman; Sathish-Narayanan, Subbiah; Kirubakaran, Suyambulingam Arunachalam; Senthil-Nathan, Sengottayan

    2014-08-01

    In the present investigation, the effective root compound of plumbagin of Plumbago zeylanica (Plumbaginaceae) was evaluated for chemical constituent and antimalarial effect against the fourth instar larvae of Anopheles stephensi Liston (Diptera). In the chromatographic analyses of root compound with Rf value of 0.788 and NMR analyses also revealed that the effective compound contain naphthoquinone plumbagin were identified as the major chemical constituent. Larval mortality was observed after 3 h of exposure period. The plumbagin compound showed remarkable larvicidal activity against A. stephensi (LC50 32.65 and LC9072.27 ppm). Histopathological effects of compound was observed in the treated larvae. Based on the results, the plumbagin compound of P. zeylanica can be considered as a new source of natural larvicide for the control of malarial vector.

  7. Lineage divergence detected in the malaria vector Anopheles marajoara (Diptera: Culicidae in Amazonian Brazil

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    Povoa Marinete M

    2010-10-01

    Full Text Available Abstract Background Cryptic species complexes are common among anophelines. Previous phylogenetic analysis based on the complete mtDNA COI gene sequences detected paraphyly in the Neotropical malaria vector Anopheles marajoara. The "Folmer region" detects a single taxon using a 3% divergence threshold. Methods To test the paraphyletic hypothesis and examine the utility of the Folmer region, genealogical trees based on a concatenated (white + 3' COI sequences dataset and pairwise differentiation of COI fragments were examined. The population structure and demographic history were based on partial COI sequences for 294 individuals from 14 localities in Amazonian Brazil. 109 individuals from 12 localities were sequenced for the nDNA white gene, and 57 individuals from 11 localities were sequenced for the ribosomal DNA (rDNA internal transcribed spacer 2 (ITS2. Results Distinct A. marajoara lineages were detected by combined genealogical analysis and were also supported among COI haplotypes using a median joining network and AMOVA, with time since divergence during the Pleistocene (COI sequences at the 3' end were more variable, demonstrating significant pairwise differentiation (3.82% compared to the more moderate 2.92% detected by the Folmer region. Lineage 1 was present in all localities, whereas lineage 2 was restricted mainly to the west. Mismatch distributions for both lineages were bimodal, likely due to multiple colonization events and spatial expansion (~798 - 81,045 ya. There appears to be gene flow within, not between lineages, and a partial barrier was detected near Rio Jari in Amapá state, separating western and eastern populations. In contrast, both nDNA data sets (white gene sequences with or without the retention of the 4th intron, and ITS2 sequences and length detected a single A. marajoara lineage. Conclusions Strong support for combined data with significant differentiation detected in the COI and absent in the nDNA suggest that

  8. Confirmation of Anopheles (Anopheles calderoni Wilkerson, 1991 (Diptera: Culicidae in Colombia and Ecuador through molecular and morphological correlation with topotypic material

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    Ranulfo González

    2010-12-01

    Full Text Available The morphologically similar taxa Anopheles calderoni, Anopheles punctimacula, Anopheles malefactor and Anopheles guarao are commonly misidentified. Isofamilies collected in Valle de Cauca, Colombia, showed morphological characters most similar to An. calderoni, a species which has never previously been reported in Colombia. Although discontinuity of the postsubcostal pale spots on the costa (C and first radial (R1 wing veins is purportedly diagnostic for An. calderoni, the degree of overlap of the distal postsubcostal spot on C and R1 were variable in Colombian specimens (0.003-0.024. In addition, in 98.2% of larvae, seta 1-X was located off the saddle and seta 3-C had 4-7 branches in 86.7% of specimens examined. Correlation of DNA sequences of the second internal transcribed spacer and mtDNA cytochrome c oxidase subunit I gene (COI barcodes (658 bp of the COI gene generated from Colombian progeny material and wild-caught mosquitoes from Ecuador with those from the Peruvian type series of An. calderoni confirmed new country records. DNA barcodes generated for the closely related taxa, An. malefactor and An. punctimacula are also presented for the first time. Examination of museum specimens at the University of the Valle, Colombia, revealed the presence of An. calderoni in inland localities across Colombia and at elevations up to 1113 m.

  9. Fauna and some biological characteristics of Anopheles mosquitoes (Diptera:Culicidae) in Kalaleh County, Golestan Province, northeast of lran

    Institute of Scientific and Technical Information of China (English)

    Aioub Sofizadeh; Hamideh Edalat; Mohammad Reza Abai; Ahmad Ali Hanafi-Bojd

    2016-01-01

    Objective: To determine fauna and some ecological aspects of Anopheles mosquitoes in northeast of Iran. Methods: In this descriptive study, 3 villages in Kalaleh County were selected in different geographical zones. Anopheles mosquitoes were collected biweekly from May to October using standard dipping method for larvae, and hand catch, total catch, artificial pit shelter as well as night-biting collections on human and animal baits for adults. Results: Totally 399 larvae and 2 602 adults of Anopheles mosquitoes were collected and identified as 2 species: Anopheles superpictus s.l. (An. superpictus s.l.) and Anopheles maculipennis s.l. The dominant species was An. superpictus s.l. (92.1%). Activity of these mosquitoes found to be started from middle of May and extended till September with two peaks of activity in July and August. Conclusions: An. superpictus s.l. as one of the main malaria vectors in Iran as well as some other parts of the world is the dominant species in the study area. This species has high potential for transmission and possibility of establishing a transmission cycle with low abundance. Other species, Anopheles maculipennis s.l. also has introduced as a malaria vector in northern parts of Iran. As this Anopheles is a complex species, genetic studies are recommended to determine the members of this complex in the study area.

  10. Ovicidal, larvicidal and adulticidal properties of Asparagus racemosus (Willd.) (Family: Asparagaceae) root extracts against filariasis (Culex quinquefasciatus), dengue (Aedes aegypti) and malaria (Anopheles stephensi) vector mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2014-04-01

    Several diseases are associated to the mosquito-human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. The present investigation was undertaken to study the ovicidal, larvicidal and adulticidal activities of crude hexane, ethyl acetate, benzene, chloroform and methanol extracts of root of Asparagus racemosus were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi (Diptera: Culicidae). The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. The methanol extract of Asparagus racemosus against Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi exerted 100% mortality (zero hatchability) at 375, 300 and 225 ppm, respectively. Control eggs showed 99-100% hatchability. The larval mortality was observed after 24 h of exposure. All extracts showed moderate larvicidal effects; however, the highest larval mortality was found in methanol extract of root of Asparagus racemosus against the larvae of Culex quinquefasciatus, Aedes aegypti and Anopheles stephensi with the LC50 and LC90 values were 115.13, 97.71 and 90.97 ppm and 210.96, 179.92, and 168.82 ppm, respectively. The adult mortality was observed after 24 h recovery period. The plant crude extracts showed dose-dependent mortality. At higher concentrations, the adult showed restless movement for some times with abnormal wagging and then died. Among the extracts tested, the highest adulticidal activity was observed in

  11. Electrophysiological responses of gustatory receptor neurons on the labella of the common malaria mosquito Anopheles quadrimaculatus Say (Diptera: Culicidae)

    Science.gov (United States)

    We recorded electrical responses from sensory cells associated with gustatory sensilla on the labella of female Anopheles quadrimaculatus to salt, sucrose, quinine (a feeding deterrent) and the insect repellent, N,N-diethyl-3-methylbenzamide (DEET). A salt-sensitive cell responded to increasing con...

  12. Effect of Bacillus sphaericus Neide on Anopheles (Diptera: Culicidae and associated insect fauna in fish ponds in the Amazon

    Directory of Open Access Journals (Sweden)

    Francisco Augusto da Silva Ferreira

    2015-09-01

    Full Text Available ABSTRACTWe analyzed the effects of Bacillus sphaericus on Anopheles larvae and on the associated insect fauna in fish farming ponds. Five breeding sites in the peri-urban area of the city of Manaus, AM, Brazil, were studied. Seven samples were collected from each breeding site and B. sphaericus was applied and reapplied after 15 days. The samples were made at 24 h before application, 24 h post-application and 5 and 15 days post-application. We determined abundance, larval reduction and larval density for Anopheles, and abundance, richness, Shannon diversity index and classified according to the functional trophic groups for associated insect fauna. A total of 904 Anopheles larvae were collected and distributed into five species. Density data and larval reduction demonstrated the rapid effect of the biolarvicide 24 h after application. A total of 4874 associated aquatic insects belonging to six orders and 23 families were collected. Regression analysis of diversity and richness indicated that the application of the biolarvicide had no influence on these indices and thus no effect on the associated insect fauna for a period of 30 days. B. sphaericus was found to be highly effective against the larvae of Anopheles, eliminating the larvae in the first days after application, with no effect on the associated insect fauna present in the fish ponds analyzed.

  13. Extent of digestion affects the success of amplifying human DNA from blood meals of Anopheles gambiae (Diptera: Culicidae)

    NARCIS (Netherlands)

    Mukabana, W.R.; Takken, W.; Seda, P.; Killeen, G.F.; Hawley, W.A.; Knols, B.G.J.

    2002-01-01

    The success of distinguishing blood meal sources of Anopheles gambiae Giles through deoxyribonucleic acid (DNA) profiling was investigated by polymerase chain reaction (PCR) amplification at the TC-11 and VWA human short tandem repeats (STR) loci. Blood meal size and locus had no significant effect

  14. Man-biting activity of Anopheles (Nyssorhynchus albimanus and An. (Kerteszia neivai (Diptera: Culicidae in the Pacific Lowlands of Colombia

    Directory of Open Access Journals (Sweden)

    Yezid Solarte

    1996-04-01

    Full Text Available The daily man-biting activity of Anopheles (Nyssorhynchus albimanus and An. (Kerteszia neivai was determined in four ecologically distinct settlements of the Naya River, Department of Valle, Colombia. Differences were found among the settlements with respect to the mosquito species present, intradomiciliary and extradomiciliary biting activity and population densities.

  15. Mosquitocidal activity of Polygala arvensis Willd against Aedes aegypti (Linn., Anopheles stephensi (Liston. and Culex quinquefasciatus (Say. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    M. Deepa

    2014-12-01

    Full Text Available To determine the larvicidal, ovicidal and repellent activities of benzene and methanol extract of Polygala arvensis against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus Twenty five 3rd instar larvae of selected mosquitoes species were exposed to various concentrations (60-300 ppm and were assayed in the laboratory by using the protocol of WHO 2005; the 24 h LC50 values of the P. Arvensis leaf extract was determined following Probit analysis. The ovicidal activity was determined against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus exposed to variousconcentrations were tested under laboratory conditions and the hatch rates were assessed 120hrs post treatment. The repellent efficacy was determined against selected mosquitoes at three concentrations viz., 1.0, 2.0 and 3.0 mg/cm2 under the laboratory conditions. The LC50 and LC90 values of benzene and methanol extract of P. arvensis against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus larvae in 24 h were 75.32, 88.26, 82.46, 58.21, 46.37, 42.68 and 260.48, 275.26, 251.39, 208.45, 189.82 and 130.44 ppm, respectively. It has been noticed that the higher concentrations of P. arvensis extractspossesses strong ovicidal activity at 200 ppm concentration against Ae. aegypti, An. stephensi and C. quinquefasciatus, no egg hatchability was recorded. In the same way, methanol extracts showed maximum ovicidal activity followed by benzene extract against selected vector mosquitoes. In repellent activity, among two extracts tested P. arvensis methanol extract had strong repellent action against selected mosquitoes as it provided 100% protection against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus for 280min. From the results it can be concluded the P. arvensis extract was an excellent potential for controlling Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes.

  16. Toxicity of pirimiphos methyl (Actellic 25EC) on Anopheles gambiae s.s., Culex quinquefasciatus (Diptera: Culicidae), and potential biocontrol agent, Poecilia reticulata (Pisces: Poeciliidae).

    Science.gov (United States)

    Anogwih, Joy A

    2014-08-01

    The toxicity of an emulsifiable formulation of pirimiphos methyl (Actellic 25EC) on Anopheles gambiae s.s. Giles, Culex quinquefasciatus Say (Diptera: Culicidae), and predator fish Poecilia reticulata Peters (Pisces: Poeciliidae) was investigated. Acute toxicity tests were carried out to determine the effect of the larvicide on mosquito larvae and fish species. To investigate the nontarget effects on P. reticulata, fish of similar size (3.5 +/- 0.2 cm) were randomly selected and exposed for 28 d, under static renewal bioassay, to sublethal concentrations of the larvicide capable of killing 30 and 70% of Cx. quinquefasciatus. The 24 h LC50 value of pirimiphos methyl on the test organisms ranged between 20.44 and 697.30 microg liter(-1). The ultrastructural changes observed in the intestinal cells of P. reticulata were characterized by degenerating cell membranes with gradual loss of gray area in pycnotic nucleus at lower concentration. Marked damage was found at higher concentration including distinct loss of gray areas in cytosol, absence of cristae, numerous ruptures, and several dead cells. Pirimiphos methyl was toxic to a predatory fish species, and for its relevance in vector control and crop protection, warrants cumulative assessment to establish its comprehensive ecological risk, and the dosage required for field larviciding.

  17. Mosquito larvicidal and ovicidal properties of Pemphis acidula Frost. (Lythraceae) against Culex tritaeniorhynchus Giles and Anopheles subpictus Grassi (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    K. Samidurai

    2012-01-01

    Objective: This study was undertaken to assess the larvicidal and ovicidal potential of the crude methanol, benzene and acetone solvent extracts from the medicinal plant Pemphis acidula (Pe. acidula) against the medically important mosquito vectors, Culex tritaeniorhynchus (Cx. tritaeniorhynchus) and Anopheles subpictus (An. subpictus) were exposed to various concentrations and (Diptera: Culicidae). Methods: Twenty five late third instar of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO 2005. The larval mortality was observed 24 h of treatment. Hundred eggs of Cx. tritaeniorhynchus and An. subpictus were exposed to various concentrations and were assayed in the laboratory by using the protocol of Su and Mulla 1998. The ovicidal activity was observed 48 h of treatment. Results: The LC50 and LC90 values being 10.81and 20.64 and 22.10 and 43.71 ppm and hundred percent of egg mortality was observed at 350 and 400 ppm methanol extract of Pe. acidula against Cx. tritaeniorhynchus and An. subpictus, respectively. Conclusion: These results suggest that the leaf extracts have the potential to be used as an ideal ecofriendly approach for the control of mosquitoes.

  18. Morphological Analysis of Anopheles vagus Donitz, 1902 (Diptera : Culicidae in fresh water and brackish water habitats = Variasi Morfologi Anopheles vagus Donitz, 1902 (Diptera : Culicidae dari Habitat Air Tawar dan Air Payau

    Directory of Open Access Journals (Sweden)

    Siti Alfiah

    2014-10-01

    Full Text Available ENGLISHAbstractAnopheles subpictus had habitat variation and showed genetic difference. So, the variation of habitat of An. vagus may support the hypothesa that An. vagus had genetic and morphology variation, same as An. subpictus.The aimed of this research was analyze morphology and chaetotaxy difference between An. vagus in fresh water and brackish water. The subject of the study was An. vagus collected from Kesongo Village, Tuntang Subdistrict, Semarang (fresh water and Jatimalang Village, Purwodadi Subdistrict, Purworejo (brackish water. Anopheles vagus were collected and individually reared. One sample in every batch was used to make larvae skin, pupae skin and adult specimen of An. vagus. The result showed that there were intra and inter population variation between An. vagus in fresh water and brackish water. The variations were on the size and number of hair branches and filaments. The conclution of this research were the morphology and chaetotaxy of female An. vagus in fresh water and brackish water showed no different. Intra and interpopulation An. vagus in fresh water and brackish water were caused by the difference of geography location (allopatric speciation.INDONESIANVariasi habitat terjadi pada An. subpictus, variasi habitat yang berbeda menunjukkan variasi genetik yang berbeda. Oleh karena itu variasi habitat An. vagus diduga akan bepengaruh terhadap variasi genetik dan morfologi. Tujuan penelitian adalah menganalisis perbedaan morfologi dan kaetotaksi Anopheles vagus habitat air tawar dan air payau. Subyek penelitian adalah An. vagus habitat air tawar di Desa Kesongo, Kecamatan Tuntang, Kabupaten Semarang dan An. vagus habitat air payau di Desa Jatimalang, Kecamatan Purwodadi, Kabupaten Purworejo. Anopheles vagus yang diperoleh, di rearing secara individual. Tiap indukan diambil satu sampel keturunannya dan dibuat preparat skin larva, skin pupa dan nyamuk dewasa betina. Hasil menunjukkan bahwa Anopheles vagus betina habitat air

  19. Larvicidal and repellent properties of Adansonia digitata against medically important human malarial vector mosquito Anopheles stephensi (Diptera: Culicidae)

    OpenAIRE

    K. Krishnappa , K. Elumalai , S. Dhanasekaran & J. Gokulakrishnan

    2012-01-01

    Background & objectives: Development of plant-based alternative compounds for mosquito control has gainedimportance now-a-days, in view of increasing resistance in mosquito vectors to existing insecticides. The larvicidaland repellent activities of benzene, chloroform, hexane and methanol leaf extracts of Indian medicinal plant,Adansonia digitata were investigated against malarial vector, Anopheles stephensi.Methods: In all, 25 III instar larvae of An. stephensi were exposed to various concen...

  20. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae) to Temephos in Malarious Areas of Iran

    OpenAIRE

    Aboozar Soltani; Hassan Vatandoost; Mohammad Ali Oshaghi; Ahmad Ali Enayati; Ahmad Raeisi; Mohammad Reza Eshraghian; Mohammad Mehdi Soltan-Dallal; Ahmad Ali Hanafi-Bojd; Mohammad Reza Abai; Fatemeh Rafi

    2013-01-01

    Background: Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistance Methods: Eight different localities in two main malarious provinces were determined as field collecting sites. Mosquitoes were collected from the field and reared i...

  1. Remotely-sensed land use patterns and the presence of Anopheles larvae (Diptera: Culicidae) in Sukabumi, West Java, Indonesia.

    Science.gov (United States)

    Stoops, Craig A; Gionar, Yoyo R; Shinta; Sismadi, Priyanto; Rachmat, Agus; Elyazar, Iqbal F; Sukowati, Supratman

    2008-06-01

    Land use patterns and the occurrence of Anopheles species larvae were studied in Sukabumi District, West Java, Indonesia, from October 2004 to September 2005. Two land use maps derived using remote sensing were used. One map derived from Quickbird satellite images of 150 km2 of the Simpenan and Ciemas subdistricts (106 degrees 27' 53"-106 degrees 38' 38" E and 6 degrees 59' 59"-7 degrees 8' 46" S) in Sukabumi and one using ASTER images covering 4,000 km2 of Sukabumi District from 106 degrees 22' 15"-107 degrees 4' 1" E and 6 degrees 42' 50" - 7 degrees 26' 13" S. There was a total of 11 Anopheles spp. collected from 209 sampling locations in the area covered by the Quickbird image and a total of 15 Anopheles spp. collected from 1,600 sampling locations in the area covered by the ASTER map. For the area covered by the land use maps, ten species were found to have statistically positive relationships between land use class and species presence: Anopheles aconitus, An. annularis, An. barbirostris. An. flavirostris, An. insulaeflorum, An. kochi, An. maculatus, An. subpictus, An. sundaicus, and An. vagus. Quickbird and ASTER satellite images both produced land maps that were adequate for predicting species presence in an area. The land use classes associated with malaria vector breeding were rice paddy (An. aconitus, An. subpictus), plantation located near or adjacent to human settlements (An. maculatus), bush/shrub (An. aconitus, An. maculatus, An. sundaicus), bare land, and water body land use on the coast located < or = 250 m of the beach (An. sundaicus). Understanding the associations of habitat and species in one area, predictions of species presence or absence can be made prior to a ground survey allowing for accurate vector survey and control planning.

  2. Effect of larval environment on some life history parameters in anopheles gambiae s.s. (diptera:culicidae))

    OpenAIRE

    Jannat, Khandaker Noore

    2010-01-01

    The effects of larval density, nutrition and cannibalism risk on some life history parameters of Anopheles gambiae larvae were evaluated in the laboratory. Adult body size was inversely correlated with larval density whereas larval mortality and mean age at pupation varied across experiments. When density increased, the secondary sex ratio shifted toward female bias. Effects of different types of nutrition on larval life were compared by providing larvae with algae Chaetophora sp., fish food ...

  3. Larvicidal potential of carvacrol and terpinen-4-ol from the essential oil of Origanum vulgare (Lamiaceae) against Anopheles stephensi, Anopheles subpictus, Culex quinquefasciatus and Culex tritaeniorhynchus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Hoti, S L; Benelli, Giovanni

    2016-02-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. However, the use of synthetic insecticides to control Culicidae may lead to resistance, high operational costs and adverse non-target effects. Nowadays, plant-borne mosquitocides may serve as suitable alternative in the fight against mosquito vectors. In this study, the mosquito larvicidal activity of Origanum vulgare (Lamiaceae) leaf essential oil (EO) and its major chemical constituents was evaluated against the malaria vectors Anopheles stephensi and An. subpictus, the filariasis vector Culex quinquefasciatus and the Japanese encephalitis vector Cx. tritaeniorhynchus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the essential oil of O. vulgare contained 17 compounds. The major chemical components were carvacrol (38.30%) and terpinen-4-ol (28.70%). EO had a significant toxic effect against early third-stage larvae of An. stephensi, An. subpictus, Cx. quinquefasciatus and Cx. tritaeniorhynchus, with LC50 values of 67.00, 74.14, 80.35 and 84.93 μg/ml. The two major constituents extracted from the O. vulgare EO were tested individually for acute toxicity against larvae of the four mosquito vectors. Carvacrol and terpinen-4-ol appeared to be most effective against An. stephensi (LC50=21.15 and 43.27 μg/ml, respectively) followed by An. subpictus (LC50=24.06 and 47.73 μg/ml), Cx. quinquefasciatus (LC50=26.08 and 52.19 μg/ml) and Cx. tritaeniorhynchus (LC50=27.95 and 54.87 μg/ml). Overall, this research adds knowledge to develop newer and safer natural larvicides against malaria, filariasis and Japanese encephalitis mosquito vectors. PMID:26850541

  4. Identification, characterisation, and function of adipokinetic hormones and receptor in the African malaria mosquito, "Anopheles Gambiae" (Diptera)

    OpenAIRE

    Kaufmann, Christian; Betschart, Bruno

    2007-01-01

    En utilisant la bioinformatique et la biologie moléculaire, nous avons pu identifier chez le principal vecteur africain de la malaria, le moustique, Anopheles gambiae deux hormones adipokinétiques (AKHs): l'octapeptide, Anoga-AKH-I (pQLTFTPAWa) et le décapeptide, Anoga-AKH-II, (pQVTFSRDWNAa). La fonction principale des AKHs est d’induire une hyperlipémie (effet d’adipokinétique), ainsi qu’une hypertrehalosémie et une hyperprolinémie. En tant que membres de la famille des AKH, les deux neurope...

  5. Repellent activities of stereoisomers of p-menthane-3,8-diols against Anopheles gambiae (Diptera: Culicidae).

    Science.gov (United States)

    Barasa, Stephen S; Ndiege, Isaiah O; Lwande, Wilber; Hassanali, Ahmed

    2002-09-01

    Four stereoisomers of p-menthane-3,8-diol, which make up the natural product obtained from Eucalyptus citriodora, were synthesized through stereoselective procedures. Repellency assays showed that all the four were equally active against Anopheles gambiae s.s. Racemic blends and the diastereoisomeric mixture of all the four isomers were also equally repellent. 1-alpha-terpeneol, with a single hydroxyl function at C-8 and unsaturation at C-8, and menthol, with a single hydroxyl function at C-3, were not repellent. The practical implication of these results is discussed. PMID:12349856

  6. Predators of Anopheles gambiae sensu lato (Diptera: Culicidae) Larvae in Wetlands, Western Kenya: Confirmation by Polymerase Chain Reaction Method

    OpenAIRE

    Ohba, Shin-ya; Kawada, Hitoshi; Dida, Gabriel O; Juma, Duncan; SONYE, GORGE; Minakawa, Noboru; Takagi, Masahiro

    2010-01-01

    Polymerase chain reaction analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%)....

  7. Predators of Anopheles gambiae sensu lato (Diptera: Culicidae) larvae in Wetlands, Western Kenya: Confirmation by polymerase chain reaction method

    OpenAIRE

    Ohba, Shin-ya; Kawada, Hitoshi; Dida, Gabriel O; Juma, Duncan; SONYE, GORGE; Minakawa, Noboru; Takagi, Masahiro

    2010-01-01

    Polymerase chain reaction analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%)....

  8. Salivary Gland Proteome during Adult Development and after Blood Feeding of Female Anopheles dissidens Mosquitoes (Diptera: Culicidae)

    Science.gov (United States)

    Phattanawiboon, Benjarat; Jariyapan, Narissara; Mano, Chonlada; Roytrakul, Sittiruk; Paemanee, Atchara; Sor-Suwan, Sriwatapron; Sriwichai, Patchara; Saeung, Atiporn; Bates, Paul A.

    2016-01-01

    Understanding changes in mosquito salivary proteins during the time that sporozoite maturation occurs and after blood feeding may give information regarding the roles of salivary proteins during the malarial transmission. Anopheles dissidens (formerly Anopheles barbirostris species A1) is a potential vector of Plasmodium vivax in Thailand. In this study, analyses of the proteomic profiles of female An. dissidens salivary glands during adult development and after blood feeding were carried out using two-dimensional gel electrophoresis coupled with nano-liquid chromatography-mass spectrometry. Results showed at least 17 major salivary gland proteins present from day one to day 21 post emergence at 8 different time points sampled. Although there was variation observed, the patterns of protein expression could be placed into one of four groups. Fifteen protein spots showed significant depletion after blood feeding with the percentages of the amount of depletion ranging from 8.5% to 68.11%. The overall results identified various proteins, including a putative mucin-like protein, an anti-platelet protein, a long form D7 salivary protein, a putative gVAG protein precursor, a D7-related 3.2 protein, gSG7 salivary proteins, and a gSG6 protein. These results allow better understanding of the changes of the salivary proteins during the adult mosquito development. They also provide candidate proteins to investigate any possible link or not between sporozoite maturation, or survival of skin stage sporozoites, and salivary proteins. PMID:27669021

  9. Morphology of the larvae, male genitalia and DNA sequences of Anopheles (Kerteszia pholidotus (Diptera: Culicidae from Colombia

    Directory of Open Access Journals (Sweden)

    Jesús Eduardo Escovar

    2014-07-01

    Full Text Available Since 1984, Anopheles (Kerteszia lepidotus has been considered a mosquito species that is involved in the transmission of malaria in Colombia, after having been incriminated as such with epidemiological evidence from a malaria outbreak in Cunday-Villarrica, Tolima. Subsequent morphological analyses of females captured in the same place and at the time of the outbreak showed that the species responsible for the transmission was not An. lepidotus, but rather Anopheles pholidotus. However, the associated morphological stages and DNA sequences of An. pholidotus from the foci of Cunday-Villarrica had not been analysed. Using samples that were caught recently from the outbreak region, the purpose of this study was to provide updated and additional information by analysing the morphology of female mosquitoes, the genitalia of male mosquitoes and fourth instar larvae of An. pholidotus, which was confirmed with DNA sequences of cytochrome oxidase I and rDNA internal transcribed spacer. A total of 1,596 adult females were collected in addition to 37 larval collections in bromeliads. Furthermore, 141 adult females, which were captured from the same area in the years 1981-1982, were analysed morphologically. Ninety-five DNA sequences were analysed for this study. Morphological and molecular analyses showed that the species present in this region corresponds to An. pholidotus. Given the absence of An. lepidotus, even in recent years, we consider that the species of mosquitoes that was previously incriminated as the malaria vector during the outbreak was indeed An. pholidotus, thus ending the controversy.

  10. [Malaria mosquitoes (Diptera, Culicidae, Anopheles) of North Tajikistan, their ecology, and role in the transmission of malaria pathogens].

    Science.gov (United States)

    Kadamov, D S; Zvantseva, A B; Karimov, S S; Gordeev, M I; Goriacheva, I I; Ezhov, M N; Tadzhiboev, A

    2012-01-01

    Five species of malaria mosquitoes: An. artemievi, An. claviger, An. hyrcanus, An. superpictus, and An. pulcherrimus were found in North Tajikistan in 2006 - 2007. Species affiliation was identified according to the morphological signs of their larvae and imagoes, and by using the polymerase chain reaction-restriction fragment length polymorphism analysis. There was a larger number of An. hyrcanus (34%), An. artemievi (29%), and An. pulcherrimus (24%) and a smaller number of An. superpictus (11%); and An. claviger was few (2%). The hatching sites of the above species and the preferred types of their day refuges were found. The intensity of attack of different Anopheles species on humans and animals was studied. Among the North Tajikistan malaria mosquitoes, An. pulcherrimus and An. superpictus are of the greatest epidemiological importance as vehicles for transmission of malaria pathogens. An. artemievi and An. hyrcanus are minor vehicles. At present, An. claviger is of no epidemiological significance in transmitting malaria in North Tajikistan.

  11. Predators of Anopheles gambiae sensu lato (Diptera: Culicidae) larvae in wetlands, western Kenya: confirmation by polymerase chain reaction method.

    Science.gov (United States)

    Ohba, Shin-Ya; Kawada, Hitoshi; Dida, Gabriel O; Juma, Duncan; Sonye, Gorge; Minakawa, Noboru; Takagi, Masahiro

    2010-09-01

    Polymerase chain reaction analysis was performed to determine whether mosquito predators in wetland habitats feed on Anopheles gambiae sensu lato (s.l.) larvae. Aquatic mosquito predators were collected from six wetlands near Lake Victoria in Mbita, Western Kenya. This study revealed that the whole positive rate of An. gambiae s.l. from 330 predators was 54.2%. The order of positive rate was the highest in Odonata (70.2%), followed by Hemiptera (62.8%), Amphibia (41.7%), and Coleoptera (18%). This study demonstrates that the polymerase chain reaction method can determine whether aquatic mosquito predators feed on An. gambiae s.l. larvae if the predators have undigested An. gambiae s.l. in their midgut or stomach. PMID:20939371

  12. Mosquito adulticidal and repellent activities of botanical extracts against malarial vector,Anopheles stephensi Liston (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan; Rajamohan Sivakumar

    2011-01-01

    Objective:To determine the adulticidal and repellent activities of different solvent leaf extracts ofEclipta alba (E. alba) andAndrographis paniculata (A. paniculata)against malarial vector, Anopheles stephensi (An. stephensi).Methods:Adulticidal efficacy of the crude leaf extracts ofE. alba andA. paniculata with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the five to six day old adult female mosquitoes of An. stephensi. The adult mortality was observed after24 h under the laboratory conditions. The repellent efficacy was determined againstAn. stephensimosquito species at three concentrations viz.,1.0, 2.5 and 5.0 mg/cm2 under laboratory conditions.Results: Among the tested solvents the maximum efficacy was observed in the methanol extract. TheLC50 andLC90 values ofE. alba andA. paniculata against adults ofAn. stephensiwere150.36, 130.19 ppm and285.22, 244.16ppm, respectively. No mortality was observed in controls. Thechi-square values were significant at P<0.05 level. Methanol extract of E. alba andA. paniculata was produce maximum repellency againstAn. stephensi.Conclusions:From the results it can be concluded the crude extract ofE. alba andA. paniculatawas an excellent potential for controllingAn. stephensimosquitoes.

  13. Deforestation and Malaria on the Amazon Frontier: Larval Clustering of Anopheles darlingi (Diptera: Culicidae) Determines Focal Distribution of Malaria.

    Science.gov (United States)

    Barros, Fábio S M; Honório, Nildimar A

    2015-11-01

    We performed bimonthly mosquito larval collections during 1 year, in an agricultural settlement in the Brazilian Amazon, as well as an analysis of malaria incidence in neighboring houses. Water collections located at forest fringes were more commonly positive for Anopheles darlingi larvae and Kulldorff spatial analysis pinpointed significant larval clusters at sites directly beneath forest fringes, which were called larval "hotspots." Remote sensing identified 43 "potential" hotspots. Sampling of these areas revealed an 85.7% positivity rate for A. darlingi larvae. Malaria was correlated with shorter distances to potential hotpots and settlers living within 400 m of potential hotspots had a 2.60 higher risk of malaria. Recently arrived settlers, usually located closer to the tip of the triangularly shaped deforestation imprints of side roads, may be more exposed to malaria due to their proximity to the forest fringe. As deforestation progresses, transmission decreases. However, forest remnants inside deforested areas conferred an increased risk of malaria. We propose a model for explaining frontier malaria in the Amazon: because of adaptation of A. darlingi to the forest fringe ecotone, humans are exposed to an increased transmission risk when in proximity to these areas, especially when small dams are created on naturally running water collections. PMID:26416110

  14. Green chemistry focus on optimization of silver nanoparticles using response surface methodology (RSM) and mosquitocidal activity: Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Ondari Nyakundi, Erick; Padmanabhan, M Nalini

    2015-01-01

    There is an exigent necessity for development of environmental friendly bio-control agent(s) for elimination of mosquito due to increased resistance resurgence against synthetic control agents. Mosquito control strategy will lay a strong foundation to malaria exclusion or it can be curbed to certain level especially in the developing nations. In this study, silver nanoparticles were synthesized by green chemistry approach using Tridax procumbens leaf extract as a reducing agent. The reaction medium involved in the synthesis process was optimized by statistical experimental design using response surface methodology to obtain better yield, uniform size, shape and stability. Further, these synthesized nanoparticles were confirmed through UV-Visible, FT-IR spectroscopy, PSA and SEM Subsequently, the bioefficacy of these particles were investigated on Anopheles stephensi for larvicidal and pupicidal activity. Interestingly, time period of 90 min, temperature of 76±2 °C, pH 7.2±2, 2 mM silver nitrate (AgNO3), 3mM PEG and 2mM PVP showed excellent parameters for bioprocess design for large scale production of stabilized nanoparticles. A concentration of 5 ppm of PVP stabilized nanoparticles exhibited 100% mortality. Thus, the obtained results clearly suggest that silver nanoparticles stabilized by PEG and PVP may have important function as stabilizers, dispersants as well as larvicides for mosquito control.

  15. Correlation of survival rates of Anopheles dirus A (Diptera: Culicidae) with different infection densities of Plasmodium cynomolgi*

    Science.gov (United States)

    Klein, T. A.; Harrison, B. A.; Grove, J. S.; Dixon, S. V.; Andre, R. G.

    1986-01-01

    The survival rates are described for 36 paired replicates of Anopheles dirus A mosquitos that had been allowed to engorge themselves on rhesus monkeys that were either infected or non-infected with Plasmodium cynomolgi. The survival rates of infected mosquitos with a mean number of oocysts less than 10 did not differ significantly from those that were non-infected; however, there was a significant difference in the survival rates of non-infected groups and those with a mean number of oocysts in the range 10-40, 41-70, or ≥71. Daily survival rates for non-infected and infected mosquitos did not differ significantly during the first 8 days of extrinsic incubation. In contrast, for the period 9-30 days the survival rates of mosquitos with mean number of oocysts ≥41 were significantly different from those of non-infected mosquitos. The cumulative daily survival rates of mosquitos with mean number of oocysts up to 40, 41-70, or ≥71 decreased with the oocyst count. Mosquitos with a mean number of oocysts ≥71 frequently exhibited excessive numbers of bacteria and deterioration of both their guts and salivary glands. PMID:3493859

  16. STATUS OF INSECTICIDE RESISTANCE IN ANOPHELES CULICIFACIES (DIPTERA: CULICIDAE IN GHASREGHAND DISTRICT, SISTAN AND BALUCHISTAN PROVINCE, IRAN, (1997

    Directory of Open Access Journals (Sweden)

    H. Vatandoost

    1999-08-01

    Full Text Available Anopheles culicifacies s.l. plays an important role In transmission of malaria in Sistan and Baluchistan province, southeastern Iran. Adult susceptibility test on fieltt-collccled mosquitoes was conducted in Ohasreghand district. WHO diagnostic test procedures revealed that adult females were resistant to 0.4% dieUirin (mortality 64.5 ± 3.13, tolerant to 0.1% propoxur (mortality 88.5 ± 2.24 and susceptible to 4% DDT (mortality 98.75 ± 0.8. 5% malathion (mortality 100%, 0.1% bendiocarb (mortality 98.86 ± 0.7, 0.25% pcrmcthrin (mortality 98.4 ± 0.1, ami 0.1% lamhdacyhalothrin (mortality 100%. Malathion and lamhdacyhalothrin had the highest efficacy against this species when they were exposed at the diagnostic dose for 1 hour followed by a 24 hour recovery period. DieUirin, DDT a nil malathion had been used for malaria control as an indoor residual spraying. Tlic implication of these findings in the control programme is discussed.

  17. A molecular phylogeny of Anopheles annulipes (Diptera: Culicidae) sensu lato: the most species-rich anopheline complex.

    Science.gov (United States)

    Foley, D H; Wilkerson, R C; Cooper, R D; Volovsek, M E; Bryan, J H

    2007-04-01

    The Australasian Annulipes Complex is the most species-rich among Anopheles mosquitoes, with at least 15 sibling species suspected. Members of this complex are the most likely vectors of malaria in the past in southern Australia and are involved in the spread of myxomatosis among rabbits. In this, the first comprehensive molecular study of the Annulipes Complex, 23 ITS2 rDNA variants were detected from collections throughout Australia and Papua New Guinea, including diagnostic variants for the previously identified An. annulipes species A-G. Specimens of each ITS2 variant were sequenced for portions of the mitochondrial COI, COII and nuclear EF-1alpha genes. Partitioned Bayesian and Maximum Parsimony analyses confirmed the monophyly of the Annulipes Complex and revealed at least 17 clades that we designate species A-Q. These species belong to two major clades, one in the north and one mainly in the south, suggesting that climate was a driver of species radiation. We found that 65% (11) of the 17 sibling species recorded here had unique COI sequences, suggesting that DNA barcoding will be useful for diagnosing species within the Annulipes Complex. A comparison of the taxa revealed morphological characters that may be diagnostic for some species. Our results substantially increase the size of the subgenus Cellia in Australasia, and will assist species-level studies of the Annulipes Complex. PMID:17126567

  18. Orientation of Anopheles gambiae (Diptera: Culicidae) to Plant-Host Volatiles in a Novel Diffusion-Cage Olfactometer.

    Science.gov (United States)

    Otienoburu, Philip E; Nikbakhtzadeh, Mahmood R; Foster, Woodbridge A

    2016-01-01

    A novel diffusion-cage olfactometer tested the responses of Anopheles gambiae Giles to plant volatiles. Green-leaf volatiles are often released from cut or injured plant tissue and may alter the headspace of plants used in olfactometer assays. The diffusion-cage olfactometer is designed for use with whole, intact plants, hence giving a more realistic behavioral assay. Its simple plastic construction, ease of assembly, and accommodation to whole plants makes it a useful tool for measuring mosquito orientation to plant volatiles within large enclosures. We compared its performance to that of the more commonly used T-tube wind-tunnel olfactometer, by testing the orientation of mosquitoes to volatiles of a few prevalent plants of eastern Africa reportedly utilized by An. gambiae for sugar: Parthenium hysterophorus (Asteraceae), Ricinus communis (Euphorbiaceae), Lantana camara (Verbenaceae), and Senna occidentalis (Fabaceae). Results indicate that the diffusion-cage olfactometer is an effective alternative to conventional wind-tunnel olfactometers, to test mosquito orientation to plant volatiles under seminatural conditions. PMID:26502752

  19. Green chemistry focus on optimization of silver nanoparticles using response surface methodology (RSM) and mosquitocidal activity: Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Ondari Nyakundi, Erick; Padmanabhan, M Nalini

    2015-01-01

    There is an exigent necessity for development of environmental friendly bio-control agent(s) for elimination of mosquito due to increased resistance resurgence against synthetic control agents. Mosquito control strategy will lay a strong foundation to malaria exclusion or it can be curbed to certain level especially in the developing nations. In this study, silver nanoparticles were synthesized by green chemistry approach using Tridax procumbens leaf extract as a reducing agent. The reaction medium involved in the synthesis process was optimized by statistical experimental design using response surface methodology to obtain better yield, uniform size, shape and stability. Further, these synthesized nanoparticles were confirmed through UV-Visible, FT-IR spectroscopy, PSA and SEM Subsequently, the bioefficacy of these particles were investigated on Anopheles stephensi for larvicidal and pupicidal activity. Interestingly, time period of 90 min, temperature of 76±2 °C, pH 7.2±2, 2 mM silver nitrate (AgNO3), 3mM PEG and 2mM PVP showed excellent parameters for bioprocess design for large scale production of stabilized nanoparticles. A concentration of 5 ppm of PVP stabilized nanoparticles exhibited 100% mortality. Thus, the obtained results clearly suggest that silver nanoparticles stabilized by PEG and PVP may have important function as stabilizers, dispersants as well as larvicides for mosquito control. PMID:26010566

  20. Comparison of the Insecticidal Characteristics of Commercially Available Plant Essential Oils Against Aedes aegypti and Anopheles gambiae (Diptera: Culicidae).

    Science.gov (United States)

    Norris, Edmund J; Gross, Aaron D; Dunphy, Brendan M; Bessette, Steven; Bartholomay, Lyric; Coats, Joel R

    2015-09-01

    Aedes aegypti and Anopheles gambiae are two mosquito species that represent significant threats to global public health as vectors of Dengue virus and malaria parasites, respectively. Although mosquito populations have been effectively controlled through the use of synthetic insecticides, the emergence of widespread insecticide-resistance in wild mosquito populations is a strong motivation to explore new insecticidal chemistries. For these studies, Ae. aegypti and An. gambiae were treated with commercially available plant essential oils via topical application. The relative toxicity of each essential oil was determined, as measured by the 24-h LD(50) and percentage knockdown at 1 h, as compared with a variety of synthetic pyrethroids. For Ae. aegypti, the most toxic essential oil (patchouli oil) was ∼1,700-times less toxic than the least toxic synthetic pyrethroid, bifenthrin. For An. gambiae, the most toxic essential oil (patchouli oil) was ∼685-times less toxic than the least toxic synthetic pyrethroid. A wide variety of toxicities were observed among the essential oils screened. Also, plant essential oils were analyzed via gas chromatography/mass spectrometry (GC/MS) to identify the major components in each of the samples screened in this study. While the toxicities of these plant essential oils were demonstrated to be lower than those of the synthetic pyrethroids tested, the large amount of GC/MS data and bioactivity data for each essential oil presented in this study will serve as a valuable resource for future studies exploring the insecticidal quality of plant essential oils.

  1. Monoclonal antibodies AC-43 and AC-29 disrupt Plasmodium vivax development in the Indian malaria vector Anopheles culicifacies (Diptera: culicidae)

    Indian Academy of Sciences (India)

    Manoj Chugh; B R Gulati; S K Gakhar

    2010-03-01

    A repertoire of monoclonal antibodies (mAbs) was generated against the midgut proteins of Anopheles culicifacies mosquitoes. The mAbs AC-43 and AC-29 significantly inhibited Plasmodium vivax development inside the mosquito midgut. The number of oocysts that developed was reduced by 78.6% when mosquitoes ingested a combination of these two mAbs along with the blood meal. AC-43 mAb binds to the epitope common in 97, 80 and 43 kDa polypeptides from the midgut protein extract, as indicated by western blot analysis. Similarly, the mAb AC-29 recognized 52, 44, 40 and 29 kDa polypeptides. These female midgut-specific polypeptides are shared between An. culicifacies and An. stephensi, two major vectors of malaria in India. Deglycosylation assays revealed that -linked carbohydrates are the major components in epitopes corresponding to AC-43 and AC-29. Gold particle labelling revealed that both these mAbs preferentially bind to glycoproteins at the apical microvilli and the microvillus-associated network present inside transverse sections of the gut epithelium. These regions are particularly known to have receptors for ookinetes, which enable them to cross this epithelial barrier and provide them with certain necessary chemicals or components for further development into oocysts. Therefore, these glycoproteins appear to be potential candidates for a vectordirected transmission-blocking vaccine (TBV).

  2. Laboratory studies on the olfactory behaviour of Anopheles quadriannulatus

    NARCIS (Netherlands)

    Pates, H.V.; Takken, W.; Curtis, C.F.

    2005-01-01

    The host preference of Anopheles quadriannulatus Theobald (Diptera: Culicidae), the zoophilic member of the malaria mosquito complex Anopheles gambiae Giles, was investigated in a dual-choice olfactometer. Naïve female mosquitoes were exposed to CO2, acetone, 1-octen-3-ol, and skin emanations from c

  3. Using remote sensing to map larval and adult populations of Anopheles hyrcanus (Diptera: Culicidae a potential malaria vector in Southern France

    Directory of Open Access Journals (Sweden)

    Roger François

    2008-02-01

    Full Text Available Abstract Background Although malaria disappeared from southern France more than 60 years ago, suspicions of recent autochthonous transmission in the French Mediterranean coast support the idea that the area could still be subject to malaria transmission. The main potential vector of malaria in the Camargue area, the largest river delta in southern France, is the mosquito Anopheles hyrcanus (Diptera: Culicidae. In the context of recent climatic and landscape changes, the evaluation of the risk of emergence or re-emergence of such a major disease is of great importance in Europe. When assessing the risk of emergence of vector-borne diseases, it is crucial to be able to characterize the arthropod vector's spatial distribution. Given that remote sensing techniques can describe some of the environmental parameters which drive this distribution, satellite imagery or aerial photographs could be used for vector mapping. Results In this study, we propose a method to map larval and adult populations of An. hyrcanus based on environmental indices derived from high spatial resolution imagery. The analysis of the link between entomological field data on An. hyrcanus larvae and environmental indices (biotopes, distance to the nearest main productive breeding sites of this species i.e., rice fields led to the definition of a larval index, defined as the probability of observing An. hyrcanus larvae in a given site at least once over a year. Independent accuracy assessments showed a good agreement between observed and predicted values (sensitivity and specificity of the logistic regression model being 0.76 and 0.78, respectively. An adult index was derived from the larval index by averaging the larval index within a buffer around the trap location. This index was highly correlated with observed adult abundance values (Pearson r = 0.97, p An. hyrcanus larval and adult populations from the landscape indices. Conclusion This work shows that it is possible to use

  4. DNA Barcodes indicate members of the Anopheles fluviatilis (Diptera: Culicidae) species complex to be conspecific in India.

    Science.gov (United States)

    Pradeep Kumar, N; Krishnamoorthy, N; Sahu, S S; Rajavel, A R; Sabesan, S; Jambulingam, P

    2013-05-01

    Anopheles fluviatilis, a major vector of malaria in India has been described as a complex of three sibling species members, named as S, T and U, based on variations in chromosomal inversions. Also, ribosomal DNA markers (repetitive Internal Transcribed Spacer 2 (ITS2) and 28S D3 region) were described to differentiate these three sibling species members. However, controversies prevail on the genetic isolation status of these cryptic species. Hence, we evaluated this taxonomic incongruence employing DNA barcoding, the well established methodology for species identification, using 60 An. fluviatilis sensu lato specimens, collected from two malaria endemic eastern states of India. These specimens were also subjected to sibling species characterization by ITS2 and D3 DNA markers. The former marker identified 31 specimens among these as An. fluviatilis S and 21 as An. fluviatilis T. Eight specimens amplified DNA fragments specific for both S and T. The D3 marker characterized 39 specimens belonging to species S and 21 to species T. Neither marker identified species U. Neighbor Joining analysis of mitochondrial cytochrome c oxidase gene 1 sequences (the DNA barcode) categorized all the 60 specimens into a single operational taxonomic unit, their Kimura 2 parameter (K2P) genetic variability being only 0.8%. The genetic differentiation (FST ) and gene flow (Nm ) estimates were 0.00799 and 62.07, respectively, indicating these two 'species' (S & T) as genetically con-specific intermixing populations with negligible genetic differentiation. Earlier investigations have refuted the existence of species U. Also, this study demonstrated that An. fluviatilis and the closely related An. minimus could be taxonomically differentiated by the DNA Barcode approach (K2P = 5.0%). PMID:23398631

  5. Larvicidal and repellent properties of Adansonia digitata against medically important human malarial vector mosquito Anopheles stephensi (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    K. Krishnappa , K. Elumalai , S. Dhanasekaran & J. Gokulakrishnan

    2012-06-01

    Full Text Available Background & objectives: Development of plant-based alternative compounds for mosquito control has gainedimportance now-a-days, in view of increasing resistance in mosquito vectors to existing insecticides. The larvicidaland repellent activities of benzene, chloroform, hexane and methanol leaf extracts of Indian medicinal plant,Adansonia digitata were investigated against malarial vector, Anopheles stephensi.Methods: In all, 25 III instar larvae of An. stephensi were exposed to various concentrations (30–180 mg/l in thelaboratory by using the standard protocol described by WHO (2005. The larvae were exposed for 24 h andmortalities were subjected to log-probit analysis. Repellent activity of crude leaf extract at the dosages of 2, 4and 6 mg/cm2 was evaluated in a net cage (45 × 30 × 45 cm containing 100 blood starved female mosquitoes ofAn. stephensi using the protocol of WHO (1996.Results: Preliminary phytochemical analysis of A. digitata showed the presence of triterpenoids and saponins.The LC50 and LC90 values of hexane, benzene, chloroform, and methanol extracts of A. digitata against An.stephensi larvae in 24 h were 111.32, 97.13, 88.55, 78.18 and 178.63, 176.19, 168.14, 155.42 mg/l, respectively.The repellent activity of methanol extract was found to be most effective and at higher concentration of 6mg/cm2 benzene, chloroform hexane and methanol extracts provided 100% protection up to 150, 180, 120 and210 min against An. stephensi, respectively.Conclusion: The preliminary study indicated that A. digitata showed larvicidal and repellent activities againstAn. stephensi and could be used for controlling mosquitoes. Further studies are indicated to purify the activecompounds from these plants for developing larvicide and repellents.

  6. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae to Temephos in Malarious Areas of Irana.

    Directory of Open Access Journals (Sweden)

    Aboozar Soltani

    2013-06-01

    Full Text Available Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistance.Eight different localities in two main malarious provinces were determined as field collecting sites. Mosquitoes were collected from the field and reared in an insectray. Susceptibility assays were carried out according to the WHO method. The laboratory reared susceptible Beech-Lab strain was used for comparison. Data were analyzed using Probit analysis to determine LC50 and LC90 values.Susceptibility of An. stephensi to temephos indicated that the LC50 ranged from 0.0022 mg/l to 0.0141 mg/l. Although all field strains were susceptible to temephos, considerable variations in temephos resistance ratios of field strains were noticed from all the localities studied in comparison with the susceptible strain. A low level of resistance ratio was noticed in An. stephensi populations except for the Chabahar strain (RR= 4.27 fold. All field-collected An. stephensi populations exhibited homogeneity to the larvicide except for Bandar Abbas and Hormoodar village strains (P> 0.05%.Due to intensive use of temephos in the neighboring countries and occurrence of resistant to this insecticide in the main malaria vector in the region, insecticide resistance gene may evolve in the populations of An. stephensi. If temephos be applied as a larvicide it should be used judiciously for resistance management, as rotation strategy.

  7. Baseline Susceptibility of Different Geographical Strains of Anopheles stephensi (Diptera: Culicidae to Temephos in Malarious Areas of Iran

    Directory of Open Access Journals (Sweden)

    Aboozar Soltani

    2013-03-01

    Full Text Available Background: Malaria still remains a public health problem in Iran. There are different vector control interventions such as insecticide spraying. The present study was carried out to determine the susceptibility status of Anopheles stephensi larvae to temephos as a national plan for monitoring and mapping of insecticide resistanceMethods: Eight different localities in two main malarious provinces were determined as field collecting sites. Mos­quitoes were collected from the field and reared in an insectray. Susceptibility assays were carried out according to the WHO method. The laboratory reared susceptible Beech-Lab strain was used for comparison. Data were analyzed using Probit analysis to determine LC50 and LC90 values.Results: Susceptibility of An. stephensi to temephos indicated that the LC50 ranged from 0.0022 mg/l to 0.0141 mg/l. Although all field strains were susceptible to temephos, considerable variations in temephos resistance ratios of field strains were noticed from all the localities studied in comparison with the susceptible strain. A low level of resistance ratio was noticed in An. stephensi populations except for the Chabahar strain (RR= 4.27 fold. All field-collected An. stephensi populations exhibited homogeneity to the larvicide except for Bandar Abbas and Hormoodar village strains (P> 0.05%.Conclusion: Due to intensive use of temephos in the neighboring countries and occurrence of resistant to this insec­ticide in the main malaria vector in the region, insecticide resistance gene may evolve in the populations of An. stephensi. If temephos be applied as a larvicide it should be used judiciously for resistance management, as rotation strategy

  8. Present habitat suitability for Anopheles atroparvus (Diptera, Culicidae and its coincidence with former malaria areas in mainland Portugal

    Directory of Open Access Journals (Sweden)

    César Capinha

    2009-05-01

    Full Text Available Malaria was a major health problem in the first half of the 20th Century in mainland Portugal. Nowadays, although the disease is no longer endemic, there is still the risk of future endemic infections due to the continuous occurrence of imported cases and the possibility of transmission in the country by Anopheles atroparvus Van Thiel, 1927. Since vector abundance constitute one of the foremost factors in malaria transmission, we have created several habitat suitability models to describe this vector species’ current distribution. Three different correlative models; namely (i a multilayer perceptron artificial neural network (MLP-ANN; (ii binary logistic regression (BLR; and (iii Mahalanobis distance were used to combine the species records with a set of five environmental predictors. Kappa coefficient values from k-fold cross-validation records showed that binary logistic regression produced the best predictions, while the other two models also produced acceptable results. Therefore, in order to reduce uncertainty, the three suitability models were combined. The resulting model identified high suitability for An. atroparvus in the majority of the country with exception of the northern and central coastal areas. Malaria distribution during the last endemic period in the country was also compared with the combined suitability model, and a high degree of spatial agreement was obtained (kappa = 0.62. It was concluded that habitat suitability for malaria vectors can constitute valuable information on the assessment of several spatial attributes of the disease. In addition, the results suggest that the spatial distribution of An. atroparvus in the country remains very similar to the one known about seven decades ago.

  9. Population genetic structure of the major malaria vector Anopheles darlingi (Diptera: Culicidae from the Brazilian Amazon, using microsatellite markers

    Directory of Open Access Journals (Sweden)

    Vera Margarete Scarpassa

    2007-06-01

    Full Text Available The population genetic structure of Anopheles darlingi, the major human malaria vector in the Neotropics, was examined using seven microsatellite loci from nine localities in central and western Amazonian Brazil. High levels of genetic variability were detected (5-25 alleles per locus; H E = 0.519-0.949. There was deviation from Hardy-Weinberg Equilibrium for 59.79% of the tests due to heterozygote deficits, while the analysis of linkage disequilibrium was significant for only two of 189 (1.05% tests, most likely caused by null alleles. Genetic differentiation (F ST = 0.001-0.095; Nm = 4.7-363.8 indicates that gene flow is extensive among locations < 152 km apart (with two exceptions and reduced, but not absent, at a larger geographic scale. Genetic and geographic distances were significantly correlated (R² = 0.893, P < 0.0002, supporting the isolation by distance (IBD model. The overall estimate of Ne was 202.4 individuals under the linkage disequilibrium model, and 8 under the heterozygote excess model. Analysis of molecular variance showed that nearly all variation (~ 94% was within sample locations. The UPGMA phenogram clustered the samples geographically, with one branch including 5/6 of the state of Amazonas localities and the other branch the Acre, Rondônia, and remaining Amazonas localities. Taken together, these data suggest little genetic structure for An. darlingi from central and western Amazonian Brazil. These findings also imply that the IBD model explains nearly all of the differentiation detected. In practical terms, populations of An. darlingi at distances < 152 km should respond similarly to vector control measures, because of high gene flow.

  10. Expression Profiles and RNAi Silencing of Inhibitor of Apoptosis Transcripts in Aedes, Anopheles, and Culex Mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Puglise, Jason M; Estep, Alden S; Becnel, James J

    2016-03-01

    Effective mosquito control is vital to curtail the devastating health effects of many vectored diseases. RNA interference (RNAi)-mediated control of mosquitoes is an attractive alternative to conventional chemical pesticides. Previous studies have suggested that transcripts for inhibitors of apoptosis (IAPs) may be good RNAi targets. To revisit and extend previous reports, we examined the expression of Aedes aegypti (L.) IAPs (AaeIAPs) 1, 2, 5, 6, 9, and a viral IAP-associated factor (vIAF) as well as Anopheles quadrimaculatus Say and Culex quinquefasciatus Say IAP1 homologs (AquIAP1 and CquIAP1) in adult females. Expression profiles of IAPs suggested that some older female mosquitoes had significantly higher IAP mRNA levels when compared to the youngest ones. Minor differences in expression of AaeIAPs were observed in mosquitoes that imbibed a bloodmeal, but the majority of the time points (up to 48 h) were not significantly different. Although in vitro experiments with the Ae. aegypti Aag-2 cell line demonstrated that the various AaeIAPs could be effectively knocked down within one day after dsRNA treatment, only Aag-2 cells treated with dsIAP1 displayed apoptotic morphology. Gene silencing and mortality were also evaluated after topical application and microinjection of the same dsRNAs into female Ae. aegypti. In contrast to previous reports, topical administration of dsRNA against AaeIAP1 did not yield a significant reduction in gene expression or increased mortality. Knockdown of IAP1 and other IAPs by microinjection did not result in significant mortality. In toto, our findings suggest that IAPs may not be suitable RNAi targets for controlling adult mosquito populations.

  11. Ovicidal and repellent activities of botanical extracts against Culex quinquefasciatus,Aedes aegypti and Anopheles stephensi(Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Govindarajan; M; Mathivanan; T; Elumalai; K; Krishnappa; K; Anandan; A

    2011-01-01

    Objective:To determine the ovicidal and repellent activities of methanol leaf extract of Ervatamia coronaria(E.coronaria) and Caeslpinia pulckerrima(C.pulcherrima) against Culex quinquefasciatus(Cx.quinquefasciatus),Aedes aegypti(Ae.aegypti) and Anopheles stephensi(An. stephensi).Methods:The ovicidal activity was determined against three mosquito species at various concentrations ranging from 50-450 ppm under the laboratory conditions.The hatch rates were assessed 48 h after treatment.The repellent efficacy was determined against three mosquito species at three concentrations viz.,1.0,2.5 and 5.0 mg/cm under the laboratory conditions. Results:The crude extract of E.coronaria exerted zero hatchability(100%mortality) at 250.200 and 150 ppm for Cx.quinqitefasciatus,Ae.aegypti and An.stephensi,respectively.The crude extract of C.pulchenima exerted zero hatchability(100%mortality) at 375.300 and 225 ppm for Cx.quinquefasciatus,Ae.aegypti and An.Stephensi,respectively.The methanol extract of E. coronaria found to be more repellenct than C.pukherrima extract.A higher concentration of 5.0 mg/cm~2 provided 100%protection up to 150.180 and 210 min against Cx.quinquefasciatus,Ae. aegypti and An.stephensi,respectively.The results clearly showed that repellent activity was dose dependent.Conclusions:From the results it can be concluded the crude extracts of E.coronaria and C.pukherrima are an excellent potential for controlling Cx.quinquefasciatus,Ae.aegypti and An.stephensi mosquitoes.

  12. Survival of anopheline eggs and their susceptibility to infection with Metarhizium anisopliae and Beauveria bassiana under laboratory conditions

    NARCIS (Netherlands)

    Luz, C.; Mnyone, L.L.; Russell, T.L.

    2011-01-01

    The viability of Anopheles gambiae sensu stricto and Anopheles arabiensis (Diptera: Culicidae) eggs over time and the ovicidal activity of Beauveria bassiana (Ascomycota: Cordycipitaceae) and Metarhizium anisopliae (Ascomycota: Clavicipitaceae) were investigated. Eggs were incubated in soil or leaf

  13. Anopheles salivary gland proteomes from major malaria vectors

    Directory of Open Access Journals (Sweden)

    Fontaine Albin

    2012-11-01

    Full Text Available Abstract Background Antibody responses against Anopheles salivary proteins can indicate individual exposure to bites of malaria vectors. The extent to which these salivary proteins are species-specific is not entirely resolved. Thus, a better knowledge of the diversity among salivary protein repertoires from various malaria vector species is necessary to select relevant genus-, subgenus- and/or species-specific salivary antigens. Such antigens could be used for quantitative (mosquito density and qualitative (mosquito species immunological evaluation of malaria vectors/host contact. In this study, salivary gland protein repertoires (sialomes from several Anopheles species were compared using in silico analysis and proteomics. The antigenic diversity of salivary gland proteins among different Anopheles species was also examined. Results In silico analysis of secreted salivary gland protein sequences retrieved from an NCBInr database of six Anopheles species belonging to the Cellia subgenus (An. gambiae, An. arabiensis, An. stephensi and An. funestus and Nyssorhynchus subgenus (An. albimanus and An. darlingi displayed a higher degree of similarity compared to salivary proteins from closely related Anopheles species. Additionally, computational hierarchical clustering allowed identification of genus-, subgenus- and species-specific salivary proteins. Proteomic and immunoblot analyses performed on salivary gland extracts from four Anopheles species (An. gambiae, An. arabiensis, An. stephensi and An. albimanus indicated that heterogeneity of the salivary proteome and antigenic proteins was lower among closely related anopheline species and increased with phylogenetic distance. Conclusion This is the first report on the diversity of the salivary protein repertoire among species from the Anopheles genus at the protein level. This work demonstrates that a molecular diversity is exhibited among salivary proteins from closely related species despite their

  14. Synergism between ammonia, lactic acid and carboxylic acids as kairomones in the host-seeking behaviour of the malaria mosquito Anopheles gambiae sensu stricto (Diptera: Culicidae)

    NARCIS (Netherlands)

    Smallegange, R.C.; Qiu, Y.T.; Loon, van J.J.A.; Takken, W.

    2005-01-01

    Host odours play a major role in the orientation and host location of blood-feeding mosquitoes. Anopheles gambiae Giles sensu stricto, which is the most important malaria vector in Africa, is a highly anthropophilic mosquito species, and the host-seeking behaviour of the females of this mosquito is

  15. Evaluation of Methods for Sampling the Malaria Vector Anopheles darlingi (Diptera, Culicidae) in Suriname and the Relation With Its Biting Behavior

    NARCIS (Netherlands)

    Hiwat-van Laar, H.; Rijk, de M.; Andriessen, R.; Koenraadt, C.J.M.; Takken, W.

    2011-01-01

    The effectiveness of CO2-baited and human-baited mosquito traps for the sampling of Anopheles darlingi Root was evaluated and compared with human landing collections in Suriname. Biting preferences of this mosquito on a human host were studied and related to trapping data. Traps used were the Center

  16. Studies on larvicidal and pupicidal activity of Leucas aspera Willd. (Lamiaceae) and bacterial insecticide, Bacillus sphaericus, against malarial vector, Anopheles stephensi Liston (Diptera: Culicidae)

    Science.gov (United States)

    The efficacy of whole plant ethanolic extracts of Leucas aspera and of Bacillus sphaericus was determined for larvae and pupae of Anopheles stephensi. When larvae were exposed to one of five concentrations of plant extract (6%, 8%, 10%, 12%, and 14%) for 24 h, mortality in 4th instars ranged from 1...

  17. Geometric morphometric analysis of Colombian Anopheles albimanus (Diptera: Culicidae) reveals significant effect of environmental factors on wing traits and presence of a metapopulation

    OpenAIRE

    Giovan F Gómez; Márquez, Edna J.; Gutiérrez, Lina A.; Conn, Jan E.; Correa, Margarita M.

    2014-01-01

    Anopheles albimanus is a major malaria mosquito vector in Colombia. In the present study, wing variability (size and shape) in An. albimanus populations from Colombian Maracaibo and Chocó bio-geographical eco-regions and the relationship of these phenotypic traits with environmental factors were evaluated. Microsatellite and morphometric data facilitated a comparison of the genetic and phenetic structure of this species. Wing size was influenced by elevation and relative humidity, whereas win...

  18. Larval habitat associations with human land uses, roads, rivers and land cover for Anopheles albimanus, An. pseudopunctipennis and An. punctimacula (Diptera: Culicidae in coastal and highland Ecuador

    Directory of Open Access Journals (Sweden)

    Lauren Lynn Pinault

    2012-03-01

    Full Text Available Larval habitat for three highland Anopheles species: Anopheles albimanus Wiedemann, Anopheles pseudopunctipennis Theobald, and Anopheles punctimacula Dyar & Knab was related to human land uses, rivers, roads, and remotely sensed land cover classifications in the western Ecuadorian Andes. Of the five commonly-observed human land uses, cattle pasture (n=30 provided potentially suitable habitat for An. punctimacula and An. albimanus in less than 14% of sites, and was related in a Principal Components Analysis (PCA to the presence of macrophyte vegetation, greater surface area, clarity and algae cover. Empty lots (n=30 were related in the PCA to incident sunlight and provided potential habitat for An. pseudopunctipennis and An. albimanus in less than 14% of sites. The other land uses surveyed (banana, sugarcane and mixed tree plantations; n=28, 21, 25, respectively provided very little standing water that could potentially be used for larval habitat. River edges and eddies (n=41 were associated with greater clarity, depth, temperature and algae cover, which provide potentially suitable habitat for An. albimanus in 58% of sites and An. pseudopunctipennis in 29% of sites. Road-associated water bodies (n=38 provided potential habitat for An. punctimacula in 44% of sites and An. albimanus in 26% of sites surveyed. Species collection localities were compared to land cover classifications using Geographic Information Systems software. All three mosquito species were associated more often with the category "closed/open broadleaved evergreen and/or semi-deciduous forests" than expected (P ≤ 0.01 in all cases, given such a habitat's abundance. This study provides evidence that specific human land uses create habitat for potential malaria vectors in highland regions of the Andes.

  19. Preliminary field testing of a long-lasting insecticide-treated hammock against Anopheles gambiae and Mansonia spp. (Diptera : Culicidae) in West Africa

    OpenAIRE

    Hougard, Jean-Marc; Martin, Thibaud; Guillet, Pierre; Coosemans, M.; ITOH, T.; Akogbéto, M.; Chandre, Fabrice

    2007-01-01

    The efficacy of an experimental long-lasting insecticide-treated ham mock (LLIH) with a long-lasting treated net used as a blanket and made of the same fabric (polyethylene) was tested in a concrete block experimental hut, against the malaria vector Anopheles gambiae s.l. and the arbovirus vectors and nuisance mosquitoes Mansonia africana (Theobald) and Alansonia uniformis (Theobald). The LLIH was treated with the pyrethroid insecticide permethrin. It was evaluated concurrently with ignited m...

  20. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

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    Forattini Oswaldo Paulo

    1994-01-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  1. Molecular species identification, host preference and detection of myxoma virus in the Anopheles maculipennis complex (Diptera: Culicidae) in southern England, UK.

    OpenAIRE

    Brugman, VA; Hernández-Triana, LM; Prosser, SW; Weland, C; Westcott, DG; Fooks, AR; Johnson, N

    2015-01-01

    Background Determining the host feeding patterns of mosquitoes by identifying the origin of their blood-meals is an important part of understanding the role of vector species in current and future disease transmission cycles. Collecting large numbers of blood-fed mosquitoes from the field is difficult, therefore it is important to maximise the information obtained from each specimen. This study aimed to use mosquito genome sequence to identify the species within Anopheles maculipennis sensu l...

  2. Studies on mosquitoes (Diptera: Culicidae and anthropicenvironment: 5- Breeding of Anopheles albitarsis in flooded rice fields in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1994-10-01

    Full Text Available Studies on breeding Anopheles albitarsis and association with rice growth in irrigated paddy fields were carried out during the rice cultivation cycle from December 1993 to March 1994. This period corresponded to the length of time of permanent paddy flooding. Breeding occurred in the early stage up until five weeks after transplantation when rice plant height was small. That inverse correlation may give potential direction to control measures.

  3. Nigeria Anopheles vector database: an overview of 100 years' research.

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    Patricia Nkem Okorie

    Full Text Available Anopheles mosquitoes are important vectors of malaria and lymphatic filariasis (LF, which are major public health diseases in Nigeria. Malaria is caused by infection with a protozoan parasite of the genus Plasmodium and LF by the parasitic worm Wuchereria bancrofti. Updating our knowledge of the Anopheles species is vital in planning and implementing evidence based vector control programs. To present a comprehensive report on the spatial distribution and composition of these vectors, all published data available were collated into a database. Details recorded for each source were the locality, latitude/longitude, time/period of study, species, abundance, sampling/collection methods, morphological and molecular species identification methods, insecticide resistance status, including evidence of the kdr allele, and P. falciparum sporozoite rate and W. bancrofti microfilaria prevalence. This collation resulted in a total of 110 publications, encompassing 484,747 Anopheles mosquitoes in 632 spatially unique descriptions at 142 georeferenced locations being identified across Nigeria from 1900 to 2010. Overall, the highest number of vector species reported included An. gambiae complex (65.2%, An. funestus complex (17.3%, An. gambiae s.s. (6.5%. An. arabiensis (5.0% and An. funestus s.s. (2.5%, with the molecular forms An. gambiae M and S identified at 120 locations. A variety of sampling/collection and species identification methods were used with an increase in molecular techniques in recent decades. Insecticide resistance to pyrethroids and organochlorines was found in the main Anopheles species across 45 locations. Presence of P. falciparum and W. bancrofti varied between species with the highest sporozoite rates found in An. gambiae s.s, An. funestus s.s. and An. moucheti, and the highest microfilaria prevalence in An. gambiae s.l., An. arabiensis, and An. gambiae s.s. This comprehensive geo-referenced database provides an essential baseline on

  4. "Repellent Effect of Extracts and Essential Oils of Citrus limon (Rutaceae and Melissa officinalis (Labiatae Against Main Malaria Vector, Anopheles stephensi (Diptera: Culicidae"

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    "MA Oshaghi

    2003-10-01

    Full Text Available Repellet effect of extracts and essential oils of Citrus limon (L. Burm.F., (lemon and Melissa officinalis, (balm were evaluated against Anopheles stephensi in laboratory on animal and human and compared with synthetic repellent, N,Ndiethyl- 3-methylbenzamide (Deet as a standard. Results of statistical analysis revealed significant differences between oils and extracts (P< 0.05 against the tested species, thus oils were more effective than extracts. There was no significant difference between Deet and lemon oil, whereas the difference between lemon and melissa oils was significant. Relative efficacy of lemon oil to Deet was 0.88 whereas it was 0.71 for melissa oil. The results were found marginally superior in repellency for animals than human. Due to advantages of botanic compounds to synthetic compounds we recommend lemon essential oil as an effective alternative to Deet with potential as a means of personal protection against mosquito vectors of disease.

  5. Comparison of two commercial formulations of Bacillus thuringiensis var. israelensis for the control of Anopheles aquasalis (Diptera: Culicidae at three salt concentrations

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    Frances R Osborn

    2007-02-01

    Full Text Available Anopheles aquasalis larvae are salt water tolerant, preferring concentrations between 10 and 20 parts per thousand (ppt. The larvicidal efficacy of two formulations of Bacillus thuringiensis var. israelensis (Vectobac-12AS® and Bactivec®, was investigated against An. aquasalis at salinities of 0, 10, and 20 ppt. A probit analysis was used to calculate the lethal concentrations (LC50 and LC95 for each product at each salinity. The LC50 and LC95 were higher for Bactivec® than Vectobac-12AS®, and for Bactivec®, the LC50 and LC95 increased with salinity. Vectobac-12AS® should thus be preferred to Bactivec® for An. aquasalis control, especially in saline breeding habitats.

  6. Effect of anti-mosquito hemolymph antibodies on fecundity and on the infectivity of malarial parasite Plasmodium vivax to Anopheles stephensi (Diptera:Insecta).

    Science.gov (United States)

    Gulia, Monika; Suneja, Amita; Gakhar, Surendra K

    2002-06-01

    Rabbit antibodies to hemolymph antigens (102.5, 101, 100, 96, 88, 80, 64, 55, 43, 29, and 23 kDa) of Anopheles stephensi reduced fecundity as well as viability in An. stephensi. However, ingestion of these antibodies was not associated with a marked effect on the engorgement of mosquitoes but egg laying was significantly delayed. Antisera raised against hemolymph proteins were also used to identify cross reactive antigens/epitopes present in other tissues by Western blotting, as well as by in vivo ELISA. In addition, a significant reduction in oocyst development was also observed in An. stephensi mosquitoes that ingested anti-hemolymph antibodies along with Plasmodium vivax. The results confirmed the feasibility of targeting mosquito antigens as a novel anti-mosquito strategy, as well as confirmed the usefulness of such antigens for the development of a transmission-blocking vaccine. PMID:12195047

  7. Comparative biology and reproductive behaviour of a laboratory-adapted Redco strain of Anopheles Gambiae Giles (Diptera; culicidae and wild populations of the same species

    International Nuclear Information System (INIS)

    The sterile insect technique involves mass rearing of male insects for sterility purpose. This heavily relies on male fitness and genetic compatibility of laboratory-adapted male insects and the wild to ensure successful competition with their male counterpart in the wild. Uniform environment in the laboratory as compared to the wild conditions might lead to genetic drift which might lead to reduced sexual competitiveness, fitness, morphological changes or changes in the sexual behaviour of mosquitoes. This work investigated the sexual compatibility, morphometry and sexual behaviour of laboratory-adapted strain and wild strain of Anopheles gambiae under laboratory conditions. These measurements were done by observing swarm formation, genitalia rotation, percentage insemination, fecundity, fertility, wing length, wing width, thoracic width, body length, body size index and wing size index. Morphometric studies of laboratory-adapted and wild strain of Anopheles gambiae were carried out by observing the wing length, body length and thoracic length under Lecia 4D stereoscope in order to find out variations in the body size between the two strains. The results showed significant difference between thoracic width and wing length between the laboratory-adapted strain and wild strain. Indices such as body size index and wing length index also showed significant difference between the two strains; laboratory-adapted REDCO strain (BSI 4.45 ± 0.10, p = 0.010 ; WSI 1.92 ± 0.07, p = 0.026) and wild REDCO strain ( 4.08 ± 0.10, p = 0.010 ; WSI 1.73 ± 0.04, p = 0.026 ). Body length of laboratory-adapted male mosquitoes (4.24 ± 0.05, p = 0.462) was not significantly different from its thoracic width, wing length, and wing width. The wild strain on the other hand had significant difference between its body length (4.19 ± 0.04, p = 0.462), thoracic width (0.096 ± 0.02, p = 0.002 ) and wing length (2.99 ± 0.03, p = 0.050 ). In the mating experiment, egg production in each of

  8. Revisión histórica de la distribución de Anopheles (Nyssorhynchus darlingi (Diptera: Culicidae en la amazonía peruana

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    Roberto Fernández

    2014-06-01

    Full Text Available Anopheles (Nyssorhynchus darlingi ha sido reportado desde 1931 en áreas fronterizas del departamento de Loreto, principalmente a lo largo de las fronteras con Brasil y Colombia. En 1994, durante un brote de malaria, An. darlingi fue encontrado en localidades vecinas a Iquitos. En la actualidad, su distribución se ha expandido considerablemente en Loreto. Para los objetivos de este trabajo se realizó una revisión de las referencias bibliográficas disponibles para obtener toda la información posible sobre la distribución de los mosquitos, en particular de los anofelinos en la región Amazónica del país, con énfasis especial en An. darlingi. También se realizaron colectas entomológicas en los departamentos de Madre de Dios y Ucayali con la finalidad de conocer y verificar la distribución de An. darlingi. En la actualidad, la distribución de la especie está circunscrita a localidades al sureste del Perú en localidades fronterizas con Bolivia, en una localidad del río Abujao del departamento de Ucayali, y ampliamente en la región noreste de la cuenca amazónica del departamento de Loreto

  9. Revisión histórica de la distribución de Anopheles (Nyssorhynchus darlingi (Diptera: Culicidae en la amazonía peruana

    Directory of Open Access Journals (Sweden)

    Roberto Fernández

    2014-04-01

    Full Text Available Anopheles (Nyssorhynchus darlingi ha sido reportado desde 1931 en áreas fronterizas del departamento de Loreto, principalmente a lo largo de las fronteras con Brasil y Colombia. En 1994, durante un brote de malaria, An. darlingi fue encontrado en localidades vecinas a Iquitos. En la actualidad, su distribución se ha expandido considerablemente en Loreto. Para los objetivos de este trabajo se realizó una revisión de las referencias bibliográficas disponibles para obtener toda la información posible sobre la distribución de los mosquitos, en particular de los anofelinos en la región Amazónica del país, con énfasis especial en An. darlingi. También se realizaron colectas entomológicas en los departamentos de Madre de Dios y Ucayali con la finalidad de conocer y verificar la distribución de An. darlingi. En la actualidad, la distribución de la especie está circunscrita a localidades al sureste del Perú en localidades fronterizas con Bolivia, en una localidad del río Abujao del departamento de Ucayali, y ampliamente en la región noreste de la cuenca amazónica del departamento de Loreto

  10. Mosquitocidal activity of indigenenous plants of Western Ghats, Achras sapota Linn. (Sapotaceae) and Cassia auriculata L. (Fabaceae) against a common malarial vector, Anopheles stephensi Liston (Culicidae:Diptera)

    Institute of Scientific and Technical Information of China (English)

    Kaliyamoorthy Krishnappa; Kuppusamy Elumalai

    2014-01-01

    Objective: To evaluate the mosquito larvicidal, ovicidal, pupicidal and repellent activities of hexane, diethyl ether, dichloromethane, acetone and methanol extracts of Indian medicinal plants, Achras sapota (A. sapota) and Cassia auriculata (C. auriculata) at different concentrations against Anopheles stephensi (An. stephensi), a malarial vector. Methods: Twenty five early third instar larvae of An. stephensi were exposed to various concentrations (30-210 mg/L) of plants extracts and were assayed in the laboratory by using the protocol of WHO 2005;then after 24 h LC50 values of the A. sapota and C. auriculata leaf extract was determined by probit analysis. The ovicidal activity was tested with the extracts ranging from 50-350 mg/L. The pupicidal activity was recorded after 24 h of exposure to the extract. The repellent efficacy was determined against mosquito species at two different concentrations 1.5 and 3.0 mg/cm2 under laboratory conditions. Results:Among the five different extracts tested against the An. stephensi, methanol extract of A. sapota proved to be an more effective solvent extract in almost all the parameters studied than C. auriculata. Conclusions:It is inferred that the leaf extract of A. sapota and C. auriculata could be used in vector control programme.

  11. Production of a Transgenic Mosquito Expressing Circumsporozoite Protein, a Malarial Protein, in the Salivary Gland of Anopheles stephensi (Diptera:Culicidae

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    Matsuoka,Hiroyuki

    2010-08-01

    Full Text Available We are producing a transgenic mosquito, a flying syringe, to deliver a vaccine protein to human beings via the saliva the mosquito deposits in the skin while biting. The mosquito produces a vaccine protein in the salivary gland (SG and deposits the protein into the host's skin when it takes the host's blood. We chose circumsporozoite protein (CSP, currently the most promising malaria vaccine candidate, to be expressed in the SG of Anopheles stephensi. To transform the mosquitoes, plasmid containing the CSP gene under the promoter of female SG-specific gene, as well as the green fluorescent protein (GFP gene under the promoter of 3xP3 as a selection marker in the eyes, was injected into more than 400 eggs. As a result, five strains of GFP-expressing mosquitoes were established, and successful CSP expression in the SG was confirmed in one strain. The estimated amount of CSP in the SG of the strain was 40ng per mosquito. We allowed the CSP-expressing mosquitoes to feed on mice to induce the production of anti-CSP antibody. However, the mice did not develop anti-CSP antibody even after transgenic mosquitoes had bitten them several times. We consider that CSP in the SG was not secreted properly into the saliva. Further techniques and trials are required in order to realize vaccine-delivering mosquitoes.

  12. Insecticidal potential of Ocimum canum plant extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus larval and adult mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Murugan, Jimmantiyur Madhappan; Ramkumar, Govindaraju; Shivakumar, Muthugoundar Subramanian

    2016-01-01

    Mosquitoes have developed resistance to various synthetic insecticides, making their control increasingly difficult. Insecticides of botanical origin may serve as suitable natural control. This study evaluates the toxic potential of Ocimum canum (Sims) leaf extract and powder against Anopheles stephensi (Liston), Aedes aegypti (Lin) and Culex quinquefasciatus (Say) larval and adult mosquitoes. Larval mortality was observed after 24 h recovery period and adult smoke toxicity observed for 40 min duration at 10 min interval. Methanol extract of O. canum showed highest larval mortality against the larvae of C. quinquefasciatus LC50 = 28.3225, LC90 = 44.1150; Ae. aegypti LC50 = 43.327, LC90 = 61.249; and An. stephensi LC50 = 30.2001, LC90 = 48.2866 ppm. The smoke toxicities were 93% mortality in C. quinquefasciatus, 74% in Ae. aegypti and 79% in An. stephensi adults, respectively, whereas 100% mortality was recorded in the commercial mosquito control. Our results suggest that O. canum leaf extract and powder are natural insecticide, and ideal eco friendly approach for mosquito control.

  13. First Record of Anopheles darlingi Root (Diptera, Culicidae in the Volta Grande Environmental Reserve, Conceição das Alagoas Municipality, Minas Gerais, Brazil

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    Rafael Martins

    2015-04-01

    Resumo. Três espécimes de Anopheles darlingi Root foram encontrados na reserva ambiental Volta Grande, na área de influência da barragem do Rio Grande construída pela usina hidrelétrica de Volta Grande, em Conceição das Alagoas, Minas Gerais, Brasil. O mosquito An. darlingi é um dos principais vetores da malária humana no Brasil, devido à sua preferência alimentar por sangue humano, um fator que é acentuado pelo comportamento endofílico da espécie. O presente relato poderá ser útil à vigilância entomológica local para monitoramento dos impactos gerados pela formação do reservatório hidrelétrico, uma vez que a presença deste vetor neste tipo de ambiente indica um risco potencial de transmissão da malária.

  14. The Influence of Insecticide Resistance, Age, Sex, and Blood Feeding Frequency on Thermal Tolerance of Wild and Laboratory Phenotypes of Anopheles funestus (Diptera: Culicidae).

    Science.gov (United States)

    Lyons, C L; Oliver, S V; Hunt, R H; Coetzee, M

    2016-03-01

    Resistance to insecticides is a global phenomenon and is increasing at an unprecedented rate. How resistant and susceptible strains of malaria vectors might differ in terms of life history and basic biology is often overlooked, despite the potential importance of such information in light of changing climates. Here, we investigated the upper thermal limits (ULT50) of wild and laboratory strains of Anopheles funestus Giles mosquitoes, including resistance status, sex, age, and blood feeding status as potential factors influencing ULT50. No significant differences in ULT50 were observed between strains displaying different resistance patterns, nor was there a significant difference between wild and laboratory strains. In some instances, strains showed a senescence response, displaying decreased ULT50 with an increase in age, and differences between males and females (females displaying higher ULT50 than males). Blood feeding did not seem to influence ULT50 in any way. For An. funestus, it seems evident that there is no cost to resistance despite what is displayed in other anopheline species. This could have significant impacts for vector control, with resistant populations of An. funestus performing just as well, if not better, than susceptible strains, especially under changing environmental conditions such as those expected to occur with climate change. PMID:26718714

  15. Transstadial and horizontal transfer of bacteria within a colony of Anopheles gambiae (Diptera: Culicidae) and oviposition response to bacteria-containing water.

    Science.gov (United States)

    Lindh, J M; Borg-Karlson, A-K; Faye, I

    2008-09-01

    In a paratransgenic approach, genetically modified bacteria are utilized to kill the parasite in the vector gut. A critical component for paratransgenics against malaria is how transgenic bacteria can be introduced and then kept in a mosquito population. Here, we investigated transstadial and horizontal transfer of bacteria within an Anopheles gambiae mosquito colony with the focus on spiked breeding sites as a possible means of introducing bacteria to mosquitoes. A Pantoea stewartii strain, previously isolated from An. gambiae, marked with a green fluorescent protein (GFP), was introduced to mosquitoes in different life stages. The following life stages or older mosquitoes in the case of adults were screened for bacteria in their guts. In addition to P. stewartii other bacteria were isolated from the guts: these were identified by 16S rRNA sequence analysis and temporal temperature gradient gel electrophoresis (TTGE). Bacteria were transferred from larvae to pupae but not from pupae to adults. The mosquitoes were able to take up bacteria from the water they emerged from and transfer the same bacteria to the water they laid eggs in. Elizabethkingia meningoseptica was more often isolated from adult mosquitoes than P. stewartii. A bioassay was used to examine An. gambiae oviposition responses towards bacteria-containing solutions. The volatiles emitted from the solutions were sampled by headspace-solid phase microextraction (SPME) and identified by gas chromatography and mass spectrometry (GC-MS) analysis. P. stewartii but not E. meningoseptica mediated a positive oviposition response. The volatiles emitted by P. stewartii include indole and 3-methyl-1-butanol, which previously have been shown to affect An. gambiae mosquito behaviour. E. meningoseptica emitted indole but not 3-methyl-1-butanol, when suspended in saline. Taken together, this indicates that it may be possible to create attractive breeding sites for distribution of genetically modified bacteria in the

  16. Larvicidal,ovicidal and repellent activities of marine sponge Cliona celata(Grant) extracts against Anopheles stephensi Liston(Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Appadurai; Daniel; Reegan; Arokia; Valan; Kinsalin; Michael; Gabriel; Paulraj; Savarimuthu; Ignacimuthu

    2015-01-01

    Obective:To evaluate the larvieidal.ovieidal and repellent properties of solvent extracts of marine sponge Cliona celala(C.celata)(Grant) against the malarial vector Anopheles stephensi(An.stephensi) Listen.Methods:Marine sponge C.celala was thoroughly washed with distilled water and shade dried for 48 h.Then the sponges were homogenized and extracted sequentially with hexane,ethyl acetate and methanol,Lanvicidal and ovicidal activities were tested at four different concentrations viz.,62.5.125.0.250.0 and 500.0 ppm.for repellent study extracts were taken in three different concentrations viz..5.0.2.5.1.0 mg/cm at.Results:Among the three solvent extracts of C.celata,methanol extract showed thc highest lanvieidal activity at 500 ppm against the fourth inslar larvae of An.stephensi.The LC50and LC90 values of C.celata methanol extract were recorded as 80.61 and 220.81 ppm against An.stephensi larvae respectively.High ovieidal activity of 91.2%was recorded al 500 ppm concentration of methanol extract.The haxane extract was found to be the most effective protectant against the adult female mosquitoes of An.stephensi.The mean protection time recorded in hexane extract was up to 245 min at 5 mg/cm2 dosage against An.Stephensi adults.Conclusions:The screening results suggest that the hexane and methanol extracts of C.celata arc promising in mosquito control.Considering these bioaclivitics.C.celata could the probed further to obtain some novel pesticidal molecules.

  17. Efficacy of larvicidal and pupicidal activity of Catharanthus roseus aqueous and solvent extracts against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Selladurai Subarani; Selvi Sabhanayakam; Chinnaperumal Kamaraj; Gandhi Elango; Mohamed Abdul Kadir

    2013-01-01

    Objective:To investigate the larvicidal and pupicidal activities of aqueous, ethyl acetate and methanol extracts of Catharanthus roseus (C. roseus) against malaria and filariasis vectors. Methods:The larvicidal and pupicidal activities of C. roseus leaf extracts were tested against the fourth instar larvae and pupae of Anopheles stephensi (An. stephensi) and Culex quinquefasciatus (Cx. quinquefasciatus). The mortality was observed after 24 and 48 h post the treatment. The data were subjected to probit analysis to determine the lethal concentrations (LC50 and LC90) at which 50%and 90%of the treated larvae or pupae of the tested species were killed. Results:The larval and pupal mortality were observed after 24 and 48 h of exposure of aqueous, ethyl acetate and methanol extracts of C. roseus; no mortality was observed in the control group. The LC50 values against the fourth-instar larvae of An. stephensi were 68.62 and 72.04 mg/mL for the aqueous extract, 82.47 mg/mL for the ethyl acetate extract, and 78.80 and 86.64 mg/mL for the methanol extract, while the aqueous, ethyl acetate and methanol extracts had LC50 values of 85.21, 76.84 and 94.20 mg/mL against the fourth-instar larvae of Cx. quinquefasciatus. The aqueous, ethyl acetate and methanol extracts had LC50 values of 118.08, 182.47 and 143.80 mg/mL against the pupae of An. stephensi and 146.20, 226.84 and 156.62 mg/mL against the pupae of Cx. quinquefasciatus, respectively. Conclusions: The aqueous and methanol extracts of C. roseus leaves had an excellent potential to control the malarial vector An. stephensi and filariasis vector Cx. quinquefasciatus.

  18. Larvicidal, ovicidal and pupicidal activities ofGliricidia sepium (Jacq.) (Leguminosae) against the malarial vector,Anopheles stephensiListon (Culicidae:Diptera)

    Institute of Scientific and Technical Information of China (English)

    Kaliyamoorthy Krishnappa; Shanmugam Dhanasekaran; Kuppusamy Elumalai

    2012-01-01

    Objective:To investigate the potentiality of mosquitocidal activity ofGliricidia sepium(G. sepium) (Jacq.)(Leguminosae).Methods:Twenty five early third instar larvae ofAnopheles stephensi (An. stephensi) were exposed to various concentrations(50-250 ppm) and the24 hLC50 values of theG. sepium extract was determined by probit analysis.The ovicidal activity was determined againstAn. stephensi to various concentrations ranging from25-100 ppm under laboratory conditions.The eggs hatchability was assessed48 h post treatment.The pupicidal activity was determined againstAn. stephensi to various concentrations ranging from25-100 ppm.Mortality of each pupa was recorded after24 h of exposure to the extract.Results:Results pertaining to the experiment clearly revealed that ethanol extract showed significant larvicidal, ovicidal and pupicidal activity against theAn. stephensi.Larvicidal activityof ethanol extracts ofG. sepium showed maximum mortality in250 ppm concentration(96.0±2.4)%.Furthermore, theLC50 was found to be121.79 and theLC90value was recorded to be231.98 ppm.Ovicidal activity of ethanol extract was assessed by assessing the egg hatchability.Highest concentration of both solvent extracts exhibited100% ovicidal activity.Similarly, pupae exposed to different concentrations of ethanol extract were found dead with58.10% adult emergence when it was treated with25 ppm concentration.Similarly,18.36(n=30;61.20%);21.28(70.93) and27.33(91.10) pupal mortality was recorded from the experimental pupae treated with50,75 and100 ppm concentration of extracts. Three fractions have been tested for their larvicidal activity of which theFraction3 showed the LC50 andLC90 values of23.23 and40.39 ppm.With regard to the ovicidal effect fraction3 showed highest ovicidal activities than the other two fractions.Furthermore, there were no hatchability was recorded above50 ppm(100% egg mortality) in the experimental group.Statistically significant pupicidal activity was recorded from75 ppm

  19. Larvicidal and Biting Deterrent Activity of Essential Oils of Curcuma longa, Ar-turmerone, and Curcuminoids Against Aedes aegypti and Anopheles quadrimaculatus (Culicidae: Diptera).

    Science.gov (United States)

    Ali, Abbas; Wang, Yan-Hong; Khan, Ikhlas A

    2015-09-01

    Essential oils and extract of Curcuma longa, ar-turmerone, and curcuminoids were evaluated for their larvicidal and deterrent activity against mosquitoes. Ar-turmerone and curcuminoids constituted 36.9, 24.9 and 50.6% of rhizome oil, leaf oil, and rhizome extract, respectively. Ar-turmerone was the major compound of the rhizome oil (36.9%) and leaf oil (24.9%). The ethanolic extract had 15.4% ar-turmerone with 6.6% bisdesmethoxycurcumin, 6.1% desmethoxycurcumin, and 22.6% curcumin. In in vitro studies, essential oils of the leaf (biting deterrence index [BDI] = 0.98), rhizome (BDI = 0.98), and rhizome ethanolic extract (BDI = 0.96) at 10 µg/cm(2) showed biting deterrent activity similar to DEET at 25 nmol/cm(2) against Aedes aegypti L. Among the pure compounds, ar-turmerone (BDI = 1.15) showed the biting deterrent activity higher than DEET at 25 nmol/cm(2) whereas the activity of other compounds was lower than DEET. In Anopheles quadrimaculatus Say, only ar-turmerone showed deterrent activity similar to DEET. In dose-response bioassay, ar-turmerone showed significantly higher biting deterrence than DEET at all the dosages. Ar-turmerone, at 15 nmol/cm(2), showed activity similar to DEET at 25 nmol/cm(2) and activity at 5 nmol/cm(2) was similar to DEET at 20 and 15 nmol/cm(2). Leaf essential oil with LC(50) values of 1.8 and 8.9 ppm against larvae of An. quadrimaculatus and Ae. aegypti, respectively, showed highest toxicity followed by rhizome oil and ethanolic extract. Among the pure compounds, ar-turmerone with LC(50) values of 2.8 and 2.5 ppm against larvae of An. quadrimaculatus and Ae. aegypti, respectively, was most toxic followed by bisdesmethoxycurcumin, curcumin, and desmethoxycurcumin.

  20. The abundance and host-seeking behavior of culicine species (Diptera: Culicidae) and Anopheles sinensis in Yongcheng city, people's Republic of China

    Science.gov (United States)

    2011-01-01

    Background The knowledge of mosquito species diversity and the level of anthropophily exhibited by each species in a region are of great importance to the integrated vector control. Culicine species are the primary vectors of Japanese encephalitis (JE) virus and filariasis in China. Anopheles sinensis plays a major role in the maintenance of Plasmodium vivax malaria transmission in China. The goal of this study was to compare the abundance and host-seeking behavior of culicine species and An. sinensis in Yongcheng city, a representative region of P. vivax malaria. Specifically, we wished to determine the relative attractiveness of different animal baits versus human bait to culicine species and An. sinensis. Results Culex tritaeniorhynchus was the most prevalent mosquito species and An. sinensis was the sole potential vector of P. vivax malaria in Yongcheng city. There were significant differences (P < 0.01) in the abundance of both An. sinensis and Cx. tritaeniorhynchus collected in distinct baited traps. The relative attractiveness of animal versus human bait was similar towards both An. sinensis and Cx. tritaeniorhynchus. The ranking derived from the mean number of mosquitoes per bait indicated that pigs, goats and calves frequently attracted more mosquitoes than the other hosts tested (dogs, humans, and chickens). These trends were similar across all capture nights at three distinct villages. The human blood index (HBI) of female An. sinensis was 2.94% when computed with mixed meals while 3.70% computed with only the single meal. 19:00~21:00 was the primary peak of host-seeking female An. sinensis while 4:00~5:00 was the smaller peak at night. There was significant correlation between the density of female An. sinensis and the average relative humidity (P < 0.05) in Wangshanzhuang village. Conclusions Pigs, goats and calves were more attractive to An. sinensis and Cx. tritaeniorhynchus than dogs, humans, and chickens. Female An. sinensis host-seeking activity

  1. The abundance and host-seeking behavior of culicine species (Diptera: Culicidae and Anopheles sinensis in Yongcheng city, people's Republic of China

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    Liu Xiao-Bo

    2011-11-01

    Full Text Available Abstract Background The knowledge of mosquito species diversity and the level of anthropophily exhibited by each species in a region are of great importance to the integrated vector control. Culicine species are the primary vectors of Japanese encephalitis (JE virus and filariasis in China. Anopheles sinensis plays a major role in the maintenance of Plasmodium vivax malaria transmission in China. The goal of this study was to compare the abundance and host-seeking behavior of culicine species and An. sinensis in Yongcheng city, a representative region of P. vivax malaria. Specifically, we wished to determine the relative attractiveness of different animal baits versus human bait to culicine species and An. sinensis. Results Culex tritaeniorhynchus was the most prevalent mosquito species and An. sinensis was the sole potential vector of P. vivax malaria in Yongcheng city. There were significant differences (P An. sinensis and Cx. tritaeniorhynchus collected in distinct baited traps. The relative attractiveness of animal versus human bait was similar towards both An. sinensis and Cx. tritaeniorhynchus. The ranking derived from the mean number of mosquitoes per bait indicated that pigs, goats and calves frequently attracted more mosquitoes than the other hosts tested (dogs, humans, and chickens. These trends were similar across all capture nights at three distinct villages. The human blood index (HBI of female An. sinensis was 2.94% when computed with mixed meals while 3.70% computed with only the single meal. 19:00~21:00 was the primary peak of host-seeking female An. sinensis while 4:00~5:00 was the smaller peak at night. There was significant correlation between the density of female An. sinensis and the average relative humidity (P Conclusions Pigs, goats and calves were more attractive to An. sinensis and Cx. tritaeniorhynchus than dogs, humans, and chickens. Female An. sinensis host-seeking activity mainly occurred from 19:00 to 21:00. Thus

  2. Low-cost and eco-friendly green synthesis of silver nanoparticles using Feronia elephantum (Rutaceae) against Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan; Muthukumaran, Udaiyan

    2014-05-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. The use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of synthesized natural products for vector control have been a priority in this area. In the present study, the larvicidal activity of silver nanoparticles (AgNPs) synthesized using Feronia elephantum plant leaf extract against late third-instar larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus was determined. The range of concentrations of synthesized AgNPs (5, 10, 15, 20, and 25 μg mL(-1)) and aqueous leaf extract (25, 50, 75, 100, and 125 μg mL(-1)) were tested against the larvae of A. stephensi, A. aegypti, and C. quinquefasciatus. Larvae were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of F. elephantum for all three important vector mosquitoes. The synthesized AgNPs from F. elephantum were highly toxic than crude leaf aqueous extract to three important vector mosquito species. The results were recorded from UV-visible spectroscopy, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and energy-dispersive X-ray spectroscopy analysis (EDX). Synthesized AgNPs against the vector mosquitoes A. stephensi, A. aegypti, and C. quinquefasciatus had the following LC50 and LC90 values: A. stephensi had LC50 and LC90 values of 11.56 and 20.56 μg mL(-1); A. aegypti had LC50 and LC90 values of 13.13 and 23.12 μg mL(-1); and C. quinquefasciatus had LC50 and LC90 values of 14.19 and 24.30 μg mL(-1). No mortality was observed in the control. These results suggest that the green synthesis of silver nanoparticles using F. elephantum has the potential to be used as an ideal eco-friendly approach for the control of A. stephensi, A. aegypti, and C

  3. Mosquito larvicidal potential of silver nanoparticles synthesized using Chomelia asiatica (Rubiaceae) against Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-03-01

    Mosquitoes transmit serious human diseases, causing millions of deaths every year. Mosquito control is to enhance the health and quality of life of county residents and visitors through the reduction of mosquito populations. Mosquito control is a serious concern in developing countries like India due to the lack of general awareness, development of resistance, and socioeconomic reasons. Today, nanotechnology is a promising research domain which has a wide ranging application in vector control programs. These are nontoxic, easily available at affordable prices, biodegradable, and show broad-spectrum target-specific activities against different species of vector mosquitoes. In the present study, larvicidal activity of aqueous leaf extract and silver nanoparticles (AgNPs) synthesized using C. asiatica plant leaves against late third instar larvae of Anopheles stephensi, Aedes aegypti, and Cx. quinquefasciatus. The range of varying concentrations of synthesized AgNPs (8, 16, 24, 32, and 40 μg/mL) and aqueous leaf extract (40, 80, 120, 160, and 200 μg/mL) were tested against the larvae of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus. The synthesized AgNPs from C. asiatica were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy analysis (EDX). Considerable mortality was evident after the treatment of C. asiatica for all three important vector mosquitoes. The LC50 and LC90 values of C. asiatica aqueous leaf extract appeared to be effective against An. stephensi (LC50, 90.17 μg/mL; LC90, 165.18 μg/mL) followed by Ae. aegypti (LC50, 96.59 μg/mL; LC90, 173.83 μg/mL) and Cx. quinquefasciatus (LC50, 103.08 μg/mL; LC90, 183.16 μg/mL). Synthesized AgNPs against the vector mosquitoes of An. stephensi, Ae. aegypti, and Cx. quinquefasciatus had the following LC50 and LC90

  4. Green synthesis of silver nanoparticles using Sida acuta (Malvaceae) leaf extract against Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2013-12-01

    Mosquitoes act as a vector for most of the life-threatening diseases like malaria, yellow fever, dengue fever, chikungunya fever, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management, emphasis was given on the application of alternative strategies in mosquito control. The continuous application of synthetic insecticides causes development of resistance in vector species, biological magnification of toxic substances through the food chain, and adverse effects on environmental quality and nontarget organisms including human health. Application of active toxic agents from plant extracts as an alternative mosquito control strategy was available from ancient times. These are nontoxic, easily available at affordable prices, biodegradable, and show broad-spectrum target-specific activities against different species of vector mosquitoes. In the present study, the larvicidal activity of silver nanoparticles (AgNPs) synthesized using Sida acuta plant leaf extract against late third instar larvae of Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti was determined. Range of concentrations of synthesized AgNPs (10, 20, 30, 40, and 50 μg/mL) and aqueous leaf extract (50, 100, 150, 200, and 250 μg/mL) were tested against the larvae of C. quinquefasciatus, A. stephensi and A. aegypti. The synthesized AgNPs from S. acuta leaf were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis. Larvae were exposed to varying concentrations of aqueous crude extract and synthesized AgNPs for 24 h. Considerable mortality was evident after the treatment of S. acuta for all three important vector mosquitoes. The LC50 and LC90 values of S. acuta aqueous leaf extract appeared to be most effective

  5. Studies on the impact of biosynthesized silver nanoparticles (AgNPs) in relation to malaria and filariasis vector control against Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Subarani, Selladurai; Sabhanayakam, Selvi; Kamaraj, Chinnaperumal

    2013-02-01

    Biosynthesized nanoparticles have been achieved using environmentally acceptable plant extract and eco-friendly reducing and capping agents. The present study was based on assessments of the larvicidal activities to determine the efficacies of synthesized silver nanoparticles (AgNPs) using aqueous leaf extract of Vinca rosea (L.) (Apocynaceae) against the larvae of malaria vector Anopheles stephensi Liston and filariasis vector Culex quinquefasciatus Say (Diptera: Culicidae). Larvae were exposed to varying concentrations of aqueous extract of V. rosea and synthesized AgNPs for 24, 48, and 72 h. AgNPs were rapidly synthesized using the leaf extract of V. rosea, and the formation of nanoparticles was observed within 15 min. The results recorded from UV-Vis spectrum, Fourier transform infrared (FTIR), X-ray diffraction (XRD), scanning electron microscopy (SEM), and transmission electron microscopy (TEM) support the biosynthesis and characterization of AgNPs. The formation of the AgNPs synthesized from the XRD spectrum compared with the Bragg reflections at 2θ = 29.36, 38.26, 44.51, 63.54, and 77.13° which can be indexed to the (121), (111), (200), (220), and (311) orientations, respectively, confirmed the presence of AgNPs. The FTIR spectra of AgNPs exhibited prominent peaks at the spectra showed sharp and strong absorption band at 3,406.71 to 3,431.90 cm(-1) double in case of NH(2) group of a primary amine (N-H stretch). The presence of the sharp peak at 2,926.54 to 2,925.80 cm(-1) very broad often looks like distorted baseline (O-H carboxylic acids). The band 1,633.26 to 1,625.81 cm(-1) was assigned to C = C alkenes, aromatic ring stretching vibration, respectively. SEM analysis of the synthesized AgNPs clearly showed the clustered and irregular shapes, mostly aggregated and having the size of 120 nm. TEM reveals spherical shape of synthesized AgNPs. Particle size analysis revealed that the size of particles ranges from 25 to 47 nm with average size of 34.61 nm

  6. Determinação das fontes alimentares de Anopheles aquasalis (Diptera: Culicidae no Estado do Rio de Janeiro, Brasil, pelo teste de precipitina Blood-meal sources of Anopheles aquasalis (Diptera: Culicidae in a South-eastern State of Brazil

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    Carmen Flores-Mendoza

    1996-04-01

    Full Text Available Anopheles aquasalis é um mosquito ora encarado como antropofílico, ora como zoofílico ou eclético. Realizou-se estudo em Guapimirim, Estado do Rio de Janeiro, de maio a novembro de 1992, com o intuito de se verificar a fonte alimentar preferida desse anofelino através de teste imunológico de precipitina. De 1.366 fêmeas capturadas em abrigos naturais, 725 estavam ingurgitadas. O conteúdo digestivo de apenas 473 delas reagiu no teste de precipitina, sendo que em 75,3% dos casos foi identificada apenas uma fonte alimentar. Mais da metade dessas fêmeas havia se alimentado em boi (52,2%, enquanto poucas tinham sugado homem (1,1%. Por outro lado, 24,7% dos espécimes haviam se alimentado em mais de uma fonte sangüínea, principalmente boi e cavalo. Conclui-se que An. aquasalis é zoófilo nessa região do País, utilizando grande variedade de hospedeiros, porém preferindo se alimentar em animais de grande porte, especialmente o boi e cavalo.Anopheles aquasalis has shown local variations in blood-host preference in Brazil: it seems to be anthropophilic in the northeast and zoophilic or opportunistic in the Amazon and other regions. A study was carried out in Guapimirim county, State of Rio de Janeiro, from May to November 1992, for the purpose of identifying the blood meal source of this anopheline by capillary tube precipitin test. A total of 1,366 females were captured at natural resting-places, 725 of which were blood-fed. The gut content of 473 blood fed females reacted to the antisera used (human, cow, horse, pig, dog and chicken. The majority of the females ¾ 356 (75.3% ¾ had blood from only one source. A substantial bovine preference was observed ¾ 52.2% had fed on cows, 29.8% on horses, 10.7% on pigs, 4.5% on chickens and 1.7% on dogs, but only few had fed on man (1.1% and none on rats. On the other hand, 24.7% of the females had fed on more than one host, mainly on cows and horses. It was assumed that An. aquasalis is zoophilic

  7. Distribuição das espécies do gênero Anopheles (Diptera, Culicidae no Estado do Maranhão, Brasil Distribution of species from genus Anopheles (Diptera, Culicidae in the State of Maranhão, Brazil

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    José M. Macário Rebêlo

    2007-12-01

    Full Text Available Estudou-se a distribuição e diversidade de espécies de Anopheles em 123 municípios do Estado do Maranhão, Brasil. O método básico foi a captura de fêmeas dentro e nos arredores das habitações humanas, em intervalos compreendidos entre 18h e 6h, no período de janeiro de 1992 a dezembro de 2001. Foram capturados 84.467 exemplares distribuídos em 24 espécies, com o predomínio de A. triannulatus sensu lato (20.788, A. darlingi (19.083, A. nuneztovari (16.884, A. albitarsis s.l. (14.352, A. aquasalis (8.202 e A. evansae (2.885. As outras 18 espécies juntas representaram apenas 2,7%. As espécies encontradas no maior número de municípios foram: A. albitarsis s.l. (109 municípios, A. triannulatus s.l. (106, A. nuneztovari (93, A. darlingi (87 e A. evansae (64. A riqueza e a ampla distribuição das espécies de anofelinos no Maranhão concordam com a posição geográfica do estado, entre as macrorregiões que caracterizam o Brasil, resultando em uma fauna mista, com elementos representativos dessas regiões.We studied the distribution and diversity of Anopheles species in 123 counties (municipalities in the State of Maranhão, Brazil. The basic method consisted of capturing female specimens inside and around human dwellings between 6 PM and 6 AM from January 1992 to December 2001. A total of 84,467 specimens belonging to 24 species were captured, with a predominance of A. triannulatus sensu lato (20,788, A. darlingi (19,083, A. nuneztovari (16,884, A. albitarsis s.l. (14,352, A. aquasalis (8.202, and A. evansae (2,885. The other 18 species together accounted for only 2.7% of the total. The species found in the most counties were A. albitarsis s.l. (109 counties, A. triannulatus s.l. (106, A. nuneztovari (93, A. darlingi (87, and A. evansae (64. The richness and wide distribution of anopheline species in Maranhão agree with the State's geographic position among Brazil's macro-regions, resulting in a mixed fauna with representative

  8. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 1- Parity of blood seeking Anopheles (Kerteszia in South-Eastern Brazil Estudos sobre mosquitos (Diptera: Culicidae e ambiente antrópico: 1- Paridade de Anopheles (Kerteszia em atividade hematófaga, na região sudeste do Brasil

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    Oswaldo Paulo Forattini

    1993-02-01

    Full Text Available Populations of Anopheles (Kerteszia were sampled fortnightly over a one-year period (August 1991 to July 1992 at Ribeira Valley, S. Paulo State, Brazil. Indoor and outdoor collections were made on human bait at evening crepuscular period. The Polovodova technique for age grading was applied to 3,501 females of Anopheles cruzii and to 416 females of An. bellator. That sample represented 34.4% of the total number of mosquitoes collected. The most abundant species found was An. cruzii. However, An. bellator showed an endophagy that was almost three times greater than that of An. cruzii. The overall parous rate was 25.4% and uniparity was practically dominant one. A proportion of 26.9% of An. cruzii and 12.0% of An. bellator were found to be uniparous. Only three outdoor females of the former species (0.1% showed biparity. Parity of An. cruzii was higher in females caught outdoors than in those caught indoors. Nevertheless, 497 nulliparous females examined (417 cruzii and 80 bellator had ovaries that had advanced to Christophers and Mer stages III to V. These results imply that these females had already practised hematophagy. Relating these results to those from the parous females, a high statistical significance was found, leading to the conclusion that gonothophic discordance is a common pattern among these anophelines. Further, these results obtained with human bait catches strongly suggest that nearly 38.0% of these host-seeking females had already taken at least one previous blood-meal. So it is possible that enough time could thus be available for the plasmodian development in the vectors.Relata-se os resultados obtidos em coletas regulares de Anopheles cruzii e An. bellator, mediante o emprego de isca humana e por ocasião do crepúsculo vespertino. Objetivou-se, precipuamente, conhecer a paridade de populações dessas espécies, quando em plena tentativa hematófaga, tanto no ambiente intra como peridomiciliar. As coletas foram levadas a

  9. Short report : Development of a molecular assay to detect predation on Anopheles gambiae complex larval stages

    OpenAIRE

    Schielke, E.; Costantini, Carlo; Carchini, G.; Sagnon, N.; J. Powell; Caccone, A

    2007-01-01

    We developed a molecular assay to detect predation on Anopheles gambiae sensu lato (s.l.) mosquitoes. This intergenic spacer ribosomal DNA polymerase chain reaction assay and restriction enzyme analysis uses An. gambiae-specific primers to detect mosquito DNA in the DNA extracts from whole invertebrate predators, which enables identification of species (An. gambiae s.s. versus An. arabiensis) and molecular forms (M versus S in An. gambiae s.s.). We show that An. gambiae s.l. DNA can be detect...

  10. Assessment of Anopheles salivary antigens as individual exposure biomarkers to species-specific malaria vector bites

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    Ali Zakia M I

    2012-12-01

    Full Text Available Abstract Background Malaria transmission occurs during the blood feeding of infected anopheline mosquitoes concomitant with a saliva injection into the vertebrate host. In sub-Saharan Africa, most malaria transmission is due to Anopheles funestus s.s and to Anopheles gambiae s.l. (mainly Anopheles gambiae s.s. and Anopheles arabiensis. Several studies have demonstrated that the immune response against salivary antigens could be used to evaluate individual exposure to mosquito bites. The aim of this study was to assess the use of secreted salivary proteins as specific biomarkers of exposure to An. gambiae and/or An. funestus bites. Methods For this purpose, salivary gland proteins 6 (SG6 and 5′nucleotidases (5′nuc from An. gambiae (gSG6 and g-5′nuc and An. funestus (fSG6 and f-5′nuc were selected and produced in recombinant form. The specificity of the IgG response against these salivary proteins was tested using an ELISA with sera from individuals living in three Senegalese villages (NDiop, n = 50; Dielmo, n = 38; and Diama, n = 46 that had been exposed to distinct densities and proportions of the Anopheles species. Individuals who had not been exposed to these tropical mosquitoes were used as controls (Marseille, n = 45. Results The IgG responses against SG6 recombinant proteins from these two Anopheles species and against g-5′nucleotidase from An. gambiae, were significantly higher in Senegalese individuals compared with controls who were not exposed to specific Anopheles species. Conversely, an association was observed between the level of An. funestus exposure and the serological immune response levels against the f-5′nucleotidase protein. Conclusion This study revealed an Anopheles salivary antigenic protein that could be considered to be a promising antigenic marker to distinguish malaria vector exposure at the species level. The epidemiological interest of such species-specific antigenic markers is discussed.

  11. Resistance Status of the Malaria Vector Mosquitoes, Anopheles stephensi and Anopheles subpictus Towards Adulticides and Larvicides in Arid and Semi-Arid Areas of India

    OpenAIRE

    Tikar, S. N.; M J Mendki; Sharma, A K; D. Sukumaran; Veer, Vijay; Prakash, Shri; Parashar, B. D.

    2011-01-01

    Susceptibility studies of malaria vectors Anopheles stephensi Liston (Diptera: Culicidae) and An. subpictus Grassi collected during 2004–2007 from various locations of Arid and Semi-Arid Zone of India were conducted by adulticide bioassay of DDT, malathion, deltamethrin and larvicide bioassay of fenthion, temephos, chlorpyriphos and malathion using diagnostic doses. Both species from all locations exhibited variable resistance to DDT and malathion from majority of location. Adults of both the...

  12. Biología de Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae en la Costa Pacifica de Colombia: IV - Estructura etárea y transmisión de malaria Biologia do Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae na Costa do Pacífico Colombiano: IV - Estrutura etária e transmissão da malária Biology of Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae on the Pacific Coast of Colombia: IV - Age structure and malaria transmission

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    César Murillo B.

    1989-10-01

    Full Text Available Con el fin de determinar la dinamica de transmisión de malaria en el poblado de Charambirá (Chocó, Colombia, se estudió la estructura etárea de Anopheles neivai (reconocido vector en la Costa Pacífica con base en su estado gonadotrófico. Se recolectaron mosquitos intradomiciliarmente durante el crepúsculo vespertino con cebos humanos y aspiradores bucales. Los mosquitos recolectados se mantuvieron en cajas cilíndricas de cartón con papel humedecido y dispensadores alimenticios hasta su disección al día siguiente. De los 200 mosquitos disecados entre septiembre y octubre de 1986,68 (34% presentaban huellas de menos de tres oviposturas y los restantes (66% habían efectuado al menos tres oviposturas. La diferencia entre el primer grupo considerado como mosquitos "no infectivos" y el segundo considerado como los "potencialmente infectivos" fue altamente significativa (X² = 10,68; P = 0,001. El 1,5% de A. neivai estudiados presentaban huellas correspondientes a 10 oviposturas mostrando una marcada longevidad y múltiples alimentaciones sanguíneas. Los resultados sugieren que existe un alto riesgo de contraer malaria en Charambirá durante el crepúsculo vespertino.Com o intuito de determinar a dinâmica de transmissão da malária no povoado de Charambirá (Chocó, Colômbia, foi estudada a estrutura etária do mosquito Anopheles neivai (reconhecido vetor da Costa Pacífica com base em seu estado gonadotrófico. As coletas foram realizadas intradomiciliarmente no crepúsculo vespertino com isca humana e auxílio de tubos de sucção manual. Os mosquitos coletados foram mantidos em caixas cilíndricas de papelão, contendo papel umidecido e alimento. Dos 200 mosquitos dissecados entre setembro e outubro de 1986, 68 (34% apresentaram vestígios de menos de três oviposturas (oviposições e os demais (66% apresentavam, pelo menos, três ovipoturas. A diferença entre o primeiro grupo considerado como mosquitos "não infectantes" e o

  13. Taxonomy Icon Data: Anopheles stephensi [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available Anopheles stephensi Anopheles stephensi Arthropoda Anopheles_stephensi_L.png Anopheles_stephen...si_NL.png Anopheles_stephensi_S.png Anopheles_stephensi_NS.png http://biosciencedbc.jp/taxonomy_i...con/icon.cgi?i=Anopheles+stephensi&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&...t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&t=S htt...p://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Anopheles+stephensi&t=NS http://togodb.biosciencedbc.jp/togodb/view/taxonomy_icon_comment_en?species_id=149 ...

  14. Energy-state dependent responses of Anopheles gambiae to an unobtainable host

    OpenAIRE

    Zappia, Simon Pierre William

    2011-01-01

    Understanding how blood-seeking behavior changes with different energy levels in the malaria mosquito Anopheles gambiae (Diptera: Culicidae), when confronted with an unobtainable blood-host, is of interest for vector control strategies. I used a straight-tube olfactometer to mimic a domicile containing (i) a simulated blood-host (human foot smell) protected by either a plain bednet or a DEET impregnated net and (ii) a sugar source (honey scent) some distance away. I manipulated the mosquito’s...

  15. Mosquito repellent action of Blumea lacera (Asteraceae) against Anopheles stephensi and Culex quinquefasciatus.

    OpenAIRE

    Singh, S.P.; MITTAL, P.K.

    2014-01-01

    Petroleum ether extract of Blumea lacera was screened under laboratory conditions for repellent activity against mosquito vector Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae). The repellent activity of Blumea lacera extract was tested against mosquitoes in comparison with the DEET, which was used as a positive control. Results obtained from the laboratory experiment showed that the extract was effective against mosquito vectors even at a low dose. A direct rel...

  16. Biologia de Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae en la costa Pacífica de Colombia: I. Fluctuación de la población larval y características de sus criaderos Biologia de Anopheles (Kerteszia neivai H., D. & K,, 1913 (Diptera: Culicidae na costa do Pacífico Colombiano: I. Flutuação da população larval e características dos seus berçários (criadouros Biology of Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae on the Pacific coast of Colombia: I. Fluctuation of larval population and characteristics of the breeding places

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    César Murillo B.

    1988-04-01

    Full Text Available En Charambirá, localidad del município de Istmina (Chocó en la costa Pacífica de Colombia, donde existe un problema de malaria endémica, se estudió la fluctuación de la población larval y las características de los criaderos de Anopheles (Kerteszia neivai, especie considerada como posible vectora de malaria en esa región del país. La vegetación circundante fue dividida en tres estratos de acuerdo al grado de cobertura foliar. Se demarcaron cuadrantes de 100 m² en cada estrato para el muestreo de plantas epífitas de la família Bromeliaceae, en las cuales se acumula agua que sirve como criadero para esta especie de anofelino. Se tomaron datos de temperatura, pH y volumen del agua contenida en cada bromelia. El mayor número de larvas se detectó en el estrato 1 (manglar a una altitud inferior a 4 m, pero no se encontró evidencia significativa de estratificación vertical de la población larval de A. neivai hasta los 8 m. Se evidenció una correlación lineal positiva entre el número de larvas y el volumen de agua contenida en cada bromelia; por otra parte se observó también una correlación directa entre la precipitación mensual acumulada y la fluctuación poblacional de esta especie. Los índices larvales mas altos se observaron entre los meses de marzo a abril y de julio a agosto. La mortalidad larval fue alta en el primer estadío (43,5% y solo un 23,7% sobrevivió hasta el cuarto.Em Charambirá, localidade do Município de Istmina (Chocó, na costa do Pacífico Colombiano, localidade endêmica de malária, estudou-se a flutuação da população larval e as características dos locais de criação do Anopheles (Kerteszia neivai, espécie considerada como possível vector da malária naquela região do país. A vegetação circundante foi dividida em três estratos segundo seu grau de cobertura foliar. Demarcaram-se quadrantes de 100 m² para a amostragem de plantas epífitas da família Bromeliaceae, nas quais se

  17. Biologia de Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae en la costa Pacífica de Colombia: II. Fluctuación de la población adulta Biologia do Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae na costa do Pacífico Colombiano: II. Flutuação da população adulta Biology of Anopheles (Kerteszia neivai H., D. & K., 1913 (Diptera: Culicidae on the Pacific Coast of Colombia: II. Adult population fluctuation

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    Rodrigo Astaiza V.

    1988-04-01

    Full Text Available En la localidad de Charambirá, situada en el município de Istmina (Chocó en la costa Pacífica de Colombia, se presenta un problema de malaria endémica asociada con grandes poblaciones de mosquitos Anopheles del subgénero Kerteszia (A. neivai. Estos se crían en las colecciones de agua formadas por plantas epífitas de la família Bromeliaceae, que son muy abundantes en los árboles de mangle. En esa localidad se estudiaron: fluctuación poblacional y algunos aspectos ecológicos y etológicos de los adultos de esa especie de mosquito, con el objetivo de determinar su papel en la transmisión de malaria. Todos los mosquitos fueron colectados por cebos humanos. Los picos máximos de actividad ocurrieron en las horas crepusculares de la mañana y de la tarde (5:30 a 6:30 y 18:00 a 19:00 horas. En el período nocturno la actividad intradomiciliar fue baja y no hubo ninguna durante el día. El estado gonadotrófico de las hembras colectadas durante nos picos de actividad, mostró la existencia de dos poblaciones de mosquitos: una, en su mayoría individuos jóvenes que buscan su alimento en las horas de la tarde y la otra compuesta por individuos mas longevos, que buscan su alimento en la mañana. El estudio de la variación estacional mostró que las poblaciones son bajas en los meses de poca precipitación, pero a medida que aumenta el índice pluviométrico, aumenta el número de mosquitos. Se discute la relación que existe entre la presencia de los mosquitos y la prevalencia de malaria humana; se sugiere que A. neivai puede ser el responsable de la transmisión de malaria en la zona estudiada.Na localidade de Charambirá, situada no Municipio de Istmina (Chocó, na costa do Pacífico Colombiano, ocorre um tipo de malária endêmica associada com grandes populações de Anopheles do subgênero Kerteszia (A. neivai. Estes criam-se em coleções de água formadas por plantas epífitas pertencentes à família Bromeliaceae, as quais são muito

  18. Prevalence of anopheles (Diptera: Culicidae) during sunset in areas of the Itaipu Hydroelectric Power Plant in Guaira County, State of Parana, Brazil; Prevalencia de anofelinos (Diptera: Culicidae) no crepusculo vespertino em areas da Usina Hidreletrica de Itaipu, no Municipio de Guaira, Estado do Parana, Brasil

    Energy Technology Data Exchange (ETDEWEB)

    Guimaraes, Anthony Erico; Mello, Rubens Pinto de; Lopes, Catarina Macedo; Alencar, Jeronimo; Gentile, Carla [Fundacao Inst. Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Dept. de Entomologia. Lab. de Diptera

    1997-11-01

    Systematic collections of anophelines were conducted from November 1995 to August 1995 from 18:00 to 20:00 hr using Shannon traps and human-bait along the lake margin which forms the Itaipu Hydroelectric Reservoir, State of Parana, Brazil. Species prevalence was studied at 15 min intervals. Anopheles albitarsis sensu latu and An. galvaoi, were the most frequently collected mosquitoes. All Anopheles species populations peaked between 18:45 and 19:30 hr. The observations illustrate the existence of haematophagic activity cycle during the early evening hours: exogenous stimulus (the beginning of sunset) Shannon trap (light attraction) human bait (haematophagy) rest and digestion exogenous stimulus Shannon trap or surrounding vegetation. The greater abundance of An. albitarsis collected in human-bait and Shannon trap suggests it may be a potential malaria vector in the region. (author) 20 refs.

  19. New species of Paracalanidae along the west coast of India: Paracalanus arabiensis

    Digital Repository Service at National Institute of Oceanography (India)

    Kesarkar, K.S.; Anil, A.C.

    and 12 respectively. Antenna (Figure 3B): biramous; coxa and basis clearly separate, bearing 1 and 2 setae respectively. Exopod 7-segmented, slightly longer than endopod, segment 1 with 2 setae, segments 2 - 6 with 1 seta each, segment 7 bearing..., dorsal view. Fig. 3. Paracalanus arabiensis sp. nov., female (holotype). (A) Antennule; (B) antenna; (C) mandible; (D) maxillule; (E) maxilla; (F) maxilliped. Fig. 4. Paracalanus arabiensis sp. nov., female. (holotype). (A) Leg 1; (B) leg 2; (C) leg 3...

  20. Identification of candidate volatiles that affect the behavioural response of the malaria mosquito Anopheles gambiae sensu stricto to an active kairomone blend: laboratory and semi-field assays

    NARCIS (Netherlands)

    Smallegange, R.C.; Bukovinszkine Kiss, G.; Otieno, B.; Mbadi, P.A.; Takken, W.; Mukabana, W.R.; Loon, van J.J.A.

    2012-01-01

    Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is the most important vector of human malaria in sub-Saharan Africa, affecting the lives of millions of people. Existing tools such as insecticide-treated nets and indoor-residual sprays are not only effective, but also have limitations as a

  1. Structure of host-odour plumes influences catch of Anopheles gambiae s.s. and Aedes aegypti in a dual-choice olfactometer

    NARCIS (Netherlands)

    Dekker, T.; Takken, W.; Cardé, R.T.

    2001-01-01

    The effects of structure, concentration and composition of host-odour plumes on catch of female Anopheles gambiae Giles sensu stricto and Aedes aegypti (L.) (Diptera: Culicidae) were investigated in a dual-choice olfactometer. We demonstrate that the fine-scale structure of host-odour plumes modulat

  2. "Use of Random Amplified Polymorphic DNA Polymerase Chain Reaction (RAPD-PCR and ITS2 PCR assays for differentiation of populations and putative sibling species of Anopheles fluviatilis (Diptera: Culicidae in Iran"

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    SR Naddaf Dezfouli

    2002-09-01

    Full Text Available Anopheles fluviatilis complex is known to be a vector of malaria in Iran. Since mosquitoes of this species cover a wide geographical range in Iran, they might have evolved into different separated populations. Random amplified polymorphic DNA polymerase chain reaction (RAPD-PCR assay was used to differentiate geographic populations of this species. DNA was extracted from individual mosquitoes from 8 localities in 4 south and southeast provinces and amplified in PCR reactions using 18 single primers of arbitrary nucleotide sequence. Results of RAPD-PCR showed that Kazeroun populations could simply be differentiated from other populations using a diagnostic fragment amplified with primer UBC-306. But other populations could not be differentiated either visually or by means of statistical analysis. Moreover ITS2 fragments of some selected specimens were amplified using a pair of universal primer and sequenced as a key standard for detection of putative sibling species. Sequence analysis of the ITS2 fragments revealed a very high (100% homology among the populations. These findings are crucial in epidemiological studies concerning relatedness of geographic populations and vector movement in the region. Results of RAPD-PCR and ITS2 analysis suggest that this taxon in Iran comprises of only one species with a low genetic variation among geographic populations.

  3. Frequent blood-feeding and restrictive sugar-feeding behavior enhance the malaria vector potential of Anopheles gambiae s.l. and An. funestus (Diptera:Culicidae) in western Kenya.

    Science.gov (United States)

    Beier, J C

    1996-07-01

    Natural blood-feeding and sugar-feeding behaviors were investigated for populations of Anopheles gambiae s.l. and An. funestus Giles at 2 sites in western Kenya. During peak levels of malaria parasite transmission, > 85% of 1,569 indoor-resting females contained fresh blood meals. Findings that up to 55.4% of blood-fed resting females and 72.0% of host-seeking females had either stage IV or V oocytes provided strong evidence that females were refeeding before oviposition. Such gonotrophic discordance was common throughout the year for both An. gambiae s.l. and An. funestus. Determinations of gonotrophic cycles for freshly blood-fed mosquitoes collected inside houses indicated that only 60.0% of 1,287 An. gambiae s.l. and 60.0% of 974 An. funestus oviposited eggs after a single blood meal. The timing of oviposition was irregular as indicated by relatively high coefficients of variation for An. gambiae s.l. (44.0%) and An. funestus (35.9%). Associated with frequent blood feeding was a surprisingly low rate of sugar feeding; only 6.3% of 1,183 indoor-resting and only 14.4% of 236 host-seeking anophelines were positive for fructose. Natural patterns of frequent blood feeding, year-round gonotrophic discordance, irregular oviposition cycles, and limited sugar feeding illustrate that anopheline mosquitoes have complex behavioral and physiologic means for adapting to their environment. In western Kenya, for example, adaptations for frequent blood feeding by An. gambiae s.l. and An. funestus potentiates their ability to transmit malaria parasites, well beyond that predicted by standard measures of vectorial capacity. PMID:8699456

  4. Development of a molecular assay to detect predation on Anopheles gambiae complex larval stages.

    Science.gov (United States)

    Schielke, Erika; Costantini, Carlo; Carchini, Gianmaria; Sagnon, N'falé; Powell, Jeffrey; Caccone, Adalgisa

    2007-09-01

    We developed a molecular assay to detect predation on Anopheles gambiae sensu lato (s.l.) mosquitoes. This intergenic spacer ribosomal DNA polymerase chain reaction assay and restriction enzyme analysis uses An. gambiae-specific primers to detect mosquito DNA in the DNA extracts from whole invertebrate predators, which enables identification of species (An. gambiae s.s. versus An. arabiensis) and molecular forms (M versus S in An. gambiae s.s.). We show that An. gambiae s.l. DNA can be detected after ingestion by members of the families Lestidae (order Odonata) after four hours, Libellulidae (order Odonata) after six hours, and Notonectidae (order Hemiptera) after 24 hours. This method is an improvement over previously published methods because of ease of execution and increased time of detection after ingestion. PMID:17827361

  5. Nota sobre culicídeos (Diptera: Culicidae da bacia do rio Purus, Acre, Amazônia (Brasil

    Directory of Open Access Journals (Sweden)

    Delsio Natal

    1992-04-01

    Full Text Available Foram feitas coletas de mosquito (Diptera: Culicidae na área do projeto de Colonização Pedro Peixoto, no Estado do Acre, Brasil. Obteve-se um total de 4.588 exemplares pertencentes a 53 espécies ou grupos. Salienta-se a ocorrência de Anopheles (Nyssorhynchus oswaldoi.

  6. α-Humulene and β-elemene from Syzygium zeylanicum (Myrtaceae) essential oil: highly effective and eco-friendly larvicides against Anopheles subpictus, Aedes albopictus, and Culex tritaeniorhynchus (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Benelli, Giovanni

    2016-07-01

    Mosquitoes transmit serious pathogens and parasites to humans and animals, including malaria, dengue, Japanese encephalitis and filariasis. The extensive use of chemical pesticides leads to the development of resistance in mosquito vector populations and serious non-target effects on human health and the environment. Myrtaceae plants can be a useful reservoir of natural products effective against Culicidae young instars. In this research, we evaluated the mosquitocidal potential of the essential oil (EO) from Syzygium zeylanicum leaves against larvae of three mosquitoes of medical and veterinary importance, the malaria vector Anopheles subpictus, the dengue vector Aedes albopictus, and the Japanese encephalitis vector Culex tritaeniorhynchus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the S. zeylanicum EO contained at least 18 compounds. The major chemical components were α-humulene (37.8.5 %) and β-elemene (10.7 %). The EO had a significant toxic effect against early third-stage larvae of An. subpictus, Ae. albopictus, and Cx. tritaeniorhynchus, with LC50 values of 83.11, 90.45, and 97.96 μg/ml, respectively. The two major constituents extracted from the S. zeylanicum EO were tested individually for acute toxicity against larvae of the three mosquito vectors. α-Humulene and β-elemene appeared highly effective against An. subpictus (LC50 = 6.19 and 10.26 μg/ml, respectively), followed by Ae. albopictus (LC50 = 6.86 and 11.15 μg/ml) and Cx. tritaeniorhynchus (LC50 = 7.39 and 12.05 μg/ml). Furthermore, the EO and its major components was safe towards the non-target fish Gambusia affinis; LC50 values were 20374.26, 1024.95, and 2073.18 μg/ml, respectively for EO, α-humulene and β-elemene. Overall, this study highlighted that the acute toxicity of S. zeylanicum EO towards mosquito larvae was mainly due to the presence of α-humulene and β-elemene. Furthermore, we pointed

  7. The nicotinic acetylcholine receptor gene family of the malaria mosquito, Anopheles gambiae.

    Science.gov (United States)

    Jones, Andrew K; Grauso, Marta; Sattelle, David B

    2005-02-01

    Nicotinic acetylcholine receptors (nAChRs) mediate fast cholinergic synaptic transmission in the insect nervous system and are targets of widely selling insecticides. We have identified the nAChR gene family from the genome of the malaria mosquito vector, Anopheles gambiae, to be the second complete insect nAChR gene family described following that of Drosophila melanogaster. Like Drosophila, Anopheles possesses 10 nAChR subunits with orthologous relationships evident between the two insects. Interestingly, the Anopheles orthologues of Dbeta2 and Dbeta3 possess the vicinal cysteines that define alpha subunits. As with Dalpha4 and Dalpha6, the Anopheles orthologues are alternatively spliced at equivalent exons. Reverse transcription-polymerase chain reaction analysis shows that RNA A-to-I editing sites conserved between Dalpha6 of Drosophila and alpha7-2 of the tobacco budworm, Heliothis virescens, are not shared with the equivalent nAChR subunit of Anopheles. Indeed, RNA-editing sites identified in functionally significant regions of Dbeta1, Dalpha5, and Dalpha6 are not conserved in the mosquito orthologues, indicating considerable divergence of RNA molecules targeted for editing within the insect order Diptera. These findings shed further light on the diversity of nAChR subunits and may present a useful basis for the development of improved malaria control agents by enhancing our understanding of a validated mosquito insecticide target.

  8. Physiology and development of the M and S molecular forms of Anopheles gambiae in Burkina Faso (West Africa)

    OpenAIRE

    Mouline, Karine; Mamai, W.; Agnew, P.; Tchonfienet, M.; Brengues, Cécile; Dabiré, R.; Robert, Vincent; Simard, Frédéric

    2012-01-01

    In West Africa, M and S molecular forms of Anopheles gambiae sensu stricto (Diptera: Culicidae) Giles, frequently occur together, although with different population bionomics. The S form typically breeds in rain-dependant water collections and is present during the rainy season only whereas the M form can thrive all year long in areas with permanent breeding opportunities. In the present study, we explored physiological and developmental trade-offs at play in laboratory colonies and field pop...

  9. Feeding and indoor resting behaviour of the mosquito Anopheles longipalpis in an area of hyperendemic malaria transmission in southern Zambia

    OpenAIRE

    Kent, R.J.; Coetzee, M.; Mharakurwa, S.; Norris, D. E.

    2006-01-01

    Anopheles longipalpis (Theobald) (Diptera: Culicidae) is a predominantly zoophilic mosquito that has not been implicated in malaria transmission. However, this species was collected indoors with An. funestus s.l. in southern Zambia, where transmission of Plasmodium falciparum is hyperendemic, and we initially misidentified it morphologically and molecularly as An. funestus s.l. The indoor resting density and blood-feeding behaviour of An. longipalpis were investigated during the 2004 – 05 and...

  10. Insecticide resistance in Anopheles gambiae from south-western Chad, Central Africa

    Directory of Open Access Journals (Sweden)

    Etang Josiane

    2008-09-01

    Full Text Available Abstract Background Indoor residual spraying and insecticide-treated nets (ITN are essential components of malaria vector control in Africa. Pyrethroids are the only recommended compounds for nets treatment because they are fast-acting insecticides with low mammalian toxicity. However, there is growing concern that pyrethroid resistance may threaten the sustainability of ITN scaling-up programmes. Here, insecticide susceptibility was investigated in Anopheles gambiae sensu lato from an area of large scale ITN distribution programme in south-western Chad. Methods Susceptibility to 4% DDT, 0.05% deltamethrin, 0.75% permethrin, 0.1% bendiocarb and 5% malathion was assessed using the WHO standard procedures for adult mosquitoes. Tests were carried out with two to four days-old, non-engorged female mosquitoes. The An. gambiae Kisumu strain was used as a reference. Knockdown effect was recorded every 5 min and mortality scored 24 h after exposure. Mosquitoes were identified to species and molecular form by PCR-RFLP and genotypes at the kdr locus were determined in surviving specimens by Hot Oligonucleotide Ligation Assay (HOLA. Results During this survey, full susceptibility to malathion was recorded in all samples. Reduced susceptibility to bendiocarb (mortality rate of 96.1% was found in one sample out of nine assayed. Increased tolerance to pyrethroids was detected in most samples (8/9 with mortality rates ranging from 70.2 to 96.6% for deltamethrin and from 26.7 to 96.3% for permethrin. Pyrethroid tolerance was not associated with a significant increase of knock-down times. Anopheles arabiensis was the predominant species of the An. gambiae complex in the study area, representing 75 to 100% of the samples. Screening for kdr mutations detected the L1014F mutation in 88.6% (N = 35 of surviving An. gambiae sensu stricto S form mosquitoes. All surviving An. arabiensis (N = 49 and M form An. gambiae s.s. (N = 1 carried the susceptible allele

  11. Three years of insecticide resistance monitoring in Anopheles gambiae in Burkina Faso: resistance on the rise?

    Directory of Open Access Journals (Sweden)

    Badolo Athanase

    2012-07-01

    Full Text Available Abstract Background and methods A longitudinal Anopheles gambiae s.l. insecticide-resistance monitoring programme was established in four sentinel sites in Burkina Faso. For three years, between 2008 and 2010, WHO diagnostic dose assays were used to measure the prevalence of resistance to all the major classes of insecticides at the beginning and end of the malaria transmission season. Species identification and genotyping for target site mutations was also performed and the sporozoite rate in adults determined. Results At the onset of the study, resistance to DDT and pyrethroids was already prevalent in An. gambiae s.l. from the south-west of the country but mosquitoes from the two sites in central Burkina Faso were largely susceptible. Within three years, DDT and permethrin resistance was established in all four sites. Carbamate and organophosphate resistance remains relatively rare and largely confined to the south-western areas although a small number of bendiocarb survivors were found in all sites by the final round of monitoring. The ace-1R target site resistance allele was present in all localities and its frequency exceeded 20% in 2010 in two of the sites. The frequency of the 1014F kdr mutation increased throughout the three years and by 2010, the frequency of 1014F in all sites combined was 0.02 in Anopheles arabiensis, 0.56 in An. gambiae M form and 0.96 in An. gambiae S form. This frequency did not differ significantly between the sites. The 1014S kdr allele was only found in An. arabiensis but its frequency increased significantly throughout the study (P = 0.0003 and in 2010 the 1014S allele frequency was 0.08 in An. arabiensis. Maximum sporozoite rates (12% were observed in Soumousso in 2009 and the difference between sites is significant for each year. Conclusion Pyrethroid and DDT resistance is now established in An. gambiae s.l. throughout Burkina Faso. Results from diagnostic dose assays are highly variable within and

  12. Change in composition of the Anopheles gambiae complex and its possible implications for the transmission of malaria and lymphatic filariasis in north-eastern Tanzania

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    Derua Yahya A

    2012-06-01

    Full Text Available Abstract Background A dramatic decline in the incidence of malaria due to Plasmodium falciparum infection in coastal East Africa has recently been reported to be paralleled (or even preceded by an equally dramatic decline in malaria vector density, despite absence of organized vector control. As part of investigations into possible causes for the change in vector population density, the present study analysed the Anopheles gambiae s.l. sibling species composition in north-eastern Tanzania. Methods The study was in two parts. The first compared current species complex composition in freshly caught An. gambiae s.l. complex from three villages to the composition reported from previous studies carried out 2–4 decades ago in the same villages. The second took advantage of a sample of archived dried An. gambiae s.l. complex specimens collected regularly from a fourth study village since 2005. Both fresh and archived dried specimens were identified to sibling species of the An. gambiae s.l. complex by PCR. The same specimens were moreover examined for Plasmodium falciparum and Wuchereria bancrofti infection by PCR. Results As in earlier studies, An. gambiae s.s., Anopheles merus and Anopheles arabiensis were identified as sibling species found in the area. However, both study parts indicated a marked change in sibling species composition over time. From being by far the most abundant in the past An. gambiae s.s. was now the most rare, whereas An. arabiensis had changed from being the most rare to the most common. P. falciparum infection was rarely detected in the examined specimens (and only in An. arabiensis whereas W. bancrofti infection was prevalent and detected in all three sibling species. Conclusion The study indicates that a major shift in An. gambiae s.l. sibling species composition has taken place in the study area in recent years. Combined with the earlier reported decline in overall malaria vector density, the study suggests that this

  13. Co-occurrence and distribution of East (L1014S) and West (L1014F) African knock-down resistance in Anopheles gambiae sensu lato population of Tanzania

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    Kabula, Bilali; Kisinza, William; Tungu, Patrick; Ndege, Chacha; Batengana, Benard; Kollo, Douglas; Malima, Robert; Kafuko, Jessica; Mohamed, Mahdi; Magesa, Stephen

    2014-01-01

    Objective Insecticide resistance molecular markers can provide sensitive indicators of resistance development in Anopheles vector populations. Assaying these makers is of paramount importance in the resistance monitoring programme. We investigated the presence and distribution of knock-down resistance (kdr) mutations in Anopheles gambiae s.l. in Tanzania. Methods Indoor-resting Anopheles mosquitoes were collected from 10 sites and tested for insecticide resistance using the standard WHO protocol. Polymerase chain reaction-based molecular diagnostics were used to genotype mosquitoes and detect kdr mutations. Results The An. gambiae tested were resistance to lambdacyhalothrin in Muheza, Arumeru and Muleba. Out of 350 An. gambiae s.l. genotyped, 35% were An. gambiae s.s. and 65% An. arabiensis. L1014S and L1014F mutations were detected in both An. gambiae s.s. and An. arabiensis. L1014S point mutation was found at the allelic frequency of 4–33%, while L1014F was at the allelic frequency 6–41%. The L1014S mutation was much associated with An. gambiae s.s. (χ2 = 23.41; P lambdacialotrina en Muheza, Arumeru y Muleba. De 350 An. gambiae s.l. genotipados, 35% eran An. gambiae s.s. y 65% eran An. arabiensis. Se detectaron mutaciones L1014S y L1014F tanto en An. gambiae s.s. como en An. arabiensis. La mutación puntual L1014S se encontró con una frecuencia alélica de 4-33%, mientras que L1014F tenía una frecuencia alélica de 6-14%. La mutación L1014S estaba ampliamente asociada a An. gambiae s.s. (Chi-Cuadrado = 23.41; P lambdacialotrina (P < 0.001). Conclusión La simultaneidad de mutaciones de L1014S y L1014F junto con informes de resistencia a los insecticidas sugiere que la resistencia a piretroides se está convirtiendo en un fenómeno común entre las poblaciones del vector de la malaria en Tanzania. La presencia de la mutación L1014F en estas poblaciones del Este de África indican la diseminación del gen a lo largo del continente africano

  14. [Mosquitoes (Diptera, Culicidae) of Smir marshes (northwest of Morocco): inventory and biotypology].

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    El Joubari, M; Louah, A; Himmi, O

    2014-02-01

    The Smir marshes are a favorable environment for the growth of many mosquitoes (Diptera, Culicidae). The inventory of Culicidae species reveals 14 species, is 33% of the species of Morocco, distributed in four genera: Culex, Culiseta, Ochlerotatus and Anopheles (with 5, 2, 5 and 2 species respectively) which Anopheles labranchiae, vector of the agent of the malaria in Morocco until 2004. In this study, we investigated the spatiotemporal mesological affinities and we tried to explain the biotypology of mosquito populations of the site. These analyzes revealed several groups of stations and species according to various parameters, especially salinity.

  15. Pyrethroid resistance in southern African Anopheles funestus extends to Likoma Island in Lake Malawi

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    Edwardes M

    2010-12-01

    Full Text Available Abstract Background A mosquito survey was carried out on the island of Likoma in Lake Malawi with a view to collecting baseline data to determine the feasibility of implementing an integrated malaria vector control programme. No vector control interventions are currently being applied on the island apart from the sporadic use of treated and untreated bed nets. Results Large numbers of Anopheles funestus were found resting inside houses. WHO susceptibility tests were carried out on wild caught females and 1-5 day old F-1 female progeny. Wild caught females were tested on deltamethrin (77.8% mortality and bendiocarb (56.4% mortality. Female progeny were tested on deltamethrin (41.4% mortality, permethrin (40.4%, bendiocarb (52.5%, propoxur (7.4%, malathion, fenitrothion, DDT, dieldrin (all 100% and pirimiphos-methyl (98.9%. The malaria parasite rate was 4.9%. A small number of Anopheles arabiensis were also collected. Conclusion This locality is 1,500 km north of the currently known distribution of pyrethroid resistant An. funestus in southern Africa. The susceptibility results mirror those found in southern Mozambique and South African populations, but are markedly different to An. funestus populations in Uganda, indicating that the Malawi resistance has spread from the south.

  16. Entomological indices of Anopheles gambiae sensu lato at a rural community in south-west Nigeria

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    M.A.E. Noutcha

    2009-02-01

    Full Text Available Background & objectives: Investigations were conducted to obtain key entomological indices of Anopheles gambiae s.l. at Igbo-Ora, a rural community in south-west Nigeria. Methods: Mosquitoes were caught daily for a week from rooms where tenants had slept the previous night in each of the four months June, July (2001, and August, September (2002. Anopheles gambiae s.l. sibling species were PCR-identified, the blood meal origin was determined by direct ELISA, and the circumsporozoite antigen by sandwich ELISA. Mean weekly rates were calculated. Results: The mean human biting rates were 0.90 and 1.6 in 2001 and 2002 respectively. The mean weekly anthropophilic rates for An. gambiae s.l. were 82 and 86% in 2001 and 2002 respectively; they were high in An. gambiae s.s., An. arabiensis and non-identified species in the complex. The mean weekly circumsporozoite rates were 6.70% in 2001 and 6.30% in 2002. The mean weekly entomological inoculation rates (EIR were 4.95 and 5.05 in 2001 and 2002 respectively; the seasonal (6-month rates were high: 128.7 in 2001 and 131.3 in 2002, compared to data from other rural communities on the continent. Interpretation & conclusion: The implications of these findings on the role of An. gambiae s.l. in the holoendemicity of malaria at Igbo-Ora are discussed.

  17. Dynamics of insecticide resistance in malaria vectors in Benin: first evidence of the presence of L1014S kdr mutation in Anopheles gambiae from West Africa

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    Ranson Hilary

    2011-09-01

    Full Text Available Abstract Background Insecticide resistance monitoring is essential to help national programmers to implement more effective and sustainable malaria control strategies in endemic countries. This study reported the spatial and seasonal variations of insecticide resistance in malaria vectors in Benin, West Africa. Methods Anopheles gambiae s.l populations were collected from October 2008 to June 2010 in four sites selected on the basis of different use of insecticides and environment. WHO susceptibility tests were carried out to detect resistance to DDT, fenitrothion, bendiocarb, permethrin and deltamethrin. The synergist piperonyl butoxide was used to assess the role of non-target site mechanisms in pyrethroid resistance. Anopheles gambiae mosquitoes were identified to species and to molecular M and S forms using PCR techniques. Molecular and biochemical assays were carried out to determine kdr and Ace.1R allelic frequencies and activity of the detoxification enzymes. Results Throughout the surveys very high levels of mortality to bendiocarb and fenitrothion were observed in An. gambiae s.l. populations. However, high frequencies of resistance to DDT and pyrethroids were seen in both M and S form of An. gambiae s.s. and Anopheles arabiensis. PBO increased the toxicity of permethrin and restored almost full susceptibility to deltamethrin. Anopheles gambiae s.l. mosquitoes from Cotonou and Malanville showed higher oxidase activity compared to the Kisumu susceptible strain in 2009, whereas the esterase activity was higher in the mosquitoes from Bohicon in both 2008 and 2009. A high frequency of 1014F kdr allele was initially showed in An. gambiae from Cotonou and Tori-Bossito whereas it increased in mosquitoes from Bohicon and Malanville during the second year. For the first time the L1014S kdr mutation was found in An. arabiensis in Benin. The ace.1R mutation was almost absent in An. gambiae s.l. Conclusion Pyrethroid and DDT resistance is

  18. Use of carbon-13 as a population marker for Anopheles arabiensis in a sterile insect technique (SIT) context

    NARCIS (Netherlands)

    Hood-Nowotny, R.C.; Mayr, L.; Knols, B.G.J.

    2006-01-01

    Background - Monitoring of sterile to wild insect ratios in field populations can be useful to follow the progress in genetic control programmes such as the Sterile Insect Technique (SIT). Of the numerous methods for marking insects most are not suitable for use in mass rearing and mass release. Sui

  19. Screening for adulticidal activity against Anopheles arabiensis in ten plants used as mosquito repellent in South Africa

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    Mavundza, Edison J; Maharaj, Rajendra; Chukwujekwu, Jude C; Finnie, Jeffrey F; Staden, Johannes Van

    2014-01-01

    Background Due to the development of resistance to synthetic insecticides, adverse effects to human health, non-target organisms and the environment, there is an urgent need to develop new insecticides, which are effective, safe, biodegrable and target-specific. This study was undertaken to evaluate the adulticidal activity of 10 plants used traditionally as mosquito repellents in South Africa. Methods The dried plant materials were extracted with dichloromethane (DCM) and ethanol (EtOH). The...

  20. The susceptibility of five African Anopheles species to Anabaena PCC 7120 expressing Bacillus thuringiensis subsp. israelensis mosquitocidal cry genes

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    Ketseoglou Irene

    2012-10-01

    Full Text Available Abstract Background Malaria, one of the leading causes of death in Africa, is transmitted by the bite of an infected female Anopheles mosquito. Problems associated with the development of resistance to chemical insecticides and concerns about the non-target effects and persistence of chemical insecticides have prompted the development of environmentally friendly mosquito control agents. The aim of this study was to evaluate the larvicidal activity of a genetically engineered cyanobacterium, Anabaena PCC 7120#11, against five African Anopheles species in laboratory bioassays. Findings There were significant differences in the susceptibility of the anopheline species to PCC 7120#11. The ranking of the larvicidal activity of PCC 7120#11 against species in the An. gambiae complex was: An. merus An. arabiensis An. gambiae An. quadriannulatus, where 50. The LC50 of PCC 7120#11 against the important malaria vectors An. gambiae and An. arabiensis was 12.3 × 105 cells/ml and 8.10 × 105 cells/ml, respectively. PCC 7120#11 was not effective against An. funestus, with less than 50% mortality obtained at concentrations as high as 3.20 × 107 cells/ml. Conclusions PCC 7120#11 exhibited good larvicidal activity against larvae of the An. gambiae complex, but relatively weak larvicidal activity against An. funestus. The study has highlighted the importance of evaluating a novel mosquitocidal agent against a range of malaria vectors so as to obtain a clear understanding of the agent’s spectrum of activity and potential as a vector control agent.

  1. Mosaic genome architecture of the Anopheles gambiae species complex.

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    Rui Wang-Sattler

    Full Text Available BACKGROUND: Attempts over the last three decades to reconstruct the phylogenetic history of the Anopheles gambiae species complex have been important for developing better strategies to control malaria transmission. METHODOLOGY: We used fingerprint genotyping data from 414 field-collected female mosquitoes at 42 microsatellite loci to infer the evolutionary relationships of four species in the A. gambiae complex, the two major malaria vectors A. gambiae sensu stricto (A. gambiae s.s. and A. arabiensis, as well as two minor vectors, A. merus and A. melas. PRINCIPAL FINDINGS: We identify six taxonomic units, including a clear separation of West and East Africa A. gambiae s.s. S molecular forms. We show that the phylogenetic relationships vary widely between different genomic regions, thus demonstrating the mosaic nature of the genome of these species. The two major malaria vectors are closely related and closer to A. merus than to A. melas at the genome-wide level, which is also true if only autosomes are considered. However, within the Xag inversion region of the X chromosome, the M and two S molecular forms are most similar to A. merus. Near the X centromere, outside the Xag region, the two S forms are highly dissimilar to the other taxa. Furthermore, our data suggest that the centromeric region of chromosome 3 is a strong discriminator between the major and minor malaria vectors. CONCLUSIONS: Although further studies are needed to elucidate the basis of the phylogenetic variation among the different regions of the genome, the preponderance of sympatric admixtures among taxa strongly favor introgression of different genomic regions between species, rather than lineage sorting of ancestral polymorphism, as a possible mechanism.

  2. [Updated inventory of mosquitoes (Diptera: Culicidae) of the island of La Réunion, Indian Ocean].

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    Boussès, P; Dehecq, J S; Brengues, C; Fontenille, D

    2013-05-01

    A literature analysis coupled with new entomological surveys conducted between 2009 and 2012 led to changes in the list of mosquito species present on the island of La Réunion. Using morphological criteria, Orthopodomyia arboricollis is replaced by Or. reunionensis. On the basis of morphometrical and genetic criteria, Culex univittatus is replaced by Cx. neavei. Cx. poicilipes, which was already reported missing 40 years ago, has not been found again. Anopheles arabiensis is confirmed as the only species of the Gambiae complex present on the island. Thus, twelve species are currently known. For each of them, elements of taxonomic, biological and medical interest are listed. An. arabiensis is a major vector of human Plasmodium (last case of indigenous malaria in 1967). In the Indian Ocean, Aedes albopictus and Ae. aegypti both are competent for transmitting dengue and chikungunya viruses. In Africa, Cx. quinquefasciatus transmits Wuchereria bancrofti and Cx. neavei transmits the Sindbis virus; both species also transmit the West Nile virus. Cx. tritaeniorhynchus is the major vector of Japanese Encephalitis virus in Asia. Two species are endemic (Ae. dufouri and Or. reunionensis), the ten other ones are also found in Madagascar and on the African continent (An. coustani, An. arabiensis, Ae. fowleri, Cx. tritaeniorhynchus, Cx. neavei, Cx. insignis, Lutzia tigripes), with three of them having also a cosmopolitan distribution (Ae. aegypti, Ae. albopictus and Cx. quinquefasciatus). Among the twelve recorded taxa, eight species are anthropophilic, three are supposedly zoophilic and one is a predatory species. No new invasive anthropophilic species did settle on the island. Updated identification keys of larval and adult stages are proposed.

  3. Multiple insecticide resistance mechanisms in Anopheles gambiae s.l. populations from Cameroon, Central Africa

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    Nwane Philippe

    2013-02-01

    Full Text Available Abstract Background Increasing incidence of DDT and pyrethroid resistance in Anopheles mosquitoes is seen as a limiting factor for malaria vector control. The current study aimed at an in-depth characterization of An. gambiae s.l. resistance to insecticides in Cameroon, in order to guide malaria vector control interventions. Methods Anopheles gambiae s.l. mosquitoes were collected as larvae and pupae from six localities spread throughout the four main biogeographical domains of Cameroon and reared to adults in insectaries. Standard WHO insecticide susceptibility tests were carried out with 4% DDT, 0.75% permethrin and 0.05% deltamethrin. Mortality rates and knockdown times (kdt50 and kdt95 were determined and the effect of pre-exposure to the synergists DEF, DEM and PBO was assessed. Tested mosquitoes were identified to species and molecular forms (M or S using PCR-RFLP. The hot ligation method was used to depict kdr mutations and biochemical assays were conducted to assess detoxifying enzyme activities. Results The An. arabiensis population from Pitoa was fully susceptible to DDT and permethrin (mortality rates > 98% and showed reduced susceptibility to deltamethrin. Resistance to DDT was widespread in An. gambiae s.s. populations and heterogeneous levels of susceptibility to permethrin and deltamethrin were observed. In many cases, prior exposure to synergists partially restored insecticide knockdown effect and increased mortality rates, suggesting a role of detoxifying enzymes in increasing mosquito survival upon challenge by pyrethroids and, to a lower extent DDT. The distribution of kdr alleles suggested a major role of kdr-based resistance in the S form of An. gambiae. In biochemical tests, all but one mosquito population overexpressed P450 activity, whereas baseline GST activity was low and similar in all field mosquito populations and in the control. Conclusion In Cameroon, multiple resistance mechanisms segregate in the S form of An

  4. Male motion coordination in swarming Anopheles gambiae and Anopheles coluzzii

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    The Anopheles gambiae species complex comprises the primary vectors of malaria in much of sub-Saharan Africa; most of the mating in these species occurs in swarms composed almost entirely of males. Intermittent, parallel flight patterns in such swarms have been observed, but a detailed description o...

  5. Longitudinal evaluation of Ocimum and other plants effects on the feeding behavioral response of mosquitoes (Diptera: Culicidae in the field in Tanzania

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    Tenu Filemoni

    2008-10-01

    Full Text Available Abstract Background The use of repellent materials from plants against nuisance insects is common with great potential to compliment existing malaria control programmes and this requires evaluation in the field. Ocimum plant species, Ocimum suave (Willd and O. kilimandscharicum (Guerke materials and their essential oils extracted by steam distillation were evaluated in the field and experimental huts for repellence, exophily and feeding inhibition effects against three mosquito species, Anopheles arabiensis (Patton, An. gambiae ss (Giles and Culex quinquefasciatus (Say. The protective effect of essential oils from Ocimum plants were compared with N, N-diethly-3- methylbenzamide (DEET, a standard synthetic repellent. Also, the protective effect of fumigation by burning of repellent plants; Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara were tested in experimental huts and selected local houses. Results In the field, protection by Ocimum plants from mosquito bites was high and there was small variation among different mosquito species. Protection efficiency was 93.4%, 91.98% and 89.75% for An. arabiensis while for Cx. quinquefaciatus it was 91.30%, 88.65% and 90.50% for DEET, Ocimum suave and O. kilimandscharicum respectively. In the experimental hut, deterrence induced by burning of Ocimum and other plants ranged from 73.1.0% to 81.9% for An. arabiensis and 56.5% to 67.8% for Cx. quinquefaciatus, while feeding inhibition was 61.1% to 100% for An. arabiensis and 50% to 100% for Cx. quinquefaciatus. Evaluations under field conditions confirmed high protective efficacy, enhanced feeding inhibition and house entry inhibition (Deterrence. Conclusion This study shows the potential of Ocimum suave and Ocimum kilimandscharicum crude extracts and whole plants of Ocimum suave, Ocimum kilimandscharicum, Azadirachta indica, Eucalyptus globules and Lantana camara for use in protecting against human biting

  6. Evolutionary dynamics of the Ty3/gypsy LTR retrotransposons in the genome of Anopheles gambiae.

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    Jose Manuel C Tubio

    Full Text Available Ty3/gypsy elements represent one of the most abundant and diverse LTR-retrotransposon (LTRr groups in the Anopheles gambiae genome, but their evolutionary dynamics have not been explored in detail. Here, we conduct an in silico analysis of the distribution and abundance of the full complement of 1045 copies in the updated AgamP3 assembly. Chromosomal distribution of Ty3/gypsy elements is inversely related to arm length, with densities being greatest on the X, and greater on the short versus long arms of both autosomes. Taking into account the different heterochromatic and euchromatic compartments of the genome, our data suggest that the relative abundance of Ty3/gypsy LTRrs along each chromosome arm is determined mainly by the different proportions of heterochromatin, particularly pericentric heterochromatin, relative to total arm length. Additionally, the breakpoint regions of chromosomal inversion 2La appears to be a haven for LTRrs. These elements are underrepresented more than 7-fold in euchromatin, where 33% of the Ty3/gypsy copies are associated with genes. The euchromatin on chromosome 3R shows a faster turnover rate of Ty3/gypsy elements, characterized by a deficit of proviral sequences and the lowest average sequence divergence of any autosomal region analyzed in this study. This probably reflects a principal role of purifying selection against insertion for the preservation of longer conserved syntenyc blocks with adaptive importance located in 3R. Although some Ty3/gypsy LTRrs show evidence of recent activity, an important fraction are inactive remnants of relatively ancient insertions apparently subject to genetic drift. Consistent with these computational predictions, an analysis of the occupancy rate of putatively older insertions in natural populations suggested that the degenerate copies have been fixed across the species range in this mosquito, and also are shared with the sibling species Anopheles arabiensis.

  7. Kdr-based insecticide resistance in Anopheles gambiae s.s populations in

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    Nwane Philippe

    2011-10-01

    Full Text Available Abstract Background The spread of insecticide resistance in the malaria mosquito, Anopheles gambiae is a serious threat for current vector control strategies which rely on the use of insecticides. Two mutations at position 1014 of the S6 transmembrane segment of domain II in the voltage gated sodium channel, known as kdr (knockdown resistance mutations leading to a change of a Leucine to a Phenylalanine (L1014F or to a Serine (L1014S confer resistance to DDT and pyrethroid insecticides in the insect. This paper presents the current distribution of the kdr alleles in wild Anopheles gambiae populations in Cameroon. Results A total of 1,405 anopheline mosquitoes were collected from 21 localities throughout Cameroon and identified as An. gambiae (N = 1,248; 88.8%, An. arabiensis (N = 120; 8.5% and An. melas (N = 37; 2.6%. Both kdr alleles 1014F and 1014S were identified in the M and S molecular forms of An. gambiae s.s. The frequency of the 1014F allele ranged from 1.7 to 18% in the M-form, and from 2 to 90% in the S-form. The 1014S allele ranged from 3-15% in the S-form and in the M-form its value was below 3%. Some specimens were found to carry both resistant kdr alleles. Conclusion This study provides an updated distribution map of the kdr alleles in wild An. gambiae populations in Cameroon. The co-occurrence of both alleles in malaria mosquito vectors in diverse ecological zones of the country may be critical for the planning and implementation of malaria vector control interventions based on IRS and ITNs, as currently ongoing in Cameroon.

  8. A new mtDNA COI gene lineage closely related to Anopheles janconnae of the Albitarsis complex in the Caribbean region of Colombia

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    Lina A Gutiérrez

    2010-12-01

    Full Text Available An understanding of the taxonomic status and vector distribution of anophelines is crucial in controlling malaria. Previous phylogenetic analyses have supported the description of six species of the Neotropical malaria vector Anopheles (Nyssorhynchus albitarsis s.l. (Diptera: Culicidae: An. albitarsis, Anopheles deaneorum, Anopheles marajoara, Anopheles oryzalimnetes, Anopheles janconnae and An. albitarsis F. To evaluate the taxonomic status of An. albitarsis s.l. mosquitoes collected in various localities in the Colombian Caribbean region, specimens were analyzed using the complete mitochondrial DNA cytochrome oxidase I (COI gene, the ribosomal DNA (rDNA internal transcribed spacer 2 (ITS2 region and partial nuclear DNA white gene sequences. Phylogenetic analyses of the COI gene sequences detected a new lineage closely related to An. janconnae in the Caribbean region of Colombia and determined its position relative to the other members of the complex. However, the ITS2 and white gene sequences lacked sufficient resolution to support a new lineage closely related to An. janconnae or the An. janconnae clade. The possible involvement of this new lineage in malaria transmission in Colombia remains unknown, but its phylogenetic closeness to An. janconnae, which has been implicated in local malaria transmission in Brazil, is intriguing.

  9. The population genomics of trans-specific inversion polymorphisms in Anopheles gambiae.

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    White, Bradley J; Cheng, Changde; Sangaré, Djibril; Lobo, Neil F; Collins, Frank H; Besansky, Nora J

    2009-09-01

    In the malaria mosquito Anopheles gambiae polymorphic chromosomal inversions may play an important role in adaptation to environmental variation. Recently, we used microarray-based divergence mapping combined with targeted resequencing to map nucleotide differentiation between alternative arrangements of the 2La inversion. Here, we applied the same technique to four different polymorphic inversions on the 2R chromosome of An. gambiae. Surprisingly, divergence was much lower between alternative arrangements for all 2R inversions when compared to the 2La inversion. For one of the rearrangements, 2Ru, we successfully mapped a very small region (approximately 100 kb) of elevated divergence. For the other three rearrangements, we did not identify any regions of significantly high divergence, despite ample independent evidence from natural populations of geographic clines and seasonal cycling, and stable heterotic polymorphisms in laboratory populations. If these inversions are the targets of selection as hypothesized, we suggest that divergence between rearrangements may have escaped detection due to retained ancestral polymorphism in the case of the youngest 2R rearrangements and to extensive gene flux in the older 2R inversion systems that segregate in both An. gambiae and its sibling species An. arabiensis. PMID:19581444

  10. Characterization of anopheline (Diptera: Culicidae larval habitats in Nouakchott, Mauritania

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    O. Ahmedou Salem Mohamed Salem

    2013-12-01

    Full Text Available Background & objectives: Despite the increasing number of reported autochthonous malaria cases in Nouakchott and the identification of Anopheles arabiensis as the major malaria vector in this Saharan city, anopheline larval habitats have never been identified so far. The objective of this study was to identify and characterize anopheline larval habitats in Nouakchott. Methods: During September and October 2012, samples from pools of rainwater, water discharged from standpipes and household drinking water tanks in the districts of Dar Naim, Teyarett and Arafat were analyzed for the presence/absence of anopheline larvae and physicochemical characterization of breeding habitats. Results: Of the 51 prospected water bodies, eight consisting of seven water discharged from standpipes and one household drinking water tank were productive for Anopheles sp. All emerged anopheline mosquitoes from the positive dipping were morphologically identified as members of the An. gambiae complex. Multivariate regression analyses showed that a salinity up to 0.1 g/l and a shaded situation were respectively protective factors against high larval density in breeding sites (adjusted odds ratio = 0.62, 95% CI [0.44-0.87], p = 0.0052 and adjusted odds ratio = 0.56, 95% CI [0.44-0.71, p <0.0001] and a pH up to 7.61 was a risk factor for high larval density in breeding sites (adjusted odds ratio = 1.56, 95% CI [1.25-1.95], p = 0.0001. Interpretation & conclusion: The study demonstrated in Nouakchott that despite an arid and dry climate, human practices have contributed to the establishment of favourable environmental conditions for the development of anopheline mosquitoes and, therefore, maintaining malaria transmission in this Saharan city. The core malaria vector control intervention as the use of long-lasting insecicidal nets (LLINs could be complemented in Nouakchott by larval source control. In this area, appropriate larval control measures may be recommended in line

  11. Mosquito repellent action of Blumea lacera (Asteraceae against Anopheles stephensi and Culex quinquefasciatus.

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    S.P. Singh

    2014-03-01

    Full Text Available Petroleum ether extract of Blumea lacera was screened under laboratory conditions for repellent activity against mosquito vector Anopheles stephensi Liston and Culex quinquefasciatus Say (Diptera: Culicidae. The repellent activity of Blumea lacera extract was tested against mosquitoes in comparison with the DEET, which was used as a positive control. Results obtained from the laboratory experiment showed that the extract was effective against mosquito vectors even at a low dose. A direct relationship was observed with concentrations of Blumea lacera extract and the repellent activity. Percent repellency obtained at 6% concentration of theextract against An. stephensi and Cx. quinquefasciatus were 97and 98% at 0 hour and 78.8 and 76.2% after 6 hrs. DEET-2% however showed 100% repellency against An. stephensi and against Cx. quinquefasciatus up to 4 hours and 1 hour, respectively. These results show that Blumea lacera extract has the potential as an effective mosquito repellent.

  12. Genetic Study of Propoxur Resistance—A Carbamate Insecticide in the Malaria Mosquito, Anopheles stephensi Liston

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    D. Sanil

    2010-01-01

    Full Text Available Anopheles stephensi Liston (Diptera: Culicidae is the urban vector of malaria in the Indian subcontinent and several countries of the Middle East. The genetics of propoxur resistance (pr in An. stephensi larvae was studied to determine its mode of inheritance. A diagnostic dose of 0.01 mg/L as recommended by WHO was used to establish homozygous resistant and susceptible strains. Reciprocal crosses between the resistant and susceptible strains showed an F1 generation of incomplete dominance. The progenies of backcrosses to susceptible parents were in 1 : 1 ratio of the same phenotypes as the parents and hybrids involved. The dosage mortality (d-m lines were constructed for each one of the crosses, and the degree of dominance was calculated. It is concluded that propoxur resistance in An. stephensi larvae is due to monofactorial inheritance with incomplete dominance and is autosomal in nature.

  13. Ecological niche partitioning between Anopheles gambiae molecular forms in Cameroon: the ecological side of speciation

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    Fotsing Jean-Marie

    2009-05-01

    Full Text Available Abstract Background Speciation among members of the Anopheles gambiae complex is thought to be promoted by disruptive selection and ecological divergence acting on sets of adaptation genes protected from recombination by polymorphic paracentric chromosomal inversions. However, shared chromosomal polymorphisms between the M and S molecular forms of An. gambiae and insufficient information about their relationship with ecological divergence challenge this view. We used Geographic Information Systems, Ecological Niche Factor Analysis, and Bayesian multilocus genetic clustering to explore the nature and extent of ecological and chromosomal differentiation of M and S across all the biogeographic domains of Cameroon in Central Africa, in order to understand the role of chromosomal arrangements in ecological specialisation within and among molecular forms. Results Species distribution modelling with presence-only data revealed differences in the ecological niche of both molecular forms and the sibling species, An. arabiensis. The fundamental environmental envelope of the two molecular forms, however, overlapped to a large extent in the rainforest, where they occurred in sympatry. The S form had the greatest niche breadth of all three taxa, whereas An. arabiensis and the M form had the smallest niche overlap. Correspondence analysis of M and S karyotypes confirmed that molecular forms shared similar combinations of chromosomal inversion arrangements in response to the eco-climatic gradient defining the main biogeographic domains occurring across Cameroon. Savanna karyotypes of M and S, however, segregated along the smaller-scale environmental gradient defined by the second ordination axis. Population structure analysis identified three chromosomal clusters, each containing a mixture of M and S specimens. In both M and S, alternative karyotypes were segregating in contrasted environments, in agreement with a strong ecological adaptive value of

  14. Wide cross-reactivity between Anopheles gambiae and Anopheles funestus SG6 salivary proteins supports exploitation of gSG6 as a marker of human exposure to major malaria vectors in tropical Africa

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    Petrarca Vincenzo

    2011-07-01

    Full Text Available Abstract Background The Anopheles gambiae gSG6 is an anopheline-specific salivary protein which helps female mosquitoes to efficiently feed on blood. Besides its role in haematophagy, gSG6 is immunogenic and elicits in exposed individuals an IgG response, which may be used as indicator of exposure to the main African malaria vector A. gambiae. However, malaria transmission in tropical Africa is sustained by three main vectors (A. gambiae, Anopheles arabiensis and Anopheles funestus and a general marker, reflecting exposure to at least these three species, would be especially valuable. The SG6 protein is highly conserved within the A. gambiae species complex whereas the A. funestus homologue, fSG6, is more divergent (80% identity with gSG6. The aim of this study was to evaluate cross-reactivity of human sera to gSG6 and fSG6. Methods The A. funestus SG6 protein was expressed/purified and the humoral response to gSG6, fSG6 and a combination of the two antigens was compared in a population from a malaria hyperendemic area of Burkina Faso where both vectors were present, although with a large A. gambiae prevalence (>75%. Sera collected at the beginning and at the end of the high transmission/rainy season, as well as during the following low transmission/dry season, were analysed. Results According to previous observations, both anti-SG6 IgG level and prevalence decreased during the low transmission/dry season and showed a typical age-dependent pattern. No significant difference in the response to the two antigens was found, although their combined use yielded in most cases higher IgG level. Conclusions Comparative analysis of gSG6 and fSG6 immunogenicity to humans suggests the occurrence of a wide cross-reactivity, even though the two proteins carry species-specific epitopes. This study supports the use of gSG6 as reliable indicator of exposure to the three main African malaria vectors, a marker which may be useful to monitor malaria transmission

  15. Role of Culex and Anopheles mosquito species as potential vectors of rift valley fever virus in Sudan outbreak, 2007

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    Galal Fatma H

    2010-03-01

    Full Text Available Abstract Background Rift Valley fever (RVF is an acute febrile arthropod-borne viral disease of man and animals caused by a member of the Phlebovirus genus, one of the five genera in the family Bunyaviridae. RVF virus (RVFV is transmitted between animals and human by mosquitoes, particularly those belonging to the Culex, Anopheles and Aedes genera. Methods Experiments were designed during RVF outbreak, 2007 in Sudan to provide an answer about many raised questions about the estimated role of vector in RVFV epidemiology. During this study, adult and immature mosquito species were collected from Khartoum and White Nile states, identified and species abundance was calculated. All samples were frozen individually for further virus detection. Total RNA was extracted from individual insects and RVF virus was detected from Culex, Anopheles and Aedes species using RT-PCR. In addition, data were collected about human cases up to November 24th, 2007 to asses the situation of the disease in affected states. Furthermore, a historical background of the RVF outbreaks was discussed in relation to global climatic anomalies and incriminated vector species. Results A total of 978 mosquitoes, belonging to 3 genera and 7 species, were collected during Sudan outbreak, 2007. Anopheles gambiae arabiensis was the most frequent species (80.7% in White Nile state. Meanwhile, Cx. pipiens complex was the most abundant species (91.2% in Khartoum state. RT-PCR was used and successfully amplified 551 bp within the M segment of the tripartite negative-sense single stranded RNA genome of RVFV. The virus was detected in female, male and larval stages of Culex and Anopheles species. The most affected human age interval was 15-29 years old followed by ≥ 45 years old, 30-44 years old, and then 5-14 years old. Regarding to the profession, housewives followed by farmers, students, shepherd, workers and the free were more vulnerable to the infection. Furthermore, connection between

  16. Environmental factors associated with larval habitats of anopheline mosquitoes (Diptera: Culicidae in irrigation and major drainage areas in the middle course of the Rift Valley, central Ethiopia

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    Oljira Kenea, Meshesha Balkew & Teshome Gebre-Michael

    2011-06-01

    Full Text Available Background & objectives: Larval control is an integral part of malaria vector management in Ethiopia andelsewhere. For effective larval control, a sound understanding of the factors responsible for spatio-temporalvariation in larval production is essential. A study was thus conducted to characterize larval habitats of anophelinemosquitoes in irrigation and major drainage areas between Adami Tulu and Meki towns, in the middle course ofthe Ethiopian Rift Valley.Methods: Aquatic habitats were sampled for anopheline larvae and the associated environmental variables(water temperature, turbidity, water current, water pH and other variables were measured, characterized andanalyzed.Results: Microscopic identification of the late instars (III and IV of anopheline larvae collected throughout thestudy period yielded nearly 47.6% Anopheles pharoensis, 32.1% An. arabiensis, 17.1% An. squamosus and only3.2% of other species (An. coustani and An. cinereus. Larvae of the local malaria vectors, An. arabiensis andAn. pharoensis were most abundantly sampled from sand pools and natural swamps, respectively. Logisticregression analysis detected four best predictor variables associated with larval abundance of malaria vectorspecies. Thus, relative abundance of An. arabiensis larvae was significantly and inversely associated with aquaticvegetation and water current, whereas the relative abundance of An. pharoensis larvae was significantly andpositively associated with water temperature and the presence of algae in the water bodies.Conclusion: Dry season anopheline larval habitats such as riverine sand pools that are created and maintainedby perennial water bodies and their associated water development projects need to be considered in vectorcontrol operations.

  17. Reconsideration of Anopheles rivulorum as a vector of Plasmodium falciparum in western Kenya: some evidence from biting time, blood preference, sporozoite positive rate, and pyrethroid resistance

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    Kawada Hitoshi

    2012-10-01

    Full Text Available Abstract Background Anopheles gambiae, An. arabiensis, and An. funestus are widespread malaria vectors in Africa. Anopheles rivulorum is the next most widespread species in the An. funestus group. The role of An. rivulorum as a malaria vector has not been fully studied, although it has been found to be a minor or opportunistic transmitter of Plasmodium falciparum. Methods Mosquitoes were collected indoors over a 12-hour period using a light source attached to a rotating bottle collector in order to determine peak activity times and to provide DNA for meal source identification. Gravid female mosquitoes were collected indoors via an aspirator to generate F1 progeny for testing insecticidal susceptibility. Blood meal sources were identified using a multiplexed PCR assay for human and bovine cytochrome-B, and by matching sequences generated with primers targeting vertebrate and mammalian cytochrome-B segments to the Genbank database. Results Anopheles rivulorum fed on human blood in the early evening between 18:00 and 20:00, when insecticide-treated bed nets are not in use, and the presence of Plasmodium falciparum sporozoites in 0.70% of the An. rivulorum individuals tested was demonstrated. Susceptibility to permethrin, deltamethrin, and DDT is higher in An. rivulorum (84.8%, 91.4%, and 100%, respectively than in An. funestus s.s. (36.8%, 36.4%, and 70%, respectively, whereas mortality rates for propoxur and fenitrothion were 100% for both species. Resistance to pyrethroids was very high in An. funestus s.s. and the potential of the development of high resistance was suspected in An. rivulorum. Conclusion Given the tendency for An. rivulorum to be active early in the evening, the presence of P. falciparum in the species, and the potential for the development of pyrethroid resistance, we strongly advocate reconsideration of the latent ability of this species as an epidemiologically important malaria vector.

  18. Diptera. Chapter 10

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    Marcela Skuhravá

    2010-07-01

    Full Text Available Of the 19,400 native species and 125 families forming the European diptera fauna, 98 species (less than 0.5% in 22 families are alien to Europe. These aliens constitute 66 species (18 families of the suborder Brachycera and 32 species (4 families of the suborder Nematocera. By family in this category, there are 23 Cecidomyiidae species, 18 Drosophilidae, nine Phoridae, eight Tachinidae and seven Culicidae. Another 32 fly species belonging to five families are considered to be alien in Europe. These invasives native to other European countries are composed of 14 species of Cecidomyiidae, seven Syrphidae, five Culicidae and three species each of Anthomyiidae and Tephritidae. The date of the first record in Europe is known for 84 alien species. Arrivals of alien species of Diptera have accelerated rapidly since the second half of the 20th century. North America appears to be the dominant contributor of the alien flies. The majority of alien Diptera were introduced into or within Europe unintentionally, with only three predators released intentionally for biological control. Alien Diptera are predominantly phytophagous (35.6%, while a lesser portion are zoophagous (28.6% or detrivorous/mycetophagous (29.6%. Ecological impacts on native fauna and flora have not been documented for any of the alien species established in Europe. However, 14 alien species have economic impacts on crops.

  19. Fauna europaea: Diptera - brachycera.

    Science.gov (United States)

    Pape, Thomas; Beuk, Paul; Pont, Adrian Charles; Shatalkin, Anatole I; Ozerov, Andrey L; Woźnica, Andrzej J; Merz, Bernhard; Bystrowski, Cezary; Raper, Chris; Bergström, Christer; Kehlmaier, Christian; Clements, David K; Greathead, David; Kameneva, Elena Petrovna; Nartshuk, Emilia; Petersen, Frederik T; Weber, Gisela; Bächli, Gerhard; Geller-Grimm, Fritz; Van de Weyer, Guy; Tschorsnig, Hans-Peter; de Jong, Herman; van Zuijlen, Jan-Willem; Vaňhara, Jaromír; Roháček, Jindřich; Ziegler, Joachim; Majer, József; Hůrka, Karel; Holston, Kevin; Rognes, Knut; Greve-Jensen, Lita; Munari, Lorenzo; de Meyer, Marc; Pollet, Marc; Speight, Martin C D; Ebejer, Martin John; Martinez, Michel; Carles-Tolrá, Miguel; Földvári, Mihály; Chvála, Milan; Barták, Miroslav; Evenhuis, Neal L; Chandler, Peter J; Cerretti, Pierfilippo; Meier, Rudolf; Rozkosny, Rudolf; Prescher, Sabine; Gaimari, Stephen D; Zatwarnicki, Tadeusz; Zeegers, Theo; Dikow, Torsten; Korneyev, Valery A; Richter, Vera Andreevna; Michelsen, Verner; Tanasijtshuk, Vitali N; Mathis, Wayne N; Hubenov, Zdravko; de Jong, Yde

    2015-01-01

    Fauna Europaea provides a public web-service with an index of scientific names (including important synonyms) of all extant multicellular European terrestrial and freshwater animals and their geographical distribution at the level of countries and major islands (east of the Urals and excluding the Caucasus region). The Fauna Europaea project comprises about 230,000 taxonomic names, including 130,000 accepted species and 14,000 accepted subspecies, which is much more than the originally projected number of 100,000 species. Fauna Europaea represents a huge effort by more than 400 contributing taxonomic specialists throughout Europe and is a unique (standard) reference suitable for many user communities in science, government, industry, nature conservation and education. The Diptera-Brachycera is one of the 58 Fauna Europaea major taxonomic groups, and data have been compiled by a network of 55 specialists. Within the two-winged insects (Diptera), the Brachycera constitute a monophyletic group, which is generally given rank of suborder. The Brachycera may be classified into the probably paraphyletic 'lower brachyceran grade' and the monophyletic Eremoneura. The latter contains the Empidoidea, the Apystomyioidea with a single Nearctic species, and the Cyclorrhapha, which in turn is divided into the paraphyletic 'aschizan grade' and the monophyletic Schizophora. The latter is traditionally divided into the paraphyletic 'acalyptrate grade' and the monophyletic Calyptratae. Our knowledge of the European fauna of Diptera-Brachycera varies tremendously among families, from the reasonably well known hoverflies (Syrphidae) to the extremely poorly known scuttle flies (Phoridae). There has been a steady growth in our knowledge of European Diptera for the last two centuries, with no apparent slow down, but there is a shift towards a larger fraction of the new species being found among the families of the nematoceran grade (lower Diptera), which due to a larger number of small

  20. Molecular evolution of immune genes in the malaria mosquito Anopheles gambiae.

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    Tovi Lehmann

    Full Text Available BACKGROUND: As pathogens that circumvent the host immune response are favoured by selection, so are host alleles that reduce parasite load. Such evolutionary processes leave their signature on the genes involved. Deciphering modes of selection operating on immune genes might reveal the nature of host-pathogen interactions and factors that govern susceptibility in host populations. Such understanding would have important public health implications. METHODOLOGY/FINDINGS: We analyzed polymorphisms in four mosquito immune genes (SP14D1, GNBP, defensin, and gambicin to decipher selection effects, presumably mediated by pathogens. Using samples of Anopheles arabiensis, An. quadriannulatus and four An. gambiae populations, as well as published sequences from other Culicidae, we contrasted patterns of polymorphisms between different functional units of the same gene within and between populations. Our results revealed selection signatures operating on different time scales. At the most recent time scale, within-population diversity revealed purifying selection. Between populations and between species variation revealed reduced differentiation (GNBP and gambicin at coding vs. noncoding- regions, consistent with balancing selection. McDonald-Kreitman tests between An. quadriannulatus and both sibling species revealed higher fixation rate of synonymous than nonsynonymous substitutions (GNBP in accordance with frequency dependent balancing selection. At the longest time scale (>100 my, PAML analysis using distant Culicid taxa revealed positive selection at one codon in gambicin. Patterns of genetic variation were independent of exposure to human pathogens. SIGNIFICANCE AND CONCLUSIONS: Purifying selection is the most common form of selection operating on immune genes as it was detected on a contemporary time scale on all genes. Selection for "hypervariability" was not detected, but negative balancing selection, detected at a recent evolutionary time scale

  1. The effect of dams and seasons on malaria incidence and anopheles abundance in Ethiopia

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    2013-01-01

    Background Reservoirs created by damming rivers are often believed to increase malaria incidence risk and/or stretch the period of malaria transmission. In this paper, we report the effects of a mega hydropower dam on P. falciparum malaria incidence in Ethiopia. Methods A longitudinal cohort study was conducted over a period of 2 years to determine Plasmodium falciparum malaria incidence among children less than 10 years of age living near a mega hydropower dam in Ethiopia. A total of 2080 children from 16 villages located at different distances from a hydropower dam were followed up from 2008 to 2010 using active detection of cases based on weekly house to house visits. Of this cohort of children, 951 (48.09%) were females and 1059 (51.91%) were males, with a median age of 5 years. Malaria vectors were simultaneously surveyed in all the 16 study villages. Frailty models were used to explore associations between time-to-malaria and potential risk factors, whereas, mixed-effects Poisson regression models were used to assess the effect of different covariates on anopheline abundance. Results Overall, 548 (26.86%) children experienced at least one clinical malaria episode during the follow up period with mean incidence rate of 14.26 cases/1000 child-months at risk (95% CI: 12.16 - 16.36). P. falciparum malaria incidence showed no statistically significant association with distance from the dam reservoir (p = 0.32). However, P. falciparum incidence varied significantly between seasons (p < 0.01). The malaria vector, Anopheles arabiensis, was however more abundant in villages nearer to the dam reservoir. Conclusions P. falciparum malaria incidence dynamics were more influenced by seasonal drivers than by the dam reservoir itself. The findings could have implications in timing optimal malaria control interventions and in developing an early warning system in Ethiopia. PMID:23566411

  2. The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes

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    Kweka Eliningaya J

    2011-09-01

    Full Text Available Abstract Background Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to Anopheles gambiae s.l. and Culex quinquefasciatus in both laboratory and field conditions. Methods Oviposition response evaluation in laboratory conditions was carried out in mosquito rearing cages. The oviposition substrates were located in parallel or in diagonal positions inside the cage. Urine evaluation against gravid females of An. arabiensis and Cx. quinquefasciatus was carried out at Day 1, Day 3 and Day 7. Five millilitres (mls of cow urine was added to oviposition substrate while de-chlorinated water was used as a control. In field experiments, 500 mls of cow urine was added in artificial habitats with 2500 mls of de-chlorinated water and 2 kgs of soil. The experiment was monitored for thirty consecutive days, eggs were collected daily from the habitats at 7.00 hrs. Data analysis was performed using parametric and non-parametric tests for treatments and controls while attraction of the oviposition substrate in each species was presented using Oviposition Activity Index (OAI. Results The OAI was positive with ageing of cattle urine in culicine species in both laboratory and field experiments. The OAI for anopheline species was positive with fresh urine. The OAI during the rainy season was positive for all species tested while in the dry season the OAI for culicine spp and Anopheles gambiae s.l., changed with time from positive to negative values. Based on linear model analysis, seasons and treatments had a significant effect on the number of eggs laid in habitats, even though the number of days had no effect. Conclusion Oviposition substrates treated with

  3. Sugar-fermenting yeast as an organic source of carbon dioxide to attract the malaria mosquito Anopheles gambiae

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    Spitzen Jeroen

    2010-10-01

    . However, traps baited with yeast-produced CO2 caught similar numbers of Anopheles arabiensis as traps baited with industrial CO2. Addition of human odour increased trap catches. Conclusions Yeast-produced CO2 can effectively replace industrial CO2 for sampling of An. gambiae s.s.. This will significantly reduce costs and allow sustainable mass-application of odour-baited devices for mosquito sampling in remote areas.

  4. Adaptation through chromosomal inversions in Anopheles

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    Diego eAyala

    2014-05-01

    Full Text Available Chromosomal inversions have been repeatedly involved in local adaptation in a large number of animals and plants. The ecological and behavioral plasticity of Anopheles species - human malaria vectors - is mirrored by high amounts of polymorphic inversions. The adaptive significance of chromosomal inversions has been consistently attested by strong and significant correlations between their frequencies and a number of phenotypic traits. Here, we provide an extensive literature review of the different adaptive traits associated with chromosomal inversions in the genus Anopheles. Traits having important consequences for the success of present and future vector control measures, such as insecticide resistance and behavioral changes, are discussed.

  5. Eliminating female Anopheles arabiensis by spiking blood meals with toxicants as a sex separation method in the context of the sterile insect technique

    OpenAIRE

    Yamada, Hanano; Soliban, Sharon M; Vreysen, Marc JB; Chadee, Dave D.; Gilles, Jeremie RL

    2013-01-01

    Background Ivermectin has longevity reducing effects in several insect species, including disease transmitting mosquitoes after feeding on hosts that have received ivermectin treatment. This has important implications in mosquito population control and thus the reduction of disease transmission. In addition, ivermectin could play an enormous role in mosquito control operations by its use in the female elimination process during mass-rearing, enabling the release of only sterile males in the c...

  6. Modified mosquito landing boxes dispensing transfluthrin provide effective protection against Anopheles arabiensis mosquitoes under simulated outdoor conditions in a semi-field system.

    OpenAIRE

    Andrés, Marta; Lorenz, Lena M; Mbeleya, Edgar; Moore, Sarah J.

    2015-01-01

    Abstract Background Efforts to control malaria vectors have primarily focused on scaling-up of long-lasting insecticidal nets (LLINs) and indoor residual spraying. Although highly efficient against indoor-biting and indoor-resting vectors, these interventions have lower impact on outdoor-biting mosquitoes. Innovative vector control tools are required to prevent outdoor human–mosquito contacts. In this work, the potential of spatial repellents, delivered in an active system that requires minim...

  7. Larvicidal activities of chinaberry, neem and Bacillus thuringiensis israelensis (Bti to an insecticide resistant population of Anopheles arabiensis from Tolay, Southwest Ethiopia

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    Assalif Demissew

    2016-07-01

    Conclusions: Neem, chinaberry and Bti showed potent larvicidal and pupicidal activities. However, in the area, high level of mosquito resistance to pyrethroids and dichloro-diphenyl-tricgloroethane was seen which will pose serious challenge to vector control in the future. Therefore, using integrated approach including these botanical larvicides is warranted to manage insecticide resistance.

  8. The infectivity of the entomopathogenic fungus Beauveria bassiana to insecticide-resistant and susceptible Anopheles arabiensis mosquitoes at two different temperatures

    NARCIS (Netherlands)

    Kikankie, C.K.; Brooke, B.D.; Knols, B.G.J.; Koekemoer, L.L.; Farenhorst, M.; Hunt, R.H.; Thomas, M.B.; Coetzee, M.

    2010-01-01

    BACKGROUND: Control of the major African malaria vector species continues to rely extensively on the application of residual insecticides through indoor house spraying or bed net impregnation. Insecticide resistance is undermining the sustainability of these control strategies. Alternatives to the c

  9. An analysis of diet quality, how it controls fatty acid profiles, isotope signatures and stoichiometry in the malaria mosquito Anopheles arabiensis.

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    Rebecca Hood-Nowotny

    Full Text Available BACKGROUND: Knowing the underlying mechanisms of mosquito ecology will ensure effective vector management and contribute to the overall goal of malaria control. Mosquito populations show a high degree of population plasticity in response to environmental variability. However, the principle factors controlling population size and fecundity are for the most part unknown. Larval habitat and diet play a crucial role in subsequent mosquito fitness. Developing the most competitive insects for sterile insect technique programmes requires a "production" orientated perspective, to deduce the most effective larval diet formulation; the information gained from this process offers us some insight into the mechanisms and processes taking place in natural native mosquito habitats. METHODOLOGY/PRINCIPAL FINDINGS: Fatty acid profiles and de-novo or direct assimilation pathways, of whole-individual mosquitoes reared on a range of larval diets were determined using pyrolysis gas chromatograph/mass spectrometry. We used elemental analysis and isotope ratio mass spectrometry to measure individual-whole-body carbon, nitrogen and phosphorous values and to assess the impact of dietary quality on subsequent population stoichiometry, size, quality and isotopic signature. Diet had the greatest impact on fatty acid (FA profiles of the mosquitoes, which exhibited a high degree of dietary routing, characteristic of generalist feeders. De-novo synthesis of a number of important FAs was observed. Mosquito C:N stoichiometry was fixed in the teneral stage. Dietary N content had significant influence on mosquito size, and P was shown to be a flexible pool which limited overall population size. CONCLUSIONS/SIGNIFICANCE: Direct routing of FAs was evident but there was ubiquitous de-novo synthesis suggesting mosquito larvae are competent generalist feeders capable of survival on diet with varying characteristics. It was concluded that nitrogen availability in the larval diet controlled teneral mosquito size and that teneral CN ratio is a sex- and species-specific fixed parameter. This finding has significant implications for overall mosquito competitiveness and environmental management.

  10. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

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    Bukhari, S.T.; Middelman, A.; Koenraadt, C.J.M.; Takken, W.; Knols, B.G.J.

    2010-01-01

    Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density), fungus (species

  11. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes.

  12. Genomic Dark Matter Illuminated: Anopheles Y Chromosomes.

    Science.gov (United States)

    Redmond, Seth N; Neafsey, Daniel E

    2016-08-01

    Hall et al. have strategically used long-read sequencing technology to characterize the structure and highly repetitive content of the Y chromosome in Anopheles malaria mosquitoes. Their work confirms that this important but elusive heterochromatic sex chromosome is evolving extremely rapidly and harbors a remarkably small number of genes. PMID:27263828

  13. Anopheles (Anopheles) petragnani Del Vecchio 1939-a new mosquito species for Germany.

    Science.gov (United States)

    Becker, Norbert; Pfitzner, Wolf Peter; Czajka, Christina; Kaiser, Achim; Weitzel, Thomas

    2016-07-01

    The so far known species of the Anopheles Claviger Complex, Anopheles claviger s.s. and Anopheles petragnani, can only be distinguished by partial overlapping characteristics of immature stages and by nucleotide sequence variation of the genomic ribosomal DNA (rDNA) internal transcribed spacer 2 (ITS2) region. The known distribution of An. petragnani is so far restricted to the western Mediterranean region, whereas An. claviger s.s. occurs across most of Europe, up to the Middle East and North Africa. In our study, we investigated the larval mosquito fauna in rock pools of the Murg valley (Black Forest, Germany) once a month from April to December 2015.Among other species, larvae belonging to the Anopheles Claviger Complex were found. The fourth instar larvae were morphologically identified by chaetotaxy of the head and abdomen. The results were confirmed by a multiplex PCR and additional sequencing of the amplificates.Of the 1289 collected larvae from the rock pools, seven belonged to the Anopheles Claviger Complex. Five individuals were determined morphologically as An. petragnani and two as An. claviger s.s. The associated mosquito fauna comprised of Aedes japonicus japonicus (548 individuals), Culex pipiens s.l. and Culex torrentium (493 individuals) and Culex hortensis (241 individuals).This is the first record of An. petragnani north of the Alps. Further studies will reveal whether this is an isolated population of An. petragnani and if the investigated rock pool breeding sites represent typical habitats of this species in temperate regions in Central Europe.

  14. Comparative genome and proteome analysis of Anopheles gambiae and Drosophila melanogaster.

    Science.gov (United States)

    Zdobnov, Evgeny M; von Mering, Christian; Letunic, Ivica; Torrents, David; Suyama, Mikita; Copley, Richard R; Christophides, George K; Thomasova, Dana; Holt, Robert A; Subramanian, G Mani; Mueller, Hans-Michael; Dimopoulos, George; Law, John H; Wells, Michael A; Birney, Ewan; Charlab, Rosane; Halpern, Aaron L; Kokoza, Elena; Kraft, Cheryl L; Lai, Zhongwu; Lewis, Suzanna; Louis, Christos; Barillas-Mury, Carolina; Nusskern, Deborah; Rubin, Gerald M; Salzberg, Steven L; Sutton, Granger G; Topalis, Pantelis; Wides, Ron; Wincker, Patrick; Yandell, Mark; Collins, Frank H; Ribeiro, Jose; Gelbart, William M; Kafatos, Fotis C; Bork, Peer

    2002-10-01

    Comparison of the genomes and proteomes of the two diptera Anopheles gambiae and Drosophila melanogaster, which diverged about 250 million years ago, reveals considerable similarities. However, numerous differences are also observed; some of these must reflect the selection and subsequent adaptation associated with different ecologies and life strategies. Almost half of the genes in both genomes are interpreted as orthologs and show an average sequence identity of about 56%, which is slightly lower than that observed between the orthologs of the pufferfish and human (diverged about 450 million years ago). This indicates that these two insects diverged considerably faster than vertebrates. Aligned sequences reveal that orthologous genes have retained only half of their intron/exon structure, indicating that intron gains or losses have occurred at a rate of about one per gene per 125 million years. Chromosomal arms exhibit significant remnants of homology between the two species, although only 34% of the genes colocalize in small "microsyntenic" clusters, and major interarm transfers as well as intra-arm shuffling of gene order are detected. PMID:12364792

  15. Swarming and mating activity of Anopheles gambiae mosquitoes in semi-field enclosures.

    Science.gov (United States)

    Achinko, D; Thailayil, J; Paton, D; Mireji, P O; Talesa, V; Masiga, D; Catteruccia, F

    2016-03-01

    Anopheles gambiae Giles sensu stricto (Diptera: Culicidae) is the major Afro-tropical vector of malaria. Novel strategies proposed for the elimination and eradication of this mosquito vector are based on the use of genetic approaches, such as the sterile insect technique (SIT). These approaches rely on the ability of released males to mate with wild females, and depend on the application of effective protocols to assess the swarming and mating behaviours of laboratory-reared insects prior to their release. The present study evaluated whether large semi-field enclosures can be utilized to study the ability of males from a laboratory colony to respond to natural environmental stimuli and initiate normal mating behaviour. Laboratory-reared males exhibited spatiotemporally consistent swarming behaviour within the study enclosures. Swarm initiation, peak and termination time closely tracked sunset. Comparable insemination rates were observed in females captured in copula in the semi-field cages relative to females in small laboratory cages. Oviposition rates after blood feeding were also similar to those observed in laboratory settings. The data suggest that outdoor enclosures are suitable for studying swarming and mating in laboratory-bred males in field-like settings, providing an important reference for future studies aimed at assessing the comparative mating ability of strains for SIT and other vector control strategies. PMID:26508420

  16. Food of larval Anopheles culicifacies and Anopheles varuna in a stream habitat in Sri Lanka

    DEFF Research Database (Denmark)

    Piyaratne, M K; Amerasinghe, P H; Amerasinghe, F P;

    2005-01-01

    No previous studies have been conducted on the natural food of larval Anopheles culicifacies s.l. (the major malaria vector) and An. varuna (a secondary vector) in Sri Lanka. The present study analyzed the contents of guts dissected from larvae collected from pools in a natural stream-cum-irrigat...

  17. Biting behavior of Anopheles mosquitoes in Costa Marques, Rondonia, Brazil

    Directory of Open Access Journals (Sweden)

    Terry A. Klein

    1991-03-01

    Full Text Available Mosquito collections were made in and near Costa Marques, Rondonia, Brazil, to determine anopheline anthropophilic/zoophilic behavior. Collections from a non-illuminated, bovine-baited trap and indoor and outdoor human-bait collections were compared. Anopheles darlingi and Anopheles deaneorum were more anthropophilic than the other anophelines collected. The remainder of the Anopheles species were collected much morefrequently in bovine-baited traps than in human-bait collections. Anopheles darlingi and An. deaneorum were more frequently collected inside houses than the other anopheline species. But, when collections were made in a house with numerous openings in the walls, there were few differences in the percentages of each species biting man indoors versus outdoors. Anopheles darlingi was the predominant mosquito collected, both inside and outside houses, and had the strongest anthropophilic feeding behavior of the anophelines present.Para determinar o comportamento antropofilico e zoofilico dos anofelinos, foram capturados mosquitos na periferia e na zona urbana de Costa Marques, Rondônia, Brasil. Foram comparadas as capturas feitas à noite, com iscas bovinas e humanas, dentro efora de casa. O Anopheles darlingi e o Anopheles deaneorumforam mais antropojilicos do que os outros anofelinos capturados. O restante das espécies anofelinas foi capturado mais freqüentemente nas iscas bovinas do que nas humanas. Anopheles darlingi e Anopheles deaneorumforam capturados dentro de casa com mais freqüência do que as outras espécies anofelinas. Porém, quando a captura foi feita em casas com muitas aberturas nas paredes houve pouca diferença nas porcentagens de cada espécie sugadora de humanos dentro efora de casa. Anopheles darlingi foi o mosquito capturado com mais freqüência, dentro e fora de casa, e apresentava maior antropofilia em relação aos outros anofelinos presentes.

  18. Humoral response to the Anopheles gambiae salivary protein gSG6: a serological indicator of exposure to Afrotropical malaria vectors.

    Directory of Open Access Journals (Sweden)

    Cinzia Rizzo

    Full Text Available Salivary proteins injected by blood feeding arthropods into their hosts evoke a saliva-specific humoral response which can be useful to evaluate exposure to bites of disease vectors. However, saliva of hematophagous arthropods is a complex cocktail of bioactive factors and its use in immunoassays can be misleading because of potential cross-reactivity to other antigens. Toward the development of a serological marker of exposure to Afrotropical malaria vectors we expressed the Anopheles gambiae gSG6, a small anopheline-specific salivary protein, and we measured the anti-gSG6 IgG response in individuals from a malaria hyperendemic area of Burkina Faso, West Africa. The gSG6 protein was immunogenic and anti-gSG6 IgG levels and/or prevalence increased in exposed individuals during the malaria transmission/rainy season. Moreover, this response dropped during the intervening low transmission/dry season, suggesting it is sensitive enough to detect variation in vector density. Members of the Fulani ethnic group showed higher anti-gSG6 IgG response as compared to Mossi, a result consistent with the stronger immune reactivity reported in this group. Remarkably, anti-gSG6 IgG levels among responders were high in children and gradually declined with age. This unusual pattern, opposite to the one observed with Plasmodium antigens, is compatible with a progressive desensitization to mosquito saliva and may be linked to the continued exposure to bites of anopheline mosquitoes. Overall, the humoral anti-gSG6 IgG response appears a reliable serological indicator of exposure to bites of the main African malaria vectors (An. gambiae, Anopheles arabiensis and, possibly, Anopheles funestus and it may be exploited for malaria epidemiological studies, development of risk maps and evaluation of anti-vector measures. In addition, the gSG6 protein may represent a powerful model system to get a deeper understanding of molecular and cellular mechanisms underlying the

  19. Insecticide resistance in Anopheles gambiae: data from the first year of a multi-country study highlight the extent of the problem

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    Sagnon N'Falé

    2009-12-01

    Full Text Available Abstract Background Insecticide resistance in malaria vectors is a growing concern in many countries which requires immediate attention because of the limited chemical arsenal available for vector control. The current extent and distribution of this resistance in many parts of the continent is unknown and yet such information is essential for the planning of effective malaria control interventions. Methods In 2008, a network was established, with financial support from WHO/TDR, to investigate the extent of insecticide resistance in malaria vectors in five African countries. Here, the results of bioassays on Anopheles gambiae sensu lato from two rounds of monitoring from 12 sentinel sites in three of the partner countries are reported. Results Resistance is very heterogeneous even over relatively small distances. Furthermore, in some sites, large differences in mortality rates were observed during the course of the malaria transmission season. Using WHO diagnostic doses, all populations from Burkina Faso and Chad and two of the four populations from Sudan were classified as resistant to permethrin and/or deltamethrin. Very high frequencies of DDT resistance were found in urban areas in Burkina Faso and Sudan and in a cotton-growing district in Chad. In areas where both An. gambiae s.s. and Anopheles arabiensis were present, resistance was found in both species, although generally at a higher frequency in An gambiae s.s. Anopheles gambiae s.l. remains largely susceptible to the organophosphate fenitrothion and the carbamate bendiocarb in the majority of the sentinel sites with the exception of two sites in Burkina Faso. In the cotton-growing region of Soumousso in Burkina Faso, the vector population is resistant to all four classes of insecticide available for malaria control. Conclusions Possible factors influencing the frequency of resistant individuals observed in the sentinel sites are discussed. The results of this study highlight the

  20. Composição da fauna de Anopheles (Díptera : Culicidae) da reserva indígena do Ocoy

    OpenAIRE

    Araujo, Roderlei de

    2012-01-01

    Resumo: A malária no Estado do Paraná deve-se principalmente ao fluxo de pessoas advindas de áreas endêmicas de outras regiões do país, e a manutenção do vetor transmissor em algumas regiões do estado onde, o risco para ocorrência de casos autóctones da doença inspira cuidado. O presente estudo teve por objetivo descrever a composição da fauna de Anopheles (Diptera: Culicidae) da Reserva Indígena do Ocoy, foco ativo de malária no município de São Miguel do Iguaçu. As análises foram feitas atr...

  1. Neuropeptides and Peptide Hormones in Anopheles gambiae

    Science.gov (United States)

    Riehle, Michael A.; Garczynski, Stephen F.; Crim, Joe W.; Hill, Catherine A.; Brown, Mark R.

    2002-10-01

    The African malaria mosquito, Anopheles gambiae, is specialized for rapid completion of development and reproduction. A vertebrate blood meal is required for egg production, and multiple feedings subsequently allow transmission of malaria parasites, Plasmodium spp. Regulatory peptides from 35 genes annotated from the A. gambiae genome likely coordinate these and other physiological processes. Plasmodium parasites may affect actions of newly identified insulin-like peptides, which coordinate growth and reproduction of its vector, A. gambiae, as in Drosophila melanogaster, Caenorhabditis elegans, and mammals. This genomic information provides a basis to expand understanding of hematophagy and pathogen transmission in this mosquito.

  2. Effect of Novaluron (Rimon 10 EC) on the mosquitoes Anopheles albimanus, Anopheles pseudopunctipennis, Aedes aegypti, Aedes albopictus and Culex quinquefasciatus from Chiapas, Mexico.

    Science.gov (United States)

    Arredondo-Jiménez, J I; Valdez-Delgado, K M

    2006-12-01

    Dengue fever is a serious problem in Mexico and vector control has not been effective enough at preventing outbreaks. Malaria is largely under control, but it is important that new control measures continue to be developed. Novaluron, a novel host-specific insect growth regulator and chitin synthesis inhibitor, has proved to be effective against agricultural pests, but its efficacy against larval mosquito vectors under field conditions remains unknown. In accordance with the World Health Organization Pesticide Evaluation Scheme, phase I, II and III studies were conducted to evaluate the efficacy and residual effect of Novaluron (Rimon 10 EC, Makhteshim, Beer-Sheva, Israel) on the malaria vectors Anopheles albimanus Wiedemann (Diptera: Culicidae) and Anopheles pseudopunctipennis Theobald, the dengue vectors Aedes aegypti (L) and Aedes albopictus Skuse and the nuisance mosquito Culex quinquefasciatus Say. Laboratory susceptibility tests yielded diagnostic concentrations for all five target species. Field trials to identify the optimum field dosage of Novaluron against Anopheles mosquitoes were carried out under semi-natural conditions in artificial plots and in vessels with wild mosquitoes. Efficacy was measured by monitoring mortality of larvae and pupae and the percentage of inhibition of emergence from floating cages. Dosages of Novaluron for field tests were based on pupal LC(99) (lethal concentration 99%) of An. pseudopunctipennis (0.166 mg/L) in plots and average pupal LC(99) of Ae. aegypti and Ae. albopictus (0.55 mg/L). At all dosages tested, Novaluron significantly reduced larval populations of An. albimanus, Culex coronator Dyar & Knab, Ae. albopictus and Cx. quinquefasciatus by approximately 90%, inhibited adult emergence of An. albimanus and An. pseudopunctipennis by approximately 97% for almost 4 months in experimental plots, and inhibited adult emergence of Ae. aegypti and Ae. albopictus by approximately 97% for up to 14 weeks. Recommended dosages of

  3. Factors affecting fungus-induced larval mortality in Anopheles gambiae and Anopheles stephensi

    Directory of Open Access Journals (Sweden)

    Takken Willem

    2010-01-01

    Full Text Available Abstract Background Entomopathogenic fungi have shown great potential for the control of adult malaria vectors. However, their ability to control aquatic stages of anopheline vectors remains largely unexplored. Therefore, how larval characteristics (Anopheles species, age and larval density, fungus (species and concentration and environmental effects (exposure duration and food availability influence larval mortality caused by fungus, was studied. Methods Laboratory bioassays were performed on the larval stages of Anopheles gambiae and Anopheles stephensi with spores of two fungus species, Metarhizium anisopliae and Beauveria bassiana. For various larval and fungal characteristics and environmental effects the time to death was determined and survival curves established. These curves were compared by Kaplan Meier and Cox regression analyses. Results Beauveria bassiana and Metarhizium anisopliae caused high mortality of An. gambiae and An. stephensi larvae. However, Beauveria bassiana was less effective (Hazard ratio (HR Metarhizium anisopliae. Anopheles stephensi and An. gambiae were equally susceptible to each fungus. Older larvae were less likely to die than young larvae (HR Conclusions This study shows that both fungus species have potential to kill mosquitoes in the larval stage, and that mortality rate depends on fungus species itself, larval stage targeted, larval density and amount of nutrients available to the larvae. Increasing the concentration of fungal spores or reducing the exposure time to spores did not show a proportional increase and decrease in mortality rate, respectively, because the spores clumped together. As a result spores did not provide uniform coverage over space and time. It is, therefore, necessary to develop a formulation that allows the spores to spread over the water surface. Apart from formulation appropriate delivery methods are also necessary to avoid exposing non-target organisms to fungus.

  4. Larvicidal and repellent potential of Moringa oleifera against malarial vector, Anopheles stephensi Liston (Insecta: Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    K Prabhu

    2011-04-01

    Conclusions: The present study indicates that the phytochemicals derived from M. oleifera seeds extracts are effective mosquito vector control agents and the plant extracts may be used for further integrated pest management programs.

  5. A comprehensive gene expression atlas of sex- and tissue-specificity in the malaria vector, Anopheles gambiae

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    Crisanti Andrea

    2011-06-01

    Full Text Available Abstract Background The mosquito, Anopheles gambiae, is the primary vector of human malaria, a disease responsible for millions of deaths each year. To improve strategies for controlling transmission of the causative parasite, Plasmodium falciparum, we require a thorough understanding of the developmental mechanisms, physiological processes and evolutionary pressures affecting life-history traits in the mosquito. Identifying genes expressed in particular tissues or involved in specific biological processes is an essential part of this process. Results In this study, we present transcription profiles for ~82% of annotated Anopheles genes in dissected adult male and female tissues. The sensitivity afforded by examining dissected tissues found gene activity in an additional 20% of the genome that is undetected when using whole-animal samples. The somatic and reproductive tissues we examined each displayed patterns of sexually dimorphic and tissue-specific expression. By comparing expression profiles with Drosophila melanogaster we also assessed which genes are well conserved within the Diptera versus those that are more recently evolved. Conclusions Our expression atlas and associated publicly available database, the MozAtlas (http://www.tissue-atlas.org, provides information on the relative strength and specificity of gene expression in several somatic and reproductive tissues, isolated from a single strain grown under uniform conditions. The data will serve as a reference for other mosquito researchers by providing a simple method for identifying where genes are expressed in the adult, however, in addition our resource will also provide insights into the evolutionary diversity associated with gene expression levels among species.

  6. A Physical Map for an Asian Malaria Mosquito, Anopheles stephensi

    OpenAIRE

    Maria V Sharakhova; Xia, Ai; Tu, Zhijian; Shouche, Yogesh S.; Unger, Maria F; Sharakhov, Igor V

    2010-01-01

    Physical mapping is a useful approach for studying genome organization and evolution as well as for genome sequence assembly. The availability of polytene chromosomes in malaria mosquitoes provides a unique opportunity to develop high-resolution physical maps. We report a 0.6-Mb-resolution physical map consisting of 422 DNA markers hybridized to 379 chromosomal sites of the Anopheles stephensi polytene chromosomes. This makes An. stephensi second only to Anopheles gambiae in density of a phys...

  7. DDT-resistance in Anopheles stephensi.

    Science.gov (United States)

    DAVIDSON, G; JACKSON, C E

    1961-01-01

    In view of the increasing number of reports from different parts of the world indicating resistance to DDT in both adults and larvae of Anopheles stephensi, an important malaria vector, a series of laboratory studies has been carried out on the degree, the pattern and the mode of inheritance of resistance in this species. A DDT-resistant strain from Iraq and a susceptible strain from India were used.In four sets of observations made in the course of tests on both adults and larvae a monofactorial type of inheritance was indicated, and the factor involved was shown to be dependent for its expression on the genetic background.DDT-resistance in A. stephensi appears to be similar in most respects to that in A. sundaicus. PMID:13883789

  8. Larvicidal activity of medicinal plant extracts against Anopheles subpictus & Culex tritaeniorhynchus

    Science.gov (United States)

    Kamaraj, C.; Bagavan, A.; Elango, G.; Zahir, A. Abduz; Rajakumar, G.; Marimuthu, S.; Santhoshkumar, T.; Rahuman, A. Abdul

    2011-01-01

    Background & objectives: Mosquitoes transmit serious human diseases, causing millions of deaths every year and the development of resistance to chemical insecticides resulting in rebounding vectorial capacity. Plants may be alternative sources of mosquito control agents. The present study assessed the role of larvicidal activities of hexane, chloroform, ethyl acetate, acetone, and methanol dried leaf and bark extracts of Annona squamosa L., Chrysanthemum indicum L., and Tridax procumbens L. against the fourth instar larvae of malaria vector, Anopheles subpictus Grassi and Japanese encephalitis vector, Culex tritaeniorhynchus Giles (Diptera: Culicidae). Methods: Larvicidal activities of three medicinal plant extracts were studied in the range of 4.69 to 1000 mg/l in the laboratory bioassays against early 4th instar larvae of An. subpictus and Cx. tritaeniorhynchus. The mortality data were subjected to probit analysis to determine the lethal concentrations (LC50 and LC90) to kill 50 and 90 per cent of the treated larvae of the respective species. Results: All plant extracts showed moderate effects after 24 h of exposure; however, the highest toxic effect of bark methanol extract of A. squamosa, leaf ethyl acetate extract of C. indicum and leaf acetone extract of T. procumbens against the larvae of An. subpictus (LC50 = 93.80, 39.98 and 51.57 mg/l) and bark methanol extract of A. squamosa, leaf methanol extract of C. indicum and leaf ethyl acetate extract of T. procumbens against the larvae of Cx. tritaeniorhynchus (LC50 =104.94, 42.29 and 69.16 mg/l) respectively. Interpretation & Conclusions: Our data suggest that the bark ethyl acetate and methanol extract of A. squamosa, leaf ethyl acetate and methanol extract of C. indicum, acetone and ethyl acetate extract of T. procumbens have the potential to be used as an ecofriendly approach for the control of the An. subpictus, and Cx. tritaeniorhynchus. PMID:21808141

  9. Physiology and development of the M and S molecular forms of Anopheles gambiae in Burkina Faso (West Africa).

    Science.gov (United States)

    Mouline, K; Mamai, W; Agnew, P; Tchonfienet, M; Brengues, C; Dabire, R; Robert, V; Simard, F

    2012-12-01

    In West Africa, M and S molecular forms of Anopheles gambiae sensu stricto (Diptera: Culicidae) Giles, frequently occur together, although with different population bionomics. The S form typically breeds in rain-dependant water collections and is present during the rainy season only whereas the M form can thrive all year long in areas with permanent breeding opportunities. In the present study, we explored physiological and developmental trade-offs at play in laboratory colonies and field populations of the M and S forms that originated from an area of sympatry in Burkina Faso, where M and S larvae exhibit such habitat segregation. In the laboratory, larvae of the M form developed slower than the S form (mean values 9.51 and 8.85 days, respectively, Wilcoxon's test, P < 0.001). Although wing length and dry weight at emergence showed large variations, M females were on average 8% heavier than S females of similar wing length. Higher nutritional reserves (proteins and lipids) in teneral adults explained part of this weight difference, reflecting a better ability of the M form to garner resources at the larval stage. Furthermore, a higher rate of ovarian maturation was observed in the M form after a single bloodmeal. The relevance of these findings for parasite transmission is discussed. PMID:22681446

  10. Dicty_cDB: Contig-U11312-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available KL188_... 59 1e-06 FJ864200_1( FJ864200 |pid:none) Anopheles arabiensis isolate FZ17_... 57 2e-06 FJ864169_... FJ864199 |pid:none) Anopheles arabiensis isolate FZ14_... 57 2e-06 FJ864173_1( FJ864173 |pid:none) Anopheles arabie

  11. Successful field trial of attractive toxic sugar bait (ATSB plant-spraying methods against malaria vectors in the Anopheles gambiae complex in Mali, West Africa

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    Doumbia Seydou

    2010-07-01

    Full Text Available Abstract Background Based on highly successful demonstrations in Israel that attractive toxic sugar bait (ATSB methods can decimate local populations of mosquitoes, this study determined the effectiveness of ATSB methods for malaria vector control in the semi-arid Bandiagara District of Mali, West Africa. Methods Control and treatment sites, selected along a road that connects villages, contained man-made ponds that were the primary larval habitats of Anopheles gambiae and Anopheles arabiensis. Guava and honey melons, two local fruits shown to be attractive to An. gambiae s.l., were used to prepare solutions of Attractive Sugar Bait (ASB and ATSB that additionally contained boric acid as an oral insecticide. Both included a color dye marker to facilitate determination of mosquitoes feeding on the solutions. The trial was conducted over a 38-day period, using CDC light traps to monitor mosquito populations. On day 8, ASB solution in the control site and ATSB solution in the treatment site were sprayed using a hand-pump on patches of vegetation. Samples of female mosquitoes were age-graded to determine the impact of ATSB treatment on vector longevity. Results Immediately after spraying ATSB in the treatment site, the relative abundance of female and male An. gambiae s.l. declined about 90% from pre-treatment levels and remained low. In the treatment site, most females remaining after ATSB treatment had not completed a single gonotrophic cycle, and only 6% had completed three or more gonotrophic cycles compared with 37% pre-treatment. In the control site sprayed with ASB (without toxin, the proportion of females completing three or more gonotrophic cycles increased from 28.5% pre-treatment to 47.5% post-treatment. In the control site, detection of dye marker in over half of the females and males provided direct evidence that the mosquitoes were feeding on the sprayed solutions. Conclusion This study in Mali shows that even a single application of

  12. Tabanomorpha, Asilomorpha and associated families (Diptera)

    OpenAIRE

    Jere Kahanpää; Kaj Winqvist; Theo Zeegers

    2014-01-01

    Abstract A checklist of the ‘lower Brachycera ’ of Finland is presented. This part of the complete checklist of Finnish Diptera covers the families Acroceridae , Asilidae , Athericidae , Bombyliidae , Mythicomyiidae , Rhagionidae , Scenopinidae , Stratiomyidae , Tabanidae , Therevidae , Xylomyidae and Xylophagidae .

  13. Metabolic pathways in Anopheles stephensi mitochondria.

    Science.gov (United States)

    Giulivi, Cecilia; Ross-Inta, Catherine; Horton, Ashley A; Luckhart, Shirley

    2008-10-15

    No studies have been performed on the mitochondria of malaria vector mosquitoes. This information would be valuable in understanding mosquito aging and detoxification of insecticides, two parameters that have a significant impact on malaria parasite transmission in endemic regions. In the present study, we report the analyses of respiration and oxidative phosphorylation in mitochondria of cultured cells [ASE (Anopheles stephensi Mos. 43) cell line] from A. stephensi, a major vector of malaria in India, South-East Asia and parts of the Middle East. ASE cell mitochondria share many features in common with mammalian muscle mitochondria, despite the fact that these cells are of larval origin. However, two major differences with mammalian mitochondria were apparent. One, the glycerol-phosphate shuttle plays as major a role in NADH oxidation in ASE cell mitochondria as it does in insect muscle mitochondria. In contrast, mammalian white muscle mitochondria depend primarily on lactate dehydrogenase, whereas red muscle mitochondria depend on the malate-oxaloacetate shuttle. Two, ASE mitochondria were able to oxidize proline at a rate comparable with that of alpha-glycerophosphate. However, the proline pathway appeared to differ from the currently accepted pathway, in that oxoglutarate could be catabolized completely by the tricarboxylic acid cycle or via transamination, depending on the ATP need.

  14. Mermithid nematodes found in adult Anopheles from southeastern Senegal

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    Kobylinski Kevin C

    2012-06-01

    Full Text Available Abstract Background Over two dozen mermithid nematodes have been described parasitizing mosquitoes worldwide, however, only two species were found in Africa. Mermithid nematodes kill their mosquito host upon emergence, which suggests that they could be developed as biological control agents of mosquitoes. Both Romanomermis culicivorax and Romanomermis iyengari have been reared for mass release to control numerous Anopheles species vector populations, and in one instance this may have led to reduced malaria prevalence in a human population. Methods Anopheles mosquitoes were collected during a malaria study in southeastern Senegal. Two different adult blood fed mosquitoes had a single mermithid nematode emerge from their anus while they were being held post-capture. Primers from the 18 S rDNA were developed to sequence nematode DNA and screen mosquitoes for mermithid DNA. 18 S rDNA from the Senegalese mermithid and other mermithid entries in GenBank were used to create a Maximum Parsimony tree of the Mermithidae family. Results The mermithid was present in 1.8% (10/551 of the sampled adult Anopheles species in our study area. The mermithid was found in An. gambiae s.s., An. funestus, and An. rufipes from the villages of Ndebou, Boundoucondi, and Damboucoye. Maximum parsimony analysis confirmed that the nematode parasites found in Anopheles were indeed mermithid parasites, and of the mermithid sequences available in GenBank, they are most closely related to Strelkovimermis spiculatus. Conclusions To our knowledge, this is the first report of mermithids from adult Anopheles mosquitoes in Senegal. The mermithid appears to infect Anopheles mosquitoes that develop in diverse larval habitats. Although maximum parsimony analysis determined the mermithid was closely related to Strelkovimermis spiculatus, several characteristics of the mermithid were more similar to the Empidomermis genus. Future mermithid isolations will hopefully allow: formal

  15. Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Mário Luís Pessôa Guedes

    2014-03-01

    Full Text Available Mosquito community composition in dynamic landscapes from the Atlantic Forest biome (Diptera, Culicidae. Considering that some species of Culicidae are vectors of pathogens, both the knowledge of the diversity of the mosquito fauna and how some environment factors influence in it, are important subjects. In order to address the composition of Culicidae species in a forest reserve in southern Atlantic Forest, we compared biotic and abiotic environmental determinants and how they were associated with the occurrence of species between sunset and sunrise. The level of conservation of the area was also considered. The investigation was carried out at Reserva Natural do Morro da Mina, in Antonina, state of Paraná, Brazil. We performed sixteen mosquito collections employing Shannon traps at three-hour intervals, from July 2008 to June 2009. The characterization of the area was determined using ecological indices of diversity, evenness, dominance and similarity. We compared the frequency of specimens with abiotic variables, i.e., temperature, relative humidity and pluviosity. Seven thousand four hundred ten mosquito females were captured. They belong to 48 species of 12 genera. The most abundant genera were Anopheles, Culex, Coquillettidia, Aedes and Runchomyia. Among the species, the most abundant was Anopheles cruzii, the primary vector of Plasmodium spp. in the Atlantic Forest. Results of the analyses showed that the abiotic variables we tested did not influence the occurrence of species, although certain values suggested that there was an optimum range for the occurrence of culicid species. It was possible to detect the presence of species of Culicidae with different epidemiologic profiles and habitat preference.

  16. Biology & control of Anopheles culicifacies Giles 1901.

    Science.gov (United States)

    Sharma, V P; Dev, V

    2015-05-01

    Malaria epidemiology is complex due to multiplicity of disease vectors, sibling species complex and variations in bionomical characteristics, vast varied terrain, various ecological determinants. There are six major mosquito vector taxa in India, viz. Anopheles culicifacies, An. fluviatilis, An. stephensi, An. minimus, An. dirus and An. sundaicus. Among these, An. culicifacies is widely distributed and considered the most important vector throughout the plains and forests of India for generating bulk of malaria cases (>60% annually). Major malaria epidemics are caused by An. culicifaices. It is also the vector of tribal malaria except parts of Odisha and Northeastern States of India. An. culicifacies has been the cause of perennial malaria transmission in forests, and over the years penetrated the deforested areas of Northeast. An. culicifacies participates in malaria transmission either alone or along with An. stephensi or An. fluviatilis. The National Vector Borne Disease Control Programme (NVBDCP) spends about 80 per cent malaria control budget annually in the control of An. culicifacies, yet it remains one of the most formidable challenges in India. With recent advances in molecular biology there has been a significant added knowledge in understanding the biology, ecology, genetics and response to interventions, requiring stratification for cost-effective and sustainable malaria control. Research leading to newer interventions that are evidence-based, community oriented and sustainable would be useful in tackling the emerging challenges in malaria control. Current priority areas of research should include in-depth vector biology and control in problem pockets, preparation of malaria-risk maps for focused and selective interventions, monitoring insecticide resistance, cross-border initiative and data sharing, and coordinated control efforts for achieving transmission reduction, and control of drug-resistant malaria. The present review on An. culicifacies

  17. Dicty_cDB: Contig-U09475-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available 81_1( FJ653781 |pid:none) Anopheles gambiae isolate GA5011 G... 47 4e-04 FJ653825_1( FJ653825 |pid:none) Anopheles arabie...20 |pid:none) Anopheles arabiensis isolate AA501... 47 5e-04 FJ653824_1( FJ653824 |pid:none) Anopheles arabie...nsis isolate AA502... 47 5e-04 FJ653826_1( FJ653826 |pid:none) Anopheles arabiensis isolate AA503... 47 5e-...04 FJ653819_1( FJ653819 |pid:none) Anopheles arabiensis isolate AA500... 47 5e-04... FJ653823_1( FJ653823 |pid:none) Anopheles arabiensis isolate AA502... 47 5e-04 CU928175_540( CU928175 |pid:

  18. Temperature influence on embryonic development of Anopheles albitarsis and Anopheles aquasalis

    Directory of Open Access Journals (Sweden)

    Sabrina Cardozo Gonçalvez de Carvalho

    2002-12-01

    Full Text Available Temperature influence on the embryonic development of Anopheles aquasalis and An. albitarsis was investigated. At 26ºC, 75% and 60% of respectively An. aquasalis and An. albitarsis eggs hatched, with one peak of eclosion, between the 2nd and 3rd day after oviposition. At 20 ± 2ºC, around 66-70% of An. aquasalis eggs hatched, with one eclosion peak, on the 5th day. On the other hand, An. albitarsis eclosion at 21 ± 2ºC decreased to 10-22%, with two eclosion peaks, on the 4th-5th day and on the 9th-12th day. These data indicate a stronger temperature influence over An.albitarsis than over An. aquasalis embryos.

  19. Ecology of Anopheles spp. in Central Lombok Regency

    Directory of Open Access Journals (Sweden)

    Majematang Mading

    2014-06-01

    Full Text Available Malaria remains a public health problem in West Nusa Tenggara Province. Central Lombok District is one of the areas with high case of malaria. Annual Malaria Incidence (AMI was increased from 5.9 ‰ in 2006, 6.7‰ up to 8.1‰ in 2008. The objective of the study is to describe the ecological condition of Anopheles spp. through observation, measurement of environmental variables, larvae and adult collection. This research was an observational research with cross-sectional study. The population of this study is all mosquitos and breeding habitats of Anopheles spp. that exist in the research location. Ecological observations carried out on anopheles breeding habitats including acidity, salinity, shaded places and aquatic biota. Air temperature and humidity measured at the adult mosquitoes trapping sites. The result showed that pH values of water is around 9.00, salinity in the breeding habitats around 14 ppm, and water biota (i.e. moss, grass, shrimps, fishes, tadpoles and crabs surrounded by bushes with larvae density 0,1-28,8 each dipping. The air measurement at the time was between 23°-27° Celsius and 65%-84% humidity. This research concludes that ecology and environmental conditions were supporting the development of larvae and adult mosquito of Anopheles spp.

  20. The evolution of the Anopheles 16 genomes project

    NARCIS (Netherlands)

    Neafsey, Daniel E.; Christophides, George K.; Collins, Frank H.; Emrich, Scott J.; Fontaine, Michael C.; Gelbart, William; Hahn, Matthew W.; Howell, Paul I.; Kafatos, Fotis C.; Lawson, Daniel; Muskavitch, Marc A. T.; Waterhouse, Robert M.; Williams, Louise J.; Besansky, Nora J.

    2013-01-01

    We report the imminent completion of a set of reference genome assemblies for 16 species of Anopheles mosquitoes. In addition to providing a generally useful resource for comparative genomic analyses, these genome sequences will greatly facilitate exploration of the capacity exhibited by some Anophe

  1. Urban agriculture and Anopheles habitats in Dar es Salaam, Tanzania.

    Science.gov (United States)

    Dongus, Stefan; Nyika, Dickson; Kannady, Khadija; Mtasiwa, Deo; Mshinda, Hassan; Gosoniu, Laura; Drescher, Axel W; Fillinger, Ulrike; Tanner, Marcel; Killeen, Gerry F; Castro, Marcia C

    2009-05-01

    A cross-sectional survey of agricultural areas, combined with routinely monitored mosquito larval information, was conducted in urban Dar es Salaam, Tanzania, to investigate how agricultural and geographical features may influence the presence of Anopheles larvae. Data were integrated into a geographical information systems framework, and predictors of the presence of Anopheles larvae in farming areas were assessed using multivariate logistic regression with independent random effects. It was found that more than 5% of the study area (total size 16.8 km2) was used for farming in backyard gardens and larger open spaces. The proportion of habitats containing Anopheles larvae was 1.7 times higher in agricultural areas compared to other areas (95% confidence interval = 1.56-1.92). Significant geographic predictors of the presence of Anopheles larvae in gardens included location in lowland areas, proximity to river, and relatively impermeable soils. Agriculture-related predictors comprised specific seedbed types, mid-sized gardens, irrigation by wells, as well as cultivation of sugar cane or leafy vegetables. Negative predictors included small garden size, irrigation by tap water, rainfed production and cultivation of leguminous crops or fruit trees. Although there was an increased chance of finding Anopheles larvae in agricultural sites, it was found that breeding sites originated by urban agriculture account for less than a fifth of all breeding sites of malaria vectors in Dar es Salaam. It is suggested that strategies comprising an integrated malaria control effort in malaria-endemic African cities include participatory involvement of farmers by planting shade trees near larval habitats.

  2. Urban agriculture and Anopheles habitats in Dar es Salaam, Tanzania

    Directory of Open Access Journals (Sweden)

    Stefan Dongus

    2009-05-01

    Full Text Available A cross-sectional survey of agricultural areas, combined with routinely monitored mosquito larval information, was conducted in urban Dar es Salaam, Tanzania, to investigate how agricultural and geographical features may influence the presence of Anopheles larvae. Data were integrated into a geographical information systems framework, and predictors of the presence of Anopheles larvae in farming areas were assessed using multivariate logistic regression with independent random effects. It was found that more than 5% of the study area (total size 16.8 km2 was used for farming in backyard gardens and larger open spaces. The proportion of habitats containing Anopheles larvae was 1.7 times higher in agricultural areas compared to other areas (95% confidence interval = 1.56-1.92. Significant geographic predictors of the presence of Anopheles larvae in gardens included location in lowland areas, proximity to river, and relatively impermeable soils. Agriculture-related predictors comprised specific seedbed types, mid-sized gardens, irrigation by wells, as well as cultivation of sugar cane or leafy vegetables. Negative predictors included small garden size, irrigation by tap water, rainfed production and cultivation of leguminous crops or fruit trees. Although there was an increased chance of finding Anopheles larvae in agricultural sites, it was found that breeding sites originated by urban agriculture account for less than a fifth of all breeding sites of malaria vectors in Dar es Salaam. It is suggested that strategies comprising an integrated malaria control effort in malaria-endemic African cities include participatory involvement of farmers by planting shade trees near larval habitats.

  3. Unravelling the Evolution of the Allatostatin-Type A, KISS and Galanin Peptide-Receptor Gene Families in Bilaterians: Insights from Anopheles Mosquitoes.

    Directory of Open Access Journals (Sweden)

    Rute C Felix

    Full Text Available Allatostatin type A receptors (AST-ARs are a group of G-protein coupled receptors activated by members of the FGL-amide (AST-A peptide family that inhibit food intake and development in arthropods. Despite their physiological importance the evolution of the AST-A system is poorly described and relatively few receptors have been isolated and functionally characterised in insects. The present study provides a comprehensive analysis of the origin and comparative evolution of the AST-A system. To determine how evolution and feeding modified the function of AST-AR the duplicate receptors in Anopheles mosquitoes, were characterised. Phylogeny and gene synteny suggested that invertebrate AST-A receptors and peptide genes shared a common evolutionary origin with KISS/GAL receptors and ligands. AST-ARs and KISSR emerged from a common gene ancestor after the divergence of GALRs in the bilaterian genome. In arthropods, the AST-A system evolved through lineage-specific events and the maintenance of two receptors in the flies and mosquitoes (Diptera was the result of a gene duplication event. Speciation of Anopheles mosquitoes affected receptor gene organisation and characterisation of AST-AR duplicates (GPRALS1 and 2 revealed that in common with other insects, the mosquito receptors were activated by insect AST-A peptides and the iCa2+-signalling pathway was stimulated. GPRALS1 and 2 were expressed mainly in mosquito midgut and ovaries and transcript abundance of both receptors was modified by feeding. A blood meal strongly up-regulated expression of both GPRALS in the midgut (p < 0.05 compared to glucose fed females. Based on the results we hypothesise that the AST-A system in insects shared a common origin with the vertebrate KISS system and may also share a common function as an integrator of metabolism and reproduction.AST-A and KISS/GAL receptors and ligands shared common ancestry prior to the protostome-deuterostome divergence. Phylogeny and gene

  4. Genomic islands of speciation in Anopheles gambiae.

    Directory of Open Access Journals (Sweden)

    2005-09-01

    Full Text Available The African malaria mosquito, Anopheles gambiae sensu stricto (A. gambiae, provides a unique opportunity to study the evolution of reproductive isolation because it is divided into two sympatric, partially isolated subtaxa known as M form and S form. With the annotated genome of this species now available, high-throughput techniques can be applied to locate and characterize the genomic regions contributing to reproductive isolation. In order to quantify patterns of differentiation within A. gambiae, we hybridized population samples of genomic DNA from each form to Affymetrix GeneChip microarrays. We found that three regions, together encompassing less than 2.8 Mb, are the only locations where the M and S forms are significantly differentiated. Two of these regions are adjacent to centromeres, on Chromosomes 2L and X, and contain 50 and 12 predicted genes, respectively. Sequenced loci in these regions contain fixed differences between forms and no shared polymorphisms, while no fixed differences were found at nearby control loci. The third region, on Chromosome 2R, contains only five predicted genes; fixed differences in this region were also verified by direct sequencing. These "speciation islands" remain differentiated despite considerable gene flow, and are therefore expected to contain the genes responsible for reproductive isolation. Much effort has recently been applied to locating the genes and genetic changes responsible for reproductive isolation between species. Though much can be inferred about speciation by studying taxa that have diverged for millions of years, studying differentiation between taxa that are in the early stages of isolation will lead to a clearer view of the number and size of regions involved in the genetics of speciation. Despite appreciable levels of gene flow between the M and S forms of A. gambiae, we were able to isolate three small regions of differentiation where genes responsible for ecological and behavioral

  5. The fine-scale genetic structure of the malaria vectors Anopheles funestus and Anopheles gambiae (Diptera: Culicidae) in the north-eastern part of Tanzania

    NARCIS (Netherlands)

    Gélin, P.; Magalon, H.; Drakeley, C.; Maxwell, C.; Magesa, S.; Takken, W.; Boëte, C.

    2016-01-01

    Understanding the impact of altitude and ecological heterogeneity at a fine scale on the populations of malaria vectors is essential to better understand and anticipate eventual epidemiological changes. It could help to evaluate the spread of alleles conferring resistance to insecticides and also

  6. Relationship of Remote Sensing Normalized Differential Vegetation Index to Anopheles Density and Malaria Incidence Rate

    Institute of Scientific and Technical Information of China (English)

    2006-01-01

    To study the relationship of remote sensing normalized differential vegetation index (NDVI) to Anopheles density and malaria incidence rate. Methods Data of monthly average climate, environment, Anopheles density and malaria incidence rate, and remote sensing NDVI were collected from 27 townships of 10 counties in southeastern Yunnan Province from 1984 to 1993. The relationship of remote sensing ecological proxy index, NDVI, to Anopheles density and malaria incidence rate was studied by principal component analysis, factor analysis and grey correlation analysis. Results The correlation matrix showed that NDVI highly correlated with Anopheles density in 4 townships of Mengla, Jinghong, and Yuanjiang counties, but in other 23 townships the relationship was not clear. Principal component and factor analyses showed that remote sensing NDVI was the representative index of the first principal component and the first common factor of Anopheles density evaluation. Grey correlation analysis showed that in rainy season NDVI had a high grey correlation with Anopheles density and malaria incidence rate. The grey correlation analysis showed that in rainy season the grey degree of NDVI correlated with Anopheles. Minimus density was 0.730, and 0.713 with Anopheles sinensis density, and 0.800 with malarial incidence rate. Conclusion Remote sensing NDVI can serve as a sensitive evaluation index of Anopheles density and malaria incidence rate.

  7. Seasonality and Locality Affect the Diversity of Anopheles gambiae and Anopheles coluzzii Midgut Microbiota from Ghana.

    Science.gov (United States)

    Akorli, Jewelna; Gendrin, Mathilde; Pels, Nana Adjoa P; Yeboah-Manu, Dorothy; Christophides, George K; Wilson, Michael D

    2016-01-01

    Symbiotic bacteria can have important implications in the development and competence of disease vectors. In Anopheles mosquitoes, the composition of the midgut microbiota is largely influenced by the larval breeding site, but the exact factors shaping this composition are currently unknown. Here, we examined whether the proximity to urban areas and seasons have an impact on the midgut microbial community of the two major malaria vectors in Africa, An. coluzzii and An. gambiae. Larvae and pupae were collected from selected habitats in two districts of Ghana during the dry and rainy season periods. The midgut microbiota of adults that emerged from these collections was determined by 454-pyrosequencing of the 16S ribosomal DNA. We show that in both mosquito species, Shewanellaceae constituted on average of 54% and 73% of the midgut microbiota from each site in the dry and rainy season, respectively. Enterobacteriaceae was found in comparatively low abundance below 1% in 22/30 samples in the dry season, and in 25/38 samples in the rainy season. Our data indicate that seasonality and locality significantly affect both the diversity of microbiota and the relative abundance of bacterial families with a positive impact of dry season and peri-urban settings.

  8. Seasonality and Locality Affect the Diversity of Anopheles gambiae and Anopheles coluzzii Midgut Microbiota from Ghana

    Science.gov (United States)

    Gendrin, Mathilde; Pels, Nana Adjoa P.; Yeboah-Manu, Dorothy; Christophides, George K.; Wilson, Michael D.

    2016-01-01

    Symbiotic bacteria can have important implications in the development and competence of disease vectors. In Anopheles mosquitoes, the composition of the midgut microbiota is largely influenced by the larval breeding site, but the exact factors shaping this composition are currently unknown. Here, we examined whether the proximity to urban areas and seasons have an impact on the midgut microbial community of the two major malaria vectors in Africa, An. coluzzii and An. gambiae. Larvae and pupae were collected from selected habitats in two districts of Ghana during the dry and rainy season periods. The midgut microbiota of adults that emerged from these collections was determined by 454-pyrosequencing of the 16S ribosomal DNA. We show that in both mosquito species, Shewanellaceae constituted on average of 54% and 73% of the midgut microbiota from each site in the dry and rainy season, respectively. Enterobacteriaceae was found in comparatively low abundance below 1% in 22/30 samples in the dry season, and in 25/38 samples in the rainy season. Our data indicate that seasonality and locality significantly affect both the diversity of microbiota and the relative abundance of bacterial families with a positive impact of dry season and peri-urban settings. PMID:27322614

  9. Locomotor behavioral responses of Anopheles minimus and Anopheles harrisoni to alpha-cypermethrin in Thailand.

    Science.gov (United States)

    Malaithong, Naritsara; Tisgratog, Rungarun; Tainchum, Krajana; Prabaripai, Atchariya; Juntarajumnong, Waraporn; Bangs, Michael J; Chareonviriyaphap, Theeraphap

    2011-09-01

    Excito-repellency responses of 3 test populations, representing 2 sibling species within the Minimus Complex, Anopheles minimus and An. harrisoni, were characterized for contact irritant and noncontact repellent actions of chemicals during and after exposure to alpha-cypermethrin at half the recommended field (0.010 g/m2), the recommended field (0.020 g/m2), and double the recommended field concentration (0.040 g/m2), using an excito-repellency escape chamber system. Two field populations of An. minimus and An. harrisoni collected from the malaria-endemic areas in Tak and Kanchanuburi provinces in western Thailand, respectively, were tested along with a laboratory population of An. minimus maintained since 1993. Females of all 3 test populations rapidly escaped after direct contact with treated surfaces for each concentration. In general, increased escape responses in the An. minimus test populations were proportionate to increased insecticide dosages. The greatest escape response for An. harrisoni was observed at the operational field concentration of alpha-cypermethrin. The noncontact repellency response to alpha-cypermethrin was comparatively weak for all 3 test populations, but significantly different from each paired contact test and respective noncontact controls. We conclude that strong contact irritancy is a major action of alpha-cypermethrin, whereas noncontact repellency plays no role in the escape responses of 2 species in the Minimus Complex in Thailand.

  10. On the conspecificity of Anopheles fluviatilis species S with Anopheles minimus species C

    Indian Academy of Sciences (India)

    O P Singh; D Chandra; N Nanda; S K Sharma; Pe Than Htun; T Adak; S K Subbarao; A P Dash

    2006-12-01

    Anopheles fluviatilis and An. minimus complexes, each comprising of at least three sibling species, are closely related and important malaria vectors in Oriental Region. Recently An. fluviatilis species S, which is a highly efficient malaria vector in India, has been made conspecific with An. minimus species C (senior synonym) on the basis of homology in 335 base pair nucleotide sequence of D3 domain of 28S ribosomal DNA (rDNA). We examined the conspecificity of these two nominal species by obtaining and analysing the DNA sequences of nuclear ribosomal loci internal transcribed spacer 2 (ITS2) and D2-D3 domain of 28S rDNA (28S-D2/D3) from those of An. fluviatilis S and An. minimus C. We found that the sequences of An. fluviatilis S are appreciably different from those of An. minimus C with pair-wise distance (Kimura-2-parametre model) of 3.6 and 0.7% for loci ITS2 and 28S-D2/D3, respectively. Pair-wise distance and phylogenetic analyses using ITS2 sequences of members of Minimus and Fluviatilis Complexes revealed that An. fluviatilis S is distantly related to An. minimus C as compared to any other members of the Fluviatilis Complex. These findings suggest that the two nominal species, An. fluviatilis S and An. minimus C, do not merit synonymy. The study also confirms that the reported species An. fluviatilis X is synonym with species S.

  11. Evaluating the potential of the sterile insect technique for malaria control: relative fitness and mating compatibility between laboratory colonized and a wild population of Anopheles arabiensis from the Kruger National Park, South Africa

    OpenAIRE

    Hunt Richard H; Chirwa Tobias F; Brooke Basil D; Munhenga Givemore; Coetzee Maureen; Govender Danny; Koekemoer Lizette L

    2011-01-01

    Abstract Background The successful suppression of a target insect population using the sterile insect technique (SIT) partly depends on the premise that the laboratory insects used for mass rearing are genetically compatible with the target population, that the mating competitiveness of laboratory reared males is at least comparable to that of their wild counterparts, and that mass rearing and sterilization processes do not in themselves compromise male fitness to a degree that precludes them...

  12. Mating competitiveness of sterile male Anopheles coluzzii in large cages

    OpenAIRE

    Maïga, H.; Damiens, D.; Niang, A.; Sawadogo, SP; Fatherhaman, O.; Lees, RS; Roux, O.; Dabiré, RK; Ouédraogo, GA; Tripet, F; Diabaté, A.; Gilles, JR

    2014-01-01

    Background: Understanding the factors that account for male mating competitiveness is critical to the development of the sterile insect technique (SIT). Here, the effects of partial sterilization with 90 Gy of radiation on sexual competitiveness of Anopheles coluzzii allowed to mate in different ratios of sterile to untreated males have been assessed. Moreover, competitiveness was compared between males allowed one versus two days of contact with females. Methods: Sterile and untreated males ...

  13. In depth annotation of the Anopheles gambiae mosquito midgut transcriptome

    OpenAIRE

    Padrón, Alejandro; Molina-Cruz, Alvaro; Quinones, Mariam; Ribeiro, José MC; Ramphul, Urvashi; Rodrigues, Janneth; Shen, Kui; Haile, Ashley; Ramirez, José Luis; Barillas-Mury, Carolina

    2014-01-01

    Background Genome sequencing of Anopheles gambiae was completed more than ten years ago and has accelerated research on malaria transmission. However, annotation needs to be refined and verified experimentally, as most predicted transcripts have been identified by comparative analysis with genomes from other species. The mosquito midgut—the first organ to interact with Plasmodium parasites—mounts effective antiplasmodial responses that limit parasite survival and disease transmission. High-th...

  14. Highly evolvable malaria vectors : the genomes of 16 Anopheles mosquitoes

    OpenAIRE

    Neafsey, Daniel E; Waterhouse, Robert M.; Abai, Mohammad R.; Aganezov, Sergey S.; Alekseyev, Max A.; Allen, James E.; Amon, James; Arcà, Bruno; Arensburger, Peter; Artemov, Gleb; Assour, Lauren A.; Basseri, Hamidreza; Berlin, Aaron; Birren, Bruce W.; Blandin, Stephanie A.

    2015-01-01

    Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning similar to 100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromos...

  15. The Anopheles community and the role of Anopheles minimus on malaria transmission on the China-Myanmar border

    OpenAIRE

    Yu, Guo; Yan, Guiyun; Zhang, Naixin; Zhong, Daibin; Wang, Ying(School of Physics, Shandong University, Jinan, 250100, PR China); He, Zhengbo; Yan, Zhentian; Fu, Wenbo; Yang, Feilong; Chen, Bin

    2013-01-01

    Abstract Background Malaria around the China-Myanmar border is a serious health problem in the countries of South-East Asia. An. minimus is a principle malaria vector with a wide geographic distribution in this area. Malaria is endemic along the boundary between Yunnan province in China and the Kachin State of Myanmar where the local Anopheles community (species composition) and the malaria transmission vectors have never been clarified. ...

  16. The role of reactive oxygen species on Plasmodium melanotic encapsulation in Anopheles gambiae

    OpenAIRE

    Kumar, Sanjeev; Christophides, George K.; Cantera, Rafael; Charles, Bradley; Han, Yeon Soo; Meister, Stephan; Dimopoulos, George; Kafatos, Fotis C.; Barillas-Mury, Carolina

    2003-01-01

    Malaria transmission depends on the competence of some Anopheles mosquitoes to sustain Plasmodium development (susceptibility). A genetically selected refractory strain of Anopheles gambiae blocks Plasmodium development, melanizing, and encapsulating the parasite in a reaction that begins with tyrosine oxidation, and involves three quantitative trait loci. Morphological and microarray mRNA expression analysis suggest that the refractory and susceptible strains have broad physiological differe...

  17. Dicty_cDB: Contig-U04390-1 [Dicty_cDB

    Lifescience Database Archive (English)

    Full Text Available nt EP1865317. 38 2.2 5 ( EU881867 ) Anopheles arabiensis isolate TzN9_S TEP1 gene, pa... 42 2.2 2 ( AE014841...o sapiens Chromosome 15q11-q13 PAC clone pDJ35... 44 4.0 2 ( EU881839 ) Anopheles arabiensis isolate ToMB7_S

  18. Cotton pest management practices and the selection of pyrethroid resistance in Anopheles gambiae population in Northern Benin

    Directory of Open Access Journals (Sweden)

    Yadouleton Anges

    2011-04-01

    Full Text Available Abstract Background Pyrethroid insecticides, carbamate and organophosphate are the classes of insecticides commonly used in agriculture for crop protection in Benin. Pyrethroids remain the only class of insecticides recommended by the WHO for impregnation of bed nets. Unfortunately, the high level of pyrethroid resistance in Anopheles gambiae s.l., threatens to undermine the success of pyrethroid treated nets. This study focuses on the investigation of agricultural practices in cotton growing areas, and their direct impact on larval populations of An. gambiae in surrounding breeding sites. Methods The protocol was based on the collection of agro-sociological data where farmers were subjected to semi-structured questionnaires based on the strategies used for crop protection. This was complemented by bioassay tests to assess the susceptibility of malaria vectors to various insecticides. Molecular analysis was performed to characterize the resistance genes and the molecular forms of An. gambiae. Insecticide residues in soil samples from breeding sites were investigated to determine major factors that can inhibit the normal growth of mosquito larvae by exposing susceptible and resistant laboratory strains. Results There is a common use by local farmers of mineral fertilizer NPK at 200 kg/ha and urea at 50 kg/hectare following insecticide treatments in both the Calendar Control Program (CCP and the Targeted Intermittent Control Program (TICP. By contrast, no chemicals are involved in Biological Program (BP where farmers use organic and natural fertilizers which include animal excreta. Susceptibility test results confirmed a high resistance to DDT. Mean mortality of An. gambiae collected from the farms practicing CCP, TICP and BP methods were 33%, 42% and 65% respectively. An. gambiae populations from areas using the CCP and TICP programs showed resistance to permethrin with mortality of 50% and 58% respectively. By contrast, bioassay test results of

  19. Immunity-related genes and gene families in Anopheles gambiae.

    Science.gov (United States)

    Christophides, George K; Zdobnov, Evgeny; Barillas-Mury, Carolina; Birney, Ewan; Blandin, Stephanie; Blass, Claudia; Brey, Paul T; Collins, Frank H; Danielli, Alberto; Dimopoulos, George; Hetru, Charles; Hoa, Ngo T; Hoffmann, Jules A; Kanzok, Stefan M; Letunic, Ivica; Levashina, Elena A; Loukeris, Thanasis G; Lycett, Gareth; Meister, Stephan; Michel, Kristin; Moita, Luis F; Müller, Hans-Michael; Osta, Mike A; Paskewitz, Susan M; Reichhart, Jean-Marc; Rzhetsky, Andrey; Troxler, Laurent; Vernick, Kenneth D; Vlachou, Dina; Volz, Jennifer; von Mering, Christian; Xu, Jiannong; Zheng, Liangbiao; Bork, Peer; Kafatos, Fotis C

    2002-10-01

    We have identified 242 Anopheles gambiae genes from 18 gene families implicated in innate immunity and have detected marked diversification relative to Drosophila melanogaster. Immune-related gene families involved in recognition, signal modulation, and effector systems show a marked deficit of orthologs and excessive gene expansions, possibly reflecting selection pressures from different pathogens encountered in these insects' very different life-styles. In contrast, the multifunctional Toll signal transduction pathway is substantially conserved, presumably because of counterselection for developmental stability. Representative expression profiles confirm that sequence diversification is accompanied by specific responses to different immune challenges. Alternative RNA splicing may also contribute to expansion of the immune repertoire. PMID:12364793

  20. CLIP proteases and Plasmodium melanization in Anopheles gambiae.

    Science.gov (United States)

    Barillas-Mury, Carolina

    2007-07-01

    Melanization is a potent immune response mediated by phenoloxidase (PO). Multiple Clip-domain serine proteases (CLIP) regulate PO activation as part of a complex cascade of proteases that are cleaved sequentially. The role of several CLIP as key activators or suppressors of the melanization responses of Anopheles gambiae to Plasmodium berghei (murine malaria) has been established recently using a genome-wide reverse genetics approach. Important differences in regulation of PO activation between An. gambiae strains were also identified. This review summarizes these findings and discusses our current understanding of the An. gambiae melanization responses to Plasmodium. PMID:17512801

  1. Evaluation of Insecticides Susceptibility and Malaria Vector Potential of Anopheles annularis s.l. and Anopheles vagus in Assam, India

    Science.gov (United States)

    Dhiman, Sunil; Yadav, Kavita; Rabha, Bipul; Goswami, Diganta; Hazarika, S.; Tyagi, Varun

    2016-01-01

    During the recent past, development of DDT resistance and reduction to pyrethroid susceptibility among the malaria vectors has posed a serious challenge in many Southeast Asian countries including India. Current study presents the insecticide susceptibility and knock-down data of field collected Anopheles annularis sensu lato and An. vagus mosquito species from endemic areas of Assam in northeast India. Anopheles annularis s.l. and An. vagus adult females were collected from four randomly selected sentinel sites in Orang primary health centre (OPHC) and Balipara primary health centre (BPHC) areas, and used for testing susceptibility to DDT, malathion, deltamethrin and lambda-cyhalothrin. After insecticide susceptibility tests, mosquitoes were subjected to VectorTest™ assay kits to detect the presence of malaria sporozoite in the mosquitoes. An. annularis s.l. was completely susceptible to deltamethrin, lambda-cyhalothrin and malathion in both the study areas. An. vagus was highly susceptible to deltamethrin in both the areas, but exhibited reduced susceptibility to lambda-cyhalothrin in BPHC. Both the species were resistant to DDT and showed very high KDT50 and KDT99 values for DDT. Probit model used to calculate the KDT50 and KDT99 values did not display normal distribution of percent knock-down with time for malathion in both the mosquito species in OPHC (pp = 0.0), and also for deltamethrin to An. vagus in BPHC area (χ2 = 15.4; p = 0.004). Minimum infection rate (MIR) of Plasmodium sporozoite for An. vagus was 0.56 in OPHC and 0.13 in BPHC, while for An. annularis MIR was found to be 0.22 in OPHC. Resistance management strategies should be identified to delay the expansion of resistance. Testing of field caught Anopheles vectors from different endemic areas for the presence of malaria sporozoite may be useful to ensure their role in malaria transmission. PMID:27010649

  2. Evaluation of Insecticides Susceptibility and Malaria Vector Potential of Anopheles annularis s.l. and Anopheles vagus in Assam, India.

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    Sunil Dhiman

    Full Text Available During the recent past, development of DDT resistance and reduction to pyrethroid susceptibility among the malaria vectors has posed a serious challenge in many Southeast Asian countries including India. Current study presents the insecticide susceptibility and knock-down data of field collected Anopheles annularis sensu lato and An. vagus mosquito species from endemic areas of Assam in northeast India. Anopheles annularis s.l. and An. vagus adult females were collected from four randomly selected sentinel sites in Orang primary health centre (OPHC and Balipara primary health centre (BPHC areas, and used for testing susceptibility to DDT, malathion, deltamethrin and lambda-cyhalothrin. After insecticide susceptibility tests, mosquitoes were subjected to VectorTest™ assay kits to detect the presence of malaria sporozoite in the mosquitoes. An. annularis s.l. was completely susceptible to deltamethrin, lambda-cyhalothrin and malathion in both the study areas. An. vagus was highly susceptible to deltamethrin in both the areas, but exhibited reduced susceptibility to lambda-cyhalothrin in BPHC. Both the species were resistant to DDT and showed very high KDT50 and KDT99 values for DDT. Probit model used to calculate the KDT50 and KDT99 values did not display normal distribution of percent knock-down with time for malathion in both the mosquito species in OPHC (p<0.05 and An. vagus in BPHC (χ2 = 25.3; p = 0.0, and also for deltamethrin to An. vagus in BPHC area (χ2 = 15.4; p = 0.004. Minimum infection rate (MIR of Plasmodium sporozoite for An. vagus was 0.56 in OPHC and 0.13 in BPHC, while for An. annularis MIR was found to be 0.22 in OPHC. Resistance management strategies should be identified to delay the expansion of resistance. Testing of field caught Anopheles vectors from different endemic areas for the presence of malaria sporozoite may be useful to ensure their role in malaria transmission.

  3. "Insecticide Resistance /Susceptibility Monitoring in Anopheles pulcherrimus (Diptera: Culicidae in Ghasreghand District, Sistan and Baluchistan Province, Iran"

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    AH Zahirnia

    2002-08-01

    Full Text Available Two organochlorine, one organophosphate, two carbamate and two pyrethroid insecticides have been studied for their comparative study against fieldcollected An.pulcherrimus. The trail was conducted in Ghasreghand district, Sistan and Baluchistan province, Southeastern Iran using WHO impregnated papers at the diagnostic dose. Results revealed that this species exhibit resistant to 0.4% dieldrin (mortality 86 ± 2.07. Dose response regression line from interval exposure times to 0.4% dieldrin showed that LT50 and LT90 was 14 and 76 minutes, respectively. The efficacles of other insecticides such as 4% DDT, 5% malathion, 0.1% bendiocarb, 0.1% propoxur, 0.25% permethrin and 0.1% lambdacyhalothrin were maximum when mosquitoes exposed 1 hour at diagnostic dose followed by 24 hour recovery period.

  4. Bioinformatics-Based Identification of Chemosensory Proteins in African Malaria Mosquito, Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    Zhengxi Li; Zuorui Shen; Jingjiang Zhou; Lin Field

    2003-01-01

    Chemosensory proteins (CSPs) are identifiable by four spatially conserved Cysteine residues in their primary structure or by two disulfide bridges in their tertiary structure according to the previously identified olfactory specific-D related proteins. A genomics- and bioinformatics-based approach is taken in the present study to identify the putative CSPs in the malaria-carrying mosquito, Anopheles gambiae. The results show that five out of the nine annotated candidates are the most possible Anopheles CSPs of A. gambiae. This study lays the foundation for further functional identification of Anopheles CSPs, though all of these candidates need additional experimental verification.

  5. Droogboeketten als vector voor exoten (Diptera: Tephritidae)?

    OpenAIRE

    Smit, J.T.

    2006-01-01

    Everlasting flowers as a vector for exotic insects (Diptera: Tephritidae)? In this paper two rearing occasions of exotic fruit fly species of the genus Terellia are documented. Terellia fuscicornis (Loew, 1844) was reared from a ‘tropical’ plant (probably a thistle species) of unknown origin. Terellia longicauda (Meigen, 1830) was reared from Cirsium rivulare from southern France. On both occasions the plants were left to dry to serve as everlasting flowers. The differences between these exot...

  6. Anophelism in a former malaria area of northeastern Spain.

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    Rubén Bueno-Marí

    2013-12-01

    Full Text Available A field study on diversity and distribution of anophelines currently present in a past endemic malaria area of Spain was carried out in order to identify possible risk areas of local disease transmission.Multiple larval sites were sampled from June to October of 2011 in the Region of Somontano de Barbastro (Northeastern Spain. The sampling effort was fixed at 10 minutes which included the active search for larvae in each biotope visited.A total of 237 larval specimens belonging to four Anopheles species (Anopheles atroparvus, An. claviger, An. maculipennis and An. petragnani were collected and identified.Malaria receptivity in the study area is high, especially in the area of Cinca river valley, due to the abundance of breeding sites of An. atroparvus very close to human settlements. Although current socio-economic conditions in Spain reduce possibilities of re-emergence of malaria transmission, it is evident that certain entomological and epidemiological vigilance must be maintained and even increased in the context of current processes of climate change and globalization.

  7. A proteomic investigation of soluble olfactory proteins in Anopheles gambiae.

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    Guido Mastrobuoni

    Full Text Available Odorant-binding proteins (OBPs and chemosensory proteins (CSPs are small soluble polypeptides that bind semiochemicals in the lymph of insect chemosensilla. In the genome of Anopheles gambiae, 66 genes encode OBPs and 8 encode CSPs. Here we monitored their expression through classical proteomics (2D gel-MS analysis and a shotgun approach. The latter method proved much more sensitive and therefore more suitable for tiny biological samples as mosquitoes antennae and eggs. Females express a larger number and higher quantities of OBPs in their antennae than males (24 vs 19. OBP9 is the most abundant in the antennae of both sexes, as well as in larvae, pupae and eggs. Of the 8 CSPs, 4 were detected in antennae, while SAP3 was the only one expressed in larvae. Our proteomic results are in fairly good agreement with data of RNA expression reported in the literature, except for OBP4 and OBP5, that we could not identify in our analysis, nor could we detect in Western Blot experiments. The relatively limited number of soluble olfactory proteins expressed at relatively high levels in mosquitoes makes further studies on the coding of chemical messages at the OBP level more accessible, providing for few specific targets. Identification of such proteins in Anopheles gambiae might facilitate future studies on host finding behavior in this important disease vector.

  8. Numerous transitions of sex chromosomes in Diptera.

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    Beatriz Vicoso

    2015-04-01

    Full Text Available Many species groups, including mammals and many insects, determine sex using heteromorphic sex chromosomes. Diptera flies, which include the model Drosophila melanogaster, generally have XY sex chromosomes and a conserved karyotype consisting of six chromosomal arms (five large rods and a small dot, but superficially similar karyotypes may conceal the true extent of sex chromosome variation. Here, we use whole-genome analysis in 37 fly species belonging to 22 different families of Diptera and uncover tremendous hidden diversity in sex chromosome karyotypes among flies. We identify over a dozen different sex chromosome configurations, and the small dot chromosome is repeatedly used as the sex chromosome, which presumably reflects the ancestral karyotype of higher Diptera. However, we identify species with undifferentiated sex chromosomes, others in which a different chromosome replaced the dot as a sex chromosome or in which up to three chromosomal elements became incorporated into the sex chromosomes, and others yet with female heterogamety (ZW sex chromosomes. Transcriptome analysis shows that dosage compensation has evolved multiple times in flies, consistently through up-regulation of the single X in males. However, X chromosomes generally show a deficiency of genes with male-biased expression, possibly reflecting sex-specific selective pressures. These species thus provide a rich resource to study sex chromosome biology in a comparative manner and show that similar selective forces have shaped the unique evolution of sex chromosomes in diverse fly taxa.

  9. Isoenzymatic variability among five Anopheles species belonging to the Nyssorhynchus and Anopheles subgenera of the Amazon region, Brazil

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    Joselita Maria Mendes dos Santos

    2003-03-01

    Full Text Available An isoenzymatic comparative analysis of the variability and genetics differentiation among Anopheles species was done in populations of An. (Nys. intermedius and An. (Ano. mattogrossensis of the Anopheles subgenus, and of An. darlingi, An. albitarsis and An. triannulatus of the Nyssorhynchus subgenus, with the aim of detecting differences between both subgenera and of estimating the degree of genetic intere specific divergence. Samples from Macapá, State of Amapá and Janauari Lake, near Manaus, State of Amazonas, were analyzed for eight isoenzymatic loci. Analysis revealed differences in the average number of alleles per locus (1.6-2.3 and heterozygosity (0.060-0.284. However, the proportion of polymorphic loci was the same for An. (Nys. darlingi, An. (Nys. triannulatus and An. (Ano. mattogrossensis (50%, but differed for An. (Nys. albitarsis (62.5% and An. (Ano. intermedius (25%. Only the IDH1 (P > 0.5 locus in all species studied was in Hardy-Weinberg equilibrium. The fixation index demonstrated elevated genetic structuring among species, based on values of Fst = 0.644 and genetic distance (0.344-0.989. Genetic difference was higher between An. (Nys. triannulatus and An. (Ano. intermedius (0.989 and smaller between An. (Nys. albitarsis sensu lato and An. (Nys. darlingi (0.344. The data show interspecific genetic divergence which differs from the phylogenetic hypothesis based on morphological characters.

  10. Limited usefulness of microsatellite markers from the malaria vector Anopheles gambiae when applied to the closely related species Anopheles melas.

    Science.gov (United States)

    Deitz, Kevin C; Reddy, Vamsi P; Reddy, Michael R; Satyanarayanah, Neha; Lindsey, Michael W; Overgaard, Hans J; Jawara, Musa; Caccone, Adalgisa; Slotman, Michel A

    2012-07-01

    Anopheles melas is a brackish water mosquito found in coastal West Africa where it is a dominant malaria vector locally. In order to facilitate genetic studies of this species, 45 microsatellite loci originally developed for Anopheles gambiae were sequenced in An. melas. Those that were suitable based on repeat number and flanking regions were examined in 2 natural populations from Equatorial Guinea. Only 15 loci were eventually deemed suitable as polymorphic markers in An. melas populations. These loci were screened in 4 populations from a wider geographic range. Heterozygosity estimates ranged from 0.18 to 0.79, and 2.5-15 average alleles were observed per locus, yielding 13 highly polymorphic markers and 2 loci with lower variability. To examine the usefulness of microsatellite markers when applied in a sibling species, the original An. gambiae specific markers were used to amplify 5 loci in An. melas. Null alleles were found for 1 An. gambiae marker. We discuss the pitfalls of using microsatellite loci across closely related species and conclude that in addition to the problem of null alleles associated with this practice, many loci may prove to be of very limited use as polymorphic markers even when used in a sibling species. PMID:22593601

  11. Evaluation of Insecticides Susceptibility and Malaria Vector Potential of Anopheles annularis s.l. and Anopheles vagus in Assam, India.

    Science.gov (United States)

    Dhiman, Sunil; Yadav, Kavita; Rabha, Bipul; Goswami, Diganta; Hazarika, S; Tyagi, Varun

    2016-01-01

    During the recent past, development of DDT resistance and reduction to pyrethroid susceptibility among the malaria vectors has posed a serious challenge in many Southeast Asian countries including India. Current study presents the insecticide susceptibility and knock-down data of field collected Anopheles annularis sensu lato and An. vagus mosquito species from endemic areas of Assam in northeast India. Anopheles annularis s.l. and An. vagus adult females were collected from four randomly selected sentinel sites in Orang primary health centre (OPHC) and Balipara primary health centre (BPHC) areas, and used for testing susceptibility to DDT, malathion, deltamethrin and lambda-cyhalothrin. After insecticide susceptibility tests, mosquitoes were subjected to VectorTest™ assay kits to detect the presence of malaria sporozoite in the mosquitoes. An. annularis s.l. was completely susceptible to deltamethrin, lambda-cyhalothrin and malathion in both the study areas. An. vagus was highly susceptible to deltamethrin in both the areas, but exhibited reduced susceptibility to lambda-cyhalothrin in BPHC. Both the species were resistant to DDT and showed very high KDT50 and KDT99 values for DDT. Probit model used to calculate the KDT50 and KDT99 values did not display normal distribution of percent knock-down with time for malathion in both the mosquito species in OPHC (puseful to ensure their role in malaria transmission. PMID:27010649

  12. Mosquitoes (Diptera: Culicidae) and their relevance as disease vectors in the city of Vienna, Austria.

    Science.gov (United States)

    Lebl, Karin; Zittra, Carina; Silbermayr, Katja; Obwaller, Adelheid; Berer, Dominik; Brugger, Katharina; Walter, Melanie; Pinior, Beate; Fuehrer, Hans-Peter; Rubel, Franz

    2015-02-01

    Mosquitoes (Diptera: Culicidae) are important vectors for a wide range of pathogenic organisms. As large parts of the human population in developed countries live in cities, the occurrence of vector-borne diseases in urban areas is of particular interest for epidemiologists and public health authorities. In this study, we investigated the mosquito occurrence in the city of Vienna, Austria, in order to estimate the risk of transmission of mosquito-borne diseases. Mosquitoes were captured using different sampling techniques at 17 sites in the city of Vienna. Species belonging to the Culex pipiens complex (78.8 %) were most abundant, followed by Coquillettidia richiardii (10.2 %), Anopheles plumbeus (5.4 %), Aedes vexans (3.8 %), and Ochlerotatus sticticus (0.7 %). Individuals of the Cx. pipiens complex were found at 80.2 % of the trap sites, while 58.8 % of the trap sites were positive for Cq. richiardii and Ae. vexans. Oc. sticticus was captured at 35.3 % of the sites, and An. plumbeus only at 23.5 % of the trap sites. Cx. pipiens complex is known to be a potent vector and pathogens like West Nile virus (WNV), Usutu virus (USUV), Tahyna virus (TAHV), Sindbis virus (SINV), Plasmodium sp., and Dirofilaria repens can be transmitted by this species. Cq. richiardii is a known vector species for Batai virus (BATV), SINV, TAHV, and WNV, while Ae. vexans can transmit TAHV, USUV, WNV, and Dirofilaria repens. An. plumbeus and Oc. sticticus seem to play only a minor role in the transmission of vector-borne diseases in Vienna. WNV, which is already wide-spread in Europe, is likely to be the highest threat in Vienna as it can be transmitted by several of the most common species, has already been shown to pose a higher risk in cities, and has the possibility to cause severe illness.

  13. Evidence of natural Wolbachia infections in field populations of Anopheles gambiae

    Science.gov (United States)

    Baldini, Francesco; Segata, Nicola; Pompon, Julien; Marcenac, Perrine; Robert Shaw, W.; Dabiré, Roch K.; Diabaté, Abdoulaye; Levashina, Elena A.; Catteruccia, Flaminia

    2014-01-01

    Wolbachia are maternally transmitted intracellular bacteria that invade insect populations by manipulating their reproduction and immunity and thus limiting the spread of numerous human pathogens. Experimental Wolbachia infections can reduce Plasmodium numbers in Anopheles mosquitoes in the laboratory, however, natural Wolbachia infections in field anophelines have never been reported. Here we show evidence of Wolbachia infections in Anopheles gambiae in Burkina Faso, West Africa. Sequencing of the 16S rRNA gene identified Wolbachia sequences in both female and male germlines across two seasons, and determined that these sequences are vertically transmitted from mother to offspring. Whole-genome sequencing of positive samples suggests that the genetic material identified in An. gambiae belongs to a novel Wolbachia strain, related to but distinct from strains infecting other arthropods. The evidence of Wolbachia infections in natural Anopheles populations promotes further investigations on the possible use of natural Wolbachia–Anopheles associations to limit malaria transmission. PMID:24905191

  14. ANOSPEX: a stochastic, spatially explicit model for studying Anopheles metapopulation dynamics.

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    Olugbenga O Oluwagbemi

    Full Text Available Anopheles mosquitoes transmit malaria, a major public health problem among many African countries. One of the most effective methods to control malaria is by controlling the Anopheles mosquito vectors that transmit the parasites. Mathematical models have both predictive and explorative utility to investigate the pros and cons of different malaria control strategies. We have developed a C++ based, stochastic spatially explicit model (ANOSPEX; Ano pheles Spatially-Explicit to simulate Anopheles metapopulation dynamics. The model is biologically rich, parameterized by field data, and driven by field-collected weather data from Macha, Zambia. To preliminarily validate ANOSPEX, simulation results were compared to field mosquito collection data from Macha; simulated and observed dynamics were similar. The ANOSPEX model will be useful in a predictive and exploratory manner to develop, evaluate and implement traditional and novel strategies to control malaria, and for understanding the environmental forces driving Anopheles population dynamics.

  15. Chemical Composition and Repellent Activity of Achillea vermiculata and Satureja hortensis against Anopheles stephensi

    OpenAIRE

    Masoumeh Pirmohammadi; Mansoureh Shayeghi; Hassan Vatandoost; Mohammad Reza Abaei; Ali Mohammadi; Akbar Bagheri; Mehdi Khoobdel; Hasan Bakhshi; Maryam Pirmohammadi; Maryam Tavassoli

    2016-01-01

    Background: One of the best ways to control the malaria disease and to be protected human against Anopheles mos­quito biting is the use of repellents. Throughout repellents, herbal ones may be an appropriate and safe source for protection.Methods: Chemical constituents of Achillea vermiculata and Satoreja hortensis were determined by using gas chromatography-mass spectrometry. Efficacy and the protection time of these plants were assessed on Anopheles stephensi under the laboratory condition....

  16. Comparative evaluation of systemic drugs for their effects against Anopheles gambiae

    OpenAIRE

    Butters, Matthew P.; Kobylinski, Kevin C.; Deus, Kelsey M.; da Silva, Ines Marques; GRAY, MEG; sylla, massamba; Foy, Brian D.

    2011-01-01

    Laboratory and field studies have shown that ivermectin, a drug that targets invertebrate ligand-gated ion channels (LGICs), is potently active against Anopheles spp. mosquitoes at concentrations present in human blood after standard drug administrations; thus ivermectin holds promise as a mass human-administered endectocide that could help suppress malaria parasite transmission. We evaluated other systemic LGIC-targeting drugs for their activities against the African malaria vector Anopheles...

  17. Biting patterns and host preference of Anopheles epiroticus in Chang Island, Trat Province, Eastern Thailand

    OpenAIRE

    Ritthison, W.; Tainchum, K.; Manguin, Sylvie; Bangs, M.J.; Chareonviriyaphap, T.

    2014-01-01

    A study of species diversity of Anopheles mosquitoes, biting patterns, and seasonal abundance of important mosquito vectors was conducted in two villages of Chang Island, Trat Province, in eastern Thailand, one located along the coast and the other in the low hills of the central interior of the island. Of 5,399 captured female anophelines, 70.25% belong to the subgenus Cellia and remaining specimens to the subgenus Anopheles. Five important putative malaria vectors were molecularly identifie...

  18. Entomological indices of Anopheles gambiae sensu lato at a rural community in south-west Nigeria

    OpenAIRE

    M.A.E. Noutcha; C.I. Anumdu

    2009-01-01

    Background & objectives: Investigations were conducted to obtain key entomological indices of Anopheles gambiae s.l. at Igbo-Ora, a rural community in south-west Nigeria. Methods: Mosquitoes were caught daily for a week from rooms where tenants had slept the previous night in each of the four months June, July (2001), and August, September (2002). Anopheles gambiae s.l. sibling species were PCR-identified, the blood meal origin was determined by direct ELISA, and the circumsporozoite antigen ...

  19. Factors influencing the spatial distribution of Anopheles larvae in Coimbatore District, Tamil Nadu, India.

    Science.gov (United States)

    Arjunan, Naresh Kumar; Kadarkarai, Murugan; Kumar, Shobana; Pari, Madhiyazhagan; Thiyagarajan, Nataraj; Vincent, C Thomas; Barnard, Donald R

    2015-12-01

    Malaria causes extensive morbidity and mortality in humans and results in significant economic losses in India. The distribution of immature malaria-transmitting Anopheles mosquitoes was studied in 17 villages in Coimbatore District as a prelude to the development and implementation of vector control strategies that are intended to reduce the risk of human exposure to potentially infectious mosquitoes. Eight Anopheles species were recorded. The most numerous species were Anopheles vagus, Anopheles subpictus, and Anopheles hyrcanus. The location of mosquito development sites and the density of larvae in each village was evaluated for correlation with selected demographic, biologic, and land use parameters using remote sensing and geographic information systems (GIS) technology. We found the number of mosquito development sites in a village and the density of larvae in such sites to be positively correlated with human population density but not the surface area (km(2)) of the village. The number of mosquito development sites and the density of larvae in each site were not correlated. Data from this study are being used to construct a GIS-based mapping system that will enable the location of aquatic habitats with Anopheles larvae in the Coimbatore District, Tamil Nadu, India as target sites for the application of vector control. PMID:26364718

  20. Influence of Land-use on the Fitness of Anopheles gambiae, the Principal Vector of Malaria in Nigeria

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    Israel Kayode Olayemi

    2009-02-01

    Full Text Available Background: Urbanization often results in profound environmental alterations that may promote the transmission of malaria. Though, land-use practices in urban areas have been linked with proliferations of suitable larval breeding habitats of malaria vectors, no attempt has been made to systematically investigate the influence of land-use practices on malaria transmission in Nigeria. Objectives: To elucidate the influence of land-use practices on larval development and adult body size of Anopheles gambiae (Diptera: Culicidae mosquitoes in Minna, Nigeria. Materials and Methods: Newly-hatched larvae of An. gmbiae mosquitoes were reared in semi-natural habitats stationed in five different sites, each representing the major land-use types in the area. The larvae were monitored daily for Duration of Immature Development (DID and Immature Survival Rate (ISR; while Wing Length (WL was used as an index of adult body size. Results: DID, ISR and WL varied significantly (P < 0.05 among the land-use categories; with lager numbers of bigger mosquitoes produced at a faster rate in the artificial than natural land-use sites. Water temperature for larval development was best in the Refuse Dump (RD site (mean = 28.11 ± 2.50oC and consequently the shortest DID (mean = 9.70 ± 0.74 days, as well as, the largest mosquitoes (mean WL = 3.10 ± 0.90 mm, were recorded in this land-use category. However, while ISR was highest (mean = 96.30 ± 2.78% in Farm Land (FL, the mosquitoes that emerged from this site were the smallest (mean WL = 1.96 ± 0.51mm. The Natural Vegetation (NV land-use category was the least productive, as the larvae took the longest time (13.29 ± 1.69 days to develop, and survived least (42.94 ± 7.50% in this site. Conclusion: The land-use practices in Minna enhanced the fitness of An. gambiae, and may increase the vectorial capacity of the species for malaria transmission in the area. Targeted larviciding interventions will greatly contribute to

  1. The familes Lonchopteridae, Opetiidae and Pipunculidae of Malta (Diptera, Aschiza)

    OpenAIRE

    Ebejer, Martin J.

    2012-01-01

    An account is given of the three Aschiza families of Diptera: one species of Lonchopteridae, one species of Opetiidae and four species of Pipunculidae that occur in Malta and which are all new records for this country

  2. Inhibition of Anopheles gambiae odorant receptor function by mosquito repellents.

    Science.gov (United States)

    Tsitoura, Panagiota; Koussis, Konstantinos; Iatrou, Kostas

    2015-03-20

    The identification of molecular targets of insect repellents has been a challenging task, with their effects on odorant receptors (ORs) remaining a debatable issue. Here, we describe a study on the effects of selected mosquito repellents, including the widely used repellent N,N-diethyl-meta-toluamide (DEET), on the function of specific ORs of the African malaria vector Anopheles gambiae. This study, which has been based on quantitative measurements of a Ca(2+)-activated photoprotein biosensor of recombinant OR function in an insect cell-based expression platform and a sequential compound addition protocol, revealed that heteromeric OR (ORx/Orco) function was susceptible to strong inhibition by all tested mosquito repellents except DEET. Moreover, our results demonstrated that the observed inhibition was due to efficient blocking of Orco (olfactory receptor coreceptor) function. This mechanism of repellent action, which is reported for the first time, is distinct from the mode of action of other characterized insect repellents including DEET. PMID:25657000

  3. Organization of olfactory centres in the malaria mosquito Anopheles gambiae

    Science.gov (United States)

    Riabinina, Olena; Task, Darya; Marr, Elizabeth; Lin, Chun-Chieh; Alford, Robert; O'Brochta, David A.; Potter, Christopher J.

    2016-01-01

    Mosquitoes are vectors for multiple infectious human diseases and use a variety of sensory cues (olfactory, temperature, humidity and visual) to locate a human host. A comprehensive understanding of the circuitry underlying sensory signalling in the mosquito brain is lacking. Here we used the Q-system of binary gene expression to develop transgenic lines of Anopheles gambiae in which olfactory receptor neurons expressing the odorant receptor co-receptor (Orco) gene are labelled with GFP. These neurons project from the antennae and maxillary palps to the antennal lobe (AL) and from the labella on the proboscis to the suboesophageal zone (SEZ), suggesting integration of olfactory and gustatory signals occurs in this brain region. We present detailed anatomical maps of olfactory innervations in the AL and the SEZ, identifying glomeruli that may respond to human body odours or carbon dioxide. Our results pave the way for anatomical and functional neurogenetic studies of sensory processing in mosquitoes. PMID:27694947

  4. Insecticide resistance status in Anopheles gambiae in southern Benin

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    Corbel Vincent

    2010-03-01

    Full Text Available Abstract Background The emergence of pyrethroid resistance in Anopheles gambiae has become a serious concern to the future success of malaria control. In Benin, the National Malaria Control Programme has recently planned to scaling up long-lasting insecticidal nets (LLINs and indoor residual spraying (IRS for malaria prevention. It is, therefore, crucial to monitor the level and type of insecticide resistance in An. gambiae, particularly in southern Benin where reduced efficacy of insecticide-treated nets (ITNs and IRS has previously been reported. Methods The protocol was based on mosquito collection during both dry and rainy seasons across forty districts selected in southern Benin. Bioassay were performed on adults collected from the field to assess the susceptibility of malaria vectors to insecticide-impregnated papers (permethrin 0.75%, delthamethrin 0.05%, DDT 4%, and bendiocarb 0.1% following WHOPES guidelines. The species within An. gambiae complex, molecular form and presence of kdr and ace-1 mutations were determined by PCR. Results Strong resistance to permethrin and DDT was found in An. gambiae populations from southern Benin, except in Aglangandan where mosquitoes were fully susceptible (mortality 100% to all insecticides tested. PCR showed the presence of two sub-species of An. gambiae, namely An. gambiae s.s, and Anopheles melas, with a predominance for An. gambiae s.s (98%. The molecular M form of An. gambiae was predominant in southern Benin (97%. The kdr mutation was detected in all districts at various frequency (1% to 95% whereas the Ace-1 mutation was found at a very low frequency (≤ 5%. Conclusion This study showed a widespread resistance to permethrin in An. gambiae populations from southern Benin, with a significant increase of kdr frequency compared to what was observed previously in Benin. The low frequency of Ace-1 recorded in all populations is encouraging for the use of bendiocarb as an alternative insecticide to

  5. Molecular Marker Confirmation for Member of Anopheles barbirostris Van Der Wulp 1884 in Different Localities

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    Tri Baskoro Tunggul Satoto

    2015-11-01

    Full Text Available Vector and non-vector forms of Anopheles barbirostris have been recognized in Indonesia. However, because of their similarity in morphology, they were considered to be a single species. This information has led to the hypothesis that Anopheles barbirostris is a complex of species, which are morphologically indistinguishable from each other by ordinary methods. Objectives of the research was to identify the member of Anopheles barbirostris by PCR Assay. Samples were taken from two localities in Java, two in Sulawesi, two in Flores Indonesia, one from Thailand, one from China. The study was to develop a PCR-based technique of rDNA ITS2 region. Results showed that there are at least four species within the Anopheles barbirostris population studied, namely Anopheles barbirostris species DW, DX, DY and DZ. The length of the sequence amplified for species W, species X, species Y, and species Z were 339bps, 247bps, 165bps. and 157bps, respectively. Verification of the method was carried out with 270 mosquitoes from eight different field-collection sites using various sampling methods. Samples collected from Singaraja-Flores were identified as species W and X. All specimens collected from human bite outdoors were identified as species X; this species showed to be predominant among indoor light trap, indoor human bite and indoor resting collections Samples from Reo-Flores were identified as species W and X. All specimens from Manado and Palopo in Sulawesiwere identified as species Z. Similarly only species Y was found in samples from Thailand, while specimens from Salaman and Jambu in Java were identified as species W or species X. These species-specific molecular markers for the Anopheles barbirostris, complex appear to be reliable over a wide geographical area. However, larger number of samples is still needed from throughout the range of this species.Key words: Anopheles barbirostris, ITS2, PCR, Specific primer diagnostic

  6. Applying Morphometric Variation of Seta 2 (Antepalmate Hair among the Larvae of the Members of the Maculipennis Subgroup (Diptera: Culicidae in Iran

    Directory of Open Access Journals (Sweden)

    S Doosti

    2007-06-01

    Full Text Available The members of Anopheles maculipennis subgroup (Diptera: Culicidae are the most important vectors of malaria in the north, west, and central plateau of Iran. This study was carried out to differentiate the species composition of this subgroup based on morphometric variation seta 2-IV and V (antepalmate hair among 149 larval specimens that were deposited at the Medical Arthropods Museum, the School of Public Health, Tehran University of Medical Sciences by using the light micro¬scope. The mean numbers of larval seta 2-IV and V of the specimens belong to different locations of Iran, were calculated by SPSS (11.5 software package, followed by cluster analysis, and four different groups (clusters were identified. The means were compared with the similar and available published data. After analyzing, four clusters recognized. The first cluster was fitted in ten localities in Esfahan, East Azarbaijan, West Azarbaijan, Khorassan, Kurdistan, and Mazandaran Provinces with its mean and standard deviation (SD of 14.89±1.13 (n= 79; the second group with one location in Gilan Province (11±1.58, no= 5; the third one with two locations in Fars and Western Azarbaijan Provinces (27.43±0.31, n=20, and the final group with four locations in Khuzestan, West Azarbaijan, and Qazvin Provinces (36.84±1.91, n= 45 were identified and corresponded to Anopheles messeae, An. atroparvus, An. melanoon, and An. sacharovi respectively. This work provides comparative information on the Maculipennis Subgroup based on morphometric examination at the larval stage in Iran.

  7. African water storage pots for the delivery of the Entomopathogenic fungus Metarhizium anisopliae to the Malaria vectors Anopheles gambiae s.s. and Anopheles funestus

    NARCIS (Netherlands)

    Farenhorst, M.; Farina, D.; Scholte, E.J.; Takken, W.; Hunt, R.H.; Coetzee, M.; Knols, B.G.J.

    2008-01-01

    We studied the use of African water storage pots for point source application of Metarhizium anisopliae against the malaria vectors Anopheles gambiae s.s. and An. funestus. Clay pots were shown to be attractive resting sites for male and female An. gambiae s.s. and were not repellent after impregnat

  8. The resting sites and blood-meal sources of Anopheles minimus in Taiwan

    Directory of Open Access Journals (Sweden)

    Chen Yung-Chen

    2008-06-01

    Full Text Available Abstract Background The WHO declared Taiwan free from malaria in 1965, but in 2003 the reporting of two introduced cases in a rural area suggested a possible local transmission of this disease. Therefore, understanding the resting sites and the blood sources of Anopheles minimus is crucial in order to provide information for implementing vector control strategies. Methods During a two-year survey, mosquitoes were collected in houses and their surrounding areas and at the bank of larval habitats by backpack aspirators in 17 villages in rural areas of southern and eastern Taiwan for 1 hr. On the same day, blacklight traps were hung downward overnight. Blood-fed mosquito samples were analysed by PCR. Results Of the 195 total households surveyed by backpack aspirators, no Anopheles adults were collected inside the houses, while a single Anopheles minimus and a single Anopheles maculatus were collected outside of the houses. On the same day, 23 An. minimus, two An. maculatus, two Anopheles ludlowae, two Anopheles sinensis, and one Anopheles tessellatus were collected along the bank of larval habitats. In blacklight traps hung outside of the houses in the villages, 69 An. minimus, 62 An. ludlowae, 31 An. sinensis, and 19 An. maculatus were collected. In larval habitats, 98 An. ludlowae, 64 An. minimus, 49 An. sinensis, and 14 An. maculatus were collected. Of a total of 10 blood-fed samples, An. minimus fed on four animals including bovine (60%, dogs (20%, pig (10%, and non-chicken avian (10%. Conclusion Anopheles minimus, an opportunist feeder in Taiwan, was not collected inside the houses, but was found outside of the houses in villages and surrounding larval habitats. Therefore, an outdoor transmission of malaria is likely to occur and, thus, the bed nets, which are favoured for controlling the late biting of An. minimus, should be a very efficient and effective method for those local residents who sleep outdoors. Additionally, space spray of

  9. Recombination rate predicts inversion size in Diptera.

    Science.gov (United States)

    Cáceres, M; Barbadilla, A; Ruiz, A

    1999-09-01

    Most species of the Drosophila genus and other Diptera are polymorphic for paracentric inversions. A common observation is that successful inversions are of intermediate size. We test here the hypothesis that the selected property is the recombination length of inversions, not their physical length. If so, physical length of successful inversions should be negatively correlated with recombination rate across species. This prediction was tested by a comprehensive statistical analysis of inversion size and recombination map length in 12 Diptera species for which appropriate data are available. We found that (1) there is a wide variation in recombination map length among species; (2) physical length of successful inversions varies greatly among species and is inversely correlated with the species recombination map length; and (3) neither the among-species variation in inversion length nor the correlation are observed in unsuccessful inversions. The clear differences between successful and unsuccessful inversions point to natural selection as the most likely explanation for our results. Presumably the selective advantage of an inversion increases with its length, but so does its detrimental effect on fertility due to double crossovers. Our analysis provides the strongest and most extensive evidence in favor of the notion that the adaptive value of inversions stems from their effect on recombination.

  10. Identification of one capa and two pyrokinin receptors from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Olsen, Stine S; Cazzamali, Giuseppe; Williamson, Michael;

    2007-01-01

    We cloned the cDNA of three evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae and functionally expressed them in Chinese hamster ovary cells. One receptor, Ang-Capa-R, was only activated by the two Anopheles capa neuropeptides Ang-capa-1 (GPTVGLFAFPRVa......We cloned the cDNA of three evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae and functionally expressed them in Chinese hamster ovary cells. One receptor, Ang-Capa-R, was only activated by the two Anopheles capa neuropeptides Ang-capa-1...... (GPTVGLFAFPRVamide) and Ang-capa-2 (pQGLVPFPRVamide) with EC(50) values of 8.6x10(-9)M and 3.3x10(-9)M, respectively, but not by any other known mosquito neuropeptide. The second receptor, Ang-PK-1-R, was selectively activated by the Anopheles pyrokinin-1 peptides Ang-PK-1-1 (AGGTGANSAMWFGPRLamide) and Ang-PK-1......-2 (AAAMWFGPRLamide) with EC(50) values of 3.3x10(-8)M and 2.5x10(-8)M, respectively, but not by mosquito capa or pyrokinin-2 peptides. For the third receptor, Ang-PK-2-R, the most potent ligands were the pyrokinin-2 peptides Ang-PK-2-1 (DSVGENHQRPPFAPRLamide) and Ang-PK-2-2 (NLPFSPRLamide) with EC(50) values of 5.2x...

  11. Mosquitoes (Diptera: Culicidae) of metropolitan Hamburg, Germany.

    Science.gov (United States)

    Krüger, A; Börstler, J; Badusche, M; Lühken, R; Garms, R; Tannich, E

    2014-08-01

    In Europe, mosquito-related public health concerns are growing due to the increasing spread of invasive mosquito species and the recent emergence of mosquito-borne arboviruses. A vital backbone in the assessment of these issues is detailed knowledge of the mosquito fauna, i.e. regional mosquito inventories. It was therefore decided to intensify nationwide investigations on the occurrence and distribution of mosquitoes in Germany in order to update old records and to detect possible faunal changes. This paper is focussing on a densely populated metropolitan region, the federal state of Hamburg and its adjacent environs, taking two historical baseline inventories into consideration, spanning almost 100 years of mosquito research in Hamburg. In the period between 2010 and 2014, more than 10,000 juvenile, neonate and adult mosquito specimens were sampled and trapped at 105 sites in Hamburg and its environs, of which about 60% have been identified to species level, resulting in a total of 33 recorded species. Of these, Anopheles algeriensis, Culex modestus, Ochlerotatus caspius, Ochlerotatus nigrinus and Ochlerotatus sticticus are new to the area. The most common species in Hamburg are Culex pipiens/torrentium and Ochlerotatus annulipes/cantans. In contrast, two previously common species, Anopheles atroparvus and Ochlerotatus excrucians, were not detected. Despite substantial environmental changes due to reconstruction, urbanisation and renaturation in the Hamburg metropolitan region in recent decades, there has been remarkably little change within the mosquito fauna during the last century. PMID:24870250

  12. Pyrethroid resistance in an Anopheles funestus population from Uganda.

    Directory of Open Access Journals (Sweden)

    John C Morgan

    Full Text Available BACKGROUND: The susceptibility status of Anopheles funestus to insecticides remains largely unknown in most parts of Africa because of the difficulty in rearing field-caught mosquitoes of this malaria vector. Here we report the susceptibility status of the An. funestus population from Tororo district in Uganda and a preliminary characterisation of the putative resistance mechanisms involved. METHODOLOGY/PRINCIPAL FINDINGS: A new forced egg laying technique used in this study significantly increased the numbers of field-caught females laying eggs and generated more than 4000 F1 adults. WHO bioassays indicated that An. funestus in Tororo is resistant to pyrethroids (62% mortality after 1 h exposure to 0.75% permethrin and 28% mortality to 0.05% deltamethrin. Suspected DDT resistance was also observed with 82% mortality. However this population is fully susceptible to bendiocarb (carbamate, malathion (organophosphate and dieldrin with 100% mortality observed after exposure to each of these insecticides. Sequencing of a fragment of the sodium channel gene containing the 1014 codon conferring pyrethroid/DDT resistance in An. gambiae did not detect the L1014F kdr mutation but a correlation between haplotypes and resistance phenotype was observed indicating that mutations in other exons may be conferring the knockdown resistance in this species. Biochemical assays suggest that resistance in this population is mediated by metabolic resistance with elevated level of GSTs, P450s and pNPA compared to a susceptible strain of Anopheles gambiae. RT-PCR further confirmed the involvement of P450s with a 12-fold over-expression of CYP6P9b in the Tororo population compared to the fully susceptible laboratory colony FANG. CONCLUSION: This study represents the first report of pyrethroid/DDT resistance in An. funestus from East Africa. With resistance already reported in southern and West Africa, this indicates that resistance in An. funestus may be more widespread

  13. Anopheles gambiae Purine Nucleoside Phosphorylase: Catalysis, Structure, and Inhibition

    Energy Technology Data Exchange (ETDEWEB)

    Taylor,E.; Rinaldo-Matthis, A.; Li, L.; Ghanem, M.; Hazleton, K.; Cassera, M.; Almo, S.; Schramm, V.

    2007-01-01

    The purine salvage pathway of Anopheles gambiae, a mosquito that transmits malaria, has been identified in genome searches on the basis of sequence homology with characterized enzymes. Purine nucleoside phosphorylase (PNP) is a target for the development of therapeutic agents in humans and purine auxotrophs, including malarial parasites. The PNP from Anopheles gambiae (AgPNP) was expressed in Escherichia coli and compared to the PNPs from Homo sapiens (HsPNP) and Plasmodium falciparum (PfPNP). AgPNP has kcat values of 54 and 41 s-1 for 2'-deoxyinosine and inosine, its preferred substrates, and 1.0 s-1 for guanosine. However, the chemical step is fast for AgPNP at 226 s-1 for guanosine in pre-steady-state studies. 5'-Deaza-1'-aza-2'-deoxy-1'-(9-methylene)-Immucillin-H (DADMe-ImmH) is a transition-state mimic for a 2'-deoxyinosine ribocation with a fully dissociated N-ribosidic bond and is a slow-onset, tight-binding inhibitor with a dissociation constant of 3.5 pM. This is the tightest-binding inhibitor known for any PNP, with a remarkable Km/Ki* of 5.4 x 107, and is consistent with enzymatic transition state predictions of enhanced transition-state analogue binding in enzymes with enhanced catalytic efficiency. Deoxyguanosine is a weaker substrate than deoxyinosine, and DADMe-Immucillin-G is less tightly bound than DADMe-ImmH, with a dissociation constant of 23 pM for AgPNP as compared to 7 pM for HsPNP. The crystal structure of AgPNP was determined in complex with DADMe-ImmH and phosphate to a resolution of 2.2 Angstroms to reveal the differences in substrate and inhibitor specificity. The distance from the N1' cation to the phosphate O4 anion is shorter in the AgPNP{center_dot}DADMe-ImmH{center_dot}PO4 complex than in HsPNP{center_dot}DADMe-ImmH{center_dot}SO4, offering one explanation for the stronger inhibitory effect of DADMe-ImmH for AgPNP.

  14. Bacterial diversity associated with wild caught Anopheles mosquitoes from Dak Nong Province, Vietnam using culture and DNA fingerprint.

    Directory of Open Access Journals (Sweden)

    Chung Thuy Ngo

    Full Text Available Microbiota of Anopheles midgut can modulate vector immunity and block Plasmodium development. Investigation on the bacterial biodiversity in Anopheles, and specifically on the identification of bacteria that might be used in malaria transmission blocking approaches, has been mainly conducted on malaria vectors of Africa. Vietnam is an endemic country for both malaria and Bancroftian filariasis whose parasitic agents can be transmitted by the same Anopheles species. No information on the microbiota of Anopheles mosquitoes in Vietnam was available previous to this study.The culture dependent approach, using different mediums, and culture independent (16S rRNA PCR - TTGE method were used to investigate the bacterial biodiversity in the abdomen of 5 Anopheles species collected from Dak Nong Province, central-south Vietnam. Molecular methods, sequencing and phylogenetic analysis were used to characterize the microbiota.The microbiota in wild-caught Anopheles was diverse with the presence of 47 bacterial OTUs belonging to 30 genera, including bacterial genera impacting Plasmodium development. The bacteria were affiliated with 4 phyla, Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria, the latter being the dominant phylum. Four bacterial genera are newly described in Anopheles mosquitoes including Coxiella, Yersinia, Xanthomonas, and Knoellia. The bacterial diversity per specimen was low ranging from 1 to 4. The results show the importance of pairing culture and fingerprint methods to better screen the bacterial community in Anopheles mosquitoes.Sampled Anopheles species from central-south Vietnam contained a diverse bacterial microbiota that needs to be investigated further in order to develop new malaria control approaches. The combination of both culture and DNA fingerprint methods allowed a thorough and complementary screening of the bacterial community in Anopheles mosquitoes.

  15. Bacterial Diversity Associated with Wild Caught Anopheles Mosquitoes from Dak Nong Province, Vietnam Using Culture and DNA Fingerprint

    Science.gov (United States)

    Ngo, Chung Thuy; Aujoulat, Fabien; Veas, Francisco; Jumas-Bilak, Estelle; Manguin, Sylvie

    2015-01-01

    Background Microbiota of Anopheles midgut can modulate vector immunity and block Plasmodium development. Investigation on the bacterial biodiversity in Anopheles, and specifically on the identification of bacteria that might be used in malaria transmission blocking approaches, has been mainly conducted on malaria vectors of Africa. Vietnam is an endemic country for both malaria and Bancroftian filariasis whose parasitic agents can be transmitted by the same Anopheles species. No information on the microbiota of Anopheles mosquitoes in Vietnam was available previous to this study. Method The culture dependent approach, using different mediums, and culture independent (16S rRNA PCR – TTGE) method were used to investigate the bacterial biodiversity in the abdomen of 5 Anopheles species collected from Dak Nong Province, central-south Vietnam. Molecular methods, sequencing and phylogenetic analysis were used to characterize the microbiota. Results and Discussion The microbiota in wild-caught Anopheles was diverse with the presence of 47 bacterial OTUs belonging to 30 genera, including bacterial genera impacting Plasmodium development. The bacteria were affiliated with 4 phyla, Actinobacteria, Bacteroidetes, Firmicutes and Proteobacteria, the latter being the dominant phylum. Four bacterial genera are newly described in Anopheles mosquitoes including Coxiella, Yersinia, Xanthomonas, and Knoellia. The bacterial diversity per specimen was low ranging from 1 to 4. The results show the importance of pairing culture and fingerprint methods to better screen the bacterial community in Anopheles mosquitoes. Conclusion Sampled Anopheles species from central-south Vietnam contained a diverse bacterial microbiota that needs to be investigated further in order to develop new malaria control approaches. The combination of both culture and DNA fingerprint methods allowed a thorough and complementary screening of the bacterial community in Anopheles mosquitoes. PMID:25747513

  16. Inactivation of Anopheles gambiae Glutathione Transferase ε2 by Epiphyllocoumarin

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    Patience Marimo

    2016-01-01

    Full Text Available Glutathione transferases (GSTs are part of a major family of detoxifying enzymes that can catalyze the reductive dehydrochlorination of dichlorodiphenyltrichloroethane (DDT. The delta and epsilon classes of insect GSTs have been implicated in conferring resistance to this insecticide. In this study, the inactivation of Anopheles gambiae GSTε2 by epiphyllocoumarin (Tral 1 was investigated. Recombinant AgGSTε2 was expressed in Escherichia coli cells containing a pET3a-AGSTε2 plasmid and purified by affinity chromatography. Tral 1 was shown to inactivate GSTε2 both in a time-dependent manner and in a concentration-dependent manner. The half-life of GSTε2 in the presence of 25 μM ethacrynic acid (ETA was 22 minutes and with Tral 1 was 30 minutes, indicating that Tral 1 was not as efficient as ETA as an inactivator. The inactivation parameters kinact and KI were found to be 0.020 ± 0.001 min−1 and 7.5 ± 2.1 μM, respectively, after 90 minutes of incubation. Inactivation of GSTε2 by Tral 1 implies that Tral 1 covalently binds to this enzyme in vitro and would be expected to exhibit time-dependent effects on the enzyme in vivo. Tral 1, therefore, would produce irreversible effects when used together with dichlorodiphenyltrichloroethane (DDT in malaria control programmes where resistance is mediated by GSTs.

  17. TEMPAT PERKEMBANGBIAKAN ANOPHELES ACONITUS DI KABUPATEN JEPARA, JAWA TENGAH

    Directory of Open Access Journals (Sweden)

    Mardiana Mardiana

    2012-10-01

    Full Text Available Kabupaten Jepara adalah salah satu kabupaten endemis malaria di Jawa Tengah. Kasus malaria di Kabupaten Jepara terjadi akibat interaksi antara nyamuk/vektor, parasit, lingkungan dan manusia yang mengalami perubahan dari waktu ke waktu. Penelitian tempat perkembangbiakan vektor malaria Anopheles aconitus dilakukan di Desa Buaran, Kecamatan Mayong, Kabupaten Jepara, Jawa Tengah pada tahun 2000. Tujuan penelitian mengetahui pengaruh perubahan lingkungan alami dan perubahan buatan oleh manusia terhadap tempat perkembangbiakan An. aconitus. Metode penelitian dengan cara pengumpulan larva dan pupa yang dilakukan pada pagi hari dengan menggunakan cidukan di tempat-tempat genangan air yang diduga sebagai tempat perkembangbiakan An. aconitus Dari hasil pengambilan jentik di sawah, saluran irigasi, sungai dan lubang/kobakan bekas  galian pasir yang digenangi air, ternyata yang banyak ditemukan adalah jentik An. aconitus dari 6 spesies jentik nyamuk yang teridentifikasi. Habitat utama An. aconitus di Kabupaten Jepara adalah persawahan. Perubahan habitat terjadi dengan adanya perubahan lingkungan dan musim, dimana pada musim kemarau sebagian sawah menjadi kering, sehingga mempengaruhi peril'aku nyamuk  untuk mencari habitat yang baru seperti  sungai  dan  saluran irigasi. Selain perubahan musim juga adanya lubang/kobakan yang digenangan air bekas galian pasir di sepanjang tepi sungai, sebagai akibat perbuatan dari penduduk setempat, sehingga menjadi habitat baru dari nyamuk terutama An.aconitus. Kata Kunci : Tempat Perkembangbiakan, An. aconitus, Malaria,

  18. The role of hemocytes in Anopheles gambiae antiplasmodial immunity.

    Science.gov (United States)

    Ramirez, Jose Luis; Garver, Lindsey S; Brayner, Fábio André; Alves, Luiz Carlos; Rodrigues, Janneth; Molina-Cruz, Alvaro; Barillas-Mury, Carolina

    2014-01-01

    Hemocytes synthesize key components of the mosquito complement-like system, but their role in the activation of antiplasmodial responses has not been established. The effect of activating Toll signaling in hemocytes on Plasmodium survival was investigated by transferring hemocytes or cell-free hemolymph from donor mosquitoes in which the suppressor cactus was silenced. These transfers greatly enhanced antiplasmodial immunity, indicating that hemocytes are active players in the activation of the complement-like system, through an effector/effectors regulated by the Toll pathway. A comparative analysis of hemocyte populations between susceptible G3 and the refractory L3-5 Anopheles gambiae mosquito strains did not reveal significant differences under basal conditions or in response to Plasmodium berghei infection. The response of susceptible mosquitoes to different Plasmodium species revealed similar kinetics following infection with P. berghei,P. yoelii or P. falciparum, but the strength of the priming response was stronger in less compatible mosquito-parasite pairs. The Toll, Imd,STAT or JNK signaling cascades were not essential for the production of the hemocyte differentiation factor (HDF) in response to P. berghei infection, but disruption of Toll, STAT or JNK abolished hemocyte differentiation in response to HDF. We conclude that hemocytes are key mediators of A. gambiae antiplasmodial responses. PMID:23886925

  19. Observaciones sobre Phlebotomus y Anopheles en el Callejon de Huaylas

    Directory of Open Access Journals (Sweden)

    Arístides Herrer

    1943-03-01

    Full Text Available Se han llevado a cabo observaciones entomológicas en relación con la verruga y el paludismo en la zona del Callejón de Huaylas comprendida desde la ciudad de Yuramarca a la de Huarás, prestando especial atención a la región del Cañón del Pato. Se indica, como resultados de tales observaciones, la presencia de las titiras: Phlebotomus verrucarum, P. peruensis, P. noguchii y una especia nueva, señalando detenidamente las localidades donde se las han encontrado. El P. verrucarum, principal trasmisor de la verruga, se halla a lo largo de toda la zona estudiada, siendo su número bastante reducido en la ciudad de Huarás. Desde Yuramarca hasta cerca de la ciudad de Carás se ha encontrado únicamente el Anopheles pseudopunctipennis, tanto larvas como adultos. Sus criaderos se encuentran principalmente en las márgenes del río Santa, en las de algunos afluentes de éste y en numerosos, manantiales.

  20. Innate immunity against malaria parasites in Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    Yang Chenand; Zhi-Hui Weng; Liangbiao Zheng

    2008-01-01

    Malaria continues to exert a huge toll in the world today, causing approximately 400 million cases and killing between 1-2 million people annually. Most of the malaria burden is borne by countries in Africa. For this reason, the major vector for malaria in this continent, Anopheles gambiae, is under intense study. With the completion of the draft sequence of this important vector, efforts are underway to develop novel control strategies.One promising area is to harness the power of the innate immunity of this mosquito species to block the transmission of the malaria parasites. Recent studies have demonstrated that Toll and Imd signaling pathways and other immunity-related genes (encoding proteins possibly function in recognition or as effector molecules) play significant roles in two different arms of innate immunity: level of infection intensity and melanization of Plasmodium oocysts.The challenges in the future are to understand how the functions of these different genes are coordinated in defense against malaria parasites, and if different arms of innate immunity are cross-regulated or coordinated.

  1. Transcriptome analysis of Anopheles stephensi embryo using expressed sequence tags

    Indian Academy of Sciences (India)

    Kaustubh Gokhale; Deepak P Patil; Dhiraj P Dhotre; Rajnikant Dixit; Murlidhar J Mendki; Milind S Patole; Yogesh S Shouche

    2013-06-01

    Germ band retraction (GBR) stage is one of the important stages during insect development. It is associated with an extensive epithelial morphogenesis and may also be pivotal in generation of morphological diversity in insects. Despite its importance, only a handful of studies report the transcriptome repertoire of this stage in insects. Here, we report generation, annotation and analysis of ESTs from the embryonic stage (16–22 h post fertilization) of laboratory-reared Anopheles stephensi mosquitoes. A total of 1002 contigs were obtained upon clustering of 1140 high-quality ESTs, which demonstrates an astonishingly low transcript redundancy (12.1%). Putative functions were assigned only to 213 contigs (21%), comprising mainly of transcripts encoding protein synthesis machinery. Approximately 78% of the transcripts remain uncharacterized, illustrating a lack of sequence information about the genes expressed in the embryonic stages of mosquitoes. This study highlights several novel transcripts, which apart from insect development, may significantly contribute to the essential biological complexity underlying insect viability in adverse environments. Nonetheless, the generated sequence information from this work provides a comprehensive resource for genome annotation, microarray development, phylogenetic analysis and other molecular biology applications in entomology.

  2. Determinants of Anopheles seasonal distribution patterns across a forest to periurban gradient near Iquitos, Peru.

    Science.gov (United States)

    Reinbold-Wasson, Drew D; Sardelis, Michael R; Jones, James W; Watts, Douglas M; Fernandez, Roberto; Carbajal, Faustino; Pecor, James E; Calampa, Carlos; Klein, Terry A; Turell, Michael J

    2012-03-01

    As part of a field ecology study of arbovirus and malaria activity in the Amazon Basin, Loreto Department, Peru, we collected mosquitoes landing on humans at a forest site and inside and outside of residences and military barracks at periurban, rural, and village sites. We collected 11 Anopheles spp. from these four sites. An. darlingi, the principal malaria vector in the region, accounted for 98.7% of all Anopheles spp. collected at Puerto Almendra. Peaks in landing activity occurred during the December and April collection periods. However, the percent of sporozoite-positive Anopheles spp. was highest 1-2 months later, when landing activity decreased to approximately 10% of the peak activity periods. At all sites, peak landing activity occurred about 2 hours after sunset. These data provide a better understanding of the taxonomy, population density, and seasonal and habitat distribution of potential malaria vectors within the Amazon Basin region.

  3. FAUNA DAN TEMPAT PERKEMBANGBIAKAN POTENSIAL NYAMUK Anopheles spp DI KECAMATAN MAYONG, KABUPATEN JEPARA, JAWA TENGAH

    Directory of Open Access Journals (Sweden)

    Mardiana Mardiana

    2012-10-01

    Full Text Available Malaria masih merupakan masalah kesehatan masyarakat di beberapa daerah pedesaan di Jawa Tengah. Usaha pemberantasan malaria telah dilakukan oleh program baik secara kimiawi maupun hayati, guna memutuskan rantai penularan. Penelitian fauna dan tempat perindukan potensial nyamuk Anopheles telah dilakukan di Desa Buaran, Kecamatan Mayong I, Kabupaten Jepara, Jawa Tengah. Penangkapan nyamuk dengan umpan orang dilakukan di dalam dan di luar rumah pada malam hari dari pukul 18.00-24.00 yang masing-masing dilakukan oleh dua orang kolektor. Penangkapan nyamuk yang istirahat di dalam dan luar rumah (vegetasi pada pagi hari dilakukan pukul 06.00-08.00, yang dilakukan satu bulan 4 kali penangkapan selama 6 bulan. Pengambilan larva dan pupa dilakukan dari pukul 06.00-08.00 pagi di tempat genangan air dan sawah serta tempat yang potensial diduga sebagai perindukan Anopheles. Hasil penangkapan selama 6 bulan, diperoleh 1248 ekor nyamuk Anopheles yang terdiri dari 6 spesies yaitu: An. aconitus 442 ekor (35,42%, An. annularis 69 ekor (5,53% , An. barbirostris 30 ekor (2,4%, An. maculatus 2 ekor (0,16%, An. tesselatus 5 ekor (0,40% dan An. vagus 700 ekor (56,09%. Populasi aconitus ditemukan dari penangkapan di luar rumah, pada bulan Juli (56,40%, Agustus (42,80% dan Oktober (39,50% sedangkan pada bulan Mei (52,9%, Juni (44% dan September (50,40% dari penangkapan di kandang sapi. Pengambilan larva dan pupa Anopheles dilakukan di tempat habitat seperti sawah yang pada bulan Aguslus terbanyak ditemukan sebesar 85 (1.70, di sungai ditemukan hanya 4 (0.08 serta di genangan air bekas telapak kaki/kobokan ditemukan sebesar 6 (0.12. Ternyata tempat perindukan yang potensial larva Anopheles pada musim kemarau, ditemukan pada sungai yang ditanami kangkung oleh masyarakat selempat. Kata kunci: Fauna, tempat perindukan, Anopheles, vector

  4. Field evaluation of deet against Anopheles farauti at Ndendo (Santa Cruz) Island, Solomon Islands.

    Science.gov (United States)

    Frances, S P; Bugoro, H; Butafa, C; Cooper, R D

    2010-09-01

    Field efficacy studies comparing two formulations of deet (N,N-diethyl-3-methylbenzamide) against mosquitoes were conducted on Ndendo Island, Solomon Islands. The repellent study was conducted at Pala village in November 2008, and the only mosquito species collected was Anopheles farauti Laveran. A formulation containing 35% deet in a gel provided >95% protection for 2 h, whereas a formulation containing 40% deet in ethanol in a spray applicator provided >95% for only 1 h. This field study demonstrated again that repellents containing deet provide a relatively short period of complete protection against Anopheles spp. PMID:20939380

  5. Molecular identification of a myosuppressin receptor from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Schöller, Susanne; Belmont, Martin; Cazzamali, Giuseppe;

    2005-01-01

    The insect myosuppressins (X1DVX2HX3FLRFamide) are neuropeptides that generally block insect muscle activities. We have used the genomic sequence information from the malaria mosquito Anopheles gambiae Genome Project to clone a G protein-coupled receptor that was closely related to the two...... previously cloned and characterized myosuppressin receptors from Drosophila [Proc. Natl. Acad. Sci. USA 100 (2003) 9808]. The mosquito receptor cDNA was expressed in Chinese hamster ovary cells and was found to be activated by low concentrations of Anopheles myosuppressin (TDVDHVFLRFamide; EC50, 1.6 x 10...... identification of a mosquito neuropeptide receptor....

  6. Paridade de Anopheles cruzii em Floresta Ombrófila Densa no Sul do Brasil Anopheles cruzii parity in dense rain forest in Southern Brazil

    Directory of Open Access Journals (Sweden)

    Ana Caroline Dalla Bona

    2006-12-01

    Full Text Available OBJETIVO: Conhecer a paridade e desenvolvimento ovariano da espécie Anopheles cruzii, durante os períodos estacionais. MÉTODOS: As capturas foram realizadas quinzenalmente, no período matutino, de abril/2004 a abril/2005, no Parque Estadual do Palmito, município de Paranaguá litoral do Estado do Paraná. Mosquitos adultos foram capturados usando a técnica pouso homem. As dissecções foram feitas utilizando-se a técnica de Detinova e de Polovodova e a avaliação do desenvolvimento folicular, segundo os critérios de Christophers e Mer. RESULTADOS: Foram dissecadas 208 fêmeas de Anopheles cruzii. A maioria das fêmeas dissecadas nas estações eram nulíparas. Sendo que 14,4% eram nulíparas com folículo além do estádio II de Christophers & Mer, o que evidencia o exercício da hematofagia previamente à primeira oviposição. Observou-se que as populações de Anopheles cruzii são constituídas de indivíduos jovens, talvez em razão da alta mortalidade de fêmeas paridas. CONCLUSÕES: A provável discordância gonotrófica das fêmeas dissecadas é importante do ponto de vista epidemiológico, considerando que a fêmea pode procurar mais de um hospedeiro para completar a maturação dos seus ovos.OBJECTIVE: To determine the parity and ovarian development of Anopheles cruzii species during the seasons. METHODS: Collections were carried out fortnightly in the morning in the Palmito State Park in the municipality of Paranaguá, Southern Brazil, between April 2004 and April 2005. Adult mosquitoes were captured using human landing rate. Dissections were performed using Detinova's and Polovodova's methods and follicular development was assessed following Christophers and Mer's criteria. RESULTS: A total of 208 specimens of Anopheles cruzii were dissected. Most females dissected were nulliparous in the seasons; 14.4% of them were found to be nulliparous above Christophers and Mer's stage II, which shows previous blood meal prior to the

  7. Ecology of mosquitoes (Diptera: Culicidae in areas of Serra do Mar State Park, State of São Paulo, Brazil. II - Habitat distribution

    Directory of Open Access Journals (Sweden)

    Anthony Érico Guimarães

    2000-01-01

    Full Text Available The mosquito (Diptera: Culicidae ecology was studied in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized biweekly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992. A total of 24,943 adult mosquitoes belonging to 57 species were collected during 622 collective periods. Aedes scapularis, Coquillettidia chrysonotum, Cq. venezuelensis, Wyeomyia dyari, Wy. longirostris, Wy. theobaldi and Wy. palmata were more frequently collected at swampy and at flooded areas. Anopheles mediopunctatus, Culex nigripalpus, Ae. serratus, Ae. fulvus, Psorophora ferox, Ps. albipes and the Sabethini in general, were captured almost exclusively in forested areas. An. cruzii, An. oswaldoi and An. fluminensis were captured more frequently in a residence area. However, Cx. quinquefasciatus was the only one truly eusynanthropic. An. cruzii and Ae. scapularis were captured feeding on blood inside and around the residence, indicating that both species, malaria and arbovirus vectors respectively, may be involved in the transmission of these such diseases in rural areas.

  8. Biodiversity and influence of climatic factors on mosquitoes (Diptera: Culicidae) around the Peixe Angical hydroelectric scheme in the state of Tocantins, Brazil.

    Science.gov (United States)

    Silva, Júlia Dos Santos; Pacheco, Juliana Barreto; Alencar, Jeronimo; Guimarães, Anthony Erico

    2010-03-01

    The influence of climatic factors on the seasonal frequency of mosquitoes (Diptera: Culicidae) at the Peixe Angical hydroelectric scheme (Tocantins, Brazil) was evaluated in the present paper. Mosquito surveys were conducted in the municipality of Peixe and in areas surrounding the reservoir in the municipalities of Paranã and São Salvador do Tocantins during two daytime periods (10 am-12 noon and 2 pm-4 pm) and two night-time periods (6 pm-8 pm and 6 pm-10 am) over 14 months. In total, 10,840 specimens from 42 species were captured, 84.5% of which belonged to the Culcinae. The most common species were Anopheles darlingi, Psorophora albipes and Sabethes chloropterus. The number of Culicidae specimens was higher in months with higher rainfall and air humidity than during the drier months. The large population of Ps. albipes and the presence of both An. darlingi (primary vector for human malaria parasites) and Haemagogus janthinomys (primary vector for yellow fever virus) are highlighted.

  9. Comparison of fatty acid contents and composition in major lipid classes of larvae and adults of mosquitoes (Diptera: Culicidae) from a steppe region.

    Science.gov (United States)

    Sushchik, Nadezhda N; Yurchenko, Yuri A; Gladyshev, Michail I; Belevich, Olga E; Kalachova, Galina S; Kolmakova, Angelika A

    2013-10-01

    Emerging aquatic insects, including mosquitoes, are known to transfer to terrestrial ecosystems specific essential biochemicals, such as polyunsaturated fatty acids (PUFA). We studied fatty acid (FA) composition and contents of dominant mosquito populations (Diptera: Culicidae), that is, Anopheles messeae, Ochlerotatus caspius, Oc. flavescens, Oc. euedes, Oc. subdiversus, Oc. cataphylla, and Aedes cinereus, inhabited a steppe wetland of a temperate climate zone to fill up the gap in their lipid knowledge. The polar lipid and triacylglycerol fractions of larvae and adults were compared. In most studied mosquito species, we first found and identified a number of short-chain PUFA, for example, prominent 14:2n-6 and 14:3n-3, which were not earlier documented in living organisms. These PUFA, although occurred in low levels in adult mosquitoes, can be potentially used as markers of mosquito biomass in terrestrial food webs. We hypothesize that these acids might be synthesized (or retroconverted) by the mosquitoes. Using FA trophic markers accumulated in triacylglycerols, trophic relations of the mosquitoes were accessed. The larval diet comprised green algae, cryptophytes, and dinoflagellates and provided the mosquitoes with essential n-3 PUFA, linolenic, and eicosapentaenoic acids. As a result, both larvae and adults of the studied mosquitoes had comparatively high content of the essential PUFA. Comparison of FA proportions in polar lipids versus storage lipids shown that during mosquito metamorphosis transfer of essential eicosapentaenoic and arachidonic acids from the reserve in storage lipids of larvae to functional polar lipids in adults occurred.

  10. Mosquito repellent attracts Culicoides imicola (Diptera: Ceratopogonidae).

    Science.gov (United States)

    Braverman, Y; Chizov-Ginzburg, A; Mullens, B A

    1999-01-01

    A plant-derived mosquito repellent, based on the oil of Eucalyptus maculata var. citriodora Hook, was evaluated against the biting midge Culicoides imicola Kieffer. Suction black light-traps covered with repellent-impregnated polyester mesh and deployed near horses attracted large numbers of C. imicola, which were seen near the treated net within a few minutes of the start of the experiment. Initial collections in the traps were approximately 3 times as large as those in control traps with untreated mesh. Numbers collected in treated traps were similar to untreated control traps after 4 h. Traps with mesh treated with DEET or another plant-derived (Meliaceae) proprietary product, AG1000, acted as repellents relative to the control. The differential activity of repellents against blood-feeding Diptera is discussed. PMID:10071502

  11. Rehydration of forensically important larval Diptera specimens.

    Science.gov (United States)

    Sanford, Michelle R; Pechal, Jennifer L; Tomberlin, Jeffery K

    2011-01-01

    Established procedures for collecting and preserving evidence are essential for all forensic disciplines to be accepted in court and by the forensic community at large. Entomological evidence, such as Diptera larvae, are primarily preserved in ethanol, which can evaporate over time, resulting in the dehydration of specimens. In this study, methods used for rehydrating specimens were compared. The changes in larval specimens with respect to larval length and weight for three forensically important blow fly (Diptera: Calliphoridae) species in North America were quantified. Phormia regina (Meigen), Cochliomyia macellaria (F.), and Chrysomya rufifacies (Macquart) third-instar larvae were collected from various decomposing animals and preserved with three preservation methods (80% ethanol, 70% isopropyl alcohol, and hot-water kill then 80% ethanol). Preservative solutions were allowed to evaporate. Rehydration was attempted with either of the following: 80% ethanol, commercial trisodium phosphate substitute solution, or 0.5% trisodium phosphate solution. All three methods partially restored weight and length of specimens recorded before preservation. Analysis of variance results indicated that effects of preservation, rehydration treatment, and collection animal were different in each species. The interaction between preservative method and rehydration treatment had a significant effect on both P. regina and C. macellaria larval length and weight. In addition, there was a significant interaction effect of collection animal on larval C. macellaria measurements. No significant effect was observed in C. rufifacies larval length or weight among the preservatives or treatments. These methods could be used to establish a standard operating procedure for dealing with dehydrated larval specimens in forensic investigations.

  12. A High-Affinity Adenosine Kinase from Anopheles Gambiae

    Energy Technology Data Exchange (ETDEWEB)

    M Cassera; M Ho; E Merino; E Burgos; A Rinaldo-Matthis; S Almo; V Schramm

    2011-12-31

    Genome analysis revealed a mosquito orthologue of adenosine kinase in Anopheles gambiae (AgAK; the most important vector for the transmission of Plasmodium falciparum in Africa). P. falciparum are purine auxotrophs and do not express an adenosine kinase but rely on their hosts for purines. AgAK was kinetically characterized and found to have the highest affinity for adenosine (K{sub m} = 8.1 nM) of any known adenosine kinase. AgAK is specific for adenosine at the nucleoside site, but several nucleotide triphosphate phosphoryl donors are tolerated. The AgAK crystal structure with a bound bisubstrate analogue Ap{sub 4}A (2.0 {angstrom} resolution) reveals interactions for adenosine and ATP and the geometry for phosphoryl transfer. The polyphosphate charge is partly neutralized by a bound Mg{sup 2+} ion and an ion pair to a catalytic site Arg. The AgAK structure consists of a large catalytic core in a three-layer {alpha}/{beta}/{alpha} sandwich, and a small cap domain in contact with adenosine. The specificity and tight binding for adenosine arise from hydrogen bond interactions of Asn14, Leu16, Leu40, Leu133, Leu168, Phe168, and Thr171 and the backbone of Ile39 and Phe168 with the adenine ring as well as through hydrogen bond interactions between Asp18, Gly64, and Asn68 and the ribosyl 2'- and 3'-hydroxyl groups. The structure is more similar to that of human adenosine kinase (48% identical) than to that of AK from Toxoplasma gondii (31% identical). With this extraordinary affinity for AgAK, adenosine is efficiently captured and converted to AMP at near the diffusion limit, suggesting an important role for this enzyme in the maintenance of the adenine nucleotide pool. mRNA analysis verifies that AgAK transcripts are produced in the adult insects.

  13. Unexpected high losses of Anopheles gambiae larvae due to rainfall.

    Directory of Open Access Journals (Sweden)

    Krijn P Paaijmans

    Full Text Available BACKGROUND: Immature stages of the malaria mosquito Anopheles gambiae experience high mortality, but its cause is poorly understood. Here we study the impact of rainfall, one of the abiotic factors to which the immatures are frequently exposed, on their mortality. METHODOLOGY/PRINCIPAL FINDINGS: We show that rainfall significantly affected larval mosquitoes by flushing them out of their aquatic habitat and killing them. Outdoor experiments under natural conditions in Kenya revealed that the additional nightly loss of larvae caused by rainfall was on average 17.5% for the youngest (L1 larvae and 4.8% for the oldest (L4 larvae; an additional 10.5% (increase from 0.9 to 11.4% of the L1 larvae and 3.3% (from 0.1 to 3.4% of the L4 larvae were flushed away and larval mortality increased by 6.9% (from 4.6 to 11.5% and 1.5% (from 4.1 to 5.6% for L1 and L4 larvae, respectively, compared to nights without rain. On rainy nights, 1.3% and 0.7% of L1 and L4 larvae, respectively, were lost due to ejection from the breeding site. CONCLUSIONS/SIGNIFICANCE: This study demonstrates that immature populations of malaria mosquitoes suffer high losses during rainfall events. As these populations are likely to experience several rain showers during their lifespan, rainfall will have a profound effect on the productivity of mosquito breeding sites and, as a result, on the transmission of malaria. These findings are discussed in the light of malaria risk and changing rainfall patterns in response to climate change.

  14. Chloroquine mediated modulation of Anopheles gambiae gene expression.

    Directory of Open Access Journals (Sweden)

    Patrícia Abrantes

    Full Text Available BACKGROUND: Plasmodium development in the mosquito is crucial for malaria transmission and depends on the parasite's interaction with a variety of cell types and specific mosquito factors that have both positive and negative effects on infection. Whereas the defensive response of the mosquito contributes to a decrease in parasite numbers during these stages, some components of the blood meal are known to favor infection, potentiating the risk of increased transmission. The presence of the antimalarial drug chloroquine in the mosquito's blood meal has been associated with an increase in Plasmodium infectivity for the mosquito, which is possibly caused by chloroquine interfering with the capacity of the mosquito to defend against the infection. METHODOLOGY/PRINCIPAL FINDINGS: In this study, we report a detailed survey of the Anopheles gambiae genes that are differentially regulated by the presence of chloroquine in the blood meal, using an A. gambiae cDNA microarray. The effect of chloroquine on transcript abundance was evaluated separately for non-infected and Plasmodium berghei-infected mosquitoes. Chloroquine was found to affect the abundance of transcripts that encode proteins involved in a variety of processes, including immunity, apoptosis, cytoskeleton and the response to oxidative stress. This pattern of differential gene expression may explain the weakened mosquito defense response which accounts for the increased infectivity observed in chloroquine-treated mosquitoes. CONCLUSIONS/SIGNIFICANCE: The results of the present study suggest that chloroquine can interfere with several putative mosquito mechanisms of defense against Plasmodium at the level of gene expression and highlight the need for a better understanding of the impacts of antimalarial agents on parasite transmission.

  15. Systematics and Population Level Analysis of Anopheles darlingi

    Directory of Open Access Journals (Sweden)

    Conn JE

    1998-01-01

    Full Text Available A new phylogenetic analysis of the Nyssorhynchus subgenus (Danoff-Burg and Conn, unpub. data using six data sets {morphological (all life stages; scanning electron micrographs of eggs; nuclear ITS2 sequences; mitochondrial COII, ND2 and ND6 sequences} revealed different topologies when each data set was analyzed separately but no heterogeneity between the data sets using the arn test. Consequently, the most accurate estimate of the phylogeny was obtained when all the data were combined. This new phylogeny supports a monophyletic Nyssorhynchus subgenus but both previously recognized sections in the subgenus (Albimanus and Argyritarsis were demonstrated to be paraphyletic relative to each other and four of the seven clades included species previously placed in both sections. One of these clades includes both Anopheles darlingi and An. albimanus, suggesting that the ability to vector malaria effectively may have originated once in this subgenus. Both a conserved (315 bp and a variable (425 bp region of the mitochondrial COI gene from 15 populations of An. darlingi from Belize, Bolivia, Brazil, French Guiana, Peru and Venezuela were used to examine the evolutionary history of this species and to test several analytical assumptions. Results demonstrated (1 parsimony analysis is equally informative compared to distance analysis using NJ; (2 clades or clusters are more strongly supported when these two regions are combined compared to either region separately; (3 evidence (in the form of remnants of older haplotype lineages for two colonization events; and (4 significant genetic divergence within the population from Peixoto de Azevedo (State of Mato Grosso, Brazil. The oldest lineage includes populations from Peixoto, Boa Vista (State of Roraima and Dourado (State of São Paulo.

  16. Pteridine fluorescence for age determination of Anopheles mosquitoes.

    Science.gov (United States)

    Wu, D; Lehane, M J

    1999-02-01

    The age structure of mosquito populations is of great relevance to understanding the dynamics of disease transmission and in monitoring the success of control operations. Unfortunately, the ovarian dissection methods currently available for determining the age of adult mosquitoes are technically difficult, slow and may be of limited value, because the proportion of diagnostic ovarioles in the ovary declines with age. By means of reversed-phase HPLC this study investigated the malaria vectors Anopheles gambiae and An. stephensi to see if changes in fluorescent pteridine pigments, which have been used in other insects to determine the age of field-caught individuals, may be useful for age determination in mosquitoes. Whole body fluorescence was inversely proportional to age (P 91%) up to 30 days postemergence, with the regression values: y = 40580-706x for An. gambiae, and y = 52896-681x for An. stephensi. In both species the main pteridines were 6-biopterin, pterin-6-carboxylic acid and an unidentified fluorescent compound. An. gambiae had only 50-70% as much fluorescence as An. stephensi, and fluorescent compounds were relatively more concentrated in the head than in the thorax (ratios 1:0.8 An. gambiae; 1:0.5 An. stephensi). The results of this laboratory study are encouraging. It seems feasible that this simpler and faster technique of fluorescence quantification could yield results of equivalent accuracy to the interpretation of ovarian dissection. A double-blind field trial comparing the accuracy of this technique to marked, released and recaptured mosquitoes is required to test the usefulness of the pteridine method in the field. PMID:10194749

  17. The Anopheles dirus complex: spatial distribution and environmental drivers

    Directory of Open Access Journals (Sweden)

    Defourny Pierre

    2007-03-01

    Full Text Available Abstract Background The Anopheles dirus complex includes efficient malaria vectors of the Asian forested zone. Studies suggest ecological and biological differences between the species of the complex but variations within species suggest possible environmental influences. Behavioural variation might determine vector capacity and adaptation to changing environment. It is thus necessary to clarify the species distributions and the influences of environment on behavioural heterogeneity. Methods A literature review highlights variation between species, influences of environmental drivers, and consequences on vector status and control. The localisation of collection sites from the literature and from a recent project (MALVECASIA produces detailed species distributions maps. These facilitate species identification and analysis of environmental influences. Results The maps give a good overview of species distributions. If species status partly explains behavioural heterogeneity, occurrence and vectorial status, some environmental drivers have at least the same importance. Those include rainfall, temperature, humidity, shade, soil type, water chemistry and moon phase. Most factors are probably constantly favourable in forest. Biological specificities, behaviour and high human-vector contact in the forest can explain the association of this complex with high malaria prevalence, multi-drug resistant Plasmodium falciparum and partial control failure of forest malaria in Southeast Asia. Conclusion Environmental and human factors seem better than species specificities at explaining behavioural heterogeneity. Although forest seems essential for mosquito survival, adaptations to orchards and wells have been recorded. Understanding the relationship between landscape components and mosquito population is a priority in foreseeing the influence of land-cover changes on malaria occurrence and in shaping control strategies for the future.

  18. Breeding of Anopheles mosquitoes in irrigated areas of South Punjab, Pakistan

    DEFF Research Database (Denmark)

    Herrel, N; Amerasinghe, F P; Ensink, J;

    2001-01-01

    As part of investigations on potential linkages between irrigation and malaria transmission, all surface water bodies in and around three villages along an irrigation distributary in South Punjab, Pakistan, were surveyed for anopheline mosquito larvae (Diptera: Culicidae) from April 1999 to March...

  19. Larvicidal effects of a neem (Azadirachta indica) oil formulation on the malaria vector Anopheles gambiae

    NARCIS (Netherlands)

    Okumu, F.O.; Knols, B.G.J.; Fillinger, U.

    2007-01-01

    Background - Larviciding is a key strategy used in many vector control programmes around the world. Costs could be reduced if larvicides could be manufactured locally. The potential of natural products as larvicides against the main African malaria vector, Anopheles gambiae s.s was evaluated. Method

  20. Improvement of a synthetic lure for Anopheles gambiae using compounds produced by human skin microbiota

    NARCIS (Netherlands)

    Verhulst, N.O.; Mbadi, P.A.; Bukovinszkine-Kiss, G.; Mukabana, W.R.; Loon, van J.J.A.; Takken, W.; Smallegange, R.C.

    2011-01-01

    Background - Anopheles gambiae sensu stricto is considered to be highly anthropophilic and volatiles of human origin provide essential cues during its host-seeking behaviour. A synthetic blend of three human-derived volatiles, ammonia, lactic acid and tetradecanoic acid, attracts A. gambiae. In addi

  1. Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin

    NARCIS (Netherlands)

    N'Guessan, R.; Boko, P.; Odjo, A.; Knols, B.G.J.; Akogbeto, M.; Rowland, M.

    2009-01-01

    Objective To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Method Eight-week trial conducted in experimental

  2. Olfaction in the malaria mosquito Anopheles gambiae : Electrophysiology and identification of kairomones

    NARCIS (Netherlands)

    Meijerink, J.

    1999-01-01

    Female mosquitoes of the species Anopheles gambiae Giles sensu stricto are important vectors of human malaria in Africa. It is generally assumed that they locate their human host by odours. These odours are detected by olfactory receptor neurons situated within cuticular extensions on the antenna. T

  3. Inhibition of host-seeking response and olfactory responsiveness in Anopheles gambiae following blood feeding

    NARCIS (Netherlands)

    Takken, W.; Loon, van J.J.A.; Adam, W.

    2001-01-01

    The effect of a single blood meal on the host-seeking response of Anopheles gambiae was investigated in the laboratory using a behavioural bioassay, whereas possible changes at the chemosensory level were monitored using electroantennogram recording (EAG). To avoid the possible confounding effect of

  4. Ecology of Anopheles stephensi in a malarious area, southeast of Iran.

    Science.gov (United States)

    Mehravaran, Ahmad; Vatandoost, Hassan; Oshaghi, Mohammad Ali; Abai, Mohammad Reza; Edalat, Hamideh; Javadian, Ezatoddin; Mashayekhi, Minoo; Piazak, Norair; Hanafi-Bojd, Ahmad Ali

    2012-01-01

    District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropophilic index and egg morphological characteristics. Anthropophilicity index was assessed by ELISA test. Activity of Anopheles species started at the beginning of April, and its peak occurs in late spring. The larvae were found in the river bed with pools, stagnant streams, slow foothill streams, temporary pools, and slowly moving water with and without vegetation, drainage containers of air conditioner and palm irrigation canals. From different methods of adult collection, it was found that spray sheet collection is the appropriate method. ELISA testing of 144 blood meals of females revealed the anthropophilicity of 11.8% indicating host preference on animal, mainly cow. Ridge length and their number on the egg floats confirmed Anopheles stephensi mysorensis form. This study showed that Anopheles stephensi is the main vector of malaria in the region, although some other species may play a role. Our findings could provide a valuable clue for epidemiology and control of malaria in the southeast of Iran. PMID:22267381

  5. Tyrosine Hydroxylase is crucial for maintaining pupal tanning and immunity in Anopheles sinensis.

    Science.gov (United States)

    Qiao, Liang; Du, Minghui; Liang, Xin; Hao, Youjin; He, Xiu; Si, Fengling; Mei, Ting; Chen, Bin

    2016-01-01

    Tyrosine hydroxylase (TH), the initial enzyme in the melanin pathway, catalyzes tyrosine conversion into Dopa. Although expression and regulation of TH have been shown to affect cuticle pigmentation in insects, no direct functional studies to date have focused on the specific physiological processes involving the enzyme during mosquito development. In the current study, silencing of AsTH during the time period of continuous high expression in Anopheles sinensis pupae led to significant impairment of cuticle tanning and thickness, imposing a severe obstacle to eclosion in adults. Meanwhile, deficiency of melanin in interference individuals led to suppression of melanization, compared to control individuals. Consequently, the ability to defend exogenous microorganisms declined sharply. Accompanying down-regulation of the basal expression of five antimicrobial peptide genes resulted in further significant weakening of immunity. TH homologs as well as the composition of upstream transcription factor binding sites at the pupal stage are highly conserved in the Anopheles genus, implying that the TH-mediated functions are crucial in Anopheles. The collective evidence strongly suggests that TH is essential for Anopheles pupae tanning and immunity and provides a reference for further studies to validate the utility of the key genes involved in the melanization pathway in controlling mosquito development. PMID:27416870

  6. Behavioural response of the malaria vector Anopheles gambiae to host plant volatiles and synthetic blends

    Science.gov (United States)

    Sugar feeding is critical for survival of malaria vectors and, although discriminative plant feeding previously has been shown to occur in Anopheles gambiae s.s., little is known about the cues mediating attraction to these plants. In this study, we investigated the role of olfaction in An. gambiae ...

  7. New selenoproteins identified in silico from the genome of Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    JIANG Liang; LIU Qiong; CHEN Ping; GAO ZhongHong; XU HuiBi

    2007-01-01

    Selenoprotein is biosynthesized by the incorporation of selenocysteine into proteins, where the TGA codon in the open reading frame does not act as a stop signal but is translated into selenocysteine. The dual functions of TGA result in mis-annotation or lack of selenoproteins in the sequenced genomes of many species. Available computational tools fail to correctly predict selenoproteins. Thus, we developed a new method to identify selenoproteins from the genome of Anopheles gambiae computationally.Based on released genomic information, several programs were edited with PERL language to identify selenocysteine insertion sequence (SECIS) element, the coding potential of TGA codons, and cysteine-containing homologs of selenoprotein genes. Our results showed that 11365 genes were terminated with TGA codons, 918 of which contained SECIS elements. Similarity search revealed that 58genes contained Sec/Cys pairs and similar flanking regions around in-frame TGA codons. Finally, 7genes were found to fully meet requirements for selenoproteins, although they have not been annotated as selenoproteins in NCBI databases. Deduced from their basic properties, the newly found selenoproteins in the genome of Anopheles gambiae are possibly related to in vivo oxidation tolerance and protein regulation in order to interfere with anopheles' vectorial capacity of Plasmodium. This study may also provide theoretical bases for the prevention of malaria from anopheles transmission.

  8. Effect of larval crowding on mating competitiveness of Anopheles gambiae mosquitoes

    NARCIS (Netherlands)

    Ng'habi, K.R.; John, B.; Nkwengulila, G.; Knols, B.G.J.; Killeen, G.F.; Ferguson, H.M.

    2005-01-01

    Background: The success of sterile or transgenic Anopheles for malaria control depends on their mating competitiveness within wild populations. Current evidence suggests that transgenic mosquitoes have reduced fitness. One means of compensating for this fitness deficit would be to identify environme

  9. Ecology of Anopheles Stephensi in a Malarious Area, Southeast of Iran

    Directory of Open Access Journals (Sweden)

    Norair Piazak

    2012-01-01

    Full Text Available District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropophilic index and egg morphological characteristics. Anthropophilicity index was assessed by ELISA test. Activity of Anopheles species started at the beginning of April, and its peak occurs in late spring. The larvae were found in the river bed with pools, stagnant streams, slow foothill streams, temporary pools, and slowly moving water with and without vegetation, drainage containers of air conditioner and palm irrigation canals. From different methods of adult collection, it was found that spray sheet collection is the appropriate method. ELISA testing of 144 blood meals of females revealed the anthropophilicity of 11.8% indicating host preference on animal, mainly cow. Ridge length and their number on the egg floats confirmed Anopheles stephensi mysorensis form. This study showed that Anopheles stephensi is the main vector of malaria in the region, although some other species may play a role. Our findings could provide a valuable clue for epidemiology and control of malaria in the southeast of Iran.

  10. Using a near-infrared spectrometer to estimate the age of anopheles mosquitoes exposed to pyrethroids.

    Directory of Open Access Journals (Sweden)

    Maggy T Sikulu

    Full Text Available We report on the accuracy of using near-infrared spectroscopy (NIRS to predict the age of Anopheles mosquitoes reared from wild larvae and a mixed age-wild adult population collected from pit traps after exposure to pyrethroids. The mosquitoes reared from wild larvae were estimated as <7 or ≥7 d old with an overall accuracy of 79%. The age categories of Anopheles mosquitoes that were not exposed to the insecticide papers were predicted with 78% accuracy whereas the age categories of resistant, susceptible and mosquitoes exposed to control papers were predicted with 82%, 78% and 79% accuracy, respectively. The ages of 85% of the wild-collected mixed-age Anopheles were predicted by NIRS as ≤8 d for both susceptible and resistant groups. The age structure of wild-collected mosquitoes was not significantly different for the pyrethroid-susceptible and pyrethroid-resistant mosquitoes (P = 0.210. Based on these findings, NIRS chronological age estimation technique for Anopheles mosquitoes may be independent of insecticide exposure and the environmental conditions to which the mosquitoes are exposed.

  11. Species-specific chemosensory gene expression in the olfactory organs of the malaria vector Anopheles gambiae

    NARCIS (Netherlands)

    Hodges, Theresa K.; Cosme, Luciano V.; Athrey, Giridhar; Pathikonda, Sharmila; Takken, Willem; Slotman, Michel A.

    2014-01-01

    Background: The malaria mosquito Anopheles gambiae has a high preference for human hosts, a characteristic that contributes greatly to its capacity for transmitting human malaria. A sibling species, An. quadriannulatus, has a quite different host preference and feeds mostly on bovids. For this re

  12. Was Anopheles donaldi a vector of malaria in Kuala Lumpur, Malaysia, in the past?

    Science.gov (United States)

    Reid, J A

    1980-01-01

    Anopheles donaldi Reid, a member of the A. barbirostris species group, is a vector of human filariasis and probably malaria. The discovery of some old specimens of this species, collected in Kuala Lumpur town where it no longer occurs, together with evidence from the literature about past malaria in the town, suggest that donaldi may have played a part in transmitting that malaria.

  13. Sharing of antigens between Plasmodium falciparum and Anopheles albimanus Antígenos compartidos entre Plasmodium falciparum y Anopheles albimanus

    Directory of Open Access Journals (Sweden)

    Albina Wide

    2006-12-01

    Full Text Available The presence of common antigens between Plasmodium falciparum and Anopheles albimanus was demonstrated. Different groups of rabbits were immunized with: crude extract from female An. albimanus (EAaF, red blood cells infected with Plasmodium falciparum (EPfs, and the SPf66 synthetic malaria vaccine. The rabbit's polyclonal antibodies were evaluated by ELISA, Multiple Antigen Blot Assay (MABA, and immunoblotting. All extracts were immunogenic in rabbits according to these three techniques, when they were evaluated against the homologous antigens. Ten molecules were identified in female mosquitoes and also in P. falciparum antigens by the autologous sera. The electrophoretic pattern by SDS-PAGE was different for the three antigens evaluated. Cross-reactions between An. albimanus and P. falciparum were found by ELISA, MABA, and immunoblotting. Anti-P. falciparum and anti-SPf66 antibodies recognized ten and five components in the EAaF crude extract, respectively. Likewise, immune sera against female An. albimanus identified four molecules in the P. falciparum extract antigen. As far as we know, this is the first work that demonstrates shared antigens between anophelines and malaria parasites. This finding could be useful for diagnosis, vaccines, and the study of physiology of the immune response to malaria.Epítopes de antígenos compartidos entre Plasmodium falciparum y Anopheles albimanus fueron identificados. Diferentes grupos de conejos fueron inmunizados con: extracto crudo de mosquito hembra de An. albimanus (EAaH, glóbulos rojos infectados con P. falciparum (EPfs y la vacuna antimalárica sintética SPf66. Los anticuerpos policlonales producidos en conejos fueron evaluados por ELISA, inmunoensayo simultáneo de múltiples antígenos (MABA e Immunoblotting. Todos los extractos resultaron inmunogénicos cuando se evaluaron por ELISA, MABA e Immunoblotting. Diez moléculas fueron identificadas en los mosquitos hembras y diez en los antígenos de

  14. A new species of Culcua Walker (Diptera: Stratiomyidae) from Vietnam

    Science.gov (United States)

    A new species of Culcua Walker (Diptera: Stratiomyidae), C. lingafelteri Woodley, new species, is described from northern Vietnam. It is diagnosed relative to other species using the recent revision of the genus by Rozkošný and Kozánek (2007). This is the first species of Culcua reported from Viet...

  15. De wapenvlieg Clitellaria ephippium terug van weggeweest (Diptera: Stratiomyidae)

    OpenAIRE

    Korf, W.; Leij, van der, A.

    2000-01-01

    Clitellaria ephippium, rediscovered in the Netherlands after 100 years (Diptera: Stratiomyidae) Clitellaria ephippium has been found in the Netherlands only between 1870 and 1880 near Venlo. In 1999 a female of this beautifully coloured fly was caught near Tegelen. This locality is very close to the first site, in the northern part of the province of Limburg.

  16. Development of Rhagoletis indifferens Curran (Diptera:Tephritidae) in crabapple

    Science.gov (United States)

    Western cherry fruit fly, Rhagoletis indifferens, Curran, 1932 (Diptera: Tephritidae), was reared from naturally-infested Chinese crabapple, Malus spectabilis (Ait.) Borkh. (Rosaceae), in Washington state, U.S.A. Pupae from Chinese crabapple were smaller than those from sweet cherry, Prunus avium (...

  17. Checklist of the family Simuliidae (Diptera of Finland

    Directory of Open Access Journals (Sweden)

    Jari Ilmonen

    2014-09-01

    Full Text Available A checklist of the family Simuliidae (Diptera is provided for Finland and recognizes 56 species. One new record has been added (Simulium latipes and one name sunken in synonymy (Simulium carpathicum. Furthermore, Simulium tsheburovae is treated as a doubtful record.

  18. Scanning electron microscopy of the male genitalia of Sarcophagidae (Diptera

    Directory of Open Access Journals (Sweden)

    Hugo de Souza Lopes

    1990-03-01

    Full Text Available The male genitalia of nine species of Sarcophagidae (Diptera - Goniophyto honsuensis Rohdendorf, 1962, Tricharaea brevicornis (Wiedemann, 1830, Chaetoravinia derelicta (Walker, 1852, Austrohartigia spinigena (Rondani, 1864, Chrysagria duodecimpunctata Townsend, 1935, Boettcheria bisetosa Parker, 1914, Lipoptilocnema lanei Townsend, 1934, L. crispina (Lopes, 1938 and Euboettcheria alvarengai Lopes & Tibana, 1982 - were examined by scanning electron microscope (SEM and the main morphological features are descirbed.

  19. West African Anopheles gambiae mosquitoes harbor a taxonomically diverse virome including new insect-specific flaviviruses, mononegaviruses, and totiviruses.

    Science.gov (United States)

    Fauver, Joseph R; Grubaugh, Nathan D; Krajacich, Benjamin J; Weger-Lucarelli, James; Lakin, Steven M; Fakoli, Lawrence S; Bolay, Fatorma K; Diclaro, Joseph W; Dabiré, Kounbobr Roch; Foy, Brian D; Brackney, Doug E; Ebel, Gregory D; Stenglein, Mark D

    2016-11-01

    Anopheles gambiae are a major vector of malaria in sub-Saharan Africa. Viruses that naturally infect these mosquitoes may impact their physiology and ability to transmit pathogens. We therefore used metagenomics sequencing to search for viruses in adult Anopheles mosquitoes collected from Liberia, Senegal, and Burkina Faso. We identified a number of virus and virus-like sequences from mosquito midgut contents, including 14 coding-complete genome segments and 26 partial sequences. The coding-complete sequences define new viruses in the order Mononegavirales, and the families Flaviviridae, and Totiviridae. The identification of a flavivirus infecting Anopheles mosquitoes broadens our understanding of the evolution and host range of this virus family. This study increases our understanding of virus diversity in general, begins to define the virome of a medically important vector in its natural setting, and lays groundwork for future studies examining the potential impact of these viruses on anopheles biology and disease transmission. PMID:27639161

  20. Anofelinos de Santa Catarina (Diptera: Culicidae, Brasil Anophelines of Santa Catarina (Diptera: Culicidae, Brazil

    Directory of Open Access Journals (Sweden)

    Maria da Graça Teixeira Portes

    2010-04-01

    Full Text Available INTRODUÇÃO: No Brasil, a Região Amazônica é endêmica em malária. Em Santa Catarina, a malária foi eliminada na década de 80. A partir daí, ocorreram poucos casos autóctones isolados, e esporádicos. No entanto, em função da existência do vetor em seu território, da existência de extensa área endêmica no Brasil e da grande mobilidade de pessoas em áreas turísticas no estado, existe a probabilidade de reintrodução da doença. MÉTODOS: Utilizou-se os seguintes dados: Banco de Dados do Núcleo de Entomologia da Fundação Nacional de Saúde, Santa Catarina (ACCES,1997-2000; Sistema de Informação de Vigilância Epidemiológica, Secretaria de Vigilância em Saúde (Malária/SC e Sistema de Informação de Notificação e Agravo(SINAN/SC. Os mesmos foram transportados e analisados, no programa Microsoft Office Excel 2007. RESULTADOS: As coletas foram realizadas em 48 municípios, 159 localidades, sendo identificados 12.310 Culicídeos, 11.546 (93,7% Anopheles e 764 (6,2% como outros. Foram identificados três subgêneros e 13 espécies de anofelinos. CONCLUSÕES: Considerando que nos municípios pesquisados, foi identificada a presença de importantes vetores como Anopheles cruzii e Anopheles albitasis e há circulação de pessoas infectadas provenientes de áreas endêmicas, pode-se considerar que os mesmos são áreas receptivas e vulneráveis à malária. Essas espécies são suspeitas de serem responsáveis pela transmissão de malária na região, principalmente nos municípios de Gaspar, Indaial e Rodeio.INTRODUCTION: The Amazon region of Brazil is endemic for malaria. In the State of Santa Catarina, malaria was eliminated in the 1980s. Since then, a few sporadic isolated autochthonous cases have occurred. However, because malaria vectors are present within Brazilian territory and extensive endemic areas exist in this country, along with the great mobility of people in tourist areas of Santa Catarina, there is the

  1. A simplified high-throughput method for pyrethroid knock-down resistance (kdr) detection in Anopheles gambiae

    OpenAIRE

    Walker Edward D; Black William C; Randle Nadine P; McCall P J; Ranson Hilary; Lynd Amy; Donnelly Martin J

    2005-01-01

    Abstract Background A single base pair mutation in the sodium channel confers knock-down resistance to pyrethroids in many insect species. Its occurrence in Anopheles mosquitoes may have important implications for malaria vector control especially considering the current trend for large scale pyrethroid-treated bednet programmes. Screening Anopheles gambiae populations for the kdr mutation has become one of the mainstays of programmes that monitor the development of insecticide resistance. Th...

  2. KOMPETENSI VEKTORIAL Anopheles maculatus, Theobald di KECAMATAN KOKAP, KABUPATEN KULONPROGO

    Directory of Open Access Journals (Sweden)

    Umi Widyastuti

    2013-07-01

    Full Text Available Abstrak Malaria masih merupakan masalah kesehatan di Kabupaten Kulonprogo, khususnya di Kecamatan Kokap. Dalam dua tahun terakhir menunjukkan bahwa pada tahun 2009, 1 dari 5 desa di Kecamatan Kokap sebagai daerah malaria dengan statifikasi Insidensi Kasus Rendah (Low Case Incidence/LCI. Pada tahun 2010 meningkat menjadi 3 desa, peningkatan kasus malaria di Kecamatan Kokap berkaitan dengan keberadaan nyamuk Anopheles yang berpotensi sebagai vektor. Beberapa spesies seperti An. maculatus, An. aconitus, dan An. balabacensis diduga sebagai vektor malaria potensial di daerah ini. Penelitian ini bertujuan untuk mengetahui kompetensi vektorial An. maculatus yang terdiri dari: kerentanan nyamuk An. maculatus terhadap Plasmodium, sifat antropofilik, angka paritas, dan kepadatan nyamuk. Kerentanan nyamuk terhadap Plasmodium diukur dengan deteksi antigen protein sporozoit (Circum Sporozoite Protein/CSP dari P. falciparum atau P. vivax pada dada-kepala dari semua nyamuk parous. Karakteristik antropofilik diukur dengan mendeteksi darah manusia pada perut nyamuk dengan kondisi penuh darah dan setengah gravid. Kedua deteksi tersebut dilakukan dengan teknik ELISA. Penelitian dilakukan pada bulan Mei sampai Oktober 2011 di dua desa yaitu: Tegiri dan Gunungrego, Kecamatan Kokap. Nyamuk ditangkap dengan menggunakan metode sesuai dengan pedoman WHO. Penangkapan dilakukan pada malam hari (18.00-06.00 terhadap nyamuk yang hinggap pada manusia di dalam rumah, di luar rumah, nyamuk yang istirahat baik di dalam rumah (dinding maupun luar rumah (sekitar kandang ternak dan penangkapan pada pagi hari (06.00-08.00. Kepadatan An. maculatus dihitung dan paritas nyamuk ditentukan dengan pembedahan ovarium secara mikroskopis. Hasil penelitian menunjukkan bahwa An. maculatus di Gunungrego rentan terhadap P. vivax dengan angka sporozoit 3,57%. Namun, CSP antigen P. vivax tidak terdeteksi pada dada-kepala nyamuk An. maculatus dari Tegiri. Antigen CSP P. falciparum negatif pada

  3. Potential Test of Papaya Leaf and Seed Extract (Carica Papaya) as Larvicides against Anopheles Mosquito Larvae Mortality. SP IN Jayapura, Papua Indonesia

    OpenAIRE

    Arsunan

    2015-01-01

    Anopheles mosquitoes, sp is the main vector of malaria disease that is widespread in many parts of the world including in Papua Province. There are four speciesof Anopheles mosquitoes, sp, in Papua namely: An.farauti, An.koliensis, An. subpictus, and An.punctulatus. Larviciding synthetic cause resistance. This study aims to analyze the potential of papaya leaf and seeds extracts (Carica papaya) as larvicides against the mosquitoes Anopheles sp. The experiment was conducted at the Laboratory o...

  4. The role of reactive oxygen species on Plasmodium melanotic encapsulation in Anopheles gambiae.

    Science.gov (United States)

    Kumar, Sanjeev; Christophides, George K; Cantera, Rafael; Charles, Bradley; Han, Yeon Soo; Meister, Stephan; Dimopoulos, George; Kafatos, Fotis C; Barillas-Mury, Carolina

    2003-11-25

    Malaria transmission depends on the competence of some Anopheles mosquitoes to sustain Plasmodium development (susceptibility). A genetically selected refractory strain of Anopheles gambiae blocks Plasmodium development, melanizing, and encapsulating the parasite in a reaction that begins with tyrosine oxidation, and involves three quantitative trait loci. Morphological and microarray mRNA expression analysis suggest that the refractory and susceptible strains have broad physiological differences, which are related to the production and detoxification of reactive oxygen species. Physiological studies corroborate that the refractory strain is in a chronic state of oxidative stress, which is exacerbated by blood feeding, resulting in increased steady-state levels of reactive oxygen species, which favor melanization of parasites as well as Sephadex beads. PMID:14623973

  5. Integrated genetic map of Anopheles gambiae: use of RAPD polymorphisms for genetic, cytogenetic and STS landmarks.

    Science.gov (United States)

    Dimopoulos, G; Zheng, L; Kumar, V; della Torre, A; Kafatos, F C; Louis, C

    1996-06-01

    Randomly amplified polymorphic DNA (RAPD) markers have been integrated in the genetic and cytogenetic maps of the malaria vector mosquito, Anopheles gambiae. Fifteen of these markers were mapped by recombination, relative to microsatellite markers that had been mapped previously. Thirty-four gel-purified RAPD bands were cloned and sequenced, generating sequence tagged sites (STSs) that can be used as entry points to the A. gambiae genome. Thirty one of these STSs were localized on nurse cell polytene chromosomes through their unique hybridization signal in in situ hybridization experiments. Five STSs map close to the breakpoints of polymorphic inversions, which are notable features of the Anopheles genome. The usefulness and limitations of this integrated mosquito map are discussed. PMID:8725241

  6. Ecology of Anopheles Stephensi in a Malarious Area, Southeast of Iran

    OpenAIRE

    Norair Piazak; Minoo Mashayekhi; Ezatoddin Javadian; Hamideh Edalat; Mohammad Reza Abai; Mohammad Ali Oshaghi; Hassan Vatandoost; Ahmad Mehravaran; Ahmad Ali Hanafi-Bojd

    2012-01-01

    District of Jiroft is situated in south-east of Iran which is one of the malarious regions. Anopheles stephensi is considered as one of the main malaria vector in this region. Ecology of this species was studied in the area to understand its vector behavior for implementation of effective vector control measures. Different methods like total catch, pit shelter, night bite collection on human and animal, larval dipping methods were used for species identification, seasonal activity, anthropoph...

  7. Invasion of Wolbachia into Anopheles and Other Insect Germlines in an Ex vivo Organ Culture System

    OpenAIRE

    Hughes, Grant L.; Andrew D Pike; Ping Xue; Jason L Rasgon

    2012-01-01

    The common bacterial endosymbiont Wolbachia manipulates its host's reproduction to promote its own maternal transmission, and can interfere with pathogen development in many insects making it an attractive agent for the control of arthropod-borne disease. However, many important species, including Anopheles mosquitoes, are uninfected. Wolbachia can be artificially transferred between insects in the laboratory but this can be a laborious and sometimes fruitless process. We used a simple ex viv...

  8. Olfaction in the malaria mosquito Anopheles gambiae : Electrophysiology and identification of kairomones

    OpenAIRE

    Meijerink, J

    1999-01-01

    Female mosquitoes of the species Anopheles gambiae Giles sensu stricto are important vectors of human malaria in Africa. It is generally assumed that they locate their human host by odours. These odours are detected by olfactory receptor neurons situated within cuticular extensions on the antenna. These cuticular extensions, called sensilla, contain numerous pores through which the odours can enter the sensillum and reach the olfactory receptor neuron membrane. Despite the fact that these mos...

  9. Comparison of the functional features of the pump organs of Anopheles sinensis and Aedes togoi

    OpenAIRE

    Young-Ran Ha; Seung-Chul Lee; Seung-Jun Seo; Jeongeun Ryu; Dong-Kyu Lee; Sang-Joon Lee

    2015-01-01

    Mosquitoes act as vectors for severe tropical diseases. Mosquito-borne diseases are affected by various factors such as environmental conditions, host body susceptibility, and mosquito feeding behavior. Among these factors, feeding behavior is affected by the feeding pump system located inside the mosquito head and also depends on the species of mosquito. Therefore, the 3D morphological structures of the feeding pumps of Aedes togoi and Anopheles sinensis were comparatively investigated using...

  10. Rhodopsin coexpression in UV photoreceptors of Aedes aegypti and Anopheles gambiae mosquitoes

    OpenAIRE

    Hu, Xiaobang; Leming, Matthew T; Whaley, Michelle A.; O'Tousa, Joseph E.

    2014-01-01

    Differential rhodopsin gene expression within specialized R7 photoreceptor cells divides the retinas of Aedes aegypti and Anopheles gambiae mosquitoes into distinct domains. The two species express the rhodopsin orthologs Aaop8 and Agop8, respectively, in a large subset of these R7 photoreceptors that function as ultraviolet receptors. We show here that a divergent subfamily of mosquito rhodopsins, Aaop10 and Agop10, is coexpressed in these R7 photoreceptors. The properties of the A. aegypti ...

  11. Larvicidal Effects of a Neem (Azadirachta indica) Oil Formulation on the Malaria Vector Anopheles Gambiae.

    OpenAIRE

    Knols Bart GJ; Okumu Fredros O; Fillinger Ulrike

    2007-01-01

    Abstract Background Larviciding is a key strategy used in many vector control programmes around the world. Costs could be reduced if larvicides could be manufactured locally. The potential of natural products as larvicides against the main African malaria vector, Anopheles gambiae s.s was evaluated. Methods To assess the larvicidal efficacy of a neem (Azadirachta indica) oil formulation (azadirachtin content of 0.03% w/v) on An. gambiae s.s., larvae were exposed as third and fourth instars to...

  12. Anopheles gambiae mosquito isolated neurons : a new biological model for optimizing insecticide/repellent efficacy

    OpenAIRE

    Lavialle-Defaix, C.; Apaire-Marchais, V; Legros, C.; Pennetier, Cédric; Mohamed, A; P. Licznar; Corbel, Vincent; Lapied, B

    2011-01-01

    To understand better the mode of action of insecticides and repellents used in vector-borne diseases control, we developed a new biological model based on mosquito neurons isolated from adults Anopheles gambiae heads. This cellular model is well adapted to multidisciplinary approaches: electrophysiology, pharmacology, molecular biology and biochemical assays. Using RT-PCR, we demonstrated that isolated neurons express the nicotinic acetylcholine receptor subunit alpha 1 (Ag alpha 1 nAchR), tw...

  13. Extensive circadian and light regulation of the transcriptome in the malaria mosquito Anopheles gambiae

    OpenAIRE

    Rund, Samuel SC; James E. Gentile; Duffield, Giles E.

    2013-01-01

    Background Mosquitoes exhibit 24 hr rhythms in flight activity, feeding, reproduction and development. To better understand the molecular basis for these rhythms in the nocturnal malaria vector Anopheles gambiae, we have utilized microarray analysis on time-of-day specific collections of mosquitoes over 48 hr to explore the coregulation of gene expression rhythms by the circadian clock and light, and compare these with the 24 hr rhythmic gene expression in the diurnal Aedes aegypti dengue vec...

  14. Ecological Genomics of Anopheles gambiae Along a Latitudinal Cline: A Population-Resequencing Approach

    OpenAIRE

    Cheng, Changde; White, Bradley J.; Kamdem, Colince; Mockaitis, Keithanne; Costantini, Carlo; Matthew W Hahn; Besansky, Nora J

    2012-01-01

    The association between fitness-related phenotypic traits and an environmental gradient offers one of the best opportunities to study the interplay between natural selection and migration. In cases in which specific genetic variants also show such clinal patterns, it may be possible to uncover the mutations responsible for local adaptation. The malaria vector, Anopheles gambiae, is associated with a latitudinal cline in aridity in Cameroon; a large inversion on chromosome 2L of this mosquito ...

  15. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes

    OpenAIRE

    Martha L. Salas; Romero, Jackeline F.; Yesid Solarte; Victor Olano; Myriam A. Herrera; Sócrates Herrera

    1994-01-01

    The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per ...

  16. Insecticide susceptibility status of Aedes aegypti and Anopheles stephensi larvae against temephos in Delhi, India

    OpenAIRE

    Singh, R. K.; P.K.Mittal; Gaurav Kumar; Dhiman, R.C.

    2014-01-01

    Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortali...

  17. The Population Genomics of Trans-Specific Inversion Polymorphisms in Anopheles gambiae

    OpenAIRE

    White, Bradley J.; Cheng, Changde; Sangaré, Djibril; Lobo, Neil F.; Collins, Frank H.; Besansky, Nora J

    2009-01-01

    In the malaria mosquito Anopheles gambiae polymorphic chromosomal inversions may play an important role in adaptation to environmental variation. Recently, we used microarray-based divergence mapping combined with targeted resequencing to map nucleotide differentiation between alternative arrangements of the 2La inversion. Here, we applied the same technique to four different polymorphic inversions on the 2R chromosome of An. gambiae. Surprisingly, divergence was much lower between alternativ...

  18. Biochemical Characterization of Anopheles gambiae SRPN6, a Malaria Parasite Invasion Marker in Mosquitoes

    OpenAIRE

    Chunju An; Yasuaki Hiromasa; Xin Zhang; Scott Lovell; Michal Zolkiewski; John M Tomich; Kristin Michel

    2012-01-01

    Serine proteinase inhibitors of the serpin family are well known as negative regulators of hemostasis, thrombolysis and innate immune responses. Additionally, non-inhibitory serpins serve functions as chaperones, hormone transporters, or anti-angiogenic factors. In the African malaria mosquito, Anopheles gambiae s.s., at least three serpins (SRPNs) are implicated in the innate immune response against malaria parasites. Based on reverse genetic and cell biological analyses, AgSRPN6 limits para...

  19. The JNK Pathway Is a Key Mediator of Anopheles gambiae Antiplasmodial Immunity

    OpenAIRE

    Garver, Lindsey S.; de Almeida Oliveira, Giselle; Barillas-Mury, Carolina

    2013-01-01

    The innate immune system of Anopheles gambiae mosquitoes limits Plasmodium infection through multiple molecular mechanisms. For example, midgut invasion by the parasite triggers an epithelial nitration response that promotes activation of the complement-like system. We found that suppression of the JNK pathway, by silencing either Hep, JNK, Jun or Fos expression, greatly enhanced Plasmodium infection; while overactivating this cascade, by silencing the suppressor Puckered, had the opposite ef...

  20. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae

    OpenAIRE

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A.; Serhan, Charles N.; Ribeiro, Jose M.; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to ‘remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that t...

  1. A Peroxidase/Dual Oxidase System Modulates Midgut Epithelial Immunity in Anopheles gambiae

    OpenAIRE

    Kumar, Sanjeev; Molina-Cruz, Alvaro; Gupta, Lalita; Rodrigues, Janneth; Barillas-Mury, Carolina

    2010-01-01

    Extracellular matrices in diverse biological systems are crosslinked by dityrosine covalent bonds catalyzed by the peroxidase/oxidase system. We show that the Immunomodulatory Peroxidase (IMPer), an enzyme secreted by the mosquito Anopheles gambiae midgut, and dual oxidase (Duox) form a dityrosine network that decreases gut permeability to immune elicitors and protects the microbiota by preventing activation of epithelial immunity. It also provides a suitable environment for malaria parasites...

  2. The STAT pathway mediates late phase immunity against Plasmodium in the mosquito Anopheles gambiae

    OpenAIRE

    Gupta, Lalita; Molina-Cruz, Alvaro; Kumar, Sanjeev; Rodrigues, Janneth; Dixit, Rajnikant; Zamora, Rodolfo E.; Barillas-Mury, Carolina

    2009-01-01

    The STAT family of transcription factors activate expression of immune system genes in vertebrates. The ancestral STAT gene (AgSTAT-A) appears to have duplicated in the mosquito Anopheles gambiae, giving rise to a second intronless STAT gene (AgSTAT-B), which we show regulates AgSTAT-A expression in adult females. AgSTAT-A participates in the transcriptional activation of nitric oxide synthase (NOS) in response to bacterial and plasmodial infection. Activation of this pathway, however, is not...

  3. Genome expression analysis of Anopheles gambiae: Responses to injury, bacterial challenge, and malaria infection

    OpenAIRE

    Dimopoulos, George; Christophides, George K.; Meister, Stephan; SCHULTZ, JÖRG; White, Kevin P.; Barillas-Mury, Carolina; Kafatos, Fotis C.

    2002-01-01

    The complex gene expression responses of Anopheles gambiae to microbial and malaria challenges, injury, and oxidative stress (in the mosquito and/or a cultured cell line) were surveyed by using cDNA microarrays constructed from an EST-clone collection. The expression profiles were broadly subdivided into induced and down-regulated gene clusters. Gram+ and Gram− bacteria and microbial elicitors up-regulated a diverse set of genes, many belonging to the immunity class, and the response to malar...

  4. Imidacloprid and Thiamethoxam Induced Mutations in Internal Transcribed Spacer 2 (ITS2) of Anopheles stephensi

    OpenAIRE

    Bhinder, Preety; Chaudhry, Asha; Barna, Bhupinder; Kaur, Satvinderjeet

    2012-01-01

    The present article deals with the polymerase chain reaction (PCR)-based genotoxicity evaluation of neonicotinoid pesticides, imidacloprid and thiamethoxam, by using the genome of a mosquito Anopheles stephensi taken as an experimental model. After treatment of the second instar larvae with LC20 of the pesticides for 24 h, the induced nucleotide sequence variations in the internal transcribed spacer 2 (ITS2) of freshly hatched unfed control and treated individuals was studied from the sequenc...

  5. The impact of insecticides management linked with resistance expression in Anopheles spp. populations

    OpenAIRE

    Guilherme Liberato da Silva; Thiago Nunes Pereira; Noeli Juarez Ferla; Onilda Santos da Silva

    2016-01-01

    Abstract The resistance of some species of Anopheles to chemical insecticides is spreading quickly throughout the world and has hindered the actions of prevention and control of malaria. The main mechanism responsible for resistance in these insects appears to be the target site known as knock-down resistance (kdr), which causes mutations in the sodium channel. Even so, many countries have made significant progress in the prevention of malaria, focusing largely on vector control through long-...

  6. The role of cow urine in the oviposition site preference of culicine and Anopheles mosquitoes

    OpenAIRE

    Kweka Eliningaya J; Owino Eunice A; Mwang'onde Beda J; Mahande Aneth M; Nyindo Mramba; Mosha Franklin

    2011-01-01

    Abstract Background Chemical and behavioural ecology of mosquitoes plays an important role in the development of chemical cue based vector control. To date, studies available have focused on evaluating mosquito attractants and repellents of synthetic and human origins. This study, however, was aimed at seasonal evaluation of the efficiency of cow urine in producing oviposition cues to Anopheles gambiae s.l. and Culex quinquefasciatus in both laboratory and field conditions. Methods Ovipositio...

  7. Chemical composition and insecticidal activity of plant essential oils from Benin against Anopheles gambiae (Giles)

    OpenAIRE

    Bossou, Annick; Mangelinckx, Sven; Yedomonhan, Hounnankpon; Boko, Pelagie M; Akogbeto, Martin C; De Kimpe, Norbert; Avlessi, Felicien; Sohounhloue, Dominique CK

    2013-01-01

    Background Insecticide resistance in sub-Saharan Africa and especially in Benin is a major public health issue hindering the control of the malaria vectors. Each Anopheles species has developed a resistance to one or several classes of the insecticides currently in use in the field. Therefore, it is urgent to find alternative compounds to conquer the vector. In this study, the efficacies of essential oils of nine plant species, which are traditionally used to avoid mosquito bites in Benin, we...

  8. Robust and regulatory expression of defensin A gene driven by vitellogenin promoter in transgenic Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    CHEN XiaoGuang; ZHANG YaJing; ZHENG XueLi; WANG ChunMei

    2007-01-01

    The use of genetically modified mosquitoes to reduce or replace field populations is a new strategy to control mosquito-borne diseases. The precondition of the implementation of this strategy is the ability to manipulate the genome of mosquitoes and to induce specific expression of the effector molecules driven by a suitable promoter. The objective of this study is to evaluate the expression of defensin A gene of Anopheles sinensis under the control of a vitellogenin promoter in transgenic Anopheles stephensi. The regulatory region of Anopheles gambiae vitellogenin was cloned and subcloned into transfer vector pSLFa consisting of an expression cassette with defensin A coding sequence. Then, the expression cassette was transferred into transformation vector pBac[3xP3-DsRedafm] using Asc I digestion. The recombinant plasmid DNA of pBac[3xP3DsRed-AgVgT2-DefA] and helper plasmid DNA of phsp-pBac were micro-injected into embryos of An. stephensi. The positive transgenic mosquitoes were screened by observing specific red fluorescence in the eyes of G1 larvae. Southern blot analysis showed that a single-copy transgene integrated into the genome of An. stephensi. RT-PCR analysis showed that the defensin A gene expressed specifically in fat bodies of female mosquitoes after a blood meal. Interestingly, the mRNA of defensin A is more stable compared with that of the endogenous vitellogenin gene. After multiple blood meals, the expression of defensin A appeared as a reducible and non-cycling type, a crucial feature for its anti-pathogen effect. From data above, we concluded that the regulatory function of the Vg promoter and the expression of defensin A gene were relatively conserved in different species of anopheles mosquitoes. These molecules could be used as candidates in the development of genetically modified mosquitoes.

  9. Cloning and molecular characterization of two invertebrate-type lysozymes from Anopheles gambiae

    OpenAIRE

    Paskewitz, S M; Li, B.; Kajla, M. K.

    2008-01-01

    We sequenced and characterized two novel invertebrate-type lysozymes from the mosquito Anopheles gambiae. Alignment and phylogenetic analysis of these and a number of related insect proteins identified through bioinformatics strategies showed a high degree of conservation of this protein family throughout the Class Insecta. Expression profiles were examined for the two mosquito genes through semiquantitative and real-time PCR analysis. Lys i-1 transcripts were found in adult females in the fa...

  10. Larvicidal and pupicidal activity of spinosad against the malarial vector Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Kolanthasamy Prabhu; Kadarkarai Murugan; Arjunan Nareshkumar; Subramanian Bragadeeswaran

    2011-01-01

    Objective:To investigate the larvicidal and pupicidal activity of spinosad againstAnopheles stephensi Listen.Methods: Spinosad from the actinomycete,Saccharopolyspora spinosa was tested againstAnopheles stephensi at different concentrations (0.01, 0.02, 0.04, 0.06 and0.08ppm.), and against first to fourth instar larvae and pupae.Results: The larval mortality ranged from36.1±1.7 in (0.01 ppm) to 79.3±1.8 (0.08 ppm) the first instar larva. The LC50andLC90values of first, second, third and fourth instar larva were0.001, 0.031, 0.034, 0.036and0.0113, 0.102, 0.111, 0.113, respectively. The pupal mortality ranged from33.0±2.0 (0.01 ppm) to 80.0±0.9 (0.08 ppm). The LC50 andLC90values were0.028 and 0.1020, respectively. The reduction percentage ofAnopheles larvae was82.7%, 91.4% and96.0% after 24, 48, 72 hours, respectively, while more than80% reduction was observed after3 weeks.Conclusions:In the present study spinosad effectively caused mortality of mosquito larvae in both the laboratory and field trial. It is predicted that spinosad is likely to be an effective larvicide for treatment of mosquito breeding sites.

  11. Thermal behaviour of Anopheles stephensi in response to infection with malaria and fungal entomopathogens

    Directory of Open Access Journals (Sweden)

    Read Andrew F

    2009-04-01

    Full Text Available Abstract Background Temperature is a critical determinant of the development of malaria parasites in mosquitoes, and hence the geographic distribution of malaria risk, but little is known about the thermal preferences of Anopheles. A number of other insects modify their thermal behaviour in response to infection. These alterations can be beneficial for the insect or for the infectious agent. Given current interest in developing fungal biopesticides for control of mosquitoes, Anopheles stephensi were examined to test whether mosquitoes showed thermally-mediated behaviour in response to infection with fungal entomopathogens and the rodent malaria, Plasmodium yoelii. Methods Over two experiments, groups of An. stephensi were infected with one of three entomopathogenic fungi, and/or P. yoelii. Infected and uninfected mosquitoes were released on to a thermal gradient (14 – 38°C for "snapshot" assessments of thermal preference during the first five days post-infection. Mosquito survival was monitored for eight days and, where appropriate, oocyst prevalence and intensity was assessed. Results and conclusion Both infected and uninfected An. stephensi showed a non-random distribution on the gradient, indicating some capacity to behaviourally thermoregulate. However, chosen resting temperatures were not altered by any of the infections. There is thus no evidence that thermally-mediated behaviours play a role in determining malaria prevalence or that they will influence the performance of fungal biopesticides against adult Anopheles.

  12. [The Anopheles fauna and the transmission of human malaria in Kinshasa (Zaire)].

    Science.gov (United States)

    Karch, S; Asidi, N; Manzambi, Z M; Salaun, J J

    1992-01-01

    A longitudinal epidemiological study of malaria and its vectors was conducted in Kinshasa. 264 night-bite collections on human bait (1,056 man nights) and 384 collections of the house-resting fauna were carried out from April 1989 to October 1990. The anophelian fauna was identified and inventoried, 7 Anopheles species were found: Anopheles gambiae, An. funestus, An. paludis, An. hancocki, An. counstani, An. brunnipes, and An. nili. A single species, An. gambiae s. l. is responsible for the transmission of malaria, it represents 93.27% of the anopheline fauna. The average number of anophele bites man day was 16.28 bites/man/night, it varied between 1 b/m/n in urban area to 26.05 b/m/n in semi-rural area. The average of the sporozoite index for An. gambiae was 3.3%, but it varied from 0% in the urban area to 6.52% in the semi-rural area. The entomological inoculation rate (h) was 197 infective bites per year. This rate fluctuated from 1 infective bite each 128 nights in urban area to 1.7 infective night-bite in semi-rural area. Other epidemiological index were also determined: the level of daily survival rate (p = 8.75 days), the vectorial capacity of 17.97 and the Macdonald's stability 3.5 bites on man taken by a vector during its entire lifetime.

  13. New selenoproteins identified in silico from the genome of Anopheles gambiae

    Institute of Scientific and Technical Information of China (English)

    2007-01-01

    Selenoprotein is biosynthesized by the incorporation of selenocysteine into proteins,where the TGA codon in the open reading frame does not act as a stop signal but is translated into selenocysteine.The dual functions of TGA result in mis-annotation or lack of selenoproteins in the sequenced genomes of many species.Available computational tools fail to correctly predict selenoproteins.Thus,we devel-oped a new method to identify selenoproteins from the genome of Anopheles gambiae computationally.Based on released genomic information,several programs were edited with PERL language to identify selenocysteine insertion sequence(SECIS)element,the coding potential of TGA codons,and cys-teine-containing homologs of selenoprotein genes.Our results showed that 11365 genes were termi-nated with TGA codons,918 of which contained SECIS elements.Similarity search revealed that 58 genes contained Sec/Cys pairs and similar flanking regions around in-frame TGA codons.Finally,7 genes were found to fully meet requirements for selenoproteins,although they have not been anno-tated as selenoproteins in NCBI databases.Deduced from their basic properties,the newly found se-lenoproteins in the genome of Anopheles gambiae are possibly related to in vivo oxidation tolerance and protein regulation in order to interfere with anopheles’ vectorial capacity of Plasmodium.This study may also provide theoretical bases for the prevention of malaria from anopheles transmission.

  14. Observations on sporozoite detection in naturally infected sibling species of the Anopheles culicifacies complex and variant of Anopheles stephensi in India

    Indian Academy of Sciences (India)

    Susanta Kumar Ghosh; Satyanarayan Tiwari; Kamaraju Raghavendra; Tiruchinapalli Sundaraj; Aditya Prasad Dash

    2008-09-01

    Sporozoites were detected in naturally infected sibling species of the primary rural vector Anopheles culicifacies complex in two primary health centres (PHCs) and a variant of the urban vector Anopheles stephensi in Mangalore city, Karnataka, south India while carrying out malaria outbreak investigations from 1998–2006. Sibling species of An. culicifacies were identified based on the banding patterns on ovarian polytene chromosomes, and variants of An. stephensi were identified based on the number of ridges on the egg floats. Sporozoites were detected in the salivary glands by the dissection method. Of the total 334 salivary glands of An. culicifacies dissected, 17 (5.08%) were found to be positive for sporozoites. Of the 17 positive samples, 11 were suitable for sibling species analysis; 10 were species A (an efficient vector) and 1 was species B (a poor vector). Out of 46 An. stephensi dissected, one was sporozoite positive and belonged to the type form (an efficient vector). In malaria epidemiology this observation is useful for planning an effective vector control programme, because each sibling species/variant differs in host specificity, susceptibility to malarial parasites, breeding habitats and response to insecticides.

  15. Revisão de Euprepina Hull (Diptera, Bombyliidae, Bombyliinae) Revision of Euprepina Hull (Diptera, Bombyliidae, Bombyliinae)

    OpenAIRE

    Carlos José Einicker Lamas; Márcia Souto Couri

    1999-01-01

    Euprepina Hull, 1971 (Diptera, Bombyliidae, Bombyliinae) a neotropical genus with ten species is revised. Redescriptions of eight species were made: E. nuda Hull, 1971, E. amabilis (Wulp, 1881), E. beckeri Lamas & Couri, 1998, E. bicincta (Wiedemann, 1830), E. caminaria (Wiedemann, 1830), E. knutsoni Hull, 1971, E. maracajula Hull, 1971 and E. truxalia Hull, 1971, with illustrations of the types, male terminalia and spermathecae. Two synonymies - E. bicincta (Wiedemann, 1830), syn.: E. bicinc...

  16. Essays on the history of Brazilian dipterology: II. notices about Brazilian Diptera (17th century)

    OpenAIRE

    Nelson Papavero; Márcia Souto Couri

    2012-01-01

    Essays on the history of Brazilian dipterology. II. Notices about Brazilian Diptera (17th century). Notices from the Brazilian Diptera from the 17th century come mainly from two foreign invasions occurred in Brazil, the first one by the French in Maranhão and the second by the Dutch in northeastern Brazil. This paper includes reports of Fathers Claude d'Abbeville and Yves d'Evreux and from Piso and Marcgrave, the last two presenting the first illustrations of Brazilian Diptera. The paper also...

  17. Essays on the history of Brazilian dipterology: II. notices about Brazilian Diptera (17th century

    Directory of Open Access Journals (Sweden)

    Nelson Papavero

    2012-06-01

    Full Text Available Essays on the history of Brazilian dipterology. II. Notices about Brazilian Diptera (17th century. Notices from the Brazilian Diptera from the 17th century come mainly from two foreign invasions occurred in Brazil, the first one by the French in Maranhão and the second by the Dutch in northeastern Brazil. This paper includes reports of Fathers Claude d'Abbeville and Yves d'Evreux and from Piso and Marcgrave, the last two presenting the first illustrations of Brazilian Diptera. The paper also includes reports of Friar Laureano de la Cruz, Father João de Sotto Mayor and Maurício de Heriarte.

  18. Neem by-products in the fight against mosquito-borne diseases: Biotoxicity of neem cake fractions towards the rural malaria vector Anopheles culicifacies (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Balamurugan Chandramohan

    2016-06-01

    Conclusions: Overall, this study suggests that the methanolic fractions of neem cake may be considered as a new and cheap source of highly effective compounds against the rural malaria vector An. culicifacies.

  19. Chemical composition and larvicidal activity of essential oil of Cupressus arizonica E.L. Greene against malaria vector Anopheles stephensi Liston (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Mohammad Mehdi Sedaghat

    2011-01-01

    Full Text Available Background: Using botanical insecticides as an alternative biocontrol technique for vector control is considered by some scientists. Materials and Methods: Chemical composition of the essential oil was analyzed using gas chromatography-mass spectrometry (GC-MS. In addition, the mosquito larvicidal activity of leaf essential oil of Cupressus arizonica was investigated against fourth instar larvae of laboratory-reared An. stephensi according to the method of the World Health Organization. Results: Of 46 constituents in the oil, limonene (14.44%, umbellulone (13.25% and α-pinene (11% were determined as the main constituents. Cupressus arizonica volatile oil showed significant larvicidal activity against An. stephensi with LC 50 and LC 90 values 79.30 ppm and 238.89 ppm respectively. Clear dose-response relationships were established with the highest dose of 160 ppm essential oil with almost 100% mortality. Discussion: The results from this study revealed that C. arizonica essential oil could be considered as a natural larvicide against An. stephensi. However, the field evaluation of the formulation is necessary.

  20. Studies of Anopheles gambiae s.l (Diptera: Culicidae exhibiting different vectorial capacities in lymphatic filariasis transmission in the Gomoa district, Ghana

    Directory of Open Access Journals (Sweden)

    Amuzu Hilaria

    2010-09-01

    Full Text Available Abstract Background Two lymphatic filariasis endemic communities Mampong and Hwida in Ghana have been regularly monitored for impact on transmission after annual mass drug administration (MDA with albendazole and ivermectin. After six MDAs even though the ABR for Mampong was 55883/person/year and that of Hwida was 2494/person/year, they both had ATPs of 15.21 infective larvae/person/year. Interestingly the human microfilaraemia levels had reduced significantly from 14% to 0% at Mampong and 12% to 3% at Hwida. In an attempt to understand this anomaly, we collected mosquitoes over a 5-month period using human landing catches to determine the species composition, the number of cibarial teeth, the lengths and widths of the cibarium and the cibarial dome of the vector populations. Results Out of 2553 mosquitoes caught at Mampong, 42.6% were An. gambiae s.l. All 280 identified further by PCR were An. gambiae s.s (275 M and 5 S molecular forms. At Hwida, 112 mosquitoes were obtained; 67 (59.8% were An. gambiae s.l, comprised of 40 (59.7% An. melas, 24 (35.8% An. gambiae s.s (17 and 5 M and S molecular forms respectively and 3 (4.5% unidentified. The mean number of teeth for An. melas was 14.1 (median = 14, range = 12-15, An. gambiae s.s., 15.7 (median = 15, range = 13-19 M form 15.5 (median = 15 range = 13-19 and S form 16 (median = 16, range 15-17. The observed differences in teeth numbers were significantly different between An. melas and An. gambiae s.s (p = 0.004, and the M form (p = 0.032 and the S form (p = 0.002. Conclusions In this study, An. gambiae s.s was the main vector at Mampong and was found to possess significantly more cibarial teeth than An. melas, the principal vector at Hwida. We postulate that the different impact observed after 6 MDAs may be due to An. gambiae s.s exhibiting 'facilitation' at Mampong and at Hwida An. melas the main vector exhibits 'limitation'. Thus it may be necessary to compliment MDA with vector control to achieve interruption of transmission in areas where An. melas may exhibit limitation.

  1. Identification of a Bacillus thuringiensis Cry11Ba toxin-binding aminopeptidase from the mosquito, Anopheles quadrimaculatus

    Directory of Open Access Journals (Sweden)

    Abdullah Mohd

    2006-05-01

    Full Text Available Abstract Background Aminopeptidase N (APN type proteins isolated from several species of lepidopteran insects have been implicated as Bacillus thuringiensis (Bt toxin-binding proteins (receptors for Cry toxins. We examined brush border membrane vesicle (BBMV proteins from the mosquito Anopheles quadrimaculatus to determine if APNs from this organism would bind mosquitocidal Cry toxins that are active to it. Results A 100-kDa protein with APN activity (APNAnq 100 was isolated from the brush border membrane of Anopheles quadrimaculatus. Native state binding analysis by surface plasmon resonance shows that APNAnq 100 forms tight binding to a mosquitocidal Bt toxin, Cry11Ba, but not to Cry2Aa, Cry4Ba or Cry11Aa. Conclusion An aminopeptidase from Anopheles quadrimaculatus mosquitoes is a specific binding protein for Bacillus thuringiensis Cry11Ba.

  2. Description of Anopheles gabonensis, a new species potentially involved in rodent malaria transmission in Gabon, Central Africa.

    Science.gov (United States)

    Rahola, Nil; Makanga, Boris; Yangari, Patrick; Jiolle, Davy; Fontenille, Didier; Renaud, François; Ollomo, Benjamin; Ayala, Diego; Prugnolle, Franck; Paupy, Christophe

    2014-12-01

    The genus Anopheles includes mosquito vectors of human malaria and arboviruses. In sub-Saharan Africa, the anopheline fauna is rich of nearly 150 species, few of which are anthropophilic and capable of transmitting pathogens to humans. Some of the remaining species are found in forests far from human environments and are vectors of wildlife pathogens. The diversity and the biology of these species have yet to be fully described. As a contribution to furthering knowledge of sylvan Anophelinae, using morphological and molecular tools we describe a new Anopheles species collected in Gabon (Central Africa), which we have named Anopheles gabonensis n. sp. We also molecularly screened this species to detect infections by Plasmodium parasites. The results showed the species to have been infected by Plasmodium vinckei, a rodent parasite. We discuss the role of An. gabonensis n. sp. in the transmission of P. vinckei in the rainforest areas of Central Africa and its potential to transfer pathogens to humans.

  3. Review of Temephos Discriminating Concentration for Monitoring the Susceptibility of Anopheles labranchiae (Falleroni, 1926), Malaria Vector in Morocco

    OpenAIRE

    Chandre, F; Ameur, B; Herrak, T.; E. Adlaoui; Elkohli, M.; Faraj, C.

    2010-01-01

    In Morocco, the resistance monitoring of Anopheles labranchiae larvae to temephos is done using discriminating concentration of 0.125 mg, which is half of the WHO recommended dose for Anopheles. However, this dosage seemed to be too high to allow an early detection of the resistance and its revision was found necessary. The present study was carried out during May-June 2008 and 2009 in nine provinces from the north-west of the country. The aim was to determine the lethal concentrations LC100 ...

  4. Ecotope-Based Entomological Surveillance and Molecular Xenomonitoring of Multidrug Resistant Malaria Parasites in Anopheles Vectors

    Directory of Open Access Journals (Sweden)

    Prapa Sorosjinda-Nunthawarasilp

    2014-01-01

    Full Text Available The emergence and spread of multidrug resistant (MDR malaria caused by Plasmodium falciparum or Plasmodium vivax have become increasingly important in the Greater Mekong Subregion (GMS. MDR malaria is the heritable and hypermutable property of human malarial parasite populations that can decrease in vitro and in vivo susceptibility to proven antimalarial drugs as they exhibit dose-dependent drug resistance and delayed parasite clearance time in treated patients. MDR malaria risk situations reflect consequences of the national policy and strategy as this influences the ongoing national-level or subnational-level implementation of malaria control strategies in endemic GMS countries. Based on our experience along with current literature review, the design of ecotope-based entomological surveillance (EES and molecular xenomonitoring of MDR falciparum and vivax malaria parasites in Anopheles vectors is proposed to monitor infection pockets in transmission control areas of forest and forest fringe-related malaria, so as to bridge malaria landscape ecology (ecotope and ecotone and epidemiology. Malaria ecotope and ecotone are confined to a malaria transmission area geographically associated with the infestation of Anopheles vectors and particular environments to which human activities are related. This enables the EES to encompass mosquito collection and identification, salivary gland DNA extraction, Plasmodium- and species-specific identification, molecular marker-based PCR detection methods for putative drug resistance genes, and data management. The EES establishes strong evidence of Anopheles vectors carrying MDR P. vivax in infection pockets epidemiologically linked with other data obtained during which a course of follow-up treatment of the notified P. vivax patients receiving the first-line treatment was conducted. For regional and global perspectives, the EES would augment the epidemiological surveillance and monitoring of MDR falciparum and

  5. PCR detection of malaria parasites in desiccated Anopheles mosquitoes is uninhibited by storage time and temperature

    Directory of Open Access Journals (Sweden)

    Rider Mark A

    2012-06-01

    Full Text Available Abstract Background Reliable methods to preserve mosquito vectors for malaria studies are necessary for detecting Plasmodium parasites. In field settings, however, maintaining a cold chain of storage from the time of collection until laboratory processing, or accessing other reliable means of sample preservation is often logistically impractical or cost prohibitive. As the Plasmodium infection rate of Anopheles mosquitoes is a central component of the entomological inoculation rate and other indicators of transmission intensity, storage conditions that affect pathogen detection may bias malaria surveillance indicators. This study investigated the effect of storage time and temperature on the ability to detect Plasmodium parasites in desiccated Anopheles mosquitoes by real-time polymerase chain reaction (PCR. Methods Laboratory-infected Anopheles stephensi mosquitoes were chloroform-killed and stored over desiccant for 0, 1, 3, and 6 months while being held at four different temperatures: 28, 37, -20 and -80°C. The detection of Plasmodium DNA was evaluated by real-time PCR amplification of a 111 base pair region of block 4 of the merozoite surface protein. Results Varying the storage time and temperature of desiccated mosquitoes did not impact the sensitivity of parasite detection. A two-way factorial analysis of variance suggested that storage time and temperature were not associated with a loss in the ability to detect parasites. Storage of samples at 28°C resulted in a significant increase in the ability to detect parasite DNA, though no other positive associations were observed between the experimental storage treatments and PCR amplification. Conclusions Cold chain maintenance of desiccated mosquito samples is not necessary for real-time PCR detection of parasite DNA. Though field-collected mosquitoes may be subjected to variable conditions prior to molecular processing, the storage of samples over an inexpensive and logistically

  6. Cardiocladius oliffi (Diptera: Chironomidae as a potential biological control agent against Simulium squamosum (Diptera: Simuliidae

    Directory of Open Access Journals (Sweden)

    Wilson Michael D

    2009-04-01

    Full Text Available Abstract Background The control of onchocerciasis in the African region is currently based mainly on the mass drug administration of ivermectin. Whilst this has been found to limit morbidity, it does not stop transmission. In the absence of a macrofilaricide, there is a need for an integrated approach for disease management, which includes vector control. Vector control using chemical insecticides is expensive to apply, and therefore the use of other measures such as biological control agents is needed. Immature stages of Simulium squamosum, reared in the laboratory from egg masses collected from the field at Boti Falls and Huhunya (River Pawnpawn in Ghana, were observed to be attacked and fed upon by larvae of the chironomid Cardiocladius oliffi Freeman, 1956 (Diptera: Chironomidae. Methods Cardiocladius oliffi was successfully reared in the rearing system developed for S. damnosum s.l. and evaluated for its importance as a biological control agent in the laboratory. Results Even at a ratio of one C. oliffi to five S. squamosum, they caused a significant decrease in the number of adult S. squamosum emerging from the systems (treatments. Predation was confirmed by the amplification of Simulium DNA from C. oliffi observed to have fed on S. squamosum pupae. The study also established that the chironomid flies could successfully complete their development on a fish food diet only. Conclusion Cardiocladius oliffi has been demonstrated as potential biological control agent against S. squamosum.

  7. Larvicidal activity of extracts from three Plumbago spp against Anopheles gambiae

    OpenAIRE

    Barasa M Maniafu; Lwande Wilber; Ndiege, Isaiah O.; Cornelius C Wanjala; Teresa Ayuko Akenga

    2009-01-01

    Three Plumbago spp have been tested for mosquito larvicidal activity. The crude extracts exhibiting the highest larvicidal activity against Anopheles gambiae were hexane (LC50 = 6.4 μg/mL) and chloroform (LC50 = 6.7 μg/mL) extracts from Plumbago zeylanica Linn, chloroform (LC50 = 6.7 ug/mL) extract from Plumbago stenophylla Bull and ethyl acetate (LC50 = 4.1 μg/mL) extract from Plumbago dawei Rolfe. These LC50 values were within 95% confidence limits. 5-hydroxy-2-methyl-1,4-nap...

  8. Effect of ivermectin on the larvae of Anopheles gambiae and Culex quinquefasciatus

    DEFF Research Database (Denmark)

    Derua, Yahya A.; Malongo, Bernard B.; Simonsen, Paul E.

    2016-01-01

    Background: Ivermectin is used extensively globally for treatment of helminthic and ectoparasitic infections in animals and humans. The effect of excreted ivermectin on non-target organisms in aquatic and terrestrial environments has been increasingly reported. Due to its low water solubility...... and adsorption to sediments, the ivermectin exposure-risk to aquatic organisms dwelling in different strata of water bodies varies. This study assessed the survival of larvae of Anopheles gambiae Giles and Culex quinquefasciatus Say, when exposed to low concentrations of ivermectin under laboratory conditions...

  9. Bionomics of the malaria vector Anopheles farauti in Temotu Province, Solomon Islands: issues for malaria elimination

    Directory of Open Access Journals (Sweden)

    Mackenzie Donna O

    2011-05-01

    Full Text Available Abstract Background In the Solomon Islands, the Malaria Eradication Programmes of the 1970s virtually eliminated the malaria vectors: Anopheles punctulatus and Anopheles koliensis, both late night biting, endophagic species. However, the vector, Anopheles farauti, changed its behaviour to bite early in the evening outdoors. Thus, An. farauti mosquitoes were able to avoid insecticide exposure and still maintain transmission. Thirty years on and the Solomon Islands are planning for intensified malaria control and localized elimination; but little is currently known about the behaviour of the vectors and how they will respond to intensified control. Methods In the elimination area, Temotu Province, standard entomological collection methods were conducted in typical coastal villages to determine the vector, its ecology, biting density, behaviour, longevity, and vector efficacy. These vector surveys were conducted pre-intervention and post-intervention following indoor residual spraying and distribution of long-lasting insecticidal nets. Results Anopheles farauti was the only anopheline in Temotu Province. In 2008 (pre-intervention, this species occurred in moderate to high densities (19.5-78.5 bites/person/night and expressed a tendency to bite outdoors, early in the night (peak biting time 6-8 pm. Surveys post intervention showed that there was little, if any, reduction in biting densities and no reduction in the longevity of the vector population. After adjusting for human behaviour, indoor biting was reduced from 57% pre-intervention to 40% post-intervention. Conclusion In an effort to learn from historical mistakes and develop successful elimination programmes, there is a need for implementing complimentary vector control tools that can target exophagic and early biting vectors. Intensified indoor residual spraying and long-lasting insecticide net use has further promoted the early, outdoor feeding behaviour of An. farauti in the Solomon Islands

  10. Insecticidal activity of the essential oil of Thymus transcaspicus against Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Leila Dargahi; Kamal Razavi-Azarkhiavi; Mohammad Ramezani; Mohammad Reza Abaee; Javad Behravan

    2014-01-01

    Objective:To investigate the insecticidal activity of the essential oil of Thymus transcaspicus (T. transcaspicus) against Anopheles stephensi (An. stephensi). Methods:An. stephensi were exposed to 31, 63, 125 and 250 µg/L of essential oil of T. transcaspicus for 24 h. Results:The most toxicity was observed at 250 µg/L of essential oil with the LC50 values of 134.1 µg/L after 24 h. Conclusions:The essential oil of T. transcaspicus exhibited strong insecticidal activity against An. stephensi which can be attributed to its constituent especially carvacrol and thymol phenols.

  11. Evaluation of a eucalyptus-based repellent against Anopheles spp. in Tanzania.

    Science.gov (United States)

    Trigg, J K

    1996-06-01

    A eucalyptus-based insect repellent (PMD) with the principal active ingredient p-menthane-3,8-diol was evaluated in the field in comparison with deet. In human landing catches in Tanzania, 3 formulations of PMD were tested against Anopheles gambiae and An. funestus. Repellents, applied to the legs and feet at doses chosen as used in practice, gave complete protection from biting for between 6 and 7.75 h, depending upon the formulation type, with no significant difference between PMD and deet in terms of efficacy and duration of protection. PMID:8827599

  12. A peroxidase/dual oxidase system modulates midgut epithelial immunity in Anopheles gambiae.

    Science.gov (United States)

    Kumar, Sanjeev; Molina-Cruz, Alvaro; Gupta, Lalita; Rodrigues, Janneth; Barillas-Mury, Carolina

    2010-03-26

    Extracellular matrices in diverse biological systems are cross-linked by dityrosine covalent bonds catalyzed by the peroxidase/oxidase system. We show that a peroxidase, secreted by the Anopheles gambiae midgut, and dual oxidase form a dityrosine network that decreases gut permeability to immune elicitors. This network protects the microbiota by preventing activation of epithelial immunity. It also provides a suitable environment for malaria parasites to develop within the midgut lumen without inducing nitric oxide synthase expression. Disruption of this barrier results in strong and effective pathogen-specific immune responses. PMID:20223948

  13. Immune factor Gambif1, a new rel family member from the human malaria vector, Anopheles gambiae.

    OpenAIRE

    Barillas-Mury, C; Charlesworth, A.; Gross, I; Richman, A; Hoffmann, J A; Kafatos, F C

    1996-01-01

    A novel rel family member, Gambif1 (gambiae immune factor 1), has been cloned from the human malaria vector, Anopheles gambiae, and shown to be most similar to Drosophila Dorsal and Dif. Gambif1 protein is translocated to the nucleus in fat body cells in response to bacterial challenge, although the mRNA is present at low levels at all developmental stages and is not induced by infection. DNA binding activity to the kappaB-like sites in the A.gambiae Defensin and the Drosophila Diptericin and...

  14. The JAK-STAT Pathway Controls Plasmodium vivax Load in Early Stages of Anopheles aquasalis Infection

    OpenAIRE

    Bahia, Ana C; Marina S Kubota; Antonio J Tempone; Helena R. C. Araújo; Bruno A M Guedes; Orfanó, Alessandra S.; Wanderli P Tadei; Ríos-Velásquez, Claudia M.; Han, Yeon S.; SECUNDINO Nágila F.C.; Barillas-Mury, Carolina; Pimenta, Paulo F. P.; Traub-Csekö, Yara M.

    2011-01-01

    Malaria affects 300 million people worldwide every year and 450,000 in Brazil. In coastal areas of Brazil, the main malaria vector is Anopheles aquasalis, and Plasmodium vivax is responsible for the majority of malaria cases in the Americas. Insects possess a powerful immune system to combat infections. Three pathways control the insect immune response: Toll, IMD, and JAK-STAT. Here we analyze the immune role of the A. aquasalis JAK-STAT pathway after P. vivax infection. Three genes, the tran...

  15. The JAK-STAT pathway controls Plasmodium vivax load in early stages of Anopheles aquasalis infection.

    OpenAIRE

    Bahia, Ana C; Marina S Kubota; Antonio J Tempone; Helena R. C. Araújo; Bruno A M Guedes; Orfanó, Alessandra S.; Wanderli P Tadei; Ríos-Velásquez, Claudia M.; Han, Yeon S.; SECUNDINO Nágila F.C.; Carolina Barillas-Mury; Pimenta, Paulo F. P.; Traub-Csekö, Yara M.

    2011-01-01

    Malaria affects 300 million people worldwide every year and 450,000 in Brazil. In coastal areas of Brazil, the main malaria vector is Anopheles aquasalis, and Plasmodium vivax is responsible for the majority of malaria cases in the Americas. Insects possess a powerful immune system to combat infections. Three pathways control the insect immune response: Toll, IMD, and JAK-STAT. Here we analyze the immune role of the A. aquasalis JAK-STAT pathway after P. vivax infection. Three genes, the tran...

  16. A Peroxidase/Dual Oxidase System Modulates Midgut Epithelial Immunity in Anopheles gambiae

    Science.gov (United States)

    Kumar, Sanjeev; Molina-Cruz, Alvaro; Gupta, Lalita; Rodrigues, Janneth; Barillas-Mury, Carolina

    2012-01-01

    Extracellular matrices in diverse biological systems are crosslinked by dityrosine covalent bonds catalyzed by the peroxidase/oxidase system. We show that the Immunomodulatory Peroxidase (IMPer), an enzyme secreted by the mosquito Anopheles gambiae midgut, and dual oxidase (Duox) form a dityrosine network that decreases gut permeability to immune elicitors and protects the microbiota by preventing activation of epithelial immunity. It also provides a suitable environment for malaria parasites to develop within the midgut lumen without inducing nitric oxide synthase expression. Disruption of this barrier results in strong and effective pathogen-specific immune responses. PMID:20223948

  17. Gene expression patterns associated with blood-feeding in the malaria mosquito Anopheles gambiae

    OpenAIRE

    Hogan James R; Lobo Neil F; Harker Brent W; Hillenmeyer Maureen E; Kern Marcia K; Hong Young S; Dana Ali N; Romans Patricia; Collins Frank H

    2005-01-01

    Abstract Background Blood feeding, or hematophagy, is a behavior exhibited by female mosquitoes required both for reproduction and for transmission of pathogens. We determined the expression patterns of 3,068 ESTs, representing ~2,000 unique gene transcripts using cDNA microarrays in adult female Anopheles gambiae at selected times during the first two days following blood ingestion, at 5 and 30 min during a 40 minute blood meal and at 0, 1, 3, 5, 12, 16, 24 and 48 hours after completion of t...

  18. Chemical composition and insecticidal activity of plant essential oils from Benin against Anopheles gambiae (Giles)

    Science.gov (United States)

    2013-01-01

    Background Insecticide resistance in sub-Saharan Africa and especially in Benin is a major public health issue hindering the control of the malaria vectors. Each Anopheles species has developed a resistance to one or several classes of the insecticides currently in use in the field. Therefore, it is urgent to find alternative compounds to conquer the vector. In this study, the efficacies of essential oils of nine plant species, which are traditionally used to avoid mosquito bites in Benin, were investigated. Methods Essential oils of nine plant species were extracted by hydrodistillation, and their chemical compositions were identified by GC-MS. These oils were tested on susceptible “kisumu” and resistant “ladji-Cotonou” strains of Anopheles gambiae, following WHO test procedures for insecticide resistance monitoring in malaria vector mosquitoes. Results Different chemical compositions were obtained from the essential oils of the plant species. The major constituents identified were as follows: neral and geranial for Cymbopogon citratus, Z-carveol, E-p-mentha-1(7),8-dien-2-ol and E-p-mentha-2,8-dienol for Cymbopogon giganteus, piperitone for Cymbopogon schoenanthus, citronellal and citronellol for Eucalyptus citriodora, p-cymene, caryophyllene oxide and spathulenol for Eucalyptus tereticornis, 3-tetradecanone for Cochlospermum tinctorium and Cochlospermum planchonii, methyl salicylate for Securidaca longepedunculata and ascaridole for Chenopodium ambrosioides. The diagnostic dose was 0.77% for C. citratus, 2.80% for E. tereticornis, 3.37% for E. citriodora, 4.26% for C. ambrosioides, 5.48% for C. schoenanthus and 7.36% for C. giganteus. The highest diagnostic doses were obtained with S. longepedunculata (9.84%), C. tinctorium (11.56%) and C. planchonii (15.22%), compared to permethrin 0.75%. A. gambiae cotonou, which is resistant to pyrethroids, showed significant tolerance to essential oils from C. tinctorium and S. longepedunculata as expected but was

  19. Species of Oukuriella Epler (Diptera, Chironomidae inside freshwater sponges in Brazil

    Directory of Open Access Journals (Sweden)

    Fabio de Oliveira Roque

    2004-06-01

    Full Text Available Larvae of Oukuriella Epler, 1986 (Diptera, Chironomidae inside freshwater sponges are reported for the first time in Brazil.Espécies de Oukuriella Epler (Diptera, Chironomidae no interior de esponjas de água doce no Brasil. Larvas de Oukuriella Epler, 1986 no interior de esponjas de água doce são registradas pela primeira vez no Brasil.

  20. Descriptions of syntypes of Brumptamyia brumpti (Lsrrousse, 1920 (Diptera: Psychodidae-Phlebotominae

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    Paul Williams

    1988-09-01

    Full Text Available The male and female of Brumptomyia brumpti (Larrousse, 1920, the type species of the genus Brumptomyia França & Parrot, 1921 (Diptera: Psychodidae - phlebotominae are redescribed from syntypes in the British Museum (Natural History.É apresentada a redescrição de sinotipos macho e fêmea de Brumptomya brumpti (Larrousse, 1920, a espécie típica do gênero Brumptomyia França e Parrot, 1921 (diptera: Psychodidae - Phlebotominae.

  1. Bromeliad-associated mosquitoes from Atlantic forest in Santa Catarina Island, southern Brazil (Diptera, Culicidae, with new records for the State of Santa Catarina Mosquitos associados a bromélias em Mata Atlântica na Ilha de Santa Catarina, sul do Brasil (Diptera, Culicidae, com novos registros para o Estado de Santa Catarina

    Directory of Open Access Journals (Sweden)

    Gerson Azulim Müller

    Full Text Available Bromeliad-associated mosquitoes (Diptera: Culicidae in Atlantic Forest in Florianópolis, Santa Catarina, southern Brazil, were studied, examining plants of Vriesea philippocoburgi Wawra and Aechmea lindenii (E. Morren Baker var. lindenii at secondary Atlantic rain forest, and A. lindenii and Vriesea friburgensis Mez var. paludosa (L. B. Smith at "restinga" per month, during 12 months. No immature forms of mosquitoes were collected from A. lindenii in the secondary forest. Collections obtained 368 immature mosquitoes, none of them from A. lindenii from rain forest. Culex (Microculex spp. constituted 79.8% of the total, Wyeomyia (Phoniomyia spp. 17.93%, and Anopheles (Kerteszia cruzii (Dyar & Knab, 1908 only 1.36%. The study shows the great predominance of species of medical importance not yet proved, and the small number of immature stages of anopheline mosquitoes. The rainfall, but not the mean temperatures, significantly influenced the quantity of mosquitoes from V. philippocoburgi. Significant differences between the quantities of immature forms of all the bromeliad species were found, and the shape of the plants could be important to the abundance of mosquitoes. All six species of Cx. (Microculex found are recorded for the first time in the State of Santa Catarina, and all six species of Wyeomyia (Phoniomyia are recorded for the first time in bromeliads in this state.Mosquitos (Diptera: Culicidae associados a bromélias em Mata Atlântica na Ilha de Santa Catarina, no Estado de Santa Catarina, foram estudados. Foram examinadas mensalmente plantas de Vriesea philippocoburgi Wawra e Aechmea lindenii (E. Morren Baker var. lindenii de floresta atlântica pluvial ombrófila e A. lindenii e Vriesea friburgensis Mez var. paludosa (L. B. Smith de restinga, durante 12 meses. As coletas resultaram em 368 formas imaturas de mosquitos, sendo que nenhuma foi coletada em A. lindenii de mata ombrófila. Culex (Microculex spp. constituíram 79,8% do total

  2. Systematics of mosquito disease vectors (Diptera, Culicidae): impact of molecular biology and cladistic analysis.

    Science.gov (United States)

    Munstermann, L E; Conn, J E

    1997-01-01

    The field of medical entomology, by nature of its association with problems of human health, has been conservative in its application of molecular and computer technologies to systematic research. Recently, however, these methods have opened new interpretations for systematics of disease vectors. Medically important insects, particularly mosquitoes, are among those more thoroughly described by conventional taxonomy, and thereby provide a secure framework for testing congruencies with molecular data. In turn, molecular investigations have provided a stimulus to vector systematics in the discovery and delineation of cryptic species complexes, as well as providing new perspectives on relationships at higher taxonomic divisions. In this review, examples involving cladistic analysis, cytogenetics--in situ hybridization, isoenzymes, DNA sequencing, and restriction fragment polymorphism are drawn from the following taxa: Aedes communis; Aedes (Ochlerotatus) group G; Aedes (Stegomyia) species including A. aegypti, A. albopictus, and A. scutellaris group; Anopheles albitarsis, Anopheles dirus, Anopheles gambiae, Anopheles nuneztovari, Anopheles pseudopunctipennis, and Anopheles punctulatus groups; Culex pipiens and the Culex subgenus Melanoconion; and the tribe Sabethini.

  3. Karakteristik Habitat Larva Anopheles spp. di Desa Sungai Nyamuk, Daerah Endemik Malaria di Kabupaten Nunukan, Kalimantan Utara

    Directory of Open Access Journals (Sweden)

    Sugiarto Sugiarto

    2016-07-01

    Full Text Available A research about Habitat Characteristics of Anopheles spp. larvae was done in Sungai Nyamuk Village, Nunukan District, North Kalimantan Province from August 2010 to January 2012. This research aims to analyse the characteristics of breeding places of Anopheles spp. The larvae taken from various types of habitat with detention and maintained until it was developed into mosquitoes, then later identified. The results showed that there are four types of potential breeding places of Anopheles spp. ie lagoon, ditches, fish ponds and marshes. Anopheles types that are found consist of five species, namely An. vagus, An. subpictus, An. sundaicus, An. indefinitus dan An. peditaeniatus. Types of potential breeding places are dominated by the unused fish pond, with the substrate in the form of mud and water is not flowing, located around settlements surrounded by grasses, shrubs and trees. Breeding places contains of aquatic plants such as grasses and moss. Predators are found in the form of a dragonfly nymph, crustaceans, tadpoles and small fish. Early malaria vector control at the level of the larvae is a critical point of the success of malaria elimination programs in endemic areas.

  4. Differential attractiveness of humans to the African malaria vector Anopheles gambiae Giles - Effects of host characteristics and parasite infection

    NARCIS (Netherlands)

    Mukabana, W.R.

    2002-01-01

    The results of a series of studies designed to understand the principal factors that determine the differential attractiveness of humans to the malaria vector Anopheles gambiae are described in this thesis. Specific

  5. Toxicity of six plant extracts and two pyridine alkaloids from Ricinus communis against the malaria vector Anopheles gambiae

    Science.gov (United States)

    The African malaria vector, Anopheles gambiae s.s., is known to feed selectively on certain plants for sugar sources. However, the adaptive significance of this behavior especially on how the extracts of such plants impact on the fitness of this vector has not been explored. This study determined th...

  6. Malaria in Suriname: a new era : impact of modified intervention strategies on Anopheles darlingi populations and malaria incidence

    NARCIS (Netherlands)

    Hiwat-van Laar, H.

    2011-01-01

    Malaria is an infectious disease caused by Plasmodiumblood parasites which live inside the human host and are spread by Anopheles mosquitoes.Every year an estimated 225 million new cases and near 800.000 malaria deaths are reported. Control of the disease is a formidable task involving all three liv

  7. Peculiar liquid-feeding and pathogen transmission behavior of Aedes togoi and comparison with Anopheles sinensis

    Science.gov (United States)

    Lee, Sang Joon; Kang, Dooho; Lee, Seung Chul; Ha, Young-Ran

    2016-02-01

    Female mosquitoes transmit various diseases as vectors during liquid-feeding. Identifying the determinants of vector efficiency is a major scientific challenge in establishing strategies against these diseases. Infection rate and transmission efficiency are interconnected with the mosquito-induced liquid-feeding flow as main indexes of vector efficiency. However, the relationship between liquid-feeding characteristics and pathogen remains poorly understood. The liquid-feeding behavior of Aedes togoi and Anopheles sinensis was comparatively investigated in conjunction with vector efficiency via micro-particle image velocimetry. The flow rates and ratio of the ejection volume of Aedes togoi were markedly higher than those of Anophels sinensis. These differences would influence pathogen re-ingestion. Wall shear stresses of these mosquito species were also clearly discriminatory affecting the infective rates of vector-borne diseases. The variations in volume of two pump chambers and diameter of proboscis of these mosquito species were compared to determine the differences in the liquid-feeding process. Liquid-feeding characteristics influence vector efficiency; hence, this study can elucidate the vector efficiency of mosquitoes and the vector-pathogen interactions and contribute to the development of strategies against vector-borne diseases.

  8. Indirect evidence that agricultural pesticides select for insecticide resistance in the malaria vector Anopheles gambiae.

    Science.gov (United States)

    Luc, Djogbénou S; Benoit, Assogba; Laurette, Djossou; Michel, Makoutode

    2016-06-01

    We investigated the possible relationship between the agricultural use of insecticides and the emergence of insecticide resistance. Bioassays were conducted using simulated mosquito larval habitats and well known Anopheles gambiae strains. Soil samples were collected from vegetable production areas in Benin, including one site with insecticide use, one site where insecticides had not been used for two months, and a third where insecticides had not been used. Pupation and emergence rates were very low in pyrethroid-susceptible strains when exposed to soil that had been recently exposed to insecticides. Pupation and emergence rates in strains with the kdr mutation alone or both the kdr and Ace-1 mutations were much higher. Overall, strains with the kdr mutation survived at higher rates compared to that without kdr mutation. Although this study is observational, we provide indirect evidence indicating that soils from agricultural areas contain insecticide residues that can play a role in the emergence of insecticide resistance in Anopheles. This aspect should be taken into account to better utilize the insecticide in the context of integrated pest management programs.

  9. Population genetics of Plasmodium resistance genes in Anopheles gambiae: no evidence for strong selection.

    Science.gov (United States)

    Obbard, D J; Linton, Y-M; Jiggins, F M; Yan, G; Little, T J

    2007-08-01

    Anopheles mosquitoes are the primary vectors for malaria in Africa, transmitting the disease to more than 100 million people annually. Recent functional studies have revealed mosquito genes that are crucial for Plasmodium development, but there is presently little understanding of which genes mediate vector competence in the wild, or evolve in response to parasite-mediated selection. Here, we use population genetic approaches to study the strength and mode of natural selection on a suite of mosquito immune system genes, CTL4, CTLMA2, LRIM1, and APL2 (LRRD7), which have been shown to affect Plasmodium development in functional studies. We sampled these genes from two African populations of An. gambiae s.s., along with several closely related species, and conclude that there is no evidence for either strong directional or balancing selection on these genes. We highlight a number of challenges that need to be met in order to apply population genetic tests for selection in Anopheles mosquitoes; in particular the dearth of suitable outgroup species and the potential difficulties that arise when working within a closely-related species complex. PMID:17688548

  10. Phytochemistry and larvicidal activity of Eucalyptus camaldulensisagainst malaria vector,Anopheles stephensi

    Institute of Scientific and Technical Information of China (English)

    Sedaghat Mohamad Medhi; SaneiAli Reza; Khnavi Mahnaz; Abai Mohammad Reza; Hadjiakhoondi Abbas; MohtaramiFatemeh; VatandoostHassan

    2010-01-01

    Objective:To determine phytochemistry and larvicidal activity ofEucalyptus camaldulensis againstAnopheles stephensi.Methods:The chemical compositions of the leaf essential oils were analyzed using gas chromatography/mass spectrometry (GC/MS). The larvicidal activity of essential oils and extract of leaf were tested against 4th instar larvae of laboratory-rearedAnopheles stephensi.Results:GC/MS analyses identified the presence of28 compounds corresponding to 99.60%of the total oil. The main constituents in the leaf essential oil were1,8-cineole(69.46%), γ-Terpinene(15.10%), α-Pinene(5.47%)and Globulol(2%). The leaf extract and volatile oil exerted significant larvicidal activity withLC50 values of89.85 and397.75ppm, respectively. Clear dose-response relationships were established with the highest dose of320 ppm essential oil extract resulted almost100% mortality in the population.Conclusions:The larvicidal properties suggest that the essential oil of plant is a potential source of valuable larvicidal compounds against malaria vector and can be used as an alternative to synthetic insecticides.

  11. Ecology of Anopheles dthali Patton in Bandar Abbas District, Hormozgan Province, Southern Iran

    Directory of Open Access Journals (Sweden)

    H Vatandoost

    2007-05-01

    Full Text Available Ecology of Anopheles dthali was studied in Bandar Abbas County, where there is indigenous malaria. Anopheles dthali plays as a secondary malaria vector in the region. It is active throughout the year in mountainous area with two peaks of activity, whereas in coastal area it has one peak. There is no report of hibernation or aestivation for this species in the re¬gion. Precipitin tests on specimens from different parts showed that 15.6-20.8% were positive for human blood. This species usually rests outdoors. It has different larval habitats. Insecticides susceptibility tests on adult females exhibited susceptibil¬ity to all insecticides recommended by WHO. LT50 for the currently used insecticide, lambda-cyhalothrin, is measured less than one minute. The irritability tests to pyrethroid insecticides, showed that permethrin and lambda-cyhalothrin had more irritancy compared to deltamethrin and cyfluthrin. Larval bioassay using malathion, chlorpyrifos, temephos and fenithrothion did not show any sing of resistance to these larvicides at the diagnostic dose. It is recommended that all the decision makers should consider the results of our study for any vector control measures in the region.

  12. Ecology of Anopheles dthali Patton in Bandar Abbas District, Hormozgan Province, Southern Iran

    Directory of Open Access Journals (Sweden)

    H Vatandoost

    2007-06-01

    Full Text Available Ecology of Anopheles dthali was studied in Bandar Abbas County, where there is indigenous malaria. Anopheles dthali plays as a secondary malaria vector in the region. It is active throughout the year in mountainous area with two peaks of activity, whereas in coastal area it has one peak. There is no report of hibernation or aestivation for this species in the re¬gion. Precipitin tests on specimens from different parts showed that 15.6-20.8% were positive for human blood. This species usually rests outdoors. It has different larval habitats. Insecticides susceptibility tests on adult females exhibited susceptibil¬ity to all insecticides recommended by WHO. LT50 for the currently used insecticide, lambda-cyhalothrin, is measured less than one minute. The irritability tests to pyrethroid insecticides, showed that permethrin and lambda-cyhalothrin had more irritancy compared to deltamethrin and cyfluthrin. Larval bioassay using malathion, chlorpyrifos, temephos and fenithrothion did not show any sing of resistance to these larvicides at the diagnostic dose. It is recommended that all the decision makers should consider the results of our study for any vector control measures in the region.

  13. Spermless males elicit large-scale female responses to mating in the malaria mosquito Anopheles gambiae

    Science.gov (United States)

    Thailayil, Janis; Magnusson, Kalle; Godfray, H. Charles J.; Crisanti, Andrea; Catteruccia, Flaminia

    2011-01-01

    Anopheles gambiae sensu stricto is the major vector of malaria, a disease with devastating consequences for human health. Given the constant spread of the disease, alternative approaches to the use of insecticides are urgently needed to control vector populations. Females of this species undergo large behavioral changes after mating, which include a life-long refractoriness to further insemination and the induction of egg laying in blood-fed individuals. Genetic control strategies aimed at impacting Anopheles fertility through the release of sterile males are being advocated to reduce the size of mosquito field populations. Such strategies depend on the ability of the released sterile males to mate successfully with wild females and to switch off the female receptivity to further copulation. Here we evaluate the role of sperm in regulating female behavioral responses after mating in An. gambiae. We developed spermless males by RNAi silencing of a germ cell differentiation gene. These males mated successfully and preserved standard accessory gland functions. Females mated to spermless males exhibited normal postcopulatory responses, which included laying large numbers of eggs upon blood feeding and becoming refractory to subsequent insemination. Moreover, spermless males induced transcriptional changes in female reproductive genes comparable to those elicited by fertile males. Our data demonstrate that, in contrast to Drosophila, targeting sperm in An. gambiae preserves normal male and female reproductive behavior for the traits and time frame analyzed and validate the use of approaches based on incapacitation or elimination of sperm for genetic control of vector populations to block malaria transmission. PMID:21825136

  14. "Comparison of Midgut Hemagglutination Activity in Three Different Geographical Populations of Anopheles stephensi"

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    HR Basseri

    2004-08-01

    Full Text Available Lectins that agglutinate red blood cells (RBCs were demonstrated in Anopheles stephensi mosquito midgut extracts using human (four groups: A, B, AB and O, RH+ rat, sheep and rabbit blood cells. Only rabbit RBCs showed agglutination reaction against the midgut extracts. Significant differences in hemagglutinin titers and carbohydrate specifity were detected between male and female mosquitoes as well as among three different geographical populations of Anopheles stephensi from south of Iran. Overall agglutinin levels were increased following a blood meal. The highest hemagglintination titers were due to Kazerun population. All hemagglutination assays were versus rabbit RBCS. A significant difference was detected among the number of egg-float ridges. Iranshahr population was different from Bandar-abbas and Kazerun population in egg-float ridges number. Bandr-abbas population was in the intermediate category. Iranshahr population fell between mysoransis and intermediate group and Kazerun population was between intermediate and type form. This study presents the first report on the occurrence of heterogeneous anti Rabbit RBC agglutinins in the midget extracts of the different geographical populations of An.stephensi with the sugar – binding specificities. The sugar- inhibition pattern was different between & within geographical population of An.stephensi.

  15. BEBERAPA ASPEK BIONOMIK ANOPHELES SP DI KABUPATEN SUMBA TENGAH, PROVINSI NUSA TENGGARA TIMUR

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    Ni Wayan Dewi Adyana

    2012-07-01

    Full Text Available Research Some Aspects of Anopheles sp Bionomik in Central Sumba Regency, Province of East Nusa Tenggara. Committed in the territory Maradesa Health Center. Data were collected by catching adult mosquitoes by using bait People inside and outside the home, a collection of breaks in the wall and at home, continued with larval surveys in all potential breeding places.  The results showed that the biting behavior tends eksofagik found on An. kochi, An. aconitus and An.barbirostris with bite density peaks in An. aconitus (0.6 persons/hour with a biting peak at 20:00 to 21:00. Behavior tends eksofilik break in An. kochi, An. aconitus, An. tesselatus, An. barbirostris, An. vagus, An.flavirostris, An. maculatus and An. indefinitus with the highest density in An.aconitus (0.9 persons/hour at 1:00 a.m. to 2:00 a.m. Anopheles larvae breeding places found in the small hole in the ground, creek, wetland, non-permanent irrigation, water reservoirs in the vegetable garden, ditches, puddles, swamps, springs, with species that are found as An.kochi, An.aconitus, An. tesselatus, An. barbirostris, An. vagus, An. flavirostris, An. maculatus, An. indefinitus and An. annullaris

  16. The effect of temperature on Anopheles mosquito population dynamics and the potential for malaria transmission.

    Directory of Open Access Journals (Sweden)

    Lindsay M Beck-Johnson

    Full Text Available The parasites that cause malaria depend on Anopheles mosquitoes for transmission; because of this, mosquito population dynamics are a key determinant of malaria risk. Development and survival rates of both the Anopheles mosquitoes and the Plasmodium parasites that cause malaria depend on temperature, making this a potential driver of mosquito population dynamics and malaria transmission. We developed a temperature-dependent, stage-structured delayed differential equation model to better understand how climate determines risk. Including the full mosquito life cycle in the model reveals that the mosquito population abundance is more sensitive to temperature than previously thought because it is strongly influenced by the dynamics of the juvenile mosquito stages whose vital rates are also temperature-dependent. Additionally, the model predicts a peak in abundance of mosquitoes old enough to vector malaria at more accurate temperatures than previous models. Our results point to the importance of incorporating detailed vector biology into models for predicting the risk for vector borne diseases.

  17. Identification of four evolutionarily related G protein-coupled receptors from the malaria mosquito Anopheles gambiae

    DEFF Research Database (Denmark)

    Belmont, Martin; Cazzamali, Giuseppe; Williamson, Michael;

    2006-01-01

    The mosquito Anopheles gambiae is an important vector for malaria, which is one of the most serious human parasitic diseases in the world, causing up to 2.7 million deaths yearly. To contribute to our understanding of A. gambiae and to the transmission of malaria, we have now cloned four evolutio......The mosquito Anopheles gambiae is an important vector for malaria, which is one of the most serious human parasitic diseases in the world, causing up to 2.7 million deaths yearly. To contribute to our understanding of A. gambiae and to the transmission of malaria, we have now cloned four...... evolutionarily related G protein-coupled receptors (GPCRs) from this mosquito and expressed them in Chinese hamster ovary cells. After screening of a library of thirty-three insect or other invertebrate neuropeptides and eight biogenic amines, we could identify (de-orphanize) three of these GPCRs as...... relationship to the A. gambiae and other insect AKH receptors suggested that it is a receptor for an AKH-like peptide. This is the first published report on evolutionarily related AKH, corazonin, and CCAP receptors in mosquitoes....

  18. FAUNA ANOPHELES DI DAERAH PANTAI BEKAS HUTAN MANGROVE KECAMATAN PADANG CERMIN KABUPATEN LAMPUNG SELATAN

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    N. Sushanti Idris-Idram

    2012-09-01

    Full Text Available Intensive mosquito collections were carried out in two villages in subdistrict of Padangcermin during 1992-1993. The method of mosquito collections consisted of night landing on man indoor and outdoor, night resting indoor and outdoor around cattle shelters, light trap in cattle shelters, daytime resting indoor and outdoor, as well as larvae collections to identify anophelines breeding sites. Sixteen anophelines i.e. Anopheles sundaicus, An. subpictus, An. vagus, An. indefinitus, An. nigerrimus, An. peditaeniatus, An. kochi, An. barbirostris, An. bambumbrosus, An. annularis, An. separatus, An. tesselatus, An. aconitus, An. umbrosus, An. leucosphyrus and An. letifer were collected. Among these mosquitos, An. sundaicus was found predominant, followed by An. vagus and An. subpictus. Other species were collected in small numbers. The behavior of Anopheles sundaicus, An. subpictus and An. vagus were exophagic and endophilic. The larvae of An. sundaicus was found only in brackish standing water such as abandoned shrimp ponds, An. subpictus in brackish standing water as well as fresh standing water, while An. vagus was found only in fresh standing water. Breeding sites of An. sundaicus was characterized by pond with floating algae while An. subpictus and An. vagus were not depending on vegetation.

  19. A natural Anopheles-associated Penicillium chrysogenum enhances mosquito susceptibility to Plasmodium infection

    Science.gov (United States)

    Angleró-Rodríguez, Yesseinia I.; Blumberg, Benjamin J.; Dong, Yuemei; Sandiford, Simone L.; Pike, Andrew; Clayton, April M.; Dimopoulos, George

    2016-01-01

    Whereas studies have extensively examined the ability of bacteria to influence Plasmodium infection in the mosquito, the tripartite interactions between non-entomopathogenic fungi, mosquitoes, and Plasmodium parasites remain largely uncharacterized. Here we report the isolation of a common mosquito-associated ascomycete fungus, Penicillium chrysogenum, from the midgut of field-caught Anopheles mosquitoes. Although the presence of Pe. chrysogenum in the Anopheles gambiae midgut does not affect mosquito survival, it renders the mosquito significantly more susceptible to Plasmodium infection through a secreted heat-stable factor. We further provide evidence that the mechanism of the fungus-mediated modulation of mosquito susceptibility to Plasmodium involves an upregulation of the insect’s ornithine decarboxylase gene, which sequesters arginine for polyamine biosynthesis. Arginine plays an important role in the mosquito’s anti-Plasmodium defense as a substrate of nitric oxide production, and its availability therefore has a direct impact on the mosquito’s susceptibility to the parasite. While this type of immunomodulatory mechanism has already been demonstrated in other host-pathogen interaction systems, this is the first report of a mosquito-associated fungus that can suppress the mosquito’s innate immune system in a way that would favor Plasmodium infection and possibly malaria transmission. PMID:27678168

  20. Genetic and phenotypic variation of the malaria vector Anopheles atroparvus in southern Europe

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    Romi Roberto

    2011-01-01

    Full Text Available Abstract Background There is a growing concern that global climate change will affect the potential for pathogen transmission by insect species that are vectors of human diseases. One of these species is the former European malaria vector, Anopheles atroparvus. Levels of population differentiation of An. atroparvus from southern Europe were characterized as a first attempt to elucidate patterns of population structure of this former malaria vector. Results are discussed in light of a hypothetical situation of re-establishment of malaria transmission. Methods Genetic and phenotypic variation was analysed in nine mosquito samples collected from five European countries, using eight microsatellite loci and geometric morphometrics on 21 wing landmarks. Results Levels of genetic diversity were comparable to those reported for tropical malaria vectors. Low levels of genetic (0.004 FST An. atroparvus populations spanning over 3,000 km distance. Genetic differentiation (0.202 FST An. atroparvus and Anopheles maculipennis s.s. Differentiation between sibling species was not so evident at the phenotype level. Conclusions Levels of population differentiation within An. atroparvus were low and not correlated with geographic distance or with putative physical barriers to gene flow (Alps and Pyrenées. While these results may suggest considerable levels of gene flow, other explanations such as the effect of historical population perturbations can also be hypothesized.

  1. Recent reduction in the water level of Lake Victoria has created more habitats for Anopheles funestus

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    Futami Kyoko

    2008-07-01

    Full Text Available Abstract Background The water level of Lake Victoria has fallen more than 1.5 m since 1998, revealing a narrow strip of land along the shore. This study determined whether the recent drop in the water level has created additional breeding grounds for malaria vectors. Methods The recent and past shorelines were estimated using landmarks and a satellite image. The locations of breeding habitats were recorded using a GPS unit during the high and low lake water periods. GIS was used to determine whether the breeding habitats were located on newly emerged land between the new and old shorelines. Results Over half of the breeding habitats existed on newly emerged land. Fewer habitats for the Anopheles gambiae complex were found during the low water level period compared to the high water period. However, more habitats for Anopheles funestus were found during the high water level period, and they were all located on the newly emerged land. Conclusion The recent reduction in water level of Lake Victoria has increased the amount of available habitat for A. funestus. The results suggest that the water drop has substantially affected the population of this malaria vector in the Lake Victoria basin, particularly because the lake has a long shoreline that may harbour many new breeding habitats.

  2. Comparative evaluation of systemic drugs for their effects against Anopheles gambiae.

    Science.gov (United States)

    Butters, Matthew P; Kobylinski, Kevin C; Deus, Kelsey M; da Silva, Ines Marques; Gray, Meg; Sylla, Massamba; Foy, Brian D

    2012-01-01

    Laboratory and field studies have shown that ivermectin, a drug that targets invertebrate ligand-gated ion channels (LGICs), is potently active against Anopheles spp. mosquitoes at concentrations present in human blood after standard drug administrations; thus ivermectin holds promise as a mass human-administered endectocide that could help suppress malaria parasite transmission. We evaluated other systemic LGIC-targeting drugs for their activities against the African malaria vector Anopheles gambiae using in vitro blood feeding assays. Eprinomectin, selamectin, moxidectin, and N-tert-butyl nodulisporamide were evaluated as potentially systemic drugs having similar modes of action to ivermectin; all primarily are agonists of invertebrate glutamate-gated chloride ion channels. Additionally, nitenpyram and spinosad were evaluated as systemic drugs that primarily work as agonists of nicotinic acetylcholine receptor channels. Only eprinomectin killed An. gambiae at concentrations that were comparable to ivermectin. At sub-lethal doses, nitenpyram and moxidectin marginally affected mosquito re-blood feeding ability. The macrocyclic lactones, particularly eprinomectin, caused significantly increased knockdown and significantly inhibited recovery in blood fed females. These data are a first step in evaluating drugs that might be eventually combined with, or substituted for ivermectin for future malaria parasite transmission control. PMID:22019935

  3. Études biologiques et comportementales de deux espèces de moustiques (Aedes albopictus et Anopheles arabiensis) vectrices de maladies en vue du développement de la Technique de l'Insecte Stérile (TIS) contre ces vecteurs à l'île de la Réunion

    OpenAIRE

    Oliva, Clélia

    2012-01-01

    Les femelles moustiques peuvent être vectrices de nombreux agents infectieux (virus, protozoaires, helminthes) pour l'Homme, qui peuvent être la cause de maladies graves comme le paludisme et la dengue. Ces maladies menacent respectivement 50 et 40% de la population mondiale ; le paludisme étant responsable de près d'un million de décès par an. Les méthodes de lutte anti-vectorielle destinées à limiter les populations vectrices et stopper la transmission de maladies, se heurtent au développem...

  4. Updated checklist of the mosquitoes (Diptera: Culicidae) of Belgium.

    Science.gov (United States)

    Boukraa, Slimane; Dekoninck, Wouter; Versteirt, Veerle; Schaffner, Francis; Coosemans, Marc; Haubruge, Eric; Francis, Frederic

    2015-12-01

    Most information about the systematics and bioecology of Belgian mosquitoes dates back from before 1950, and only scattered information was produced during the last decades. In this paper we review and update the list of mosquito species recorded in Belgium, from first report (1908) to 2015. Six genera and 31 species were recorded so far, including 28 autochthonous species and three invasive alien species recently recorded in Belgium: Aedes albopictus (Skuse 1894), Ae. japonicus japonicus (Theobald 1901), and Ae. koreicus (Edwards 1917). The six genera are Anopheles (five species), Aedes (sixteen species), Coquillettidia (one species), Culex (four species), Culiseta (four species), and Orthopodomyia (one species).

  5. Phylogenetic inference of calyptrates, with the first mitogenomes for Gasterophilinae (Diptera: Oestridae) and Paramacronychiinae (Diptera: Sarcophagidae)

    Science.gov (United States)

    Zhang, Dong; Yan, Liping; Zhang, Ming; Chu, Hongjun; Cao, Jie; Li, Kai; Hu, Defu; Pape, Thomas

    2016-01-01

    The complete mitogenome of the horse stomach bot fly Gasterophilus pecorum (Fabricius) and a near-complete mitogenome of Wohlfahrt's wound myiasis fly Wohlfahrtia magnifica (Schiner) were sequenced. The mitogenomes contain the typical 37 mitogenes found in metazoans, organized in the same order and orientation as in other cyclorrhaphan Diptera. Phylogenetic analyses of mitogenomes from 38 calyptrate taxa with and without two non-calyptrate outgroups were performed using Bayesian Inference and Maximum Likelihood. Three sub-analyses were performed on the concatenated data: (1) not partitioned; (2) partitioned by gene; (3) 3rd codon positions of protein-coding genes omitted. We estimated the contribution of each of the mitochondrial genes for phylogenetic analysis, as well as the effect of some popular methodologies on calyptrate phylogeny reconstruction. In the favoured trees, the Oestroidea are nested within the muscoid grade. Relationships at the family level within Oestroidea are (remaining Calliphoridae (Sarcophagidae (Oestridae, Pollenia + Tachinidae))). Our mito-phylogenetic reconstruction of the Calyptratae presents the most extensive taxon coverage so far, and the risk of long-branch attraction is reduced by an appropriate selection of outgroups. We find that in the Calyptratae the ND2, ND5, ND1, COIII, and COI genes are more phylogenetically informative compared with other mitochondrial protein-coding genes. Our study provides evidence that data partitioning and the inclusion of conserved tRNA genes have little influence on calyptrate phylogeny reconstruction, and that the 3rd codon positions of protein-coding genes are not saturated and therefore should be included. PMID:27019632

  6. Ammonium carbonate loss rates from lures differentially affect trap captures of Rhagoletis indifferens (Diptera: Tephritidae) and non-target flies

    Science.gov (United States)

    Western cherry fruit fly, Rhagoletis indifferens Curran (Diptera: Tephritidae), is a pest of cherry (Prunus spp.) in western North America that can be monitored using traps baited with ammonia. However, ammonia-based attractants also attract non-target Diptera that clutter traps. Here, the hypothe...

  7. A Study of the Essential Oils of Four Sudanese Accessions of Basil (Ocimum basilicum L. Against Anopheles Mosquito Larvae

    Directory of Open Access Journals (Sweden)

    Azhari H. Nour

    2009-01-01

    Full Text Available Problem statement: Certain basil essential oils were claimed to have a larvicidal activity towards mosquito's larvae. To test this claim the essential oils of four accessions of basil grown in Sudan were selected and tested for Anopheles larvae. Malaria is the major health problem in the Sudan and the whole country is now considered endemic, with varying degrees, about 35,000 deaths every year due to malaria. Anopheles mosquito is the major vector of malaria disease in Sudan. Search for larvicidal active compound(s is one of several attempts to fine effective and affordable ways to control this mosquito. To determine the toxic effects of basil essential oils extracted by steam distillation against Anopheles larvae. Approach: For the larvicidal bioassay, three concentrations (100, 300, 500 ppm of essential oil solutions of four basil accessions were prepared; 1 mL of ethanol was used to solubilize the oil in water (999 mL. In each concentration of oil solution were inserted 20 larvae (third instars. A set of controls using 0.1% ethanol and untreated sets of larvae in (tap water, were also run for comparison. Data were evaluated through regression analysis, from the regression line; the LC50 values were read. The active ingredients were separated and/ or identified by TLC, IR and GC-MS. Results: Larvicidal activity of the essential oils is varied, lasted for about 9 h and thereafter decreased, LC50 values ranging from 190-300 ppm. Linalool, geraniol and eugenol are active components of basil essential oil against Anopheles larvae. Two accessions were caused 100% mortality at a concentration range 300-500 ppm for 3 h. Conclusion: These results indicated that basil essential oils have larvicidal activity towards Anopheles larvae. Therefore, could be affordable way to control this mosquito.

  8. Necrophagous diptera associated with wild animal carcasses in southern Brazil

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    Ândrio Z. da Silva

    2014-12-01

    Full Text Available Necrophagous Diptera associated with wild animal carcasses in southern Brazil. The aim of this study was to acquire a better knowledge concerning the diversity of necrophagous Diptera that develop on wild animal carcasses. For this purpose, the decomposition of six wild animal carcasses was observed in order to collect and identify the main species of necrophagous flies associated with the decomposition process. The carcasses were found on highways near the cities of Pelotas and Capão do Leão in the initial stage of decomposition, with no significant injuries or prior larval activity. Four wild animal models were represented in this study: two specimens of Didelphis albiventris Lund, 1840; two Tupinambis merianae Linnaeus, 1758; one Nothura maculosa Temminck, 1815; and one Cerdocyon thous Linnaeus, 1766. A total of 16,242 flies from 14 species were reared in the laboratory, where Muscidae presented the greatest diversity of necrophagous species. Overall, (i carcasses with larger biomass developed a higher abundance of flies and (ii the necrophagous community was dominated by Calliphoridae, two patterns that were predicted from published literature; and (iii the highest diversity was observed on the smaller carcasses exposed to the lowest temperatures, a pattern that may have been caused by the absence of the generalist predator Chrysomya albiceps (Wiedemann, 1819. (iv An UPGMA analysis revealed a similar pattern of clusters of fly communities, where the same species were structuring the groupings.

  9. Diversity and transmission competence in lymphatic filariasis vectors in West Africa, and the implications for accelerated elimination of Anopheles-transmitted filariasis

    OpenAIRE

    de Souza Dziedzom K; Koudou Benjamin; Kelly-Hope Louise A; Wilson Michael D; Bockarie Moses J; Boakye Daniel A

    2012-01-01

    Abstract Lymphatic Filariasis (LF) is targeted for elimination by the Global Programme for the Elimination of Lymphatic Filariasis (GPELF). The strategy adopted is based on the density dependent phenomenon of Facilitation, which hypothesizes that in an area where the vector species transmitting Wuchereria bancrofti are Anopheles mosquitoes, it is feasible to eliminate LF using Mass Drug Administration (MDA) because of the inability of Anopheles species to transmit low-density microfilaraemia....

  10. The relationship between wing length, blood meal volume, and fecundity for seven colonies of Anopheles species housed at the Armed Forces Research Institute of Medical Sciences, Bangkok, Thailand.

    Science.gov (United States)

    Phasomkusolsil, Siriporn; Pantuwattana, Kanchana; Tawong, Jaruwan; Khongtak, Weeraphan; Kertmanee, Yossasin; Monkanna, Nantaporn; Klein, Terry A; Kim, Heung-Chul; McCardle, Patrick W

    2015-12-01

    Established colonies of Anopheles campestris, Anopheles cracens, Anopheles dirus, Anopheles kleini, Anopheles minimus, Anopheles sawadwongporni, and Anopheles sinensis are maintained at the Armed Forces Research Institute of Medical Sciences (AFRIMS). Females were provided blood meals on human blood containing citrate as an anticoagulant using an artificial membrane feeder. The mean wing length, used as an estimate of body size, for each species was compared to blood-feeding duration (time), blood meal volume, and numbers of eggs oviposited. Except for An. campestris and An. cracens, there were significant interspecies differences in wing length. The mean blood meal volumes (mm(3)) of An. kleini and An. sinensis were significantly higher than the other 5 species. For all species, the ratios of unfed females weights/blood meal volumes were similar (range: 0.76-0.88), except for An. kleini (1.08) and An. cracens (0.52), that were significantly higher and lower, respectively. Adult females were allowed to feed undisturbed for 1, 3, and 5min intervals before blood feeding was interrupted. Except for An. campestris and An. sawadwongporni, the number of eggs oviposited were significantly higher for females that fed for 3min when compared to those that only fed for 1min. This information is critical to better understand the biology of colonized Anopheles spp. and their role in the transmission of malaria parasites as they relate to the relative size of adult females, mean volumes of blood of engorged females for each of the anopheline species, and the effect of blood feeding duration on specific blood meal volumes and fecundity.

  11. Development of a Gravid Trap for Collecting Live Malaria Vectors Anopheles gambiae s.l.

    Science.gov (United States)

    Dugassa, Sisay; Lindh, Jenny M.; Oyieke, Florence; Mukabana, Wolfgang R.; Lindsay, Steven W.; Fillinger, Ulrike

    2013-01-01

    Background Effective malaria vector control targeting indoor host-seeking mosquitoes has resulted in fewer vectors entering houses in many areas of sub-Saharan Africa, with the proportion of vectors outdoors becoming more important in the transmission of this disease. This study aimed to develop a gravid trap for the outdoor collection of the malaria vector Anopheles gambiae s.l. based on evaluation and modification of commercially available gravid traps. Methods Experiments were implemented in an 80 m2 semi-field system where 200 gravid Anopheles gambiae s.s. were released nightly. The efficacy of the Box, CDC and Frommer updraft gravid traps was compared. The Box gravid trap was tested to determine if the presence of the trap over water and the trap’s sound affected catch size. Mosquitoes approaching the treatment were evaluated using electrocuting nets or detergents added to the water in the trap. Based on the results, a new gravid trap (OviART trap) that provided an open, unobstructed oviposition site was developed and evaluated. Results Box and CDC gravid traps collected similar numbers (relative rate (RR) 0.8, 95% confidence interval (CI) 0.6–1.2; p = 0.284), whereas the Frommer trap caught 70% fewer mosquitoes (RR 0.3, 95% CI 0.2–0.5; p < 0.001). The number of mosquitoes approaching the Box trap was significantly reduced when the trap was positioned over a water-filled basin compared to an open pond (RR 0.7 95% CI 0.6–0.7; p < 0.001). This effect was not due to the sound of the trap. Catch size increased by 60% (RR 1.6, 1.2–2.2; p = 0.001) with the new OviART trap. Conclusion Gravid An. Gambiae s.s. females were visually deterred by the presence of the trapping device directly over the oviposition medium. Based on these investigations, an effective gravid trap was developed that provides open landing space for egg-laying Anopheles. PMID:23861952

  12. Development of a gravid trap for collecting live malaria vectors Anopheles gambiae s.l.

    Directory of Open Access Journals (Sweden)

    Sisay Dugassa

    Full Text Available BACKGROUND: Effective malaria vector control targeting indoor host-seeking mosquitoes has resulted in fewer vectors entering houses in many areas of sub-Saharan Africa, with the proportion of vectors outdoors becoming more important in the transmission of this disease. This study aimed to develop a gravid trap for the outdoor collection of the malaria vector Anopheles gambiae s.l. based on evaluation and modification of commercially available gravid traps. METHODS: Experiments were implemented in an 80 m(2 semi-field system where 200 gravid Anopheles gambiae s.s. were released nightly. The efficacy of the Box, CDC and Frommer updraft gravid traps was compared. The Box gravid trap was tested to determine if the presence of the trap over water and the trap's sound affected catch size. Mosquitoes approaching the treatment were evaluated using electrocuting nets or detergents added to the water in the trap. Based on the results, a new gravid trap (OviART trap that provided an open, unobstructed oviposition site was developed and evaluated. RESULTS: Box and CDC gravid traps collected similar numbers (relative rate (RR 0.8, 95% confidence interval (CI 0.6-1.2; p = 0.284, whereas the Frommer trap caught 70% fewer mosquitoes (RR 0.3, 95% CI 0.2-0.5; p < 0.001. The number of mosquitoes approaching the Box trap was significantly reduced when the trap was positioned over a water-filled basin compared to an open pond (RR 0.7 95% CI 0.6-0.7; p < 0.001. This effect was not due to the sound of the trap. Catch size increased by 60% (RR 1.6, 1.2-2.2; p = 0.001 with the new OviART trap. CONCLUSION: Gravid An. Gambiae s.s. females were visually deterred by the presence of the trapping device directly over the oviposition medium. Based on these investigations, an effective gravid trap was developed that provides open landing space for egg-laying Anopheles.

  13. Fumigant Toxicity of Phenylpropanoids Identified in Asarum sieboldii Aerial Parts to Lycoriella ingenua (Diptera: Sciaridae) and Coboldia fuscipes (Diptera: Scatopsidae).

    Science.gov (United States)

    Yi, Jee Hwan; Perumalsamy, Haribalan; Sankarapandian, Karuppasamy; Choi, Byeoung-Ryeol; Ahn, Young-Joon

    2015-06-01

    Lycoriella ingenua (Dufour) (Diptera: Sciaridae) and Coboldia fuscipes (Meigen) (Diptera: Scatopsidae) are two of the most economically important insect pests of cultivated mushrooms. The toxicities to the fly larvae of the three phenylpropanoids (methyleugenol, myristicin, and safrole) from aerial parts of Asarum sieboldii Miquel (Aristolochiaceae) were compared with those of the currently available carbamate insecticide benfuracarb. In a contact+fumigant mortality bioassay with L. ingenua and C. fuscipes larvae, methyleugenol (1.46 and 2.33 µg/cm2) was the most toxic compound, followed by safrole (2.03 and 2.59 µg/cm2) and myristicin (3.59 and 4.96 µg/cm2), based on 24-h LC50 values. The phenylpropanoids were less toxic than benfuracarb (LC50, 0.75 and 0.55 µg/cm2). In vapor-phase mortality tests with the larvae, the phenylpropanoids were consistently more toxic in closed versus open containers, indicating that the effect of the compounds was largely a result of vapor action. Global efforts to reduce the level of highly toxic synthetic insecticides in the agricultural environment justify further studies on A. sieboldii plant-derived products as potential fumigants for the control of mushroom fly populations in mushroom houses and mushroom compost.

  14. Anopheles culicifacies breeding in Sri Lanka and options for control through water management

    DEFF Research Database (Denmark)

    Konradsen, F; Matsuno, Y; Amerasinghe, F P;

    1998-01-01

    This paper assesses the options for control of malaria vectors through different water management practices in a natural stream in Sri Lanka. The association between water level in the stream and breeding of the immature stages of the primary vector Anopheles culicifacies was investigated and the...... a high degree of support from the local community is essential and consultation between government departments needed....... that by regulating the water level above 20 cm in the stream throughout the dry season the breeding of A. culicifacies could be significantly reduced. The intervention would have only limited impact on the water lost for agriculture and the management input would be minimal. However, for the intervention to work...

  15. Larvicidal activity of extracts from three Plumbago spp against Anopheles gambiae

    Directory of Open Access Journals (Sweden)

    Barasa M Maniafu

    2009-09-01

    Full Text Available Three Plumbago spp have been tested for mosquito larvicidal activity. The crude extracts exhibiting the highest larvicidal activity against Anopheles gambiae were hexane (LC50 = 6.4 μg/mL and chloroform (LC50 = 6.7 μg/mL extracts from Plumbago zeylanica Linn, chloroform (LC50 = 6.7 ug/mL extract from Plumbago stenophylla Bull and ethyl acetate (LC50 = 4.1 μg/mL extract from Plumbago dawei Rolfe. These LC50 values were within 95% confidence limits. 5-hydroxy-2-methyl-1,4-naphthoquinone (plumbagin 1 (LC50 = 1.9 μg/mL and β-sitosterol 2 were characterised from ethyl acetate extract of root bark of P. dawei, a native medicinal plant growing in Kenya, based on spectral analysis and comparisons with data in literature.

  16. Anopheles barbirostris Confirmation as Malaria Vector in Waikabubak through the Detection of Circumsporozoit Protein

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    Yuneu Yuliasih

    2012-06-01

    Full Text Available Anopheline species confirmed as malaria vector if the salivary gland contained sporozoites. One of the method to confirmed it was through an Enzyme-Linked Immunosorbent Assay (ELISA. The aim of this study was to investigate the presence of circum sporozoite protein (CSP in the mosquito of Anopheles barbirostris with ELISA method. The study was conducted in malaria endemic area named Modu Waimaringu Village, Waikabubak District, Sumba Barat Regency in March 2011. The study design was cross-sectional study, mosquito for the ELISA test were collected only from animal bait. ELISA method examination used on An. barbirostris body parts (i.e. the head-thorax where sporozoites of P. falciparum or P. Vivax possibly be found. The results showed that 40 samples of An. barbirostris mosquitoes which acquired from the mosquite bait in Modu Waimaringu Village was negative (100%. It means that there was no CSP found and An. barbirostris was not a malaria vector in the area

  17. Avoidance Behavior to Essential Oils by Anopheles minimus, a Malaria Vector in Thailand.

    Science.gov (United States)

    Nararak, Jirod; Sathantriphop, Sunaiyana; Chauhan, Kamal; Tantakom, Siripun; Eiden, Amanda L; Chareonviriyaphap, Theeraphap

    2016-03-01

    Essential oils extracted from 4 different plant species--citronella (Cymbopogon nardus), hairy basil (Ocimum americanum), sweet basil (Ocimum basilicum), and vetiver (Vetiveria zizanioides)-were investigated for their irritant and repellent activities against Anopheles minimus, using an excito-repellency test system. Pure essential oils were used in absolute ethanol at the concentrations of 0.5%, 1%, 2.5%, and 5% (v/v) compared with deet. At the lowest concentration of 0.5%, hairy basil displayed the best irritant and repellent effects against An. minimus. Citronella and vetiver at 1-5% showed strong irritant effects with>80% escape, while repellent effects of both oils were observed at 1% and 2.5% citronella (73-89% escape) and at 5% vetiver (83.9% escape). Sweet basil had only moderate irritant action at 5% concentration (69.6% escape) and slightly repellent on test mosquitoes (mosquito repellent products for protection against An. minimus. PMID:27105214

  18. [The mosquitocidal efficacy of microcapsules of alpha-cypermethrin against Anopheles sinensis].

    Science.gov (United States)

    Pan, K Y; Ye, B H; Zhi, C L

    1994-01-01

    The efficacy of spraying of alpha-cypermethrin microcapsule for the control of Anopheles sinensis was investigated when alpha-cypermethrin microcapsule was sprayed at 0.5 g/m2, the KT50 was 7.9 min and a 100% of 24 hours' mortality of An. sinensis, the efficacy being similar to that of the emulsion. 180 days after spray, the KT50 was 28.2 min, the 24 hours' mortality was 85.7%, the residual efficacy was 3 times over that of the emulsion. In the mimic field experiment, similar results were obtained. In the field trial, the residual efficacy of the alpha-cypermethrin microcapsule was 5.9 times that of the emulsion. Alpha-cypermethrin microcapsules is recommended as a good formulation of mosquitocide for mosquito control, considering its mosquitocidal efficacy and residual efficacy.

  19. Larvicidal activity of oak Quercus infectoria Oliv. (Fagaceae) gall extracts against Anopheles stephensi Liston.

    Science.gov (United States)

    Aivazi, Ali-Ashraf; Vijayan, V A

    2009-06-01

    There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five extracts tested for larvicidal activity against the fourth instar larvae, with LC(50) of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC(50) values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant promising for the development of new botanical larvicide. PMID:19148681

  20. Larvicidal activity of oak Quercus infectoria Oliv. (Fagaceae) gall extracts against Anopheles stephensi Liston.

    Science.gov (United States)

    Aivazi, Ali-Ashraf; Vijayan, V A

    2009-06-01

    There is a growing interest in the use of botanical insecticides to reduce the use of synthetic pesticides in order to avoid environmental side effects. Anopheles stephensi is the primary vector of urban malaria, an endemic disease in India. So, an effort to assay An. stephensi larvae with gall extracts of Quercus infectoria was made under laboratory conditions at Mysore. Ethyl-acetate extract was found to be the most effective of all the five extracts tested for larvicidal activity against the fourth instar larvae, with LC(50) of 116.92 ppm followed by gallotannin, n-butanol, acetone, and methanol with LC(50) values of 124.62, 174.76, 299.26, and 364.61 ppm, respectively. The efficacy in killing mosquito larvae may make this plant promising for the development of new botanical larvicide.

  1. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes

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    Martha L. Salas

    1994-01-01

    Full Text Available The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per trial, however the Tecojate strain developed higher sporozoite loads. Intravenous inoculation of Aotus monkeys with sporozoites obtained from both anopheline strains resulted in successful blood infections. Animals infected with sporozoites from the Tecojate strain presented a patent period of 21-32 days whereas parasitemia appeared between days 19-53 in monkeys infected with sporozites from Cartagena strain.

  2. Development of sporogonic cycle of Plasmodium vivax in experimentally infected Anopheles albimanus mosquitoes.

    Science.gov (United States)

    Salas, M L; Romero, J F; Solarte, Y; Olano, V; Herrera, M A; Herrera, S

    1994-01-01

    The sporogonic cycle of Plasmodium vivax was established and maintained under laboratory conditions in two different strains of Anopheles albimanus mosquitoes using as a parasite source blood from human patients or from Aotus monkeys infected with the VCC-2 P.vivax colombian isolate. Both the Tecojate strain isolate from Guatemala and the Cartagena strain from the colombian Pacific coast were susceptible to infections with P.vivax. A higher percentage of Cartagena mosquitoes was infected per trial, however the Tecojate strain developed higher sporozoite loads. Intravenous inoculation of Aotus monkeys with sporozoites obtained from both anopheline strains resulted in successful blood infections. Animals infected with sporozoites from the Tecojate strain presented a patent period of 21-32 days whereas parasitemia appeared between days 19-53 in monkeys infected with sporozites from Cartagena strain. PMID:7565121

  3. Anopheles gambiae eicosanoids modulate Plasmodium berghei survival from oocyst to salivary gland invasion

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    Susana Ramos

    2014-08-01

    Full Text Available Eicosanoids affect the immunity of several pathogen/insect models, but their role on the Anopheles gambiae response to Plasmodium is still unknown. Plasmodium berghei-infected mosquitoes were injected with an eicosanoid biosynthesis inhibitor, indomethacin (IN, or a substrate, arachidonic acid (AA, at day 7 or day 12 post-infection (p.i.. Salivary gland invasion was evaluated by sporozoite counts at day 21 p.i. IN promoted infection upon sporozoite release from oocysts, but inhibited infection when sporozoites were still maturing within the oocysts, as observed by a reduction in the number of sporozoites reaching the salivary glands. AA treatment had the opposite effect. We show for the first time that An. gambiae can modulate parasite survival through eicosanoids by exerting an antagonistic or agonistic effect on the parasite, depending on its stage of development.

  4. “Highly evolvable malaria vectors: the genomes of 16 Anopheles mosquitoes”

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    Neafsey, Daniel E.; Waterhouse, Robert M.; Abai, Mohammad R.; Aganezov, Sergey S.; Alekseyev, Max A.; Allen, James E.; Amon, James; Arcà, Bruno; Arensburger, Peter; Artemov, Gleb; Assour, Lauren A.; Basseri, Hamidreza; Berlin, Aaron; Birren, Bruce W.; Blandin, Stephanie A.; Brockman, Andrew I.; Burkot, Thomas R.; Burt, Austin; Chan, Clara S.; Chauve, Cedric; Chiu, Joanna C.; Christensen, Mikkel; Costantini, Carlo; Davidson, Victoria L.M.; Deligianni, Elena; Dottorini, Tania; Dritsou, Vicky; Gabriel, Stacey B.; Guelbeogo, Wamdaogo M.; Hall, Andrew B.; Han, Mira V.; Hlaing, Thaung; Hughes, Daniel S.T.; Jenkins, Adam M.; Jiang, Xiaofang; Jungreis, Irwin; Kakani, Evdoxia G.; Kamali, Maryam; Kemppainen, Petri; Kennedy, Ryan C.; Kirmitzoglou, Ioannis K.; Koekemoer, Lizette L.; Laban, Njoroge; Langridge, Nicholas; Lawniczak, Mara K.N.; Lirakis, Manolis; Lobo, Neil F.; Lowy, Ernesto; MacCallum, Robert M.; Mao, Chunhong; Maslen, Gareth; Mbogo, Charles; McCarthy, Jenny; Michel, Kristin; Mitchell, Sara N.; Moore, Wendy; Murphy, Katherine A.; Naumenko, Anastasia N.; Nolan, Tony; Novoa, Eva M.; O'Loughlin, Samantha; Oringanje, Chioma; Oshaghi, Mohammad A.; Pakpour, Nazzy; Papathanos, Philippos A.; Peery, Ashley N.; Povelones, Michael; Prakash, Anil; Price, David P.; Rajaraman, Ashok; Reimer, Lisa J.; Rinker, David C.; Rokas, Antonis; Russell, Tanya L.; Sagnon, N'Fale; Sharakhova, Maria V.; Shea, Terrance; Simão, Felipe A.; Simard, Frederic; Slotman, Michel A.; Somboon, Pradya; Stegniy, Vladimir; Struchiner, Claudio J.; Thomas, Gregg W.C.; Tojo, Marta; Topalis, Pantelis; Tubio, José M.C.; Unger, Maria F.; Vontas, John; Walton, Catherine; Wilding, Craig S.; Willis, Judith H.; Wu, Yi-Chieh; Yan, Guiyun; Zdobnov, Evgeny M.; Zhou, Xiaofan; Catteruccia, Flaminia; Christophides, George K.; Collins, Frank H.; Cornman, Robert S.; Crisanti, Andrea; Donnelly, Martin J.; Emrich, Scott J.; Fontaine, Michael C.; Gelbart, William; Hahn, Matthew W.; Hansen, Immo A.; Howell, Paul I.; Kafatos, Fotis C.; Kellis, Manolis; Lawson, Daniel; Louis, Christos; Luckhart, Shirley; Muskavitch, Marc A.T.; Ribeiro, José M.; Riehle, Michael A.; Sharakhov, Igor V.; Tu, Zhijian; Zwiebel, Laurence J.; Besansky, Nora J.

    2015-01-01

    Variation in vectorial capacity for human malaria among Anopheles mosquito species is determined by many factors, including behavior, immunity, and life history. To investigate the genomic basis of vectorial capacity and explore new avenues for vector control, we sequenced the genomes of 16 anopheline mosquito species from diverse locations spanning ~100 million years of evolution. Comparative analyses show faster rates of gene gain and loss, elevated gene shuffling on the X chromosome, and more intron losses, relative to Drosophila. Some determinants of vectorial capacity, such as chemosensory genes, do not show elevated turnover, but instead diversify through protein-sequence changes. This dynamism of anopheline genes and genomes may contribute to their flexible capacity to take advantage of new ecological niches, including adapting to humans as primary hosts. PMID:25554792

  5. Wolbachia infections in natural Anopheles populations affect egg laying and negatively correlate with Plasmodium development

    Science.gov (United States)

    Shaw, W. Robert; Marcenac, Perrine; Childs, Lauren M.; Buckee, Caroline O.; Baldini, Francesco; Sawadogo, Simon P.; Dabiré, Roch K.; Diabaté, Abdoulaye; Catteruccia, Flaminia

    2016-01-01

    The maternally inherited alpha-proteobacterium Wolbachia has been proposed as a tool to block transmission of devastating mosquito-borne infectious diseases like dengue and malaria. Here we study the reproductive manipulations induced by a recently identified Wolbachia strain that stably infects natural mosquito populations of a major malaria vector, Anopheles coluzzii, in Burkina Faso. We determine that these infections significantly accelerate egg laying but do not induce cytoplasmic incompatibility or sex-ratio distortion, two parasitic reproductive phenotypes that facilitate the spread of other Wolbachia strains within insect hosts. Analysis of 221 blood-fed A. coluzzii females collected from houses shows a negative correlation between the presence of Plasmodium parasites and Wolbachia infection. A mathematical model incorporating these results predicts that infection with these endosymbionts may reduce malaria prevalence in human populations. These data suggest that Wolbachia may be an important player in malaria transmission dynamics in Sub-Saharan Africa. PMID:27243367

  6. PRELIMINARY NOTES ON THE DEVELOPMENT OF DDT RESISTANCE IN ANOPHELES CULICIFACIES

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    A.Zaini

    1973-09-01

    Full Text Available Anopheles culicifacies is the vector of malaria in southeastern part of Iran, India, West Pakistan and Ceylon. In 1959 the LC50 % DDT in the Panchmahal district of Gujarat state (India had increased. DDT resistant population of A. culicifacies has been reported from West Pakistan, Burma and Iran. After application of DDT in 1959, the density of A. culicifacies decreased sharply. The susceptibility test carried out in 1963 showed that the LC50 was 0.5%.After DDT spraying, followed by Dieldrin, for about 10 years the density of A. culicifacies was so negligible that it was not possible to perform susceptibility tests. By April and May of 1973 the density of A.culicifacies in Saidabad, Khairabad and Hit in Baluchesten province, Southeast of Iran, increased to about 500 per shelter. The susceptibility tests carried out showed that A. culicfacies is resistant to DDT and susceptible to Dieldrin and Malathion.

  7. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae.

    Science.gov (United States)

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A; Serhan, Charles N; Ribeiro, Jose M; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to 'remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A4. Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. PMID:26100162

  8. Genome expression analysis of Anopheles gambiae: responses to injury, bacterial challenge, and malaria infection.

    Science.gov (United States)

    Dimopoulos, George; Christophides, George K; Meister, Stephan; Schultz, Jörg; White, Kevin P; Barillas-Mury, Carolina; Kafatos, Fotis C

    2002-06-25

    The complex gene expression responses of Anopheles gambiae to microbial and malaria challenges, injury, and oxidative stress (in the mosquito and/or a cultured cell line) were surveyed by using cDNA microarrays constructed from an EST-clone collection. The expression profiles were broadly subdivided into induced and down-regulated gene clusters. Gram+ and Gram- bacteria and microbial elicitors up-regulated a diverse set of genes, many belonging to the immunity class, and the response to malaria partially overlapped with this response. Oxidative stress activated a distinctive set of genes, mainly implicated in oxidoreductive processes. Injury up- and down-regulated gene clusters also were distinctive, prominently implicating glycolysis-related genes and citric acid cycle/oxidative phosphorylation/redox-mitochondrial functions, respectively. Cross-comparison of in vivo and in vitro responses indicated the existence of tightly coregulated gene groups that may correspond to gene pathways. PMID:12077297

  9. Energy metabolism affects susceptibility of Anopheles gambiae mosquitoes to Plasmodium infection.

    Science.gov (United States)

    Oliveira, Jose Henrique M; Gonçalves, Renata L S; Oliveira, Giselle A; Oliveira, Pedro L; Oliveira, Marcus F; Barillas-Mury, Carolina

    2011-06-01

    Previous studies showed that Anopheles gambiae L3-5 females, which are refractory (R) to Plasmodium infection, express higher levels of genes involved in redox-metabolism and mitochondrial respiration than susceptible (S) G3 females. Our studies revealed that R females have reduced longevity, faster utilization of lipid reserves, impaired mitochondrial state-3 respiration, increased rate of mitochondrial electron leak and higher expression levels of several glycolytic enzyme genes. Furthermore, when state-3 respiration was reduced in S females by silencing expression of the adenine nucleotide translocator (ANT), hydrogen peroxide generation was higher and the mRNA levels of lactate dehydrogenase increased in the midgut, while the prevalence and intensity of Plasmodium berghei infection were significantly reduced. We conclude that there are broad metabolic differences between R and S An. gambiae mosquitoes that influence their susceptibility to Plasmodium infection. PMID:21320598

  10. A mosquito lipoxin/lipocalin complex mediates innate immune priming in Anopheles gambiae

    Science.gov (United States)

    Ramirez, Jose Luis; de Almeida Oliveira, Giselle; Calvo, Eric; Dalli, Jesmond; Colas, Romain A.; Serhan, Charles N.; Ribeiro, Jose M.; Barillas-Mury, Carolina

    2015-01-01

    Exposure of Anopheles gambiae mosquitoes to Plasmodium infection enhances the ability of their immune system to respond to subsequent infections. However, the molecular mechanism that allows the insect innate immune system to ‘remember' a previous encounter with a pathogen has not been established. Challenged mosquitoes constitutively release a soluble haemocyte differentiation factor into their haemolymph that, when transferred into Naive mosquitoes, also induces priming. Here we show that this factor consists of a Lipoxin/Lipocalin complex. We demonstrate that innate immune priming in mosquitoes involves a persistent increase in expression of Evokin (a lipid carrier of the lipocalin family), and in their ability to convert arachidonic acid to lipoxins, predominantly Lipoxin A4. Plasmodium ookinete midgut invasion triggers immune priming by inducing the release of a mosquito lipoxin/lipocalin complex. PMID:26100162

  11. Susceptibility of Anopheles maculipennis to different classes of insecticides in West Azarbaijan Province, Northwestern Iran

    Institute of Scientific and Technical Information of China (English)

    Ali; Reza; Chavshin; Farrokh; Dabiri; Hassan; Vatandoost; Mulood; Mohammadi; Bavani

    2015-01-01

    Objective: To determine the susceptibility status of Anopheles maculipennis(An. maculipennis) against the major insecticides used in the health sectors in West Azarbaijan Province, Northwestern Iran.Methods: Unfed 3-5 days old adult females of An. maculipennis were collected across the West Azarbaijan Province and were subjected to evaluation of their susceptibility following World Health Organization recommended protocol against six insecticides(permethrin, deltamethrin, propoxur, bendiocarb, malathion and dieldrin) belonging to four different classes. Results: In this study, 916 specimens of An. maculipennis were examined against the insecticides which indicated that An. maculipennis was tolerant to permethrin, deltamethrin and dielderin, but displayed resistance against propoxur, bendiocarb and malathion. Conclusions: The pattern of resistance in An. maculipennis could be attributed to the agricultural landscapes, agricultural pesticides used and the exposure of the mosquitoes to insecticides. Logical cooperation is needed between the agriculture and health sectors to ensure the judicious use of pesticides in each sector and the management of probable resistance.

  12. RESISTANCE OF ANOPHELES STEPHENSI LISTON TO MALATHION IN THE PROVICE OF FARS, SOUTHERN IRAN

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    N.Eshghy

    1985-08-01

    Full Text Available Anopheles Stephensi is an important malaria vector in southern Iran. This species developed resistance to DDT in 1975 and subsequently to dieldrin in 1960. Since 1968 this species has been under pressure of malathin house sprayin. 50% w.d.p. , 2g/m2, 1-2 rounds per year. Susceptibility tests carried out with malathion impregnated papers during 1979 showed that An.stephensi has acquired resistant to malathion too. With regard to the 0.1% propoxur, a study was carried out to obtain base-line data in the localities under routine observations and also the discriminating dosage that could kill 100% of An.stephensi. The objective of the present paper is to summarize and discuss briefly the field investigations concerning insecticide resistance in An.stephensi.

  13. PROPOXUR SELECTION OF THE ADULTS OF ANOPHELES STEPHENSI FROM MINAB, SOUTH OF IRAN

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    H. Edalat

    1997-10-01

    Full Text Available Anopheles stephensi is the main malaria vector in south of Iran. It has been known to be resistant to DDT, malathion and dieldrin. After appearance of resistance the area was treated with propoxur, at the rate of 2 g/m2 twice a year for 14 successive years. This species is still susceptible to propoxur. In order to forecast the possibility of development of propoxur resistance in An.stephensi, the females of this species were put under the pressure of propoxur for 14 generations in 1988. Fourteen generations of propoxur selection on the adult females of An.stephensi resulted in an increase in LT60 from 8.5 min to 24.30 minutes, i.e. 2.86 fold increase in tolerance.

  14. COMPARATIVE TOXICITIES OF FOUR WHO-RECOMMENDED LARVICIDES AGAINST LAB STRAIN OF ANOPHELES STEPHENSI IN IRAN

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    H. Vatandoost

    1999-08-01

    Full Text Available Investigation on the current response of An.stephensi larvae to four WHO recommended larvicides, i.e. Malathion, temephos, chlorpyrifos and fenitrothion, were carried out in the laboratory in 1999. Diagnostic concentrations of pesticides only yielded 100% mortality with malathion. In contrast, levels of susceptibility to temphos, chlorpyrifos (0.025 mg/l and temephos (0.625 mg/l killed 72%, 90% and 87% of the population of An. Stephensi, respectively. At the LC50 level the efficacies of chlorpyrifos and fenitrothion was higher than malathion and temephos. Relative toxicity of chlorpyrifos and fenitrothion was 6 and 24 times more than temephos and Malathion. The findings of this study suggest that the diagnostic dose of organophosphate larvicides depends on time, location, strain and genetically background of resistance to insecticides; hence they can be attributed to all species of anopheles.

  15. The impact of insecticides management linked with resistance expression in Anopheles spp. populations.

    Science.gov (United States)

    Silva, Guilherme Liberato da; Pereira, Thiago Nunes; Ferla, Noeli Juarez; Silva, Onilda Santos da

    2016-06-01

    The resistance of some species of Anopheles to chemical insecticides is spreading quickly throughout the world and has hindered the actions of prevention and control of malaria. The main mechanism responsible for resistance in these insects appears to be the target site known as knock-down resistance (kdr), which causes mutations in the sodium channel. Even so, many countries have made significant progress in the prevention of malaria, focusing largely on vector control through long-lasting insecticide nets (LLINs), indoor residual spraying and (IRS) of insecticides. The objective of this review is to contribute with information on the more applied insecticides for the control of the main vectors of malaria, its effects, and the different mechanisms of resistance. Currently it is necessary to look for others alternatives, e.g. biological control and products derived from plants and fungi, by using other organisms as a possible regulator of the populations of malaria vectors in critical outbreaks. PMID:27383351

  16. Molecular taxonomy provides new insights into anopheles species of the neotropical arribalzagia series.

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    Giovan F Gómez

    Full Text Available Phylogenetic analysis of partial mitochondrial cytochrome oxidase c subunit I (COI and nuclear internal transcribed spacer 2 (ITS2 sequences were used to evaluate initial identification and to investigate phylogenetic relationships of seven Anopheles morphospecies of the Arribalzagia Series from Colombia. Phylogenetic trees recovered highly supported clades for An. punctimaculas.s., An. calderoni, An. malefactor s.l., An. neomaculipalpus, An. apicimacula s.l., An. mattogrossensis and An. peryassui. This study provides the first molecular confirmation of An. malefactorfrom Colombia and discovered conflicting patterns of divergence for the molecular markers among specimens from northeast and northern Colombia suggesting the presence of two previously unrecognized Molecular Operational Taxonomic Units (MOTUs. Furthermore, two highly differentiated An. apicimacula MOTUs previously found in Panama were detected. Overall, the combined molecular dataset facilitated the detection of known and new Colombian evolutionary lineages, and constitutes the baseline for future research on their bionomics, ecology and potential role as malaria vectors.

  17. Checklist of the Diptera (Insecta of Finland: an introduction and a summary of results

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    Jere Kahanpää

    2014-09-01

    Full Text Available Nearly thirty-five years have passed since Hackman published his “Check list of the Finnish Diptera” (1980. The number of true flies (Diptera known from Finland has increased by more than two thousand species since then. At the same time, hundreds of erroneous records have been recognized and purged from the checklist. ZooKeys issue 441 provides a new checklist of the Diptera species of the Republic of Finland. This introductory paper presents the rationale behind the project, provides technical documentation on the checklist format and sources used, and summarizes the results. The remaining papers in this issue cover one or more Diptera families in detail. Two electronic appendices are provided: supporting data (additional references to first published records and the previous checklist and a complete list of Finnish Diptera taxa in Darwin Core compliant format for easy computer access and processing. The new checklist records 6920 fly species from Finland, 2932 belonging to the nematoceran or lower flies and 3989 to the suborder Brachycera. The changes since 1980 are most prominent in the Lower Diptera. For example, more than 400 non-biting midges (Chironomidae have been added since 1980, and the number of moth flies (Psychodidae known from Finland has more than tripled. Among the larger families, large increases in known Finnish species are also seen in Cecidomyiidae (161% increase, Pipunculidae (98%, and Chironomidae (90%.

  18. Spatial and sex-specific dissection of the Anopheles gambiae midgut transcriptome

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    Mahairaki Vassiliki

    2007-01-01

    Full Text Available Abstract Background The midgut of hematophagous insects, such as disease transmitting mosquitoes, carries out a variety of essential functions that mostly relate to blood feeding. The midgut of the female malaria vector mosquito Anopheles gambiae is a major site of interactions between the parasite and the vector. Distinct compartments and cell types of the midgut tissue carry out specific functions and vector borne pathogens interact and infect different parts of the midgut. Results A microarray based global gene expression approach was used to compare transcript abundance in the four major female midgut compartments (cardia, anterior, anterior part of posterior and posterior part of posterior midgut and between the male and female Anopheles gambiae midgut. Major differences between the female and male midgut gene expression relate to digestive processes and immunity. Each compartment has a distinct gene function profile with the posterior midgut expressing digestive enzyme genes and the cardia and anterior midgut expressing high levels of antimicrobial peptide and other immune gene transcripts. Interestingly, the cardia expressed several known anti-Plasmodium factors. A parallel peptidomic analysis of the cardia identified known mosquito antimicrobial peptides as well as several putative short secreted peptides that are likely to represent novel antimicrobial factors. Conclusion The A. gambiae sex specific midgut and female midgut compartment specific transcriptomes correlates with their known functions. The significantly greater functional diversity of the female midgut relate to hematophagy that is associated with digestion and nutrition uptake as well as exposes it to a variety of pathogens, and promotes growth of its endogenous microbial flora. The strikingly high proportion of immunity related factors in the cardia tissue most likely serves the function to increase sterility of ingested sugar and blood. A detailed characterization of the

  19. Observations on the swarming and mating behaviour of Anopheles funestus from southern Mozambique

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    Thompson R

    2003-02-01

    Full Text Available Abstract Background Control of malaria by the release of genetically modified mosquitoes refractory to transmission is now becoming a possibility. In many areas of Africa, Anopheles gambiae is found together with an equally important vector, An. funestus. Given their sympatry and the likelihood of a similar mating period some aspects of the mating behaviour of An. gambiae s.l. and An. funestus are likely to differ. We therefore attempted to characterise the swarming behaviour of An. funestus and to determine if any aspects of the observed behaviour differed from that recorded for the M form of An. gambiae from São Tomé. Methods In March – May 2002 the swarming, mating, house exiting and resting behaviour of Anopheles funestus was studied by direct observation in Mozambique. Swarming males and insects in copula were collected by sweep net. Wing lengths of males collected resting, exiting houses, swarming and mating were measured and the wingbeat frequency distribution of individual insects, in free flight confined inside netting covered paper cups, was also determined. Results Mono-specific swarms occurred at sunset in relatively open areas close to houses used for resting. Mating pairs were seen 11 ± 3.7 min after the start of swarming. The number of total pairs observed being inversely proportional to the time difference between the start of swarming and the first pairing. The great majority of females mated before feeding. Male or female size did not appear to affect mating success or other behaviours. During the study, ambient temperatures decreased and female, but not male, wing size increased. At 516 Hz, the flight tone of female An. funestus was similar to the 497 Hz of the local An. gambiae. Males dispersed if light or dark artificial horizontal markers were placed underneath naturally occurring swarms. Conclusion Differential response to markers would be sufficient for swarming in An. funestus and An. gambiae s.l. to occur in

  20. Bendiocarb, a potential alternative against pyrethroid resistant Anopheles gambiae in Benin, West Africa

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    Irish Seth

    2010-07-01

    Full Text Available Abstract Background Anopheles gambiae, the main malaria vector in Benin has developed high level of resistance to pyrethroid insecticides, which is a serious concern to the future use of long-lasting insecticidal nets (LLIN and indoor residual spraying (IRS. In this context, one of the pathways available for malaria vector control would be to investigate alternative classes of insecticides with different mode of action than that of pyrethroids. The goal of this study was to evaluate under field conditions the efficacy of a carbamate (bendiocarb and an organophosphate (fenitrothion against pyrethroid-resistant An. gambiae s.s. Methods Wild populations and females from laboratory colonies of five days old An. gambiae were bio-assayed during this study. Two pyrethroids (deltamethrin and alphacypermethrin, an organophosphate (fenitrothion, a carbamate (bendiocarb and a mixture of an organophosphate (chlorpyriphos + a pyrethroid deltamethrin were compared in experimental huts as IRS treatments. Insecticides were applied in the huts using a hand-operated compression sprayer. The deterrency, exophily, blood feeding rate and mortality induced by these insecticides against An. gambiae were compared to the untreated control huts. Results Deltamethrin, alphacypermethrin and bendiocarb treatment significantly reduced mosquito entry into the huts (p An. gambiae (in the first month and 77.8% (in the fourth month. Bendiocarb and the mixture chlorpyriphos/deltamethrin mortality rates ranged from 97.9 to 100% the first month and 77.7-88% the third month respectively. Conclusion After four months, fenitrothion, bendiocarb and the mixture chlorpyriphos/deltamethrin performed effectively against pyrethroid-resistant Anopheles. These results showed that bendiocarb could be recommended as an effective insecticide for use in IRS operations in Benin, particularly as the mixture chlorpyriphos/deltamethrin does not have WHOPES authorization and complaints were mentioned