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Sample records for anopheline mosquito recta

  1. Why are anopheline mosquitoes not present in the Seychelles?

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    Goodman Steven M

    2011-02-01

    Full Text Available Abstract Background Species of anopheline mosquitoes are largely distributed over emerged lands around the world and, within the tropics, few areas are without these insects, which are vectors of malaria parasites. Among the exceptions is the Seychelles archipelago in the western Indian Ocean. However, in the Aldabra island group, located in the extreme western portion of the archipelago, Anopheles gambiae s.l. was introduced, leading to massive proliferation and then elimination, with the most recent autochthonous malaria cases recorded in 1931. Methods In order to re-examine the absence of anopheline mosquitoes in the Seychelles, an entomological field survey was conducted in December 2008 at 17 sites on four granitic islands, including Mahé and Praslin, and ten sites on coralline atolls in the extreme west, including Aldabra. Results No evidence of larval or adult anophelines was found at the surveyed sites, which supports their absence in the Seychelles. Conclusions In the granitic islands of the Seychelles, the climate is favourable for anophelines. However, these islands are protected by their remoteness and prevailing seasonal winds. In addition, stagnant freshwater, required in anopheline larval development, is relatively uncommon on the granitic islands because of the steep slopes. In the southwestern atolls (Aldabra and Providence-Farquhar groups, the presence of a long dry season of up to nine months and the total absence of permanent natural freshwater prevents the breeding of anophelines and their successful colonization. The Seychelles does not have any native land mammals and like in other parts of the world (Antarctica, Iceland, New Caledonia, Central Pacific islands their absence is associated with the lack of anophelines. This suggests an obligatory relationship for anophelines to feed on terrestrial mammals, without alternative for blood-feeding sources, such as bats, birds and reptiles.

  2. The remarkable journey of adaptation of the Plasmodium falciparum malaria parasite to New World anopheline mosquitoes.

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    Molina-Cruz, Alvaro; Barillas-Mury, Carolina

    2014-08-01

    Plasmodium falciparum originated in Africa, dispersed around the world as a result of human migration and had to adapt to several different indigenous anopheline mosquitoes. Anophelines from the New World are evolutionary distant form African ones and this probably resulted in a more stringent selection of Plasmodium as it adapted to these vectors. It is thought that Plasmodium has been genetically selected by some anopheline species through unknown mechanisms. The mosquito immune system can greatly limit infection and P. falciparum evolved a strategy to evade these responses, at least in part mediated by Pfs47, a highly polymorphic gene. We propose that adaptation of P. falciparum to new vectors may require evasion of their immune system. Parasites with a Pfs47 haplotype compatible with the indigenous mosquito vector would be able to survive and be transmitted. The mosquito antiplasmodial response could be an important determinant of P. falciparum population structure and could affect malaria transmission in the Americas.

  3. The remarkable journey of adaptation of the Plasmodium falciparum malaria parasite to New World anopheline mosquitoes

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    Alvaro Molina-Cruz

    2014-08-01

    Full Text Available Plasmodium falciparum originated in Africa, dispersed around the world as a result of human migration and had to adapt to several different indigenous anopheline mosquitoes. Anophelines from the New World are evolutionary distant form African ones and this probably resulted in a more stringent selection of Plasmodium as it adapted to these vectors. It is thought that Plasmodium has been genetically selected by some anopheline species through unknown mechanisms. The mosquito immune system can greatly limit infection and P. falciparum evolved a strategy to evade these responses, at least in part mediated by Pfs47, a highly polymorphic gene. We propose that adaptation of P. falciparum to new vectors may require evasion of their immune system. Parasites with a Pfs47 haplotype compatible with the indigenous mosquito vector would be able to survive and be transmitted. The mosquito antiplasmodial response could be an important determinant of P. falciparum population structure and could affect malaria transmission in the Americas.

  4. Malaria Situation and Anopheline Mosquitoes in Qom Province, Central Iran

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    MR Abai

    2010-12-01

    Full Text Available "nAbstract "nBackground: The aims of this study was to analysis the current situation of malaria and to find the distribution of anopheline mosquitoes, as probable vectors of the disease, in Qom Province, central Iran. "nMethods: This study was carried out in two parts. First stage was data collection about malaria cases using recorded documents of patients in the Province health center, during 2001–2008. The second stage was entomological survey conducted by mosquito larval collection method in 4 villages with different geographical positions in 2008. Data were analyzed using Excel software. "nResults: Of 4456 blood slides, 10.9% out were positive. Most of cases were imported from other countries (90.4%, mainly from Afghanistan (56.5% and Pakistan (16.3%. Slide positive rate showed a maximum of 16.9% and a minimum of 2.9% in 2008 and 2007, respectively. Plasmodium vivax was causative agent of 93.75% of cases, fol­lowed by P. falciparum (6.25%. More than 15 years old age group contained the most malaria reported cases (66.7%. Two Anopheles species, An. superpictus and An. claviger were collected and identified. This is the first report of Anopheles claviger in Qom Province. "nConclusion: Malaria is in the control stage in Qom Province. The rate of local transmission is very low (only 1 case, shows Anopheles superpictus, as the main malaria vector of central part of Iran, can play its role in malaria transmission in the area. "n  "nKeywords: Malaria, Iran, Epidemiology

  5. Inhibition of Malaria Infection in Transgenic Anopheline Mosquitoes Lacking Salivary Gland Cells.

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    Yamamoto, Daisuke S; Sumitani, Megumi; Kasashima, Katsumi; Sezutsu, Hideki; Matsuoka, Hiroyuki

    2016-09-01

    Malaria is an important global public health challenge, and is transmitted by anopheline mosquitoes during blood feeding. Mosquito vector control is one of the most effective methods to control malaria, and population replacement with genetically engineered mosquitoes to block its transmission is expected to become a new vector control strategy. The salivary glands are an effective target tissue for the expression of molecules that kill or inactivate malaria parasites. Moreover, salivary gland cells express a large number of molecules that facilitate blood feeding and parasite transmission to hosts. In the present study, we adapted a functional deficiency system in specific tissues by inducing cell death using the mouse Bcl-2-associated X protein (Bax) to the Asian malaria vector mosquito, Anopheles stephensi. We applied this technique to salivary gland cells, and produced a transgenic strain containing extremely low amounts of saliva. Although probing times for feeding on mice were longer in transgenic mosquitoes than in wild-type mosquitoes, transgenic mosquitoes still successfully ingested blood. Transgenic mosquitoes also exhibited a significant reduction in oocyst formation in the midgut in a rodent malaria model. These results indicate that mosquito saliva plays an important role in malaria infection in the midgut of anopheline mosquitoes. The dysfunction in the salivary glands enabled the inhibition of malaria transmission from hosts to mosquito midguts. Therefore, salivary components have potential in the development of new drugs or genetically engineered mosquitoes for malaria control.

  6. Evolution of sexual traits influencing vectorial capacity in anopheline mosquitoes

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    Mitchell, Sara N.; Kakani, Evdoxia G.; South, Adam; Howell, Paul I.; Waterhouse, Robert M.; Catteruccia, Flaminia

    2015-01-01

    The availability of genome sequences from 16 anopheline species provides unprecedented opportunities to study the evolution of reproductive traits relevant for malaria transmission. In Anopheles gambiae, a likely candidate for sexual selection is male 20-hydroxyecdysone (20E). Sexual transfer of this steroid hormone as part of a mating plug dramatically changes female physiological processes intimately tied to vectorial capacity. By combining phenotypic studies with ancestral state reconstructions and phylogenetic analyses, we show that mating plug transfer and male 20E synthesis are both derived characters that have coevolved in anophelines, driving the adaptation of a female 20E-interacting protein that promotes oogenesis via mechanisms also favoring Plasmodium survival. Our data reveal coevolutionary dynamics of reproductive traits between the sexes likely to have shaped the ability of anophelines to transmit malaria. PMID:25722409

  7. Interrupting malaria transmission by genetic manipulation of anopheline mosquitoes

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    Marcelo Jacobs-Lorena

    2003-09-01

    Full Text Available Malaria ranks among the deadliest infectious diseases that kills more than one million persons everyyear. The mosquito is an obligatory vector for malaria transmission. In the mosquito, Plasmodiumundergoes a complex series of developmental events that includes transformation into severaldistinct morphological forms and the crossing of two different epithelia—midgut and salivarygland. Circumstantial evidence suggests that crossing of the epithelia requires specific interactionsbetween Plasmodium and epithelial surface molecules. By use of a phage display library we haveidentified a small peptide-SM1—that binds to the surfaces of the mosquito midgut and salivaryglands. Transgenic Anopheles stephensi mosquitoes expressing a SM1 tetramer from a bloodinducibleand gut-specific promoter are substantially impaired in their ability to sustain parasitedevelopment and transmission. A second effector gene, phospholipase A2, also impairs parasitetransmission in transgenic mosquitoes. These findings have important implications for the developmentof new strategies for malaria control.

  8. Landscape determinants and remote sensing of anopheline mosquito larval habitats in the western Kenya highlands

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    Beck Louisa

    2006-02-01

    Full Text Available Abstract Background In the past two decades the east African highlands have experienced several major malaria epidemics. Currently there is a renewed interest in exploring the possibility of anopheline larval control through environmental management or larvicide as an additional means of reducing malaria transmission in Africa. This study examined the landscape determinants of anopheline mosquito larval habitats and usefulness of remote sensing in identifying these habitats in western Kenya highlands. Methods Panchromatic aerial photos, Ikonos and Landsat Thematic Mapper 7 satellite images were acquired for a study area in Kakamega, western Kenya. Supervised classification of land-use and land-cover and visual identification of aquatic habitats were conducted. Ground survey of all aquatic habitats was conducted in the dry and rainy seasons in 2003. All habitats positive for anopheline larvae were identified. The retrieved data from the remote sensors were compared to the ground results on aquatic habitats and land-use. The probability of finding aquatic habitats and habitats with Anopheles larvae were modelled based on the digital elevation model and land-use types. Results The misclassification rate of land-cover types was 10.8% based on Ikonos imagery, 22.6% for panchromatic aerial photos and 39.2% for Landsat TM 7 imagery. The Ikonos image identified 40.6% of aquatic habitats, aerial photos identified 10.6%, and Landsate TM 7 image identified 0%. Computer models based on topographic features and land-cover information obtained from the Ikonos image yielded a misclassification rate of 20.3–22.7% for aquatic habitats, and 18.1–25.1% for anopheline-positive larval habitats. Conclusion One-metre spatial resolution Ikonos images combined with computer modelling based on topographic land-cover features are useful tools for identification of anopheline larval habitats, and they can be used to assist to malaria vector control in western Kenya

  9. Dusk to dawn activity patterns of anopheline mosquitoes in West Timor and Java, Indonesia.

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    Ndoen, Ermi; Wild, Clyde; Dale, Pat; Sipe, Neil; Dale, Mike

    2011-05-01

    Malaria is a serious health issue in Indonesia. We investigated the dusk to dawn anopheline mosquito activity patterns, host-seeking and resting locations in coastal plain, hilly and highland areas in West Timor and Java. Adult mosquitoes were captured landing on humans or resting in houses or animal barns. Data analyzed were: mosquito night-time activities; period of peak activity; night-time activity in specific periods of time and for mosquito resting locations. Eleven species were recorded; data were sparse for some species therefore detailed analyses were performed for four species only. In Java Anopheles vagus was common, with a bimodal pattern of high activity. In West Timor, its activity peaked around midnight. Other species with peak activity around the middle of the night were An. barbirostris and An. subpictus. Most species showed no biting and resting preference for indoors or outdoors, although An. barbirostris preferred indoors in West Timor, but outdoors in Java. An. aconitus and An. annularis preferred resting in human dwellings; An. subpictus and An. vagus preferred resting in animal barns. An. barbirostris preferred resting in human dwellings in West Timor and in animal barns in Java. The information is useful for planning the mosquito control aspect of malaria management. For example, where mosquito species have peak activity at night indoors, bednets and indoor residual spraying should reduce malaria risk, but where mosquitoes are most active outdoors, other options may be more effective.

  10. Environmental characteristics of anopheline mosquito larval habitats in a malaria endemic area in Iran

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    Moussa Soleimani-Ahmadi; Hassan Vatandoost; Ahmad-Ali Hanafi-Bojd; Mehdi Zare; Reza Safari; Abdolrasul Mojahedi; Fatemeh Poorahmad-Garbandi

    2013-01-01

    Objective: To determine the effects of environmental parameters of larval habitats on distribution and abundance of anopheline mosquitoes in Rudan county of Iran. Methods: This cross-sectional study was conducted during the mosquito breeding season from February 2010 to October 2011. The anopheline larvae were collected using the standard dipping method. The specimens were identified using a morphological-based key. Simultaneously with larval collection, environmental parameters of the larval habitats including water current and turbidity, sunlight situation, and substrate type of habitats were recorded. Water samples were taken from breeding sites during larval collection. Before collection of samples, the water temperature was measured. The water samples were analysed for turbidity, conductivity, total alkalinity, total dissolved solid, pH and ions including chloride, sulphate, calcium, and magnesium. Statistical correlation analysis and ANOVA test were used to analyze the association between environmental parameters and larval mosquito abundance. Results: In total 2 973 larvae of the genus Anopheles were collected from 25 larval habitats and identified using morphological characters. They comprised of six species:An. dthali turkhudi (3.30%), and An. apoci (1.14%). The most abundant species was An. dthali which were collected from all of the study areas. Larvae of two malaria vectors, An. dthali and An. stephensi, co-existed and collected in a wide range of habitats with different physico-chemical parameters. The most common larval habitats were man-made sites such as sand mining pools with clean and still water. The anopheline mosquitoes also preferred permanent habitats in sunlight with sandy substrates. The results indicated that there was a significant relationship between mean physico-chemical parameters such as water temperature, conductivity, total alkalinity, sulphate, chloride, and mosquito distribution and abundance. Conclusions: The results of this

  11. Malaria Situation and Anopheline Mosquitoes in Qom Province, Central Iran

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    B Farzinnia

    2010-12-01

    Methods: This study was carried out in two parts. First stage was data collection about malaria cases using recorded documents of patients in the Province health center, during 2001–2008. The second stage was entomological survey conducted by mosquito larval collection method in 4 villages with different geographical positions in 2008. Data were analyzed using Excel software. Results: Of 4456 blood slides, 10.9% out were positive. Most of cases were imported from other countries (90.4%, mainly from Afghanistan (56.5% and Pakistan (16.3%. Slide positive rate showed a maximum of 16.9% and a minimum of 2.9% in 2008 and 2007, respectively. Plasmodium vivax was causative agent of 93.75% of cases, fol­lowed by P. falciparum (6.25%. More than 15 years old age group contained the most malaria reported cases (66.7%. Two Anopheles species, An. superpictus and An. claviger were collected and identified. This is the first report of Anopheles claviger in Qom Province. Conclusion: Malaria is in the control stage in Qom Province. The rate of local transmission is very low (only 1 case, shows Anopheles superpictus, as the main malaria vector of central part of Iran, can play its role in malaria transmission in the area.

  12. Characterization of larval habitats for anopheline mosquitoes in a malarious area under elimination program in the southeast of Iran

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    Moussa Soleimani-Ahmadi; Hassan Vatandoost; Mehdi Zare

    2014-01-01

    Objective: To determine the effects of environmental characteristics of larval habitats on distribution and abundance of anopheline mosquitoes in Bashagard county, a malarious area in southeast of Iran. Methods: Larvae were collected monthly using the standard dipping method and identified using a morphological-based key. Environmental characteristics of the larval habitats were recorded. Water samples were taken from habitats during larval collection for physico-chemical characterization. Statistical analyses were performed. Results: In total 5150 anopheline larvae from 36 larval habitats were collected and identified. They comprised of six species: Anopheles culicifacies (29.36%), Anopheles moghulensis (25.20%),Anopheles dthali stephensi (5.01%). (18.02%), Anopheles superpictus (17.24%), Anopheles turkhudi (5.17%) and Anopheles The most common larval habitats were natural and clear water bodies such as riverbeds with sandy substrates and still water. Furthermore, the anopheline larvae were abundant in permanent and full sunlight habitats without vegetation and algae. Larval density was positively correlated with water temperature. Chemical characteristics including conductivity, total alkalinity, sulphate and chloride had significant effects on distribution and abundance of anopheline species.Conclusions:The result of this study indicates a correlation between some environmental characteristics and anopheline larvae abundance which can be considered for effective planning and implementing malaria elimination program in Iran.

  13. A Key to the Anophelines of Iran

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    Eugene R. Shahgudian

    1960-01-01

    Full Text Available Keys for identification of adult females and fourth instar larvae of Anopheline Mosquitoes of Iran with brief review of important literature on the Iranian Anopheline Fauna are given in this paper

  14. Abundance, biting behaviour and parous rate of anopheline mosquito species in relation to malaria incidence in gold-mining areas of southern Venezuela.

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    Moreno, J E; Rubio-Palis, Y; Páez, E; Pérez, E; Sánchez, V

    2007-12-01

    A longitudinal entomological and epidemiological study was conducted in five localities of southern Venezuela between January 1999 and April 2000 to determine the abundance, biting behaviour and parity of anopheline mosquitoes (Diptera: Culicidae) in relation to climate variables and malaria incidence. A total of 3685 female anopheline mosquitoes, representing six species, were collected. The most abundant species were Anopheles marajoara Galvão & Damasceno (60.7%) and Anopheles darlingi Root (35.1%), which together represented 95.8% of the total anophelines collected. Abundance and species distribution varied by locality. Malaria prevalence varied from 12.5 to 21.4 cases per 1000 population. Transmission occurred throughout the year; the annual parasite index (API) for the study period was 813.0 cases per 1000 population, with a range of 71.6-2492 per 1000 population, depending on locality. Plasmodium vivax (Grassi & Feletti) (Coccidia: Plasmodiidae) accounted for 78.6% of cases, Plasmodium falciparum (Welch) for 21.4% and mixed infections (Pv+Pf) for 0.05) between mosquito abundance and rainfall. Correlations between malaria incidence by parasite species and mosquito abundance were not significant (P > 0.05). Monthly parous rates were similar for An. marajoara and An. darlingi throughout the year, with two peaks that coincided with the dry-rainy transition period and the period of less rain. Peaks in the incidence of malaria cases were observed 1 month after major peaks in biting rates of parous anophelines. Anopheles darlingi engages in biting activity throughout the night, with two minor peaks at 23.00-00.00 hours and 03.00-04.00 hours. Anopheles marajoara has a different pattern, with a biting peak at 19.00-21.00 hours and 76.6% of biting occurring before midnight. Although both vectors bite indoors and outdoors, they showed a highly significant (P Venezuela and to provide relevant information to be considered when planning and implementing vector control

  15. Salivary gland proteome analysis reveals modulation of anopheline unique proteins in insensitive acetylcholinesterase resistant Anopheles gambiae mosquitoes.

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    Sylvie Cornelie

    Full Text Available Insensitive acetylcholinesterase resistance due to a mutation in the acetylcholinesterase (ace encoding ace-1 gene confers cross-resistance to organophosphate and carbamate insecticides in Anopheles gambiae populations from Central and West Africa. This mutation is associated with a strong genetic cost revealed through alterations of some life history traits but little is known about the physiological and behavioural changes in insects bearing the ace-1(R allele. Comparative analysis of the salivary gland contents between An. gambiae susceptible and ace-1(R resistant strains was carried out to charaterize factors that could be involved in modifications of blood meal process, trophic behaviour or pathogen interaction in the insecticide-resistant mosquitoes. Differential analysis of the salivary gland protein profiles revealed differences in abundance for several proteins, two of them showing major differences between the two strains. These two proteins identified as saglin and TRIO are salivary gland-1 related proteins, a family unique to anopheline mosquitoes, one of them playing a crucial role in salivary gland invasion by Plasmodium falciparum sporozoites. Differential expression of two other proteins previously identified in the Anopheles sialome was also observed. The differentially regulated proteins are involved in pathogen invasion, blood feeding process, and protection against oxidation, relevant steps in the outcome of malaria infection. Further functional studies and insect behaviour experiments would confirm the impact of the modification of the sialome composition on blood feeding and pathogen transmission abilities of the resistant mosquitoes. The data supports the hypothesis of alterations linked to insecticide resistance in the biology of the primary vector of human malaria in Africa.

  16. The fauna, monthly activity and species composition of anophelines mosquito larva in breeding places, Qom province

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    Abedin Saghafipour

    2013-09-01

    Full Text Available Background: There is need to develop updated database related to malaria mosquito, because there is back prevalence of malaria in the past two decades in some areas of north and northwest of Iran categorized as epidemiologically clean areas previously. Vectors control is one of the main strategies in controlling the epidemics. In this study, species composition and monthly activity of anopheles mosquito larva in different breeding places in Qom province was assessed. Material and Methods: The present study was a cross-sectional one. It was carried out in all 5 parts of geographical areas of Qom province. Samples were collected every 15 days from the natural and artificial breeding places from April to October 2010, using dipping standard method of WHO. Mosquito larvae conserved in lactophenol medium. In the laboratory, the specimens were mounted in likidophor medium and microscopic slides were prepared from larvae, and identified using illustrated keys for Iranian mosquitoes. Results: A total of 298 larvae samples were collected and identified from different breeding places in various areas of Qom province. This larvae belonged to two subgenus of Anopheles and Cellia and including four species of An.(Ano.marteri, An.(Ano.claviger, An.(Cel.superpictus, and An.(Cel.turkhudi. An.(Ano. claviger, An.(Ano.marteri, and An.(Cel.turkhudi are reported for the first time in this province. An.(Ano.claviger was dominant species of larvae in the breeding places in Qom province and found in different larva habitats. The peak of activity of recent species is in late July and early August and its seasonal activity is in late April to late October. Conclusion: An.(Cel.superpictus which is Malaria vector in different parts of the world and Iran is the dominant species of the area had the second frequency. Having high potential for transmission and possibility of establishing a transmission cycle with low abundance is the characteristics of first species. Anopheles

  17. Diversity of anopheline mosquitoes (Diptera: Culicidae) and classification based on the characteristics of the habitats where they were collected in Puerto Iguazú, Misiones, Argentina.

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    Ramirez, P G; Stein, M; Etchepare, E G; Almiron, W R

    2016-12-01

    In order to extend the knowledge of anopheline diversity and their habitats in three environments with different degrees of anthropic intervention in Puerto Iguazú, Misiones, anopheline larvae were collected and classified on the basis of similarities of their habitats. Spatio-temporal abundance was determined and larval diversity and complementarity index were calculated. Rank-abundance curves were performed to compare the composition, abundance, and species evenness among environments. A total of 783 larvae, belonging to six species: Anopheles argyritarsis, An. fluminensis, An. mediopunctatus, An. punctimacula, An. strodei s.l., and An. triannulatus s.l., were collected. A cluster analysis and a principal component analysis detected two groups; exposure to sunlight and type of habitat were the characteristics that explained the grouping of species. Higher abundances of anopheline larvae were observed during autumn and spring. The greatest richness was recorded in wild and peri-urban environments and the effective number of species was greater in the wild. Anopheles punctimacula and An. triannulatus s.l. are secondary vectors of malaria in other South American countries and both species were found in the three environments, so that deforestation poses a potential risk for malaria transmission as it contributes to the proliferation of larval habitats for these mosquitoes.

  18. Larvivorous potential of the guppy, Poecilia reticulata, in anopheline mosquito control in riverbed pools below the Kotmale dam, Sri Lanka.

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    Kusumawathie, P H D; Wickremasinghe, A R; Karunaweera, N D; Wijeyaratne, M J S

    2008-01-01

    The larvivorous potential of Poecilia reticulata was studied in the laboratory and in the field. In the laboratory, the number of anopheline larvae consumed per fish per day and the number of larvae in fecal matter per fish were determined. In the field study, 29 of 60 selected riverbed pools in Kotmale oya, below the Kotmale dam, were stocked with P reticulata, whereas the rest served as controls. Anopheline larval surveys were carried out starting from 1 day prior to stocking of fish and on selected days subsequently. P. reticulata consumed an average of 117 +/- 32.33 larvae per fish per day. Fecal matter of P. reticulata contained an average of 2.7 +/- 2.68 larvae per fish . There was a significant reduction in the number of pools positive for anopheline larvae (P < .001) after stocking fish and the number of larvae per pool (P < .001) and per 100 dips (P < .001) as compared with controls.

  19. Factors affecting transmission of Wuchereria bancrofti by anopheline mosquitoes. 2. Damage to ingested microfilariae by mosquito foregut armatures and development of filarial larvae in mosquitoes.

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    Bryan, J H; Southgate, B A

    1988-01-01

    Microfilariae (mf) of Wuchereria bancrofti from the midgut of 639 Anopheles gambiae, 557 An. arabiensis, 117 An. melas and 9 An. funestus were examined immediately after the mosquitoes had fed on carriers with different densities of mf. The percentages of mf damaged during ingestion were 57.1-60.0 in An. gambiae, 33.3-50.6 in An. arabiensis and 38.7-55.7 in An. melas. In each species the percentage of mf damaged was independent of mf density in the human host. A further 3657 An. gambiae, 2875 An. arabiensis, 347 An. melas and 32 An. funestus were examined 7 d or more after feeding on mf carriers. In An. gambiae and An. arabiensis, mean numbers of larvae per mosquito were strongly correlated to mf blood density, with similar regression slopes to those obtained from the regression of mf blood density on mean uptake of mf/mosquito. The ratio of mean numbers of larvae per mosquito to mean numbers of intact mf ingested per mosquito increased as the density of mf in the human host increased in An. gambiae and An. arabiensis, but decreased in An. melas as host mf density increased.

  20. Anopheline and culicine mosquitoes are not repelled by surfaces treated with the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana

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    Mnyone, L.L.; Koenraadt, C.J.M.; Lyimo, I.N.; Mpingwa, M.W.; Takken, W.; Russell, T.L.

    2010-01-01

    Background - Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana, are promising bio-pesticides for application against adult malaria mosquito vectors. An understanding of the behavioural responses of mosquitoes towards these fungi is necessary to guide development of fungi beyond t

  1. Anopheline and culicine mosquitoes are not repelled by surfaces treated with the entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana

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    Mnyone Ladslaus L

    2010-08-01

    Full Text Available Abstract Background Entomopathogenic fungi, Metarhizium anisopliae and Beauveria bassiana, are promising bio-pesticides for application against adult malaria mosquito vectors. An understanding of the behavioural responses of mosquitoes towards these fungi is necessary to guide development of fungi beyond the 'proof of concept' stage and to design suitable intervention tools. Methods Here we tested whether oil-formulations of the two fungi could be detected and avoided by adult Anopheles gambiae s.s., Anopheles arabiensis and Culex quinquefasciatus. The bioassays used a glass chamber divided into three compartments (each 250 × 250 × 250 mm: release, middle and stimulus compartments. Netting with or without fungus was fitted in front of the stimulus compartment. Mosquitoes were released and the proportion that entered the stimulus compartment was determined and compared between treatments. Treatments were untreated netting (control 1, netting with mineral oil (control 2 and fungal conidia formulated in mineral oil evaluated at three different dosages (2 × 1010, 4 × 1010 and 8 × 1010 conidia m-2. Results Neither fungal strain was repellent as the mean proportion of mosquitoes collected in the stimulus compartment did not differ between experiments with surfaces treated with and without fungus regardless of the fungal isolate and mosquito species tested. Conclusion Our results indicate that mineral-oil formulations of M. anisopliae and B. bassiana were not repellent against the mosquito species tested. Therefore, both fungi are suitable candidates for the further development of tools that aim to control host-seeking or resting mosquitoes using entomopathogenic fungi.

  2. The ecology and larval habitats characteristics of anopheline mosquitoes (Diptera:Culicidae) in Aligudarz County (Luristan province, western Iran)

    Institute of Scientific and Technical Information of China (English)

    Hamid Amani; Mohammad Reza Yaghoobi-Ershadi; Hamid Kassiri

    2014-01-01

    Objective: To determine ecology and characteristics of the larval habitats of the genus Anopheles (Dipetra: Culicidae) in Aligudarz County, western Iran.Methods:larvae ecology in seven rural districts, Aligudarz County, from late April to late November 1997. Larvae were captured using the dipping method. Larval breeding places characteristics were noted according to water situation (turbid or clean, stagnant or running), substrate type, site type (man-made or natural), sunlight situation, site situation (transient or permanent, with or without vegetation). This descriptive cross-sectional research was carried out to study the anopheline Results: A total of 9 620 3rd and 4th instar larvae of Anopheles from 115 breeding places in 22 villages were captured, which belonged to the following species: Anopheles stephensi, Anopheles d’thali, Anopheles apoci, Anopheles superpictus (forms A and B), Anopheles marterii sogdianus, Anopheles turkhodi, Anopheles maculipennis S.L and Anopheles claviger. Anopheles stephensi,Anopheles maculipennis Anopheles superpictus (93.18%) was the most prevailed one and dispersed over the entire region. Larval habitats consisted of nine natural and three artificial larval habitats. The most important larval habitats were river edges (54.8%), rice fields (12.2%), and grassland (8.7%) with permanent or transient, stagnant or running and clean water, with or without vegetation, sand or mud substrate in full sunlight area.Conclusions:Regarding this research, river edges and rice fields are the most important S.L and Anopheles apoci were collected for the first time in this county. breeding places of malaria vectors in Aligudarz County. It is worthy of note in larvicidal programs.

  3. Blood Meal Preference of Some Anopheline Mosquitoes in Command and Non-command Areas of Rajasthan, India

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    Kailash Kumar Swami

    2012-12-01

    Full Text Available Background: The present study was undertaken to compare the entomological situation by analyzing the bloodmeal of mosquitoes of canal irrigated and non-irrigated areas of Bikaner in order to explore scientific information onthe vector biology and malaria burden profile and to plan proper strategies for malaria control and eradication.Methods: Adult mosquitoes were collected and the abdomen of the blood fed females were crushed on a filter paperfor blood meal analysis and subjected to precipitin test.Results: The blood meal analysis showed that Anopheles subpictus had a preference towards cattle blood, An.culicifacies and An. stephensi preferred human blood, while, An. annularis was noted to feed only on bovine blood.Conclusion: Although An. annularis, has been recently reported from the area, was found to feed exclusively onbovine blood, earlier reports suggest that this species is a vector of malaria and therefore preventive measuresshould be taken well in advance before this species gets established in the area.

  4. An experimental hut evaluation of Olyset® nets against anopheline mosquitoes after seven years use in Tanzanian villages

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    Mosha Frank W

    2008-02-01

    Full Text Available Abstract Background Long-lasting insecticidal nets (LLINs are advocated by WHO for protection against malaria. Of the three brands of LLINs currently approved by WHO, Olyset® is the only one currently granted full recommendation. With this type of LLIN, the insecticide (permethrin is incorporated into the polyethylene fibre during manufacture and diffuses from the core to the surface, thereby maintaining surface concentrations. It has not been determined for how long Olyset nets remain protective against mosquitoes in household use. Methods Examples of Olyset nets, which had been in use in Tanzanian villages for seven years, were tested in experimental huts against naturally entering Anopheles gambiae and Anopheles funestus mosquitoes. Performance was compared with new Olyset nets, conventionally treated ITNs (either newly treated with alphacypermethrin or taken from local villages after 1.5 years of use and untreated nets. All nets were artificially holed except for the seven-year Olyset nets, which had developed holes during prolonged domestic use. Results Anopheles funestus and An. gambiae in NE Tanzania are susceptible to pyrethroids. The new Olyset nets caused high mortality against An. funestus (73.9% and An. gambiae (62.7% in experimental huts. The seven-year Olyset nets caused 58.9% mortality against An. funestus and 40.0% mortality against An. gambiae. The freshly treated alphacypermethrin nets also caused high mortality against An. funestus (70.6% and An. gambiae (72.0%; this decreased to 58.4% and 69.6% respectively after 1.5 years of use. The new Olyset nets inhibited blood-feeding by 40–50%. The 7 year Olyset nets showed no feeding inhibition over that shown by the untreated nets. The alphacypermethrin treated nets failed to inhibit blood-feeding after 1.5 years of use. However iHhhdn laboratory tunnel tests samples of all types of treated net including the 7 year Olyset inhibited blood-feeding by more than 95%. Conclusion After

  5. 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.

  6. Development of environmental tools for anopheline larval control

    OpenAIRE

    Mweresa Collins K; Imbahale Susan S; Takken Willem; Mukabana Wolfgang R

    2011-01-01

    Abstract Background Malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. Recent successes of mosquito larval control have been reported using environmental and biological tools. Here, we report the effects of shading by plants and biological control agents on the development and survival of anopheline and culicine mosquito larvae in man-made natural habitats in western Kenya. Trials consisted ...

  7. Spatial-temporal analysis of Cache Valley virus (Bunyaviridae: Orthobunyavirus) infection in anopheline and culicine mosquitoes (Diptera: Culicidae) in the northeastern United States, 1997-2012.

    Science.gov (United States)

    Andreadis, Theodore G; Armstrong, Philip M; Anderson, John F; Main, Andrew J

    2014-10-01

    Cache Valley virus (CVV) is a mosquito-borne bunyavirus (family Bunyaviridae, genus Orthobunyavirus) that is enzootic throughout much of North and Central America. White-tailed deer (Odocoileus virginianus) have been incriminated as important reservoir and amplification hosts. CVV has been found in a diverse array of mosquito species, but the principal vectors are unknown. A 16-year study was undertaken to identify the primary mosquito vectors in Connecticut, quantify seasonal prevalence rates of infection, and define the spatial geographic distribution of CVV in the state as a function of land use and white-tailed deer populations, which have increased substantially over this period. CVV was isolated from 16 mosquito species in seven genera, almost all of which were multivoltine and mammalophilic. Anopheles (An.) punctipennis was incriminated as the most consistent and likely vector in this region on the basis of yearly isolation frequencies and the spatial geographic distribution of infected mosquitoes. Other species exhibiting frequent temporal and moderate spatial geographic patterns of virus isolation within the state included Ochlerotatus (Oc.) trivittatus, Oc. canadensis, Aedes (Ae.) vexans, and Ae. cinereus. New isolation records for CVV were established for An. walkeri, Culiseta melanura, and Oc. cantator. Other species from which CVV was isolated included An. quadrimaculatus, Coquillettidia perturbans, Culex salinarius, Oc. japonicus, Oc. sollicitans, Oc. taeniorhynchus, Oc. triseriatus, and Psorophora ferox. Mosquitoes infected with CVV were equally distributed throughout urban, suburban, and rural locales, and infection rates were not directly associated with the localized abundance of white-tailed deer, possibly due to their saturation throughout the region. Virus activity in mosquitoes was episodic with no consistent pattern from year-to-year, and fluctuations in yearly seasonal infection rates did not appear to be directly impacted by overall

  8. Human exposure to anopheline mosquitoes occurs primarily indoors, even for users of insecticide-treated nets in Luangwa Valley, South-east Zambia

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    Seyoum Aklilu

    2012-05-01

    Full Text Available Abstract Background Current front line malaria vector control methods such as indoor residual spraying (IRS and long-lasting insecticidal nets (LLINs, rely upon the preference of many primary vectors to feed and/or rest inside human habitations where they can be targeted with domestically-applied insecticidal products. We studied the human biting behaviour of the malaria vector Anopheles funestus Giles and the potential malaria vector Anopheles quadriannulatus Theobald in Luangwa valley, south-east Zambia. Methods Mosquitoes were collected by human landing catch in blocks of houses with either combined use of deltamethrin-based IRS and LLINs or LLINs alone. Human behaviour data were collected to estimate how much exposure to mosquito bites indoors and outdoors occurred at various times of the night for LLIN users and non-users. Results Anopheles funestus and An. quadriannulatus did not show preference to bite either indoors or outdoors: the proportions [95% confidence interval] caught indoors were 0.586 [0.303, 0.821] and 0.624 [0.324, 0.852], respectively. However, the overwhelming majority of both species were caught at times when most people are indoors. The proportion of mosquitoes caught at a time when most people are indoors were 0.981 [0.881, 0.997] and 0.897 [0.731, 0.965], respectively, so the proportion of human exposure to both species occuring indoors was high for individuals lacking LLINs (An. funestus: 0.983 and An. quadriannulatus: 0.970, respectively. While LLIN users were better protected, more than half of their exposure was nevertheless estimated to occur indoors (An. funestus: 0.570 and An. quadriannulatus: 0.584. Conclusions The proportion of human exposure to both An. funestus and An. quadriannulatus occuring indoors was high in the area and hence both species might be responsive to further peri-domestic measures if these mosquitoes are susceptible to insecticidal products.

  9. The impact of pyrethroid resistance on the efficacy of insecticide-treated bed nets against African anopheline mosquitoes: systematic review and meta-analysis.

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    Clare Strode

    2014-03-01

    Full Text Available Pyrethroid insecticide-treated bed nets (ITNs help contribute to reducing malaria deaths in Africa, but their efficacy is threatened by insecticide resistance in some malaria mosquito vectors. We therefore assessed the evidence that resistance is attenuating the effect of ITNs on entomological outcomes.We included laboratory and field studies of African malaria vectors that measured resistance at the time of the study and used World Health Organization-recommended impregnation regimens. We reported mosquito mortality, blood feeding, induced exophily (premature exit of mosquitoes from the hut, deterrence, time to 50% or 95% knock-down, and percentage knock-down at 60 min. Publications were searched from 1 January 1980 to 31 December 2013 using MEDLINE, Cochrane Central Register of Controlled Trials, Science Citation Index Expanded, Social Sciences Citation Index, African Index Medicus, and CAB Abstracts. We stratified studies into three levels of insecticide resistance, and ITNs were compared with untreated bed nets (UTNs using the risk difference (RD. Heterogeneity was explored visually and statistically. Included were 36 laboratory and 24 field studies, reported in 25 records. Studies tested and reported resistance inconsistently. Based on the meta-analytic results, the difference in mosquito mortality risk for ITNs compared to UTNs was lower in higher resistance categories. However, mortality risk was significantly higher for ITNs compared to UTNs regardless of resistance. For cone tests: low resistance, risk difference (RD 0.86 (95% CI 0.72 to 1.01; moderate resistance, RD 0.71 (95% CI 0.53 to 0.88; high resistance, RD 0.56 (95% CI 0.17 to 0.95. For tunnel tests: low resistance, RD 0.74 (95% CI 0.61 to 0.87; moderate resistance, RD 0.50 (95% CI 0.40 to 0.60; high resistance, RD 0.39 (95% CI 0.24 to 0.54. For hut studies: low resistance, RD 0.56 (95% CI 0.43 to 0.68; moderate resistance, RD 0.39 (95% CI 0.16 to 0.61; high resistance, RD 0

  10. Development of environmental tools for anopheline larval control

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    Mweresa Collins K

    2011-07-01

    Full Text Available Abstract Background Malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. Recent successes of mosquito larval control have been reported using environmental and biological tools. Here, we report the effects of shading by plants and biological control agents on the development and survival of anopheline and culicine mosquito larvae in man-made natural habitats in western Kenya. Trials consisted of environmental manipulation using locally available plants, the introduction of predatory fish and/or the use of Bacillus thuringiensis var. israelensis (Bti in various combinations. Results Man-made habitats provided with shade from different crop species produced significantly fewer larvae than those without shade especially for the malaria vector Anopheles gambiae. Larval control of the African malaria mosquito An. gambiae and other mosquito species was effective in habitats where both predatory fish and Bti were applied, than where the two biological control agents were administered independently. Conclusion We conclude that integration of environmental management techniques using shade-providing plants and predatory fish and/or Bti are effective and sustainable tools for the control of malaria and other mosquito-borne disease vectors.

  11. Adult anopheline ecology and malaria transmission in irrigated areas of South Punjab, Pakistan

    DEFF Research Database (Denmark)

    Herrel, N; Amerasinghe, F P; Ensink, J

    2004-01-01

    . Anopheles stephensi, An. culicifacies and An. subpictus populations peaked in August, September and October, respectively. High temperatures and low rainfall negatively affected seasonal abundance in our area. There were interesting differences in anopheline fauna between villages, with An. culicifacies......: Culicidae) could be related to malaria transmission in rural areas with intensive irrigation and a history of malaria epidemics. In this paper we present our observations from three villages located along an irrigation canal in South Punjab. The study was carried out from 1 April 1999 to 31 March 2000....... pulcherrimus Theobald (1.0%) and An. peditaeniatus Leicester (0.1%). Most mosquitoes (98.8%) were collected from indoor resting-sites whereas collections from potential resting-sites outdoors accounted for only 1.2% of total anopheline densities, confirming the endophilic behaviour of anophelines in Pakistan...

  12. Anopheline (Diptera:Culicidae) breeding in a traditional tank-based village ecosystem in north central Sri Lanka

    DEFF Research Database (Denmark)

    Amerasinghe, F P; Konradsen, F; Fonseka, K T;

    1997-01-01

    A 13-mo survey of immature anopheline mosquitoes breeding in surface water habitats was done at Mahameegaswewa village within the Huruluwewa watershed in north central Sri Lanka as part of a multidisciplinary study on malaria epidemiology. The watershed is representative of the ancient small tank...

  13. Impact of dams and irrigation schemes in Anopheline (Diptera: Culicidae) bionomics and malaria epidemiology

    OpenAIRE

    Jordi Sanchez-Ribas; Gabriel Parra-Henao; Anthony Érico Guimarães

    2012-01-01

    Irrigation schemes and dams have posed a great concern on public health systems of several countries, mainly in the tropics. The focus of the present review is to elucidate the different ways how these human interventions may have an effect on population dynamics of anopheline mosquitoes and hence, how local malaria transmission patterns may be changed. We discuss different studies within the three main tropical and sub-tropical regions (namely Africa, Asia and the Pacific and the Americas). ...

  14. Aspects of the ecology of mosquitoes in Surinam

    NARCIS (Netherlands)

    Kruijf, de H.A.M.

    1972-01-01

    For about two years (1967—1968) investigations were conducted on the ecology of mosquitoes in relation to the transmission of arboviruses in Surinam (DE KRUIJF 1970). Part of this study dealing with the daily activity of biting mosquitoes is presented here. Daily activity of biting anopheline female

  15. Visión estudiantil de la recta y continuidad

    OpenAIRE

    Alvarado, Martha; García, Carlos

    2005-01-01

    Dentro del curso de Cálculo Diferencial e Integral del nivel superior, correspondiente a Matemáticas I de Ingeniería y Matemáticas II de la carrera de Informática, se presenta en la primera unidad el estudio de los Números Reales. El objetivo de esta unidad, es comprender las propiedades axiomáticas de los números reales, para que desde ellas se pueda formalizar el estudio del cálculo. El presente estudio pretende estudiar como el estudiante “ve” a la recta, en el momento en que se axiomatiza...

  16. Caspar controls resistance to Plasmodium falciparum in diverse anopheline species.

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    Lindsey S Garver

    2009-03-01

    Full Text Available Immune responses mounted by the malaria vector Anopheles gambiae are largely regulated by the Toll and Imd (immune deficiency pathways via the NF-kappaB transcription factors Rel1 and Rel2, which are controlled by the negative regulators Cactus and Caspar, respectively. Rel1- and Rel2-dependent transcription in A. gambiae has been shown to be particularly critical to the mosquito's ability to manage infection with the rodent malaria parasite Plasmodium berghei. Using RNA interference to deplete the negative regulators of these pathways, we found that Rel2 controls resistance of A. gambiae to the human malaria parasite Plasmodium falciparum, whereas Rel 1 activation reduced infection levels. The universal relevance of this defense system across Anopheles species was established by showing that caspar silencing also prevents the development of P. falciparum in the major malaria vectors of Asia and South America, A. stephensi and A. albimanus, respectively. Parallel studies suggest that while Imd pathway activation is most effective against P. falciparum, the Toll pathway is most efficient against P. berghei, highlighting a significant discrepancy between the human pathogen and its rodent model. High throughput gene expression analyses identified a plethora of genes regulated by the activation of the two Rel factors and revealed that the Toll pathway played a more diverse role in mosquito biology than the Imd pathway, which was more immunity-specific. Further analyses of key anti-Plasmodium factors suggest they may be responsible for the Imd pathway-mediated resistance phenotype. Additionally, we found that the fitness cost caused by Rel2 activation through caspar gene silencing was undetectable in sugar-fed, blood-fed, and P. falciparum-infected female A. gambiae, while activation of the Toll pathway's Rel1 had a major impact. This study describes for the first time a single gene that influences an immune mechanism that is able to abort

  17. Caspar controls resistance to Plasmodium falciparum in diverse anopheline species.

    Science.gov (United States)

    Garver, Lindsey S; Dong, Yuemei; Dimopoulos, George

    2009-03-01

    Immune responses mounted by the malaria vector Anopheles gambiae are largely regulated by the Toll and Imd (immune deficiency) pathways via the NF-kappaB transcription factors Rel1 and Rel2, which are controlled by the negative regulators Cactus and Caspar, respectively. Rel1- and Rel2-dependent transcription in A. gambiae has been shown to be particularly critical to the mosquito's ability to manage infection with the rodent malaria parasite Plasmodium berghei. Using RNA interference to deplete the negative regulators of these pathways, we found that Rel2 controls resistance of A. gambiae to the human malaria parasite Plasmodium falciparum, whereas Rel 1 activation reduced infection levels. The universal relevance of this defense system across Anopheles species was established by showing that caspar silencing also prevents the development of P. falciparum in the major malaria vectors of Asia and South America, A. stephensi and A. albimanus, respectively. Parallel studies suggest that while Imd pathway activation is most effective against P. falciparum, the Toll pathway is most efficient against P. berghei, highlighting a significant discrepancy between the human pathogen and its rodent model. High throughput gene expression analyses identified a plethora of genes regulated by the activation of the two Rel factors and revealed that the Toll pathway played a more diverse role in mosquito biology than the Imd pathway, which was more immunity-specific. Further analyses of key anti-Plasmodium factors suggest they may be responsible for the Imd pathway-mediated resistance phenotype. Additionally, we found that the fitness cost caused by Rel2 activation through caspar gene silencing was undetectable in sugar-fed, blood-fed, and P. falciparum-infected female A. gambiae, while activation of the Toll pathway's Rel1 had a major impact. This study describes for the first time a single gene that influences an immune mechanism that is able to abort development of P. falciparum

  18. La recta en el aprendizaje de los números negativos

    OpenAIRE

    Bruno, Alicia; Martinon, Antonio

    1994-01-01

    El papel de la recta en el aprendizaje de los números ha sido estudiado por diferentes autores. entre ellos, Ernest (1985) distingue tres usos principales que tiene la recta en la enseñanza primaria: como un modelo de enseñanza o ayuda para ordenar números, como un modelo para las cuatro operaciones básicas, y como contenido mismo del curriculum de matemáticas. En este trabajo nos centramos, principalmente, en el segundo uso de la recta citado por Ernest.

  19. Phylogeny of anopheline (Diptera: Culicidae) species in southern Africa, based on nuclear and mitochondrial genes.

    Science.gov (United States)

    Norris, Laura C; Norris, Douglas E

    2015-06-01

    A phylogeny of anthropophilic and zoophilic anopheline mosquito species was constructed, using the nuclear internal transcribed spacer 2 (ITS2) and mitochondrial cytochrome oxidase subunit I (COI) genes. The ITS2 alignment, typically difficult due to its noncoding nature and large size variations, was aided by using predicted secondary structure, making this phylogenetically useful gene more amenable to investigation. This phylogeny is unique in explicitly including zoophilic, non-vector anopheline species in order to illustrate their relationships to malaria vectors. Two new, cryptic species, Anopheles funestus-like and Anopheles rivulorum-like, were found to be present in Zambia for the first time. Sequences from the D3 region of the 28S rDNA suggest that the Zambian An. funestus-like may be a hybrid or geographical variant of An. funestus-like, previously reported in Malawi. This is the first report of An. rivulorum-like sympatric with An. rivulorum (Leeson), suggesting that these are separate species rather than geographic variants.

  20. Bionomics of Anopheline species and malaria transmission dynamics along an altitudinal transect in Western Cameroon

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    Toto Jean-Claude

    2010-05-01

    Full Text Available Abstract Background Highland areas of Africa are mostly malaria hypoendemic, due to climate which is not appropriate for anophelines development and their reproductive fitness. In view of designing a malaria control strategy in Western Cameroon highlands, baseline data on anopheline species bionomics were collected. Methods Longitudinal entomological surveys were conducted in three localities at different altitudinal levels. Mosquitoes were captured when landing on human volunteers and by pyrethrum spray catches. Sampled Anopheles were tested for the presence of Plasmodium circumsporozoite proteins and their blood meal origin with ELISA. Entomological parameters of malaria epidemiology were assessed using Mac Donald's formula. Results Anopheline species diversity and density decreased globally from lowland to highland. The most aggressive species along the altitudinal transect was Anopheles gambiae s.s. of S molecular form, followed in the lowland and on the plateau by An. funestus, but uphill by An. hancocki. An. gambiae and An. ziemanni exhibited similar seasonal biting patterns at the different levels, whereas different features were observed for An. funestus. Only indoor resting species could be captured uphill; it is therefore likely that endophilic behaviour is necessary for anophelines to climb above a certain threshold. Of the ten species collected along the transect, only An. gambiae and An. funestus were responsible for malaria transmission, with entomological inoculation rates (EIR of 90.5, 62.8 and zero infective bites/human/year in the lowland, on the plateau and uphill respectively. The duration of gonotrophic cycle was consistently one day shorter for An. gambiae as compared to An. funestus at equal altitude. Altitudinal climate variations had no effect on the survivorship and the subsequent life expectancy of the adult stage of these malaria vectors, but most probably on aquatic stages. On the contrary increasing altitude

  1. Impact of dams and irrigation schemes in Anopheline (Diptera: Culicidae bionomics and malaria epidemiology

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    Jordi Sanchez-Ribas

    2012-08-01

    Full Text Available Irrigation schemes and dams have posed a great concern on public health systems of several countries, mainly in the tropics. The focus of the present review is to elucidate the different ways how these human interventions may have an effect on population dynamics of anopheline mosquitoes and hence, how local malaria transmission patterns may be changed. We discuss different studies within the three main tropical and sub-tropical regions (namely Africa, Asia and the Pacific and the Americas. Factors such as pre-human impact malaria epidemiological patterns, control measures, demographic movements, human behaviour and local Anopheles bionomics would determine if the implementation of an irrigation scheme or a dam will have negative effects on human health. Some examples of successful implementation of control measures in such settings are presented. The use of Geographic Information System as a powerful tool to assist on the study and control of malaria in these scenarios is also highlighted.

  2. Mosquito Control

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    ... Share Facebook Twitter Google+ Pinterest Contact Us Mosquito Control About Mosquitoes General Information Life Cycle Information from ... Repellent that is Right for You DEET Mosquito Control Methods Success in mosquito control: an integrated approach ...

  3. Sentidos de uso del cero y la negatividad en la recta numérica

    OpenAIRE

    Hernández, Abraham; Gallardo, Aurora

    2009-01-01

    En este artículo se reporta un estudio realizado con 40 estudiantes, donde se manifiestan diferentes sentidos de uso del cero como origen, vía tres situaciones: primera, un punto fijo arbitrario localizado sobre la recta numérica; segunda, un punto móvil arbitrario que cambia de ubicación; tercera, un punto fijo inamovible, esto es el punto medio de la recta numérica. Así mismo, surgió el evitamiento del cero origen cuando: fue simbolizado pero ignorado al llevar a cabo las operaciones y cua...

  4. Sympathetic nerve-derived ATP regulates renal medullary blood flow via vasa recta pericytes

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    Scott S Wildman

    2013-10-01

    Full Text Available Pericyte cells are now known to be a novel locus of blood flow control, being able to regulate capillary diameter via their unique morphology and expression of contractile proteins. We have previously shown that exogenous ATP causes constriction of vasa recta via renal pericytes, acting at a variety of membrane bound P2 receptors on descending vasa recta, and therefore may be able to regulate medullary blood flow (MBF. Regulation of MBF is essential for appropriate urine concentration and providing essential oxygen and nutrients to this region of high, and variable, metabolic demand. Various sources of endogenous ATP have been proposed, including from epithelial, endothelial and red blood cells in response to stimuli such as mechanical stimulation, local acidosis, hypoxia, and exposure to various hormones. Extensive sympathetic innervation of the nephron has previously been shown, however the innervation reported has focused around the proximal and distal tubules, and ascending loop of Henle. We hypothesise that sympathetic nerves are an additional source of ATP acting at renal pericytes and therefore regulate MBF. Using a rat live kidney slice model in combination with video imaging and confocal microscopy techniques we firstly show sympathetic nerves in close proximity to vasa recta pericytes in both the outer and inner medulla. Secondly, we demonstrate pharmacological stimulation of sympathetic nerves in situ (by tyramine evokes pericyte-mediated vasoconstriction of vasa recta capillaries; inhibited by the application of the P2 receptor antagonist suramin. Lastly, tyramine-evoked vasoconstriction of vasa recta by pericytes is significantly less than ATP-evoked vasoconstriction. Sympathetic innervation may provide an additional level of functional regulation in the renal medulla that is highly localized. It now needs to be determined under which physiological/pathophysiological circumstances that sympathetic innervation of renal pericytes is

  5. 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...

  6. The phenology of malaria mosquitos in irrigated rice fields in Mali

    NARCIS (Netherlands)

    Klinkenberg, E.; Takken, W.; Huibers, F.P.; Touré, Y.T.

    2003-01-01

    A field study was carried out in the large-scale rice irrigation scheme of the Office du Niger in Mali to investigate the relation between anopheline mosquito larval development and small-scale differences in irrigation practices, such as water level, irrigation application and irrigation frequency.

  7. Anopheline larval habitats seasonality and species distribution: a prerequisite for effective targeted larval habitats control programmes.

    Directory of Open Access Journals (Sweden)

    Eliningaya J Kweka

    Full Text Available BACKGROUND: Larval control is of paramount importance in the reduction of malaria vector abundance and subsequent disease transmission reduction. Understanding larval habitat succession and its ecology in different land use managements and cropping systems can give an insight for effective larval source management practices. This study investigated larval habitat succession and ecological parameters which influence larval abundance in malaria epidemic prone areas of western Kenya. METHODS AND FINDINGS: A total of 51 aquatic habitats positive for anopheline larvae were surveyed and visited once a week for a period of 85 weeks in succession. Habitats were selected and identified. Mosquito larval species, physico-chemical parameters, habitat size, grass cover, crop cycle and distance to nearest house were recorded. Polymerase chain reaction revealed that An. gambiae s.l was the most dominant vector species comprised of An.gambiae s.s (77.60% and An.arabiensis (18.34%, the remaining 4.06% had no amplification by polymerase chain reaction. Physico-chemical parameters and habitat size significantly influenced abundance of An. gambiae s.s (P = 0.024 and An. arabiensis (P = 0.002 larvae. Further, larval species abundance was influenced by crop cycle (P≤0.001, grass cover (P≤0.001, while distance to nearest houses significantly influenced the abundance of mosquito species larvae (r = 0.920;P≤0.001. The number of predator species influenced mosquito larval abundance in different habitat types. Crop weeding significantly influenced with the abundance of An.gambiae s.l (P≤0.001 when preceded with fertilizer application. Significantly higher anopheline larval abundance was recorded in habitats in pasture compared to farmland (P = 0.002. When habitat stability and habitat types were considered, hoof print were the most productive followed by disused goldmines. CONCLUSION: These findings suggest that implementation of effective larval

  8. Risk factors for mosquito house entry in the Lao PDR.

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    Alexandra Hiscox

    Full Text Available BACKGROUND: Construction of the Nam Theun 2 hydroelectric project and flooding of a 450 km(2 area of mountain plateau in south-central Lao PDR resulted in the resettlement of 6,300 people to newly built homes. We examined whether new houses would have altered risk of house entry by mosquitoes compared with traditional homes built from poorer construction materials. METHODOLOGY/PRINCIPAL FINDINGS: Surveys were carried out in the Nam Theun 2 resettlement area and a nearby traditional rice farming area in 2010. Mosquitoes were sampled in bedrooms using CDC light traps in 96 resettlement houses and 96 traditional houses and potential risk factors for mosquito house entry were recorded. Risk of mosquito house entry was more than twice as high in traditional bamboo houses compared with those newly constructed from wood (Putative Japanese Encephalitis (JE vector incidence rate ratio (IRR = 2.26, 95% CI 1.38-3.70, P = 0.001; Anopheline IRR = 2.35, 95% CI: 1.30-4.23, P = 0.005. Anophelines were more common in homes with cattle compared against those without (IRR = 2.32, 95% CI: 1.29-4.17, P = 0.005.Wood smoke from cooking fires located under the house or indoors was found to be protective against house entry by both groups of mosquito, compared with cooking in a separate room beside the house (Putative JE vector IRR = 0.43, 95% CI: 0.26-0.73, P = 0.002; Anopheline IRR = 0.22, 95% CI: 0.10-0.51, P<0.001. CONCLUSIONS/SIGNIFICANCE: Construction of modern wooden homes should help reduce human-mosquito contact in the Lao PDR. Reduced mosquito contact rates could lead to reduced transmission of diseases such as JE and malaria. Cattle ownership was associated with increased anopheline house entry, so zooprophylaxis for malaria control is not recommended in this area. Whilst wood smoke was protective against putative JE vector and anopheline house entry we do not recommend indoor cooking since smoke inhalation can enhance

  9. Mosquito Vectors and the Globalization of Plasmodium falciparum Malaria.

    Science.gov (United States)

    Molina-Cruz, Alvaro; Zilversmit, Martine M; Neafsey, Daniel E; Hartl, Daniel L; Barillas-Mury, Carolina

    2016-11-23

    Plasmodium falciparum malaria remains a devastating public health problem. Recent discoveries have shed light on the origin and evolution of Plasmodium parasites and their interactions with their vertebrate and mosquito hosts. P. falciparum malaria originated in Africa from a single horizontal transfer between an infected gorilla and a human, and became global as the result of human migration. Today, P. falciparum malaria is transmitted worldwide by more than 70 different anopheline mosquito species. Recent studies indicate that the mosquito immune system can be a barrier to malaria transmission and that the P. falciparum Pfs47 gene allows the parasite to evade mosquito immune detection. Here, we review the origin and globalization of P. falciparum and integrate this history with analysis of the biology, evolution, and dispersal of the main mosquito vectors. This new perspective broadens our understanding of P. falciparum population structure and the dispersal of important parasite genetic traits.

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

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    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.

  11. Textual alchemy: the transformation of pseudo-Albertus Magnus's Semita recta into the Mirror of Lights.

    Science.gov (United States)

    Grund, Peter

    2009-11-01

    This article explores the strategies of and the reasons behind the reworking of pseudo-Albertus Magnus's Semita recta into the Mirror of Lights. I argue that the redactor sought to provide a more comprehensive defence of the legitimacy of alchemy than found in the Semita recta. In the process of doing so, he reshaped the original text so as to present three units that addressed different parts of the alchemical opus: first, theory and justification of alchemy; second, basic information on substances and procedures; and, third, practice. The redactor employed sophisticated textual tools identical to those seen in scholastic texts. These strategies, I argue, constitute part of the redactor's attempt to bring authority and credibility to his project and to alchemy in general. Certainly, much more attention needs to be paid to these experiments of textual alchemy in order to understand the practice of alchemy in the late medieval period.

  12. Hemolytic C-type lectin CEL-III from sea cucumber expressed in transgenic mosquitoes impairs malaria parasite development.

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    Shigeto Yoshida

    2007-12-01

    Full Text Available The midgut environment of anopheline mosquitoes plays an important role in the development of the malaria parasite. Using genetic manipulation of anopheline mosquitoes to change the environment in the mosquito midgut may inhibit development of the malaria parasite, thus blocking malaria transmission. Here we generate transgenic Anopheles stephensi mosquitoes that express the C-type lectin CEL-III from the sea cucumber, Cucumaria echinata, in a midgut-specific manner. CEL-III has strong and rapid hemolytic activity toward human and rat erythrocytes in the presence of serum. Importantly, CEL-III binds to ookinetes, leading to strong inhibition of ookinete formation in vitro with an IC(50 of 15 nM. Thus, CEL-III exhibits not only hemolytic activity but also cytotoxicity toward ookinetes. In these transgenic mosquitoes, sporogonic development of Plasmodium berghei is severely impaired. Moderate, but significant inhibition was found against Plasmodium falciparum. To our knowledge, this is the first demonstration of stably engineered anophelines that affect the Plasmodium transmission dynamics of human malaria. Although our laboratory-based research does not have immediate applications to block natural malaria transmission, these findings have significant implications for the generation of refractory mosquitoes to all species of human Plasmodium and elucidation of mosquito-parasite interactions.

  13. Metagenomics, paratransgenesis and the Anopheles microbiome: a portrait of the geographical distribution of the anopheline microbiota based on a meta-analysis of reported taxa.

    Science.gov (United States)

    Villegas, Luis Martínez; Pimenta, Paulo Filemon Paolucci

    2014-08-01

    Anophelines harbour a diverse microbial consortium that may represent an extended gene pool for the host. The proposed effects of the insect microbiota span physiological, metabolic and immune processes. Here we synthesise how current metagenomic tools combined with classical culture-dependent techniques provide new insights in the elucidation of the role of the Anopheles-associated microbiota. Many proposed malaria control strategies have been based upon the immunomodulating effects that the bacterial components of the microbiota appear to exert and their ability to express anti-Plasmodium peptides. The number of identified bacterial taxa has increased in the current "omics" era and the available data are mostly scattered or in "tables" that are difficult to exploit. Published microbiota reports for multiple anopheline species were compiled in an Excel® spreadsheet. We then filtered the microbiota data using a continent-oriented criterion and generated a visual correlation showing the exclusive and shared bacterial genera among four continents. The data suggested the existence of a core group of bacteria associated in a stable manner with their anopheline hosts. However, the lack of data from Neotropical vectors may reduce the possibility of defining the core microbiota and understanding the mosquito-bacteria interactive consortium.

  14. Biting Indices, Host-seeking Activity and Natural Infection Rates of Anopheline Species in Boa Vista, Roraima, Brazil from 1996 to 1998

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    Silva-Vasconcelos Adenildo da

    2002-01-01

    Full Text Available The epidemiology of the transmission of malaria parasites varies ecologically. To observe some entomological aspects of the malaria transmission in an urban environment, a longitudinal survey of anopheline fauna was performed in Boa Vista, Roraima, Brazil. A total of 7,263 anophelines was collected in human bait at 13 de Setembro and Caranã districts: Anopheles albitarsis sensu lato (82.8%, An. darlingi (10.3%, An. braziliensis (5.5%, An. peryassui (0.9% and An. nuneztovari (0.5%. Nightly 12 h collections showed that An. albitarsis was actively biting throughout the night with peak activities at sunset and at midnight. An. darlingi bit during all night and did not demonstrate a defined biting peak. Highest biting indices, entomological inoculation rates and malaria cases were observed seasonally during the rainy season (April-November. Hourly collections showed host seek activity for all mosquitoes peaked during the first hour after sunset. An. darlingi showed the highest plasmodial malaria infection rate followed by An. albitarsis, An. braziliensis and An. nuneztovari (8.5%, 4.6%, 3% and 2.6%, respectively. An. albitarsis was the most frequently collected anopheline, presented the highest biting index and it was the second most frequently collected infected species infected with malaria parasites. An. albitarsis and An. darlingi respectively, are the primary vectors of malaria throughout Boa Vista.

  15. Metagenomics, paratransgenesis and the Anopheles microbiome: a portrait of the geographical distribution of the anopheline microbiota based on a meta-analysis of reported taxa

    Directory of Open Access Journals (Sweden)

    Luis Martínez Villegas

    2014-08-01

    Full Text Available Anophelines harbour a diverse microbial consortium that may represent an extended gene pool for the host. The proposed effects of the insect microbiota span physiological, metabolic and immune processes. Here we synthesise how current metagenomic tools combined with classical culture-dependent techniques provide new insights in the elucidation of the role of the Anopheles-associated microbiota. Many proposed malaria control strategies have been based upon the immunomodulating effects that the bacterial components of the microbiota appear to exert and their ability to express anti-Plasmodium peptides. The number of identified bacterial taxa has increased in the current “omics” era and the available data are mostly scattered or in “tables” that are difficult to exploit. Published microbiota reports for multiple anopheline species were compiled in an Excel® spreadsheet. We then filtered the microbiota data using a continent-oriented criterion and generated a visual correlation showing the exclusive and shared bacterial genera among four continents. The data suggested the existence of a core group of bacteria associated in a stable manner with their anopheline hosts. However, the lack of data from Neotropical vectors may reduce the possibility of defining the core microbiota and understanding the mosquito-bacteria interactive consortium.

  16. Glycogen accumulation in the pars recta of the proximal tubule in Fanconi syndrome.

    Science.gov (United States)

    Bendon, R W; Hug, G

    1986-01-01

    We reviewed the renal pathology in 10 cases of renal Fanconi syndrome. Five cases showed the Armanni-Ebstein lesion, i.e., clear glycogen-filled cells limited to the pars recta of the proximal tubules. The 5 cases included 2 siblings with a unique syndrome characterized by death in infancy, severe Fanconi syndrome, severe rickets, carnitine deficiency, and atrophy of the exocrine pancreas. Two other siblings had glycogen storage disease type XI. One of 4 cases of putative tyrosinemia had the lesion. The ultrastructure was studied in 2 cases. The Armanni-Ebstein lesion in these cases was morphologically indistinguishable from that seen in diabetic patients dying after prolonged hyperglycemia. Glycosuria is the only common factor in both diabetic hyperglycemia and the varied proximal tubular diseases studied. The mechanism of the glycogen accumulation in this short parts recta segment of the proximal renal tubule was further investigated by reviewing the renal histology in cases of glycogen storage disease types I, II, III, and VIII. None showed the Armanni-Ebstein lesion, but type I showed glycogen deposition throughout the proximal tubule. Thus, the Armanni-Ebstein lesion is not the result of an enzymatic deficiency for glycogen synthesis in the convoluted tubules.

  17. Transgenic malaria-resistant mosquitoes have a fitness advantage when feeding on Plasmodium-infected blood.

    Science.gov (United States)

    Marrelli, Mauro T; Li, Chaoyang; Rasgon, Jason L; Jacobs-Lorena, Marcelo

    2007-03-27

    The introduction of genes that impair Plasmodium development into mosquito populations is a strategy being considered for malaria control. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this approach. We have previously shown that anopheline mosquitoes expressing the SM1 peptide in the midgut lumen are impaired for transmission of Plasmodium berghei. Moreover, the transgenic mosquitoes had no noticeable fitness load compared with nontransgenic mosquitoes when fed on noninfected mice. Here we show that when fed on mice infected with P. berghei, these transgenic mosquitoes are more fit (higher fecundity and lower mortality) than sibling nontransgenic mosquitoes. In cage experiments, transgenic mosquitoes gradually replaced nontransgenics when mosquitoes were maintained on mice infected with gametocyte-producing parasites (strain ANKA 2.34) but not when maintained on mice infected with gametocyte-deficient parasites (strain ANKA 2.33). These findings suggest that when feeding on Plasmodium-infected blood, transgenic malaria-resistant mosquitoes have a selective advantage over nontransgenic mosquitoes. This fitness advantage has important implications for devising malaria control strategies by means of genetic modification of mosquitoes.

  18. Composite fish culture for mosquito control in rice fields in southern India.

    Science.gov (United States)

    Victor, T J; Chandrasekaran, B; Reuben, R

    1994-09-01

    Composite culture of edible fishes (common carp, Cryprinus carpio; silver carp, Hypopthalmithys molitrix, grass carp, Ctenopharyngodon idella; catla, Catla catla; rohu, Labeo rohita; and mrigal, Cirrhinus mrigala) in rice fields in the Cauvery delta of Tamil Nadu, southern India, resulted in 81.0% reduction in the immature mosquito population of anophelines and 83.5% of culicines. Analysis of fish feces for mosquito larval head capsules showed that common carp and silver carp are effective larvivores. The selective feeding of common carp on culicines and silver carp on anophelines is correlated to their trophic niches. Net profit in the fish-cum-rice fields was 2.5 times greater than fields in which rice alone was cultured. Hence, rice-cum-fish culture can be recommended to the farming community in this area.

  19. Mosquito cell line glycoproteins: an unsuitable model system for the Plasmodium ookinete-mosquito midgut interaction?

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    Wilkins Simon

    2010-03-01

    Full Text Available Abstract Background Mosquito midgut glycoproteins may act as key recognition sites for the invading malarial ookinete. Effective transmission blocking strategies require the identification of novel target molecules. We have partially characterised the surface glycoproteins of two cell lines from two mosquito species; Anopheles stephensi and Anopheles gambiae, and investigated the binding of Plasmodium berghei ookinetes to carbohydrate ligands on the cells. Cell line extracts were run on SDS-PAGE gels and carbohydrate moieties determined by blotting against a range of biotinylated lectins. In addition, specific glycosidases were used to cleave the oligosaccharides. Results An. stephensi 43 and An. gambiae 55 cell line glycoproteins expressed oligosaccharides containing oligomannose and hybrid oligosaccharides, with and without α1-6 core fucosylation; N-linked oligosaccharides with terminal Galβ1-3GalNAc or GalNAcβ1-3Gal; O-linked α/βGalNAc. An. stephensi 43 cell line glycoproteins also expressed N-linked Galβ1-4R and O-linked Galβ1-3GalNAc. Although P. berghei ookinetes bound to both mosquito cell lines, binding could not be inhibited by GlcNAc, GalNAc or Galactose. Conclusions Anopheline cell lines displayed a limited range of oligosaccharides. Differences between the glycosylation patterns of the cell lines and mosquito midgut epithelial cells could be a factor why ookinetes did not bind in a carbohydrate inhibitable manner. Anopheline cell lines are not suitable as a potential model system for carbohydrate-mediated adhesion of Plasmodium ookinetes.

  20. Development of environmental tools for anopheline larval control

    NARCIS (Netherlands)

    Imbahale, S.S.; Mweresa, C.K.; Takken, W.; Mukabana, W.R.

    2011-01-01

    Background: Malaria mosquitoes spend a considerable part of their life in the aquatic stage, rendering them vulnerable to interventions directed to aquatic habitats. Recent successes of mosquito larval control have been reported using environmental and biological tools. Here, we report the effects o

  1. A REVIEW OF ANOPHELINE MOSQUITOES AND MALARIA CONTROL STRATEGIES IN IRIAN JAYA, INDONESIA

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    Cole J. Church

    2012-09-01

    Full Text Available Bionomik dan peran sebagai vektor keduapuluh dua spesies nyamuk yang ditemukan di Irian Jaya, sudah diulas. Kelompok punctulatus yang semula dilaporkan hanya terdiri dari 5 spesies, saat ini diperkirakan paling sedikit terdiri dari 11 spesies. Kelompok spesies ini adalah vektor malaria yang paling dominan di wilayah Australoasia, meskipun spesies-spesies lain yang ditemukan juga cukup penting. Kunci elektroforesis untuk kelompok punctulatus sudah ada acuannya. Ulasan singkat dan diskusi mengenai strategi pengendalian malaria sudah dilakukan. Program ini umumnya memiliki ciri khas tertentu. Ini ditemukan di negara-negara yang pertumbuhan sosial ekonomi, perangkat pelayanan kesehatan dan tingkat pendidikannya sedang berkembang dan program-program ini difokuskan pada peran serta masyarakat dan strategi pengendalian jentik secara berkesinambungan. Dalam jangka panjang, strategi yang bisa menunjang penurunan populasi vektor di Irian Jaya didiskusikan dengan titik berat pada peran serta masyarakat dan pendidikan, koordinasi pengendalian malaria dengan pengaturan pertanian, meningkatkan ketergantungan pada pengendalian jentik secara berkesinambungan dan melibatkan aparat kesehatan setempat sebagai bagian tak terpisahkan dari program pengendalian malaria di pedesaan. Diharapkan ulasan ini akan memberikan nilai tambah kepustakaan bagi para entomologiwan yang bekerja di daerah.

  2. A sensitive, specific and reproducible real-time polymerase chain reaction method for detection of Plasmodium vivax and Plasmodium falciparum infection in field-collected anophelines.

    Science.gov (United States)

    Bickersmith, Sara A; Lainhart, William; Moreno, Marta; Chu, Virginia M; Vinetz, Joseph M; Conn, Jan E

    2015-06-01

    We describe a simple method for detection of Plasmodium vivax and Plasmodium falciparum infection in anophelines using a triplex TaqMan real-time polymerase chain reaction (PCR) assay (18S rRNA). We tested the assay on Anopheles darlingi and Anopheles stephensi colony mosquitoes fed with Plasmodium-infected blood meals and in duplicate on field collected An. darlingi. We compared the real-time PCR results of colony-infected and field collected An. darlingi, separately, to a conventional PCR method. We determined that a cytochrome b-PCR method was only 3.33% as sensitive and 93.38% as specific as our real-time PCR assay with field-collected samples. We demonstrate that this assay is sensitive, specific and reproducible.

  3. Malaria outside the Amazon region: natural Plasmodium infection in anophelines collected near an indigenous village in the Vale do Rio Branco, Itanhaém, SP, Brazil.

    Science.gov (United States)

    Neves, Amanda; Urbinatti, Paulo Roberto; Malafronte, Rosely dos Santos; Fernandes, Aristides; Paganini, Wanderley da Silva; Natal, Delsio

    2013-01-01

    A few cases of Plasmodium vivax malaria in which anophelines of subgenus Kerteszia were incriminated as vectors have been reported outside the Amazon region, in the Atlantic Forest. This study was carried out near an indigenous Guarani village in the Curucutu reserve, an environmental protection area in the municipality of Itanhaém in the state of São Paulo, Brazil, on November 30, 2009, February 18, 2010, April 29, 2010 and May 26, 2010. Mosquitoes were collected along the route to the Guarani village where the edge of the Branco river floodplain meets the forests on the mountain slopes. Adult forms were collected with CO(2)-baited CDC traps and Shannon traps from twilight to 10:00 P.M. Anopheles cruzii predominated in both traps. The other species collected in the CDC traps were An. pseudomaculipes/maculipes, An. fluminensis and An. mediopunctatus/forattinii/costai. In addition to the latter three species, An. apicimacula/intermedius and An. strodei were also found in the Shannon traps. All but An. cruzii and An. strodei belong to subgenus Anopheles. A total of 506 mosquitoes were assayed by PCR to detect natural infection by Plasmodium species. In the CDC traps, An. fluminensis and An. pseudomaculipes/maculipes were positive for Plasmodium malariae, while in the Shannon traps An. pseudomaculipes/maculipes was positive for Plasmodium vivax and Plasmodium malariae and An. cruzii was positive for P. malariae, resulting in a minimum infection rate of 0.24%. Our findings suggest that An. cruzii may be incriminated in the transmission of malaria between monkeys and humans, as this species was found to be infected by P. malariae. They also highlight the need for an understanding of the role of anophelines from outside subgenus Kerteszia in the transmission of malaria in the Atlantic Forest, as these were also found to be naturally infected by P. vivax and P. malariae.

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

    Science.gov (United States)

    Luz, Christian; Mnyone, Ladslaus L; Russell, Tanya L

    2011-09-01

    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 litter for up to 12 weeks at 26°C and 75%, 86% or >98% relative humidity (RH). Eggs were treated topically with M. anisopliae ICIPE-30 or B. bassiana I93-825 conidia in either water or oil-in-water formulations. Survival of eggs whether treated or not with fungus was similar, and untreated eggs generally did not survive longer than 2 weeks regardless of the substrate or humidity tested. After a minimal 5-day exposure, M. anisopliae at 5 × 10(6) conidia/cm(2) clearly reduced the number of larvae. The efficacy of the fungus increased when it was oil-in-water formulated, and eclosion was completely prevented regardless of the conidial concentration (10(5)-10(7) conidia/cm(2)) after a 10-day exposure in soils at >98% RH. Treatment of eggs with B. bassiana, however, failed to reduce the number of eclosing larvae. This is the first demonstration of the ovicidal activity by M. anisopliae against either A. gambiae s. s. or A. arabiensis and the results underline the potential of this fungus against anopheline mosquitoes.

  5. Relative efficacy of various oils in repelling mosquitoes.

    Science.gov (United States)

    Ansari, M A; Razdan, R K

    1995-09-01

    Field studies were carried out to determine the relative efficacy of repellant action of vegetable, essential and chemical base oils against vector mosquitoes. Results revealed that essential oils viz. Cymbopogan martinii martinii var. Sofia (palmarosa), Cymbopogan citratus (lemon grass) and Cymbopogan nardus (citronella) oils are as effective as chemical base oil namely mylol. These oils provide almost complete protection against Anopheles culicifacies and other anopheline species. Per cent protection against Culex quinquefasciatus ranged between 95-96%. Camphor (C. camphora) oil also showed repellent action and provided 97.6% protection against An. culicifacies and 80.7% against Cx. quinquefasciatus. Vegetable oils namely mustard (B. compestris) and coconut (C. nucisera) showed repellent action, however the efficacy of these oils was not much pronounced against Cx. quinquefasciatus. Results of statistical analysis revealed significant difference between vegetable and essential oils (p mosquitoes. Essential oils were found marginally superior in repellancy than camphor and mylol (p < 0.01) against An. culicifacies and Cx. quinquefasciatus.

  6. Life-table analysis of Anopheles malaria vectors: generational mortality as tool in mosquito vector abundance and control studies

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    Godwin Ray Anugboba Okogun

    2005-06-01

    Full Text Available Background & objectives: Vector control will for sometime remain a primary weapon in the waragainst vector borne diseases. Malaria is of paramount importance in this with its associated highmorbidity and mortality especially in sub-Saharan Africa. This study on generational mortality associatedfactors in Anopheles mosquitoes life-table analysis was designed to investigate the fecundity,levels of mortality and mortality associated factors at the aquatic stages of anopheline malaria vectors.Methods: Mortality associated factors were investigated at the eggs, I and II instar larval, III and IVinstar larval and pupal stages of two anopheline species— Anopheles pseudopunctipennis (Theobaldand An. gambiae life-cycles in screen cages. Adult male and female mosquitoes were membrane filterfedand algae in culture medium formed the bulk of food substances for the larval stage. Environmentaltemperature of culture media, pH and some associated physio-chemical factors were also determined.Results: Results showed significant mortality rates at various aquatic stages. Infertility, cannibalismand environmental factors were the major factors responsible for mortality at the egg, larval and pupalstages respectively.Interpretation & conclusion: The aquatic stages of Anopheles mosquito mortality factor K and themortality factors at the various stages investigated k1, k2, k3 and k4 are discussed. Our recommendationsinclude further studies on the possible genetic modification of predacious An. pseudopunctipennislarvae and/or its modification for the production of sterile/infertile eggs as possible alternativesin the reduction and control of anopheline malaria burden.

  7. A survey of adult anophelines in French Guiana: enhanced descriptions of species distribution and biting responses.

    Science.gov (United States)

    Dusfour, Isabelle; Carinci, Romuald; Issaly, Jean; Gaborit, Pascal; Girod, Romain

    2013-12-01

    In French Guiana, Anopheles darlingi is considered the main malaria vector. However, several reports have hypothesized the implication of other anopheline species in malaria transmission for the territory. Data on the ecology of these other potential vectors is rare or even unexplored in French Guiana. The aim of this study was to describe the biting habits of several anopheline species in multiple localities in French Guiana. Six sampling sites yielded 1,083 anopheline adults. Results indicated the presence of An. darlingi in all study locations and it was the only species to be collected inside villages. Other anophelines collected included An. aquasalis, An. braziliensis, An. intermedius, An. mediopunctatus, An. nuneztovari, An. oswaldoi, and An. triannulatus, all of which were associated with open areas and forests. The environment and time, at which biting behavior was recorded, varied for each species. It was noted that An. oswaldoi showed a daytime rhythm in open areas. This study is the first to report on the biting habits of a range of anophelines in French Guiana that may play a role in malaria transmission. This information is vital to fully describe the risk of malaria transmission and thereby design appropriate vector control measures and malaria prevention programs.

  8. Development of Metarhizium anisopliae and Beauveria bassiana formulations for control of malaria mosquito larvae

    Directory of Open Access Journals (Sweden)

    Takken Willem

    2011-02-01

    a suitable carrier are a promising tool for control of larval populations of malaria mosquitoes. Additional studies are required to identify the best delivery method (where, when and how to make use of the entomopathogenic potential of these fungi against anopheline larvae.

  9. Caspar controls resistance to Plasmodium falciparum in diverse anopheline species.

    OpenAIRE

    Garver, Lindsey S.; Yuemei Dong; George Dimopoulos

    2009-01-01

    Immune responses mounted by the malaria vector Anopheles gambiae are largely regulated by the Toll and Imd (immune deficiency) pathways via the NF-kappaB transcription factors Rel1 and Rel2, which are controlled by the negative regulators Cactus and Caspar, respectively. Rel1- and Rel2-dependent transcription in A. gambiae has been shown to be particularly critical to the mosquito's ability to manage infection with the rodent malaria parasite Plasmodium berghei. Using RNA interference to depl...

  10. Benito Arias Montano y Francisco Arceo: la redacción del De recta curandorum vulnerum ratione

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    Montero Cartelle, Enrique

    2012-12-01

    Full Text Available When comparing language and literary resources in the treatise De recta curandorum vulnerum ratione, written by the 16th practical surgeon Francisco Arceo, to the prologue added by his guest, friend and compatriot, the humanist Arias Montano, it bears so remarkable resemblence that proves the intervention of the latter by arranging the text or even writing it in his own latin style. Furthermore, Arias Montano made the book be annotated and printed in Amberes by Cristobal Plantino’s printing press, one of his dearest friends.La comparación sistemática de la lengua y de los recursos literarios del tratado De recta curandorum vulnerum ratione, obra del cirujano práctico del siglo XVI Francisco Arceo, con la lengua del Prólogo que le puso su huésped, amigo y paisano, el humanista Arias Montano, muestra semejanzas tan significativas que prueban la intervención de este último arreglando el texto o redactándolo con el latín que le caracteriza. Arias Montano, además, hizo anotar la obra y se la publicó en Amberes en la imprenta de su buen amigo Cristóbal Plantino.

  11. Flying vaccinator; a transgenic mosquito delivers a Leishmania vaccine via blood feeding.

    Science.gov (United States)

    Yamamoto, D S; Nagumo, H; Yoshida, S

    2010-06-01

    'Flying vaccinator' is the concept of using genetically engineered hematophagous insects to deliver vaccines. Here we show the generation of a transgenic anopheline mosquito that expresses the Leishmania vaccine candidate, SP15, fused to monomeric red fluorescent protein (mDsRed) in its salivary glands. Importantly, mice bitten repeatedly by the transgenic mosquitoes raised anti-SP15 antibodies, indicating delivery of SP15 via blood feeding with its immunogenicity intact. Thus, this technology makes possible the generation of transgenic mosquitoes that match the original concept of a 'flying vaccinator'. However, medical safety issues and concerns about informed consent mitigate the use of the 'flying vaccinator' as a method to deliver vaccines. We propose that this expression system could be applied to elucidate saliva-malaria sporozoite interactions.

  12. Plasmodium knowlesi in humans, macaques and mosquitoes in peninsular Malaysia

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    NorParina Ismail

    2008-08-01

    Full Text Available Abstract Background Since a large focus of human infection with Plasmodium knowlesi, a simian malaria parasite naturally found in long-tailed and pig tailed macaques, was reported in Sarawak, Malaysian Borneo, it was pertinent to study the situation in peninsular Malaysia. A study was thus initiated to screen human cases of Plasmodium malariae using molecular techniques, to determine the presence of P. knowlesi in non- human primates and to elucidate its vectors. Methods Nested polymerase chain reaction (PCR was used to identify all Plasmodium species present in the human blood samples sent to the Parasitology laboratory of Institute for Medical Research. At the same time, non-human primates were also screened for malaria parasites and nested PCR was carried out to determine the presence of P. knowlesi. Mosquitoes were collected from Pahang by human landing collection and monkey-baited-traps situated on three different levels. All mosquitoes were identified and salivary glands and midguts of anopheline mosquitoes were dissected to determine the presence of malaria parasites and nested PCR was carried out on positive glands. Sequencing of the csp genes were carried on P. knowlesi samples from humans, monkeys and mosquitoes, positive by PCR. Results and Discussion Plasmodium knowlesi was detected in 77 (69.37% of the 111 human samples, 10 (6.90% of the 145 monkey blood and in 2 (1.7% Anopheles cracens. Sequence of the csp gene clustered with other P. knowlesi isolates. Conclusion Human infection with Plasmodium knowlesi is occurring in most states of peninsular Malaysia. An. cracens is the main vector. Economic exploitation of the forest is perhaps bringing monkeys, mosquitoes and humans into increased contact. A single bite from a mosquito infected with P. knowlesi is sufficient to introduce the parasite to humans. Thus, this zoonotic transmission has to be considered in the future planning of malaria control.

  13. Status of carbohydrate, protein and lipid profile in the mosquito larvae treated with certain phytoextracts

    Institute of Scientific and Technical Information of China (English)

    Preeti Sharma; Lalit Mohan; Kamal Kumar Dua; Chand Narayan Srivastava

    2011-01-01

    Objective:To investigate the impact of the most potent petroleum ether extract ofArtemisia annua (A. annua) andAzadirachta indica (Az. indica) on total carbohydrate, lipid and protein level ofAnopheles stephensi andCulex quinquefasciatuslarvae.Methods: Mosquito larvae were exposed to the extracts selected as per standardWHO procedure. Carbohydrate (glucose), total lipid and protein were estimated by the methods as Nelson, Bragdon and Lowry described, respectively.Results: The glucose levels were increased to27.87% and46.8%, respectively in anopheline larval tissues after treatment with petroleum ether extract ofA. annua and methanolic extract ofAz. indica. In culicine larvae, glucose levels were reduced to58.96% and24.65%, respectively. After treatment withA. annua extract, lipid contents in anopheline and culicine larvae decreased by28.57% and25.0%, respectively and increased by14.29% and50.00% in theAnopheles andCulex larvae, respectively after treatment with methanolic extract ofAz. indica. Total protein levels were reduced to63.13% and92.62% in anopheline and to32.39% and 48.12% in culicine larvae after treatment withA. annua andAz. Indica extracts, respectively. Conclusions: Two extracts produce significant alterations in the biochemical profiles of anopheline and culicine larvae. Further, the impacting factors of extracts on carbohydrate, lipid and protein contents of larvae are species and specific extraction. It indicates the disturbed metabolic activity of the larvae.

  14. Comparison of the Performances of Five Primer Sets for the Detection and Quantification of Plasmodium in Anopheline Vectors by Real-Time PCR.

    Directory of Open Access Journals (Sweden)

    V Chaumeau

    Full Text Available Quantitative real-time polymerase chain reaction (qrtPCR has made a significant improvement for the detection of Plasmodium in anopheline vectors. A wide variety of primers has been used in different assays, mostly adapted from molecular diagnosis of malaria in human. However, such an adaptation can impact the sensitivity of the PCR. Therefore we compared the sensitivity of five primer sets with different molecular targets on blood stages, sporozoites and oocysts standards of Plasmodium falciparum (Pf and P. vivax (Pv. Dilution series of standard DNA were used to discriminate between methods at low concentrations of parasite and to generate standard curves suitable for the absolute quantification of Plasmodium sporozoites. Our results showed that the best primers to detect blood stages were not necessarily the best ones to detect sporozoites. Absolute detection threshold of our qrtPCR assay varied between 3.6 and 360 Pv sporozoites and between 6 and 600 Pf sporozoites per mosquito according to the primer set used in the reaction mix. In this paper, we discuss the general performance of each primer set and highlight the need to use efficient detection methods for transmission studies.

  15. Comparison of the Performances of Five Primer Sets for the Detection and Quantification of Plasmodium in Anopheline Vectors by Real-Time PCR.

    Science.gov (United States)

    Chaumeau, V; Andolina, C; Fustec, B; Tuikue Ndam, N; Brengues, C; Herder, S; Cerqueira, D; Chareonviriyaphap, T; Nosten, F; Corbel, V

    2016-01-01

    Quantitative real-time polymerase chain reaction (qrtPCR) has made a significant improvement for the detection of Plasmodium in anopheline vectors. A wide variety of primers has been used in different assays, mostly adapted from molecular diagnosis of malaria in human. However, such an adaptation can impact the sensitivity of the PCR. Therefore we compared the sensitivity of five primer sets with different molecular targets on blood stages, sporozoites and oocysts standards of Plasmodium falciparum (Pf) and P. vivax (Pv). Dilution series of standard DNA were used to discriminate between methods at low concentrations of parasite and to generate standard curves suitable for the absolute quantification of Plasmodium sporozoites. Our results showed that the best primers to detect blood stages were not necessarily the best ones to detect sporozoites. Absolute detection threshold of our qrtPCR assay varied between 3.6 and 360 Pv sporozoites and between 6 and 600 Pf sporozoites per mosquito according to the primer set used in the reaction mix. In this paper, we discuss the general performance of each primer set and highlight the need to use efficient detection methods for transmission studies.

  16. Mosquito, egg raft (image)

    Science.gov (United States)

    Mosquitoes of the Culex species lay their eggs in the form of egg rafts that float in ... feed on micro-organisms before developing into flying mosquitoes. (Image courtesy of the Centers for Disease Control ...

  17. Mosquito, adult (image)

    Science.gov (United States)

    This illustration shows an adult southern house mosquito. This mosquito feeds on blood and is the carrier of many diseases, such as encephalitis, West Nile, dengue fever, yellow fever, and others. ( ...

  18. Controlling Mosquitoes Outside

    Centers for Disease Control (CDC) Podcasts

    2016-08-09

    Mosquitoes can carry viruses, like West Nile, Zika, dengue, and chikungunya. In this podcast, Mr. Hubbard will teach you and his neighbor, Laura, ways to help reduce the number of mosquitoes outside your home. Tips include eliminating areas of standing water where mosquitoes lay eggs and using larvicides to kill young mosquitoes.  Created: 8/9/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/9/2016.

  19. MAN, MOSQUITOES AND MICROBES.

    Science.gov (United States)

    SCHOONOVER, ROBERT A.

    THE CONTROL OF MOSQUITOES IS A MATTER OF INCREASING CONCERN IN THE STATE OF FLORIDA. A BRIEF DESCRIPTION OF THE LIFE CYCLE, VARIOUS SPECIES, CONTROL, AND DESCRIPTION OF DISEASES TRANSMITTED BY THE MOSQUITO WAS PRESENTED. THE ARTICLE CONCLUDED THAT MOSQUITO CONTROL IS NOT ONLY A HEALTH PROBLEM, BUT ALSO A MATTER OF IMPROVED ECONOMICS IN RELATION TO…

  20. [Progress on transgenic mosquitoes].

    Science.gov (United States)

    Yang, Pin

    2011-04-30

    The genetically modified mosquitoes have been developed aiming to control mosquito-borne diseases by either reducing population sizes or replacing existing populations with vectors unable to transmit the disease. introduces some progress on the generation of transgenic mosquitoes and their fitness in wild population. This paper

  1. Thorsellia anophelis is the dominant bacterium in a Kenyan population of adult Anopheles gambiae mosquitoes.

    Science.gov (United States)

    Briones, Aurelio M; Shililu, Josephat; Githure, John; Novak, Robert; Raskin, Lutgarde

    2008-01-01

    Anopheles gambiae mosquitoes are not known to harbor endosymbiotic bacteria. Here we show, using nucleic acid-based methods, that 16S rRNA gene sequences specific to a recently described mosquito midgut bacterium, Thorsellia anophelis, is predominant in the midgut of adult An. gambiae s.l. mosquitoes captured in residences in central Kenya, and also occurs in the aquatic rice paddy environment nearby. PCR consistently detected T. anophelis in the surface microlayer of rice paddies, which is also consistent with the surface-feeding behavior of A. gambiae s.l. larvae. Phylogenetic analysis of cloned environmental 16S rRNA genes identified four major Thorsellia lineages, which are closely affiliated to an insect endosymbiont of the genus Arsenophonus. Physiological characterizations support the hypothesis that T. anophelis is well adapted to the female anopheline midgut by utilizing blood and tolerating the alkaline conditions in this environment. The results suggest that aquatically derived bacteria such as T. anophelis can persist through mosquito metamorphosis and become well-established in the adult mosquito midgut.

  2. IGF-II receptors in luminal and basolateral membranes isolated from pars convoluta and pars recta of rabbit proximal tubule

    DEFF Research Database (Denmark)

    Jacobsen, Christian; Jessen, H; Flyvbjerg, A

    1995-01-01

    The binding of 125I-labeled insulin-like growth factor-II (125I-IGF-II) to luminal and basolateral membrane vesicles isolated from pars convoluta and the straight part (pars recta) of rabbit proximal tubule was investigated. Analyses of the binding data by use of the general stoichiometric binding...... equation revealed, that in all preparations IGF-II was bound to one high-affinity binding site and other sites with lower affinities. The specificity of the high-affinity 125I-IGF-II binding to the membrane vesicles assessed by displacement by unlabeled IGF-II, IGF-I and insulin showed that IGF-I displaced...... 125I-IGF-II in the range 22.5-47.9 nM (IC50) whereas insulin did not effect 125I-IGF-II binding at all. beta-Galactosidase inhibited the 125I-IGF-II binding with half-maximal inhibition of 20-30 nM beta-galactosidase. D-Mannose 6-phosphate increased the binding of 125I-IGF-II and reversed...

  3. Pyrethroid resistance in mosquitoes

    Institute of Scientific and Technical Information of China (English)

    NANNAN LIU; QIANG XU; FANG ZHU; LEE ZHANG

    2006-01-01

    Repeated blood feedings throughout their life span have made mosquitoes ideal transmitters of a wide variety of disease agents. Vector control is a very important part of the current global strategy for the control of mosquito-associated diseases and insecticide application is the most important component in this effort. Pyrethroids, which account for 25% of the world insecticide market, are currently the most widely used insecticides for the indoor control of mosquitoes and are the only chemical recommended for the treatment of mosquito nets, the main tool for preventing malaria in Africa. However, mosquito-borne diseases are now resurgent, largely because of insecticide resistance that has developed in mosquito vectors and the anti-parasite drug resistance of parasites. This paper reviews our current knowledge of the molecular mechanisms governing metabolic detoxification and the development of target site insensitivity that leads to pyrethroid resistance in mosquitoes.

  4. Ecology of Anopheline (Diptera, Culicidae, malaria vectors around the Serra da Mesa Reservoir, State of Goiás, Brazil: 1 - Frequency and climatic factors

    Directory of Open Access Journals (Sweden)

    Anthony Érico Guimarães

    Full Text Available The ecology of anopheline species (Diptera, Culicidae was studied in the vicinity of the Serra da Mesa Reservoir, State of Goiás, Brazil. Climatic factors and frequency of anopheline populations were analyzed. Bimonthly human-bait and Shannon trap captures were conducted for 36 consecutive months (January 1997 through December 1999. A total of 5,205 adult anophelines belonging to five species were collected. Anopheles darlingi was the most frequently collected anopheline (61.4%, followed by An. albitarsis s.l. (35.4%, An. triannulatus. (2.5%, An. oswaldoi (0.4%, and An. evansae (0.2%. The water level and vegetation along the banks of the reservoir were crucial to the frequency of the various anopheline species. Climatic factors had a secondary influence. The reservoir's water-level stability, increased frequency of An. darlingi, and the arrival of gold prospectors were responsible for the increase in malaria cases.

  5. Artificial Diets for Mosquitoes

    Directory of Open Access Journals (Sweden)

    Kristina K. Gonzales

    2016-12-01

    Full Text Available Mosquito-borne diseases are responsible for more than a million human deaths every year. Modern mosquito control strategies such as sterile insect technique (SIT, release of insects carrying a dominant lethal (RIDL, population replacement strategies (PR, and Wolbachia-based strategies require the rearing of large numbers of mosquitoes in culture for continuous release over an extended period of time. Anautogenous mosquitoes require essential nutrients for egg production, which they obtain through the acquisition and digestion of a protein-rich blood meal. Therefore, mosquito mass production in laboratories and other facilities relies on vertebrate blood from live animal hosts. However, vertebrate blood is expensive to acquire and hard to store for longer times especially under field conditions. This review discusses older and recent studies that were aimed at the development of artificial diets for mosquitoes in order to replace vertebrate blood.

  6. Controlling Mosquitoes Indoors

    Centers for Disease Control (CDC) Podcasts

    2016-08-23

    Mosquitoes can carry viruses, like West Nile and Zika. In this podcast, Mr. Hubbard teaches his neighbors, the Smith family, ways to help reduce the number of mosquitoes inside their home.  Created: 8/23/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/23/2016.

  7. Electronic technology of mosquitoes control and repelling%电子驱灭蚊蝇技术的研究

    Institute of Scientific and Technical Information of China (English)

    王钧; 陈明媛

    2013-01-01

      蚊蝇等害虫对人类的健康构成了危害。蚊香、灭蚊剂等传统的驱灭蚊子方法不仅使它们产生了抗药性,而且会造成环境污染[1]。本文通过分析蚊子的生活特性,利用现代电子技术、仿生学和物理技术等非化学方法实现了绿色驱灭蚊子。经实验研究,该方法比传统的方法更加环保、高效。%Pests such as mosquitoes are harm to human's health. Driving and killing mosquitoes by mosquito-repellent incense and anopheline in the traditional ways not only cause their developed resistance, and will cause environmental pollution [1]. Through analysis of the characteristics of mosquitoes, the modern electronic technology, bionics and physical technology, not chemical methods, have been realized controlling and repelling mosquitoes. After experimental research, the idea is better than the traditional method, with more environmental protection, high efficiency.

  8. Mosquito immunity against arboviruses.

    Science.gov (United States)

    Sim, Shuzhen; Jupatanakul, Natapong; Dimopoulos, George

    2014-11-19

    Arthropod-borne viruses (arboviruses) pose a significant threat to global health, causing human disease with increasing geographic range and severity. The recent availability of the genome sequences of medically important mosquito species has kick-started investigations into the molecular basis of how mosquito vectors control arbovirus infection. Here, we discuss recent findings concerning the role of the mosquito immune system in antiviral defense, interactions between arboviruses and fundamental cellular processes such as apoptosis and autophagy, and arboviral suppression of mosquito defense mechanisms. This knowledge provides insights into co-evolutionary processes between vector and virus and also lays the groundwork for the development of novel arbovirus control strategies that target the mosquito vector.

  9. LARVICICAL ACTIVITY OF BACILLUS THURINGIENSIS H-14 (TEKNAR ON MOSQUITO LARVAE IN RICEFIELDS, SOUTHERN IRAN

    Directory of Open Access Journals (Sweden)

    M.Motabar

    1986-12-01

    Full Text Available An investigation was conducted to study the larvicidal activity of Teknar (San-402-I-Bacillus thuringiensis, serotype H-14, Sandoz, 600 ITU/mg on mosquitolarvaein Kazeroun, Fars Province, southern Iran. Five experimental plots were selected randomly in a rice field and three concentrations of Teknar: .0003, .0006 and .0012 cc/1 was used. Maximum larval mortality usually occurred during the first 24 hours of exposure. Culicinae larvae were more susceptible than the anophelines. Also, the first and second instars showed greater mortality than the third and fourth instars. The percent larval vortality were 71.8 to 81.5 in anophelines and 82.1 to 100 in culicinae at.0003 cc/1, 89.4 to 100 in anophelinae and 97.2 to 100 in culicinae at.0006 cc/1and 98.4 to 98.6 in anophelinae and 100 in culicinae at.0012 cc/1 concentrations respectively. No mortality was detected in the control plots. It was concluded that.0006 and .0003 cc/1 were the concentrations of choice for the proper mosquito larval control in the area.

  10. The mosquitoes (Diptera: Culidae of Seychelles: taxonomy, ecology, vectorial importance, and identification keys

    Directory of Open Access Journals (Sweden)

    Le Goff Gilbert

    2012-09-01

    browni. Ur. nepenthes and Ur. pandani and one subspecies (Ae. vigilax vansomerenae are considered as endemic. Two illustrated identification keys, one for adult females and the other for larval stages, are presented. Conclusions The knowledge of the culicidian fauna in the Seychelles has been notably updated. The number of mosquito species is relatively large with regards to land surface and distances to continental Africa, although the anophelines are totally lacking. The complex natural history of mosquitoes in the Seychelles provides examples of both vicariance- and dispersal-mediated divergences. They present superb examples for theoretical and applied island biology.

  11. Mosquitoes of Middle America.

    Science.gov (United States)

    1976-09-30

    FL; (I S) Museu de Zoologia da (Jniversidade de Sao Paulo , Instituto Adolfo Lu tz in Sao Paulo and Instituto de Microbiologia , Un iversidade...Herbert C., Inst ituto de Microbiologia , Universidade Federal do Rio de Janeiro , Brazil. — Facilities for topotypic survey of mosquitoes in Rio de...976 17 Garcia , M iguel, Departamento de Entomologia Sanitaria , Instituto de Microbiologia , Buenos Aires, Argentina . — Mosquitoes from Argentina

  12. 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.

  13. Evaluation of biological control agents for mosquitoes control in artificial breeding places

    Institute of Scientific and Technical Information of China (English)

    Salim Abadi Yaser; Vatandoost Hassan; Rassi Yavar; Abai Mohammad Reza; Sanei Dehkordi Ali Reza; Paksa Azim

    2010-01-01

    Objective:To evaluate the entomological impact of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on mosquitoes control in artificial breeding places.Methods:A Latin square design with 4 replicates was performed in order to evaluate the efficacy of chlorpyrifos-methyl,Bacillus thuringiensis, andGambusia affinis on larva. The larvicide was applied at the dosage of 100 mg a.h/ha,Bacillus thuringiensis at the recommended dosage and 10 fishes per m2 were applied at 1í1 m2 artificial breeding sites. The larval densities for both anopheline and culicine were counted according to larvae /10 dippers prior and 24 h after application.Results:All three control agents are effective for mosquito density reduction, and the difference between the three agents and the control is significant (P<0.05). There is also significant difference among chlorpyrifos-methyl,Bacillus thuringiensis andGambusia affinis.Bacillus thuringiensisexhibited more reduction on mosquito larval density than fish and larvicide (P<0.05).Conclusions:Bacillus thuringiensis in comparison with two other agents is the appropriate method for larviciding in the breeding places. Although long term assessing for biological activities as well as monitoring and mapping of resistance is required.

  14. Investigation on Anopheline species in Chayu County, Linzhi Prefecture of Tibet Autonomous Region%西藏林芝地区察隅县按蚊种群调查

    Institute of Scientific and Technical Information of China (English)

    王洪举; 胡松林; 李松凌; 顾政诚; 陈建设; 朱国鼎; 黄芳

    2012-01-01

    目的 确定西藏林芝地区察隅县主要按蚊蚊种.方法 2010年7-8月在察隅县选择4个自然村,采用通宵/半通宵室内、外人饵帐诱捕法和通宵诱蚊灯诱捕法捕蚊,对捕获的按蚊进行形态学鉴定.结果 共捕获按蚊2 991只,其中带足按蚊2 284只(占76.36%),多斑按蚊种团667只(占22.30%),其他按蚊40只(占1.34%);带足按蚊室内、外半通宵平均密度分别为56.2只/夜和4只/夜,多斑按蚊种团室内、外半通宵平均密度分别为17.8只/夜和17.9只/夜;带足按蚊室内、外全通宵室内叮人率分别为28.1只/(人·夜)和2只/(人·夜),多斑按蚊种团全通宵室内、外叮人率均为8.9只/(人·夜).结论 带足按蚊和多斑按蚊为察隅县优势蚊种,是可能的疟疾传播媒介.%Objective To investigate Anopheline species in Chayu County of Linzhi Prefecture, Tibet Methods Four natural villages in Chayu County were selected in this study in 2010. The methods of overnighl/semi-overaight trapping indoor and outdoor human-bait, and overnight trapping with light traps were used, and all the Anopheline mosquitoes were confirmed by morphological characteristics. Results Totally 2 991 Anopheline mosquitoes were captured, with 76.36% (2 284/2 291) of An, peditae-niatus, 22.30% (667/2 291) of An. maculates group. The average densities of An. peditaeniatus by semi-overnight trapping were 56.2/per person indoor and 4/per person outdoor respectively, and the average densities of An. maculatus group by semi-overnight trapping were 17.8/per person indoor and 17.9/per person outdoor respectively. The man-biting rates of An. peditaeniatus by overnight trapping were 28.I/per person indoor and 2/per person outdoor respectively, and were both 8.9/per person to An. maculatus group. Conclusion An. peditaeniatus and An. maculatus group are the possible transmission vectors of malaria in Chayu County.

  15. Anopheline Diversity: Morphological and Molecular Variation of An. subpictus in Rural and Urban Areas of West Bengal

    Directory of Open Access Journals (Sweden)

    Satarupa Paul

    2013-04-01

    Full Text Available A systematic survey (March 2012- Feb 2013of Anopheline population in rural(Mogra and urban(Dumdum areas of West Bengal has been conducted to know the present population load of Anopheles subpictus. A reliminary attempt has been made to assess the potential morphological (wing as well as molecular variation of Anopheles subpictus by using ITS-2 sequence primer. A considerable sequence variation is observed between the rural and urban population of West Bengal.

  16. 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.

    Science.gov (United States)

    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.

  17. High mosquito burden and malaria transmission in a district of the city of Douala, Cameroon

    Directory of Open Access Journals (Sweden)

    Antonio-Nkondjio Christophe

    2012-10-01

    Full Text Available Abstract Background Rapid demographic growth in Douala city, Cameroon, has resulted in profound ecological and environmental changes. Although demographic changes can affect anopheline mosquito breeding sites, there is a lack of understanding about the epidemiological impact that such changes might have on vector ecology and malaria transmission. Methods A 12-month entomological study was conducted in a highly populated district of Douala called Ndogpassi. Adult mosquitoes were collected using two methods: 1 human landing catches (HLC; and 2 Centers for Disease Control and Prevention (CDC light traps; these methods were used twice monthly from January to December 2011. Mosquito genus and species were identified with morphological and molecular diagnostic tools. The sampling efficiency of the CDC light trap and HLC were compared. Anopheles gambiae infection with Plasmodium falciparum was detected using ELISA. Susceptibility to DDT, permethrin, and deltamethrin insecticides were also determined. Results A total of 6923 mosquitoes were collected by HLC (5198 and CDC light traps (1725. There was no equivalence in the sampling efficiency between light traps and human landing catches (P > 0.01. With 51% of the total, Culex was the most common, followed by Anopheles (26.14%, Mansonia (22.7% and Aedes (0.1%. An. gambiae ss (M form comprised ~98% of the total anophelines collected. An. gambiae had a biting rate of 0.25 to 49.25 bites per human per night, and was the only species found to be infected with P. falciparum. A P. falciparum infection rate of 0.5% was calculated (based on enzyme-linked immunosorbent assays using the circumsporozoite surface protein. The entomological inoculation rate was estimated at 31 infective bites per annum. Insecticide susceptibility tests on An. gambiae females revealed a mortality rate of 33%, 76% and 98% for DDT, permethrin and deltamethrin, respectively. The West African kdr allele (L1014F was detected in 38 of

  18. Development of Metarhizium anisopliae and Beauveria bassiana formulations for control of malaria mosquito larvae

    NARCIS (Netherlands)

    Bukhari, S.T.; Takken, W.; Koenraadt, C.J.M.

    2011-01-01

    Background The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana have demonstrated effectiveness against anopheline larvae in the laboratory. However, utilising these fungi for the control of anopheline larvae under field conditions, relies on development of effective means of app

  19. Mosquitoes, models, and dengue.

    Science.gov (United States)

    Lifson, A R

    1996-05-04

    In the last 10 years dengue has spread markedly through Latin America and the Caribbean (Dominican Republic, Jamaica, Barbados, Mexico, Guatemala, El Salvador, Honduras, Nicaragua, Costa Rica, Panama, Ecuador, Colombia, Venezuela, and Brazil). The mosquito Aedes aegypti has taken advantage of increased urbanization and crowding to transmit the dengue virus. The mosquito infests tires, cans, and water jars near dwellings. The female mosquito practices multiple, interrupted feeding. Thus, mosquito infesting and feeding practices facilitate dengue transmission in crowded conditions. Factors contributing to the spread of dengue include numbers of infected and susceptible human hosts, strain of dengue virus, size of mosquito population, feeding habits, time from infection to ability to transmit virus for both vector and host, likelihood of virus transmission from human to mosquito to human, and temperature (which affects vector distribution, size, feeding habits, and extrinsic incubation period). Public health models may use simulation models to help them plan or evaluate the potential impact of different intervention strategies and/or of environmental changes (e.g., global warming). Other factors contributing to the dengue epidemic are international travel, urbanization, population growth, crowding, poverty, a weakened public health infrastructure, and limited support for sustained disease control programs. Molecular epidemiology by nucleic acid sequence analysis is another sophisticated technique used to study infectious diseases. It showed that dengue type 3 isolated from Panama and Nicaragua in 1994 was identical to that responsible for the major dengue hemorrhagic fever epidemics in Sri Lanka and India in the 1980s. Public health officials must remember three priorities relevant to dengue and other emerging infections: the need to strengthen surveillance efforts, dedicated and sustained involvement in prevention and control needs at the local level, and a strong

  20. Flavivirus-Mosquito Interactions

    Directory of Open Access Journals (Sweden)

    Yan-Jang S. Huang

    2014-11-01

    Full Text Available The Flavivirus genus is in the family Flaviviridae and is comprised of more than 70 viruses. These viruses have a broad geographic range, circulating on every continent except Antarctica. Mosquito-borne flaviviruses, such as yellow fever virus, dengue virus serotypes 1–4, Japanese encephalitis virus, and West Nile virus are responsible for significant human morbidity and mortality in affected regions. This review focuses on what is known about flavivirus-mosquito interactions and presents key data collected from the field and laboratory-based molecular and ultrastructural evaluations.

  1. Population dynamics and spatial structure of human-biting mosquitoes, inside and outside of houses, in the Chockwe irrigation scheme, southern Mozambique

    Directory of Open Access Journals (Sweden)

    J. Derek Charlwood

    2013-05-01

    Full Text Available Focal control of malaria vectors, a potentially cost-effective alternative to conventional control, requires a spatio-temporal understanding of the mosquitoes. Trapping of African malaria vectors has generally been limited to inside houses making distribution estimates dependent on the location of dwellings. The development of tent-traps to sample outdoor biting mosquitoes has enabled more independent estimates. Here we describe both temporal and spatial variation in mosquito movements in an irrigation project village in southern Mozambique. Six hundred and ninety-three tent-trap collections (525 of which were paired with light-trap collections, 552 exit collections and 391 collections of mosquitoes resting inside houses were undertaken from March 2005 to April 2006. Fifteen species of mosquito were collected (five exclusively as larvae. Mansonia africana was the most common finding, numbers being greatest away from the village. Only Anopheles funestus, An. tenebrosus and Culex quinquefasciatus were collected in greater numbers in light-traps compared to tent-traps. Among the common mosquitoes, correlations in numbers of mosquito collected in paired tent and in light-traps were significant for all but An. tenebrosus. Inverse distance weighting was used to produce raster density maps of the most common mosquitoes. All species, with minor variations, in both hot and cool seasons, were collected in greatest numbers close to the edges of the village where water suitable for larval development was available. All exophilic anophelines species tested negative for sporozoites. It is suggested that focal control of larvae, applied by the villagers themselves, could be a suitable alternative to conventional control in this and similar villages.

  2. Population dynamics and spatial structure of human-biting mosquitoes, inside and outside of houses, in the Chockwe irrigation scheme, southern Mozambique.

    Science.gov (United States)

    Charlwood, J Derek; Macia, Gracieta A; Manhaca, Maria; Sousa, Bruno; Cuamba, Nelson; Bragança, Mauro

    2013-05-01

    Focal control of malaria vectors, a potentially cost-effective alternative to conventional control, requires a spatio-temporal understanding of the mosquitoes. Trapping of African malaria vectors has generally been limited to inside houses making distribution estimates dependent on the location of dwellings. The development of tent-traps to sample outdoor biting mosquitoes has enabled more independent estimates. Here we describe both temporal and spatial variation in mosquito movements in an irrigation project village in southern Mozambique. Six hundred and ninety-three tent-trap collections (525 of which were paired with light-trap collections), 552 exit collections and 391 collections of mosquitoes resting inside houses were undertaken from March 2005 to April 2006. Fifteen species of mosquito were collected (five exclusively as larvae). Mansonia africana was the most common finding, numbers being greatest away from the village. Only Anopheles funestus, An. tenebrosus and Culex quinquefasciatus were collected in greater numbers in light-traps compared to tent-traps. Among the common mosquitoes, correlations in numbers of mosquito collected in paired tent and in light-traps were significant for all but An. tenebrosus. Inverse distance weighting was used to produce raster density maps of the most common mosquitoes. All species, with minor variations, in both hot and cool seasons, were collected in greatest numbers close to the edges of the village where water suitable for larval development was available. All exophilic anophelines species tested negative for sporozoites. It is suggested that focal control of larvae, applied by the villagers themselves, could be a suitable alternative to conventional control in this and similar villages.

  3. Loss of protection with insecticide-treated nets against pyrethroid-resistant Culex quinquefasciatus mosquitoes once nets become holed: an experimental hut study

    Directory of Open Access Journals (Sweden)

    Irish SR

    2008-06-01

    Full Text Available Abstract Background An important advantage of pyrethroid-treated nets over untreated nets is that once nets become worn or holed a pyrethroid treatment will normally restore protection. The capacity of pyrethroids to kill or irritate any mosquito that comes into contact with the net and prevent penetration of holes or feeding through the sides are the main reasons why treated nets continue to provide protection despite their condition deteriorating over time. Pyrethroid resistance is a growing problem among Anopheline and Culicine mosquitoes in many parts of Africa. When mosquitoes become resistant the capacity of treated nets to provide protection might be diminished, particularly when holed. An experimental hut trial against pyrethroid-resistant Culex quinquefasciatus was therefore undertaken in southern Benin using a series of intact and holed nets, both untreated and treated, to assess any loss of protection as nets deteriorate with use and time. Results There was loss of protection when untreated nets became holed; the proportion of mosquitoes blood feeding increased from 36.2% when nets were intact to between 59.7% and 68.5% when nets were holed to differing extents. The proportion of mosquitoes blood feeding when treated nets were intact was 29.4% which increased to 43.6–57.4% when nets were holed. The greater the number of holes the greater the loss of protection regardless of whether nets were untreated or treated. Mosquito mortality in huts with untreated nets was 12.9–13.6%; treatment induced mortality was less than 12%. The exiting rate of mosquitoes into the verandas was higher in huts with intact nets. Conclusion As nets deteriorate with use and become increasingly holed the capacity of pyrethroid treatments to restore protection is greatly diminished against resistant Culex quinquefasciatus mosquitoes.

  4. Screening mosquito house entry points as a potential method for integrated control of endophagic filariasis, arbovirus and malaria vectors.

    Directory of Open Access Journals (Sweden)

    Sheila B Ogoma

    Full Text Available BACKGROUND: Partial mosquito-proofing of houses with screens and ceilings has the potential to reduce indoor densities of malaria mosquitoes. We wish to measure whether it will also reduce indoor densities of vectors of neglected tropical diseases. METHODOLOGY: The main house entry points preferred by anopheline and culicine vectors were determined through controlled experiments using specially designed experimental huts and village houses in Lupiro village, southern Tanzania. The benefit of screening different entry points (eaves, windows and doors using PVC-coated fibre glass netting material in terms of reduced indoor densities of mosquitoes was evaluated compared to the control. FINDINGS: 23,027 mosquitoes were caught with CDC light traps; 77.9% (17,929 were Anopheles gambiae sensu lato, of which 66.2% were An. arabiensis and 33.8% An. gambiae sensu stricto. The remainder comprised 0.2% (50 An. funestus, 10.2% (2359 Culex spp. and 11.6% (2664 Mansonia spp. Screening eaves reduced densities of Anopheles gambiae s. l. (Relative ratio (RR = 0.91; 95% CI = 0.84, 0.98; P = 0.01; Mansonia africana (RR = 0.43; 95% CI = 0.26, 0.76; P<0.001 and Mansonia uniformis (RR = 0.37; 95% CI = 0.25, 0.56; P<0.001 but not Culex quinquefasciatus, Cx. univittatus or Cx. theileri. Numbers of these species were reduced by screening windows and doors but this was not significant. SIGNIFICANCE: This study confirms that across Africa, screening eaves protects households against important mosquito vectors of filariasis, Rift Valley Fever and O'Nyong nyong as well as malaria. While full house screening is required to exclude Culex species mosquitoes, screening of eaves alone or fitting ceilings has considerable potential for integrated control of other vectors of filariasis, arbovirus and malaria.

  5. Mosquito Bites are Bad!

    Centers for Disease Control (CDC) Podcasts

    2016-08-11

    In this podcast for kids, the Kidtastics talk about the dangers of mosquito bites and how to prevent getting them.  Created: 8/11/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/11/2016.

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

    Directory of Open Access Journals (Sweden)

    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.

  7. Multiple insecticide resistance mechanisms involving metabolic changes and insensitive target sites selected in anopheline vectors of malaria in Sri Lanka

    Directory of Open Access Journals (Sweden)

    Karunaratne SHP Parakrama

    2008-08-01

    Full Text Available Abstract Background The current status of insecticide resistance and the underlying resistance mechanisms were studied in the major vector of malaria, Anopheles culicifacies, and the secondary vector, Anopheles subpictus in five districts (Anuradhapura, Kurunegala, Moneragala, Puttalam and Trincomalee of Sri Lanka. Eight other anophelines, Anopheles annularis, Anopheles barbirostris, Anopheles jamesii, Anopheles nigerrimus, Anopheles peditaeniatus, Anopheles tessellatus, Anopheles vagus and Anopheles varuna from Anuradhapura district were also tested. Methods Adult females were exposed to the WHO discriminating dosages of DDT, malathion, fenitrothion, propoxur, λ-cyhalothrin, cyfluthrin, cypermethrin, deltamethrin, permethrin and etofenprox. The presence of metabolic resistance by esterase, glutathione S-transferase (GST and monooxygenase-based mechanisms, and the sensitivity of the acetylcholinesterase target site were assessed using synergists, and biochemical, and metabolic techniques. Results All the anopheline species had high DDT resistance. All An. culicifacies and An. subpictus populations were resistant to malathion, except An. culicifacies from Kurunegala, where there was no malathion carboxylesterase activity. Kurunegala and Puttalam populations of An. culicifacies were susceptible to fenitrothion. All the An. culicifacies populations were susceptible to carbamates. Both species were susceptible to the discriminating dosages of cypermethrin and cyfluthrin, but had different levels of resistance to other pyrethroids. Of the 8 other anophelines, only An. nigerrimus and An. peditaeniatus were resistant to all the insecticides tested, probably due to their high exposure to the insecticides used in agriculture. An. vagus showed some resistance to permethrin. Esterases, GSTs and monooxygenases were elevated in both An. culicifacies and An. subpictus. AChE was most sensitive to insecticides in Kurunegala and Trincomalee An. culicifacies

  8. Efficient uptake of blood-borne BK and JC polyomavirus-like particles in endothelial cells of liver sinusoids and renal vasa recta.

    Directory of Open Access Journals (Sweden)

    Jaione Simon-Santamaria

    Full Text Available Liver sinusoidal endothelial cells (LSECs are specialized scavenger cells that mediate high-capacity clearance of soluble waste macromolecules and colloid material, including blood-borne adenovirus. To explore if LSECs function as a sink for other viruses in blood, we studied the fate of virus-like particles (VLPs of two ubiquitous human DNA viruses, BK and JC polyomavirus, in mice. Like complete virions, VLPs specifically bind to receptors and enter cells, but unlike complete virions, they cannot replicate. 125I-labeled VLPs were used to assess blood decay, organ-, and hepatocellular distribution of ligand, and non-labeled VLPs to examine cellular uptake by immunohisto- and -cytochemistry. BK- and JC-VLPs rapidly distributed to liver, with lesser uptake in kidney and spleen. Liver uptake was predominantly in LSECs. Blood half-life (∼1 min, and tissue distribution of JC-VLPs and two JC-VLP-mutants (L55F and S269F that lack sialic acid binding affinity, were similar, indicating involvement of non-sialic acid receptors in cellular uptake. Liver uptake was not mediated by scavenger receptors. In spleen, the VLPs localized to the red pulp marginal zone reticuloendothelium, and in kidney to the endothelial lining of vasa recta segments, and the transitional epithelium of renal pelvis. Most VLP-positive vessels in renal medulla did not express PV-1/Meca 32, suggesting location to the non-fenestrated part of vasa recta. The endothelial cells of these vessels also efficiently endocytosed a scavenger receptor ligand, formaldehyde-denatured albumin, suggesting high endocytic activity compared to other renal endothelia. We conclude that LSECs very effectively cleared a large fraction of blood-borne BK- and JC-VLPs, indicating a central role of these cells in early removal of polyomavirus from the circulation. In addition, we report the novel finding that a subpopulation of endothelial cells in kidney, the main organ of polyomavirus persistence, showed

  9. 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

    likelihood of reintroduction of the disease. METHODS: The following data were used: the database of the Entomology Group of the National Health Foundation, Santa Catarina (ACCES, 1997-2000; the epidemiological surveillance information system of the Health Surveillance Department (Malaria/SC; and the notifiable disease information system (SINAN/SC. These data were transferred to and analyzed in the Microsoft Office Excel 2007 software. RESULTS: Collections were carried out in 48 municipalities and 159 localities, and 12,310 culicids, 11,546 anophelines (93.7% and 764 others (6.2% were identified. Three subgenera and 13 species of anophelines were identified. CONCLUSIONS: Given that in the municipalities investigated, important vectors such as Anopheles cruzii and Anopheles albitasis were found to be present, with movements of infected individuals from endemic areas, these areas can be considered to be receptive and vulnerable to malaria. These species are suspected of being responsible for malaria transmission in this region, especially in the municipalities of Gaspar, Indaial and Rodeio.

  10. Mosquito mass rearing technology: a cold-water vortex device for continuous unattended separation of Anopheles arabiensis pupae from larvae.

    Science.gov (United States)

    Balestrino, Fabrizio; Gilles, Jérémie R L; Soliban, Sharon M; Nirschl, Anton; Benedict, Quentin E; Benedict, Mark Q

    2011-09-01

    In mass rearing of anopheline mosquitoes, pupae are usually separated from larvae on a daily basis to prevent unwanted adult emergence from trays. Depending on the device and species, 2 physical characteristics have most often been used for separation: buoyant density and size. In this report, we describe a system for continuous separation of Anopheles arabiensis larvae from pupae based on the natural difference in buoyant density and behavior between the 2 stages. We determined that temperatures 4-15 degrees C caused neither mortality nor reduction in likelihood of pupation or emergence. Separation improved as temperatures decreased down to 4 degrees C. We devised and demonstrated a 15 degrees C water vortex separator that we anticipate can process approximately 1 million larvae and pupae per hour with a < 0.3% pupal contamination rate and which operates unattended.

  11. Transglutaminase-mediated semen coagulation controls sperm storage in the malaria mosquito.

    Directory of Open Access Journals (Sweden)

    David W Rogers

    2009-12-01

    Full Text Available Insect seminal fluid proteins are powerful modulators of many aspects of female physiology and behaviour including longevity, egg production, sperm storage, and remating. The crucial role of these proteins in reproduction makes them promising targets for developing tools aimed at reducing the population sizes of vectors of disease. In the malaria mosquito Anopheles gambiae, seminal secretions produced by the male accessory glands (MAGs are transferred to females in the form of a coagulated mass called the mating plug. The potential of seminal fluid proteins as tools for mosquito control demands that we improve our limited understanding of the composition and function of the plug. Here, we show that the plug is a key determinant of An. gambiae reproductive success. We uncover the composition of the plug and demonstrate it is formed through the cross-linking of seminal proteins mediated by a MAG-specific transglutaminase (TGase, a mechanism remarkably similar to mammalian semen coagulation. Interfering with TGase expression in males inhibits plug formation and transfer, and prevents females from storing sperm with obvious consequences for fertility. Moreover, we show that the MAG-specific TGase is restricted to the anopheline lineage, where it functions to promote sperm storage rather than as a mechanical barrier to re-insemination. Taken together, these data represent a major advance in our understanding of the factors shaping Anopheles reproductive biology.

  12. Seasonal distribution, biology, and human attraction patterns of mosquitoes (Diptera: Culicidae) in a rural village and adjacent forested site near Iquitos, Peru.

    Science.gov (United States)

    Turell, Michael J; Sardelis, Michael R; Jones, James W; Watts, Douglas M; Fernandez, Roberto; Carbajal, Faustino; Pecor, James E; Klein, Terry A

    2008-11-01

    This study was conducted as part of a field-ecology study of arboviral and malarial activity in the Amazon Basin, Loreto Department, Peru, to determine the relative abundance, species diversity, and seasonal and vertical distributions of potential mosquito vectors. Mosquitoes were captured either by volunteers using mouth aspirators while mosquitoes attempted to land on the collectors or in dry ice-baited ABC light traps. Anopheles darlingi, the principal malaria vector in the region, was the most commonly captured anopheline mosquito in Puerto Almendra village (99%) while landing on humans, with a mean of 37.1 mosquitoes captured per 24-h period, representing nearly one half of all mosquitoes collected. An. darlingi human landing activity began shortly after sunset, peaked at 2000-2100 hours, and declined gradually until sunrise. This species readily entered houses, because 51% of the An. darlingi captured by paired collectors, stationed inside and outside houses, were captured indoors. Human landing collections provided a more accurate estimate of human attraction of An. darlingi, capturing 30 times as many as co-located dry ice-baited ABC light traps. In contrast, eight times as many Culex (Melanoconion) species, including known arbovirus vectors, were captured in light traps as by co-located human collectors. Despite being located within 300 m of the village collection site, only a few Anopheles species were captured at the forest collection site, including only 0.1 An darlingi/ 24 h, thus indicating that An. darlingi activity was directly associated with the rural village. These data provide a better understanding of the taxonomy, population density, and seasonal distribution of potential mosquito vectors of disease within the Amazon Basin region and allow for the development of appropriate vector and disease prevention strategies that target vector populations.

  13. The effect of deltamethrin-treated net fencing around cattle enclosures on outdoor-biting mosquitoes in Kumasi, Ghana.

    Science.gov (United States)

    Maia, Marta Ferreira; Abonuusum, Ayimbire; Lorenz, Lena Maria; Clausen, Peter-Henning; Bauer, Burkhard; Garms, Rolf; Kruppa, Thomas

    2012-01-01

    Classic vector control strategies target mosquitoes indoors as the main transmitters of malaria are indoor-biting and -resting mosquitoes. However, the intensive use of insecticide-treated bed-nets (ITNs) and indoor residual spraying have put selective pressure on mosquitoes to adapt in order to obtain human blood meals. Thus, early-evening and outdoor vector activity is becoming an increasing concern. This study assessed the effect of a deltamethrin-treated net (100 mg/m(2)) attached to a one-meter high fence around outdoor cattle enclosures on the number of mosquitoes landing on humans. Mosquitoes were collected from four cattle enclosures: Pen A - with cattle and no net; B - with cattle and protected by an untreated net; C - with cattle and protected by a deltamethrin-treated net; D - no cattle and no net. A total of 3217 culicines and 1017 anophelines were collected, of which 388 were Anopheles gambiae and 629 An. ziemanni. In the absence of cattle nearly 3 times more An. gambiae (p<0.0001) landed on humans. The deltamethrin-treated net significantly reduced (nearly three-fold, p<0.0001) culicine landings inside enclosures. The sporozoite rate of the zoophilic An. ziemanni, known to be a secondary malaria vector, was as high as that of the most competent vector An. gambiae; raising the potential of zoophilic species as secondary malaria vectors. After deployment of the ITNs a deltamethrin persistence of 9 months was observed despite exposure to African weather conditions. The outdoor use of ITNs resulted in a significant reduction of host-seeking culicines inside enclosures. Further studies investigating the effectiveness and spatial repellence of ITNs around other outdoor sites, such as bars and cooking areas, as well as their direct effect on vector-borne disease transmission are needed to evaluate its potential as an appropriate outdoor vector control tool for rural Africa.

  14. How mosquitoes fly in the rain

    Science.gov (United States)

    Dickerson, Andrew; Shankles, Peter; Madhavan, Nihar; Hu, David

    2011-11-01

    Mosquitoes thrive during rainfall and high humidity. If raindrops are 50 times heavier than mosquitoes, how do mosquitoes fly in the rain? In this combined experimental and theoretical study, we measure the impact force between a falling drop and a free-flying mosquito. High-speed videography of mosquitoes and custom-built mimics reveals a mosquito's low inertia renders it impervious to falling drops. Drops do not splash on mosquitoes, but simply push past them allowing a mosquito to continue on its flight path undeterred. We rationalize the force imparted using scaling relations based on the time of rebound between a falling drop and a free body of significantly less mass.

  15. Ultrastructural studies of mosquito ovogenesis.

    Science.gov (United States)

    Soumaré, M L; Ndiaye, M

    2005-04-01

    The ovogenesis of four mosquito species belonging to the genera Aedes, Anopheles and Culex, are investigated using Electron microscopes. Three ovogenetic phases named previtellogenesis, vitellogenesis, postvitellogenesis and mature eggs are described using transmission electron and light microscopes. Egg ornamentations are described with scanning electron microscopy. The controversial nomenclature of the mosquito egg envelopes is discussed.

  16. Characterization of water bodies for mosquito habitat using a multi-sensor approach

    Science.gov (United States)

    Midekisa, A.; Wimberly, M. C.; Senay, G. B.

    2012-12-01

    potential breeding habitats for anopheline mosquitoes. The resulting products are useful for public health decision making towards effective prevention and control of the malaria burden in the Amhara region of Ethiopia.

  17. Seasonal Abundance and Host-Feeding Patterns of Anopheline Vectors in Malaria Endemic Area of Iran

    Directory of Open Access Journals (Sweden)

    Hamidreza Basseri

    2010-01-01

    Full Text Available Seasonal abundance and tendency to feed on humans are important parameters to measure for effective control of malaria vectors. The objective of this study was to describe relation between feeding pattern, abundance, and resting behavior of four malaria vectors in southern Iran. This study was conducted in ten indicator villages (based on malaria incidence and entomological indices in mountainous/hilly and plain regions situated south and southeastern Iran. Mosquito vectors were collected from indoor as well as outdoor shelters and the blood meals were examined by ELISA test. Over all 7654 female Anopheles spp. were captured, the most common species were Anopheles stephensi, An. culicifacies, An. fluviatilis, and An. d'thali. The overall human blood index was 37.50%, 19.83%, 16.4%, and 30.1% for An. fluviatilis, An. stephensi, An. culicifacies, and An. d'thali, respectively. In addition, An. fluviatilis fed on human blood during the entire year but the feeding behavior of An. stephensi and An. culicifacies varied according to seasons. Overall, the abundance of the female mosquito positive to human blood was 4.25% per human shelter versus 17.5% per animal shelter. This result indicates that the vectors had tendency to rest in animal shelters after feeding on human. Therefore, vector control measure should be planned based on such as feeding pattern, abundance, and resting behavior of these vectors in the area.

  18. Mosquitoes: A Resource Book for the Classroom.

    Science.gov (United States)

    Gillmor, Mary S.; And Others

    This booklet was written for anyone interested in growing mosquitoes and experimenting with them. There are three major sections: (1) rationale for studying mosquitoes, (2) raising mosquitoes, and (3) some scientific findings. The first section describes basic information about mosquitoes. The second section includes information about materials,…

  19. Seasonal population changes and malaria transmission potential of Anopheles pharoensis and the minor anophelines in Mwea Irrigation Scheme, Kenya.

    Science.gov (United States)

    Mukiama, T K; Mwangi, R W

    1989-05-01

    A study in 1984 and 1985 showed that Anopheles gambiae s.l. and An. pharoensis were the major anophelines in Mwea Irrigation Scheme, Kenya, constituting 83.86% and 15.69% of the catch respectively. Four minor species made up the remaining 0.45%. The irrigation phase of the rice cultivation cycle in August, which linked the flooding effects of the two rainy seasons, resulted in major population increases of An. pharoensis and enabled continuous breeding for up to 9 months per year. The average of mean monthly proportions of unfed, bloodfed, and gravid females was 26.6, 58.8, and 14.6% respectively. The Plasmodium falciparum sporozoite rates for An. pharoensis were 1.3% by ELISA and 0.68% by dissection, while those for An. funestus were 1.7% by ELISA and 1.25% by dissection. An. pharoensis can contribute to the epidemiology of Malaria in the Mwea area.

  20. THE CONTROL OF ANOPHELINE MOSQUITOS BY THE SPRAYING OF DELTAMETHRIN ON RAFFIA CURTAINS USED IN MINERS' HUTS IN AREAS ENDEMIC FOR MALARIA

    Directory of Open Access Journals (Sweden)

    FIGUEIREDO Regina

    1998-01-01

    Full Text Available The residual potential of an aqueous solution of Deltamethrin (FW 25 mg i.a./m2 was evaluated on raffia curtains. These are sheets of synthetic material used in the construction of huts to house miners. Experiments were conducted during 420 days and the curtains were always rolled up in the daytime and unrolled in late afternoon. Data analyzed by logarithmic regression indicated that raffia treated with Deltamethrin had higher mortality indices than that covered with DDT. The residual capacity of Deltamethrin on raffia was high. The mortality percentage was above 85% after 360 days and dropped to about 50% at 420 days. The effect of DDT was reduced after 180 days and reached zero by the end of the experiment. Based on the results of these experiments, it is recommended that Deltamethrin be used to spray raffia curtains in mining regions and other areas that are endemic for malaria.

  1. Optimización de superficies metamateriales para su aplicación en el diseño de estructuras sintonizables reductoras de la sección recta radar

    OpenAIRE

    Hernández Gómez, Ismael

    2015-01-01

    En este proyecto final de carrera se propone una mejora de la estructura chessboard. Se ha estudiado la viabilidad de hacer sintonizable una estructura variando el valor de la permitividad del substrato, para poder aumentar el ancho de banda en el que el chessboard reduce la sección recta radar. Se ha estudiado también que posibles tecnologías de sintonización se podían implementar, como cristales líquidos o BST. El proyecto comienza con un estudio de diferentes tipos de AMC para comprobar si...

  2. RNA Interference for Mosquito and Mosquito-Borne Disease Control

    Directory of Open Access Journals (Sweden)

    Paul M. Airs

    2017-01-01

    Full Text Available RNA interference (RNAi is a powerful tool to silence endogenous mosquito and mosquito-borne pathogen genes in vivo. As the number of studies utilizing RNAi in basic research grows, so too does the arsenal of physiological targets that can be developed into products that interrupt mosquito life cycles and behaviors and, thereby, relieve the burden of mosquitoes on human health and well-being. As this technology becomes more viable for use in beneficial and pest insect management in agricultural settings, it is exciting to consider its role in public health entomology. Existing and burgeoning strategies for insecticide delivery could be adapted to function as RNAi trigger delivery systems and thereby expedite transformation of RNAi from the lab to the field for mosquito control. Taken together, development of RNAi-based vector and pathogen management techniques & strategies are within reach. That said, tools for successful RNAi design, studies exploring RNAi in the context of vector control, and studies demonstrating field efficacy of RNAi trigger delivery have yet to be honed and/or developed for mosquito control.

  3. Botanicals as Mosquito Larvicides

    Directory of Open Access Journals (Sweden)

    D.R. Nath,

    2006-10-01

    Full Text Available Methanol extracts of 19 indigenous plants were evaluated as mosquito larvicide. Amongthese, pericarp of Zanthoxylum limonella was found to have the most promising larvicidalproperties against Aedes(s albopictus and Culex quinquefasciatus with LC90 values at 0.47 ppmand 0.73 ppm, respectively. The extract of Piper nigrum was also found very effective (LC90on the larvae of both the species at 6.8 ppm and 8.4 ppm, respectively. The extracts of theremaining plant parts showed LC90 values at above 100 ppm concentration. Extract of Calotropisgigantea was found to be the least effective ( LC90 values at 962.8 ppm and 1091.8 ppm againstthe larvae of both the species. However, plant extracts were found more effective against Aedes(salbopictus larvae than against Culex quinquefasciatus larvae.

  4. Heritability of Attractiveness to Mosquitoes

    Science.gov (United States)

    Fernández-Grandon, G. Mandela; Gezan, Salvador A.; Armour, John A. L.; Pickett, John A.; Logan, James G.

    2015-01-01

    Female mosquitoes display preferences for certain individuals over others, which is determined by differences in volatile chemicals produced by the human body and detected by mosquitoes. Body odour can be controlled genetically but the existence of a genetic basis for differential attraction to insects has never been formally demonstrated. This study investigated heritability of attractiveness to mosquitoes by evaluating the response of Aedes aegypti (=Stegomyia aegypti) mosquitoes to odours from the hands of identical and non-identical twins in a dual-choice assay. Volatiles from individuals in an identical twin pair showed a high correlation in attractiveness to mosquitoes, while non-identical twin pairs showed a significantly lower correlation. Overall, there was a strong narrow-sense heritability of 0.62 (SE 0.124) for relative attraction and 0.67 (0.354) for flight activity based on the average of ten measurements. The results demonstrate an underlying genetic component detectable by mosquitoes through olfaction. Understanding the genetic basis for attractiveness could create a more informed approach to repellent development. PMID:25901606

  5. Mosquito Traps: An Innovative, Environmentally Friendly Technique to Control Mosquitoes

    Directory of Open Access Journals (Sweden)

    Brigitte Poulin

    2017-03-01

    Full Text Available We tested the use of mosquito traps as an alternative to spraying insecticide in Camargue (France following the significant impacts observed on the non-target fauna through Bti persistence and trophic perturbations. In a village of 600 inhabitants, 16 Techno Bam traps emitting CO2 and using octenol lures were set from April to November 2016. Trap performance was estimated at 70% overall based on mosquitoes landing on human bait in areas with and without traps. The reduction of Ochlerotatus caspius and Oc. detritus, the two species targeted by Bti spraying, was, respectively, 74% and 98%. Traps were less efficient against Anopheles hyrcanus (46%, which was more attracted by lactic acid than octenol lures based on previous tests. Nearly 300,000 mosquitoes from nine species were captured, with large variations among traps, emphasizing that trap performance is also influenced by surrounding factors. Environmental impact, based on the proportion of non-target insects captured, was mostly limited to small chironomids attracted by street lights. The breeding success of a house martin colony was not significantly affected by trap use, in contrast to Bti spraying. Our experiment confirms that the deployment of mosquito traps can offer a cost-effective alternative to Bti spraying for protecting local populations from mosquito nuisance in sensitive natural areas.

  6. Officials: Aerial Spraying Working Against Miami Mosquitoes

    Science.gov (United States)

    ... 160274.html Officials: Aerial Spraying Working Against Miami Mosquitoes The insects are to blame for first cases ... 2016 (HealthDay News) -- Aerial spraying is killing many mosquitoes in a part of Miami where the insects ...

  7. Heterologous expression in transgenic mosquitoes

    Institute of Scientific and Technical Information of China (English)

    Santhosh P K; Yu hua Deng; Weidong Gu; Xiaoguang Chen

    2010-01-01

    Arthropod-borne diseases such as malaria and dengue virus afflict billions of people worldwide imposing major economic and social burdens. Control of such pathogens is mainly performed by vector management and treatment of affected individuals with drugs. The failure of these conventional approaches due to emergence of insecticide-resistant insects and drug-resistant parasites demonstrate the need of novel and efficacious control strategies to combat these diseases. Genetic modification(GM) of mosquito vectors to impair their ability to be infected and transmit pathogens has emerged as a new strategy to reduce transmission of many vector-borne diseases and deliver public health gains. Several advances in developing transgenic mosquitoes unable to transmit pathogens have gained support, some of them attempt to manipulate the naturally occurring endogenous refractory mechanisms, while others initiate the identification of an exogenous foreign gene which disrupt the pathogen development in insect vectors. Heterologous expression of transgenes under a native or heterologous promoter is important for the screening and effecting of the transgenic mosquitoes. The effect of the transgene on mosquito fitness is a crucial parameter influencing the success of this transgenic approach. This review examines these two aspects and describes the basic research work that has been accomplished towards understanding the complex relation between the parasite and its vector and focuses on recent advances and perspectives towards construction of transgenic mosquitoes refractory to vector-borne disease transmission.

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

    Directory of Open Access Journals (Sweden)

    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

  9. Ecology of larval mosquitoes, with special reference to Anopheles arabiensis (Diptera: Culcidae) in market-garden wells in urban Dakar, Senegal.

    Science.gov (United States)

    Robert, V; Awono-Ambene, H P; Thioulouse, J

    1998-11-01

    The urban area of Dakar, Senegal, contains > 5,000 market-garden wells that provide permanent sites for mosquito larvae, in particular Anopheles arabiensis Patton, the major vector of malaria. A study of the bioecology of mosquito larvae was conducted over 1 yr with a monthly visit to 48 of these wells. Overall, 9,589 larvae were collected of which 80.1% were Culicinae and 11.9% Anophelinae. Larvae from stages III and IV (n = 853) were identified to 10 species. An. arabiensis represented 86% of the anophelines collected and An. ziemanni Grunberg 14%. The most common Culicinae species included Aedeomyia africana Neveu-Lemaire, Culex quinquefasciatus Say, and Mimomyia splendens Theobald. Maximum anopheline abundance was observed at the end of the dry season in June, whereas maximum Culicinae abundance was observed at the end of the rainy season in September. Most wells (67%) did not harbor any An. arabiensis larvae and in the remaining 33% the larval abundance was low, averaging 0.54 larvae in stages III-IV per tray sample. To identify factors that determine the abundance of larvae in these wells, a co-inertia (multivariate) analysis was carried out to account for physicochemical variables (depth, turbidity, temperature, pH, conductivity, Na+, Cl-, HCO3-, CO3--, and NO3- concentrations) and biological variables (abundance of mosquito species, predators [e.g., fish, Dytiscidae, Notonectidae, odonates], molluscs [Bulinus and Biomphalaria], and surface plants [water lettuce, Lemna, and filamentous algae]). The co-inertia analysis indicated that the abundance of An. arabiensis was associated with Cx. quinquefasciatus and Cx. decens for the physiochemical data but was not associated with other mosquito species for floro-faunistic data. The conditions associated with abundant An. arabiensis were warm temperature (28-30 degrees C), clear and not too deep water (odonates), the presence of water lettuce, and an absence of Lemna. These results indicate that many contributing

  10. Rural buyers' perception about mosquito repellants

    OpenAIRE

    Mehta, D.; Anand GARG; Naveen K MEHTA

    2010-01-01

    Mosquito repellants prevent mosquito bites and prevention of "man-mosquito contact" is a critical factor in transmission and spread of any disease through mosquitoes particularly in rural area. There has been a long standing 'bias' towards rural buyers. The rural markets are considered rigid in the nature but it is not the case in real sense. Marketing to rural buyers is not only a challenge to the marketers but to the manufacturers, communicators, national planners and economists as well. Th...

  11. Efficacy and efficiency of new Bacillus thuringiensis var. israelensis and Bacillus sphaericus formulations against Afrotropical anophelines in Western Kenya

    NARCIS (Netherlands)

    Fillinger, U.; Knols, B.G.J.; Becker, N.

    2002-01-01

    We evaluated the efficacy of new water-dispersible granular (WDG) formulations of Bacillus thuringienis var. israelensis (Bti; VectoBac?) and B. sphaericus (Bs; VectoLex?, Valent BioScience Corp., Illinois, USA) for the control of larval Anopheles gambiae sensu lato Giles mosquitoes in a malaria-end

  12. Looking Backward, Looking Forward: The Long, Torturous Struggle with Mosquitoes

    Directory of Open Access Journals (Sweden)

    Gordon M. Patterson

    2016-10-01

    Full Text Available The American anti-mosquito movement grew out of the discovery of the role of mosquitoes in transferring pathogens and public concern about pest and nuisance mosquitoes in the late 1800s. In the 20th century, organized mosquito control in the United States passed through three eras: mechanical, chemical, and integrated mosquito control. Mosquito control in the 21st century faces the challenge of emerging pathogens, invasive mosquito species, and balancing concerns about the environment with effective control strategies.

  13. Mosquito population dynamic (diptera: culicidae in a eutrophised dam

    Directory of Open Access Journals (Sweden)

    ED. Wermelinger

    Full Text Available This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three parts (P1, P2 and P3, each part being 3 m long. P1 did not have vegetation (grass along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823 (83% and 40.6%, Anopheles (Nyssorhynchus evansae (Brèthes, 1926 (92% and 26.7%, Anopheles (Nyssorhynchus rangeli (Gabaldon, Cova Garcia and Lopez, 1940 (83% and 14.3% and Culex nigripalpus (Theobald, 1901 (33% and 18.4%. C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%, May/June/July (75%, Aug./Sept./Oct. (29.4% and Aug./Sept./Oct. (23.5% particularly in the months of December (88.4% Sept.tember (48.94, (38.3 and August (47.62 respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L and of total Phosphorus (0.02 mg/L are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli and Culex species (C. quinquefasciatus + C. nigripalpis between P1 and P2 (χ² = 0.0097, P1 and P3 (χ² = 0.0005, but not between P2 and P3 (χ² = 0.2045.The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.

  14. Mosquito population dynamic (Diptera: Culicidae) in a eutrophised dam.

    Science.gov (United States)

    Wermelinger, E D; Benigno, C V; Machado, R N M; Cabello, P H; Meira, A M; Ferreira, A P; Zanuncio, J C

    2012-11-01

    This study observed the mosquito population in a rural eutrophised dam. Larvae of L3 and L4 stages and pupae were dipped out during twelve month collections and the reared to the adult stage for identification. The collections were done along nine metres from the edge of the dam divided in three parts (P1, P2 and P3), each part being 3 m long. P1 did not have vegetation (grass) along its edge,which would reach or sink into the water to promote some shade on the marginal water. A total of 217 adults of four species was identified with the following constancies and frequencies: Culex quinquefasciatus (Say, 1823) (83% and 40.6%), Anopheles (Nyssorhynchus) evansae (Brèthes, 1926) (92% and 26.7%), Anopheles (Nyssorhynchus) rangeli (Gabaldon, Cova Garcia and Lopez, 1940) (83% and 14.3%) and Culex nigripalpus (Theobald, 1901) (33% and 18.4%). C. quinquefasciatus, A. evansae, A. rangeli and C. nigripalpus were more frequent in the quarters Nov./Dec./Jan. (85.7%), May/June/July (75%), Aug./Sept./Oct. (29.4%) and Aug./Sept./Oct. (23.5%) particularly in the months of December (88.4%) Sept.tember (48.94), (38.3) and August (47.62) respectively. The presence of C. quinquefasciatus and the high incidence of Daphinia sp. and also the levels of Organic Nitrogen (0.28 mg/L) and of total Phosphorus (0.02 mg/L) are indications of the eutrophication of the dam. There was a difference regarding the total of Anopheles (A. avansae + A. rangeli) and Culex species (C. quinquefasciatus + C. nigripalpis) between P1 and P2 (χ(2) = 0.0097), P1 and P3 (χ(2) = 0.0005), but not between P2 and P3 (χ(2) = 0.2045).The high C. quinquefasciatus constancy and frequency were confirmed to be a good biological indicator for a eutrophised environment and A. evansae showed a good potential for this environment. Vegetation can be an important factor for anopheline population dynamic also in eutrophic breeding sites.

  15. Anopheline species, some of their habits and relation to malaria in endemic areas of Rondônia State, Amazon region of Brazil Espécies de anofelinos, alguns de seus hábitos e relação com a malária, em áreas endênmicas do Estado de Rondônia, Amazônia brasileira

    Directory of Open Access Journals (Sweden)

    Ricardo Lourenço-de-Oliveira

    1989-12-01

    Full Text Available In view of recent studies incriminating several species of anophelines, besides Anopheles darlingi, as malaria vectors in the Brazilian Amazon, we performed an anopheline survey in four localities - Ariquemes, Cujubim, Machadinho and Itapoã do Oeste - in Rondônia, the most malarious State in the Country. Twenty species were found. An. darlingi was, by far, the dominant species and the only one whose density coincided with that of malaria. On human baits it was more numerous in the immediate vincinity of houses than indoors whre, however, it was almost the only species encountered. On both situations it fed mostly at sunset and during the first half of the night. It was less numerous far from houses and scarce inside the forest. Other species (An. triannulatus, An. evansae, An. albitarsis, An. strodei appeared in appreciable numbers only in Ariquemes, both in areas with and without malaria. The remaining species were scanty. An. darlingi was confirmed as the primary local vector.Como recentes estudos vêm incriminando diversas espécies de anofelinos como trasnmissores da malária na Amazônia brasileira além do Anopheles darlingi, realizamos um estudo sobre esse grupo de mosquitos em quatro localidades - Ariquemes, Cujubim, Machadinho e Itapoã do Oeste - no Estado de Rondônia, o mais malarígeno do país. Vinte espécies foram achadas. An. darlingi foi, de longe, a predominante e a única cuja densidade coincidiu com a da malária. Sugando iscas humanas, esse mosquito mostrou-se mais numeroso na imediata vizinhança das casas que em seu interior, onde, entretanto, foi quase a única espécie encontrada. Em ambas as situações picava principalmente ao crepúsculo vespertino e durante a primeira metade da noite, sendo menos freqüente longe das casas e escasso na floresta. Outras espécies, como An. triannulatus, An. evansae, An. albirarsis e An. strodei foram capturadas em números apreciáveis, somente em Ariquemes, em áreas com e sem mal

  16. Rural buyers' perception about mosquito repellants

    Directory of Open Access Journals (Sweden)

    D. MEHTA

    2010-06-01

    Full Text Available Mosquito repellants prevent mosquito bites and prevention of "man-mosquito contact" is a critical factor in transmission and spread of any disease through mosquitoes particularly in rural area. There has been a long standing 'bias' towards rural buyers. The rural markets are considered rigid in the nature but it is not the case in real sense. Marketing to rural buyers is not only a challenge to the marketers but to the manufacturers, communicators, national planners and economists as well. That is why it has been necessary to understand the various aspects of selected rural areas and consumption pattern for such a fast growing market i.e. mosquito repellants and rural buyers’ perception towards such urban products. The present paper aims to find out the factors influencing the purchase decisions of rural buyers for mosquito repellants and to study the perceptions of present and potential rural buyers' of selected mosquito repellant brands.

  17. Mosquito and Blackfly Category Manual.

    Science.gov (United States)

    Bowman, James S.; And Others

    This manual provides information needed to meet the standards for pesticide applicator certification. Section one is concerned with the morphology, life cycle and breeding areas of mosquitoes and the diseases resulting from their presence. The second section covers similar categories in relation to the black fly population. Calculation methods and…

  18. Approaches to passive mosquito surveillance in the EU

    NARCIS (Netherlands)

    Kampen, H.; Medlock, J.M.; Vaux, A.G.C.; Koenraadt, C.J.M.; Vliet, van A.J.H.; Bartumeus, F.; Oltra, A.; Sousa, C.A.; Chouin, S.; Werner, D.

    2015-01-01

    The recent emergence in Europe of invasive mosquitoes and mosquito-borne disease associated with both invasive and native mosquito species has prompted intensified mosquito vector research in most European countries. Central to the efforts are mosquito monitoring and surveillance activities in order

  19. Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes

    Directory of Open Access Journals (Sweden)

    N. Lukwa

    2013-04-01

    Full Text Available The effect of permethrin-treated Africa University (AU mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ≥80% of mosquitoes after a number of washes and repellence (ability to prevent ≥80% of mosquito bites properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up to 20 washes, declining to 90% after 25 washes. Untreated AU blankets did not cause any mortality on mosquitoes. However, mosquito repellence was 96%, 94%, 97.9%, 87%, 85% and 80.7% for treated AU blankets washed 0, 5, 10, 15, 20 and 25 times, respectively. Mosquito repellence was consistently above 80% from 0-25 washes. In conclusion, AU blankets washed 25 times were effective in repelling and killing An. gambiae sl mosquitoes under laboratory conditions.

  20. Mosquito transgenesis: what is the fitness cost?

    Science.gov (United States)

    Marrelli, Mauro T; Moreira, Cristina K; Kelly, David; Alphey, Luke; Jacobs-Lorena, Marcelo

    2006-05-01

    The generation of transgenic mosquitoes with a minimal fitness load is a prerequisite for the success of strategies for controlling mosquito-borne diseases using transgenic insects. It is important to assemble as much information as possible on this subject because realistic estimates of transgene fitness costs are essential for modeling and planning release strategies. Transgenic mosquitoes must have minimal fitness costs, because such costs would reduce the effectiveness of the genetic drive mechanisms that are used to introduce the transgenes into field mosquito populations. Several factors affect fitness of transgenic mosquitoes, including the potential negative effect of transgene products and insertional mutagenesis. Studies to assess fitness of transgenic mosquitoes in the field (as opposed to the laboratory) are still needed.

  1. Wash resistance and repellent properties of Africa University mosquito blankets against mosquitoes

    OpenAIRE

    N. Lukwa; A. Makuwaza; T. Chiwade; Mutambu, S L; M. Zimba; P. Munosiyei

    2013-01-01

    The effect of permethrin-treated Africa University (AU) mosquito blankets on susceptible female Anopheles gambiae sensu lato mosquitoes was studied under laboratory conditions at Africa University Campus in Mutare, Zimbabwe. Wash resistance (ability to retain an effective dose that kills ≥80% of mosquitoes after a number of washes) and repellence (ability to prevent ≥80% of mosquito bites) properties were studied. The AU blankets were wash resistant when 100% mortality was recorded up t...

  2. Green Nanoparticles for Mosquito Control

    OpenAIRE

    Namita Soni; Soam Prakash

    2014-01-01

    Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicum or C. verum J. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquef...

  3. Improvised microinjection technique for mosquito vectors

    OpenAIRE

    Sampath, Kumar S.; H.P.Puttaraju

    2012-01-01

    Background & objectives: Bio-manipulation technique is of primary importance during the development of transgenic mosquitoes. The study describes the variable factors that influence the viability of medically important mosquito vectors during microinjection. Methods: Three mosquito vectors belonging to the genus Aedes, Anopheles and Culex were microinjected at different developmental stages of their life cycle viz., egg, larvae, pupae and adult. Results: The improvisations revealed an increas...

  4. Entomopathogenic fungi for mosquito control: A review

    OpenAIRE

    Ernst-Jan Scholte; KNOLS, BART G. J.; Samson, Robert A.; Willem Takken

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito...

  5. The impact of transgenic mosquitoes on dengue virulence to humans and mosquitoes.

    Science.gov (United States)

    Medlock, Jan; Luz, Paula M; Struchiner, Claudio J; Galvani, Alison P

    2009-10-01

    Dengue is a major public health concern in the tropics and subtropics. Innovative transgenic strategies to render Aedes aegypti mosquitoes, the primary vector of dengue, incompetent for dengue transmission are under development. We modeled the evolutionary impact of different transgenic mosquito strategies on dengue-induced mortality, that is, dengue virulence, to both humans and mosquitoes. This model incorporates various evolutionary trade-offs in dengue virus epidemiological traits, for example, a trade-off between dengue transmission rate and its virulence to humans. Our results indicate that strategies that block transmission or reduce mosquito biting impose selection on dengue virulence in humans. This selection can be for either higher or lower virulence, depending on the interaction between the effect of the transgene and the trade-offs in epidemiological traits, highlighting the need for detailed quantitative data to understand more fully the impact of mosquito transgenesis on dengue virulence. Dengue virulence in mosquitoes can be selected on by transgenic strategies of blocking transmission, decreased mosquito biting, increased mosquito background mortality, and increased mosquito infection-induced mortality. Our results suggest that dengue control strategies that raise mosquito background mortality or mosquito infection-induced mortality pose less risk of causing increased virulence to humans than strategies that block transmission or reduce mosquito biting.

  6. Modeling Mosquito Distribution. Impact of the Landscape

    Science.gov (United States)

    Dumont, Y.

    2011-09-01

    In order to use efficiently vector control tools, like insecticides, and mechanical control, it is necessary to provide mosquito density estimate and mosquito distribution, taking into account the environment and entomological knowledges. Mosquito dispersal modeling, together with a compartmental approach, leads to a quasilinear parabolic system. Using the time splitting approach and appropriate numerical methods for each operator, we construct a reliable numerical scheme. Considering various landscapes, we show that the environment can have a strong influence on mosquito distribution and, thus, in the efficiency or not of vector control.

  7. Spatio-temporal Modeling of Mosquito Distribution

    Science.gov (United States)

    Dumont, Y.; Dufourd, C.

    2011-11-01

    We consider a quasilinear parabolic system to model mosquito displacement. In order to use efficiently vector control tools, like insecticides, and mechanical control, it is necessary to provide density estimates of mosquito populations, taking into account the environment and entomological knowledges. After a brief introduction to mosquito dispersal modeling, we present some theoretical results. Then, considering a compartmental approach, we get a quasilinear system of PDEs. Using the time splitting approach and appropriate numerical methods for each operator, we construct a reliable numerical scheme. Considering vector control scenarii, we show that the environment can have a strong influence on mosquito distribution and in the efficiency of vector control tools.

  8. Entomopathogenic fungi for mosquito control: A review

    Directory of Open Access Journals (Sweden)

    Ernst-Jan Scholte

    2004-06-01

    Full Text Available Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis.

  9. Entomopathogenic fungi for mosquito control: a review.

    Science.gov (United States)

    Scholte, Ernst-Jan; Knols, Bart G J; Samson, Robert A; Takken, Willem

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito populations, and have been studied extensively. There are, however, many other fungi that infect and kill mosquitoes at the larval and/or adult stage. The discovery, in 1977, of the selective mosquito-pathogenic bacterium Bacillus thuringiensis Berliner israelensis (Bti) curtailed widespread interest in the search for other suitable biological control agents. In recent years interest in mosquito-killing fungi is reviving, mainly due to continuous and increasing levels of insecticide resistance and increasing global risk of mosquito-borne diseases. This review presents an update of published data on mosquito-pathogenic fungi and mosquito-pathogen interactions, covering 13 different fungal genera. Notwithstanding the potential of many fungi as mosquito control agents, only a handful have been commercialized and are marketed for use in abatement programs. We argue that entomopathogenic fungi, both new and existing ones with renewed/improved efficacies may contribute to an expansion of the limited arsenal of effective mosquito control tools, and that they may contribute in a significant and sustainable manner to the control of vector-borne diseases such as malaria, dengue and filariasis.

  10. Anopheline species, some of their habits and relation to malaria in endemic areas of Rondônia State, Amazon region of Brazil.

    Science.gov (United States)

    Lourenço-de-Oliveira, R; Guimarães, A E; Arlé, M; da Silva, T F; Castro, M G; Motta, M A; Deane, L M

    1989-01-01

    In view of recent studies incriminating several species of anophelines, besides Anopheles darlingi, as malaria vectors in the Brazilian Amazon, we performed an anopheline survey in four localities--Ariquemes, Cujubim, Machadinho and Itapoã do Oeste--in Rondônia, the most malarious State in the Country. Twenty species were found. An. darlingi was, by far, the dominant species and the only one whose density coincided with that of malaria. On human baits it was more numerous in the immediate vicinity of houses than indoors where, however, it was almost the only species encountered. On both situations it fed mostly at sunset and during the first half of the night. It was less numerous far from houses and scarce inside the forest. Other species (An. triannulatus, An. evansae, An. albitarsis, An. strodei) appeared in appreciable numbers only in Ariquemes, both in areas with and without malaria. The remaining species were scanty. An. darlingi was confirmed as the primary local vector.

  11. Aggressive mosquito fauna and malaria transmission in a forest area targeted for the creation of an agro-industrial complex in the south of Cameroon

    Directory of Open Access Journals (Sweden)

    P. Ntonga Akono

    2016-12-01

    Full Text Available Baseline entomological information should be collected before the implementation of industrial projects in malaria endemic areas. This allows for subsequent monitoring and evaluation of the project impact on malaria vectors. This study aimed at assessing the vectorial system and malaria transmission in two ecologically different villages of the South-Cameroon forest bloc targeted for the creation of an agro-industrial complex. For four consecutive seasons in 2013, adult mosquitoes were captured using Human Landing Catch in NDELLE village (located along a main road in a degraded forest with many fish ponds and KOMBO village (located 5km far from the main road in a darker forest and crossed by the Mvobo River. Morpho-taxonomic techniques were used alongside molecular techniques for the identification of mosquito species. ELISA test was used for the detection of circumsporozoite protein antigen of Plasmodium falciparum. Mosquito biting rate was higher in NDELLE than in KOMBO (28.18 versus 17.34 bites per person per night. Mosquitoes had a strong tendency to endophagy both in NDELLE (73.57% and KOMBO (70.21%. Three anophelines species were identified; An. gambiae, An. funestus s.s and An. moucheti s.s.. An. gambiae and An. funestus s.s. represented the bulk of aggressive mosquitoes in NDELLE (n=10,891; 96.62%. An. gambiae was responsible for 62.6% and 77.72% of malaria transmission in KOMBO and NDELLE respectively. Mean entomological inoculation rate recorded in KOMBO and NDELLE were 4.82 and 2.02 infective bites per person per night respectively. Vector control was mainly based on the use of long-lasting insecticidal nets and indoor residual spraying. The degraded forest environment added to the presence of fishponds resulted in the increase of aggressive mosquito density but not of malaria transmission. The managers should use these data for monitoring and evaluation of the impact of their project; malaria control strategies should be included in

  12. Host choice and multiple blood feeding behaviour of malaria vectors and other anophelines in Mwea rice scheme, Kenya

    Directory of Open Access Journals (Sweden)

    Jacob Benjamin G

    2008-02-01

    Full Text Available Abstract Background Studies were conducted between April 2004 and February 2006 to determine the blood-feeding pattern of Anopheles mosquitoes in Mwea Kenya. Methods Samples were collected indoors by pyrethrum spay catch and outdoors by Centers for Disease Control light traps and processed for blood meal analysis by an Enzyme-linked Immunosorbent Assay. Results A total of 3,333 blood-fed Anopheles mosquitoes representing four Anopheles species were collected and 2,796 of the samples were assayed, with Anopheles arabiensis comprising 76.2% (n = 2,542 followed in decreasing order by Anopheles coustani 8.9% (n = 297, Anopheles pharoensis 8.2% (n = 272 and Anopheles funestus 6.7% (n = 222. All mosquito species had a high preference for bovine (range 56.3–71.4% over human (range 1.1–23.9% or goat (0.1–2.2% blood meals. Some individuals from all the four species were found to contain mixed blood meals. The bovine blood index (BBI for An. arabiensis was significantly higher for populations collected indoors (71.8%, than populations collected outdoors (41.3%, but the human blood index (HBI did not differ significantly between the two populations. In contrast, BBI for indoor collected An. funestus (51.4% was significantly lower than for outdoor collected populations (78.0% and the HBI was significantly higher indoors (28.7% than outdoors (2.4%. Anthropophily of An. funestus was lowest within the rice scheme, moderate in unplanned rice agro-ecosystem, and highest within the non-irrigated agro-ecosystem. Anthropophily of An. arabiensis was significantly higher in the non-irrigated agro-ecosystem than in the other agro-ecosystems. Conclusion These findings suggest that rice cultivation has an effect on host choice by Anopheles mosquitoes. The study further indicate that zooprophylaxis may be a potential strategy for malaria control, but there is need to assess how domestic animals may influence arboviruses epidemiology before adapting the strategy.

  13. Mosquito coil emissions and health implications.

    Science.gov (United States)

    Liu, Weili; Zhang, Junfeng; Hashim, Jamal H; Jalaludin, Juliana; Hashim, Zailina; Goldstein, Bernard D

    2003-09-01

    Burning mosquito coils indoors generates smoke that can control mosquitoes effectively. This practice is currently used in numerous households in Asia, Africa, and South America. However, the smoke may contain pollutants of health concern. We conducted the present study to characterize the emissions from four common brands of mosquito coils from China and two common brands from Malaysia. We used mass balance equations to determine emission rates of fine particles (particulate matter pollutant concentrations resulting from burning mosquito coils could substantially exceed health-based air quality standards or guidelines. Under the same combustion conditions, the tested Malaysian mosquito coils generated more measured pollutants than did the tested Chinese mosquito coils. We also identified a large suite of volatile organic compounds, including carcinogens and suspected carcinogens, in the coil smoke. In a set of experiments conducted in a room, we examined the size distribution of particulate matter contained in the coil smoke and found that the particles were ultrafine and fine. The findings from the present study suggest that exposure to the smoke of mosquito coils similar to the tested ones can pose significant acute and chronic health risks. For example, burning one mosquito coil would release the same amount of PM(2.5) mass as burning 75-137 cigarettes. The emission of formaldehyde from burning one coil can be as high as that released from burning 51 cigarettes.

  14. Free flight of the mosquito Aedes aegypti

    CERN Document Server

    Iams, S M

    2012-01-01

    High speed video observations of free flying male Aedes aegypti mosquitoes, the dengue and yellow fever vector, along with custom measurement methods, enable measurement of wingbeat frequency, body position and body orientation of mosquitoes during flight. We find these mosquitoes flap their wings at approximately 850 Hz. We also generate body yaw, body pitch and wing deviation measurements with standard deviations of less than 1 degree and find that sideways velocity and acceleration are important components of mosquito motion. Rapid turns involving changes in flight direction often involve large sideways accelerations. These do not correspond to commensurate changes in body heading, and the insect's flight direction and body heading are decoupled during flight. These findings call in to question the role of yaw control in mosquito flight. In addition, using orientation data, we find that sideways accelerations are well explained by roll-based rotation of the lift vector. In contrast, the insect's body pitch...

  15. Mosquito flight failure in heavy fog

    Science.gov (United States)

    Dickerson, Andrew; Telljohann, Luke; Thornton, Lee-Ellen; Moyer, Caitlin; Hu, David

    2012-11-01

    Mosquitoes thrive during rainfall and high humidity. We previously found that mosquitoes are successful fliers through rainfall. Heavy fog, consisting of drops three orders of magnitude smaller in mass than raindrops, presents an environment in which mosquitoes cannot maintain flight. Through high-speed videography, we observe mosquitoes reduce wingbeat frequency in heavy fog, but retain the ability to generate sufficient force to lift their bodies, even after significant dew deposition. They are unable, however, to maintain an upright position required for sustainable flight. A mosquito's primary flight control mechanism is its halteres, small knobbed structures evolved from the hind wings, which flap anti-phase with the wings and provide gyroscopic feedback through Coriolis forces. Though the halteres are hydrophobic, repeated collisions with 10-micron fog particles hinders flight control, leading to flight failure.

  16. Asymptomatic humans transmit dengue virus to mosquitoes.

    Science.gov (United States)

    Duong, Veasna; Lambrechts, Louis; Paul, Richard E; Ly, Sowath; Lay, Rath Srey; Long, Kanya C; Huy, Rekol; Tarantola, Arnaud; Scott, Thomas W; Sakuntabhai, Anavaj; Buchy, Philippe

    2015-11-24

    Three-quarters of the estimated 390 million dengue virus (DENV) infections each year are clinically inapparent. People with inapparent dengue virus infections are generally considered dead-end hosts for transmission because they do not reach sufficiently high viremia levels to infect mosquitoes. Here, we show that, despite their lower average level of viremia, asymptomatic people can be infectious to mosquitoes. Moreover, at a given level of viremia, DENV-infected people with no detectable symptoms or before the onset of symptoms are significantly more infectious to mosquitoes than people with symptomatic infections. Because DENV viremic people without clinical symptoms may be exposed to more mosquitoes through their undisrupted daily routines than sick people and represent the bulk of DENV infections, our data indicate that they have the potential to contribute significantly more to virus transmission to mosquitoes than previously recognized.

  17. Behavioral patterns, parity rate and natural infection analysis in anopheline species involved in the transmission of malaria in the northeastern Brazilian Amazon region.

    Science.gov (United States)

    Barbosa, Ledayane Mayana Costa; Souto, Raimundo Nonato Picanço; Dos Anjos Ferreira, Ricardo Marcelo; Scarpassa, Vera Margarete

    2016-12-01

    The characterization of behavioral patterns allows a better understanding of the transmission dynamics and the design of more effective malaria vector control strategies. This study analyzed the behavioral patterns of the Anopheles species of the Coração district situated in the northeast of the Brazilian Amazon region. The behavioral patterns of the anopheline species were measured based on the 36 collection sites of this district from December 2010 to November 2011. Collections of four hours for three consecutive nights each month and four 12-h collections, comprising two in the rainy season and two in the dry season, were performed. Furthermore, to infer the anthropophily and zoophily indexes, four additional four-hour collections were performed. The samples were also evaluated for parity rate and natural infectivity for Plasmodium spp. A total of 1689 anophelines were captured, comprising of nine species and two subgenera (Nyssorhynchus - six species, and Anopheles - three species). Anopheles darlingi was the most abundant and widely distributed species in the area, followed by A. braziliensis and A.marajoara. Anopheles darlingi and A. marajoara were the only species present in the four collections of 12-h, but only A. darlingi showed activity throughout night. Anopheles darlingi was the most anthropophilic species (AI=0.40), but the zoophily index was higher (ZI=0.60), revealing an eclectic and opportunistic behavior. Of the six most frequent species, A. nuneztovari s.l. was the most zoophilic species (ZI=1.00). All captured species showed predominance towards biting in outdoor environments. Anopheles darlingi and A. braziliensis showed multimodal biting peaks, whereas A. marajoara revealed a stable pattern, with the biting peak after sunset. Using the PCR technique, no anopheline was found infected with the malaria parasite. Since A. darlingi and A. marajoara are recognized as important vectors in this region, the district of Coração may be considered as

  18. Green Nanoparticles for Mosquito Control

    Science.gov (United States)

    Soni, Namita; Prakash, Soam

    2014-01-01

    Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicum or C. verum J. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM). The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs). The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito. PMID:25243210

  19. Green nanoparticles for mosquito control.

    Science.gov (United States)

    Soni, Namita; Prakash, Soam

    2014-01-01

    Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag) and gold (Au) nanoparticles (NPs) were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum) (C. zyelanicum or C. verum J. Presl). Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM). The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs). The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito.

  20. Green Nanoparticles for Mosquito Control

    Directory of Open Access Journals (Sweden)

    Namita Soni

    2014-01-01

    Full Text Available Here, we have used the green method for synthesis of silver and gold nanoparticles. In the present study the silver (Ag and gold (Au nanoparticles (NPs were synthesized by using the aqueous bark extract of Indian spice dalchini (Cinnamomum zeylanicum (C. zyelanicum or C. verum J. Presl. Additionally, we have used these synthesized nanoparticles for mosquito control. The larvicidal activity has been tested against the malaria vector Anopheles stephensi and filariasis vector Culex quinquefasciatus. The results were obtained using UV-visible spectrophotometer and the images were recorded with a transmission electron microscope (TEM. The efficacy tests were then performed at different concentrations and varying numbers of hours by probit analysis. The synthesized AgNPs were in spherical shape and average sizes (11.77 nm AgNPs and 46.48 nm AuNPs. The larvae of An. stephensi were found highly susceptible to the synthesized AgNPs and AuNPs than the Cx. quinquefasciatus. These results suggest that the C. zeylanicum synthesized silver and gold nanoparticles have the potential to be used as an ideal ecofriendly approach for the control of mosquito.

  1. INFLUENCIA DEL PROCEDIMIENTO EMPLEADO PARA DETERMINAR LA RECTA DE ECONOMÍA DE PEDALEO EN EL CÁLCULO DEL DÉFICIT MÁXIMO DE OXÍGENO ACUMULADO

    Directory of Open Access Journals (Sweden)

    J. A. López

    2010-09-01

    Full Text Available

    RESUMEN

    Para determinar la influencia que tienen en los valores de DMO, el número, intensidad y duración de las cargas submáximas utilizadas para calcular la recta de economía, 6 varones acudieron al laboratorio en 8 ocasiones. Tras la familiarización, se determinó el VO2 pico, y el el VO2 a 80, 100, 110, 120, 130, 140, 150, 160, 180, 200 y nuevamente 100 w. Se calcularon 4 rectas diferentes por regresión lineal: R1, R2, R3, R4. Las rectas R1, R2 y R4 se obtuvieron a partir de la relación VO2/intensidad, entre 80 y 130 w (R1, n=5, entre 140 y 200 w (R2, n=5 y entre 80 y 200 w (R4, n=10, tomando como valor de VO2 correspondiente a cada carga el valor medio alcanzado en los minutos 5 y 6. R3 se calculó a partir de la relación VO2/intensidad, entre 80 y 200 w en test incremental hasta el agotamiento (n=4, tomando como valor de VO2 correspondiente a cada carga el valor medio alcanzado en el 3er min. Finalmente, se calculó el déficit máximo de O2 (DMO en un test de Wingate de 45 s.

    R4 y R3 presentaron parámetros similares, que no se correlacionaron entre sí. Las pendientes fueron un 15 % inferiores en R1 que en R2 (9.591 ± 1.236 y 11.261 ± 0.878 ml.min-1, respectivamente, p<0.05, mientras la ordenada en el origen fue mayor en R1 que en R2 (709.216 ± 154.808 y 510.583 ± 114.204 ml.min-1, respectivamente, p<0.05. Entre R1 y R2 tampoco se obtuvieron correlaciones significativas ni entre pendientes, ni entre puntos de intercepción. Los valores de DMO fueron un 18 % superiores, cuando la recta de economía se obtuvo mediante cargas altas (R2 que cuando se obtuvo mediante cargas bajas (R1; p=0.06. El índice de correlación del DMO calculado con R3 y R4 no fue significativo (r=0.76, p=0.08. Sin embargo, se obtuvo una correlación muy alta entre los valores de DMO

  2. Anopheline ecology and malaria transmission during the construction of an irrigation canal in an endemic district of Odisha, India

    Directory of Open Access Journals (Sweden)

    B. K. Panigrahi

    2013-12-01

    Full Text Available Background & objectives: A new irrigation canal system is under construction in Dhenkanal district of Odisha, to increase the production of rice crop and thereby improve the living standard of farmers in the project area. Construction of canal may increase the transmission of malaria by creating vector breeding habitats. Knowledge about bionomics of vectors will support authorities for appropriate management of the disease in a changing ecological set up. The aim of this study was to assess the malaria transmission in the bank of the canal area under construction. Methods: The entomological survey was carried out in three seasons, winter, summer and rainy during the period November 2008-October 2010 in the study area. Adult mosquitoes were collected by using suction tubes and flash lights. Mosquito species identification was done by using standard keys, separated according to abdominal conditions and were kept in an isopropanol for further molecular analysis of sibling species, presence of sporozoites and human blood meal. Larvae were collected by dippers and reared in the laboratory, and the emerged adults were identified to species. The epidemiology of malaria was evaluated from the data collected by the State Health Department. Insecticide succeptibility test was done by WHO method. Results: The adult mosquito collection from the study area showed the prevalence of 14 species belonging to three genera, i.e. Anopheles, Culex and Aedes. The per man hour densities (PMHD of An. culicifacies were 3.8, 1.4, 4.8; that of An. annularis were 2.1, 1, 2.1; and that of An. fluviatilis were 1.4, 0.3, 0.6 during winter, summer and rainy seasons respectively. Sibling species identified were: An. culicifacies A, B, C and D, An. annularis A and An. fluviatilis S. Sporozoite rates of An. culicifacies A and C were 1.1 and 0.5% respectively and that of An. annularis A was 2% (reported for the first time in the state. Both the vectors (An. culicifacies and An

  3. EFFECTS OF MOSQUITO REPELLENTS ON PULMONARY FUNCTIONS

    Directory of Open Access Journals (Sweden)

    Venkatesh

    2014-08-01

    Full Text Available Mosquito bite transmits diseases like Malaria, Filaria, Dengue etc. and usage of repellents is very common and has been in use for a long time. The smoke contains Polyaromatic Hydrocarbons, Aldehydes and Ketones. Review of literature has shown ill effects of this smoke. Hence we intended to study the effect of mosquito repellents on lung functions. This study would be important to create awareness regarding usage of mosquito repellent and to adapt to non-harmful methods of preventing mosquito bites. PFT parameters FVC, FEV1, FEV1/ FVC %, FEF 25-75 and PEFR were recorded in mosquito coil users, liquidator’s users and controls that used neither. It was found that FVC and FEV1 were significantly less in coil and liquidators users compared to controls (P < 0.05. Also it was found that in both coil users and liquidator users FVC, FEV1, FEF 25 -75 and PEFR and showed progressive decline with increased duration of usage (P < 0.05. Hence it was concluded that mosquito coils and liquidators can cause progressive decline in lung functions. Alternative methods to combat mosquito menace, like personal and environmental hygiene and non-chemical methods of protection are therefore recommended.

  4. Plant extracts as potential mosquito larvicides

    Science.gov (United States)

    Ghosh, Anupam; Chowdhury, Nandita; Chandra, Goutam

    2012-01-01

    Mosquitoes act as a vector for most of the life threatening diseases like malaria, yellow fever, dengue fever, chikungunya ferver, filariasis, encephalitis, West Nile Virus infection, etc. Under the Integrated Mosquito Management (IMM), 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 non target 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 non-toxic, easily available at affordable prices, biodegradable and show broad-spectrum target-specific activities against different species of vector mosquitoes. In this article, the current state of knowledge on phytochemical sources and mosquitocidal activity, their mechanism of action on target population, variation of their larvicidal activity according to mosquito species, instar specificity, polarity of solvents used during extraction, nature of active ingredient and promising advances made in biological control of mosquitoes by plant derived secondary metabolites have been reviewed. PMID:22771587

  5. Mosquito Oviposition Behavior and Vector Control

    Directory of Open Access Journals (Sweden)

    Jonathan F. Day

    2016-11-01

    Full Text Available The burden of gene transfer from one mosquito generation to the next falls on the female and her eggs. The selection of an oviposition site that guarantees egg and larval survival is a critical step in the reproductive process. The dangers associated with ephemeral aquatic habitats, lengthy droughts, freezing winters, and the absence of larval nutrition makes careful oviposition site selection by a female mosquito extremely important. Mosquito species exhibit a remarkable diversity of oviposition behaviors that ensure eggs are deposited into microenvironments conducive for successful larval development and the emergence of the next mosquito generation. An understanding of mosquito oviposition behavior is necessary for the development of surveillance and control opportunities directed against specific disease vectors. For example, Aedes aegypti Linnaeus is the vector of viruses causing important human diseases including yellow fever, dengue, chikungunya, and Zika. The preference of this species to oviposit in natural and artificial containers has facilitated the development of Ae. aegypti-specific surveillance and toxic oviposition traps designed to detect and control this important vector species in and around disease foci. A better understanding of the wide diversity of mosquito oviposition behavior will allow the development of new and innovative surveillance and control devices directed against other important mosquito vectors of human and animal disease.

  6. Ecology of mosquitoes of Midwestern Nigeria

    Directory of Open Access Journals (Sweden)

    Godwin R.A. Okogun, Jude C. Anosike, Anthony N. Okere & Bethran E.B. Nwoke

    2005-03-01

    Full Text Available Background & objectives: The ecology and distribution of various mosquito species is important inthe determination of mosquito vector abundance and associated diseases prevalence. The distributionof various mosquito genera in natural and artificial habitats and their relative species abundancewas studied between August 2002 and July 2003 in three foci (Uromi, Ekpoma and Auchi comprisingthe Esan and Etsako regions of Midwestern Nigeria.Methods: Sampling was carried out by the method of Hopkins (1952 by dipping using a pipette orladle depending on container types. Pooled contents of smaller containers were sampled with a pondnet. All breeding sources of mosquito larvae were grouped into five (5 depending on their nature,constitution and the physiochemical properties. Artificial mosquito cultures were also carried out infour different container types; plastics, metal cans, earthenware pots and bamboo strips, in parts oftwo different macro habitats subdivided into area of high human activities (AHHA and areas ofderived/secondary vegetation (ADSV. Environmental temperatures, rainfall and relative humiditywere monitored during the study.Results: The present study revealed 17 mosquito species belonging to three genera (Anopheles,Culex and Aedes which are potential vectors of four human diseases in the areas surveyed. A total of736 mosquito larvae were encountered in artificial sources and 568 larvae were harvested from naturalsources. Pools, plastics and metal cans were the predominant artificial sources of mosquito larvae.Conclusion: The contribution of human activities and increasing environmental modification to thebreeding of human disease vector mosquitoes is of importance and selective vector control measuresincluding larviciding are recommended particularly before onset of rainy season

  7. Plasmodium-mosquito interactions, phage display libraries and transgenic mosquitoes impaired for malaria transmission.

    Science.gov (United States)

    Ghosh, A K; Moreira, L A; Jacobs-Lorena, M

    2002-10-01

    Malaria continues to kill millions of people every year and new strategies to combat this disease are urgently needed. Recent advances in the study of the mosquito vector and its interactions with the malaria parasite suggest that it may be possible to genetically manipulate the mosquito in order to reduce its vectorial capacity. Here we review the advances made to date in four areas: (1) the introduction of foreign genes into the mosquito germ line; (2) the characterization of tissue-specific promoters; (3) the identification of gene products that block development of the parasite in the mosquito; and (4) the generation of transgenic mosquitoes impaired for malaria transmission. While initial results show great promise, the problem of how to spread the blocking genes through wild mosquito populations remains to be solved.

  8. Laboratory observations on the larvicidal efficacy of three plant species against mosquito vectors of malaria, dengue/dengue hemorrhagic fever (DF/DHF) and lymphatic filariasis in the semi-arid desert.

    Science.gov (United States)

    Bansal, S K; Singh, Karam V; Sharma, Sapna; Sherwani, M R K

    2012-05-01

    Comparative larvicidal efficacy of aqueous and organic solvent extracts from seeds, leaves and flowers of three desert plants viz. Calotropis procera (Aiton), Tephrosia purpurea (L.) Pers. and Prosopis juliflora (Sw.) DC. was evaluated against Anopheles stephensi (Liston), Aedes aegypti (Linnaeus) and Culex quinquefasciatus (Say). For this purpose larvae of all the three mosquito species were reared in the laboratory and studies carried out on late 3rd or early 4th instars using standard WHO technique. Based on concentration mortality data 24 and 48 hr LC50and LC90 values along with their 95% fiducial limits, regression equation, chi-square (chi2)/ heterogeneity of the response were determined by log probit regression analysis. Experiments were carried out with different solvent extracts of seeds of C. procera which revealed that methanol (24 hr LC50: 127.2, 194.8, 361.0) and acetone (229.9, 368.1,193.0 mg l(-1)) extracts were more effective with the three mosquito species, respectively. Petroleum ether extract was effective only on An. stephensi while aqueous extracts were not effective at all with any of the mosquito species (mortality purpurea and leaves of P. juliflora were 74.9, 63.2 and 47.0 and 96.2,128.1 and 118.8 mg l(-1) for the above three mosquito species, respectively. Experiments carried out up to 500 mg l-(1) with leaves (T. purpurea) and seeds (P. juliflora) extracts show only up to 10-30% mortality indicating that active larvicidal principle may be present only in the seeds of Tephrosia and leaves of Prosopis. In general, anophelines were found more susceptible than the culicines to the plant derived derivatives. More studies are being carried outon some other desert plants found in this arid region. The study would be of great importance while formulating vector control strategy based on alternative plant based insecticides in this semi-arid region.

  9. Can mosquitoes fly in the rain?

    CERN Document Server

    Dickerson, Andrew; Madhavan, Nihar; Hu, David

    2011-01-01

    Collisions with raindrops are one of many obstacles insects face during flight. In this fluid dynamics video, we present a series of high-speed films of impacts between mosquitoes and raindrops. We also present drop impacts upon insect mimics, which are unsupported styrofoam balls of the same mass as mosquitoes. High-speed videography and particle tracking during collision are employed to determine the insect position versus time. We determine the magnitude of acceleration by considering the momentum transfer and impact duration. Experiments with live mosquitoes indicate a surprising ability to quickly recover flight post-collision, despite accelerations of 30-300 gravities over durations of 1 ms.

  10. Mosquito transgenic technologies to reduce Plasmodium transmission.

    Science.gov (United States)

    Fuchs, Silke; Nolan, Tony; Crisanti, Andrea

    2013-01-01

    The ability to introduce genetic constructs of choice into the genome of Anopheles mosquitoes provides a valuable tool to study the molecular interactions between the Plasmodium parasite and its insect host. In the long term, this technology could potentially offer new ways to control vector-borne diseases through the suppression of target mosquito populations or through the introgression of traits that preclude pathogen transmission. Here, we describe in detail protocols for the generation of transgenic Anopheles gambiae mosquitoes based on germ-line transformation using either modified transposable elements or the site-specific PhiC31 recombinase.

  11. A possible alternative method for collecting mosquito larvae in rice fields

    Directory of Open Access Journals (Sweden)

    Goff Gilbert

    2002-04-01

    Full Text Available Abstract Background Rice fields are efficient breeding places for malaria vectors in Madagascar. In order to establish as easily as possible if a rice field is an effective larval site for anophelines, we compared classical dipping versus a net as methods of collecting larvae. Results Using similar collecting procedures, we found that the total number of anopheline larvae collected with the net was exactly double (174/87 that collected by dipping. The number of anopheline species collected was also greater with a net. Conclusions The net is an effective means of collecting anopheline larvae and can be used for qualitative ecological studies and to rapidly determine which rice fields are containing malaria vectors.

  12. The Impact of Transgenic Mosquitoes on Dengue Virulence to Humans and Mosquitoes

    OpenAIRE

    Medlock, Jan; Luz, Paula M; Struchiner,Claudio J.; Galvani, Alison P.

    2009-01-01

    Dengue is a major public health concern in the tropics and subtropics. Innovative transgenic strategies to render Aedes aegypti mosquitoes, the primary vector of dengue, incompetent for dengue transmission are under development. We modeled the evolutionary impact of different transgenic mosquito strategies on dengue-induced mortality, that is, dengue virulence, to both humans and mosquitoes. This model incorporates various evolutionary trade-offs in dengue virus epidemiological traits, for ex...

  13. Efficacy and efficiency of new Bacillus thuringiensis var israelensis and Bacillus sphaericus formulations against Afrotropical anophelines in Western Kenya.

    Science.gov (United States)

    Fillinger, Ulrike; Knols, Bart G J; Becker, Norbert

    2003-01-01

    We evaluated the efficacy of new water-dispersible granular (WDG) formulations of Bacillus thuringienis var. israelensis (Bti; VectoBac) and B. sphaericus (Bs; VectoLex), Valent BioScience Corp., Illinois, USA) for the control of larval Anopheles gambiae sensu lato Giles mosquitoes in a malaria-endemic area around Lake Victoria, Western Kenya. WDG and powder formulations were compared in laboratory bioassays and followed by efficiency and residual effect assessments of both WDG formulations in open field experiments. LC50 and LC95 values for the Bti/Bs strains and their formulations show high susceptibility of A. gambiae sensu stricto under laboratory conditions. The larvae proved more susceptible to Bs than to Bti and the WDG formulations were slightly superior to the powder formulations. High efficiency was also shown in the open field trials, and a minimum dosage of 200 g/ha Bti WDG, representing the LC95 of the laboratory tests, was sufficient to fully suppress emergence of mosquitoes when applied at weekly intervals. Bti WDG did not show a residual effect, irrespective of the concentration applied. The Bs WDG formulation, however, showed significant larval reductions up to 11 days post-treatment at application doses of either 1 or 5 kg/ha. We conclude that the main malaria vector in our study area is highly susceptible to these microbial control agents. Minimum effective dosages to achieve elimination of the larval population in a given habitat are extremely low and environmental impact is negligible. Microbial products for larval control have therefore great potential within Integrated Vector Management programmes and may augment control efforts against adult vector stages, such as the use of insecticide-treated bednets, in many parts of Africa.

  14. Scientists Create Mosquitoes Resistant to Dengue Virus

    Science.gov (United States)

    ... to the dengue virus, which might eventually help control the spread of the disease in humans. The team at Johns Hopkins Bloomberg School of Public Health in Baltimore genetically modified Aedes aegypti mosquitoes to boost their natural ability to fight ...

  15. Slow Death by Many Mosquito Bites

    CERN Document Server

    Redner, S

    2014-01-01

    We study the dynamics of a single diffusing particle (a "man") with diffusivity $D_M$ that is attacked by another diffusing particle (a "mosquito") with fixed diffusivity $D_m$. Each time the mosquito meets and bites the man, the diffusivity of the man is reduced by a fixed amount, while the diffusivity of the mosquito is unchanged. The mosquito is also displaced by a small distance $\\pm a$ with respect to the man after each encounter. The man is defined as dead when $D_M$ reaches zero. At the moment when the man dies, his probability distribution of displacements $x$ is given by a Cauchy form, which asymptotically decays as $x^{-2}$, while the distribution of times $t$ when the man dies asymptotically decays as $t^{-3/2}$, which has the same form as the one-dimensional first-passage probability.

  16. Mosquito, adult feeding on the skin (image)

    Science.gov (United States)

    There are many different species of mosquito, which can carry some of the world's most common and significant infectious diseases, including West Nile, Malaria, yellow fever, viral encephalitis, and ...

  17. Vector Competence of Mosquitoes for Arboviruses

    Science.gov (United States)

    1989-07-30

    ml) on the titers of three alphaviruses , Sindbis(A), western equine encephalomyelitis (B), Venezuelan equine encephalomyelitis (C), and the...population have been delineated and discussed with reference to the mosquito, Culex tarsalis, and the alphavirus , western equine encephalomyelitis (WEE...mechanism that appears to control WEE viral replication (Hardy et al., 1983; Kramer et al., 1989; Ann. Prog. Rpt., 1988). The ability of a mosquito to

  18. Vorticella sp: Prospective Mosquito Biocontrol Agent

    OpenAIRE

    Patil, Chandrashekhar Devidas; Narkhede, Chandrakant Prakash; Suryawanshi, Rahul Khushal; Patil, Satish Vitthal

    2016-01-01

    Background: Considering the disadvantages of chemical insecticides, we aimed to evaluate Vorticella parasites for control of mosquito larvae of Anopheles stephensi and Aedes aegypti at different larval stages. Methods: Vorticella sp infected mosquito larvae were crushed in the 0.85% saline and homogenized well to get Vorticella in suspension. The effects of Vorticella sp infections on larval development were investigated by inoculating protozoan on different larval instars of An. stephensi an...

  19. Vorticella sp: Prospective Mosquito Biocontrol agent

    OpenAIRE

    Chandrashekhar Devidas Patil; Chandrakant Prakash Narkhede; Rahul Khushal Suryawanshi; Satish Vitthal Patil

    2016-01-01

    Background: Considering the disadvantages of chemical insecticides, we aimed to evaluate Vorticella parasites for control of mosquito larvae of Anopheles stephensi and Aedes aegypti at different larval stages.Methods: Vorticella sp infected mosquito larvae were crushed in the 0.85% saline and homogenized well to get Vorti­cella in suspension. The effects of Vorticella sp infections on larval development were investigated by inoculat­ing protozoan on different larval instars of An. stephensi a...

  20. Modelling and analysis of impulsive releases of sterile mosquitoes.

    Science.gov (United States)

    Huang, Mingzhan; Song, Xinyu; Li, Jia

    2017-12-01

    To study the impact of releasing sterile mosquitoes on mosquito-borne disease transmissions, we propose two mathematical models with impulsive releases of sterile mosquitoes. We consider periodic impulsive releases in the first model and obtain the existence, uniqueness, and globally stability of a wild-mosquito-eradication periodic solution. We also establish thresholds for the control of the wild mosquito population by selecting the release rate and the release period. In the second model, the impulsive releases are determined by the closely monitored wild mosquito density, or the state feedback. We prove the existence of an order one periodic solution and find a relatively small attraction region, which ensures the wild mosquito population is under control. We provide numerical analysis which shows that a smaller release rate and more frequent releases are more efficient in controlling the wild mosquito population for the periodic releases, but an early release of sterile mosquitoes is more effective for the state feedback releases.

  1. Chikungunya virus and its mosquito vectors.

    Science.gov (United States)

    Higgs, Stephen; Vanlandingham, Dana

    2015-04-01

    Chikungunya virus (CHIKV), a mosquito-borne alphavirus of increasing public health significance, has caused large epidemics in Africa and the Indian Ocean basin; now it is spreading throughout the Americas. The primary vectors of CHIKV are Aedes (Ae.) aegypti and, after the introduction of a mutation in the E1 envelope protein gene, the highly anthropophilic and geographically widespread Ae. albopictus mosquito. We review here research efforts to characterize the viral genetic basis of mosquito-vector interactions, the use of RNA interference and other strategies for the control of CHIKV in mosquitoes, and the potentiation of CHIKV infection by mosquito saliva. Over the past decade, CHIKV has emerged on a truly global scale. Since 2013, CHIKV transmission has been reported throughout the Caribbean region, in North America, and in Central and South American countries, including Brazil, Columbia, Costa Rica, El Salvador, French Guiana, Guatemala, Guyana, Nicaragua, Panama, Suriname, and Venezuela. Closing the gaps in our knowledge of driving factors behind the rapid geographic expansion of CHIKV should be considered a research priority. The abundance of multiple primate species in many of these countries, together with species of mosquito that have never been exposed to CHIKV, may provide opportunities for this highly adaptable virus to establish sylvatic cycles that to date have not been seen outside of Africa. The short-term and long-term ecological consequences of such transmission cycles, including the impact on wildlife and people living in these areas, are completely unknown.

  2. Research Contributing to Improvements in Controlling Florida’s Mosquitoes and Mosquito-borne Diseases

    Directory of Open Access Journals (Sweden)

    Walter J. Tabachnick

    2016-09-01

    Full Text Available Research on mosquitoes and mosquito-borne diseases has contributed to improvements in providing effective, efficient, and environmentally proper mosquito control. Florida has benefitted from several research accomplishments that have increased the state’s mosquito control capabilities. Research with Florida’s mosquitoes has resulted in the development of ecologically sound management of mosquito impoundments on Florida’s east coast. This strategy, called Rotational Impoundment Management (RIM, has improved the ability to target the delivery of pesticides and has helped to reduce non-target effects and environmental damage. Research has led to the development of an arbovirus surveillance system which includes sentinel chicken surveillance, real time use of environmental contributing factors like meteorology and hydrology to target mosquito control, as well as public health efforts to mitigate disease outbreaks to areas with risk of disease. These research driven improvements have provided substantial benefits to all of Florida. More research is needed to meet the future challenges to reduce emerging pathogens like Zika virus and the consequences of environmental changes like global climate change that are likely to influence the effects of mosquito-borne pathogens on human health and well-being.

  3. Research Contributing to Improvements in Controlling Florida’s Mosquitoes and Mosquito-Borne Diseases

    Science.gov (United States)

    Tabachnick, Walter J.

    2016-01-01

    Research on mosquitoes and mosquito-borne diseases has contributed to improvements in providing effective, efficient, and environmentally proper mosquito control. Florida has benefitted from several research accomplishments that have increased the state’s mosquito control capabilities. Research with Florida’s mosquitoes has resulted in the development of ecologically sound management of mosquito impoundments on Florida’s east coast. This strategy, called Rotational Impoundment Management (RIM), has improved the ability to target the delivery of pesticides and has helped to reduce non-target effects and environmental damage. Research has led to the development of an arbovirus surveillance system which includes sentinel chicken surveillance, real time use of environmental contributing factors like meteorology and hydrology to target mosquito control, as well as public health efforts to mitigate disease outbreaks to areas with risk of disease. These research driven improvements have provided substantial benefits to all of Florida. More research is needed to meet the future challenges to reduce emerging pathogens like Zika virus and the consequences of environmental changes like global climate change that are likely to influence the effects of mosquito-borne pathogens on human health and well-being. PMID:27690112

  4. Controle los mosquitos que están en el exterior (Controlling Mosquitoes Outside)

    Centers for Disease Control (CDC) Podcasts

    2016-07-11

    Los mosquitos pueden transmitir virus como el del zika. En este podcast, el Sr. Francisco le enseñará a usted y a su vecina Adriana diferentes maneras para ayudar a reducir la cantidad de mosquitos fuera de su casa. Los consejos incluyen eliminar áreas de agua estancada donde los mosquitos ponen sus huevos, usar larvicidas para matar mosquitos jóvenes, y reparar grietas y cubrir las ventilaciones de los pozos sépticos. También aprenderá cómo se usan los aviones que ayudan a rociar insecticida para los mosquitos.  Created: 7/11/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 7/11/2016.

  5. Engineered mosquitoes to fight mosquito borne diseases: not a merely technical issue.

    Science.gov (United States)

    Favia, Guido

    2015-01-01

    Malaria, dengue and other mosquito-borne diseases pose dramatic problems of public health, particularly in tropical and sub-tropical countries. Historically, vector control has been one of the most successfully strategies to eradicate some mosquito-borne diseases, as witnessed by malaria eradication in Mediterranean regions such as Italy and Greece. Vector control through insecticides has been used worldwide; unfortunately, it is losing effectiveness due to spread of resistances. Control of mosquito-borne diseases through field-releases of genetically engineered mosquitoes is an innovative and now feasible approach. Genetically modified mosquitoes have already been released into the wild in some regions, and protocols for this release are on hand in others. Local authorities are vigilant that transgenic insects in the field are safe for human and animal populations, and the public engagement in every control program is assuming a central role.

  6. Mayaro virus isolated from a Trinidadian mosquito, Mansonia venezuelensis.

    Science.gov (United States)

    AITKEN, T H; DOWNS, W G; ANDERSON, C R; SPENCE, L; CASALS, J

    1960-04-01

    A strain of Mayaro virus has been isolated in Trinidad from the mosquito Mansonia venezuelensis. This is the first record of isolation of this agent from naturally infected mosquitoes, caught in the wild.

  7. 3 Zika-Carrying Mosquitoes Found in Florida

    Science.gov (United States)

    ... infection have occurred, officials said. Ninety-five additional mosquito samples were subsequently tested for Zika and those ... best in the nation when it comes to mosquito surveillance and control, and this detection enables us ...

  8. Just Spraying Adult Mosquitoes Won't Curb Zika

    Science.gov (United States)

    ... html Just Spraying Adult Mosquitoes Won't Curb Zika: Study Lab work suggests larvicide also needed to ... 2016 (HealthDay News) -- Female mosquitoes can transmit the Zika virus to their eggs and offspring, and this ...

  9. Vorticella sp: Prospective Mosquito Biocontrol agent

    Directory of Open Access Journals (Sweden)

    Chandrashekhar Devidas Patil

    2016-10-01

    Full Text Available Background: Considering the disadvantages of chemical insecticides, we aimed to evaluate Vorticella parasites for control of mosquito larvae of Anopheles stephensi and Aedes aegypti at different larval stages.Methods: Vorticella sp infected mosquito larvae were crushed in the 0.85% saline and homogenized well to get Vorti­cella in suspension. The effects of Vorticella sp infections on larval development were investigated by inoculat­ing protozoan on different larval instars of An. stephensi and Ae. aegypti and observed under light microscope. Le­thal time of the Vorticella infected larvae at different stages was calculated.Results: First and 2nd larval instars of both An. stephensi and Ae. aegypti did not show signs of infection by Vorti­cella sp., whereas 3rd instars of An. stephensi showed more Vorticella infection than those of Ae. aegypti. However, 4th larval instars of both mosquitoes were heavily infected with Vorticella parasite which was responsible for slug­gish movements of larvae and eventually death. Moreover, parasites (Vorticella spp were responsible for more than 90% reduction in adult emergence for both infected An. stephensi and Ae. aegypti.Conclusion: This study provides insights for mosquito larvicidal action of surface parasite Vorticella on different larval stages of An. stephensi and Ae. Aegypti. It could be suggested as a potential candidate in mosquito biocontrol programs.

  10. Current Status of Deltabaculoviruses, Cypoviruses and Chloriridoviruses Pathogenic for Mosquitoes

    Institute of Scientific and Technical Information of China (English)

    James J. Becnel

    2007-01-01

    There are a variety of viral pathogens that cause disease in mosquitoes with most belonging to three major groups. The most common viruses of mosquitoes are the baculoviruses (DBVs) (Baculoviridae: Deltabaculovirus), cytoplasmic polyhedrosis viruses (CPVs) (Reoviridae: Cypovirus) and the iridoviruses (MIVs) (Iridoviridae: Chloriridovirus). Baculoviruses and iridoviruses are DNA viruses while cypoviruses are the main RNA viruses in mosquitoes. This review presents an overview of the current status and recent advancements in understanding the biology and molecular features of mosquito pathogenic viruses.

  11. Thule AB, Greenland, Mosquito Survey and Arbovirus Surveillance, 2012

    Science.gov (United States)

    2013-11-21

    NUMBER 5f. WORK UNIT NUMBER 7. PERFORMING ORGANIZATION NAME(S) AND ADDRESS(ES) USAF School of Aerospace Medicine Public Health and Preventive ...July 2012. One species of mosquitoes, Aedes impiger, was collected and more than 3000 were processed for virus testing. Active mosquito breeding...of mosquitoes, Aedes impiger, was collected and more than 3000 were processed for virus testing. Active mosquito breeding sites were located

  12. Zika Virus Vector Competency of Mosquitoes, Gulf Coast, United States

    Science.gov (United States)

    Hart, Charles E.; Roundy, Christopher M.; Azar, Sasha R.; Huang, Jing H.; Yun, Ruimei; Reynolds, Erin; Leal, Grace; Nava, Martin R.; Vela, Jeremy; Stark, Pamela M.; Debboun, Mustapha; Rossi, Shannan; Vasilakis, Nikos

    2017-01-01

    Zika virus has recently spread throughout the Americas. Although Aedes aegypti mosquitoes are considered the primary vector, Culex quinquefasciatus and mosquitoes of other species may also be vectors. We tested Cx. quinquefasciatus and Ae. taeniorhynchus mosquitoes from the US Gulf Coast; both were refractory to infection and incapable of transmission. PMID:28005002

  13. Zika Virus Vector Competency of Mosquitoes, Gulf Coast, United States.

    Science.gov (United States)

    Hart, Charles E; Roundy, Christopher M; Azar, Sasha R; Huang, Jing H; Yun, Ruimei; Reynolds, Erin; Leal, Grace; Nava, Martin R; Vela, Jeremy; Stark, Pamela M; Debboun, Mustapha; Rossi, Shannan; Vasilakis, Nikos; Thangamani, Saravanan; Weaver, Scott C

    2017-03-01

    Zika virus has recently spread throughout the Americas. Although Aedes aegypti mosquitoes are considered the primary vector, Culex quinquefasciatus and mosquitoes of other species may also be vectors. We tested Cx. quinquefasciatus and Ae. taeniorhynchus mosquitoes from the US Gulf Coast; both were refractory to infection and incapable of transmission.

  14. Evaluation of botanicals as repellents against mosquitoes.

    Science.gov (United States)

    Das, N G; Baruah, I; Talukdar, P K; Das, S C

    2003-01-01

    Repellent properties of three plant extracts--essential oil (steam distillate) of Zanthoxylum limonella (fruits), Citrus aurantifolia (leaf) and petroleum ether extract of Z. limonella (fruits) were evaluated as repellent against Aedes (S.) albopictus mosquitoes in mustard (Dhara) and coconut (Parachute) oil base under laboratory conditions. Three concentrations--10, 20 and 30% of the repellents were evaluated. Repellents in mustard oil afforded longer protection time against the bites of Aedes (S.) albopictus mosquitoes than those in coconut oil. At 30% concentration, 296-304 min protection time was achieved by the test repellents in mustard oil base while repellents in coconut oil exhibited 223.5-245 min protection time at the same concentration. Oil of Z. limonella gave the highest protection time against the bites of Aedes (S.) albopictus mosquitoes at all the concentrations than other herbal repellents tested both in mustard and coconut oil.

  15. Evaluation of botanicals as repellents against mosquitoes

    Directory of Open Access Journals (Sweden)

    N.G. Das, I. Baruah, P.K. Talukdar & S.C. Das

    2003-03-01

    Full Text Available Repellent properties of three plant extracts—essential oil (steam distillate of Zanthoxylumlimonella (fruits, Citrus aurantifolia (leaf and petroleum ether extract of Z. limonella (fruitswere evaluated as repellent against Aedes (S. albopictus mosquitoes in mustard (Dhara and coconut(Parachute oil base under laboratory conditions. Three concentrations—10, 20 and 30% of therepellents were evaluated. Repellents in mustard oil afforded longer protection time against thebites of Aedes (S. albopictus mosquitoes than those in coconut oil. At 30% concentration, 296–304 min protection time was achieved by the test repellents in mustard oil base while repellents incoconut oil exhibited 223.5–245 min protection time at the same concentration. Oil of Z. limonellagave the highest protection time against the bites of Aedes (S. albopictus mosquitoes at all theconcentrations than other herbal repellents tested both in mustard and coconut oil.

  16. Mosquitoes of Istria, a contribution to the knowledge of Croatian mosquito fauna (Diptera, Culicidae)

    OpenAIRE

    MERDIĆ, Enrih; BOCA, IVANA; SUDARIĆ BOGOJEVIĆ, MIRTA; LANDEKA, Nediljko

    2008-01-01

    Background and Purpose: Although Istria was endemic of malaria up to the mid 20th century, the mosquito fauna was studied in detail. Our investigation of mosquitoes in Istria, a very specific region with a highly diverse breeding site types, was conducted in order to gain insights into the mosquito fauna and abundance, as well as to establish the possible presence of new species. Material and Methods: The sampling took place from May to September over a seven-year period, from 1999 to ...

  17. Genetically Modified (GM) Mosquito Use to Reduce Mosquito-Transmitted Disease in the US: A Community Opinion Survey

    Science.gov (United States)

    Adalja, Amesh; Sell, Tara Kirk; McGinty, Meghan; Boddie, Crystal

    2016-01-01

    Introduction: Mosquito-borne infectious diseases such as dengue, chikungunya, and now Zika, pose a public health threat to the US, particularly Florida, the Gulf Coast states, and Hawaii. Recent autochthonous transmission of dengue and chikungunya in Florida, the recent dengue outbreak in Hawaii, and the potential for future local spread of Zika in the US, has led to the consideration of novel approaches to mosquito management. One such novel approach, the release of sterile genetically modified mosquitoes, has been proposed as a possible intervention, and a trial release of GM mosquitoes is being considered in one Florida community. However, this proposal has been controversial. The objective of this research was to increase understanding of community knowledge, attitudes, and beliefs regarding mosquito control and GM mosquitoes.   Methods: An 18-question self-administered survey was mailed to all households in the identified Key West, Florida neighborhood where a GM mosquito trial has been proposed. This survey was fielded between July 20, 2015 and November 1, 2015. The main outcome variable was opposition to the use of GM mosquitoes. Measures included demographic information and opinions on mosquitoes, mosquito control, and vector-borne diseases.   Results: A majority of survey respondents did not support use of GM mosquitoes as a mosquito control method. Discussion: Reasons for opposition included general fears about possible harmful impacts of this intervention, specific worries about human and animal health impacts from the GM mosquitoes, and environmental concerns about potential negative effects on the ecosystem. Residents were more likely to oppose GM mosquito use if they had a low perception of the potential risks posed by diseases like dengue and chikungunya, if they were female, and if they were less concerned about the need to control mosquitoes in general. These findings suggest a need for new approaches to risk communication, including

  18. Mosquito infection responses to developing filarial worms.

    Directory of Open Access Journals (Sweden)

    Sara M Erickson

    Full Text Available Human lymphatic filariasis is a mosquito-vectored disease caused by the nematode parasites Wuchereria bancrofti, Brugia malayi and Brugia timori. These are relatively large roundworms that can cause considerable damage in compatible mosquito vectors. In order to assess how mosquitoes respond to infection in compatible mosquito-filarial worm associations, microarray analysis was used to evaluate transcriptome changes in Aedes aegypti at various times during B. malayi development. Changes in transcript abundance in response to the different stages of B. malayi infection were diverse. At the early stages of midgut and thoracic muscle cell penetration, a greater number of genes were repressed compared to those that were induced (20 vs. 8. The non-feeding, intracellular first-stage larvae elicited few differences, with 4 transcripts showing an increased and 9 a decreased abundance relative to controls. Several cecropin transcripts increased in abundance after parasites molted to second-stage larvae. However, the greatest number of transcripts changed in abundance after larvae molted to third-stage larvae and migrated to the head and proboscis (120 induced, 38 repressed, including a large number of putative, immunity-related genes (approximately 13% of genes with predicted functions. To test whether the innate immune system of mosquitoes was capable of modulating permissiveness to the parasite, we activated the Toll and Imd pathway controlled rel family transcription factors Rel1 and Rel2 (by RNA interference knockdown of the pathway's negative regulators Cactus and Caspar during the early stages of infection with B. malayi. The activation of either of these immune signaling pathways, or knockdown of the Toll pathway, did not affect B. malayi in Ae. aegypti. The possibility of LF parasites evading mosquito immune responses during successful development is discussed.

  19. Evaluation of attractive toxic sugar bait (ATSB)—barrier for control of vector and nuisance mosquitoes and its effect on non-target organisms in sub-tropical environments in Florida

    Science.gov (United States)

    Qualls, Whitney A.; Müller, Günter C.; Revay, Edita E.; Allan, Sandra A.; Arheart, Kristopher L.; Beier, John C.; Smith, Michal L.; Scott, Jodi M.; Kravchenko, Vasiliy D.; Hausmann, Axel; Yefremova, Zoya A.; Xue, Rui-De

    2014-01-01

    The efficacy of attractive toxic sugar baits (ATSB) with the active ingredient eugenol, an Environmental Protection Agency exempt compound, was evaluated against vector and nuisance mosquitoes in both laboratory and field studies. In the laboratory, eugenol combined in attractive sugar bait (ASB) solution provided high levels of mortality for Aedes aegypti, Culex quinquefasciatus, and Anopheles quadrimaculatus. Field studies demonstrated significant control: > 70% reduction for Aedes atlanticus, Ae. infirmatus, and Culex nigripalpus and > 50% reduction for An. crucians, Uranotaenia sapphirina, Culiseta melanura, and Cx. erraticus three weeks post ATSB application. Furthermore, non-target feeding of six insect orders, Hymenoptera, Lepidoptera, Coleoptera, Diptera, Hemiptera, and Orthoptera, was evaluated in the field after application of a dyed-ASB to flowering and non-flowering vegetation. ASB feeding (staining) was determined by dissecting the guts and searching for food dye with a dissecting microscope. The potential impact of ATSB on non-targets, applied on green non-flowering vegetation was low for all non-target groups (0.9%). However, application of the ASB to flowering vegetation resulted in significant staining of the non-target insect orders. This highlights the need for application guidelines to reduce non-target effects. No mortality was observed in laboratory studies with predatory non-targets, spiders, praying mantis, or ground beetles, after feeding for three days on mosquitoes engorged on ATSB. Overall, our laboratory and field studies support the use of eugenol as an active ingredient for controlling important vector and nuisance mosquitoes when used as an ATSB toxin. This is the first study demonstrating effective control of anophelines in non-arid environments which suggest that even in highly competitive sugar rich environments this method could be used for control of malaria in Latin American countries. PMID:24361724

  20. Evaluation of attractive toxic sugar bait (ATSB)-Barrier for control of vector and nuisance mosquitoes and its effect on non-target organisms in sub-tropical environments in Florida.

    Science.gov (United States)

    Qualls, Whitney A; Müller, Günter C; Revay, Edita E; Allan, Sandra A; Arheart, Kristopher L; Beier, John C; Smith, Michal L; Scott, Jodi M; Kravchenko, Vasiliy D; Hausmann, Axel; Yefremova, Zoya A; Xue, Rui-De

    2014-03-01

    The efficacy of attractive toxic sugar baits (ATSB) with the active ingredient eugenol, an Environmental Protection Agency exempt compound, was evaluated against vector and nuisance mosquitoes in both laboratory and field studies. In the laboratory, eugenol combined in attractive sugar bait (ASB) solution provided high levels of mortality for Aedes aegypti, Culex quinquefasciatus, and Anopheles quadrimaculatus. Field studies demonstrated significant control: >70% reduction for Aedes atlanticus, Aedes. infirmatus, and Culex nigripalpus and >50% reduction for Anopheles crucians, Uranotaenia sapphirina, Culiseta melanura, and Culex erraticus three weeks post ATSB application. Furthermore, non-target feeding of six insect orders, Hymenoptera, Lepidoptera, Coleoptera, Diptera, Hemiptera, and Orthoptera, was evaluated in the field after application of a dyed-ASB to flowering and non-flowering vegetation. ASB feeding (staining) was determined by dissecting the guts and searching for food dye with a dissecting microscope. The potential impact of ATSB on non-targets, applied on green non-flowering vegetation was low for all non-target groups (0.9%). However, application of the ASB to flowering vegetation resulted in significant staining of the non-target insect orders. This highlights the need for application guidelines to reduce non-target effects. No mortality was observed in laboratory studies with predatory non-targets, spiders, praying mantis, or ground beetles, after feeding for three days on mosquitoes engorged on ATSB. Overall, our laboratory and field studies support the use of eugenol as an active ingredient for controlling important vector and nuisance mosquitoes when used as an ATSB toxin. This is the first study demonstrating effective control of anophelines in non-arid environments which suggest that even in highly competitive sugar rich environments this method could be used for control of malaria in Latin American countries.

  1. New classification of natural breeding habitats for Neotropical anophelines in the Yanomami Indian Reserve, Amazon Region, Brazil and a new larval sampling methodology.

    Science.gov (United States)

    Sánchez-Ribas, Jordi; Oliveira-Ferreira, Joseli; Rosa-Freitas, Maria Goreti; Trilla, Lluís; Silva-do-Nascimento, Teresa Fernandes

    2015-09-01

    Here we present the first in a series of articles about the ecology of immature stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat classification and a new larval sampling methodology. We also report some preliminary results illustrating the applicability of the methodology based on data collected in the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami communities, Parafuri and Toototobi. In these areas, we mapped and classified 112 natural breeding habitats located in low-order river systems based on their association with river flood pulses, seasonality and exposure to sun. Our classification rendered seven types of larval habitats: lakes associated with the river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas associated with the river, flooded areas not associated with the river, rainfall pools, small forest streams, medium forest streams and rivers. The methodology for larval sampling was based on the accurate quantification of the effective breeding area, taking into account the area of the perimeter and subtypes of microenvironments present per larval habitat type using a laser range finder and a small portable inflatable boat. The new classification and new sampling methodology proposed herein may be useful in vector control programs.

  2. New classification of natural breeding habitats for Neotropical anophelines in the Yanomami Indian Reserve, Amazon Region, Brazil and a new larval sampling methodology

    Directory of Open Access Journals (Sweden)

    Jordi Sánchez-Ribas

    2015-09-01

    Full Text Available Here we present the first in a series of articles about the ecology of immature stages of anophelines in the Brazilian Yanomami area. We propose a new larval habitat classification and a new larval sampling methodology. We also report some preliminary results illustrating the applicability of the methodology based on data collected in the Brazilian Amazon rainforest in a longitudinal study of two remote Yanomami communities, Parafuri and Toototobi. In these areas, we mapped and classified 112 natural breeding habitats located in low-order river systems based on their association with river flood pulses, seasonality and exposure to sun. Our classification rendered seven types of larval habitats: lakes associated with the river, which are subdivided into oxbow lakes and nonoxbow lakes, flooded areas associated with the river, flooded areas not associated with the river, rainfall pools, small forest streams, medium forest streams and rivers. The methodology for larval sampling was based on the accurate quantification of the effective breeding area, taking into account the area of the perimeter and subtypes of microenvironments present per larval habitat type using a laser range finder and a small portable inflatable boat. The new classification and new sampling methodology proposed herein may be useful in vector control programs.

  3. Cómo controlar los mosquitos en interiores (Controlling Mosquitoes Indoors)

    Centers for Disease Control (CDC) Podcasts

    2016-08-23

    Los mosquitos pueden portar virus como el del Nilo Occidental o del Zika. En este podcast, Don Francisco le muestra a sus vecinos formas en las que pueden reducir el número de mosquitos dentro de su casa.  Created: 8/23/2016 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 8/23/2016.

  4. Water management for controlling the breeding of Anopheles mosquitoes in rice irrigation schemes in Kenya.

    Science.gov (United States)

    Mutero, C M; Blank, H; Konradsen, F; van der Hoek, W

    2000-10-02

    An experiment to assess the impact of intermittent irrigation on Anopheles larval populations, rice yields and water use was conducted in the Mwea rice irrigation scheme in Kenya. Four water regimes including intermittent irrigation were tested in a complete randomized block experimental design. Intermittent irrigation was carried out on a weekly schedule, with flooded conditions from Saturday through Tuesday morning. Larval sampling at each plot was conducted every Monday and prior to draining of intermittently irrigated subplots on Tuesday. All the adult anopheline mosquitoes emerging from larvae collected in the experimental plots were identified as being An. arabiensis. By far the highest numbers of An. arabiensis 1st instar larvae were found in the intermittently irrigated subplots, indicating that the water regime provided the most attractive environment for egg laying. However, the ratio between the 4th and 1st instar larvae in the subplots was only 0.08, indicating very low survival rates. In contrast, the 4th/1st instar ratio for subplots with other water management regimes ranged between 0.27 and 0.68, suggesting a correspondingly higher survival than observed with intermittent irrigation. The total number of 4th instars was almost the same in the intermittently irrigated subplots and the irrigation system normally practised by the farmers. The failure to eliminate larval development up to the 4th instar in the former method was attributed to residual pools of water. Larval abundance fluctuated throughout the 12-week sampling period. The highest larval densities were recorded in the 3 weeks after transplanting the rice seedlings. Afterwards, larval numbers dropped dramatically as the height of rice plants increased. Rice yields at harvest did not show statistically significant differences among subplots with different water regimes. The average yield per hectare ranged from 4.8-5.3 metric tonnes. The average daily water percolation/seepage rate was 3.6 mm

  5. Species interactions among larval mosquitoes: context dependence across habitat gradients.

    Science.gov (United States)

    Juliano, Steven A

    2009-01-01

    Biotic interactions involving mosquito larvae are context dependent, with effects of interactions on populations altered by ecological conditions. Relative impacts of competition and predation change across a gradient of habitat size and permanence. Asymmetrical competition is common and ecological context changes competitive advantage, potentially facilitating landscape-level coexistence of competitors. Predator effects on mosquito populations sometimes depend on habitat structure and on emergent effects of multiple predators, particularly interference among predators. Nonlethal effects of predators on mosquito oviposition, foraging, and life history are common, and their consequences for populations and for mosquito-borne disease are poorly understood. Context-dependent beneficial effects of detritus shredders on mosquitoes occur in container habitats, but these interactions appear to involve more than simple resource modification by shredders. Investigations of context-dependent interactions among mosquito larvae will yield greater understanding of mosquito population dynamics and provide useful model systems for testing theories of context dependence in communities.

  6. Efficacy of Mosquito Traps for Collecting Potential West Nile Mosquito Vectors in a Natural Mediterranean Wetland

    DEFF Research Database (Denmark)

    Roiz, David; Roussel, Marion; Muñoz, Joaquin;

    2012-01-01

    Surveillance, research, and control of mosquito-borne diseases such asWest Nile virus require efficient methods for sampling mosquitoes. We compared the efficacy of BG-Sentinel and Centers for Disease Control and Prevention (CDC)-CO2 traps in terms of the abundances of host-seeking and blood......-fed female mosquitoes and the origin of mosquito bloodmeals. Our results indicate that BG-Sentinel traps that use CO2 and attractants are as effective as CDC-CO2 traps for Culex mosquito species, Ochlerotatus caspius, and they are also highly efficient at capturing Anopheles atroparvus host-seeking and blood......-fed females with or without CO2. The CDC-CO2 trap is the least efficient method for capturing blood-fed females. BG-Sentinel traps with attractants and CO2 were significantly better at capturing mosquitoes that had fed on mammals than the unbaited BG-Sentinel and CDC-CO2 traps in the cases of An. atroparvus...

  7. Entomopathogenic fungi for mosquito control: A review

    NARCIS (Netherlands)

    Scholte, E.J.; Knols, B.G.J.; Samson, R.A.; Takken, W.

    2004-01-01

    Fungal diseases in insects are common and widespread and can decimate their populations in spectacular epizootics. Virtually all insect orders are susceptible to fungal diseases, including Dipterans. Fungal pathogens such as Lagenidium, Coelomomyces and Culicinomyces are known to affect mosquito pop

  8. Workbook on the Identification of Mosquito Larvae.

    Science.gov (United States)

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable public health workers identify larvae of some important North American mosquito species. The morphological features of larvae of the various genera and species are illustrated in a programed booklet, which also contains illustrated taxonomic keys to the larvae of 11 North American genera and to…

  9. Cultured skin microbiota attracts malaria mosquitoes

    NARCIS (Netherlands)

    Verhulst, N.O.; Beijleveld, H.; Knols, B.G.J.; Takken, W.; Schraa, G.; Bouwmeester, H.J.; Smallegange, R.C.

    2009-01-01

    Background - Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human

  10. Musings on Sketches, Artists, and Mosquito Nets

    Centers for Disease Control (CDC) Podcasts

    2014-09-23

    Byron Breedlove reads his essay Musings on Sketches, Artists, and Mosquito Nets about the art of James Whistler and the transmission of vector borne diseases.  Created: 9/23/2014 by National Center for Emerging and Zoonotic Infectious Diseases (NCEZID).   Date Released: 10/20/2014.

  11. Mosquito repellency of novel Trifluoromethylphenyl amides

    Science.gov (United States)

    Human diseases caused by mosquito-transmitted pathogens include malaria, dengue and yellow fever and are responsible for several million human deaths every year, according to the World Health Organization (WHO). Our current research projects focus on the development of new insecticides and repellent...

  12. Mosquito population regulation and larval source management in heterogeneous environments.

    Directory of Open Access Journals (Sweden)

    David L Smith

    Full Text Available An important question for mosquito population dynamics, mosquito-borne pathogen transmission and vector control is how mosquito populations are regulated. Here we develop simple models with heterogeneity in egg laying patterns and in the responses of larval populations to crowding in aquatic habitats. We use the models to evaluate how such heterogeneity affects mosquito population regulation and the effects of larval source management (LSM. We revisit the notion of a carrying capacity and show how heterogeneity changes our understanding of density dependence and the outcome of LSM. Crowding in and productivity of aquatic habitats is highly uneven unless egg-laying distributions are fine-tuned to match the distribution of habitats' carrying capacities. LSM reduces mosquito population density linearly with coverage if adult mosquitoes avoid laying eggs in treated habitats, but quadratically if eggs are laid in treated habitats and the effort is therefore wasted (i.e., treating 50% of habitat reduces mosquito density by approximately 75%. Unsurprisingly, targeting (i.e. treating a subset of the most productive pools gives much larger reductions for similar coverage, but with poor targeting, increasing coverage could increase adult mosquito population densities if eggs are laid in higher capacity habitats. Our analysis suggests that, in some contexts, LSM models that accounts for heterogeneity in production of adult mosquitoes provide theoretical support for pursuing mosquito-borne disease prevention through strategic and repeated application of modern larvicides.

  13. Transgenesis and reverse genetics of mosquito innate immunity.

    Science.gov (United States)

    Shin, Sang Woon; Kokoza, Vladimir A; Raikhel, Alexander S

    2003-11-01

    In recent years, mosquito molecular biology has been a scene of astounding achievements, namely the development of genetic transformation, characterization of inducible tissue-specific promoters, and acquirement of mosquito genome sequences. However, the lack of a complete genetic tool box for mosquitoes remains a serious obstacle in our ability to study essential mosquito-specific mechanisms. Unlike Drosophila, very few null mutations for mosquito genes exist. The development of reverse-genetic analyses based on RNAi and transgenic techniques will help to compensate for these deficiencies and aid in identification of critical genes in important regulatory pathways. The study of mosquito innate immunity is one example and described here. In this study, we combine mosquito transgenesis with reverse genetics. The advantage of transgenesis is the ability to establish genetically stable, dominant-negative and overexpression phenotypes. Using the blood-meal-activated vitellogenin gene (Vg) promoter, we have generated transgenic mosquitoes with blood-meal-activated, overexpressed antimicrobial peptides, Defensin A and Cecropin A. Moreover, we have recently generated a transgenic dominant-negative Relish mosquito strain, which after taking a blood meal, becomes immune-deficient to infection by Gram-negative bacteria. The latter accomplishment has opened the door to a reverse-genetic approach in mosquitoes based on transgenesis.

  14. Paratransgenesis: a promising new strategy for mosquito vector control.

    Science.gov (United States)

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2015-06-24

    The three main mosquito genera, Anopheles, Aedes and Culex, transmit respectively malaria, dengue and lymphatic filariasis. Current mosquito control strategies have proved unsuccessful, and there still is a substantial number of morbidity and mortality from these diseases. Genetic control methods have now arisen as promising alternative strategies, based on two approaches: the replacement of a vector population by disease-refractory mosquitoes and the release of mosquitoes carrying a lethal gene to suppress target populations. However, substantial hurdles and limitations need to be overcome if these methods are to be used successfully, the most significant being that a transgenic mosquito strain is required for every target species, making genetically modified mosquito strategies inviable when there are multiple vector mosquitoes in the same area. Genetically modified bacteria capable of colonizing a wide range of mosquito species may be a solution to this problem and another option for the control of these diseases. In the paratransgenic approach, symbiotic bacteria are genetically modified and reintroduced in mosquitoes, where they express effector molecules. For this approach to be used in practice, however, requires a better understanding of mosquito microbiota and that symbiotic bacteria and effector molecules be identified. Paratransgenesis could prove very useful in mosquito species that are inherently difficult to transform or in sibling species complexes. In this approach, a genetic modified bacteria can act by: (a) causing pathogenic effects in the host; (b) interfering with the host's reproduction; (c) reducing the vector's competence; and (d) interfering with oogenesis and embryogenesis. It is a much more flexible and adaptable approach than the use of genetically modified mosquitoes because effector molecules and symbiotic bacteria can be replaced if they do not achieve the desired result. Paratransgenesis may therefore become an important integrated

  15. Filarial worms reduce Plasmodium infectivity in mosquitoes.

    Directory of Open Access Journals (Sweden)

    Matthew T Aliota

    Full Text Available BACKGROUND: Co-occurrence of malaria and filarial worm parasites has been reported, but little is known about the interaction between filarial worm and malaria parasites with the same Anopheles vector. Herein, we present data evaluating the interaction between Wuchereria bancrofti and Anopheles punctulatus in Papua New Guinea (PNG. Our field studies in PNG demonstrated that An. punctulatus utilizes the melanization immune response as a natural mechanism of filarial worm resistance against invading W. bancrofti microfilariae. We then conducted laboratory studies utilizing the mosquitoes Armigeres subalbatus and Aedes aegypti and the parasites Brugia malayi, Brugia pahangi, Dirofilaria immitis, and Plasmodium gallinaceum to evaluate the hypothesis that immune activation and/or development by filarial worms negatively impact Plasmodium development in co-infected mosquitoes. Ar. subalbatus used in this study are natural vectors of P. gallinaceum and B. pahangi and they are naturally refractory to B. malayi (melanization-based refractoriness. METHODOLOGY/PRINCIPAL FINDINGS: Mosquitoes were dissected and Plasmodium development was analyzed six days after blood feeding on either P. gallinaceum alone or after taking a bloodmeal containing both P. gallinaceum and B. malayi or a bloodmeal containing both P. gallinaceum and B. pahangi. There was a significant reduction in the prevalence and mean intensity of Plasmodium infections in two species of mosquito that had dual infections as compared to those mosquitoes that were infected with Plasmodium alone, and was independent of whether the mosquito had a melanization immune response to the filarial worm or not. However, there was no reduction in Plasmodium development when filarial worms were present in the bloodmeal (D. immitis but midgut penetration was absent, suggesting that factors associated with penetration of the midgut by filarial worms likely are responsible for the observed reduction in malaria

  16. The Impact of Wolbachia on Virus Infection in Mosquitoes.

    Science.gov (United States)

    Johnson, Karyn N

    2015-11-04

    Mosquito-borne viruses such as dengue, West Nile and chikungunya viruses cause significant morbidity and mortality in human populations. Since current methods are not sufficient to control disease occurrence, novel methods to control transmission of arboviruses would be beneficial. Recent studies have shown that virus infection and transmission in insects can be impeded by co-infection with the bacterium Wolbachia pipientis. Wolbachia is a maternally inherited endosymbiont that is commonly found in insects, including a number of mosquito vector species. In Drosophila, Wolbachia mediates antiviral protection against a broad range of RNA viruses. This discovery pointed to a potential strategy to interfere with mosquito transmission of arboviruses by artificially infecting mosquitoes with Wolbachia. This review outlines research on the prevalence of Wolbachia in mosquito vector species and the impact of antiviral effects in both naturally and artificially Wolbachia-infected mosquitoes.

  17. Arbovirus-mosquito interactions: RNAi pathway.

    Science.gov (United States)

    Olson, Ken E; Blair, Carol D

    2015-12-01

    Arthropod-borne (arbo) viruses infect hematophagous arthropods (vectors) to maintain virus transmission between vertebrate hosts. The mosquito vector actively controls arbovirus infection to minimize its fitness costs. The RNA interference (RNAi) pathway is the major antiviral response vectors use to restrict arbovirus infections. We know this because depleting RNAi gene products profoundly impacts arbovirus replication, the antiviral RNAi pathway genes undergo positive, diversifying selection and arboviruses have evolved strategies to evade the vector's RNAi responses. The vector's RNAi defense and arbovirus countermeasures lead to an arms race that prevents potential virus-induced fitness costs yet maintains arbovirus infections needed for transmission. This review will discuss the latest findings in RNAi-arbovirus interactions in the model insect (Drosophila melanogaster) and in specific mosquito vectors.

  18. Unforeseen costs of cutting mosquito surveillance budgets.

    Directory of Open Access Journals (Sweden)

    Gonzalo M Vazquez-Prokopec

    Full Text Available A budget proposal to stop the U.S. Centers for Disease Control and Prevention (CDC funding in surveillance and research for mosquito-borne diseases such as dengue and West Nile virus has the potential to leave the country ill-prepared to handle new emerging diseases and manage existing ones. In order to demonstrate the consequences of such a measure, if implemented, we evaluated the impact of delayed control responses to dengue epidemics (a likely scenario emerging from the proposed CDC budget cut in an economically developed urban environment. We used a mathematical model to generate hypothetical scenarios of delayed response to a dengue introduction (a consequence of halted mosquito surveillance in the City of Cairns, Queensland, Australia. We then coupled the results of such a model with mosquito surveillance and case management costs to estimate the cumulative costs of each response scenario. Our study shows that halting mosquito surveillance can increase the management costs of epidemics by up to an order of magnitude in comparison to a strategy with sustained surveillance and early case detection. Our analysis shows that the total costs of preparedness through surveillance are far lower than the ones needed to respond to the introduction of vector-borne pathogens, even without consideration of the cost in human lives and well-being. More specifically, our findings provide a science-based justification for the re-assessment of the current proposal to slash the budget of the CDC vector-borne diseases program, and emphasize the need for improved and sustainable systems for vector-borne disease surveillance.

  19. Cultured skin microbiota attracts malaria mosquitoes

    OpenAIRE

    Takken Willem; Knols Bart GJ; Beijleveld Hans; Verhulst Niels O; Schraa Gosse; Bouwmeester Harro J; Smallegange Renate C

    2009-01-01

    Abstract Background Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours. It is hypothesized that host attractiveness and selection of An. gambiae is affected by the species composition, density, and metabolic activity of the skin microbiota. A study ...

  20. Biological Control of Mosquitoes with Mermithids

    OpenAIRE

    Platzer, E. G.

    1981-01-01

    Mermithid nematodes parasitizing mosquitoes have substantial potential for vector control. Studies on the physiological ecology of Romanomermis culicivorax have defined some of the general requirements of mermithid nematodes and produced general guidelines for the experimental release of mermithids in biological control. Experimental field studies have established the biological control potential of R. culicivorax, but further development and ulilization of this parasite will require a substa...

  1. Arctic Health Research Center report no. 101: Combating mosquitoes in arctic Alaska

    Data.gov (United States)

    US Fish and Wildlife Service, Department of the Interior — This report covers combating mosquitoes in Arctic Alaska. The physiology and biology of mosquitoes is discussed, followed by techniques to combated mosquitoes.

  2. Mini Review: Mode of Action of Mosquito Repellents

    Science.gov (United States)

    2013-01-01

    Mini review: Mode of action of mosquito repellents Joseph C. Dickens ⇑, Jonathan D. Bohbot United States Department of Agriculture, Agricultural...Modulation a b s t r a c t The mode of action of mosquito repellents remains a controversial topic. However, electrophysiological studies and molecular...annoyance that can disrupt outdoor activities. The use of repellents decreases contacts between mosquitoes and their hosts, and may even lower the rate of

  3. Susceptibility of Adult Mosquitoes to Insecticides in Aqueous Sucrose Baits

    Science.gov (United States)

    2011-06-01

    of the lack of ingestion as a result of repellency due to high survival of water-deprived control mosquitoes at 24 hr and the abundance of abdomens...Vol. 36, no. 1 Journal of Vector Ecology 59 Susceptibility of adult mosquitoes to insecticides in aqueous sucrose baits Sandra A. Allan Center for...2010 ABSTRACT: Mosquitoes characteristically feed on plant-derived carbohydrates and honeydew just after emergence and intermittently during their

  4. Manipulating insulin signaling to enhance mosquito reproduction

    Directory of Open Access Journals (Sweden)

    Rasgon Jason L

    2009-08-01

    Full Text Available Abstract Backgrond In the mosquito Aedes aegypti the insulin/insulin growth factor I signaling (IIS cascade is a key regulator of many physiological processes, including reproduction. Two important reproductive events, steroidogenesis in the ovary and yolk synthesis in the fat body, are regulated by the IIS cascade in mosquitoes. The signaling molecule phosphatase and tensin homolog (PTEN is a key inhibitor of the IIS cascade that helps modulate the activity of the IIS cascade. In Ae. aegypti, six unique splice variants of AaegPTEN were previously identified, but the role of these splice variants, particularly AaegPTEN3 and 6, were unknown. Results Knockdown of AaegPTEN or its specific splice variant AaegPTEN6 (the splice variant thought to regulate reproduction in the ovary and fat body using RNAi led to a 15–63% increase in egg production with no adverse effects on egg viability during the first reproductive cycle. Knockdown of AaegPTEN3, expressed predominantly in the head, had no effect on reproduction. We also characterized the protein expression patterns of these two splice variants during development and in various tissues during a reproductive cycle. Conclusion Previous studies in a range of organisms, including Drosophila melanogaster and Caenorhabditis elegans, have demonstrated that disruption of the IIS cascade leads to decreased reproduction or sterility. In this study we demonstrate that knockdown of the IIS inhibitor PTEN can actually increase reproduction in the mosquito, at least during the first reproductive cycle.

  5. Mosquito Records from Mexico: The Mosquitoes (Diptera: Culicidae) of Tamaulipas State.

    Science.gov (United States)

    Ortega-Morales, Aldo I; Zavortink, Thomas J; Huerta-Jiménez, Herón; Sánchez-Rámos, Francisco J; Valdés-Perezgasga, Ma Teresa; Reyes-Villanueva, Filiberto; Siller-Rodríguez, Quetzaly K; Fernandez-Salas, Ildefonso

    2015-03-01

    To document the diversity and distribution of mosquito species inhabiting the Mexican state of Tamaulipas, collection trips were conducted to all physiographic regions (Grand Northamerican Plains, Coastal Plain of North Gulf, and Sierra Madre Oriental) and subregions across the state. Additionally, we re-examined mosquito specimens in two Mexican entomological collections: the Collection of Insects and Mites of Medical Importance and the Collection of Arthropods of Medical Importance. In total, 3,931 specimens were collected. These represent the two Culicidae subfamilies Anophelinae and Culicinae, 10 tribes, 17 genera, 27 subgenera, 80 named species, and 2 undescribed species. Of these, 3 tribes, 6 genera, 7 subgenera, and 20 species are new records for the mosquito fauna of Tamaulipas. Fourteen species recorded in the historical records were not found in collections made for this study. Taxonomic notes, new distribution limits, and comments about the medical importance of some of the species collected are reported.

  6. Vector competence of Anopheles and Culex mosquitoes for Zika virus

    Science.gov (United States)

    Dodson, Brittany L.

    2017-01-01

    Zika virus is a newly emergent mosquito-borne flavivirus that has caused recent large outbreaks in the new world, leading to dramatic increases in serious disease pathology including Guillain-Barre syndrome, newborn microcephaly, and infant brain damage. Although Aedes mosquitoes are thought to be the primary mosquito species driving infection, the virus has been isolated from dozens of mosquito species, including Culex and Anopheles species, and we lack a thorough understanding of which mosquito species to target for vector control. We exposed Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes to blood meals supplemented with two Zika virus strains. Mosquito bodies, legs, and saliva were collected five, seven, and 14 days post blood meal and tested for infectious virus by plaque assay. Regardless of titer, virus strain, or timepoint, Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes were refractory to Zika virus infection. We conclude that Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes likely do not contribute significantly to Zika virus transmission to humans. However, future studies should continue to explore the potential for other novel potential vectors to transmit the virus. PMID:28316896

  7. Vector competence of Anopheles and Culex mosquitoes for Zika virus

    Directory of Open Access Journals (Sweden)

    Brittany L. Dodson

    2017-03-01

    Full Text Available Zika virus is a newly emergent mosquito-borne flavivirus that has caused recent large outbreaks in the new world, leading to dramatic increases in serious disease pathology including Guillain-Barre syndrome, newborn microcephaly, and infant brain damage. Although Aedes mosquitoes are thought to be the primary mosquito species driving infection, the virus has been isolated from dozens of mosquito species, including Culex and Anopheles species, and we lack a thorough understanding of which mosquito species to target for vector control. We exposed Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes to blood meals supplemented with two Zika virus strains. Mosquito bodies, legs, and saliva were collected five, seven, and 14 days post blood meal and tested for infectious virus by plaque assay. Regardless of titer, virus strain, or timepoint, Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes were refractory to Zika virus infection. We conclude that Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes likely do not contribute significantly to Zika virus transmission to humans. However, future studies should continue to explore the potential for other novel potential vectors to transmit the virus.

  8. Beer Consumption Increases Human Attractiveness to Malaria Mosquitoes

    Science.gov (United States)

    Lefèvre, Thierry; Gouagna, Louis-Clément; Dabiré, Kounbobr Roch; Elguero, Eric; Fontenille, Didier; Renaud, François; Costantini, Carlo; Thomas, Frédéric

    2010-01-01

    Background Malaria and alcohol consumption both represent major public health problems. Alcohol consumption is rising in developing countries and, as efforts to manage malaria are expanded, understanding the links between malaria and alcohol consumption becomes crucial. Our aim was to ascertain the effect of beer consumption on human attractiveness to malaria mosquitoes in semi field conditions in Burkina Faso. Methodology/Principal Findings We used a Y tube-olfactometer designed to take advantage of the whole body odour (breath and skin emanations) as a stimulus to gauge human attractiveness to Anopheles gambiae (the primary African malaria vector) before and after volunteers consumed either beer (n = 25 volunteers and a total of 2500 mosquitoes tested) or water (n = 18 volunteers and a total of 1800 mosquitoes). Water consumption had no effect on human attractiveness to An. gambiae mosquitoes, but beer consumption increased volunteer attractiveness. Body odours of volunteers who consumed beer increased mosquito activation (proportion of mosquitoes engaging in take-off and up-wind flight) and orientation (proportion of mosquitoes flying towards volunteers' odours). The level of exhaled carbon dioxide and body temperature had no effect on human attractiveness to mosquitoes. Despite individual volunteer variation, beer consumption consistently increased attractiveness to mosquitoes. Conclusions/Significance These results suggest that beer consumption is a risk factor for malaria and needs to be integrated into public health policies for the design of control measures. PMID:20209056

  9. The Plasmodium bottleneck: malaria parasite losses in the mosquito vector

    Directory of Open Access Journals (Sweden)

    Ryan C Smith

    2014-08-01

    Full Text Available Nearly one million people are killed every year by the malaria parasite Plasmodium. Although the disease-causing forms of the parasite exist only in the human blood, mosquitoes of the genus Anopheles are the obligate vector for transmission. Here, we review the parasite life cycle in the vector and highlight the human and mosquito contributions that limit malaria parasite development in the mosquito host. We address parasite killing in its mosquito host and bottlenecks in parasite numbers that might guide intervention strategies to prevent transmission.

  10. Immunological aspects of the immune response induced by mosquito allergens.

    Science.gov (United States)

    Cantillo, José Fernando; Fernández-Caldas, Enrique; Puerta, Leonardo

    2014-01-01

    Allergies caused by mosquito bites may produce local or systemic reactions. The inhalation of mosquito allergens may also cause asthma and/or allergic rhinoconjunctivitis in sensitized individuals. The mechanisms implicated in the development of these immune responses involve IgE antibodies, different subtypes of IgG and proinflammatory cytokines as well as basophils, eosinophils and mast cells. Several allergenic components have been identified in the saliva and bodies of mosquitoes and some of these are present in different mosquito species. The most common species implicated in allergic reactions belong to the genera Aedes, Culex and Anopheles. Several Aedes aegypti allergens have been cloned and sequenced. The recombinant molecules show IgE reactivity similar to that of the native allergens, making them good candidates for the diagnosis of mosquito allergies. Allergen-specific immunotherapy with mosquito extracts induces a protective response characterized by a decreased production of IgE antibodies, increased IgG levels, a reduction in the severity of cutaneous and respiratory symptoms and the need for medication. The aims of this review are to summarize the progress made in the characterization of mosquito allergens and discuss the types of immune responses induced by mosquito bites and the inhalation of mosquito allergens in atopic individuals.

  11. Beer consumption increases human attractiveness to malaria mosquitoes.

    Directory of Open Access Journals (Sweden)

    Thierry Lefèvre

    Full Text Available BACKGROUND: Malaria and alcohol consumption both represent major public health problems. Alcohol consumption is rising in developing countries and, as efforts to manage malaria are expanded, understanding the links between malaria and alcohol consumption becomes crucial. Our aim was to ascertain the effect of beer consumption on human attractiveness to malaria mosquitoes in semi field conditions in Burkina Faso. METHODOLOGY/PRINCIPAL FINDINGS: We used a Y tube-olfactometer designed to take advantage of the whole body odour (breath and skin emanations as a stimulus to gauge human attractiveness to Anopheles gambiae (the primary African malaria vector before and after volunteers consumed either beer (n = 25 volunteers and a total of 2500 mosquitoes tested or water (n = 18 volunteers and a total of 1800 mosquitoes. Water consumption had no effect on human attractiveness to An. gambiae mosquitoes, but beer consumption increased volunteer attractiveness. Body odours of volunteers who consumed beer increased mosquito activation (proportion of mosquitoes engaging in take-off and up-wind flight and orientation (proportion of mosquitoes flying towards volunteers' odours. The level of exhaled carbon dioxide and body temperature had no effect on human attractiveness to mosquitoes. Despite individual volunteer variation, beer consumption consistently increased attractiveness to mosquitoes. CONCLUSIONS/SIGNIFICANCE: These results suggest that beer consumption is a risk factor for malaria and needs to be integrated into public health policies for the design of control measures.

  12. Vector competence of Anopheles and Culex mosquitoes for Zika virus.

    Science.gov (United States)

    Dodson, Brittany L; Rasgon, Jason L

    2017-01-01

    Zika virus is a newly emergent mosquito-borne flavivirus that has caused recent large outbreaks in the new world, leading to dramatic increases in serious disease pathology including Guillain-Barre syndrome, newborn microcephaly, and infant brain damage. Although Aedes mosquitoes are thought to be the primary mosquito species driving infection, the virus has been isolated from dozens of mosquito species, including Culex and Anopheles species, and we lack a thorough understanding of which mosquito species to target for vector control. We exposed Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes to blood meals supplemented with two Zika virus strains. Mosquito bodies, legs, and saliva were collected five, seven, and 14 days post blood meal and tested for infectious virus by plaque assay. Regardless of titer, virus strain, or timepoint, Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes were refractory to Zika virus infection. We conclude that Anopheles gambiae, Anopheles stephensi, and Culex quinquefasciatus mosquitoes likely do not contribute significantly to Zika virus transmission to humans. However, future studies should continue to explore the potential for other novel potential vectors to transmit the virus.

  13. Efficacy of mosquito magnet against mosquitoes%Mosquito Magnet捕蚊器捕蚊效果观察

    Institute of Scientific and Technical Information of China (English)

    胡兴强; 王本富; 刘翠侠; 刘强

    2005-01-01

    Mosquito Magnet是American Biophysics Corp.公司开发的用于诱捕蚊虫的器械,2002年才由安徽大学引入国内使用。有文献报道该器械能捕获大量的蚊虫。为了了解该器械在国内生活小区的捕蚊效果,笔者于23302年6~10月进行了连续观察。

  14. Mosquito-Borne Diseases and Omics: Salivary Gland Proteome of the Female Aedes aegypti Mosquito.

    Science.gov (United States)

    Dhawan, Rakhi; Kumar, Manish; Mohanty, Ajeet Kumar; Dey, Gourav; Advani, Jayshree; Prasad, T S Keshava; Kumar, Ashwani

    2017-01-01

    The female Aedes aegypti mosquito is an important vector for several tropical and subtropical diseases such as dengue, chikungunya, and Zika and yellow fever. The disease viruses infect the mosquito and subsequently spread to the salivary glands after which the viruses can be transmitted to humans with probing or feeding by the mosquito. Omics systems sciences offer the opportunity to characterize vectors and can inform disease surveillance, vector control and development of innovative diagnostics, personalized medicines, vaccines, and insecticide targets. Using high-resolution mass spectrometry, we performed an analysis of the A. aegypti salivary gland proteome. The A. aegypti proteome resulted in acquisition of 83,836 spectra. Upon searches against the protein database of the A. aegypti, these spectra were assigned to 5417 unique peptides, belonging to 1208 proteins. To the best of our knowledge, this is the largest set of proteins identified in the A. aegypti salivary gland. Of note, 29 proteins were involved in immunity-related pathways in salivary glands. A subset of these proteins is known to interact with disease viruses. Another 15 proteins with signal cleavage site were found to be secretory in nature, and thus possibly playing critical roles in blood meal ingestion. These findings provide a baseline to advance our understanding of vector-borne diseases and vector-pathogen interactions before virus transmission in global health, and might therefore enable future design and development of virus-blocking strategies and novel molecular targets in the mosquito vector A. aegypti.

  15. Mosquitoes of field and forest: the scale of habitat segregation in a diverse mosquito assemblage.

    Science.gov (United States)

    Reiskind, M H; Griffin, R H; Janairo, M S; Hopperstad, K A

    2017-03-01

    Knowledge of the distribution of arthropod vectors across a landscape is important in determining the risk for vector-borne disease. This has been well explored for ticks, but not for mosquitoes, despite their importance in the transmission of a variety of pathogens. This study examined the importance of habitat, habitat edges, and the scale at which mosquito abundance and diversity vary in a rural landscape by trapping along transects from grassland areas into forest patches. Significant patterns of vector diversity and distinct mosquito assemblages across habitats were found. The scale of individual species' responses to habitat edges was often dramatic, with several species rarely straying even 10 m from the edge. The present results suggest blood-seeking mosquito species are faithful to certain habitats, which has consequences for patterns of vector diversity and risk for pathogen transmission. This implies that analysts of risk for pathogen transmission and foci of control, and developers of land management strategies should assess habitat at a finer scale than previously considered.

  16. Mosquito transmission of wild turkey malaria, Plasmodium hermani.

    Science.gov (United States)

    Young, M D; Nayar, J K; Forrester, D J

    1977-04-01

    Culex nigripalpus experimentally transmitted Plasmodium hermani, a plasmodium of wild turkeys (Meleagris gallopavo) in Florida. The mosquitoes were infected by feeding upon blood induced parasitemias in domestic turkey poults. The resulting sporozoites, transmitted by either mosquito bites or injection, produced malaria infections in domestic poults.

  17. Visualization of house-entry behaviour of malaria mosquitoes

    NARCIS (Netherlands)

    Spitzen, Jeroen; Koelewijn, Teun; Mukabana, W.R.; Takken, Willem

    2016-01-01

    Background: Malaria mosquitoes often blood feed indoors on human hosts. The mosquitoes predominantly enter houses via open eaves. Host-seeking is odour-driven, and finding a host depends on the quality of the odour plume and whether the route towards the host is free of obstructions. Little is kn

  18. Insect Repellents: Modulators of mosquito odorant receptor activity

    Science.gov (United States)

    Mosquitoes vector numerous pathogens that cause diseases including malaria, yellow fever, dengue fever and chikungunya. DEET, IR3535, Picaridin and 2-undecanone are insect repellents that are used to prevent interactions between humans and a broad array of disease vectors including mosquitoes. While...

  19. Environmental statistical modelling of mosquito vectors at different geographical scales

    NARCIS (Netherlands)

    Cianci, D.

    2015-01-01

    Vector-borne diseases are infections transmitted by the bite of infected arthropod vectors, such as mosquitoes, ticks, fleas, midges and flies. Vector-borne diseases pose an increasingly wider threat to global public health, both in terms of people affected and their geographical spread. Mosquitoes

  20. UV light and urban pollution: Bad cocktail for mosquitoes?

    Energy Technology Data Exchange (ETDEWEB)

    Tetreau, Guillaume, E-mail: guillaume.tetreau@gmail.com [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France); Department of Entomology, Cornell University, New York State Agricultural Experiment Station, Geneva, NY 14456 (United States); Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud’homme, Sophie M.; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane [Laboratoire d’Ecologie Alpine, LECA-UMR 5553, Université de Grenoble 1, BP 53, 38041 Grenoble cedex 09 (France)

    2014-01-15

    Highlights: •Mosquito tolerance to temephos is induced by PAHs and UV exposure. •Toxicity of fluoranthene for mosquito Malpighian tubules cells is induced by UV. •Fluoranthene crystallizes in mosquito Malpighian tubules upon UV exposure. •Mixture of two PAHs is less toxic for mosquitoes than each PAHs separately. •Combination of abiotic parameters (PAHs and UV) affect mosquito physiology. -- Abstract: Mosquito breeding sites consist of water pools, which can either be large open areas or highly covered ponds with vegetation, thus with different light exposures combined with the presence in water of xenobiotics including polycyclic aromatic hydrocarbons (PAHs) generated by urban pollution. UV light and PAHs are abiotic factors known to both affect the mosquito insecticide resistance status. Nonetheless, their potential combined effects on the mosquito physiology have never been investigated. The present article aims at describing the effects of UV exposure alongside water contamination with two major PAH pollutants (fluoranthene and benzo[a]pyrene) on a laboratory population of the yellow fever mosquito Aedes aegypti. To evaluate the effects of PAH exposure and low energetic UV (UV-A) irradiation on mosquitoes, different parameters were measured including: (1) The PAH localization and its impact on cell mortality by fluorescent microscopy; (2) The detoxification capacities (cytochrome P450, glutathione-S-transferase, esterase); (3) The responses to oxidative stress (Reactive Oxygen Species–ROS) and (4) The tolerance of mosquito larvae to a bioinsecticide (Bacillus thuringiensis subsp. israelensis–Bti) and to five chemical insecticides (DDT, imidacloprid, permethrin, propoxur and temephos). Contrasting effects regarding mosquito cell mortality, detoxification and oxidative stress were observed as being dependent on the pollutant considered, despite the fact that the two PAHs belong to the same family. Moreover, UV is able to modify pollutant effects on

  1. Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission

    Science.gov (United States)

    Roundy, Christopher M.; Azar, Sasha R.; Rossi, Shannan L.; Huang, Jing H.; Leal, Grace; Yun, Ruimei; Fernandez-Salas, Ildefonso; Vitek, Christopher J.; Paploski, Igor A.D.; Kitron, Uriel; Ribeiro, Guilherme S.; Hanley, Kathryn A.

    2017-01-01

    To test whether Zika virus has adapted for more efficient transmission by Aedes aegypti mosquitoes, leading to recent urban outbreaks, we fed mosquitoes from Brazil, the Dominican Republic, and the United States artificial blood meals containing 1 of 3 Zika virus strains (Senegal, Cambodia, Mexico) and monitored infection, dissemination, and virus in saliva. Contrary to our hypothesis, Cambodia and Mexica strains were less infectious than the Senegal strain. Only mosquitoes from the Dominican Republic transmitted the Cambodia and Mexica strains. However, blood meals from viremic mice were more infectious than artificial blood meals of comparable doses; the Cambodia strain was not transmitted by mosquitoes from Brazil after artificial blood meals, whereas 61% transmission occurred after a murine blood meal (saliva titers up to 4 log10 infectious units/collection). Although regional origins of vector populations and virus strain influence transmission efficiency, Ae. aegypti mosquitoes appear to be competent vectors of Zika virus in several regions of the Americas. PMID:28287375

  2. Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission.

    Science.gov (United States)

    Roundy, Christopher M; Azar, Sasha R; Rossi, Shannan L; Huang, Jing H; Leal, Grace; Yun, Ruimei; Fernandez-Salas, Ildefonso; Vitek, Christopher J; Paploski, Igor A D; Kitron, Uriel; Ribeiro, Guilherme S; Hanley, Kathryn A; Weaver, Scott C; Vasilakis, Nikos

    2017-04-01

    To test whether Zika virus has adapted for more efficient transmission by Aedes aegypti mosquitoes, leading to recent urban outbreaks, we fed mosquitoes from Brazil, the Dominican Republic, and the United States artificial blood meals containing 1 of 3 Zika virus strains (Senegal, Cambodia, Mexico) and monitored infection, dissemination, and virus in saliva. Contrary to our hypothesis, Cambodia and Mexica strains were less infectious than the Senegal strain. Only mosquitoes from the Dominican Republic transmitted the Cambodia and Mexica strains. However, blood meals from viremic mice were more infectious than artificial blood meals of comparable doses; the Cambodia strain was not transmitted by mosquitoes from Brazil after artificial blood meals, whereas 61% transmission occurred after a murine blood meal (saliva titers up to 4 log 10 infectious units/collection). Although regional origins of vector populations and virus strain influence transmission efficiency, Ae. aegypti mosquitoes appear to be competent vectors of Zika virus in several regions of the Americas.

  3. Field evaluation of herbal mosquito repellents.

    Science.gov (United States)

    Das, N G; Nath, D R; Baruah, I; Talukdar, P K; Das, S C

    1999-12-01

    Repellent properties of Zanthoxylum armatum DC. Syn. Z. alatum Roxb. (Timur), Curcuma aromatica (Jungli haldi) and Azadirachta indica (Neem) oils were evaluated against mosquitoes in mustard (Brassica sp.) and coconut (Cocos sp.) oil base and compared with synthetic repellent. Dimethyl phthalate (DMP) as standard. Timur and jungli haldi afforded better protection in the both the base at all the concentrations. Tepellents in mustard oil gave longer protection time than those in coconut oil. At 0.57 mg/cm2 concentration timur oil gave significantly higher protection both in mustard (445 min) as well as coconut oil (404 min) than the other repellents and DMP.

  4. Does polyandrous impede mosquito control by autocidal?

    Directory of Open Access Journals (Sweden)

    K.Jayaprakash

    2014-03-01

    Full Text Available Vector mosquito control by releasing genetically altered males has been attempted under the presumption that the females are monandrous. The present observation was through the sex–linked inheritance pattern of eye-colour and the estimation of polyandrous in in-vitro mating. A small proportion (18.2% of the female Anopheles stephensi population exhibited polyandrous on examination of 850 F1 adults when two types of males (white and black eyed where allowed to mate with homozygous white eyed females. The above results were discussed with relation to the consequences of the polyandrous trait in sterile insect technique, genetic control programmes.

  5. Novel acetylcholinesterase target site for malaria mosquito control.

    Directory of Open Access Journals (Sweden)

    Yuan-Ping Pang

    Full Text Available Current anticholinesterase pesticides were developed during World War II and are toxic to mammals because they target a catalytic serine residue of acetylcholinesterases (AChEs in insects and in mammals. A sequence analysis of AChEs from 73 species and a three-dimensional model of a malaria-carrying mosquito (Anopheles gambiae AChE (AgAChE reported here show that C286 and R339 of AgAChE are conserved at the opening of the active site of AChEs in 17 invertebrate and four insect species, respectively. Both residues are absent in the active site of AChEs of human, monkey, dog, cat, cattle, rabbit, rat, and mouse. The 17 invertebrates include house mosquito, Japanese encephalitis mosquito, African malaria mosquito, German cockroach, Florida lancelet, rice leaf beetle, African bollworm, beet armyworm, codling moth, diamondback moth, domestic silkworm, honey bee, oat or wheat aphid, the greenbug, melon or cotton aphid, green peach aphid, and English grain aphid. The four insects are house mosquito, Japanese encephalitis mosquito, African malaria mosquito, and German cockroach. The discovery of the two invertebrate-specific residues enables the development of effective and safer pesticides that target the residues present only in mosquito AChEs rather than the ubiquitous serine residue, thus potentially offering an effective control of mosquito-borne malaria. Anti-AgAChE pesticides can be designed to interact with R339 and subsequently covalently bond to C286. Such pesticides would be toxic to mosquitoes but not to mammals.

  6. Human skin emanations in the host-seeking behaviour of the malaria mosquito Anopheles gambiae

    NARCIS (Netherlands)

    Braks, M.A.H.

    1999-01-01

    Malaria is an infectious disease caused by a parasite ( Plasmodium spp.) that is transmitted between human individuals by mosquitoes, belonging to the order of insects, Diptera, family of Culicidae (mosquitoes) and genus of Anopheles (malaria mosquitoes). Mosquitoes feed on humans (and other animals

  7. Laser induced mortality of Anopheles stephensi mosquitoes

    Science.gov (United States)

    Keller, Matthew D.; Leahy, David J.; Norton, Bryan J.; Johanson, Threeric; Mullen, Emma R.; Marvit, Maclen; Makagon, Arty

    2016-02-01

    Small, flying insects continue to pose great risks to both human health and agricultural production throughout the world, so there remains a compelling need to develop new vector and pest control approaches. Here, we examined the use of short (mosquitoes, which were chosen as a representative species. The mortality of mosquitoes exposed to laser pulses of various wavelength, power, pulse duration, and spot size combinations was assessed 24 hours after exposure. For otherwise comparable conditions, green and far-infrared wavelengths were found to be more effective than near- and mid-infrared wavelengths. Pulses with larger laser spot sizes required lower lethal energy densities, or fluence, but more pulse energy than for smaller spot sizes with greater fluence. Pulse duration had to be reduced by several orders of magnitude to significantly lower the lethal pulse energy or fluence required. These results identified the most promising candidates for the lethal laser component in a system being designed to identify, track, and shoot down flying insects in the wild.

  8. Tissue Barriers to Arbovirus Infection in Mosquitoes.

    Science.gov (United States)

    Franz, Alexander W E; Kantor, Asher M; Passarelli, A Lorena; Clem, Rollie J

    2015-07-08

    Arthropod-borne viruses (arboviruses) circulate in nature between arthropod vectors and vertebrate hosts. Arboviruses often cause devastating diseases in vertebrate hosts, but they typically do not cause significant pathology in their arthropod vectors. Following oral acquisition of a viremic bloodmeal from a vertebrate host, the arbovirus disease cycle requires replication in the cellular environment of the arthropod vector. Once the vector has become systemically and persistently infected, the vector is able to transmit the virus to an uninfected vertebrate host. In order to systemically infect the vector, the virus must cope with innate immune responses and overcome several tissue barriers associated with the midgut and the salivary glands. In this review we describe, in detail, the typical arbovirus infection route in competent mosquito vectors. Based on what is known from the literature, we explain the nature of the tissue barriers that arboviruses are confronted with in a mosquito vector and how arboviruses might surmount these barriers. We also point out controversial findings to highlight particular areas that are not well understood and require further research efforts.

  9. Selective and irreversible inhibitors of mosquito acetylcholinesterases for controlling malaria and other mosquito-borne diseases.

    Directory of Open Access Journals (Sweden)

    Yuan-Ping Pang

    Full Text Available New insecticides are urgently needed because resistance to current insecticides allows resurgence of disease-transmitting mosquitoes while concerns for human toxicity from current compounds are growing. We previously reported the finding of a free cysteine (Cys residue at the entrance of the active site of acetylcholinesterase (AChE in some insects but not in mammals, birds, and fish. These insects have two AChE genes (AP and AO, and only AP-AChE carries the Cys residue. Most of these insects are disease vectors such as the African malaria mosquito (Anopheles gambiae sensu stricto or crop pests such as aphids. Recently we reported a Cys-targeting small molecule that irreversibly inhibited all AChE activity extracted from aphids while an identical exposure caused no effect on the human AChE. Full inhibition of AChE in aphids indicates that AP-AChE contributes most of the enzymatic activity and suggests that the Cys residue might serve as a target for developing better aphicides. It is therefore worth investigating whether the Cys-targeting strategy is applicable to mosquitocides. Herein, we report that, under conditions that spare the human AChE, a methanethiosulfonate-containing molecule at 6 microM irreversibly inhibited 95% of the AChE activity extracted from An. gambiae s. str. and >80% of the activity from the yellow fever mosquito (Aedes aegypti L. or the northern house mosquito (Culex pipiens L. that is a vector of St. Louis encephalitis. This type of inhibition is fast ( approximately 30 min and due to conjugation of the inhibitor to the active-site Cys of mosquito AP-AChE, according to our observed reactivation of the methanethiosulfonate-inhibited AChE by 2-mercaptoethanol. We also note that our sulfhydryl agents partially and irreversibly inhibited the human AChE after prolonged exposure (>4 hr. This slow inhibition is due to partial enzyme denaturation by the inhibitor and/or micelles of the inhibitor, according to our studies using

  10. Plasmodium infection decreases fecundity and increases survival of mosquitoes.

    Science.gov (United States)

    Vézilier, J; Nicot, A; Gandon, S; Rivero, A

    2012-10-07

    Long-lived mosquitoes maximize the chances of Plasmodium transmission. Yet, in spite of decades of research, the effect of Plasmodium parasites on mosquito longevity remains highly controversial. On the one hand, many studies report shorter lifespans in infected mosquitoes. On the other hand, parallel (but separate) studies show that Plasmodium reduces fecundity and imply that this is an adaptive strategy of the parasite aimed at redirecting resources towards longevity. No study till date has, however, investigated fecundity and longevity in the same individuals to see whether this prediction holds. In this study, we follow for both fecundity and longevity in Plasmodium-infected and uninfected mosquitoes using a novel, albeit natural, experimental system. We also explore whether the genetic variations that arise through the evolution of insecticide resistance modulate the effect of Plasmodium on these two life-history traits. We show that (i) a reduction in fecundity in Plasmodium-infected mosquitoes is accompanied by an increase in longevity; (ii) this increase in longevity arises through a trade-off between reproduction and survival; and (iii) in insecticide-resistant mosquitoes, the slope of this trade-off is steeper when the mosquito is infected by Plasmodium (cost of insecticide resistance).

  11. The Knowledge and Experience of Dengue Mosquitoes among Housewives.

    Directory of Open Access Journals (Sweden)

    Atik Triratnawati

    2011-06-01

    Full Text Available Dengue Hemorrhagic Fever (DHF prevention programs in Semarang, were focused through controlling mosquito breeding sites (PSN, but the implementation of PSN was not become a habit in every household. The objective of this study was to explore knowledge and experience of dengue mosquitoes among housewives in the endemic villages.The research was using qualitative methods. Subjects of the study were 17 housewives which selected by purposive sampling. The data collection was carried in Sendangmulyo village, Semarang, through observation, focus groups discussions, and indepth interviews. The techniques used to test data validity were triangulation and member checking method. Data were analyzed using content analysis approached. The results showed that housewives classifying mosquito based on time occurrence whether the presence of mosquito in environment was perceived naturally. Unoptimalized PSN behavior was based on the lack of housewives knowledge on larvae development stages. Mosquito was not considered as a threatening because night mosquito biting was directly more disturbing rather than day mosquitoes’. Health promotion program could increase dasa wisma cadres knowledge and skill, particularly on mosquito life cycle and the correct stages of PSN behavior. This study did not distinguish the demographic characteristics of informants. Further reserch could explore it or develop media based on local knowledge and experience.

  12. Does Zika virus infection affect mosquito response to repellents?

    Science.gov (United States)

    Leal, Walter S.; Barbosa, Rosângela M. R.; Zeng, Fangfang; Faierstein, Gabriel B.; Tan, Kaiming; Paiva, Marcelo H. S.; Guedes, Duschinka R. D.; Crespo, Mônica M.; Ayres, Constância F. J.

    2017-01-01

    The World Health Organization (WHO) recommends that people travelling to or living in areas with Zika virus (ZIKV) outbreaks or epidemics adopt prophylactic measures to reduce or eliminate mosquito bites, including the use of insect repellents. It is, however, unknown whether repellents are effective against ZIKV-infected mosquitoes, in part because of the ethical concerns related to exposing a human subject’s arm to infected mosquitoes in the standard arm-in-cage assay. We used a previously developed, human subject-free behavioural assay, which mimics a human subject to evaluate the top two recommended insect repellents. Our measurements showed that DEET provided significantly higher protection than picaridin provided against noninfected, host-seeking females of the southern house mosquito, Culex quinquefasciatus, and the yellow fever mosquito, Aedes aegypti. When tested at lower doses, we observed a significant reduction in DEET-elicited protection against ZIKV-infected yellow fever mosquitoes from old and recent laboratory colonies. The reduction in protection is more likely associated with aging than the virus infection and could be compensated by applying a 5x higher dose of DEET. A substantial protection against ZIKV-infected and old noninfected mosquitoes was achieved with 5% DEET, which corresponds approximately to a 30% dose in the conventional arm-in-cage assays. PMID:28205633

  13. Mosquito repellent activity of volatile oils from selected aromatic plants.

    Science.gov (United States)

    Lalthazuali; Mathew, Nisha

    2017-02-01

    Essential oils from fresh leaves of four aromatic plants viz., Ocimum sanctum, Mentha piperita, Eucalyptus globulus and Plectranthus amboinicus were extracted by hydrodistillation. The test solutions were prepared as 20% essential oil in ethanol and positive control as 20% DEET in ethanol. Essential oil blend was prepared as 5% concentration. Nulliparous, 3-5-day-old female adult Aedes aegypti mosquitoes were used for repellency screening as per ICMR protocol. The study showed that the repellency of 20% essential oil of O. sanctum, M. piperita and P. amboinicus were comparable with that of the standard DEET (20%) as no mosquito landing on the test was observed up to 6 h. The E. globulus oil exhibited mosquito repellency only upto 1½ h. Considerable mosquito landing and feeding was displayed in negative control. In the case of the oil blend, no landing of mosquitoes was seen up to 6 h as that of positive control. The results showed that the essential oil blend from O. sanctum, M. piperita, E. globulus and P. amboinicus could repel Ae. aegypti mosquitoes or prevent from feeding as in the case of DEET even at a lower concentration of 5%. This study demonstrates the potential of essential oils from O. sanctum, M. piperita, E. globulus and P. amboinicus and their blend as mosquito repellents against Ae. aegypti, the vector of dengue, chikungunya and yellow fever.

  14. Effects of landscape anthropization on mosquito community composition and abundance

    Science.gov (United States)

    Ferraguti, Martina; Martínez-de La Puente, Josué; Roiz, David; Ruiz, Santiago; Soriguer, Ramón; Figuerola, Jordi

    2016-07-01

    Anthropogenic landscape transformation has an important effect on vector-borne pathogen transmission. However, the effects of urbanization on mosquito communities are still only poorly known. Here, we evaluate how land-use characteristics are related to the abundance and community composition of mosquitoes in an area with endemic circulation of numerous mosquito-borne pathogens. We collected 340 829 female mosquitoes belonging to 13 species at 45 localities spatially grouped in 15 trios formed by 1 urban, 1 rural and 1 natural area. Mosquito abundance and species richness were greater in natural and rural areas than in urban areas. Environmental factors including land use, vegetation and hydrological characteristics were related to mosquito abundance and community composition. Given the differing competences of each species in pathogen transmission, these results provide valuable information on the transmission potential of mosquito-borne pathogens that will be of great use in public and animal health management by allowing, for instance, the identification of the priority areas for pathogen surveillance and vector control.

  15. Mosquito Control in Poland: Pro- and Anti-Environmental Activities

    Directory of Open Access Journals (Sweden)

    Gliniewicz Aleksandra

    2014-12-01

    Full Text Available Mosquito control in Poland is still dominated by the use of chemicals. Although it has been 13 years since the flood of the century, only in few cities and towns (Wroclaw, Gorzow Wielkopolski and Torun various methods of mosquito control such as mapping of larvae development and setting time limits for the imagines occur-rence were developed. The problem of mosquito control is not only limited to adult insects, it is also much more a complex issue due to the use of insecticides in the environment that we would rather like to keep unchanged, with a diversity of co-existing species of plants and animals. In addition to eradication of larvae and adult insects, we should also: carry out actions modifying environment so that it becomes less friendly to mosquitoes (e.g. drying wet mead-ows as a result of land reclamation, protect places where people reside - with the use of insecticide lamps and spatial repellents, as well as catchers for aggressive female mosquitoes. Increasing the share of environmental management methods and public education on preventing to form and eliminating existing places of mosquito larvae development in urban green areas (parks, river overflow areas and drainage ditches are still an undervalued element of integrated mosquito control in Poland.

  16. Morphometric Wing Characters as a Tool for Mosquito Identification

    Science.gov (United States)

    Christe, Rafael de Oliveira; Multini, Laura Cristina; Vidal, Paloma Oliveira; Wilk-da-Silva, Ramon; de Carvalho, Gabriela Cristina; Marrelli, Mauro Toledo

    2016-01-01

    Mosquitoes are responsible for the transmission of important infectious diseases, causing millions of deaths every year and endangering approximately 3 billion people around the world. As such, precise identification of mosquito species is crucial for an understanding of epidemiological patterns of disease transmission. Currently, the most common method of mosquito identification relies on morphological taxonomic keys, which do not always distinguish cryptic species. However, wing geometric morphometrics is a promising tool for the identification of vector mosquitoes, sibling and cryptic species included. This study therefore sought to accurately identify mosquito species from the three most epidemiologically important mosquito genera using wing morphometrics. Twelve mosquito species from three epidemiologically important genera (Aedes, Anopheles and Culex) were collected and identified by taxonomic keys. Next, the right wing of each adult female mosquito was removed and photographed, and the coordinates of eighteen digitized landmarks at the intersections of wing veins were collected. The allometric influence was assessed, and canonical variate analysis and thin-plate splines were used for species identification. Cross-validated reclassification tests were performed for each individual, and a Neighbor Joining tree was constructed to illustrate species segregation patterns. The analyses were carried out and the graphs plotted with TpsUtil 1.29, TpsRelw 1.39, MorphoJ 1.02 and Past 2.17c. Canonical variate analysis for Aedes, Anopheles and Culex genera showed three clear clusters in morphospace, correctly distinguishing the three mosquito genera, and pairwise cross-validated reclassification resulted in at least 99% accuracy; subgenera were also identified correctly with a mean accuracy of 96%, and in 88 of the 132 possible comparisons, species were identified with 100% accuracy after the data was subjected to reclassification. Our results showed that Aedes, Culex

  17. Current status of genome editing in vector mosquitoes: A review.

    Science.gov (United States)

    Reegan, Appadurai Daniel; Ceasar, Stanislaus Antony; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu; Al-Dhabi, Naif Abdullah

    2017-01-16

    Mosquitoes pose a major threat to human health as they spread many deadly diseases like malaria, dengue, chikungunya, filariasis, Japanese encephalitis and Zika. Identification and use of novel molecular tools are essential to combat the spread of vector borne diseases. Genome editing tools have been used for the precise alterations of the gene of interest for producing the desirable trait in mosquitoes. Deletion of functional genes or insertion of toxic genes in vector mosquitoes will produce either knock-out or knock-in mutants that will check the spread of vector-borne diseases. Presently, three types of genome editing tools viz., zinc finger nuclease (ZFN), transcription activator-like effector nucleases (TALEN) and clustered regulatory interspaced short palindromic repeats (CRISPR) and CRISPR associated protein 9 (Cas9) are widely used for the editing of the genomes of diverse organisms. These tools are also applied in vector mosquitoes to control the spread of vector-borne diseases. A few studies have been carried out on genome editing to control the diseases spread by vector mosquitoes and more studies need to be performed with the utilization of more recently invented tools like CRISPR/Cas9 to combat the spread of deadly diseases by vector mosquitoes. The high specificity and flexibility of CRISPR/Cas9 system may offer possibilities for novel genome editing for the control of important diseases spread by vector mosquitoes. In this review, we present the current status of genome editing research on vector mosquitoes and also discuss the future applications of vector mosquito genome editing to control the spread of vectorborne diseases.

  18. A systematic review of mosquito coils and passive emanators: defining recommendations for spatial repellency testing methodologies

    OpenAIRE

    Ogoma Sheila B; Moore Sarah J; Maia Marta F

    2012-01-01

    Abstract Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and ...

  19. A Systematic Review of Mosquito Coils and Passive Emanators: Defining Recommendations for Spatial Repellency Testing Methodologies.

    OpenAIRE

    Ogoma, SB; Moore, SJ; Maia, MF

    2012-01-01

    Mosquito coils, vaporizer mats and emanators confer protection against mosquito bites through the spatial action of emanated vapor or airborne pyrethroid particles. These products dominate the pest control market; therefore, it is vital to characterize mosquito responses elicited by the chemical actives and their potential for disease prevention. The aim of this review was to determine effects of mosquito coils and emanators on mosquito responses that reduce human-vector contact and to propos...

  20. Blocking malaria parasite invasion of mosquito salivary glands.

    Science.gov (United States)

    James, Anthony A

    2003-11-01

    Release of genetically engineered mosquitoes resistant to parasite infections has been proposed as a novel way to control malaria transmission, and several important advances have been made in anticipation of testing this approach. In particular, the development of synthetic effector genes that block parasite development in mosquito hosts has exploited a number of different mechanisms that result in parasite-resistant phenotypes, and those that target specifically the sporozoites are reviewed here. The use of a number of synthetic genes based on different mechanisms in transgenic mosquitoes will make the selection of resistant parasites unlikely.

  1. Annotated checklist of the mosquitoes of the Republic of Moldova.

    Science.gov (United States)

    Sulesco, Tatiana M; Toderas, Ion K; Toderas, Lidia G

    2013-06-01

    The mosquito fauna of the Republic of Moldova is poorly known. In an effort to understand the Culicidae fauna better, mosquito collections have been conducted between early April and middle November from 2008 to 2012. A total of 10,923 larval specimens and 8,246 adults were collected from 20 regions of Moldova. Altogether 36 species have been recorded during the recent study, bringing the total Moldovan mosquito fauna to 40 species in 9 genera and 11 subgenera. New state records include the following 7 species: Anopheles pseudopictus, An. melanoon, Aedes geminus, Culex torrentium, Culiseta longiareolata, Coquillettidia buxtoni, and Uranotaenia unguiculata.

  2. Modelling the Active Hearing Process in Mosquitoes

    Science.gov (United States)

    Avitabile, Daniele; Homer, Martin; Jackson, Joe; Robert, Daniel; Champneys, Alan

    2011-11-01

    A simple microscopic mechanistic model is described of the active amplification within the Johnston's organ of the mosquito species Toxorhynchites brevipalpis. The model is based on the description of the antenna as a forced-damped oscillator coupled to a set of active threads (ensembles of scolopidia) that provide an impulsive force when they twitch. This twitching is in turn controlled by channels that are opened and closed if the antennal oscillation reaches a critical amplitude. The model matches both qualitatively and quantitatively with recent experiments. New results are presented using mathematical homogenization techniques to derive a mesoscopic model as a simple oscillator with nonlinear force and damping characteristics. It is shown how the results from this new model closely resemble those from the microscopic model as the number of threads approach physiologically correct values.

  3. A Multicomponent Animal Virus Isolated from Mosquitoes.

    Science.gov (United States)

    Ladner, Jason T; Wiley, Michael R; Beitzel, Brett; Auguste, Albert J; Dupuis, Alan P; Lindquist, Michael E; Sibley, Samuel D; Kota, Krishna P; Fetterer, David; Eastwood, Gillian; Kimmel, David; Prieto, Karla; Guzman, Hilda; Aliota, Matthew T; Reyes, Daniel; Brueggemann, Ernst E; St John, Lena; Hyeroba, David; Lauck, Michael; Friedrich, Thomas C; O'Connor, David H; Gestole, Marie C; Cazares, Lisa H; Popov, Vsevolod L; Castro-Llanos, Fanny; Kochel, Tadeusz J; Kenny, Tara; White, Bailey; Ward, Michael D; Loaiza, Jose R; Goldberg, Tony L; Weaver, Scott C; Kramer, Laura D; Tesh, Robert B; Palacios, Gustavo

    2016-09-14

    RNA viruses exhibit a variety of genome organization strategies, including multicomponent genomes in which each segment is packaged separately. Although multicomponent genomes are common among viruses infecting plants and fungi, their prevalence among those infecting animals remains unclear. We characterize a multicomponent RNA virus isolated from mosquitoes, designated Guaico Culex virus (GCXV). GCXV belongs to a diverse clade of segmented viruses (Jingmenvirus) related to the prototypically unsegmented Flaviviridae. The GCXV genome comprises five segments, each of which appears to be separately packaged. The smallest segment is not required for replication, and its presence is variable in natural infections. We also describe a variant of Jingmen tick virus, another Jingmenvirus, sequenced from a Ugandan red colobus monkey, thus expanding the host range of this segmented and likely multicomponent virus group. Collectively, this study provides evidence for the existence of multicomponent animal viruses and their potential relevance for animal and human health.

  4. Assessing the impacts of truck based ultra-low volume applications of mosquito adulticides on honey bees (Apis mellifera)

    Science.gov (United States)

    Mosquito control reduces populations of mosquitoes to minimize the risk of mosquito-borne diseases. As part of an integrated approach to mosquito control, application of adulticides can be effective in rapidly reducing mosquito populations during times of high arbovirus transmission. However, impact...

  5. Vector competence of New Zealand mosquitoes for selected arboviruses.

    Science.gov (United States)

    Kramer, Laura D; Chin, Pam; Cane, Rachel P; Kauffman, Elizabeth B; Mackereth, Graham

    2011-07-01

    New Zealand (NZ) historically has been free of arboviral activity with the exception of Whataroa virus (Togaviridae: Alphavirus), which is established in bird populations and is transmitted by local mosquitoes. This naive situation is threatened by global warming, invasive mosquitoes, and tourism. To determine the threat of selected medically important arboviruses to NZ, vector competence assays were conducted using field collected endemic and introduced mosquito species. Four alphaviruses (Togaviridae): Barmah Forest virus, Chikungunya virus, Ross River virus, and Sindbis virus, and five flaviviruses (Flaviviridae): Dengue virus 2, Japanese encephalitis virus, Murray Valley encephalitis virus, West Nile virus, and Yellow fever virus were evaluated. Results indicate some NZ mosquito species are highly competent vectors of selected arboviruses, particularly alphaviruses, and may pose a threat were one of these arboviruses introduced at a time when the vector was prevalent and the climatic conditions favorable for virus transmission.

  6. Comparative repellency of 38 essential oils against mosquito bites.

    Science.gov (United States)

    Trongtokit, Yuwadee; Rongsriyam, Yupha; Komalamisra, Narumon; Apiwathnasorn, Chamnarn

    2005-04-01

    The mosquito repellent activity of 38 essential oils from plants at three concentrations was screened against the mosquito Aedes aegypti under laboratory conditions using human subjects. On a volunteer's forearm, 0.1 mL of oil was applied per 30 cm2 of exposed skin. When the tested oils were applied at a 10% or 50% concentration, none of them prevented mosquito bites for as long as 2 h, but the undiluted oils of Cymbopogon nardus (citronella), Pogostemon cablin (patchuli), Syzygium aromaticum (clove) and Zanthoxylum limonella (Thai name: makaen) were the most effective and provided 2 h of complete repellency. From these initial results, three concentrations (10%, 50% and undiluted) of citronella, patchouli, clove and makaen were selected for repellency tests against Culex quinquefasciatus and Anopheles dirus. As expected, the undiluted oil showed the highest protection in each case. Clove oil gave the longest duration of 100% repellency (2-4 h) against all three species of mosquito.

  7. Help Control Mosquitoes that Spread Dengue, Chikungunya, and Zika Viruses

    Science.gov (United States)

    Help Control Mosquitoes that Spread Dengue, Chikungunya, and Zika Viruses B Z Z Z Z . Aside from ... or Aedes albopictus ) can spread dengue, chikungunya, or Zika viruses. People become infected with dengue, chikungunya, or ...

  8. Biological Control of Mosquito Vectors: Past, Present, and Future

    Directory of Open Access Journals (Sweden)

    Giovanni Benelli

    2016-10-01

    Full Text Available Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs is available for most of these diseases andvectorcontrolisstillthemainformofprevention. Thelimitationsoftraditionalinsecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In thisreview, weoutline non-insecticide basedstrategiesthat havebeenimplemented orare currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies.

  9. Potential for New York mosquitoes to transmit West Nile virus.

    Science.gov (United States)

    Turell, M J; O'Guinn, M; Oliver, J

    2000-03-01

    We evaluated the potential for several North American mosquito species to transmit the newly introduced West Nile (WN) virus. Mosquitoes collected in the New York City Metropolitan Area during the recent (1999) WN outbreak were allowed to feed on chickens infected with WN virus isolated from a crow that had died during this outbreak. These mosquitoes were tested approximately 2 weeks later to determine infection, dissemination, and transmission rates. Culex pipiens mosquitoes were highly susceptible to infection, and nearly all individuals with a disseminated infection did transmit WN virus by bite. In contrast, Aedes vexans were only moderately susceptible to oral infection; however, those individuals inoculated with WN virus did transmit virus by bite.

  10. Laminin and the malaria parasite's journey through the mosquito midgut.

    Science.gov (United States)

    Arrighi, Romanico B G; Lycett, Gareth; Mahairaki, Vassiliki; Siden-Kiamos, Inga; Louis, Christos

    2005-07-01

    During the invasion of the mosquito midgut epithelium, Plasmodium ookinetes come to rest on the basal lamina, where they transform into the sporozoite-producing oocysts. Laminin, one of the basal lamina's major components, has previously been shown to bind several surface proteins of Plasmodium ookinetes. Here, using the recently developed RNAi technique in mosquitoes, we used a specific dsRNA construct targeted against the LANB2 gene (laminin gamma1) of Anopheles gambiae to reduce its mRNA levels, leading to a substantial reduction in the number of successfully developed oocysts in the mosquito midgut. Moreover, this molecular relationship is corroborated by the intimate association of developing P. berghei parasites and laminin in the gut, as observed using confocal microscopy. Our data support the notion of laminin playing a functional role in the development of the malaria parasite within the mosquito midgut.

  11. Fungal infection counters insecticide resistance in African malaria mosquitoes

    NARCIS (Netherlands)

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

    2009-01-01

    The evolution of insecticide resistance in mosquitoes is threatening the effectiveness and sustainability of malaria control programs in various parts of the world. Through their unique mode of action, entomopathogenic fungi provide promising alternatives to chemical control. However, potential inte

  12. [The species composition of mosquitoes and ticks in Armenia].

    Science.gov (United States)

    Manukian, D V; Oganesian, A S; Shakhnazarian, S A; Aleksanian, Iu T

    2006-01-01

    Comprehensive epidemiological, entomological, virological, and parasitological studies were conducted to examine the species composition and size of bloodsucking arthropoda (mosquitoes and ticks). A total of 64,567 mosquitoes and 45,180 Ixodes ticks were collected. Among the mosquitoes, Anopheles maculipennis was a prevalent species (81.6%). In all climatic zones, Dermacentor marginatus was the largest in number and most abundant during flag collections from cattle and plants (62.5% and 95.5%, respectively). Virological studies of the collected field material identified 125 strains of arboviruses belonging to 10 viruses: Tyaginya, Sindbis, Batai, Dkhori, tick-borne encephalitis, West Nile fever, Tamdy, KGL, Geta, and Bkhandzha. The identified arboviruses are environmentally associated with both mosquitoes and ticks. The larger number and diversity of bloodsucking artropoda present a potential risk of outbursts of arbovirus infections on the territory of the republic.

  13. Simple intervention to reduce mosquito breeding in waste stabilisation ponds

    DEFF Research Database (Denmark)

    Ensink, Jeroen H J; Mukhtar, Muhammad; van der Hoek, Wim;

    2007-01-01

    Waste stabilisation ponds (WSP) are the preferred method for treatment of urban wastewater in low-income countries but, especially in arid regions, the pond systems can be important breeding sites for mosquitoes of medical importance. In a WSP system in Faisalabad, Pakistan, we assessed the impact...... of simple environmental interventions on mosquito occurrence and abundance. Reducing the amount of floating matter in the ponds, eliminating emergent vegetation and repairing cracks in the cement structure reduced the number of mosquito-positive samples in the intervention ponds to almost zero, whereas...... the control ponds had a significant number of positive samples. This suggests that a combination of simple low-cost interventions is a feasible environmental management strategy for vector control in WSP systems that are located in areas where medically important mosquitoes may breed in the shallow ponds....

  14. Differential equations models for interacting wild and transgenic mosquito populations.

    Science.gov (United States)

    Li, Jia

    2008-07-01

    We formulate and study continuous-time models, based on systems of ordinary differential equations, for interacting wild and transgenic mosquito populations. We assume that the mosquito mating rate is either constant, proportional to total mosquito population size, or has a Holling-II-type functional form. The focus is on the model with the Holling-II-type functional mating rate that incorporates Allee effects, in order to account for mating difficulty when the size of the total mosquito populations is small. We investigate the existence and stability of both boundary and positive equilibria. We show that the Holling-II-type model is the more realistic and, by means of numerical simulations, that it exhibits richer dynamics.

  15. Common Culex Mosquitoes Don't Transmit Zika Virus

    Science.gov (United States)

    ... 161186.html Common Culex Mosquitoes Don't Transmit Zika Virus: Study These widespread insects do spread West Nile ... t appear to be able to transmit the Zika virus to people, researchers report. The researchers at Kansas ...

  16. Biological Control of Mosquito Vectors: Past, Present, and Future

    Science.gov (United States)

    Benelli, Giovanni; Jeffries, Claire L.; Walker, Thomas

    2016-01-01

    Mosquitoes represent the major arthropod vectors of human disease worldwide transmitting malaria, lymphatic filariasis, and arboviruses such as dengue virus and Zika virus. Unfortunately, no treatment (in the form of vaccines or drugs) is available for most of these diseases and vector control is still the main form of prevention. The limitations of traditional insecticide-based strategies, particularly the development of insecticide resistance, have resulted in significant efforts to develop alternative eco-friendly methods. Biocontrol strategies aim to be sustainable and target a range of different mosquito species to reduce the current reliance on insecticide-based mosquito control. In this review, we outline non-insecticide based strategies that have been implemented or are currently being tested. We also highlight the use of mosquito behavioural knowledge that can be exploited for control strategies. PMID:27706105

  17. Salivary Biomarkers in the Control of Mosquito-Borne Diseases

    Directory of Open Access Journals (Sweden)

    Souleymane Doucoure

    2015-11-01

    Full Text Available Vector control remains the most effective measure to prevent the transmission of mosquito-borne diseases. However, the classical entomo-parasitological methods used to evaluate the human exposure to mosquito bites and the effectiveness of control strategies are indirect, labor intensive, and lack sensitivity in low exposure/transmission areas. Therefore, they are limited in their accuracy and widespread use. Studying the human antibody response against the mosquito salivary proteins has provided new biomarkers for a direct and accurate evaluation of the human exposure to mosquito bites, at community and individual levels. In this review, we discuss the development, applications and limits of these biomarkers applied to Aedes- and Anopheles-borne diseases.

  18. Exploiting Intimate Relationships: Controlling Mosquito-Transmitted Disease with Wolbachia.

    Science.gov (United States)

    Caragata, Eric P; Dutra, Heverton L C; Moreira, Luciano A

    2016-03-01

    Mosquito-transmitted diseases impose a growing burden on human health, and current control strategies have proven insufficient to stem the tide. The bacterium Wolbachia is a novel and promising form of control for mosquito-transmitted disease. It manipulates host biology, restricts infection with dengue and other pathogens, and alters host reproduction to promote rapid spread in the field. In this review, we examine how the intimate and diverse relationships formed between Wolbachia and their mosquito hosts can be exploited for disease control purposes. We consider these relationships in the context of recent developments, including successful field trials with Wolbachia-infected mosquitoes to combat dengue, and new Wolbachia infections in key malaria vectors, which have enhanced the disease control prospects of this unique bacterium.

  19. Oviposition and olfaction responses of Aedes aegypti mosquitoes to insecticides.

    Science.gov (United States)

    Canyon, D V; Muller, R

    2013-12-01

    Insecticide applications are not particularly effective on Aedes aegypti mosquitoes which has been attributed to their 'closet' behaviour, or ability to rest in places that remain unexposed to insecticides. Some researchers have suggested that insecticides repel mosquitoes, which would result in less exposure and increased dispersal. If repellence due to insecticides is a fact, acquiring a vector-borne disease, such as dengue, could legitimately be attributed to local vector control efforts and this would lead to restitution claims. This study thus investigated the effect of insecticide presence on mosquito behaviour indirectly via oviposition and directly via olfactory response. In all experiments, oviposition in each insecticide compared to its water and ethanol controls was not significantly different. This indicates that Ae. aegypti mosquitoes are not affected by insecticide presence and that increased dispersal is unlikely to be caused by vector control spraying.

  20. A global assembly of adult female mosquito mark-release-recapture data to inform the control of mosquito-borne pathogens

    NARCIS (Netherlands)

    Guerra, C.A.; Reiner Jr, R.C.; Perkins, T.A.; Lindsay, S.W.; Midega, J.T.; Brady, O.J.; Barker, C.M.; Reisen, W.K.; Harrington, L.C.; Takken, W.; Kitron, U.; Lloyd, A.L.; Hay, S.I.; Scott, T.W.; Smith, D.L.

    2014-01-01

    Background Pathogen transmission by mosquitos is known to be highly sensitive to mosquito bionomic parameters. Mosquito mark-release-recapture (MMRR) experiments are a standard method for estimating such parameters including dispersal, population size and density, survival, blood feeding frequency a

  1. Mosquito larvicidal potential of four common medicinal plants of India

    OpenAIRE

    Anjali Rawani; Anupam Ghosh; Goutam Chandra

    2014-01-01

    Background & objectives: Mosquitoes transmit serious human health diseases, causing millions of deaths every year. Plants may be sources of alternative mosquito control agents. The present study was carried out to assess the role of larvicidal activities of the crude extracts of four plants viz. Alternanthera sessilis L. (Amaranthaceae), Trema orientalis L. (Cannabaceae), Gardenia carinata Smith. (Rubiaceae) and Ruellia tuberosa L. (Acanthaceae) against Culex quinquefasciatus Say in laborator...

  2. Mosquitoes (Diptera: Culicidae) Captured in the Iquitos Area of Peru

    Science.gov (United States)

    1993-01-01

    1991 at three sylvan sites near tl ing arboviruses have been reported: Mayaro , quitos, Department of Loreto, Peru. Situatu on Oropouche, Guama... virus isolation was begun in 1988. within Iquitos. This report deals specifically with the capture Mosquito Collections. In total, eight different...Lima for virus isolation. Mos- groups of mosquitoes not identifiable to the spe- quitoes were identified to species using several cies level because of

  3. Nature or nurture in mosquito resistance to malaria?

    OpenAIRE

    Hurd, Hilary

    2007-01-01

    The genetic basis of mosquito resistance to malaria parasites is well established and currently receives a lot of attention. However this is not the sole determinant of the success or failure of an infection. In a recent article, Lambrechts and colleagues report the influence of the quality of the external environment of a mosquito on infection. They indicate that external variations could substantially reduce the importance of resistance genes in determining infection by malaria parasites. F...

  4. Culex mosquitoes are experimentally unable to transmit Zika virus

    Science.gov (United States)

    Amraoui, Fadila; Atyame-Nten, Célestine; Vega-Rúa, Anubis; Lourenço-de-Oliveira, Ricardo; Vazeille, Marie; Failloux, Anna Bella

    2016-01-01

    We report that two laboratory colonies of Culex quinquefasciatus and Culex pipiens mosquitoes were experimentally unable to transmit ZIKV either up to 21 days post an infectious blood meal or up to 14 days post intrathoracic inoculation. Infectious viral particles were detected in bodies, heads or saliva by a plaque forming unit assay on Vero cells. We therefore consider it unlikely that Culex mosquitoes are involved in the rapid spread of ZIKV. PMID:27605159

  5. Malaria infected mosquitoes express enhanced attraction to human odor.

    Directory of Open Access Journals (Sweden)

    Renate C Smallegange

    Full Text Available There is much evidence that some pathogens manipulate the behaviour of their mosquito hosts to enhance pathogen transmission. However, it is unknown whether this phenomenon exists in the interaction of Anopheles gambiae sensu stricto with the malaria parasite, Plasmodium falciparum--one of the most important interactions in the context of humanity, with malaria causing over 200 million human cases and over 770 thousand deaths each year. Here we demonstrate, for the first time, that infection with P. falciparum causes alterations in behavioural responses to host-derived olfactory stimuli in host-seeking female An. gambiae s.s. mosquitoes. In behavioural experiments we showed that P. falciparum-infected An. gambiae mosquitoes were significantly more attracted to human odors than uninfected mosquitoes. Both P. falciparum-infected and uninfected mosquitoes landed significantly more on a substrate emanating human skin odor compared to a clean substrate. However, significantly more infected mosquitoes landed and probed on a substrate emanating human skin odor than uninfected mosquitoes. This is the first demonstration of a change of An. gambiae behaviour in response to olfactory stimuli caused by infection with P. falciparum. The results of our study provide vital information that could be used to provide better predictions of how malaria is transmitted from human being to human being by An. gambiae s.s. females. Additionally, it highlights the urgent need to investigate this interaction further to determine the olfactory mechanisms that underlie the differential behavioural responses. In doing so, new attractive compounds could be identified which could be used to develop improved mosquito traps for surveillance or trapping programmes that may even specifically target P. falciparum-infected An. gambiae s.s. females.

  6. Mosquito vectors and the spread of cancer: an overlooked connection?

    Science.gov (United States)

    Benelli, Giovanni; Lo Iacono, Annalisa; Canale, Angelo; Mehlhorn, Heinz

    2016-06-01

    Mosquitoes (Diptera: Culicidae) represent a key threat for millions of humans and animals worldwide, vectoring important pathogens and parasites, including malaria, dengue, filariasis, and Zika virus. Besides mosquito-borne diseases, cancers figure among the leading causes of mortality worldwide. It is expected that annual cancer cases will rise from 14 million in 2012 to 22 million within the next two decades. Notably, there are few contrasting evidences of the relationship between cancer and mosquito-borne diseases, with special reference to malaria. However, analogies at the cellular level for the two diseases were reported. Recently, a significant association of malaria incidence with all cancer mortality in 50 USA states was highlighted and may be explained by the ability of Plasmodium to induce suppression of the immune system. However, it was hypothesized that Anopheles vectors may transmit obscure viruses linked with cancer development. The possible activation of cancer pathways by mosquito feeding events is not rare. For instance, the hamster reticulum cell sarcoma can be transmitted through the bites of Aedes aegypti by a transfer of tumor cells. Furthermore, mosquito bites may influence human metabolic pathways following different mechanisms, leading to other viral infections and/or oncogenesis. Hypersensitivity to mosquito bites is routed by a unique pathogenic mechanism linking Epstein-Barr virus infection, allergy, and oncogenesis. During dengue virus infection, high viral titers, macrophage infiltration, and tumor necrosis factor alpha production in the local tissues are the three key important events that lead to hemorrhage. Overall, basic epidemiological knowledge on the relationships occurring between mosquito vector activity and the spread of cancer is urgently needed, as well as detailed information about the ability of Culicidae to transfer viruses or tumor cells among hosts over time. Current evidences on nanodrugs with multipotency against

  7. Toxic effect of blood feeding in male mosquitoes

    Directory of Open Access Journals (Sweden)

    Mahmood R Nikbakhtzadeh

    2016-01-01

    Full Text Available Blood- and sugar feeding of female mosquitoes has been frequently observed in the laboratory and in the field, but only sugar feeding of males has been reported. Here, we describe for the first time that Culex quinquefasciatus males feed on blood as well. Blood feeding easily happened on a blood-soaked cotton roll and, to a lesser extent, through a thin artificial layer. Mating history of a male specimen does not affect his blood feeding behavior. Male mosquitoes feed on blood even when they have a readily available sugar source. Nevertheless, feeding on blood reduces the survival rate of males to just a few days, as compared to more than a month for mosquitoes fed only on sugar. Comparing survival of male mosquitoes fed on blood only, sugar only, and a combination of both clearly demonstrated that mortality is not affected by malnutrition (reduced sugar levels, but rather due to ingested blood. On average male mosquitoes ingested ca. 0.5 µl of blood, i.e., about 10% of the amount of blood ingested by an engorged female. Although this unexpected observation of blood feeding in the laboratory by male mosquitoes is interesting, structural impairment prevents male feeding on vertebrate blood. In agreement with the literature, male and female proboscises and stylets were in general of similar size, but male mandibles were significantly shorter than female counterparts, thus explaining their inability to pierce through skin layers.

  8. New host and distribution for the mosquito parasite Strelkovimermis spiculatus

    Directory of Open Access Journals (Sweden)

    ROCIO P. LOPEZ

    2016-01-01

    Full Text Available Strelkovimermis spiculatus , Poinar & Camino 1986 (Nematoda: Mer - mithidae ha sido encontrado parasitando algunos géneros de mosquitos tales como Aedes ( Ochlerotatus , Culex y Psorophora. En un proyecto sobre distribución de mosquitos en la Provincia de Buenos Aires, Argentina, fueron encontradas especies de mosquitos parasitadas por nematodos en criaderos naturales, en los alrededores de la ciudad de Mar del Plata. El objetivo de este trabajo es identificar este parási - to detectado en esta área de distribución y determinar las especies de mosquitos hospedadoras. Se describe la utilidad de secuencias correspondientes a los genes COI y 18S RNAr-ITS1-5.8S RNAr-ITS2-28S RNAr, en la identificación molecular de este nematodo, como complemento de la identificación de acuerdo con caracteres morfológicos, confirmando la identidad de S. spiculatus. En este trabajo se describe por primera vez a este nematodo infestando larvas de Culex eduardoi en un criadero natural de mosquitos, registrando la expansión de la distribución sudeste de este agente de control biológico de poblaciones de mosquitos de importancia sanitaria.

  9. Composition of human skin microbiota affects attractiveness to malaria mosquitoes.

    Directory of Open Access Journals (Sweden)

    Niels O Verhulst

    Full Text Available The African malaria mosquito Anopheles gambiae sensu stricto continues to play an important role in malaria transmission, which is aggravated by its high degree of anthropophily, making it among the foremost vectors of this disease. In the current study we set out to unravel the strong association between this mosquito species and human beings, as it is determined by odorant cues derived from the human skin. Microbial communities on the skin play key roles in the production of human body odour. We demonstrate that the composition of the skin microbiota affects the degree of attractiveness of human beings to this mosquito species. Bacterial plate counts and 16S rRNA sequencing revealed that individuals that are highly attractive to An. gambiae s.s. have a significantly higher abundance, but lower diversity of bacteria on their skin than individuals that are poorly attractive. Bacterial genera that are correlated with the relative degree of attractiveness to mosquitoes were identified. The discovery of the connection between skin microbial populations and attractiveness to mosquitoes may lead to the development of new mosquito attractants and personalized methods for protection against vectors of malaria and other infectious diseases.

  10. Discovery of mosquito saliva microRNAs during CHIKV infection.

    Science.gov (United States)

    Maharaj, Payal D; Widen, Steven G; Huang, Jing; Wood, Thomas G; Thangamani, Saravanan

    2015-01-01

    Mosquito borne pathogens are transmitted to humans via saliva during blood feeding. Mosquito saliva is a complex concoction of many secretory factors that modulate the feeding foci to enhance pathogen infection and establishment. Multiple salivary proteins/factors have been identified/characterized that enhance pathogen infection. Here, we describe, for the first time, the identification of exogenous microRNAs from mosquito saliva. MicroRNAs are short, 18-24 nucleotide, non-coding RNAs that regulate gene expression, and are generally intracellular. However, circulating miRNAs have been described from serum and saliva of humans. Exogenous miRNAs have not been reported from hematophagous arthropod saliva. We sought to identify miRNAs in the mosquito saliva and their role in Chikungunya virus (CHIKV) infection. Next generation sequencing was utilized to identify 103 exogenous miRNAs in mosquito saliva of which 31 miRNAs were previously unidentified and were designated novel. Several miRNAs that we have identified are expressed only in the CHIKV infected mosquitoes. Five of the saliva miRNAs were tested for their potential to regulated CHIKV infection, and our results demonstrate their functional role in the transmission and establishment of infection during blood feeding on the host.

  11. Mosquito surveillance for prevention and control of emerging mosquito-borne diseases in Portugal - 2008-2014.

    Science.gov (United States)

    Osório, Hugo C; Zé-Zé, Líbia; Amaro, Fátima; Alves, Maria J

    2014-11-12

    Mosquito surveillance in Europe is essential for early detection of invasive species with public health importance and prevention and control of emerging pathogens. In Portugal, a vector surveillance national program-REVIVE (REde de VIgilância de VEctores)-has been operating since 2008 under the custody of Portuguese Ministry of Health. The REVIVE is responsible for the nationwide surveillance of hematophagous arthropods. Surveillance for West Nile virus (WNV) and other flaviviruses in adult mosquitoes is continuously performed. Adult mosquitoes-collected mainly with Centre for Disease Control light traps baited with CO2-and larvae were systematically collected from a wide range of habitats in 20 subregions (NUTS III). Around 500,000 mosquitoes were trapped in more than 3,000 trap nights and 3,500 positive larvae surveys, in which 24 species were recorded. The viral activity detected in mosquito populations in these years has been limited to insect specific flaviviruses (ISFs) non-pathogenic to humans. Rather than emergency response, REVIVE allows timely detection of changes in abundance and species diversity providing valuable knowledge to health authorities, which may take control measures of vector populations reducing its impact on public health. This work aims to present the REVIVE operation and to expose data regarding mosquito species composition and detected ISFs.

  12. New technique to count mosquito adults: using ImageJ software to estimate number of mosquito adults in a trap.

    Science.gov (United States)

    Kesavaraju, Banugopan; Dickson, Sammie

    2012-12-01

    A new technique is described here to count mosquitoes using open-source software. We wanted to develop a protocol that would estimate the total number of mosquitoes from a picture using ImageJ. Adult mosquitoes from CO2-baited traps were spread on a tray and photographed. The total number of mosquitoes in a picture was estimated using various calibrations on ImageJ, and results were compared with manual counting to identify the ideal calibration. The average trap count was 1,541, and the average difference between the manual count and the best calibration was 174.11 +/- 21.59, with 93% correlation. Subsequently, contents of a trap were photographed 5 different times after they were shuffled between each picture to alter the picture pattern of adult mosquitoes. The standard error among variations stayed below 50, indicating limited variation for total count between pictures of the same trap when the pictures were processed through ImageJ. These results indicate the software could be utilized efficiently to estimate total number of mosquitoes from traps.

  13. Mosquito host selection varies seasonally with host availability and mosquito density.

    Directory of Open Access Journals (Sweden)

    Tara C Thiemann

    2011-12-01

    Full Text Available Host selection by vector mosquitoes is a critical component of virus proliferation, particularly for viruses such as West Nile (WNV that are transmitted enzootically to a variety of avian hosts, and tangentially to dead-end hosts such as humans. Culex tarsalis is a principal vector of WNV in rural areas of western North America. Based on previous work, Cx. tarsalis utilizes a variety of avian and mammalian hosts and tends to feed more frequently on mammals in the late summer than during the rest of the year. To further explore this and other temporal changes in host selection, bloodfed females were collected at a rural farmstead and heron nesting site in Northern California from May 2008 through May 2009, and bloodmeal hosts identified using either a microsphere-based array or by sequencing of the mitochondrial cytochrome c oxidase I (COI gene. Host composition during summer was dominated by four species of nesting Ardeidae. In addition, the site was populated with various passerine species as well as domestic farm animals and humans. When present, Cx. tarsalis fed predominantly (>80% upon the ardeids, with Black-crowned Night-Herons, a highly competent WNV host, the most prevalent summer host. As the ardeids fledged and left the area and mosquito abundance increased in late summer, Cx. tarsalis feeding shifted to include more mammals, primarily cattle, and a high diversity of avian species. In the winter, Yellow-billed Magpies and House Sparrows were the predominant hosts, and Yellow-billed Magpies and American Robins were fed upon more frequently than expected given their relative abundance. These data demonstrated that host selection was likely based both on host availability and differences in utilization, that the shift of bloodfeeding to include more mammalian hosts was likely the result of both host availability and increased mosquito abundance, and that WNV-competent hosts were fed upon by Cx. tarsalis throughout the year.

  14. · RESSENYA A Andar 1km en línea recta. La cárcel del siglo XXI que vive el preso, de Manuel Gallego, Pedro J. Cabrera, Julián C. Ríos i José Luis Segovia

    Directory of Open Access Journals (Sweden)

    Pamela Wulf Leal

    2011-09-01

    Full Text Available Andar 1km en línea recta en realitat pertany a una obra més àmplia dels seus autors que ja té un recorregut important en la sociologia de la pena a Espanya.Si bé un dels temes sempre pendents en l'estudi de les presons és veure quina és la realitat, com es viu la quotidianitat, des de les ja conegudes Mil voces presas i Mirando al abismo, aquesta visió sociològica, i no merament normativa de la presó, expressa un coneixement que no pot passar desapercebut.Aquest nou treball constitueix l'actualització d'aquestes investigacions anteriors, en el qual l'enquesta a persones preses constitueix la seva base empírica fonamental amb una mostra final integrada per 1.668 qüestionaris vàlids, que representa la més nombrosa mai aconseguida en els estudis penitenciaris realitzats a Espanya. Aquesta investigació permet obtenir una visió explicada pels propis protagonistes del tancament, que s'apropa al que realment ocorre a l'interior de les presons a través dels seus relats.

  15. Targeting male mosquito swarms to control malaria vector density

    Science.gov (United States)

    Sawadogo, Simon Peguedwinde; Niang, Abdoulaye; Bilgo, Etienne; Millogo, Azize; Maïga, Hamidou; Dabire, Roch K.; Tripet, Frederic; Diabaté, Abdoulaye

    2017-01-01

    Malaria control programs are being jeopardized by the spread of insecticide resistance in mosquito vector populations. It has been estimated that the spread of resistance could lead to an additional 120000 deaths per year, and interfere with the prospects for sustained control or the feasibility of achieving malaria elimination. Another complication for the development of resistance management strategies is that, in addition to insecticide resistance, mosquito behavior evolves in a manner that diminishes the impact of LLINs and IRS. Mosquitoes may circumvent LLIN and IRS control through preferential feeding and resting outside human houses and/or being active earlier in the evening before people go to sleep. Recent developments in our understanding of mosquito swarming suggest that new tools targeting mosquito swarms can be designed to cut down the high reproductive rate of malaria vectors. Targeting swarms of major malaria vectors may provide an effective control method to counteract behavioral resistance developed by mosquitoes. Here, we evaluated the impact of systematic spraying of swarms of Anopheles gambiae s.l. using a mixed carbamate and pyrethroid aerosol. The impact of this intervention on vector density, female insemination rates and the age structure of males was measured. We showed that the resulting mass killing of swarming males and some mate-seeking females resulted in a dramatic 80% decrease in population size compared to a control population. A significant decrease in female insemination rate and a significant shift in the age structure of the male population towards younger males incapable of mating were observed. This paradigm-shift study therefore demonstrates that targeting primarily males rather than females, can have a drastic impact on mosquito population. PMID:28278212

  16. Analyzing mosquito (Diptera: culicidae diversity in Pakistan by DNA barcoding.

    Directory of Open Access Journals (Sweden)

    Muhammad Ashfaq

    Full Text Available BACKGROUND: Although they are important disease vectors mosquito biodiversity in Pakistan is poorly known. Recent epidemics of dengue fever have revealed the need for more detailed understanding of the diversity and distributions of mosquito species in this region. DNA barcoding improves the accuracy of mosquito inventories because morphological differences between many species are subtle, leading to misidentifications. METHODOLOGY/PRINCIPAL FINDINGS: Sequence variation in the barcode region of the mitochondrial COI gene was used to identify mosquito species, reveal genetic diversity, and map the distribution of the dengue-vector species in Pakistan. Analysis of 1684 mosquitoes from 491 sites in Punjab and Khyber Pakhtunkhwa during 2010-2013 revealed 32 species with the assemblage dominated by Culex quinquefasciatus (61% of the collection. The genus Aedes (Stegomyia comprised 15% of the specimens, and was represented by six taxa with the two dengue vector species, Ae. albopictus and Ae. aegypti, dominant and broadly distributed. Anopheles made up another 6% of the catch with An. subpictus dominating. Barcode sequence divergence in conspecific specimens ranged from 0-2.4%, while congeneric species showed from 2.3-17.8% divergence. A global haplotype analysis of disease-vectors showed the presence of multiple haplotypes, although a single haplotype of each dengue-vector species was dominant in most countries. Geographic distribution of Ae. aegypti and Ae. albopictus showed the later species was dominant and found in both rural and urban environments. CONCLUSIONS: As the first DNA-based analysis of mosquitoes in Pakistan, this study has begun the construction of a barcode reference library for the mosquitoes of this region. Levels of genetic diversity varied among species. Because of its capacity to differentiate species, even those with subtle morphological differences, DNA barcoding aids accurate tracking of vector populations.

  17. Response of the mosquito protein interaction network to dengue infection

    Directory of Open Access Journals (Sweden)

    Pike Andrew D

    2010-06-01

    Full Text Available Abstract Background Two fifths of the world's population is at risk from dengue. The absence of effective drugs and vaccines leaves vector control as the primary intervention tool. Understanding dengue virus (DENV host interactions is essential for the development of novel control strategies. The availability of genome sequences for both human and mosquito host greatly facilitates genome-wide studies of DENV-host interactions. Results We developed the first draft of the mosquito protein interaction network using a computational approach. The weighted network includes 4,214 Aedes aegypti proteins with 10,209 interactions, among which 3,500 proteins are connected into an interconnected scale-free network. We demonstrated the application of this network for the further annotation of mosquito proteins and dissection of pathway crosstalk. Using three datasets based on physical interaction assays, genome-wide RNA interference (RNAi screens and microarray assays, we identified 714 putative DENV-associated mosquito proteins. An integrated analysis of these proteins in the network highlighted four regions consisting of highly interconnected proteins with closely related functions in each of replication/transcription/translation (RTT, immunity, transport and metabolism. Putative DENV-associated proteins were further selected for validation by RNAi-mediated gene silencing, and dengue viral titer in mosquito midguts was significantly reduced for five out of ten (50.0% randomly selected genes. Conclusions Our results indicate the presence of common host requirements for DENV in mosquitoes and humans. We discuss the significance of our findings for pharmacological intervention and genetic modification of mosquitoes for blocking dengue transmission.

  18. A spatial model of mosquito host-seeking behavior.

    Directory of Open Access Journals (Sweden)

    Bree Cummins

    Full Text Available Mosquito host-seeking behavior and heterogeneity in host distribution are important factors in predicting the transmission dynamics of mosquito-borne infections such as dengue fever, malaria, chikungunya, and West Nile virus. We develop and analyze a new mathematical model to describe the effect of spatial heterogeneity on the contact rate between mosquito vectors and hosts. The model includes odor plumes generated by spatially distributed hosts, wind velocity, and mosquito behavior based on both the prevailing wind and the odor plume. On a spatial scale of meters and a time scale of minutes, we compare the effectiveness of different plume-finding and plume-tracking strategies that mosquitoes could use to locate a host. The results show that two different models of chemotaxis are capable of producing comparable results given appropriate parameter choices and that host finding is optimized by a strategy of flying across the wind until the odor plume is intercepted. We also assess the impact of changing the level of host aggregation on mosquito host-finding success near the end of the host-seeking flight. When clusters of hosts are more tightly associated on smaller patches, the odor plume is narrower and the biting rate per host is decreased. For two host groups of unequal number but equal spatial density, the biting rate per host is lower in the group with more individuals, indicative of an attack abatement effect of host aggregation. We discuss how this approach could assist parameter choices in compartmental models that do not explicitly model the spatial arrangement of individuals and how the model could address larger spatial scales and other probability models for mosquito behavior, such as Lévy distributions.

  19. West Nile virus in Tunisia, 2014: First isolation from mosquitoes.

    Science.gov (United States)

    Wasfi, F; Dachraoui, K; Cherni, S; Bosworth, A; Barhoumi, W; Dowall, S; Chelbi, I; Derbali, M; Zoghlami, Z; Beier, J C; Zhioua, E

    2016-07-01

    Several outbreaks of human West Nile virus (WNV) infections were reported in Tunisia during the last two decades. Serological studies on humans as well as on equine showed intensive circulation of WNV in Tunisia. However, no virus screening of mosquitoes for WNV has been performed in Tunisia. In the present study, we collected mosquito samples from Central Tunisia to be examined for the presence of flaviviruses. A total of 102 Culex pipiens mosquitoes were collected in September 2014 from Central Tunisia. Mosquitoes were pooled according to the collection site, date and sex with a maximum of 5 specimens per pool and tested for the presence of flaviviruses by conventional reverse transcription heminested PCR and by a specific West Nile virus real time reverse transcription PCR. Of a total of 21 pools tested, 7 were positive for WNV and no other flavivirus could be evidenced in mosquito pools. In addition, WNV was isolated on Vero cells. Phylogenetic analysis showed that recent Tunisian WNV strains belong to lineage 1 WNV and are closely related to the Tunisian strain 1997 (PAH 001). This is the first detection and isolation of WNV from mosquitoes in Tunisia. Some areas of Tunisia are at high risk for human WNV infections. WNV is likely to cause future sporadic and foreseeable outbreaks. Therefore, it is of major epidemiological importance to set up an entomological surveillance as an early alert system. Timely detection of WNV should prompt vector control to prevent future outbreaks. In addition, education of people to protect themselves from mosquito bites is of major epidemiological importance as preventive measure against WNV infection.

  20. Wolbachia Modulates Lipid Metabolism in Aedes albopictus Mosquito Cells

    Science.gov (United States)

    Molloy, Jennifer C.; Sommer, Ulf; Viant, Mark R.

    2016-01-01

    ABSTRACT Certain strains of the intracellular endosymbiont Wolbachia can strongly inhibit or block the transmission of viruses such as dengue virus (DENV) by Aedes mosquitoes, and the mechanisms responsible are still not well understood. Direct infusion and liquid chromatography-Fourier transform ion cyclotron resonance (FT-ICR) mass spectrometry-based lipidomics analyses were conducted using Aedes albopictus Aa23 cells that were infected with the wMel and wMelPop strains of Wolbachia in comparison to uninfected Aa23-T cells. Substantial shifts in the cellular lipid profile were apparent in the presence of Wolbachia. Most significantly, almost all sphingolipid classes were depleted, and some reductions in diacylglycerols and phosphatidylcholines were also observed. These lipid classes have previously been shown to be selectively enriched in DENV-infected mosquito cells, suggesting that Wolbachia may produce a cellular lipid environment that is antagonistic to viral replication. The data improve our understanding of the intracellular interactions between Wolbachia and mosquitoes. IMPORTANCE Mosquitoes transmit a variety of important viruses to humans, such as dengue virus and Zika virus. Certain strains of the intracellular bacterial genus called Wolbachia found in or introduced into mosquitoes can block the transmission of viruses, including dengue virus, but the mechanisms responsible are not well understood. We found substantial shifts in the cellular lipid profiles in the presence of these bacteria. Some lipid classes previously shown to be enriched in dengue virus-infected mosquito cells were depleted in the presence of Wolbachia, suggesting that Wolbachia may produce a cellular lipid environment that inhibits mosquito-borne viruses. PMID:26994075

  1. Determinants of Arbovirus Vertical Transmission in Mosquitoes.

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    Sebastian Lequime

    2016-05-01

    Full Text Available Vertical transmission (VT and horizontal transmission (HT of pathogens refer to parental and non-parental chains of host-to-host transmission. Combining HT with VT enlarges considerably the range of ecological conditions in which a pathogen can persist, but the factors governing the relative frequency of each transmission mode are poorly understood for pathogens with mixed-mode transmission. Elucidating these factors is particularly important for understanding the epidemiology of arthropod-borne viruses (arboviruses of public health significance. Arboviruses are primarily maintained by HT between arthropod vectors and vertebrate hosts in nature, but are occasionally transmitted vertically in the vector population from an infected female to her offspring, which is a proposed maintenance mechanism during adverse conditions for HT. Here, we review over a century of published primary literature on natural and experimental VT, which we previously assembled into large databases, to identify biological factors associated with the efficiency of arbovirus VT in mosquito vectors. Using a robust statistical framework, we highlight a suite of environmental, taxonomic, and physiological predictors of arbovirus VT. These novel insights contribute to refine our understanding of strategies employed by arboviruses to persist in the environment and cause substantial public health concern. They also provide hypotheses on the biological processes underlying the relative VT frequency for pathogens with mixed-mode transmission that can be tested empirically.

  2. Determinants of Arbovirus Vertical Transmission in Mosquitoes.

    Science.gov (United States)

    Lequime, Sebastian; Paul, Richard E; Lambrechts, Louis

    2016-05-01

    Vertical transmission (VT) and horizontal transmission (HT) of pathogens refer to parental and non-parental chains of host-to-host transmission. Combining HT with VT enlarges considerably the range of ecological conditions in which a pathogen can persist, but the factors governing the relative frequency of each transmission mode are poorly understood for pathogens with mixed-mode transmission. Elucidating these factors is particularly important for understanding the epidemiology of arthropod-borne viruses (arboviruses) of public health significance. Arboviruses are primarily maintained by HT between arthropod vectors and vertebrate hosts in nature, but are occasionally transmitted vertically in the vector population from an infected female to her offspring, which is a proposed maintenance mechanism during adverse conditions for HT. Here, we review over a century of published primary literature on natural and experimental VT, which we previously assembled into large databases, to identify biological factors associated with the efficiency of arbovirus VT in mosquito vectors. Using a robust statistical framework, we highlight a suite of environmental, taxonomic, and physiological predictors of arbovirus VT. These novel insights contribute to refine our understanding of strategies employed by arboviruses to persist in the environment and cause substantial public health concern. They also provide hypotheses on the biological processes underlying the relative VT frequency for pathogens with mixed-mode transmission that can be tested empirically.

  3. Register for September 20 Webinar on Protecting Students from Mosquitoes & Zika Virus at School

    Science.gov (United States)

    EPA’s Center of Expertise for School IPM will offer a webinar titled Protecting Students from Mosquitoes & Zika Virus at School. Mosquito-borne diseases have been responsible for much suffering throughout human history.

  4. Adulticidal & larvicidal efficacy of three neonicotinoids against insecticide susceptible & resistant mosquito strains

    Directory of Open Access Journals (Sweden)

    Sreehari Uragayala

    2015-01-01

    Interpretation & conclusions: The present study indicated that insecticide resistant strains of mosquito species tested showed more susceptibility to the three neonicotinoids tested, and the possibility of using neonicotinoids for the control of resistant mosquitoes should be explored.

  5. Virus-derived DNA drives mosquito vector tolerance to arboviral infection

    Science.gov (United States)

    Goic, Bertsy; Stapleford, Kenneth A.; Frangeul, Lionel; Doucet, Aurélien J.; Gausson, Valérie; Blanc, Hervé; Schemmel-Jofre, Nidia; Cristofari, Gael; Lambrechts, Louis; Vignuzzi, Marco; Saleh, Maria-Carla

    2016-01-01

    Mosquitoes develop long-lasting viral infections without substantial deleterious effects, despite high viral loads. This makes mosquitoes efficient vectors for emerging viral diseases with enormous burden on public health. How mosquitoes resist and/or tolerate these viruses is poorly understood. Here we show that two species of Aedes mosquitoes infected with two arboviruses from distinct families (dengue or chikungunya) generate a viral-derived DNA (vDNA) that is essential for mosquito survival and viral tolerance. Inhibition of vDNA formation leads to extreme susceptibility to viral infections, reduction of viral small RNAs due to an impaired immune response, and loss of viral tolerance. Our results highlight an essential role of vDNA in viral tolerance that allows mosquito survival and thus may be important for arbovirus dissemination and transmission. Elucidating the mechanisms of mosquito tolerance to arbovirus infection paves the way to conceptualize new antivectorial strategies to selectively eliminate arbovirus-infected mosquitoes. PMID:27580708

  6. Updated Checklist of the Mosquitoes (Diptera: Culicidae) of French Guiana.

    Science.gov (United States)

    Talaga, Stanislas; Dejean, Alain; Carinci, Romuald; Gaborit, Pascal; Dusfour, Isabelle; Girod, Romain

    2015-09-01

    The incredible mosquito species diversity in the Neotropics can provoke major confusion during vector control programs when precise identification is needed. This is especially true in French Guiana where studies on mosquito diversity practically ceased 35 yr ago. In order to fill this gap, we propose here an updated and comprehensive checklist of the mosquitoes of French Guiana, reflecting the latest changes in classification and geographical distribution and the recognition of current or erroneous synonymies. This work was undertaken in order to help ongoing and future research on mosquitoes in a broad range of disciplines such as ecology, biogeography, and medical entomology. Thirty-two valid species cited in older lists have been removed, and 24 species have been added including 12 species (comprising two new genera and three new subgenera) reported from French Guiana for the first time. New records are from collections conducted on various phytotelmata in French Guiana and include the following species: Onirion sp. cf Harbach and Peyton (2000), Sabethes (Peytonulus) hadrognathus Harbach, Sabethes (Peytonulus) paradoxus Harbach, Sabethes (Peytonulus) soperi Lane and Cerqueira, Sabethes (Sabethinus) idiogenes Harbach, Sabethes (Sabethes) quasicyaneus Peryassú, Runchomyia (Ctenogoeldia) magna (Theobald), Wyeomyia (Caenomyiella) sp. cf Harbach and Peyton (1990), Wyeomyia (Dendromyia) ypsipola Dyar, Wyeomyia (Hystatomyia) lamellata (Bonne-Wepster and Bonne), Wyeomyia (Miamyia) oblita (Lutz), and Toxorhynchites (Lynchiella) guadeloupensis (Dyar and Knab). At this time, the mosquitoes of French Guiana are represented by 235 species distributed across 22 genera, nine tribes, and two subfamilies.

  7. Resource Limitation, Controphic Ostracod Density and Larval Mosquito Development.

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    Raylea Rowbottom

    Full Text Available Aquatic environments can be restricted with the amount of available food resources especially with changes to both abiotic and biotic conditions. Mosquito larvae, in particular, are sensitive to changes in food resources. Resource limitation through inter-, and intra-specific competition among mosquitoes are known to affect both their development and survival. However, much less is understood about the effects of non-culicid controphic competitors (species that share the same trophic level. To address this knowledge gap, we investigated and compared mosquito larval development, survival and adult size in two experiments, one with different densities of non-culicid controphic conditions and the other with altered resource conditions. We used Aedes camptorhynchus, a salt marsh breeding mosquito and a prominent vector for Ross River virus in Australia. Aedes camptorhynchus usually has few competitors due to its halo-tolerance and distribution in salt marshes. However, sympatric ostracod micro-crustaceans often co-occur within these salt marshes and can be found in dense populations, with field evidence suggesting exploitative competition for resources. Our experiments demonstrate resource limiting conditions caused significant increases in mosquito developmental times, decreased adult survival and decreased adult size. Overall, non-culicid exploitation experiments showed little effect on larval development and survival, but similar effects on adult size. We suggest that the alterations of adult traits owing to non-culicid controphic competition has potential to extend to vector-borne disease transmission.

  8. Temporal Coordination of Carbohydrate Metabolism during Mosquito Reproduction.

    Directory of Open Access Journals (Sweden)

    Yuan Hou

    2015-07-01

    Full Text Available Hematophagous mosquitoes serve as vectors of multiple devastating human diseases, and many unique physiological features contribute to the incredible evolutionary success of these insects. These functions place high-energy demands on a reproducing female mosquito, and carbohydrate metabolism (CM must be synchronized with these needs. Functional analysis of metabolic gene profiling showed that major CM pathways, including glycolysis, glycogen and sugar metabolism, and citrate cycle, are dramatically repressed at post eclosion (PE stage in mosquito fat body followed by a sharply increase at post-blood meal (PBM stage, which were also verified by Real-time RT-PCR. Consistent to the change of transcript and protein level of CM genes, the level of glycogen, glucose and trehalose and other secondary metabolites are also periodically accumulated and degraded during the reproductive cycle respectively. Levels of triacylglycerols (TAG, which represent another important energy storage form in the mosquito fat body, followed a similar tendency. On the other hand, ATP, which is generated by catabolism of these secondary metabolites, showed an opposite trend. Additionally, we used RNA interference studies for the juvenile hormone and ecdysone receptors, Met and EcR, coupled with transcriptomics and metabolomics analyses to show that these hormone receptors function as major regulatory switches coordinating CM with the differing energy requirements of the female mosquito throughout its reproductive cycle. Our study demonstrates how, by metabolic reprogramming, a multicellular organism adapts to drastic and rapid functional changes.

  9. Accelerated evolution of constraint elements for hematophagic adaptation in mosquitoes.

    Science.gov (United States)

    Wang, Ming-Shan; Adeola, Adeniyi C; Li, Yan; Zhang, Ya-Ping; Wu, Dong-Dong

    2015-11-18

    Comparative genomics is a powerful approach that comprehensively interprets the genome. Herein, we performed whole genome comparative analysis of 16 Diptera genomes, including four mosquitoes and 12 Drosophilae. We found more than 540 000 constraint elements (CEs) in the Diptera genome, with the majority found in the intergenic, coding and intronic regions. Accelerated elements (AEs) identified in mosquitoes were mostly in the protein-coding regions (>93%), which differs from vertebrates in genomic distribution. Some genes functionally enriched in blood digestion, body temperature regulation and insecticide resistance showed rapid evolution not only in the lineage of the recent common ancestor of mosquitoes (RCAM), but also in some mosquito lineages. This may be associated with lineage-specific traits and/or adaptations in comparison with other insects. Our findings revealed that although universally fast evolution acted on biological systems in RCAM, such as hematophagy, same adaptations also appear to have occurred through distinct degrees of evolution in different mosquito species, enabling them to be successful blood feeders in different environments.

  10. Comparison of adult mosquito community structure on various habitats

    Institute of Scientific and Technical Information of China (English)

    ZHONG-CHENGYAN; HARRYZHONG

    2005-01-01

    The community structure of adult mosquitoes was compared from New Jersey light trap collections in six different types of habitats in Citrus County, Florida, USA. From October 1998 to December 2000, mosquitoes were collected three times a week from the following habitats (swamps, swamps and freshwater marshes, pine fiat-woods, pine fiat-woods and scrub, salt marshes, and salt marshes and mangroves). Mosquito density was highest in the swamps and freshwater marshes habitat, with an average of 95.65 specimens per trap.Density was lowest in the flatwoods and scrub habitat, with an average of 14.38 specimens per trap. Species dominance differed among habitats. Salt marshes produced the greatest aggregation index, while pine flatwoods produced the lowest. Conversely, diversity analysis showed that pine flatwoods had the greatest diversity, while salt marshes the lowest diversity. Similarity indices indicated that the adult mosquito communities from pine flatwoods and pine flatwoods and scrub were very similar (0.8583). The adult mosquito community of salt marshes was different from that of swamps and freshwater marshes (the similar index was 0.0217).

  11. Silica nanoparticle: a potential new insecticide for mosquito vector control.

    Science.gov (United States)

    Barik, Tapan K; Kamaraju, Raghavendra; Gowswami, Arunava

    2012-09-01

    Presently, there is a need for increased efforts to develop newer and effective methods to control mosquito vectors as the existing chemical and biological methods are not as effective as in earlier period owing to different technical and operational reasons. The use of nanomaterial products in various sectors of science including health increased during the last decade. We tested three types of nanosilica, namely lipophilic, hydrophilic and hydrophobic, to assess their larvicidal, pupicidal and growth inhibitor properties and also their influence on oviposition behaviour (attraction/deterrence) of mosquito species that transmit human diseases, namely malaria (Anopheles), yellow fever, chickungunya and dengue (Aedes), lymphatic filariasis and encephalitis (Culex and Aedes). Application of hydrophobic nanosilica at 112.5 ppm was found effective against mosquito species tested. The larvicidal effect of hydrophobic nanosilica on mosquito species tested was in the order of Anopheles stephensi > Aedes aegypti > Culex quinquefasciatus, and the pupicidal effect was in the order of A. stephensi > C. quinquefasciatus > Ae. aegypti. Results of combined treatment of hydrophobic nanosilica with temephos in larvicidal test indicated independent toxic action without any additive effect. This is probably the first report that demonstrated that nanoparticles particularly nanosilica could be used in mosquito vector control.

  12. Toxicity of a plant based mosquito repellent/killer.

    Science.gov (United States)

    Singh, Bhoopendra; Singh, Prakash Raj; Mohanty, Manoj Kumar

    2012-12-01

    The mission to make humans less attractive to mosquitoes has fuelled decades of scientific research on mosquito behaviour and control. The search for the perfect topical insect repellent/killer continues. This analysis was conducted to review and explore the scientific information on toxicity produced by the ingredients/contents of a herbal product. In this process of systemic review the following methodology was applied. By doing a MEDLINE search with key words of selected plants, plant based insect repellents/killers pertinent articles published in journals and authentic books were reviewed. The World Wide Web and the Extension Toxicity Network database (IPCS-ITOX) were also searched for toxicology data and other pertinent information. Repellents do not all share a single mode of action and surprisingly little is known about how repellents act on their target insects. Moreover, different mosquito species may react differently to the same repellent. After analysis of available data and information on the ingredient, of the product in relation to medicinal uses, acute and chronic toxicity of the selected medicinal plants, it can be concluded that the ingredients included in the herbal product can be used as active agents against mosquitoes. If the product which contains the powder of the above said plants is applied with care and safety, it is suitable fo use as a mosquito repellent/killer.

  13. Expression of a mutated phospholipase A2 in transgenic Aedes fluviatilis mosquitoes impacts Plasmodium gallinaceum development

    OpenAIRE

    Rodrigues, F. G.; Santos, M. N.; de Carvalho, T. X. T.; Rocha, B. C.; Riehle, M. A.; Pimenta, P. F. P.; Abraham, E. G.; Jacobs-Lorena, M; Alves de Brito, C. F.; Moreira, L. A

    2008-01-01

    The genetic manipulation of mosquito vectors is an alternative strategy in the fight against malaria. It was previously shown that bee venom phospholipase A2 (PLA2) inhibits ookinete invasion of the mosquito midgut although mosquito fitness was reduced. To maintain the PLA2 blocking ability without compromising mosquito biology, we mutated the protein-coding sequence to inactivate the enzyme while maintaining the protein’s structure. DNA encoding the mutated PLA2 (mPLA2) was placed downstream...

  14. Gene expression patterns and sequence polymorphisms associated with mosquito resistance to Bacillus thuringiensis israelensis toxins

    OpenAIRE

    Després, Laurence; Stalinski, Renaud; Tetreau, Guillaume; Paris, Margot; Bonin, Aurélie; Navratil, Vincent; Reynaud, Stéphane; David, Jean-Philippe

    2014-01-01

    Background Despite the intensive use of Bacillus thuringiensis israelensis (Bti) toxins for mosquito control, little is known about the long term effect of exposure to this cocktail of toxins on target mosquito populations. In contrast to the many cases of resistance to Bacillus thuringiensis Cry toxins observed in other insects, there is no evidence so far for Bti resistance evolution in field mosquito populations. High fitness costs measured in a Bti selected mosquito laboratory strain sugg...

  15. Efficacy of neem chippings for mosquito larval control under field conditions

    OpenAIRE

    Imbahale, Susan S; Mukabana, Wolfgang R

    2015-01-01

    Background An in depth understanding of mosquito breeding biology and factors regulating population sizes is fundamental for vector population control. This paper presents results from a survey of mosquito breeding habitats and the efficacy of neem chippings as a potential larvicide that can be integrated in mosquito control on Nyabondo Plateau in western Kenya. Results Six main mosquito habitat types namely artificial ponds, abandoned fish ponds, active fish ponds, open drains, temporary poo...

  16. Application of biogenic carbon dioxide produced by yeast with different carbon sources for attraction of mosquitoes towards adult mosquito traps.

    Science.gov (United States)

    Sukumaran, D; Ponmariappan, S; Sharma, Atul K; Jha, Hemendra K; Wasu, Yogesh H; Sharma, Ajay K

    2016-04-01

    Surveillance is a prime requisite for controlling arthropod vectors like mosquitoes that transmit diseases such as malaria, dengue and chikungunya. Carbon dioxide (CO2) is one of the main cues from vertebrate breath that attracts mosquitoes towards the host. Hence, CO2 is used as an attractant during surveillance of mosquitoes either from commercial cylinders or dry ice for mosquito traps. In the present study, the biogenic carbon dioxide production was optimized with different carbon sources such as glucose, simple sugar and jaggery with and without yeast peptone dextrose (YPD) media using commercial baker's yeast. The results showed that yeast produced more biogenic CO2 with simple sugar as compared to other carbon sources. Further substrate concentration was optimized for the continuous production of biogenic CO2 for a minimum of 12 h by using 10 g of baker's yeast with 50 g of simple sugar added to 1.5 l distilled water (without YPD media) in a 2-l plastic bottle. This setup was applied in field condition along with two different mosquito traps namely Mosquito Killing System (MKS) and Biogents Sentinel (BGS) trap. Biogenic CO2 from this setup has increased the trapping efficiency of MKS by 6.48-fold for Culex quinquefasciatus, 2.62-fold for Aedes albopictus and 1.5-fold for Anopheles stephensi. In the case of BGS, the efficiency was found to be increased by 3.54-fold for Ae. albopictus, 4.33-fold for An. stephensi and 1.3-fold for Armigeres subalbatus mosquitoes. On the whole, plastic bottle setup releasing biogenic CO2 from sugar and yeast has increased the efficiency of MKS traps by 6.38-fold and 2.74-fold for BGS traps as compared to traps without biogenic CO2. The present study reveals that, among different carbon sources used, simple sugar as a substance (which is economical and readily available across the world) yielded maximum biogenic CO2 with yeast. This setup can be used as an alternative to CO2 cylinder and dry ice in any adult mosquito traps to

  17. Indoor application of attractive toxic sugar bait (ATSB in combination with mosquito nets for control of pyrethroid-resistant mosquitoes.

    Directory of Open Access Journals (Sweden)

    Zachary P Stewart

    Full Text Available BACKGROUND: Attractive toxic sugar bait (ATSB sprayed onto vegetation has been successful in controlling Anopheles mosquitoes outdoors. Indoor application of ATSB has yet to be explored. The purpose of this study was to determine whether ATSB stations positioned indoors have the potential to kill host-seeking mosquitoes and constitute a new approach to control of mosquito-borne diseases. METHODS: Insecticides were mixed with dyed sugar solution and tested as toxic baits against Anopheles arabiensis, An. Gambiae s.s. and Culex quinquefasciatus in feeding bioassay tests to identify suitable attractant-insecticide combinations. The most promising ATSB candidates were then trialed in experimental huts in Moshi, Tanzania. ATSB stations were hung in huts next to untreated mosquito nets occupied by human volunteers. The proportions of mosquitoes killed in huts with ATSB treatments relative to huts with non-insecticide control treatments huts were recorded, noting evidence of dye in mosquito abdomens. RESULTS: In feeding bioassays, chlorfenapyr 0.5% v/v, boric acid 2% w/v, and tolfenpyrad 1% v/v, mixed in a guava juice-based bait, each killed more than 90% of pyrethroid-susceptible An. Gambiae s.s. and pyrethroid-resistant An. arabiensis and Cx. quinquefasciatus. In the hut trial, mortality rates of the three ATSB treatments ranged from 41-48% against An. arabiensis and 36-43% against Cx. quinquefasciatus and all were significantly greater than the control mortalities: 18% for An. arabiensis, 7% for Cx. quinquefasciatus (p<0.05. Mortality rates with ATSB were comparable to those with long lasting insecticidal nets previously tested against the same species in this area. CONCLUSIONS: Indoor ATSB shows promise as a supplement to mosquito nets for controlling mosquitoes. Indoor ATSB constitute a novel application method for insecticide classes that act as stomach poisons and have not hitherto been exploited for mosquito control. Combined with LLIN, indoor

  18. Visualization and live imaging analysis of a mosquito saliva protein in host animal skin using a transgenic mosquito with a secreted luciferase reporter system.

    Science.gov (United States)

    Yamamoto, D S; Yokomine, T; Sumitani, M; Yagi, K; Matsuoka, H; Yoshida, S

    2013-12-01

    Mosquitoes inject saliva into a vertebrate host during blood feeding. The analysis of mosquito saliva in host skin is important for the elucidation of the inflammatory responses to mosquito bites, the development of antithrombotic drugs, and the transmission-blocking of vector-borne diseases. We produced transgenic Anopheles stephensi mosquitoes expressing the secretory luciferase protein (MetLuc) fused to a saliva protein (AAPP) in the salivary glands. The transgene product (AAPP-MetLuc) of transgenic mosquitoes exhibited both luciferase activity as a MetLuc and binding activity to collagen as an AAPP. The detection of luminescence in the skin of mice bitten by transgenic mosquitoes showed that AAPP-MetLuc was injected into the skin as a component of saliva via blood feeding. AAPP-MetLuc remained at the mosquito bite site in host skin with luciferase activity for at least 4 h after blood feeding. AAPP was also suspected of remaining at the site of injury caused by the mosquito bite and blocking platelet aggregation by binding to collagen. These results demonstrated the establishment of visualization and time-lapse analysis of mosquito saliva in living vertebrate host skin. This technique may facilitate the analysis of mosquito saliva after its injection into host skin, and the development of new drugs and disease control strategies.

  19. Biosynthesis of 130-kilodalton mosquito larvicide in the cyanobacterium Agmenellum quadruplicatum PR-6.

    OpenAIRE

    Angsuthanasombat, C; Panyim, S

    1989-01-01

    The 130-kilodalton mosquito larvicidal gene, cloned from Bacillus thuringiensis var. israelensis, was introduced into the cyanobacterium Agmenellum quadruplicatum PR-6 by plasmid transformation. Transformed cells synthesized 130-kilodalton delta-endotoxin protein and showed mosquito larvicidal activity. Results demonstrate a potential use of a cyanobacterium for biological control of mosquitoes.

  20. Biosynthesis of 130-kilodalton mosquito larvicide in the cyanobacterium Agmenellum quadruplicatum PR-6.

    Science.gov (United States)

    Angsuthanasombat, C; Panyim, S

    1989-09-01

    The 130-kilodalton mosquito larvicidal gene, cloned from Bacillus thuringiensis var. israelensis, was introduced into the cyanobacterium Agmenellum quadruplicatum PR-6 by plasmid transformation. Transformed cells synthesized 130-kilodalton delta-endotoxin protein and showed mosquito larvicidal activity. Results demonstrate a potential use of a cyanobacterium for biological control of mosquitoes.

  1. Detection of Brugia malayi microfilaria/Larvae in mosquito using Polimerase Chain Reaction.

    Directory of Open Access Journals (Sweden)

    Dyah Haryuningtyas

    2008-10-01

    Full Text Available Lymphathic filariasis that is also known as elepanthiasis is caused by infestation of 3 species nematode Wuchereria bancrofti, Brugia malayi and Brugia timori. In Indonesia 70% filariasis case caused by Brugia malayi. Mosquito species from genus Anopheles, Aedes, Culex, Mansonia and Armigeres are known as vector of this disease. Microfilaria detection on mosquito is one methode to know infection rate in vector population in endemic area.The objectives of the research were to study the ability of Hha1 repeat applicable to detect microfilaria/larvae in a pool of mosquitoes and to get description of adult mosquito night biting population lived in endemic area of filariasis brugian. Mosquito as positive control used in this research come from laboratory of parasitology of FKUI. Mosquito sample from the field was from Binawara and Kolam Kiri villages, South Kalimantan province. Mosquito were trapped then identified by its species. DNA of mosquitoes was extracted and then run by the PCR using Hha 1 repeat primer. Result of the research indicated that adult mosquitoes night biting from Binawara village consist of Culex, Mansonia, Anopheles genus and from Kolam Kiri village only from Mansonia genus. Hha 1 repeat primer is applicable to detect 1 mosquito infected with microfilaria/larvae in a pool of negative mosquitoes. Mosquito samplesfrom the two villages showing negative PCR.

  2. Mosquito Surveillance for Prevention and Control of Emerging Mosquito-Borne Diseases in Portugal — 2008–2014

    Science.gov (United States)

    Osório, Hugo C.; Zé-Zé, Líbia; Amaro, Fátima; Alves, Maria J.

    2014-01-01

    Mosquito surveillance in Europe is essential for early detection of invasive species with public health importance and prevention and control of emerging pathogens. In Portugal, a vector surveillance national program—REVIVE (REde de VIgilância de VEctores)—has been operating since 2008 under the custody of Portuguese Ministry of Health. The REVIVE is responsible for the nationwide surveillance of hematophagous arthropods. Surveillance for West Nile virus (WNV) and other flaviviruses in adult mosquitoes is continuously performed. Adult mosquitoes—collected mainly with Centre for Disease Control light traps baited with CO2—and larvae were systematically collected from a wide range of habitats in 20 subregions (NUTS III). Around 500,000 mosquitoes were trapped in more than 3,000 trap nights and 3,500 positive larvae surveys, in which 24 species were recorded. The viral activity detected in mosquito populations in these years has been limited to insect specific flaviviruses (ISFs) non-pathogenic to humans. Rather than emergency response, REVIVE allows timely detection of changes in abundance and species diversity providing valuable knowledge to health authorities, which may take control measures of vector populations reducing its impact on public health. This work aims to present the REVIVE operation and to expose data regarding mosquito species composition and detected ISFs. PMID:25396768

  3. Mosquito bite-caused eosinophilic dermatitis in cats.

    Science.gov (United States)

    Mason, K V; Evans, A G

    1991-06-15

    Eight cats had lesions on the nasal bridge, ears, and footpads, with histologic and hematologic features of a recently described seasonal form of eosinophilic granuloma complex. Four cats were examined in detail, and it was established that 2 of the 4 reacted to mosquito extract on intradermal skin testing read at 20 minutes. Neither of the 2 cats tested had deposits of immunoglobulins in lesional or perilesional skin. Lesions on all 4 cats resolved when kept at home behind insect screening, but flared up if the screening was removed. Mosquitoes that were observed to be biting and causing lesions were collected and identified. Other species of laboratory-reared mosquitoes were allowed to bite nonlesional skin of 1 affected cat, causing pruritus, erythematous crusting, and ulcerative lesions at the bite site, which was characterized histologically as eosinophilic dermatitis.

  4. 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

  5. Simple mathematical models for interacting wild and transgenic mosquito populations.

    Science.gov (United States)

    Li, Jia

    2004-05-01

    Two discrete-time models for interacting populations of wild and genetically altered mosquito are presented, where the genetically altered mosquitoes are grouped into a single population without distinguishing their zygosity. The birth and death rates for both populations are density-dependent, and the mating rates between the mosquitoes are assumed to be either constant or proportional to the total populations for the two models, respectively. The existence and stability of the boundary and positive equilibria are investigated. In particular, it is shown that bifurcations from both boundary and positive equilibria can appear for the model with proportional mating rates. Stable equilibria, periodic-doubling bifurcations, aperiodic oscillations, and chaotic behavior are all illustrated by numerical simulations.

  6. Evaluation of commercial products for personal protection against mosquitoes.

    Science.gov (United States)

    Revay, Edita E; Junnila, Amy; Xue, Rui-De; Kline, Daniel L; Bernier, Ulrich R; Kravchenko, Vasiliy D; Qualls, Whitney A; Ghattas, Nina; Müller, Günter C

    2013-02-01

    Human landing catch studies were conducted in a semi-field setting to determine the efficacy of seven commercial products used for personal protection against mosquitoes. Experiments were conducted in two empty, insecticide free, mesh-enclosed greenhouses, in Israel, with either 1500 Aedes albopictus or 1500 Culex pipiens released on consecutive study nights. The products tested in this study were the OFF!(®) Clip-On™ Mosquito Repellent (Metofluthrin 31.2%) and the Terminix(®) ALLCLEAR(®) Sidekick Mosquito Repeller (Cinnamon oil 10.5%; Eugenol 13%; Geranium oil 21%; Peppermint 5.3%; Lemongrass oil 2.6%), which are personal diffusers; Super Band™ Wristband (22% Citronella oil) and the PIC(®) Citronella Plus Wristband (Geraniol 15%; Lemongrass oil 5%, Citronella oil 1%); the Sonic Insect Repeller Keychain; the Mosquito Guard Patch (Oil of Lemon Eucalyptus 80mg), an adhesive-backed sticker for use on textiles; and the Mosquito Patch (vitamin B1 300mg), a transdermal patch. It was determined that the sticker, transdermal patch, wristbands and sonic device did not provide significant protection to volunteers compared with the mosquito attack rate on control volunteers who were not wearing a repellent device. The personal diffusers: - OFF!(®) Clip-On™ and Terminix(®) ALLCLEAR(®) Sidekick - provided superior protection compared with all other devices in this study. These diffusers reduced biting on the arms of volunteers by 96.28% and 95.26% respectively, for Ae. albopictus, and by 94.94% and 92.15% respectively, for Cx. pipiens. In a second trial conducted to compare these devices directly, biting was reduced by the OFF!(®) Clip-On™ and the Terminix(®) ALLCLEAR(®) by 87.55% and 92.83%, respectively, for Ae. albopictus, and by 97.22% and 94.14%, respectively, for Cx. pipiens. There was no significant difference between the performances of the two diffusers for each species.

  7. Survey of the mosquitoes (Diptera: Culicidae) of Mayotte.

    Science.gov (United States)

    Le Goff, Gilbert; Goodman, Steven M; Elguero, Eric; Robert, Vincent

    2014-01-01

    A transversal survey of immature mosquitoes was conducted on Mayotte Island (France) in the Comoros Archipelago, western Indian Ocean, with the aim to inventory the Culicidae and to document inter-species relationships in different habitats. In total 420 habitats were sampled for larvae and/or pupae mosquitoes, resulting in more than 6,000 specimens. Forty species belonging to 15 genera were collected, with eight taxa integrated for the first time to the Mayotte mosquito list. The most frequently recorded species were Stegomyia aegypti, St. albopicta, Anopheles gambiae and Eretmapodites subsimplicipes, the first three species being known vectors of viruses and parasites transmitted to humans. Mean species richness in habitats ranged from 1.00 to 3.29, with notable differences between habitats. For example, water-filled axils of banana leaves, tree-holes and crab-holes had low species richness, while cut bamboo, water pools, abandoned tires and marsh and swamp water had notably higher species richness. Twenty-seven mosquito species belonging to 12 genera were routinely collected (in ≥20% of at least one type of larval habitat) suggesting that multiple species play a role in the biocenosis of these aquatic habitats. Multispecies association was observed in 52% of the habitats. The co-occurrence of up to six species belonging to five genera was recorded in a single habitat. The mosquitoes of Mayotte show notable biogeographical affinities to those of Madagascar, as compared to the African continent. These two potential source areas are nearly equidistant from Mayotte, which in turn indicates biased dispersal from east to west. Our findings suggest that with relatively short-term intensive sampling in different habitats, it is possible to approach exhaustive species inventories based on collection of larvae. Mayotte, with its modest elevation range and land surface, has a notable species richness of mosquitoes with 45 well-documented species belonging to 15 genera.

  8. A Method for Dispensing Planaria (Dugesia dorotocephala) for Mosquito Control

    Science.gov (United States)

    1988-12-01

    other day. Planaria surviving Turbellaria ) was first shown by Lischetti (1919). after 14 days and those added to the population Studies have since...FILE COPY DECEMBER 198S OPERATIONAl. AND StCIENTIFI( NOTES A METHOD FOR DISPENSING PLANARIA (DI’E.S’IA DOROTOCEPHALA) FOR MOSQUITO CONTROL SW. N1...potential as number of experimental (12.64 ± 2.99) and con- a biological control agent of mosquitoes (Yu and trol (11.99 ± 2.47) planaria remaining after 14

  9. Aspirator Gun for High-Throughput Mosquito Bioassays

    Science.gov (United States)

    2012-01-01

    surveillance of Aedes aegypti in San Juan, Puerto Rico. J Am Mosq Control Assoc 10:119–124. Dietrick EJ. 1961. An improved backpack motor fan for suction...Bioassays Author(s): Robert L. Aldridge, W. Wayne Wynn, Seth C. Britch, and Kenneth J. Linthicum Source: Journal of the American Mosquito Control ...Association, 28(1):65-68. 2012. Published By: The American Mosquito Control Association DOI: http://dx.doi.org/10.2987/11-6195.1 URL: http://www.bioone.org

  10. Multitasking roles of mosquito labrum in oviposition and blood feeding

    Directory of Open Access Journals (Sweden)

    Young-Moo eChoo

    2015-10-01

    Full Text Available Reception of odorants by two main head appendages, antennae and maxillary palps, is essential for insects’ survival and reproduction. There is growing evidence in the literature suggesting that the proboscis is also an olfactory appendage and its function as an additional antenna has been previously proposed. We surmised that movements of the labrum towards blood vessel might be chemically oriented and, if so, there should be odorant receptors expressed in the labrum. To test this hypothesis, we first compared by quantitative PCR expression of odorant receptors (OR from the Southern house mosquito, Culex quinquefasciatus in antennae and proboscis and, subsequently compared OR expression in various proboscis parts. Our data suggested that a receptor for the oviposition attractant, skatole, CquiOR21, was not expressed in proboscis, whereas a receptor for another oviposition attractant, 4EP (4-ethylphenol, CquiOR99, and a receptor for the insect repellent DEET, CquiOR136, were expressed in the stylet of the proboscis, particularly in the tip of the labrum. In a dual-choice olfactometer, mosquitoes having the stylet coated with nail polish were attracted to 4EP in the same manner as the untreated mosquitoes. By contrast, in an oviposition assay, the stylet-treated mosquitoes did not discriminate 4EP from control oviposition cups, whereas the untreated mosquitoes (as well as mosquitoes having the labella coated laid significantly more egg rafts in cups treated with 4EP. Ablation experiments confirmed that 4EP was sensed by the labrum where CquiOR99 is highly expressed. Stylet-coated, labella-coated, and untreated mosquitoes laid significantly more egg rafts in skatole-treated cups than in control cups. Likewise, coating of proboscis structures with nail polish had no effect on DEET-mediated oviposition deterrence. In a behavioral arena designed to mimic a human arm, mosquitoes showed significantly reduced probing time when blood was impregnated

  11. Analysis of CHIKV in Mosquitoes Infected via Artificial Blood Meal.

    Science.gov (United States)

    Ledermann, Jeremy P; Powers, Ann M

    2016-01-01

    Having a mechanism to assess the transmission dynamics of a vector-borne virus is one critical component of understanding the life cycle of these viruses. Laboratory infection systems using artificial blood meals is one valuable approach for monitoring the progress of virus in its mosquito host and evaluating potential points for interruption of the cycle for control purposes. Here, we describe an artificial blood meal system with Chikungunya virus (CHIKV) and the processing of mosquito tissues and saliva to understand the movement and time course of virus infection in the invertebrate host.

  12. 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).

  13. Mosquito larvicidal activity of active constituent derived from Chamaecyparis obtusa leaves against 3 mosquito species.

    Science.gov (United States)

    Jang, Young-Su; Jeon, Ju-Hyun; Lee, Hoi-Seon

    2005-12-01

    Mosqutio larvicidal activity of Chamaecyparis obtusa leaf-derived materials against the 4th-stage larvae of Aedes aegypti (L.), Ochlerotatus togoi (Theobald), and Culex pipiens pallens (Coquillett) was examined in the laboratory. A crude methanol extract of C. obtusa leaves was found to be active (percent mortality rough) against the 3 species larvae; the hexane fraction of the methanol extract showed a strong larvicidal activity (100% mortality) at 100 ppm. The bioactive component in the C. obtusa leaf extract was characterized as beta-thujaplicin by spectroscopic analyses. The LC50 value of beta-thujaplicin was 2.91, 2.60, and 1.33 ppm against Ae. aegypti, Oc. togoi, and Cx. pipiens pallens larvae. This naturally occurring C. obtusa leaves-derived compound merits further study as a potential mosquito larval control agent or lead compound.

  14. Cultured skin microbiota attracts malaria mosquitoes

    Directory of Open Access Journals (Sweden)

    Takken Willem

    2009-12-01

    Full Text Available Abstract Background Host-seeking of the African malaria mosquito, Anopheles gambiae sensu stricto, is guided by human odours. The precise nature of the odours, and the composition of attractive blends of volatiles, remains largely unknown. Skin microbiota plays an important role in the production of human body odours. It is hypothesized that host attractiveness and selection of An. gambiae is affected by the species composition, density, and metabolic activity of the skin microbiota. A study is presented in which the production and constituency of volatile organic compounds (VOCs by human skin microbiota is examined and the behavioural responses of An. gambiae to VOCs from skin microbiota are investigated. Methods Blood agar plates incubated with skin microbiota from human feet or with a reference strain of Staphylococcus epidermidis were tested for their attractiveness to An. gambiae in olfactometer bioassays and indoor trapping experiments. Entrained air collected from blood agar plates incubated with natural skin microbiota or with S. epidermidis were analysed using GC-MS. A synthetic blend of the compounds identified was tested for its attractiveness to An. gambiae. Behavioural data were analysed by a χ2-test and GLM. GC-MS results were analysed by fitting an exponential regression line to test the effect of the concentration of bacteria. Results More An. gambiae were caught with blood agar plates incubated with skin bacteria than with sterile blood agar plates, with a significant effect of incubation time and dilution of the skin microbiota. When bacteria from the feet of four other volunteers were tested, similar effects were found. Fourteen putative attractants were found in the headspace of the skin bacteria. A synthetic blend of 10 of these was attractive to An. gambiae. Conclusions The discovery that volatiles produced by human skin microorganisms in vitro mediate An. gambiae host-seeking behaviour creates new opportunities for the

  15. Strategies for introducing Wolbachia to reduce transmission of mosquito-borne diseases.

    Directory of Open Access Journals (Sweden)

    Penelope A Hancock

    Full Text Available Certain strains of the endosymbiont Wolbachia have the potential to lower the vectorial capacity of mosquito populations and assist in controlling a number of mosquito-borne diseases. An important consideration when introducing Wolbachia-carrying mosquitoes into natural populations is the minimisation of any transient increase in disease risk or biting nuisance. This may be achieved by predominantly releasing male mosquitoes. To explore this, we use a sex-structured model of Wolbachia-mosquito interactions. We first show that Wolbachia spread can be initiated with very few infected females provided the infection frequency in males exceeds a threshold. We then consider realistic introduction scenarios involving the release of batches of infected mosquitoes, incorporating seasonal fluctuations in population size. For a range of assumptions about mosquito population dynamics we find that male-biased releases allow the infection to spread after the introduction of low numbers of females, many fewer than with equal sex-ratio releases. We extend the model to estimate the transmission rate of a mosquito-borne pathogen over the course of Wolbachia establishment. For a range of release strategies we demonstrate that male-biased release of Wolbachia-infected mosquitoes can cause substantial transmission reductions without transiently increasing disease risk. The results show the importance of including mosquito population dynamics in studying Wolbachia spread and that male-biased releases can be an effective and safe way of rapidly establishing the symbiont in mosquito populations.

  16. Aparelho de sucção tipo aspirador para captura de mosquitos A "vacuum-cleaner" type of suction apparatus for the collection of mosquitoes

    Directory of Open Access Journals (Sweden)

    Délsio Natal

    1984-10-01

    Full Text Available É feita a descrição de aparelho portátil de sucção tipo aspirador, para captura de mosquitos Culicidae. São sugeridas adaptações para coletas em diferentes situações. São feitos comentários sobre sua aplicação em pesquisa de mosquitos.A portable suction apparatus, which functions like a vacuum cleaner used for the collection of Culicidae mosquitoes is described. Adaptations for collecting in differents situations are suggested and some comments about its application in mosquitoes surveys are made.

  17. Allethrin-Based Mosquito Control Device Causing Knockdown, Morbidity, and Mortality in Four Species of Field-Caught Mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Bibbs, Christopher S; Fulcher, Ali; Xue, Rui-De

    2015-07-01

    A mosquito control device marketed for spatial repellency, the ThermaCELL Mosquito Repellent Appliance, was evaluated in semifield trials against multiple field-caught species of mosquito. Using paper and mesh cages, mosquito test groups of at least 30 mosquitoes were suspended in a 2,337 cubic foot outdoor space while two ThermaCELL repellent devices were active. After 30 min of treatment, cages were moved to the laboratory to observe knockdown, morbidity, and mortality for 24 h. Species tested included Aedes atlanticus Dyar and Knab (98% average mortality), Psorophora ferox Humboldt (97% average mortality), Psorophora columbiae Dyar and Knab (96% average mortality), and Aedes taeniorhynchus Wiedemann (84% average mortality). The repellent devices showed effectiveness with high knockdown and mortality across all species tested. Mosquito control devices like the ThermaCELL Mosquito Repellent Appliance may have further practical applications to help combat viral exposures by limiting host mosquitoes. Such devices may provide a functional alternative to DEET dependence in the current state of mosquito management.

  18. Predator-prey interactions and community structure: chironomids, mosquitoes and copepods in Heliconia imbricata (Musaceae).

    Science.gov (United States)

    Naeem, Shahid

    1988-11-01

    Evidence from both field observations and experimental work indicates that predation by larvae of a midge, Pentaneura n. sp. (Chironomidae), causes the low densities of mosquito larvae (Culicidae) found in the water filled bracts of Heliconia imbricata (Musaceae), microhabitats typically colonized by mosquitoes. This predation affects 2 species of mosquitoes, Wyeomyia pseudopecten, a resident species, and Trichoprosopon digitatum, a non-resident species. Predation keeps resident mosquito densities low while completely excluding the nonresident mosquito from the habitat. Both these effects of predation depend on the presence of an abundant alternative prey, an undescribed species of harpacticoid copepod found in the bracts. These copepod prey sustain chironomids when resident mosquito densities are low, permiting predator densities to remain high enough to exclude the non-resident mosquito. I discuss the evolutionary and ecological implications of predation structuring communities.

  19. The Role of Mosquitoes in the Diet of Adult Dragon and Damselflies (Odonata).

    Science.gov (United States)

    Pfitzner, Wolf Peter; Beck, Matthias; Weitzel, Thomas; Becker, Norbert

    2015-06-01

    The flood plains of the Upper Rhine Valley provide excellent conditions for the proliferation of mosquitoes as well as for the development of dragon and damselflies. It could be assumed that mosquitoes belong to the diet of the Odonata and that the latter could be harmed by the reduction of the mosquito population with the purpose of diminishing the massive nuisance for the people living there. A total of 41 adult dragonflies and damselflies were examined by immunoblot for remnants of mosquitoes in their guts. A rabbit antiserum against Aedes vexans proteins was used for the immunoblot. Only 3 Aeshna cyanea and 1 Platycnemis pennipes could be shown to have fed on mosquitoes. In specimens of the genus Sympetrum no mosquitoes were detected. It seems very doubtful that mosquitoes are an essential part of the Odonata diet.

  20. Mosquito (Diptera: Culicidae) Habitat Surveillance by Android Mobile Devices in Guangzhou, China.

    Science.gov (United States)

    Wu, Tai-Ping; Tian, Jun-Hua; Xue, Rui-De; Fang, Yi-Liang; Zheng, Ai-Hua

    2016-12-17

    In 2014, Guangzhou City, South China, suffered from its worst outbreak of dengue fever in decades. Larval mosquito habitat surveillance was carried out by using android mobile devices in four study sites in May 2015. The habitats with larval mosquitoes were recorded as photo waypoints in OruxMaps or in videos. The total number of potential mosquito habitats was 342, of which 166 (49%) were found to have mosquito larvae or pupae. Small containers were the most abundant potential habitats, accounting for 26% of the total number. More mosquito larvae and pupae, were found in small containers than in other objects holding water, for example, potted or hydroponic plants (p mobile devices are a convenient and useful tool for surveillance of mosquito habitats, and the enhancement of source reduction may benefit the prevention and control of dengue vector mosquitoes.

  1. Willingness to Pay for Mosquito Control in Key West, Florida and Tucson, Arizona.

    Science.gov (United States)

    Dickinson, Katherine L; Hayden, Mary H; Haenchen, Steven; Monaghan, Andrew J; Walker, Kathleen R; Ernst, Kacey C

    2016-04-01

    Mosquito-borne illnesses like West Nile virus (WNV) and dengue are growing threats to the United States. Proactive mosquito control is one strategy to reduce the risk of disease transmission. In 2012, we measured the public's willingness to pay (WTP) for increased mosquito control in two cities: Key West, FL, where there have been recent dengue outbreaks, and Tucson, AZ, where dengue vectors are established and WNV has been circulating for over a decade. Nearly three quarters of respondents in both cities (74% in Tucson and 73% in Key West) would be willing to pay $25 or more annually toward an increase in publicly funded mosquito control efforts. WTP was positively associated with income (both cities), education (Key West), and perceived mosquito abundance (Tucson). Concerns about environmental impacts of mosquito control were associated with lower WTP in Key West. Expanded mosquito control efforts should incorporate public opinion as they respond to evolving disease risks.

  2. How Mosquitoes Walk on Water and Up Walls

    Institute of Scientific and Technical Information of China (English)

    Andrea; Thompson; 施小英

    2007-01-01

    Mosquitoes may be annoying,disease-carrying, blood-sucking pests,but they have a pair of talents that no other animal has:They can both walk up walls and walk on water,and a new study reveals exactly how they manage these circus feats.

  3. Detecting multiple DNA human profile from a mosquito blood meal.

    Science.gov (United States)

    Rabêlo, K C N; Albuquerque, C M R; Tavares, V B; Santos, S M; Souza, C A; Oliveira, T C; Moura, R R; Brandão, L A C; Crovella, S

    2016-08-26

    Criminal traces commonly found at crime scenes may present mixtures from two or more individuals. The scene of the crime is important for the collection of various types of traces in order to find the perpetrator of the crime. Thus, we propose that hematophagous mosquitoes found at crime scenes can be used to perform genetic testing of human blood and aid in suspect investigation. The aim of the study was to obtain a single Aedes aegypti mosquito profile from a human DNA mixture containing genetic materials of four individuals. We also determined the effect of blood acquisition time by setting time intervals of 24, 48, and 72 h after the blood meal. STR loci and amelogenin were analyzed, and the results showed that human DNA profiles could be obtained from hematophagous mosquitos at 24 h following the blood meal. It is possible that hematophagous mosquitoes can be used as biological remains at the scene of the crime, and can be used to detect human DNA profiles of up to four individuals.

  4. Sodium channel gene expression in mosquitoes, Aedes albopictus (S.)

    Institute of Scientific and Technical Information of China (English)

    NANNAN LIU; QIANG XU; LEE ZHANG

    2006-01-01

    A mosquito strain of Aerdes albopictus,HAmAalG0,from Huntsville,Alabama,USA,showed a normal susceptibility and low tolerance to permethrin and resmethrin (pyrethroid insecticides) compared to a susceptible Ikaken strain,even though these pyrethroid insecticides have been used in the field for a long period of time in Alabama.Recently,we treated HAmAalG0 in the laboratory with permethrin for five generations and detected no significant change in the level of resistance to permethrin in the selected mosquitoes,HAmAalG5,compared with the parental strain HAmAalG0. We then examined the allelic expression at the L-to-F kdr site of the sodium channel gene in the Aedes mosquitoes to address our hypothesis that the L-to-F kdr mutation was not present in HAmAalG0 and HAmAalG5 mosquitoes. We found that every tested individual in Ikaken,HAmAalG0,and HAmAalG5 populations expressed a codon of CTA at the L-to-F kdr site encoding Leu,strongly corresponding to their susceptibility to insecticides.

  5. Formulas of components of citronella oil against mosquitoes (Aedes aegypti).

    Science.gov (United States)

    Hsu, Wey-Shin; Yen, Jui-Hung; Wang, Yei-Shung

    2013-01-01

    The mosquito Aedes aegypti is an epidemic vector of several diseases such as dengue fever and yellow fever. Several pesticides are used to control the mosquito population. Because of their frequent use, some mosquitoes have developed resistance. In this study, we used the Y-tube olfactometer to test essential oils of Cymbopogon species and screened specific formulas of components as repellents against Ae. aegypti. At 400 μL, the extracted oil of citronella grass (Cymbopogon nardus) and myrcene produced a low-active response by inhibiting mosquito host-seeking activity. Citronella grass, lemon grass (Cymbopogon citratus), citral and myrcene also produced a low-treatment response to repellents, for more potential to affect host-seeking behavior. Furthermore, the mixture of citral, myrcene, and citronellal oil (C:M:Ci = 6:4:1) greatly affected and inhibited host-seeking behavior (76% active response; 26% treatment response with 40 μL; 42.5%, 18% with 400 μL; and 19%, 23% with 1000 μL). As compared with the result for N,N-diethyl-3-methylbenzamide (DEET; 44%, 22% with 400 μL), adjusting the composition formulas of citronella oil had a synergistic effect, for more effective repellent against Ae. aegypti.

  6. Risk Factors for Mosquito House Entry in the Lao PDR

    NARCIS (Netherlands)

    Hiscox, A.F.; Khammanithong, P.; Kaul, S.; Sananikhom, P.; Luthi, R.; Hill, N.; Brey, P.T.; Lindsay, S.W.

    2013-01-01

    Background Construction of the Nam Theun 2 hydroelectric project and flooding of a 450 km2 area of mountain plateau in south-central Lao PDR resulted in the resettlement of 6,300 people to newly built homes. We examined whether new houses would have altered risk of house entry by mosquitoes compared

  7. Malaria-induced changes in host odors enhance mosquito attraction.

    Science.gov (United States)

    De Moraes, Consuelo M; Stanczyk, Nina M; Betz, Heike S; Pulido, Hannier; Sim, Derek G; Read, Andrew F; Mescher, Mark C

    2014-07-29

    Vector-borne pathogens may alter traits of their primary hosts in ways that influence the frequency and nature of interactions between hosts and vectors. Previous work has reported enhanced mosquito attraction to host organisms infected with malaria parasites but did not address the mechanisms underlying such effects. Here we document malaria-induced changes in the odor profiles of infected mice (relative to healthy individuals) over the course of infection, as well as effects on the attractiveness of infected hosts to mosquito vectors. We observed enhanced mosquito attraction to infected mice during a key period after the subsidence of acute malaria symptoms, but during which mice remained highly infectious. This attraction corresponded to an overall elevation in the volatile emissions of infected mice observed during this period. Furthermore, data analyses--using discriminant analysis of principal components and random forest approaches--revealed clear differences in the composition of the volatile blends of infected and healthy individuals. Experimental manipulation of individual compounds that exhibited altered emission levels during the period when differential vector attraction was observed also elicited enhanced mosquito attraction, indicating that compounds being influenced by malaria infection status also mediate vector host-seeking behavior. These findings provide important insights into the cues that mediate vector attraction to hosts infected with transmissible stages of malaria parasites, as well as documenting characteristic changes in the odors of infected individuals that may have potential value as diagnostic biomarkers of infection.

  8. Innate Cellular Immune Responses in Aedes caspius (Diptera: Culicidae) Mosquitoes.

    Science.gov (United States)

    Soliman, D E; Farid, H A; Hammad, R E; Gad, A M; Bartholomay, L C

    2016-03-01

    Mosquitoes transmit a variety of pathogens that have devastating consequences for global public and veterinary health. Despite their capacity to serve as vectors, these insects have a robust capacity to respond to invading organisms with strong cellular and humoral immune responses. In Egypt, Aedes caspius (Pallas, 1771) has been suspected to act as a bridge vector of Rift Valley Fever virus between animals and humans. Microscopic analysis of Ae. caspius hemolymph revealed the presence of phagocytic cells called granulocytes. We further evaluated cellular immune responses produced by Ae. caspius as a result of exposure to a Gram-negative, and Gram-positive bacterium, and to latex beads. After challenge, a rapid and strong phagocytic response against either a natural or synthetic invader was evident. Hemocyte integrity in bacteria-inoculated mosquitoes was not morphologically affected. The number of circulating granulocytes decreased with age, reducing the overall phagocytic capacity of mosquitoes over time. The magnitude and speed of the phagocytic response suggested that granulocytes act as an important force in the battle against foreign invaders, as has been characterized in other important mosquito vector species.

  9. Advances in methods for colour marking of mosquitoes

    NARCIS (Netherlands)

    Verhulst, N.O.; Loonen, J.A.C.M.; Takken, W.

    2013-01-01

    Background: Different techniques are available for colour marking insects and each technique may be suitable for different insect species. Mosquitoes can be marked to determine population size, distribution and flight distance or distinguish closely related species. In this study, two methods of col

  10. Nectar feeding by the early-spring mosquito Aedes provocans.

    Science.gov (United States)

    Smith, S M; Gadawski, R M

    1994-07-01

    Nectar feeding by males and females of the mosquito Aedes provocans was studied at a site near Belleville, Ontario, Canada. Canada plum, Prunus nigra, and especially pin cherry, P. pensylvanica, bloomed contemporaneously with the emergence of Ae. provocans and were important nectar sources for adult mosquitoes during their first week of life. Blossoms of P. pensylvanica shielded for 24 h from foragers produced an average of 0.14 mg of sugar (approximately 2.3J). This nectar was avidly sought by both sexes of Ae. provocans; > 97% of the blossoms were visited by mosquitoes in the first few days of blooming. Young adult mosquitoes were found on blossoms at all hours of the day and night; feeding on P. nigra was strongly eocrepuscular, whereas on P. pensylvanica feeding was much less strongly periodic. Adults foraged for nectar in an energy-conserving, pedestrian strategy, devoting 56% (females) and 68% (males) of their time on blossoms to nectar feeding during foraging bouts that lasted a median of 5.3 min. Both sexes sought nectar soon after emergence--males before they had completed hypopygial rotation or swarmed, and females before mating or host seeking. Female Ae. provocans sought nectar in all stages of oogenesis, but primarily at the initiation of a gonotrophic cycle. Energy stores in the crop averaged 18J per female, with a distribution that depended on gonotrophic age and parity.

  11. Conidiobolus macrosporus (Entomophthorales), a mosquito pathogen in Central Brazil

    Science.gov (United States)

    A new fungal pathogen of Culicinae (Diptera: Culicidae) adults, Conidiobolus macrosporus (Ancylistaceae), was detected and isolated during a survey of mosquito pathogens close to the city of Aruanã, Goiás State of Brazil, in December 2014. The morphological characteristics of C. macrosporus are pres...

  12. The use of sterilized mosquito nets for hernioplasty

    DEFF Research Database (Denmark)

    Sørensen, C G; Rosenberg, J

    2012-01-01

    Hernia repair is among the most frequent surgeries performed. Surgeons prefer the tension-free mesh repair, but in large parts of the world, commercial meshes are unavailable or unaffordable. Consequently, surgeons have been experimenting with insertion of inexpensive non-commercial meshes, the m......, the most common being a non-impregnated, sterilized mosquito net....

  13. Genome of a mosquito-killing bacterium decoded

    Institute of Scientific and Technical Information of China (English)

    2008-01-01

    @@ Researchers with the CAS Wuhan Institute of Virology (WHIOV) recently completed the genome sequencing of a mosquitocidal bacterium Bacillus shaericus C3-41. The feat, first of its kind in China, is expected to further promote the bio-control studies of mosquitoes.

  14. Neato Mosquito: An Elementary Curriculum Guide. 2nd Edition.

    Science.gov (United States)

    Nasci, Roger S.; Herrington, James E.

    This curriculum guide was designed with the purpose of developing public awareness of LaCrosse (LAC) encephalitis, which is a mosquito transmitted disease. LAC cases have been increasing in large numbers in the Upper Midwest and Great Lakes regions during recent years. This disease primarily affects children under the age of 15, and this guide…

  15. The effect of gene drive on containment of transgenic mosquitoes.

    Science.gov (United States)

    Marshall, John M

    2009-05-21

    Mosquito-borne diseases such as malaria and dengue fever continue to be a major health problem through much of the world. Several new potential approaches to disease control utilize gene drive to spread anti-pathogen genes into the mosquito population. Prior to a release, these projects will require trials in outdoor cages from which transgenic mosquitoes may escape, albeit in small numbers. Most genes introduced in small numbers are very likely to be lost from the environment; however, gene drive mechanisms enhance the invasiveness of introduced genes. Consequently, introduced transgenes may be more likely to persist than ordinary genes following an accidental release. Here, we develop stochastic models to analyze the loss probabilities for several gene drive mechanisms, including homing endonuclease genes, transposable elements, Medea elements, the intracellular bacterium Wolbachia, engineered underdominance genes, and meiotic drive. We find that Medea and Wolbachia present the best compromise between invasiveness and containment for the six gene drive systems currently being considered for the control of mosquito-borne disease.

  16. USDA Mosquito Control Product Research for the US Military

    Science.gov (United States)

    New techniques that were developed at the USDA to protect deployed military troops from the threat of vector-borne diseases and are also applicable for use by civilian mosquito control program use are described. Techniques to be illustrated include: (1) novel military personal protection methods, (2...

  17. Multiple activities of insect repellents on odorant receptors in mosquitoes

    Science.gov (United States)

    Several lines of evidence suggest that insect repellent molecules reduce mosquito-host contacts by interacting with odorants and odorant receptors (ORs) ultimately affecting olfactory-driven behaviors. We describe the molecular effects of ten insect repellents and a pyrethroid insecticide with known...

  18. Wolbachia surface protein induces innate immune responses in mosquito cells

    Directory of Open Access Journals (Sweden)

    Pinto Sofia B

    2012-01-01

    Full Text Available Abstract Background Wolbachia endosymbiotic bacteria are capable of inducing chronic upregulation of insect immune genes in some situations and this phenotype may influence the transmission of important insect-borne pathogens. However the molecules involved in these interactions have not been characterized. Results Here we show that recombinant Wolbachia Surface Protein (WSP stimulates increased transcription of immune genes in mosquito cells derived from the mosquito Anopheles gambiae, which is naturally uninfected with Wolbachia; at least two of the upregulated genes, TEP1 and APL1, are known to be important in Plasmodium killing in this species. When cells from Aedes albopictus, which is naturally Wolbachia-infected, were challenged with WSP lower levels of upregulation were observed than for the An. gambiae cells. Conclusions We have found that WSP is a strong immune elicitor in a naturally Wolbachia-uninfected mosquito species (Anopheles gambiae while a milder elicitor in a naturally-infected species (Aedes albopictus. Since the WSP of a mosquito non-native (nematode Wolbachia strain was used, these data suggest that there is a generalized tolerance to WSP in Ae. albopictus.

  19. A Multi-detection Assay for Malaria Transmitting Mosquitoes

    Science.gov (United States)

    Lee, Yoosook; Weakley, Allison M.; Nieman, Catelyn C.; Malvick, Julia; Lanzaro, Gregory C.

    2015-01-01

    The Anopheles gambiae species complex includes the major malaria transmitting mosquitoes in Africa. Because these species are of such medical importance, several traits are typically characterized using molecular assays to aid in epidemiological studies. These traits include species identification, insecticide resistance, parasite infection status, and host preference. Since populations of the Anopheles gambiae complex are morphologically indistinguishable, a polymerase chain reaction (PCR) is traditionally used to identify species. Once the species is known, several downstream assays are routinely performed to elucidate further characteristics. For instance, mutations known as KDR in a para gene confer resistance against DDT and pyrethroid insecticides. Additionally, enzyme-linked immunosorbent assays (ELISAs) or Plasmodium parasite DNA detection PCR assays are used to detect parasites present in mosquito tissues. Lastly, a combination of PCR and restriction enzyme digests can be used to elucidate host preference (e.g., human vs. animal blood) by screening the mosquito bloodmeal for host-specific DNA. We have developed a multi-detection assay (MDA) that combines all of the aforementioned assays into a single multiplex reaction genotyping 33SNPs for 96 or 384 samples at a time. Because the MDA includes multiple markers for species, Plasmodium detection, and host blood identification, the likelihood of generating false positives or negatives is greatly reduced from previous assays that include only one marker per trait. This robust and simple assay can detect these key mosquito traits cost-effectively and in a fraction of the time of existing assays. PMID:25867057

  20. Alphavirus transducing system: tools for visualizing infection in mosquito vectors.

    Science.gov (United States)

    Phillips, Aaron; Mossel, Eric; Sanchez-Vargas, Irma; Foy, Brian; Olson, Ken

    2010-11-24

    Alphavirus transducing systems (ATSs) are important tools for expressing genes of interest (GOI) during infection. ATSs are derived from cDNA clones of mosquito-borne RNA viruses (genus Alphavirus; family Togaviridae). The Alphavirus genus contains about 30 different mosquito-borne virus species. Alphaviruses are enveloped viruses and contain single-stranded RNA genomes (~11.7 Kb). Alphaviruses transcribe a subgenomic mRNA that encodes the structural proteins of the virus required for encapsidation of the genome and maturation of the virus. Alphaviruses are usually highly lytic in vertebrate cells, but persistently infect susceptible mosquito cells with minimal cytopathology. These attributes make them excellent tools for gene expression in mosquito vectors. The most common ATSs in use are derived from Sindbis virus (SINV). The broad species tropism of SINV allows for infection of insect, avian, and mammalian cells8. However, ATSs have been derived from other alphaviruses as well. Foreign gene expression is made possible by the insertion of an additional viral subgenomic RNA initiation site or promoter. ATSs in which an exogenous gene sequence is positioned 5' to the viral structural genes is used for stable protein expression in insects. ATSs, in which a gene sequence is positioned 3' to the structural genes, is used to trigger RNAi and silence expression of that gene in the insect. ATSs have proven to be valuable tools for understanding vector-pathogen interactions, molecular details of viral replication and maintenance infectious cycles. In particular, the expression of fluorescent and bioluminescent reporters has been instrumental tracking the viral infection in the vector and virus transmission. Additionally, the vector immune response has been described using two strains of SINV engineered to express GFP(2,9). Here, we present a method for the production of SINV containing a fluorescent reporter (GFP) from the cDNA infectious clone. Infectious, full

  1. Consumo de pre-adultos de mosquitos por peces ornamentales

    Directory of Open Access Journals (Sweden)

    Marco Polo Franco Archundia

    2015-01-01

    Full Text Available La investigación sobre alternativas de alimento para especies acuáticas con alto potencial económico, es uno de los principales temas de estudio en la acuicultura. En la presente investigación se evaluó el consumo de pre-adultos de mosquito por cuatro especies ícticas ornamentales: Carassius auratus, Pterophyllum scalare, Danio rerio y Xiphophorus helleri. El diseño experimental consistió en cuatro tratamientos, con tres réplicas. Cada ensayo se realizó de manera independiente entre especies. En cada acuario (1 l se colocaron dos peces juveniles, con peso húmedo y longitud total (promedio ± desviación estándar conocidos. Se suministraron en un tratamiento 100 larvas y en otro 100 pupas de mosquito. La tasa diaria de consumo de larvas y pupas se registró a un intervalo de tres horas durante un ciclo de 24 horas por especie. El peso húmedo de pre-adultos de mosquito difirió 5.20% y el seco 37.69%; en ambos casos, superior en las pupas (p < 0.001. Los peces fueron más activos durante la fase luminosa, 09:00-18:00 h, evidenciado por una mayor tasa de consumo de larvas y pupas de mosquito. Carassius auratus presentó el mayor consumo de larvas/pez/24 horas 131.33 ± 4.16 y de pupas/pez/24 horas 86.16 ± 3.20. Lo anterior difirió significativamente con respecto a P. scalare, D. rerio y X. helleri (p < 0.001. Finalmente, Carassius auratus presentó la mayor capacidad de consumo de pre-adultos de mosquitos.

  2. Energetic cost of insecticide resistance in Culex pipiens mosquitoes.

    Science.gov (United States)

    Rivero, A; Magaud, A; Nicot, A; Vézilier, J

    2011-05-01

    The extensive use of insecticides to control vector populations has lead to the widespread development of different mechanisms of insecticide resistance. Mutations that confer insecticide resistance are often associated to fitness costs that prevent them from spreading to fixation. In vectors, such fitness costs include reductions in preimaginal survival, adult size, longevity, and fecundity. The most commonly invoked explanation for the nature of such pleiotropic effects of insecticide resistance is the existence of resource-based trade-offs. According to this hypothesis, insecticide resistance would deplete the energetic stores of vectors, reducing the energy available for other biological functions and generating trade-offs between insecticide resistance and key life history traits. Here we test this hypothesis by quantifying the energetic resources (lipids, glycogen, and glucose) of larvae and adult females of the mosquito Culex pipiens L. resistant to insecticides through two different mechanisms: esterase overproduction and acetylcholinesterase modification. We find that, as expected from trade-off theory, insecticide resistant mosquitoes through the overproduction of esterases contain on average 30% less energetic reserves than their susceptible counterparts. Acetylcholinesterase-modified mosquitoes, however, also showed a significant reduction in energetic resources (20% less). We suggest that, in acetylcholinesterase-modified mosquitoes, resource depletion may not be the result of resource-based trade-offs but a consequence of the hyperactivation of the nervous system. We argue that these results not only provide a mechanistic explanation for the negative pleiotropic effects of insecticide resistance on mosquito life history traits but also can have a direct effect on the development of parasites that depend on the vector's energetic reserves to fulfil their own metabolic needs.

  3. Mosquito fauna and perspectives for integrated control of urban vector-mosquito populations in Southern Benin (West Africa).

    Science.gov (United States)

    Lingenfelser, Andre; Rydzanicz, Katarzyna; Kaiser, Achim; Becker, Norbert

    2010-01-01

    This study aims at an integrated vector management (IVM) concept of implementing biological control agents against vector mosquito larvae as a cost-effective and scalable control strategy. In the first step, the mosquito species composition fauna of southern Benin was studied using standard entomological procedures in natural and man-made habitats. Altogether, 24 species belonging to 6 genera of mosquitoes Aedes, Anopheles, Culex, Mansonia, Uranotaenia, Ficalbia were recorded. Five species, Cx. thalassius, Cx. nebulosus, Cx. perfuscus, Cx. pocilipes and Fi. mediolineata are described the first time for Benin. The local mosquito species showed high susceptibility to a Bacillus sphaericus formulation (VectoLex(R) WDG ) in a standardized field test. A dosage of 1 g/m(2) was effective to achieve 100 percent mortality rate for Cx. quinquefasciatus late instar larvae in a sewage habitat, with a residual effect of up to 7 days. After more than 1 year of baseline data collection, operational larviciding with B. thuringiensis var. israelensis and B. sphaericus was commenced in 2006 in selected areas. Microbial insecticides products for larval control show great potential within IVM programmes and may augment control efforts against adult insects, such as the use of insecticide-treated bed nets or indoor wall spraying in many parts of Africa.

  4. Towards mosquito sterile insect technique programmes: exploring genetic, molecular, mechanical and behavioural methods of sex separation in mosquitoes.

    Science.gov (United States)

    Gilles, Jeremie R L; Schetelig, Marc F; Scolari, Francesca; Marec, František; Capurro, Margareth L; Franz, Gerald; Bourtzis, Kostas

    2014-04-01

    When considering a mosquito release programme, one of the first issues to be addressed is how to eliminate/separate the females. The greatest number of options might eventually be available for those who can use transgenic mosquitoes, but the inherent characteristics of the target species may also provide possibilities for interim measures until more efficient methods can be developed. Differences in intrinsic size, in behaviour and in development rate between females and males are often available and useful for sexing. Efficient species-specific systems for eliminating females at the embryo stage have been developed, but most have since been discarded due to lack of use. Ideal systems specifically kill female embryos using some treatment that can be manipulated during production. Such killing systems are far more efficient than using intrinsic sexual differences, but they systems require selectable genetic markers and sex-linkage created by rare random chromosomal rearrangements. While intrinsic sexual differences should not be considered as long-term candidates for the development of robust and efficient sexing approaches, in the absence of these, the accessibility and integration of less efficient systems can provide a stop-gap measure that allows rapid start up with a minimum of investment. The International Atomic Energy Agency is funding over a 5 year period (2013-2018) a new Coordinated Research Project on "Exploring Genetic, Molecular, Mechanical and Behavioural Methods of Sex Separation in Mosquitoes" to network researchers and to address the critical need of genetic sexing strains for the implementation of the sterile insect technique (using radiation-sterilised or transgenic male mosquitoes) and for insect incompatibility technique programmes against disease-transmitting mosquitoes.

  5. Driven to extinction? The ethics of eradicating mosquitoes with gene-drive technologies.

    Science.gov (United States)

    Pugh, Jonathan

    2016-09-01

    Mosquito-borne diseases represent a significant global disease burden, and recent outbreaks of such diseases have led to calls to reduce mosquito populations. Furthermore, advances in 'gene-drive' technology have raised the prospect of eradicating certain species of mosquito via genetic modification. This technology has attracted a great deal of media attention, and the idea of using gene-drive technology to eradicate mosquitoes has been met with criticism in the public domain. In this paper, I shall dispel two moral objections that have been raised in the public domain against the use of gene-drive technologies to eradicate mosquitoes. The first objection invokes the concept of the 'sanctity of life' in order to claim that we should not drive an animal to extinction. In response, I follow Peter Singer in raising doubts about general appeals to the sanctity of life, and argue that neither individual mosquitoes nor mosquitoes species considered holistically are appropriately described as bearing a significant degree of moral status. The second objection claims that seeking to eradicate mosquitoes amounts to displaying unacceptable degrees of hubris. Although I argue that this objection also fails, I conclude by claiming that it raises the important point that we need to acquire more empirical data about, inter alia, the likely effects of mosquito eradication on the ecosystem, and the likelihood of gene-drive technology successfully eradicating the intended mosquito species, in order to adequately inform our moral analysis of gene-drive technologies in this context.

  6. Fighting Arbovirus Transmission: Natural and Engineered Control of Vector Competence in Aedes Mosquitoes.

    Science.gov (United States)

    Kean, Joy; Rainey, Stephanie M; McFarlane, Melanie; Donald, Claire L; Schnettler, Esther; Kohl, Alain; Pondeville, Emilie

    2015-03-23

    Control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. In this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. The study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are required to control arbovirus replication in mosquitoes, though more factors influencing vector competence are likely to be discovered. We will discuss key aspects of these pathways as targets either for selection of naturally resistant mosquito populations or for mosquito genetic manipulation. Moreover, we will consider the use of endosymbiotic bacteria such as Wolbachia, which in some cases have proven to be remarkably efficient in disrupting arbovirus transmission by mosquitoes, but also the use of naturally occurring insect-specific viruses that may interfere with arboviruses in mosquito vectors. Finally, we will discuss the use of paratransgenesis as well as entomopathogenic fungi, which are also proposed strategies to control vector competence.

  7. Worthy of their name: how floods drive outbreaks of two major floodwater mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Berec, Ludĕk; Gelbic, Ivan; Sebesta, Oldrich

    2014-01-01

    An understanding of how climate variables drive seasonal dynamics of mosquito populations is critical to mitigating negative impacts of potential outbreaks, including both nuisance effects and risk of mosquito-borne infectious disease. Here, we identify climate variables most affecting seasonal dynamics of two major floodwater mosquitoes, Aedes vexans (Meigen, 1830) and Aedes sticticus (Meigen, 1838) (Diptera: Culicidae), along the lower courses of the Dyje River, at the border between the Czech Republic and Austria. Monthly trap counts of both floodwater mosquitoes varied both across sites and years. Despite this variability, both models used to fit the observed data at all sites (and especially that for Ae. sticticus) and site-specific models fitted the observed data quite well. The most important climate variables we identified-temperature and especially flooding-were driving seasonal dynamics of both Aedes species. We suggest that flooding determines seasonal peaks in the monthly mosquito trap counts while temperature modulates seasonality in these counts. Hence, floodwater mosquitoes indeed appear worthy of their name. Moreover, the climate variables we considered for modeling were able reasonably to predict mosquito trap counts in the month ahead. Our study can help in planning flood management; timely notification of people, given that these mosquitoes are a real nuisance in this region; public health policy management to mitigate risk from such mosquito-borne diseases as that caused in humans by the Tahyna virus; and anticipating negative consequences of climate change, which are expected only to worsen unless floods, or the mosquitoes themselves, are satisfactorily managed.

  8. Clinical categories of exaggerated skin reactions to mosquito bites and their pathophysiology.

    Science.gov (United States)

    Tatsuno, Kazuki; Fujiyama, Toshiharu; Matsuoka, Hiroyuki; Shimauchi, Takatoshi; Ito, Taisuke; Tokura, Yoshiki

    2016-06-01

    Mosquito bites are skin irritating reactions, which usually resolve spontaneously without intensive medical care. However, in certain situations, mosquito bites may form a more vicious reaction, sometimes accompanying fever and systemic symptoms. In such cases, the presence of rare hematological disorders, abnormalities in eosinophils and/or association with Epstein-Barr virus (EBV) may underlie. Importantly, hypersensitivity to mosquito bites (HMB), which is characterized by necrotic skin reactions to mosquito bites with various systemic symptoms, is often observed in association with EBV infection and natural killer (NK) cell lymphoproliferative disorder. Exaggerated skin reaction to mosquito bites is also seen in Wells' syndrome. While strong Th2-skewing immune dysregulation is apparent in the patients, they also show robust CD4(+) T cell proliferation in response to mosquito salivary gland extracts, indicating close association between Wells' syndrome and mosquito bites. Similar skin reaction to mosquito bites is also noticed in certain types of B cell neoplasm, although the role of B cells in this peculiar reaction to mosquito bites is yet to be elucidated. In this review, we will discuss the current knowledge of exaggerated reaction toward mosquito bites seen in conjunction with these unique hematological disorders, and examine the scientific studies and observations reported in previous literatures to organize our current understanding of the pathogenesis of this distinct disorder.

  9. Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.

    Directory of Open Access Journals (Sweden)

    Leon E Hugo

    2014-02-01

    Full Text Available The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April and dry/hot (May-August seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d, respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

  10. Adult survivorship of the dengue mosquito Aedes aegypti varies seasonally in central Vietnam.

    Science.gov (United States)

    Hugo, Leon E; Jeffery, Jason A L; Trewin, Brendan J; Wockner, Leesa F; Nguyen, Thi Yen; Nguyen, Hoang Le; Nghia, Le Trung; Hine, Emma; Ryan, Peter A; Kay, Brian H

    2014-02-01

    The survival characteristics of the mosquito Aedes aegypti affect transmission rates of dengue because transmission requires infected mosquitoes to survive long enough for the virus to infect the salivary glands. Mosquito survival is assumed to be high in tropical, dengue endemic, countries like Vietnam. However, the survival rates of wild populations of mosquitoes are seldom measured due the difficulty of predicting mosquito age. Hon Mieu Island in central Vietnam is the site of a pilot release of Ae. aegypti infected with a strain of Wolbachia pipientis bacteria (wMelPop) that induces virus interference and mosquito life-shortening. We used the most accurate mosquito age grading approach, transcriptional profiling, to establish the survival patterns of the mosquito population from the population age structure. Furthermore, estimations were validated on mosquitoes released into a large semi-field environment consisting of an enclosed house, garden and yard to incorporate natural environmental variability. Mosquito survival was highest during the dry/cool (January-April) and dry/hot (May-August) seasons, when 92 and 64% of Hon Mieu mosquitoes had survived to an age that they were able to transmit dengue (12 d), respectively. This was reduced to 29% during the wet/cool season from September to December. The presence of Ae. aegypti older than 12 d during each season is likely to facilitate the observed continuity of dengue transmission in the region. We provide season specific Ae. aegypti survival models for improved dengue epidemiology and evaluation of mosquito control strategies that aim to reduce mosquito survival to break the dengue transmission cycle.

  11. Transcriptome analysis of Aedes aegypti transgenic mosquitoes with altered immunity.

    Directory of Open Access Journals (Sweden)

    Zhen Zou

    2011-11-01

    Full Text Available The mosquito immune system is involved in pathogen-elicited defense responses. The NF-κB factors REL1 and REL2 are downstream transcription activators of Toll and IMD immune pathways, respectively. We have used genome-wide microarray analyses to characterize fat-body-specific gene transcript repertoires activated by either REL1 or REL2 in two transgenic strains of the mosquito Aedes aegypti. Vitellogenin gene promoter was used in each transgenic strain to ectopically express either REL1 (REL1+ or REL2 (REL2+ in a sex, tissue, and stage specific manner. There was a significant change in the transcript abundance of 297 (79 up- and 218 down-regulated and 299 (123 up- and 176 down-regulated genes in fat bodies of REL1+ and REL2+, respectively. Over half of the induced genes had predicted functions in immunity, and a large group of these was co-regulated by REL1 and REL2. By generating a hybrid transgenic strain, which ectopically expresses both REL1 and REL2, we have shown a synergistic action of these NF-κB factors in activating immune genes. The REL1+ immune transcriptome showed a significant overlap with that of cactus (RNAi-depleted mosquitoes (50%. In contrast, the REL2+ -regulated transcriptome differed from the relatively small group of gene transcripts regulated by RNAi depletion of a putative inhibitor of the IMD pathway, caspar (35 up- and 140 down-regulated, suggesting that caspar contributes to regulation of a subset of IMD-pathway controlled genes. Infections of the wild type Ae. aegypti with Plasmodium gallinaceum elicited the transcription of a distinct subset of immune genes (76 up- and 25 down-regulated relative to that observed in REL1+ and REL2+ mosquitoes. Considerable overlap was observed between the fat body transcriptome of Plasmodium-infected mosquitoes and that of mosquitoes with transiently depleted PIAS, an inhibitor of the JAK-STAT pathway. PIAS gene silencing reduced Plasmodium proliferation in Ae. aegypti, indicating

  12. EFFICACY OF SOME COMMON AQUARIUM FISHES AS BIOCONTROL AGENT OF PREADULT MOSQUITOES

    Directory of Open Access Journals (Sweden)

    A. Ghosh

    2012-10-01

    Full Text Available Predation experiment using Betta splendens, Pseudotropheus tropheops, Osphronemus gorami and Pterophyllum scalare   were conducted against IVth instar Anopheline larvae and pupae with varying prey and predator densities. Ranking of individual predatory efficacy showed the sequence: P. tropheops > B. splendens > O. gorami > P. scalare against larva/form and B. splendens > O. gorami > P. tropheops > P. scalare against pupal form of Anopheles stephensi during 24 hours experiment in laboratory condition. Predation under co-existence in interspecific and intraspecific combinations revealed the significance of predatory efficacy with reference to prey density and water volume (search area.

  13. [A mosquito net for everyone in 2010].

    Science.gov (United States)

    Pays, J-F

    2010-10-01

    At less than two hundred days of the 2010 deadline for the "Roll Back Malaria" initiative which committed itself to reduce by half, before that date, mortality due to malaria in the world and relying on the latest WHO reports pointing out, in Africa, major shortcomings concerning the accessibility to treatment combinations consisting of artemisinin and on the acknowledged fact that an insufficient number of pregnant women receive an intermittent treatment, the author notes that a coverage, so-called universal, with the use of long action insecticide treated mosquito nets has become the Grail of the battle against malaria, with the perverse effects entailed, namely that of blinding realities or throwing discredit on other types of possible interventions that are not consistent with an accounting logic. He also notes that the average figure of estimated deaths due to malaria was at a quasi stagnation in 2008 and that the lives of 34,000 African children of less than 5 years of age saved between 2006 and 2008 was achieved in the context of the reduction in infant mortality resulting from a series of causes among which it is impossible to individualise malaria with certainty. He finally points out that Eritrea, Rwanda, Zambia, São Tome y Principe and the Tanzanian island of Zanzibar which quite regularly serve as showcases to RBM and UNICEF and which report spectacular progress in the field of prevention of malaria accompanied by a parallel reduction in its mortality, are, for different reasons, far from being representative of the totality of African countries and that they should be considered as exceptions rather than examples to be exploited without restraint. On the other hand, the author considers that deluding the grand public into thinking that a few watchwords, slogans and simple, even simplistic, ideas would enable eradicating malaria given that large sums of money are made available, is not quite honest and may finally prove to be dangerous. He warns

  14. Controle de vetores utilizando mosquitos geneticamente modificados Control de vectores utilizando mosquitos genéticamente modificados Control of vector populations using genetically modified mosquitoes

    Directory of Open Access Journals (Sweden)

    André Barreto Bruno Wilke

    2009-10-01

    Full Text Available Formas químicas de controle de mosquitos vetores são ineficazes, levando ao desenvolvimento de novas estratégias. Assim, foi realizada revisão das estratégias de controle genético de populações de mosquitos vetores baseada na técnica do inseto estéril. Uma delas consiste na liberação de machos esterilizados por radiação, a outra, na integração de um gene letal dominante associado a um promotor específico de fêmeas imaturas. Entre as vantagens sobre outras técnicas biológicas e químicas de controle de vetores estão: alta especificidade, não prejudicial ao meio ambiente, baixo custo de produção e alta eficácia. O uso desta técnica de modificação genética pode vir a ser uma importante ferramenta do manejo integrado de vetores.Formas químicas de control de mosquitos vectores son ineficaces, llevando al desarrollo de nuevas estrategias. Así, fue realizada revisión de las estrategias de control genético de poblaciones de mosquitos vectores basada en la técnica del insecto estéril. Una de ellas consiste en la liberación de machos esterilizados por radiación, la otra, en la integración de un gen letal dominante asociado a un promotor específico de hembras inmaduras. Entre las ventajas sobre otras técnicas biológicas y químicas de control de vectores están: la alta especificidad, no prejudicial al ambiente, bajo costo de producción y alta eficiencia. El uso de esta técnica de modificación genética puede ser una importante herramienta del manejo integrado de vectores.The ineffectiveness of current strategies for chemical control of mosquito vectors raises the need for developing novel approaches. Thus, we carried out a literature review of strategies for genetic control of mosquito populations based on the sterile insect technique. One of these strategies consists of releasing radiation-sterilized males into the population; another, of integrating a dominant lethal gene under the control of a specific

  15. Reproductive phase locking of mosquito populations in response to rainfall frequency.

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    Jeffrey Shaman

    Full Text Available The frequency of moderate to heavy rainfall events is projected to change in response to global warming. Here we show that these hydrologic changes may have a profound effect on mosquito population dynamics and rates of mosquito-borne disease transmission. We develop a simple model, which treats the mosquito reproductive cycle as a phase oscillator that responds to rainfall frequency forcing. This model reproduces observed mosquito population dynamics and indicates that mosquito-borne disease transmission can be sensitive to rainfall frequency. These findings indicate that changes to the hydrologic cycle, in particular the frequency of moderate to heavy rainfall events, could have a profound effect on the transmission rates of some mosquito-borne diseases.

  16. National Mosquito (Diptera: Culicidae) Survey in The Netherlands 2010-2013.

    Science.gov (United States)

    Ibañez-Justicia, A; Stroo, A; Dik, M; Beeuwkes, J; Scholte, E J

    2015-03-01

    From 2010 onwards, a nationwide mosquito monitoring scheme has been conducted in The Netherlands with the aim of gaining crucial information about mosquito (Diptera: Culicidae) species composition, geographical distributions, biodiversity, and habitat preferences. The results of this study are based on 778 randomly sampled mosquito locations. These are divided into three main habitat types: urban, rural-agricultural, and natural areas. Twenty-seven mosquito species were found: 26 indigenous and 1 exotic, Aedes japonicus japonicus (Theobald, 1901). The preliminary results are presented here, with details of their species distribution and seasonality. Monitoring the temporal and spatial distribution of mosquitoes is an essential step in the risk analysis of emerging mosquito-borne diseases.

  17. Bacteria as a source of oviposition attractant for Aedes aegypti mosquitoes.

    Science.gov (United States)

    Arbaoui, A A; Chua, T H

    2014-03-01

    Since a safe and effective mass vaccination program against dengue fever is not presently available, a good way to prevent and control dengue outbreaks depends mainly on controlling the mosquito vectors. Aedes aegypti mosquito populations can be monitored and reduced by using ovitraps baited with organic infusions. A series of laboratory experiments were conducted which demonstrated that the bacteria in bamboo leaf infusion produce volatile attractants and contact chemical stimulants attractive to the female mosquitoes. The results showed that the female mosquitoes laid most of their eggs (59.9 ± 8.1 vs 2.9 ± 2.8 eggs, PAedes mosquitoes. Aedes aegypti laid significantly more eggs (63.3 ± 6.5 vs 3.1 ± 2.4 eggs, P<0.001) in bacteria suspension compared to sterile R2A medium. Our results suggest microbial activity has a role in the production of odorants that mediate the oviposition response of gravid mosquitoes.

  18. Larvicidal activity of neem oil (Azadirachta indica formulation against mosquitoes

    Directory of Open Access Journals (Sweden)

    Dua Virendra K

    2009-06-01

    Full Text Available Abstract Background Mosquitoes transmit serious human diseases, causing millions of deaths every year. Use of synthetic insecticides to control vector mosquitoes has caused physiological resistance and adverse environmental effects in addition to high operational cost. Insecticides of botanical origin have been reported as useful for control of mosquitoes. Azadirachta indica (Meliaceae and its derived products have shown a variety of insecticidal properties. The present paper discusses the larvicidal activity of neem-based biopesticide for the control of mosquitoes. Methods Larvicidal efficacy of an emulsified concentrate of neem oil formulation (neem oil with polyoxyethylene ether, sorbitan dioleate and epichlorohydrin developed by BMR & Company, Pune, India, was evaluated against late 3rd and early 4th instar larvae of different genera of mosquitoes. The larvae were exposed to different concentrations (0.5–5.0 ppm of the formulation along with untreated control. Larvicidal activity of the formulation was also evaluated in field against Anopheles, Culex, and Aedes mosquitoes. The formulation was diluted with equal volumes of water and applied @ 140 mg a.i./m2 to different mosquito breeding sites with the help of pre calibrated knapsack sprayer. Larval density was determined at pre and post application of the formulation using a standard dipper. Results Median lethal concentration (LC50 of the formulation against Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti was found to be 1.6, 1.8 and 1.7 ppm respectively. LC50 values of the formulation stored at 26°C, 40°C and 45°C for 48 hours against Ae. aegypti were 1.7, 1.7, 1.8 ppm while LC90 values were 3.7, 3.7 and 3.8 ppm respectively. Further no significant difference in LC50 and LC90 values of the formulation was observed against Ae. aegypti during 18 months storage period at room temperature. An application of the formulation at the rate of 140 mg a.i./m2 in different breeding

  19. Mosquito population dynamics from cellular automata-based simulation

    Science.gov (United States)

    Syafarina, Inna; Sadikin, Rifki; Nuraini, Nuning

    2016-02-01

    In this paper we present an innovative model for simulating mosquito-vector population dynamics. The simulation consist of two stages: demography and dispersal dynamics. For demography simulation, we follow the existing model for modeling a mosquito life cycles. Moreover, we use cellular automata-based model for simulating dispersal of the vector. In simulation, each individual vector is able to move to other grid based on a random walk. Our model is also capable to represent immunity factor for each grid. We simulate the model to evaluate its correctness. Based on the simulations, we can conclude that our model is correct. However, our model need to be improved to find a realistic parameters to match real data.

  20. Zika virus: Endemic and epidemic ranges of Aedes mosquito transmission.

    Science.gov (United States)

    Attaway, David F; Waters, Nigel M; Geraghty, Estella M; Jacobsen, Kathryn H

    As evidence linking Zika virus with serious health complications strengthens, public health officials and clinicians worldwide need to know which locations are likely to be at risk for autochthonous Zika infections. We created risk maps for epidemic and endemic Aedes-borne Zika virus infections globally using a predictive analysis method that draws on temperature, precipitation, elevation, land cover, and population density variables to identify locations suitable for mosquito activity seasonally or year-round. Aedes mosquitoes capable of transmitting Zika and other viruses are likely to live year-round across many tropical areas in the Americas, Africa, and Asia. Our map provides an enhanced global projection of where vector control initiatives may be most valuable for reducing the risk of Zika virus and other Aedes-borne infections.

  1. Environmental management of mosquito-borne viruses in Rhode Island

    Science.gov (United States)

    Ginsberg, Howard S.; Gettman, Alan; Becker, Elisabeth; Bandyopadhyay, Ananda S.; LeBrun, Roger A.

    2013-01-01

    West Nile Virus (WNV) and Eastern Equine Encephalitis Virus (EEEV) are both primarily bird viruses, which can be transmitted by several mosquito species. Differences in larval habitats, flight, and biting patterns of the primary vector species result in substantial differences in epidemiology, with WNV more common, primarily occurring in urban areas, and EEEV relatively rare, typically occurring near swamp habitats. The complex transmission ecology of these viruses complicates prediction of disease outbreaks. The Rhode Island Department of Environmental Management (DEM) and Department of Health (DoH) provide prevention assistance to towns and maintain a mosquito surveillance program to identify potential disease risk. Responses to potential outbreaks follow a protocol based on surveillance results, assessment of human risk, and technical consultation.

  2. Taxonomy Icon Data: yellow fever mosquito [Taxonomy Icon

    Lifescience Database Archive (English)

    Full Text Available yellow fever mosquito Aedes aegypti Arthropoda Aedes_aegypti_L.png Aedes_aegypti_NL.png Aedes_aegypt...i_S.png Aedes_aegypti_NS.png http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti...&t=L http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti&t=NL http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegyp...ti&t=S http://biosciencedbc.jp/taxonomy_icon/icon.cgi?i=Aedes+aegypti&t=NS ...

  3. Plasmodium activates the innate immune response of Anopheles gambiae mosquitoes.

    OpenAIRE

    Richman, A M; Dimopoulos, G; Seeley, D; Kafatos, F C

    1997-01-01

    Innate immune-related gene expression in the major disease vector mosquito Anopheles gambiae has been analyzed following infection by the malaria parasite, Plasmodium berghei. Substantially increased levels of mRNAs encoding the antibacterial peptide defensin and a putative Gram-negative bacteria-binding protein (GNBP) are observed 20-30 h after ingestion of an infected blood-meal, at a time which indicates that this induction is a response to parasite invasion of the midgut epithelium. The i...

  4. Carbohydrate metabolism in the mosquito pathogen Bacillus sphaericus 2362.

    OpenAIRE

    Russell, B L; Jelley, S A; Yousten, A A

    1989-01-01

    Bacillus sphaericus 2362 is pathogenic for mosquito larvae and is being considered for large-scale production as a larvicide. The inability of the bacteria to metabolize carbohydrates requires that they be grown on proteinaceous media. This bacterium was found to be unable to transport glucose or sucrose into the cell, and it lacked glucokinase and hexokinase activity. In addition, it lacked phosphoglucose isomerase, phosphofructokinase, and glucose 6-phosphate dehydrogenase, which are early ...

  5. Mosquito larvicidal activity of Solanum nigrum berry extracts

    OpenAIRE

    Rawani, Anjali; Chowdhury, Nandita; Ghosh, Anupam; Laskar, Subrata; Chandra, Goutam

    2013-01-01

    Phytochemicals are widely used as biocontrol agent against vector mosquitoes. The present study was undertaken to isolate and evaluate the mosquitocidal activity of various extracts of berries of S. nigrum against Culex quinquefasciatus. Crude and chloroform: methanol (1:1, v/v) extracts of fresh, mature, green berries of S. nigrum were tested against Cx. quinquefasciatus. The lethal concentration was determined and the chemical nature of the active substance was evaluated. A qualitative phyt...

  6. Molecular identification of mosquitoes (Diptera: Culicidae) in southeastern Australia.

    Science.gov (United States)

    Batovska, Jana; Blacket, Mark J; Brown, Karen; Lynch, Stacey E

    2016-05-01

    DNA barcoding is a modern species identification technique that can be used to distinguish morphologically similar species, and is particularly useful when using small amounts of starting material from partial specimens or from immature stages. In order to use DNA barcoding in a surveillance program, a database containing mosquito barcode sequences is required. This study obtained Cytochrome Oxidase I (COI) sequences for 113 morphologically identified specimens, representing 29 species, six tribes and 12 genera; 17 of these species have not been previously barcoded. Three of the 29 species ─ Culex palpalis, Macleaya macmillani, and an unknown species originally identified as Tripteroides atripes ─ were initially misidentified as they are difficult to separate morphologically, highlighting the utility of DNA barcoding. While most species grouped separately (reciprocally monophyletic), the Cx. pipiens subgroup could not be genetically separated using COI. The average conspecific and congeneric p-distance was 0.8% and 7.6%, respectively. In our study, we also demonstrate the utility of DNA barcoding in distinguishing exotics from endemic mosquitoes by identifying a single intercepted Stegomyia aegypti egg at an international airport. The use of DNA barcoding dramatically reduced the identification time required compared with rearing specimens through to adults, thereby demonstrating the value of this technique in biosecurity surveillance. The DNA barcodes produced by this study have been uploaded to the 'Mosquitoes of Australia-Victoria' project on the Barcode of Life Database (BOLD), which will serve as a resource for the Victorian Arbovirus Disease Control Program and other national and international mosquito surveillance programs.

  7. Insect Repellents: Modulators of Mosquito Odorant Receptor Activity

    Science.gov (United States)

    2010-08-01

    molecular pathways through allosteric regulation of various proteins including proteases [39,40], the cannabinoid receptor 1 (CB1) [41], the a7 nicotinic...41. Price MR, Baillie GL, Thomas A, Stevenson LA, Easson M, et al. (2005) Allosteric modulation of the cannabinoid CB1 receptor . Mol Pharmacol 68...Insect Repellents: Modulators of Mosquito Odorant Receptor Activity Jonathan D. Bohbot, Joseph C. Dickens* Invasive Insect Biocontrol and Behavior

  8. Nationwide inventory of mosquito biodiversity (Diptera: Culicidae) in Belgium, Europe.

    Science.gov (United States)

    Versteirt, V; Boyer, S; Damiens, D; De Clercq, E M; Dekoninck, W; Ducheyne, E; Grootaert, P; Garros, C; Hance, T; Hendrickx, G; Coosemans, M; Van Bortel, W

    2013-04-01

    To advance our restricted knowledge on mosquito biodiversity and distribution in Belgium, a national inventory started in 2007 (MODIRISK) based on a random selection of 936 collection points in three main environmental types: urban, rural and natural areas. Additionally, 64 sites were selected because of the risk of importing a vector or pathogen in these sites. Each site was sampled once between May and October 2007 and once in 2008 using Mosquito Magnet Liberty Plus traps. Diversity in pre-defined habitat types was calculated using three indices. The association between species and environmental types was assessed using a correspondence analysis. Twenty-three mosquito species belonging to traditionally recognized genera were found, including 21 indigenous and two exotic species. Highest species diversity (Simpson 0.765) and species richness (20 species) was observed in natural areas, although urban sites scored also well (Simpson 0.476, 16 species). Four clusters could be distinguished based on the correspondence analysis. The first one is related to human modified landscapes (such as urban, rural and industrial sites). A second is composed of species not associated with a specific habitat type, including the now widely distributed Anopheles plumbeus. A third group includes species commonly found in restored natural or bird migration areas, and a fourth cluster is composed of forest species. Outcomes of this study demonstrate the effectiveness of the designed sampling scheme and support the choice of the trap type. Obtained results of this first country-wide inventory of the Culicidae in Belgium may serve as a basis for risk assessment of emerging mosquito-borne diseases.

  9. Crab Hole Mosquito Blues—The Story

    Centers for Disease Control (CDC) Podcasts

    2011-05-12

    This podcast reports on a humorous song that takes a look at a very serious human and equine disease. Written and performed by the MARU Health Angels Band, Bill Dietz, director of the Division of Nutrition, Physical Activity and Obesity at CDC, talks about the song, "Crab Hole Mosquito Blues", and the history behind it.  Created: 5/12/2011 by National Center for Emerging Zoonotic and Infectious Diseases (NCEZID).   Date Released: 5/23/2011.

  10. Zika mosquito vectors: the jury is still out

    OpenAIRE

    Leal, Walter S.

    2016-01-01

    After a 40-year hiatus, the International Congress of Entomology (ICE 2016) convened in Orlando, Florida (September 25-30, 2016). One of the symposia at ICE 2016, the Zika Symposium, covered multiple aspects of the Zika epidemic, including epidemiology, sexual transmission, genetic tools for reducing transmission, and particularly vector competence. While there was a consensus among participants that the yellow fever mosquito, Aedes aegypti, is a vector of the Zika virus, there is growing evi...

  11. Field Evaluation of Four Spatial Repellent Devices Against Arkansas Rice-Land Mosquitoes

    Science.gov (United States)

    2014-03-01

    FIELD EVALUATION OF FOUR SPATIAL REPELLENT DEVICES AGAINST ARKANSAS RICE-LAND MOSQUITOES DAVID A. DAME,1 MAX V. MEISCH,2 CAROLYN N. LEWIS,2 DANIEL L... mosquitoes to locate a host. There are many commercially available spatial repellent products currently on the market. These products include...a large rice growing area where late-spring and summer agricultural irriga- tion generates dense mosquito populations. Spatial repellent devices

  12. Chikungunya Virus Replication in Salivary Glands of the Mosquito Aedes albopictus

    Directory of Open Access Journals (Sweden)

    Anubis Vega-Rúa

    2015-11-01

    Full Text Available Chikungunya virus (CHIKV is an emerging arbovirus transmitted to humans by mosquitoes such as Aedes albopictus. To be transmitted, CHIKV must replicate in the mosquito midgut, then disseminate in the hemocele and infect the salivary glands before being released in saliva. We have developed a standardized protocol to visualize viral particles in the mosquito salivary glands using transmission electron microscopy. Here we provide direct evidence for CHIKV replication and storage in Ae. albopictus salivary glands.

  13. Chikungunya Virus Replication in Salivary Glands of the Mosquito Aedes albopictus.

    Science.gov (United States)

    Vega-Rúa, Anubis; Schmitt, Christine; Bonne, Isabelle; Krijnse Locker, Jacomine; Failloux, Anna-Bella

    2015-11-17

    Chikungunya virus (CHIKV) is an emerging arbovirus transmitted to humans by mosquitoes such as Aedes albopictus. To be transmitted, CHIKV must replicate in the mosquito midgut, then disseminate in the hemocele and infect the salivary glands before being released in saliva. We have developed a standardized protocol to visualize viral particles in the mosquito salivary glands using transmission electron microscopy. Here we provide direct evidence for CHIKV replication and storage in Ae. albopictus salivary glands.

  14. Spatial and Temporal Analysis of Alphavirus Replication and Assembly in Mammalian and Mosquito Cells

    OpenAIRE

    Joyce Jose; Aaron B. Taylor; Kuhn, Richard J.; Dermody, Terence S.

    2017-01-01

    Sindbis virus (SINV [genus Alphavirus, family Togaviridae]) is an enveloped, mosquito-borne virus. Alphaviruses cause cytolytic infections in mammalian cells while establishing noncytopathic, persistent infections in mosquito cells. Mosquito vector adaptation of alphaviruses is a major factor in the transmission of epidemic strains of alphaviruses. Though extensive studies have been performed on infected mammalian cells, the morphological and structural elements of alphavirus replication and ...

  15. Spatial and Temporal Analysis of Alphavirus Replication and Assembly in Mammalian and Mosquito Cells

    OpenAIRE

    Jose, Joyce; Aaron B. Taylor; Kuhn, Richard J.

    2017-01-01

    ABSTRACT Sindbis virus (SINV [genus Alphavirus, family Togaviridae]) is an enveloped, mosquito-borne virus. Alphaviruses cause cytolytic infections in mammalian cells while establishing noncytopathic, persistent infections in mosquito cells. Mosquito vector adaptation of alphaviruses is a major factor in the transmission of epidemic strains of alphaviruses. Though extensive studies have been performed on infected mammalian cells, the morphological and structural elements of alphavirus replica...

  16. Role of Cellular Components of Mosquito Cells in Viral Replication and Transmission.

    Science.gov (United States)

    1981-03-17

    replicating in mosquito cells, experiments similar to those described above were conducted employing Eastern equine encephalitis virus ( alphavirus ...7 D-R126 612 ROLE OF CELLULAR COMPONENTS OF MOSQUITO CELLS IN VIRAL 1/1 REPLICATION AND TRANSMISSION(U) INDIANA UNIV AT INDIANAPOLIS SCHOOL OF...MOSQUITO CELLS IN VIRAL REPLICATION AND TRANSMISSION Annual Report Final Report Robert H. Schloemer March 17, 1981 Supported by U.S. Army Medical

  17. Suppression of RNA interference increases alphavirus replication and virus-associated mortality in Aedes aegypti mosquitoes

    Directory of Open Access Journals (Sweden)

    Geiss Brian J

    2009-03-01

    Full Text Available Abstract Background Arthropod-borne viruses (arboviruses can persistently infect and cause limited damage to mosquito vectors. RNA interference (RNAi is a mosquito antiviral response important in restricting RNA virus replication and has been shown to be active against some arboviruses. The goal of this study was to use a recombinant Sindbis virus (SINV; family Togaviridae; genus Alphavirus that expresses B2 protein of Flock House virus (FHV; family Nodaviridae; genus Alphanodavirus, a protein that inhibits RNAi, to determine the effects of linking arbovirus infection with RNAi inhibition. Results B2 protein expression from SINV (TE/3'2J inhibited the accumulation of non-specific small RNAs in Aedes aegypti mosquito cell culture and virus-specific small RNAs both in infected cell culture and Ae. aegypti mosquitoes. More viral genomic and subgenomic RNA accumulated in cells and mosquitoes infected with TE/3'2J virus expressing B2 (TE/3'2J/B2 compared to TE/3'2J and TE/3'2J virus expressing GFP. TE/3'2J/B2 exhibited increased infection rates, dissemination rates, and infectious virus titers in mosquitoes following oral bloodmeal. Following infectious oral bloodmeal, significantly more mosquitoes died when TE/3'2J/B2 was ingested. The virus was 100% lethal following intrathoracic inoculation of multiple mosquito species and lethality was dose-dependent in Ae. aegypti. Conclusion We show that RNAi is active in Ae. aegypti cell culture and that B2 protein inhibits RNAi in mosquito cells when expressed by a recombinant SINV. Also, SINV more efficiently replicates in mosquito cells when RNAi is inhibited. Finally, TE/3'2J/B2 kills mosquitoes in a dose-dependent manner independent of infection route and mosquito species.

  18. Yellow fever vaccination centers: concurrent vaccinations and updates on mosquito biology.

    Science.gov (United States)

    Arya, Subhash C; Agarwal, Nirmala

    2012-09-01

    Mandatory visits to immunization centers that offer pre-travel Yellow fever vaccine to prospective travelers would be useful for briefing the basics of the biology of the mosquito responsible for Yellow fever spread. Pre- travel knowledge on the day-time rather the nocturnal biting habit of the mosquitoes of Aedes species would prevent from bites of the mosquitoes responsible for the spread of viruses causing Yellow fever, dengue or Chikungunya infection.

  19. Preliminary Analysis of Several Attractants and Spatial Repellents for the Mosquito, Aedes albopictus using an Olfactometer

    OpenAIRE

    Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

    2012-01-01

    Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Further...

  20. Some environmental and biological factors influencing the activity of entomopathogenic Bacillus on mosquito larvae in Brazil

    Directory of Open Access Journals (Sweden)

    R. A. G. B Consoli

    1995-02-01

    Full Text Available The influence of environmental and biological factors on the efficacy of Bacillus thuringiensis serovar israelensis and B. sphaericus as mosquito larvicides are reviewed. The importance of strain dependence, cultivating media/methods, mosquito species/specificity, formulations and their relation to mosquito feeding habits, as well as temperature, solar exposure, larval density and concomitant presence of other aquatic organisms are addressed with reference to the present status of knowledge in Brazil.

  1. The most common mosquitoes at Al- Rayyan municipality (Qatar state) and their potential for transmitting malaria

    OpenAIRE

    Ahmed, Rabab Ibrahim

    2015-01-01

    During the period from December 2014 to April 2015, a mosquito survey (Diptera: Culicidae) was conducted at Al Rayyan Municipality, western region of Qatar. The survey aimed to identify the most common mosquitoes species in the study area and assess their potential in transmitting malaria. In all, 37 collection sites were visited throughout the study period revealing 312 mosquitoes. Larvae were collected as well as adults. The pH of larvae breeding sites was also measured in the laboratory. A...

  2. Aedes triseriatus females transovarially-infected with La Crosse virus mate more efficiently than uninfected mosquitoes

    Science.gov (United States)

    Reese, Sara M.; Beaty, Meaghan K.; Gabitzsch, Elizabeth S.; Blair, Carol D.; Beaty, Barry J.

    2010-01-01

    The mating efficiencies of field-collected and laboratory-colonized Aedes triseriatus (Say) (Diptera: Culicidae) female mosquitoes transovarially-infected or uninfected with La Crosse virus (LACV) were compared. The females were placed in cages with age-matched males, and the insemination rates were determined daily by detection of sperm in the spermathecae. LACV-infected mosquitoes typically mated more quickly than uninfected mosquitoes. LACV load was not correlated with increased insemination. PMID:19769048

  3. Ecological Niche Modeling of Potential West Nile Virus Vector Mosquito Species in Iowa

    OpenAIRE

    2010-01-01

    Ecological niche modeling (ENM) algorithms, Maximum Entropy Species Distribution Modeling (Maxent) and Genetic Algorithm for Rule-set Prediction (GARP), were used to develop models in Iowa for three species of mosquito — two significant, extant West Nile virus (WNV) vectors (Culex pipiens L and Culex tarsalis Coquillett (Diptera: Culicidae)), and the nuisance mosquito, Aedes vexans Meigen (Diptera: Culicidae), a potential WNV bridge vector. Occurrence data for the three mosquito species from ...

  4. Exposure to Mosquito Coil Smoke May be a Risk Factor for Lung Cancer in Taiwan

    OpenAIRE

    Chen, Shu-Chen; Wong, Ruey-Hong; Shiu, Li-Jie; Chiou, Ming-Chih; Lee, Huei

    2008-01-01

    Background About 50% of lung cancer deaths in Taiwan are not related to cigarette smoking. Environmental exposure may play a role in lung cancer risk. Taiwanese households frequently burn mosquito coil at home to repel mosquitoes. The aim of this hospital-based case-control study was to determine whether exposure to mosquito coil smoke is a risk for lung cancer. Methods Questionnaires were administered to 147 primary lung cancer patients and 400 potential controls to ascertain demographic dat...

  5. Targeting gene expression to the female larval fat body of transgenic Aedes aegypti mosquitoes

    OpenAIRE

    TOTTEN, Daniel C.; Vuong, Mai; LITVINOVA, Oksana V.; Jinwal, Umesh K.; Gulia-Nuss, Monika; Harrell, Robert A.; Beneš, Helen

    2012-01-01

    As the fat body is a critical tissue for mosquito development, metamorphosis, immune and reproductive system function, characterization of regulatory modules targeting gene expression to the female mosquito fat body at distinct life stages is much needed for multiple, varied strategies for controlling vector-borne diseases such as dengue and malaria. The hexameric storage protein, Hexamerin-1.2, of the mosquito, Aedes atropalpus, is female-specific and uniquely expressed in the fat body of fo...

  6. An entomological review of invasive mosquitoes in Europe.

    Science.gov (United States)

    Medlock, J M; Hansford, K M; Versteirt, V; Cull, B; Kampen, H; Fontenille, D; Hendrickx, G; Zeller, H; Van Bortel, W; Schaffner, F

    2015-12-01

    Among the invasive mosquitoes registered all over the world, Aedes species are particularly frequent and important. As several of them are potential vectors of disease, they present significant health concerns for 21st century Europe. Five species have established in mainland Europe, with two (Aedes albopictus and Aedes japonicus) becoming widespread and two (Ae. albopictus and Aedes aegypti) implicated in disease transmission to humans in Europe. The routes of importation and spread are often enigmatic, the ability to adapt to local environments and climates are rapid, and the biting nuisance and vector potential are both an ecomonic and public health concern. Europeans are used to cases of dengue and chikungunya in travellers returning from the tropics, but the threat to health and tourism in mainland Europe is substantive. Coupled to that are the emerging issues in the European overseas territorities and this paper is the first to consider the impacts in the remoter outposts of Europe. If entomologists and public health authorities are to address the spread of these mosquitoes and mitigate their health risks they must first be prepared to share information to better understand their biology and ecology, and share data on their distribution and control successes. This paper focusses in greater detail on the entomological and ecological aspects of these mosquitoes to assist with the risk assessment process, bringing together a large amount of information gathered through the ECDC VBORNET project.

  7. Larval habitats of mosquito fauna in Osogbo metropolis, Southwestern Nigeria

    Institute of Scientific and Technical Information of China (English)

    Monsuru Adebayo Adeleke; Wasiu Olalekan Adebimpe; AbdulWasiu Oladele Hassan; Sunday Olukayode Oladejo; Ismail Olaoye; Ganiyu Olatunji Olatunde; Taiwo Adewole

    2013-01-01

    Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-borne diseases in Osogbo metropolis, Southwestern, Nigeria. Methods: All accessible larval habitats were surveyed between May and September, 2011 in Osogbo metropolis while Land Use/ Land cover of the city was analyzed using 2 Lansat Multispectral Scanner satellite imagery of SPOT 1986 and LANDSAT TM 2009. Results:A total of six species namely, Aedes aegypti, Aedes albopictus, Aedes vittatus, Anopheles gambiae complex, Culex quinquefasciatus and Eretmapodite chrysogaster were encountered during the study. The occurrence and contribution of disused tyres was significantly higher (P0.05). The accessible land use/land covered of the study area between 1986 and 2009 showed that the wet land coverage and settlement area increased from 0.19 to 9.09 hectare and 1.00 to 2.01 hectare respectively while the forest area decreased from 60.18 to 50.14 hectare. Conclusion: The contribution of the habitats coupled with the increasing rate of flooded environment which could provide ample breeding sites for mosquitoes call for sustained environmental sanitation and management in Osogbo metropolis.

  8. Distribution of mosquitoes in relation to urban landscape characteristics.

    Science.gov (United States)

    Gleiser, R M; Zalazar, L P

    2010-04-01

    The current global increase in prevalence of vector borne diseases, as well as an expansion of tropical infections to more temperate zones, justifies further studies on vector populations. Urban areas may favour viral transmission to humans through close contacts between the vectors and the vertebrate hosts, and also affecting mosquito populations by offering larval habitat, refuges and adequate microclimates to survive the winter. This work analyses the spatial distribution of potential vector mosquitoes in relation to landscape characteristics in an urban environment in a temperate climate region. Mosquitoes were trapped monthly from October 2005 to March 2006 in 25 sites within Córdoba city and suburbs with miniature light traps+CO2. Nine species were collected, and the most abundant were Culex quinquefasciatus (37.1%), C. apicinus (26.6%) and Aedes aegypti (13.9%). Species that may be involved in SLEv transmission were recorded throughout the sampling. C. quinquefasciatus was detected in 92% of the sites; however, only two sites showed consistently larger collections. The site of highest C. quinquefasciatus abundance was located within an area of high Saint Louis Encefalitis virus prevalence and risk of infection, further supporting this species involvement as a vector. Significant correlations were detected between land cover characteristics and abundance of C. apicinus, C. interfor and C. maxi that were consistent with previous knowledge about their larval habitat and domestic preferences, which may be useful for targeting vector control operations.

  9. Book review: Mosquito eradication: The story of killing Campto

    Science.gov (United States)

    Lapointe, Dennis

    2015-01-01

    In 1826, the paradise that was the Hawaiian Islands was changed forever when the first mosquito species was accidentally introduced to the island of Maui. Though it has not lived up to its potential as a vector of human disease in the islands, Culex quinquefasciatus and the avian pathogens it transmits laid waste to perhaps the world's most remarkable insular avifauna. Today the lowland native forests, once deafening with birdsong, are largely devoid of native birds and Cx. quinquefasciatus has become an inextricable part of our natural areas. In the Hawaiian Islands, the conservation community struggles to keep invasive species out and to control a number of species that have become naturalized. Despite the millions of dollars spent, these efforts never seem enough to slow the erosion of our native biota. The restoration and long-term preservation of Hawaiian forest birds depend on the nearly complete control of mosquito-borne avian disease, an obstacle that to many land managers appears insurmountable. To rally hope in Hawai`i, the conservation community needs to see a success. As a Pacific island, Hawai`i shares similar conservation problems with New Zealand and has often looked to that nation for innovation and inspiration. Mosquito Eradication: The Story of Killing Campto may be our latest inspiration.

  10. Mosquitoes of eastern Amazonian Ecuador: biodiversity, bionomics and barcodes

    Directory of Open Access Journals (Sweden)

    Yvonne-Marie Linton

    2013-01-01

    Full Text Available Two snapshot surveys to establish the diversity and ecological preferences of mosquitoes (Diptera: Culicidae in the terra firme primary rain forest surrounding the Tiputini Biodiversity Station in the UNESCO Yasuní Biosphere Reserve of eastern Amazonian Ecuador were carried out in November 1998 and May 1999. The mosquito fauna of this region is poorly known; the focus of this study was to obtain high quality link-reared specimens that could be used to unequivocally confirm species level diversity through integrated systematic study of all life stages and DNA sequences. A total of 2,284 specimens were preserved; 1,671 specimens were link-reared with associated immature exuviae, all but 108 of which are slide mounted. This study identified 68 unique taxa belonging to 17 genera and 27 subgenera. Of these, 12 are new to science and 37 comprise new country records. DNA barcodes [658-bp of the mtDNA cytochrome c oxidase ( COI I gene] are presented for 58 individuals representing 20 species and nine genera. DNA barcoding proved useful in uncovering and confirming new species and we advocate an integrated systematics approach to biodiversity studies in future. Associated bionomics of all species collected are discussed. An updated systematic checklist of the mosquitoes of Ecuador (n = 179 is presented for the first time in 60 years.

  11. Synergism between permethrin and propoxur against Culex quinquefasciatus mosquito larvae.

    Science.gov (United States)

    Corbel, V; Chandre, F; Darriet, F; Lardeux, F; Hougard, J-M

    2003-06-01

    To see if synergism occurs between carbamate and pyrethroid insecticides, we tested permethrin and propoxur as representatives of these two classes of compounds used for mosquito control. Larvicidal activity of both insecticides was assessed separately and together on a susceptible strain of the mosquito Culex quinquefasciatus (Diptera: Culicidae) by two methods. When mixed at a constant ratio (permethrin : propoxur 1 : 60 based on LC50) and tested at serial concentrations to plot dose/mortality regression, significant synergy occurred between them (co-toxicity coefficient = 2.2), not just an additive effect. For example, when the mixture gave 50% mortality, the same concentrations of permethrin and propoxur alone would have given merely 2 x 1% mortality. When a sublethal dose (LC0) of permethrin or propoxur was added to the other (range LC10-LC95), synergism occurred up to the LC80 level. Synergistic effects were attributed to the complementary modes of action by these two insecticide classes acting on different components of nerve impulse transmission. Apart from raising new possibilities for Culex control, it seems appropriate to consider using such mixtures or combinations for insecticide-treated mosquito nets in situations with insecticide-resistant Anopheles malaria vectors.

  12. Evolution of Mosquito-Based Arbovirus Surveillance Systems in Australia

    Directory of Open Access Journals (Sweden)

    Andrew F. van den Hurk

    2012-01-01

    Full Text Available Control of arboviral disease is dependent on the sensitive and timely detection of elevated virus activity or the identification of emergent or exotic viruses. The emergence of Japanese encephalitis virus (JEV in northern Australia revealed numerous problems with performing arbovirus surveillance in remote locations. A sentinel pig programme detected JEV activity, although there were a number of financial, logistical, diagnostic and ethical limitations. A system was developed which detected viral RNA in mosquitoes collected by solar or propane powered CO2-baited traps. However, this method was hampered by trap-component malfunction, microbial contamination and large mosquito numbers which overwhelmed diagnostic capabilities. A novel approach involves allowing mosquitoes within a box trap to probe a sugar-baited nucleic-acid preservation card that is processed for expectorated arboviruses. In a longitudinal field trial, both Ross River and Barmah Forest viruses were detected numerous times from multiple traps over different weeks. Further refinements, including the development of unpowered traps and use of yeast-generated CO2, could enhance the applicability of this system to remote locations. New diagnostic technology, such as next generation sequencing and biosensors, will increase the capacity for recognizing emergent or exotic viruses, while cloud computing platforms will facilitate rapid dissemination of data.

  13. Evaluation of the control of mosquitoes with insect growth regulators.

    Science.gov (United States)

    Ho, C M; Wu, S H; Wu, C C

    1990-07-01

    In this study, the effectiveness of eight insect growth regulators (IGRs) (chlorfluazuron, diflubenzuron, EL-494, flufenoxuron, teflubenzuron, juglone, plumbagin and methoprene) against five mosquito vectors (Armigeres subalbatus, Aedes albopictus, Aedes aegypti, Culex tritaeniorhynchus, and Culex quinquefasciatus) was investigated in the laboratory. The EC50s of chlorfluazuron, diflubenzuron, EL-494, flufenoxuron, teflubenzuron, and methoprene against the five mosquitoes ranged from 0.0001 to 0.3 ppm and those of juglone and plumbagin from 3-25 ppm. The five mosquito species had similar tolerances to the test IGRs. At pH 5 to 9, the effectiveness of the first five chemicals was very stable. After ultraviolet irradiation or heat management (45 degrees C-60 degrees C), diflubenzuron and flufenoxuron were very stable. EL-494 was not stable when exposed to ultraviolet irradiation or heat. Under 0.1 ppm, teflubenzuron was not stable upon exposure to heat and chlorfluazuron and methoprene were not stable when exposed to ultraviolet irradiation. Piperonyl butoxide reduces the effectiveness of the five IGRs. Administration of diflubenzuron (1-5 ppm), flufenoxuron (0.025 ppm), and teflubenzuron (1-5 ppm) reduced Culex quinquefasciatus larvae in ditches by 40-90%. The administration of diflubenzuron (0.5 ppm) to containers reduced 97% of the Aedes albopictus larvae.

  14. Mosquito Fauna (Diptera: Culicidae of Hamedan County, Western Iran.

    Directory of Open Access Journals (Sweden)

    Amir Hossein Zahirnia

    2014-12-01

    Full Text Available This study aimed to identify and determine the larval and adult mosquitoes (Culicidae fauna in Hamedan County, western Iran.It was a cross-sectional study which took place in four area of the Hamedan County. Sampling methods for larvae, pupae and adults were dipping, hand catch, night catch and total catch. Larvae and adult mosquitoes collected and were sent to laboratory of Medical Entomology, Hamedan University of Medical Sciences, Hamedan, Iran for further identification to species level to determination of fauna. Data analysis was performed using SPSS software version19.Three genera and eight species of family Culicidae were collected and identified in Hamedan County, Hamedan Province, West Iran, during May to October 2013. These species included: Culex theileri, Cx. pipiens, Cx. antennatus, Culiseta subochrea, Cs. langiareolata, Anopheles superpictus, An. maculipennis and An. stephensi. The species Cx. antennatus and An. stephensi were reported for the first time in Hamedan County.An. stephensi and Cx. antennatus caught had not been previously recorded in Hamedan Province. Due to vast agricultural activities in the province which provides suitable environment for the establishment of various species of mosquitoes and since many of them are potential vectors of human and domesticated animal pathogens, their ecology needs to be studied extensively.

  15. Nature, Nurture and Evolution of Intra-Species Variation in Mosquito Arbovirus Transmission Competence

    Directory of Open Access Journals (Sweden)

    Walter J. Tabachnick

    2013-01-01

    Full Text Available Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses. Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature and environmental (nurture factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

  16. Tires as larval habitats for mosquitoes (Diptera: Culicidae) in southern Manitoba, Canada.

    Science.gov (United States)

    McMahon, T J Scott; Galloway, Terry D; Anderson, Robert A

    2008-06-01

    In 2003, a survey at waste management grounds and tire dealerships was conducted to determine the species composition of mosquitoes in tires in southern Manitoba, Canada. Over 25% of the 1,142 tires sampled contained a total of 32,474 mosquito larvae and pupae. Culex restuans made up at least 95% of the larvae collected for each month of the summer. Culiseta inornata and Culex tarsalis reached their greatest numbers in July and August, respectively, though they were never abundant. Ochlerotatus triseriatus was also found but never reached more than 1% of the total larvae collected in any given month. Mosquito prevalence was more than three times greater in August (36.1%) than in June (11.7%). Orientation affected prevalence of mosquitoes in tires: 31.4% of vertical tires (tires standing on their treads) contained mosquitoes, whereas mosquitoes were found in only 18.9% of horizontal tires (tires parallel to the ground). Tires in the eastern region of Manitoba contained mosquitoes more often (61.7%), irrespective of date, than Winnipeg (25.9%), the central region (29.1%), or the western region (19.8%). Mosquito prevalence was similar across three size categories of tires, car tires (18.8%), truck tires (19.8%), and semi-trailer tires (26.7%), though tractor tires (47.8%) contained significantly more mosquitoes than tires in the other categories.

  17. Bacterial communities associated with culex mosquito larvae and two emergent aquatic plants of bioremediation importance.

    Science.gov (United States)

    Duguma, Dagne; Rugman-Jones, Paul; Kaufman, Michael G; Hall, Michael W; Neufeld, Josh D; Stouthamer, Richard; Walton, William E

    2013-01-01

    Microbes are important for mosquito nutrition, growth, reproduction and control. In this study, we examined bacterial communities associated with larval mosquitoes and their habitats. Specifically, we characterized bacterial communities associated with late larval instars of the western encephalitis mosquito (Culextarsalis), the submerged portions of two emergent macrophytes (California bulrush, Schoenoplectuscalifornicus and alkali bulrush, Schoenoplectusmaritimus), and the associated water columns to investigate potential differential use of resources by mosquitoes in different wetland habitats. Using next-generation sequence data from 16S rRNA gene hypervariable regions, the alpha diversity of mosquito gut microbial communities did not differ between pond mesocosms containing distinct monotypic plants. Proteobacteria, dominated by the genus Thorsellia (Enterobacteriaceae), was the most abundant phylum recovered from C. tarsalis larvae. Approximately 49% of bacterial OTUs found in larval mosquitoes were identical to OTUs recovered from the water column and submerged portions of the two bulrushes. Plant and water samples were similar to one another, both being dominated by Actinobacteria, Bacteroidetes, Cyanobacteria, Proteobacteria and Verrucomicrobia phyla. Overall, the bacterial communities within C. tarsalis larvae were conserved and did not change across sampling dates and between two distinct plant habitats. Although Thorsellia spp. dominated mosquito gut communities, overlap of mosquito gut, plant and water-column OTUs likely reveal the effects of larval feeding. Future research will investigate the role of the key indicator groups of bacteria across the different developmental stages of this mosquito species.

  18. Predation by odonates depresses mosquito abundance in water-filled tree holes in Panama.

    Science.gov (United States)

    Fincke, Ola M; Yanoviak, Stephen P; Hanschu, Richard D

    1997-10-01

    In the lowland moist forest of Barro Colorado Island (BCI), Panama, larvae of four common species of odonates, a mosquito, and a tadpole are the major predators in water-filled tree holes. Mosquito larvae are their most common prey. Holes colonized naturally by predators and prey had lower densities of mosquitoes if odonates were present than if they were absent. Using artificial tree holes placed in the field, we tested the effects of odonates on their mosquito prey while controlling for the quantity and species of predator, hole volume, and nutrient input. In large and small holes with low nutrient input, odonates depressed the number of mosquitoes present and the number that survived to pupation. Increasing nutrient input (and consequently, mosquito abundance) to abnormally high levels dampened the effect of predation when odonates were relatively small. However, the predators grew faster with higher nutrients, and large larvae in all three genera reduced the number of mosquitoes surviving to pupation, even though the abundance of mosquito larvae remained high. Size-selective predation by the odonates is a likely explanation for this result; large mosquito larvae were less abundant in the predator treatment than in the controls. Because species assemblages were similar between natural and artificial tree holes, our results suggest that odonates are keystone species in tree holes on BCI, where they are the most common large predators.

  19. Nature, nurture and evolution of intra-species variation in mosquito arbovirus transmission competence.

    Science.gov (United States)

    Tabachnick, Walter J

    2013-01-11

    Mosquitoes vary in their competence or ability to transmit arthropod-borne viruses (arboviruses). Many arboviruses cause disease in humans and animals. Identifying the environmental and genetic causes of variation in mosquito competence for arboviruses is one of the great challenges in public health. Progress identifying genetic (nature) and environmental (nurture) factors influencing mosquito competence for arboviruses is reviewed. There is great complexity in the various traits that comprise mosquito competence. The complex interactions between environmental and genetic factors controlling these traits and the factors shaping variation in Nature are largely unknown. The norms of reaction of specific genes influencing competence, their distributions in natural populations and the effects of genetic polymorphism on phenotypic variation need to be determined. Mechanisms influencing competence are not likely due to natural selection because of the direct effects of the arbovirus on mosquito fitness. More likely the traits for mosquito competence for arboviruses are the effects of adaptations for other functions of these competence mechanisms. Determining these other functions is essential to understand the evolution and distributions of competence for arboviruses. This information is needed to assess risk from mosquito-borne disease, predict new mosquito-arbovirus systems, and provide novel strategies to mitigate mosquito-borne arbovirus transmission.

  20. The Role of Innate Immunity in Conditioning Mosquito Susceptibility to West Nile Virus

    Directory of Open Access Journals (Sweden)

    Abhishek N. Prasad

    2013-12-01

    Full Text Available Arthropod-borne viruses (arboviruses represent an emerging threat to human and livestock health globally. In particular, those transmitted by mosquitoes present the greatest challenges to disease control efforts. An understanding of the molecular basis for mosquito innate immunity to arbovirus infection is therefore critical to investigations regarding arbovirus evolution, virus-vector ecology, and mosquito vector competence. In this review, we discuss the current state of understanding regarding mosquito innate immunity to West Nile virus. We draw from the literature with respect to other virus-vector pairings to attempt to draw inferences to gaps in our knowledge about West Nile virus and relevant vectors.

  1. Modeling Occurrence of Urban Mosquitos Based on Land Use Types and Meteorological Factors in Korea.

    Science.gov (United States)

    Kwon, Yong-Su; Bae, Mi-Jung; Chung, Namil; Lee, Yeo-Rang; Hwang, Suntae; Kim, Sang-Ae; Choi, Young Jean; Park, Young-Seuk

    2015-10-20

    Mosquitoes are a public health concern because they are vectors of pathogen, which cause human-related diseases. It is well known that the occurrence of mosquitoes is highly influenced by meteorological conditions (e.g., temperature and precipitation) and land use, but there are insufficient studies quantifying their impacts. Therefore, three analytical methods were applied to determine the relationships between urban mosquito occurrence, land use type, and meteorological factors: cluster analysis based on land use types; principal component analysis (PCA) based on mosquito occurrence; and three prediction models, support vector machine (SVM), classification and regression tree (CART), and random forest (RF). We used mosquito data collected at 12 sites from 2011 to 2012. Mosquito abundance was highest from August to September in both years. The monitoring sites were differentiated into three clusters based on differences in land use type such as culture and sport areas, inland water, artificial grasslands, and traffic areas. These clusters were well reflected in PCA ordinations, indicating that mosquito occurrence was highly influenced by land use types. Lastly, the RF represented the highest predictive power for mosquito occurrence and temperature-related factors were the most influential. Our study will contribute to effective control and management of mosquito occurrences.

  2. Current and potential impacts of mosquitoes and the pathogens they vector in the Pacific region

    Science.gov (United States)

    LaPointe, Dennis

    2007-01-01

    Mosquitoes and the pathogens they transmit are ubiquitous throughout most of the temperate and tropical regions of the world. The natural and pre-European distribution and diversity of mosquitoes and mosquito-borne diseases throughout much of the Pacific region, however, depicts a depauperate and relatively benign fauna reinforcing the dream of “paradise regained”. In the central and South Pacific few mosquito species were able to colonize the remotest islands and atolls. Native mosquitoes are limited to a few far-ranging species and island endemics are typically restricted to the genera of Aedes and Culex. Only lymphatic filariasis appears to have been present as an endemic mosquito-borne disease before European contact. In nearby Australia, however, some 242 species of mosquitoes are known to occur and more than 70 arboviruses have been identified (Mackenzie 1999). In this regard Australia is more similar to the rest of the tropic and subtropical world than the smaller islands of Oceania. In our ever-shrinking world of global commerce, military activity and travel, the nature of mosquito-borne disease in the Pacific was bound to change. This paper is a brief summary of introduced mosquitoes in the Pacific and their potential impacts on human and wildlife health.

  3. Transgenic alteration of Toll immune pathway in the female mosquito Aedes aegypti

    OpenAIRE

    Bian, Guowu; Shin, Sang Woon; Cheon, Hyang-Mi; Kokoza, Vladimir; Raikhel, Alexander S.

    2005-01-01

    Reverse genetics is a powerful tool for understanding gene functions and their interactions in the mosquito innate immunity. We took the transgenic approach, in combination with the RNA interference (RNAi) technique, to elucidate the role of mosquito REL1, a homolog of Drosophila Dorsal, in regulation of Toll immune pathway in the mosquito Aedes aegypti. By transforming the mosquitoes with ΔREL1-A or a double-stranded RNA construct of REL1 driven by the female fat body-specific vitellogenin (...

  4. Transmission of tularemia from a water source by transstadial maintenance in a mosquito vector

    Science.gov (United States)

    Bäckman, Stina; Näslund, Jonas; Forsman, Mats; Thelaus, Johanna

    2015-01-01

    Mosquitoes are thought to function as mechanical vectors of Francisella tularensis subspecies holarctica (F. t. holarctica) causing tularemia in humans. We investigated the clinical relevance of transstadially maintained F. t. holarctica in mosquitoes. Aedes egypti larvae exposed to a fully virulent F. t. holarctica strain for 24 hours, were allowed to develop into adults when they were individually homogenized. Approximately 24% of the homogenates tested positive for F. t. DNA in PCR. Mice injected with the mosquito homogenates acquired tularemia within 5 days. This novel finding demonstrates the possibility of transmission of bacteria by adult mosquitoes having acquired the pathogen from their aquatic larval habitats.

  5. Mosquito-Host Interactions during and after an Outbreak of Equine Viral Encephalitis in Eastern Panama

    Science.gov (United States)

    Navia-Gine, Wayra G.; Loaiza, Jose R.; Miller, Matthew J.

    2013-01-01

    Mosquito blood meals provide information about the feeding habits and host preference of potential arthropod-borne disease vectors. Although mosquito-borne diseases are ubiquitous in the Neotropics, few studies in this region have assessed patterns of mosquito-host interactions, especially during actual disease outbreaks. Based on collections made during and after an outbreak of equine viral encephalitis, we identified the source of 338 blood meals from 10 species of mosquitoes from Aruza Abajo, a location in Darien province in eastern Panama. A PCR based method targeting three distinct mitochondrial targets and subsequent DNA sequencing was used in an effort to delineate vector-host relationships. At Aruza Abajo, large domesticated mammals dominated the assemblage of mosquito blood meals while wild bird and mammal species represented only a small portion of the blood meal pool. Most mosquito species fed on a variety of hosts; foraging index analysis indicates that eight of nine mosquito species utilize hosts at similar proportions while a stochastic model suggests dietary overlap among species was greater than would be expected by chance. The results from our null-model analysis of mosquito diet overlap are consistent with the hypothesis that in landscapes where large domestic animals dominate the local biomass, many mosquito species show little host specificity, and feed upon hosts in proportion to their biomass, which may have implications for the role of livestocking patterns in vector-borne disease ecology. PMID:24339965

  6. The mosquito ultra-low volume dispersion model for estimating environmental concentrations of insecticides used for adult mosquito management.

    Science.gov (United States)

    Schleier, Jerome J; Peterson, Robert K D

    2014-09-01

    Computer models for pesticide drift are widely used tools by regulatory agencies to estimate the deposition of pesticides beyond the intended target area. Currently, there is no model in use that has been validated or verified as an accurate means of estimating concentrations of insecticides after ground-based ultra-low volume (ULV) applications used for adult mosquito management. To address the need for a validated model we created a spreadsheet-based model called Mosquito Ultra-Low Volume Dispersion (MULV-Disp) to aid in the adoption and to provide easier use of a validated model. We explain the origin, use, and utility of MULV-Disp, which can be used by regulatory agencies and other interested parties to estimate deposition of ULV insecticides.

  7. Comparative susceptibility to permethrin of two Anopheles gambiae s.l. populations from Southern Benin, regarding mosquito sex, physiological status, and mosquito age

    Directory of Open Access Journals (Sweden)

    Nazaire Aïzoun

    2014-04-01

    Conclusions: The resistance is a hereditary and dynamic phenomenon which can be due to metabolic mechanisms like overproduction of detoxifying enzymes activity. Many factors influence vector susceptibility to insecticide. Among these factors, there are mosquito sex, mosquito age, its physiological status. Therefore, it is useful to respect the World Health Organization criteria in the assessment of insecticide susceptibility tests in malaria vectors. Otherwise, susceptibility testing is conducted using unfed female mosquitoes aged 3-5 days old. Tests should also be carried out at (25±2 °C and (80±10% relative humidity.

  8. Effectiveness of Print Education at Reducing Urban Mosquito Infestation through Improved Resident-Based Management.

    Directory of Open Access Journals (Sweden)

    Danielle Bodner

    Full Text Available Improving resident-based management and knowledge of mosquitoes is often an integral component of integrated mosquito management, especially in urban landscapes with considerable mosquito habitat on privately owned lands. This study tested the effectiveness of print education materials at reducing urban mosquito exposure through improving resident knowledge of, and attitudes towards, mosquitoes and mosquito management in Washington DC, USA. There was a specific focus on the removal of water-filled containers that are utilized by the developmental stages of the two most common vector species in the region, Aedes albopictus and Culex pipiens. Households in six neighborhoods that varied in socio-economic status were administered knowledge, attitude, and practice (KAP surveys in 2010 and 2012, and had their yards surveyed for container habitats and immature mosquitoes (larvae and pupae in 2010, 2011, and 2012. Half the households (intervention, n = 120 received education materials in 2011 and 2012 to yield a before-after control-intervention (BACI design. Unexpectedly, residents in intervention households were more likely to show decreased concern for mosquito-borne illnesses than residents in control households, which did not receive materials. Moreover, there was a greater probability that control households reduced containers in 2012 than intervention households, particularly when they had low numbers of baseline (2010 containers. Irrespective of control, reductions in containers were associated with decreased abundances of immature mosquitoes. Overall, our findings suggest that print education materials may have unintended negative effects on resident attitudes and household management of mosquito production. We recommend that mosquito control agencies need to carefully consider their content of print messages and the effectiveness of strategies that passively convey information with little or no engagement with control professionals.

  9. Transgenic alteration of Toll immune pathway in the female mosquito Aedes aegypti.

    Science.gov (United States)

    Bian, Guowu; Shin, Sang Woon; Cheon, Hyang-Mi; Kokoza, Vladimir; Raikhel, Alexander S

    2005-09-20

    Reverse genetics is a powerful tool for understanding gene functions and their interactions in the mosquito innate immunity. We took the transgenic approach, in combination with the RNA interference (RNAi) technique, to elucidate the role of mosquito REL1, a homolog of Drosophila Dorsal, in regulation of Toll immune pathway in the mosquito Aedes aegypti. By transforming the mosquitoes with DeltaREL1-A or a double-stranded RNA construct of REL1 driven by the female fat body-specific vitellogenin (Vg) promoter with the pBac[3xP3-EGFP, afm] vector, we generated two different transgenic mosquito strains, one with overexpressed AaREL1 and the second with AaREL1 knockdown. Both strains had a single copy of the respective transgene, and the expression in both transgenic mosquitoes was highly activated by blood feeding. Vg-DeltaREL1-A transgenic mosquitoes activate Toll immune pathway in the fat body by blood feeding. The overexpression of both isoforms, AaREL1-A and AaREL1-B, in Vg-DeltaREL1-A transgenic mosquitoes resulted in the concomitant activation of Aedes Spätzle1A and Serpin-27A, independent of septic injury. The same phenotype was observed in the mosquitoes with RNAi knockdown of an Aedes homolog to Drosophila cactus, an IkappaB inhibitor of Drosophila Toll pathway. The effect of the transgenic RNAi knockdown of AaREL1 on mosquito innate immunity was revealed by increased susceptibility to the entomopathogenic fungus Beauveria bassiana and the reduced induction of Spz1A and Serpin-27A gene expression after fungal challenge. These results have proven that AaREL1 is a key downstream regulator of Toll immune pathway in the mosquito A. aegypti.

  10. Laboratory and field testing of bednet traps for mosquito (Diptera: Culicidae) sampling in West Java, Indonesia.

    Science.gov (United States)

    Stoops, Craig A; Gionar, Yoyo R; Rusmiarto, Saptoro; Susapto, Dwiko; Andris, Heri; Elyazar, Iqbal R F; Barbara, Kathryn A; Munif, Amrul

    2010-06-01

    Surveillance of medically important mosquitoes is critical to determine the risk of mosquito-borne disease transmission. The purpose of this research was to test self-supporting, exposure-free bednet traps to survey mosquitoes. In the laboratory we tested human-baited and unbaited CDC light trap/cot bednet (CDCBN) combinations against three types of traps: the Mbita Trap (MIBITA), a Tent Trap (TENT), and a modified Townes style Malaise trap (TSM). In the laboratory, 16 runs comparing MBITA, TSM, and TENT to the CDCBN were conducted for a total of 48 runs of the experiment using 13,600 mosquitoes. The TENT trap collected significantly more mosquitoes than the CDCBN. The CDCBN collected significantly more than the MBITA and there was no difference between the TSM and the CDCBN. Two field trials were conducted in Cibuntu, Sukabumi, West Java, Indonesia. The first test compared human-baited and unbaited CDCBN, TENT, and TSM traps during six nights over two consecutive weeks per month from January, 2007 to September, 2007 for a total of 54 trapnights. A total of 8,474 mosquitoes representing 33 species were collected using the six trapping methods. The TENT-baited trap collected significantly more mosquitoes than both the CDCBN and the TSM. The second field trial was a comparison of the baited and unbaited TENT and CDCBN traps and Human Landing Collections (HLCs). The trial was carried out from January, 2008 to May, 2008 for a total of 30 trap nights. A total of 11,923 mosquitoes were collected representing 24 species. Human Landing Collections captured significantly more mosquitoes than either the TENT or the CDCBN. The baited and unbaited TENT collected significantly more mosquitoes than the CDCBN. The TENT trap was found to be an effective, light-weight substitute for the CDC light-trap, bednet combination in the field and should be considered for use in surveys of mosquito-borne diseases such as malaria, arboviruses, and filariasis.

  11. Community knowledge and experience of mosquitoes and personal prevention and control practices in Lhasa, Tibet.

    Science.gov (United States)

    Liu, Xiaobo; Wan, Fangjun; Cirendunzhu; Cirenwangla; Bai, Li; Pengcuociren; Zhou, Lin; Baimaciwang; Guo, Yuhong; Dazhen; Xu, Junfang; Sang, Shaowei; Li, Xiaolu; Gu, Shaohua; Wu, Haixia; Wang, Jun; Dawa; Xiraoruodeng; Liu, Qiyong

    2014-09-23

    Since 2009, great public attention has been paid in Lhasa City (Tibet, China) to mosquito bites and accompanying inflammatory complications. However, the potential contribution of knowledge levels, experiences, disease control and preventive practices (KEP) towards mosquitoes has not received much attention. To investigate community KEP concerning mosquitoes in Lhasa, a cross-sectional survey was undertaken in four sub-districts of urban Lhasa in 2012. Questionnaires were designed to collect information regarding socio-demographics and KEP concerning the harmful effects of mosquitoes on participants. The scoring for KEP was developed after consultation of literature. A total of 591 eligible questionnaires were examined. The majority of respondents were female (61.8%) with a mean age of 46 years. Nearly all of the respondents were of Tibetan nationality (97.4%) and living in registered native households (92.7%), who have less than primary school education. The averages of overall score, knowledge score, experience score, and practice score were 9.23, 4.53, 1.80, 2.90, respectively. The registered household with the highest overall score, knowledge score and practice score was non-native. Female subjects with monthly incomes between 1000 and 3000 RMB had higher experience scores. The correlation analysis revealed that significant positive linear correlations existed between knowledge and experience, knowledge and practices, and experience and practices towards mosquitoes. Past experiences with mosquitoes can result in a better knowledge of effective mosquito control practices in the present and the future. Though the average of overall scores related to mosquitoes is high among the participants in Lhasa, however, the knowledge about the ecological habits of mosquitoes should be strengthened. The findings in this study may help to develop strategies and measures of mosquito and mosquito-borne diseases in the future, not only in Lhasa, but also in similar altitude

  12. Fauna anofélica da cidade de Belém, Pará, Brasil: dados atuais e retrospectivos Anophelines in Belém, Pará, Brazil: current and retrospective data

    Directory of Open Access Journals (Sweden)

    Ana de Nazaré Martins da Silva

    2006-08-01

    Full Text Available Relato de coletas de anofelinos realizadas em Belém, Pará, Brasil, de 1995 a 2004, comparando os dados obtidos com os de levantamentos anteriores, feitos a partir da década de 1930. Nesses, vinte espécies haviam sido identificadas: Anopheles albitarsis s.l., An. aquasalis, An. argyritarsis, An. braziliensis, An. darlingi, An. eiseni, An. evansae, An. galvaoi, An. intermedius, An. kompi, An. mediopunctatus, An. nimbus, An. nuneztovari, An. oswaldoi, An. peryassui, An. punctimacula, An. shannoni, An. strodei, An. thomasi e An. triannulatus. Sete (An. argyritarsis, An. eiseni, An. galvaoi, An. kompi, An. nimbus, An. punctimacula e An. thomasi não são agora registradas. A permanência de tantas outras espécies provavelmente decorre da preservação de áreas de mata no âmbito urbano. Duas delas são consideradas de importância vetorial (An. darlingi e An. aquasalis. Esta última continua sendo a de maior densidade nas coletas (46,26% dos adultos e 99,21% das larvas e é a única registrada em todos os distritos administrativos. Existe, portanto, risco potencial de transmissão de malária em todo o município.We present the results of anopheline captures in Belém, Pará, Brazil, from 1995-2004, and a comparison with captures from 1930-1999. In the earlier period, 20 species were identified: Anopheles albitarsis s.l., An. aquasalis, An. argyritarsis, An. braziliensis, An. darlingi, An. eiseni, An. evansae, An. galvaoi, An. intermedius, An. kompi, An. mediopunctatus, An. nimbus, An. nuneztovari, An. oswaldoi, An. peryassui, An. punctimacula, An. shannoni, An. strodei, An. thomasi, and An. triannulatus. Seven of these species were not found in 1995-2004 (An. argyritarsis, An. eiseni, An. galvaoi, An. kompi, An. nimbus, An. punctimacula, and An. thomasi. The persistence of so many species is probably due to the local preservation of forest areas. Two species are of vectorial importance (An. darlingi and An. aquasalis. An. aquasalis is still

  13. Fitness of Transgenic Anopheles stephensi Mosquitoes Expressing the SM1 Peptide under the Control of a Vitellogenin Promoter

    OpenAIRE

    Li, Chaoyang; Marrelli, Mauro T.; Yan, Guiyun; Jacobs-Lorena, Marcelo

    2008-01-01

    Three transgenic Anopheles stephensi lines were established that strongly inhibit transmission of the mouse malaria parasite Plasmodium berghei. Fitness of the transgenic mosquitoes was assessed based on life table analysis and competition experiments between transgenic and wild-type mosquitoes. Life table analysis indicated low fitness load for the 2 single-insertion transgenic mosquito lines VD35 and VD26 and no load for the double-insertion transgenic mosquito line VD9. However, in cage ex...

  14. The biological activity of a-mangostin, a larvicidal botanic mosquito sterol carrier protein-2 inhibitor

    Science.gov (United States)

    Alpha-mangostin derived from mangosteen was identified as a mosquito sterol carrier protein-2 inhibitor via high throughput insecticide screening. Alpha-mangostin was tested for its larvicidal activity against 3rd instar larvae of six mosquito species and the LC50 values range from 0.84 to 2.90 ppm....

  15. Direct and indirect immunosuppression by a malaria parasite in its mosquito vector

    NARCIS (Netherlands)

    Boëte, C.H.J.J.; Paul, R.E.L.; Koëlla, J.C.

    2004-01-01

    Malaria parasites develop as oocysts within the haemocoel of their mosquito vector during a period that is longer than the average lifespan of many of their vectors. How can they escape from the mosquito's immune responses during their long development? Whereas older oocysts might camouflage themsel

  16. Transgenic mosquitoes and the fight against malaria: managing technology push in a turbulent GMO world

    NARCIS (Netherlands)

    Knols, B.G.J.; Bossin, H.C.; Mukabana, W.R.; Robinson, A.S.

    2007-01-01

    Genetic modification (GM) of mosquitoes (which renders them genetically modified organisms, GMOs) offers opportunities for controlling malaria. Transgenic strains of mosquitoes have been developed and evaluation of these to 1) replace or suppress wild vector populations and 2) reduce transmission an

  17. Susceptibility Status of Anopheles sundaicus Mosquitoes Against Insecticides Cypermethrin in Garut Regency

    Directory of Open Access Journals (Sweden)

    Nunung Seniawati

    2010-06-01

    Full Text Available At the time of high vector populations and malaria transmission is in progress, it is necessary to use insecticides to control vector using the house spraying. To get the results as objective the eradication of the vector that is able to suppress the vector population so that no longer play a role in malaria transmission, the insecticide used should be effective against mosquitoes and the mosquitoes are still susceptible to the insecticide used. To determine the level of malaria vector mosquito susceptibility to insecticides, in the terri-tory of Garut district has conducted susceptibility tests of Anopheles sundaicus mosquitoes to insecticides Cypermethrin held in November up to December 2008. Mosquitoes tested were captured in the form of larvae from ponds and estuaries in Karyamukti Cibalong Garut, and then reared in the field insektarium. The adult level were then tested for their susceptibility. Mosquito susceptibility tests conducted using the WHO Susceptibility Test Kit as many as four repetitions performed simultaneously, while the insecticide used in the form of imprag-nated paper with a dose of 0.05%. From tests it is known that mosquito mortality rate up to 100% test. This indicates that the mosquito An. sundaicus in Garut regency of West Java, is still susceptible to the insecticide Cypermenthrin. Therefore, it can still be used in the eradication of malaria vectors in the recommended dosage of 0.20 g/m2.

  18. Mosquito (Diptera: Culicidae Habitat Surveillance by Android Mobile Devices in Guangzhou, China

    Directory of Open Access Journals (Sweden)

    Tai-Ping Wu

    2016-12-01

    Full Text Available In 2014, Guangzhou City, South China, suffered from its worst outbreak of dengue fever in decades. Larval mosquito habitat surveillance was carried out by using android mobile devices in four study sites in May 2015. The habitats with larval mosquitoes were recorded as photo waypoints in OruxMaps or in videos. The total number of potential mosquito habitats was 342, of which 166 (49% were found to have mosquito larvae or pupae. Small containers were the most abundant potential habitats, accounting for 26% of the total number. More mosquito larvae and pupae, were found in small containers than in other objects holding water, for example, potted or hydroponic plants (p < 0.05. Mosquito larvae were collected from all plastic road barriers, used tires, and underground water. Aedes albopictus larvae were found from small and large containers, stumps, among others. The overall route index (RI was 11.3, which was 14.2 times higher than the grade C criteria of the National Patriotic Health Campaign Committee (NPHCC, China. The higher RIs were found from the bird and flower markets, schools, and underground parking lots. The results indicated that Android mobile devices are a convenient and useful tool for surveillance of mosquito habitats, and the enhancement of source reduction may benefit the prevention and control of dengue vector mosquitoes.

  19. Use of geographic information systems to depict and analyze mosquito population trends.

    Science.gov (United States)

    Mosquitoes transmit (vector) disease agents that cause malaria, yellow fever, dengue, West Nile fever, and encephalitis. Spread of these diseases is controlled by the management of mosquito population levels, changes in which are monitored in vector surveillance programs by the use of mechanical tr...

  20. Relative potency of various insecticides for use in ATSBs against mosquitoes and sand flies

    Science.gov (United States)

    Mosquitoes and sand flies are important throughout the world as nuisance pests and vectors of a variety of human and livestock diseases. Control efforts are limited often to adulticide sprays and larvicides, however, environmental concerns restrict their use. Both mosquitoes and sand flies need to...

  1. Innate preference or opportunism: mosquitoes feeding on birds of prey at the Southeastern Raptor Center.

    Science.gov (United States)

    Burkett-Cadena, Nathan D; Bingham, Andrea M; Porterfield, Christopher; Unnasch, Thomas R

    2014-06-01

    The amplification of mosquito-borne pathogens is driven by patterns of host use by vectors. While each mosquito species is innately adapted to feed upon a particular group of hosts, this "preference" is difficult to assess in field-based studies, because factors such as host defenses and spatial and temporal overlap of mosquitoes and hosts affect which host animals actually get bitten. Here we examined patterns of host use by mosquitoes feeding on caged raptors at a rehabilitation and education center for birds of prey in Alabama, U.S.A. PCR-based techniques were used to determine the host species fed upon. Of 19 raptor species at the facility, seven were found to be fed upon by mosquitoes. Feeding indices and linear regression indicated that no species or family of raptor were significantly preferred over another (R(2)=0.46). Relative abundance adjusted for bird size explained a statistically significant amount of the variation in relative host use (R(2)=0.71), suggesting that bird size is an important component of host selection by mosquitoes. These findings support the hypothesis that traits of host animals drive patterns of host use by mosquitoes in nature, an interaction that leads to amplification of mosquito-borne viruses.

  2. Vertical Transmission of Zika Virus by Aedes aegypti and Ae. albopictus Mosquitoes.

    Science.gov (United States)

    Ciota, Alexander T; Bialosuknia, Sean M; Ehrbar, Dylan J; Kramer, Laura D

    2017-05-15

    To determine the potential role of vertical transmission in Zika virus expansion, we evaluated larval pools of perorally infected Aedes. aegypti and Ae. albopictus adult female mosquitoes; ≈1/84 larvae tested were Zika virus-positive; and rates varied among mosquito populations. Thus, vertical transmission may play a role in Zika virus spread and maintenance.

  3. Infection of adult Aedes aegypti and Ae. albopictus mosquitoes with the entomopathogenic fungus Metarhizium anisopliae

    NARCIS (Netherlands)

    Scholte, E.J.; Takken, W.; Knols, B.G.J.

    2007-01-01

    This study describes a laboratory investigation on the use of the insect-pathogenic fungus Metarhizium anisopliae against adult Aedes aegypti and Ae. albopictus mosquitoes. At a dosage of 1.6 × 1010 conidia/m2, applied on material that served as a mosquito resting site, an average of 87.1 ± 2.65% of

  4. Mosquito and Drosophila entomobirnaviruses suppress dsRNA- and siRNA-induced RNAi

    NARCIS (Netherlands)

    Cleef, K.W. van; Mierlo, J.T. van; Miesen, P.; Overheul, G.J.; Fros, J.J.; Schuster, S.; Marklewitz, M.; Pijlman, G.P.; Junglen, S.; Rij, R.P. van

    2014-01-01

    RNA interference (RNAi) is a crucial antiviral defense mechanism in insects, including the major mosquito species that transmit important human viruses. To counteract the potent antiviral RNAi pathway, insect viruses encode RNAi suppressors. However, whether mosquito-specific viruses suppress RNAi r

  5. The presence of Plasmodium falciparum gametocytes in human blood increases the gravidity of Anopheles gambiae mosquitoes

    NARCIS (Netherlands)

    Ferguson, H.M.; Gouagna, L.C.; Obare, P.; Read, A.F.; Babiker, H.; Githure, J.I.; Beier, J.C.

    2005-01-01

    We conducted a field study in an area of endemic malaria transmission in western Kenya to determine whether mosquitoes that feed on gametocyte-infected blood but do not become infected have reduced or enhanced fecundity in comparison to mosquitoes fed on uninfected blood. Fifteen paired membrane-fee

  6. Mosquito biodiversity patterns around urban environments in South-central okinawa island, Japan.

    Science.gov (United States)

    Hoshi, Tomonori; Imanishi, Nozomi; Higa, Yukiko; Chaves, Luis Fernando

    2014-12-01

    Okinawa is the largest, most urbanized, and densely populated island in the Ryukyus Archipelago, where mosquito species diversity has been thoroughly studied. However, the south-central Okinawa mosquito fauna has been relatively poorly studied. Here, we present results from a mosquito faunal survey in urban environments of Nishihara city, south-central Okinawa. Mosquitoes were sampled biweekly, from April 2007 to March 2008, at 3 different environments: a forest preserve, an animal farm, and a water reservoir. We employed 4 mosquito collection methods: 1) oviposition traps; 2) light traps; 3) sweep nets; and 4) larval surveys of tree holes, leaf axils, and artificial water containers. We collected a total of 568 adults and 10,270 larvae belonging to 6 genera and 13 species, including 6 species of medical importance: Aedes albopictus, Armigeres subalbatus, Anopheles Hyrcanus group, Culex bitaeniorhynchus, Cx. quinquefasciatus, and Cx. tritaeniorhynchus. Mosquito species composition was similar to data from previous studies in Okinawa Island. The flattening of the species accumulation curve suggests that our diversity sampling was exhaustive with light and oviposition traps, as well as the coincidence between the species richness we found in the field and estimates from the Chao2 index, a theoretical estimator of species richness based on species abundance. This study highlights the importance of combining several sampling techniques to properly characterize regional mosquito fauna and to monitor changes in the presence of mosquito species.

  7. Response of adult mosquitoes to light emitting diodes placed in resting boxes and in the field.

    Science.gov (United States)

    Resting boxes are passive devices used to attract and capture mosquitoes seeking shelter. Increasing the attractiveness of these devices could improve their effectiveness. Light emitting diodes (LEDs) can be attractive to mosquitoes when used together with other trapping devices. Therefore restin...

  8. Limited dengue virus replication in field-collected Aedes aegypti mosquitoes infected with Wolbachia.

    Directory of Open Access Journals (Sweden)

    Francesca D Frentiu

    2014-02-01

    Full Text Available INTRODUCTION: Dengue is one of the most widespread mosquito-borne diseases in the world. The causative agent, dengue virus (DENV, is primarily transmitted by the mosquito Aedes aegypti, a species that has proved difficult to control using conventional methods. The discovery that A. aegypti transinfected with the wMel strain of Wolbachia showed limited DENV replication led to trial field releases of these mosquitoes in Cairns, Australia as a biocontrol strategy for the virus. METHODOLOGY/PRINCIPAL FINDINGS: Field collected wMel mosquitoes that were challenged with three DENV serotypes displayed limited rates of body infection, viral replication and dissemination to the head compared to uninfected controls. Rates of dengue infection, replication and dissemination in field wMel mosquitoes were similar to those observed in the original transinfected wMel line that had been maintained in the laboratory. We found that wMel was distributed in similar body tissues in field mosquitoes as in laboratory ones, but, at seven days following blood-feeding, wMel densities increased to a greater extent in field mosquitoes. CONCLUSIONS/SIGNIFICANCE: Our results indicate that virus-blocking is likely to persist in Wolbachia-infected mosquitoes after their release and establishment in wild populations, suggesting that Wolbachia biocontrol may be a successful strategy for reducing dengue transmission in the field.

  9. A stage structured mosquito model incorporating effects of precipitation and daily temperature fluctuations.

    Science.gov (United States)

    Wang, Xia; Tang, Sanyi; Cheke, Robert A

    2016-12-21

    An outbreak of dengue fever in Guangdong province in 2014 was the most serious outbreak ever recorded in China. Given the known positive correlation between the abundance of mosquitoes and the number of dengue fever cases, a stage structured mosquito model was developed to investigate the cause of the large abundance of mosquitoes in 2014 and its implications for outbreaks of the disease. Data on the Breteau index (number of containers positive for larvae per 100 premises investigated), temperature and precipitation were used for model fitting. The egg laying rate, the development rate and the mortality rates of immatures and adults were obtained from the estimated parameters. Moreover, effects of daily fluctuations of temperature on these parameters were obtained and the effects of temperature and precipitation were analyzed by simulations. Our results indicated that the abundance of mosquitoes depended not only on the total annual precipitation but also on the distribution of the precipitation. The daily mean temperature had a nonlinear relationship with the abundance of mosquitoes, and large diurnal temperature differences can reduce the abundance of mosquitoes. In addition, effects of increasing precipitation and temperature were interdependent. Our findings suggest that the large abundance of mosquitoes in 2014 was mainly caused by the distribution of the precipitation. In the perspective of mosquito control, our results reveal that it is better to clear water early and spray insecticide between April and August in case of limited resources.

  10. 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...... in rice fields, thereby making them visually more attractive for egg-laying by An. arabiensis and culicine mosquitoes....

  11. Modulation of La Crosse virus infection in Aedes albopictus mosquitoes following larval exposure to coffee extracts

    Directory of Open Access Journals (Sweden)

    Nicole E. Eastep

    2012-03-01

    Full Text Available The mosquito-borne La Crosse virus (LACV; Family Bunyaviridae may cause encephalitis, primarily in children, and is distributed throughout much of the eastern United States. No antivirals or vaccines are available for LACV, or most other mosquito-borne viruses, and prevention generally relies on mosquito control. We sought to determine whether coffee extracts could interfere with LACV replication and vector mosquito development. Both regular and decaffeinated coffee demonstrated significant reductions in LACV replication in direct antiviral assays. This activity was not due to the presence of caffeine, which did not inhibit the virus life cycle. Aedes albopictus (Skuse (Diptera: Culicidae mosquito larvae suffered near total mortality when reared in high concentrations of regular and decaffeinated coffee and in caffeine. Following larval exposure to sublethal coffee concentrations, adult Ae. albopictus mosquitoes had signficantly reduced whole-body LACV titers five days post-infection, compared to larvae reared in distilled water. These results suggest that it may be possible to both control mosquito populations and alter the vector competence of mosquitoes for arthropod-borne viruses by introducing antiviral compounds into the larval habitat.

  12. Implication of the mosquito midgut microbiota in the defense against malaria parasites.

    Directory of Open Access Journals (Sweden)

    Yuemei Dong

    2009-05-01

    Full Text Available Malaria-transmitting mosquitoes are continuously exposed to microbes, including their midgut microbiota. This naturally acquired microbial flora can modulate the mosquito's vectorial capacity by inhibiting the development of Plasmodium and other human pathogens through an unknown mechanism. We have undertaken a comprehensive functional genomic approach to elucidate the molecular interplay between the bacterial co-infection and the development of the human malaria parasite Plasmodium falciparum in its natural vector Anopheles gambiae. Global transcription profiling of septic and aseptic mosquitoes identified a significant subset of immune genes that were mostly up-regulated by the mosquito's microbial flora, including several anti-Plasmodium factors. Microbe-free aseptic mosquitoes displayed an increased susceptibility to Plasmodium infection while co-feeding mosquitoes with bacteria and P. falciparum gametocytes resulted in lower than normal infection levels. Infection analyses suggest the bacteria-mediated anti-Plasmodium effect is mediated by the mosquitoes' antimicrobial immune responses, plausibly through activation of basal immunity. We show that the microbiota can modulate the anti-Plasmodium effects of some immune genes. In sum, the microbiota plays an essential role in modulating the mosquito's capacity to sustain Plasmodium infection.

  13. PERCEPTIONS REGARDING MOSQUITO BORNE DISEASES IN AN URBAN AREA OF RAJKOT CITY

    Directory of Open Access Journals (Sweden)

    Amul B. Patel

    2011-04-01

    Full Text Available Background: Mosquito borne diseases is a growing urban problem because of unplanned urbanization, industrialization and excessive population growth coupled with rural to urban migration. For developing a suitable and effective health education strategy, it is inevitable to understand the level of knowledge of the community, their attitude and practices regarding mosquito borne diseases. Materials and Methods: The present study was carried out in an urban field practice area of Urban Health Centre in Rajkot city. Total 500 houses were selected for study by systematic random sampling. Data was collected using a semi-structured questionnaire during transmission season of vector borne diseases. The results were analyzed using the SPSS 17 software. Results: 90% respondents agreed that mosquitoes are a problem. 30.4% didn’t know breeding sites of mosquitoes. Only 11.6% of people associated clean water collections with mosquito breeding. Regarding diseases transmitted by mosquito, 62% answered malaria, 37.4% were not aware and 8.8% people mentioned about Filariasis, Dengue or Japanese encephalitis. 4.7% granted mosquito control as responsibility of community. 61.4 % were using repellents for prevention against mosquito bites and 39% not taking any preventive measure. 67.8% consulted private practitioner for treatment. Conclusion: Intensified efforts towards creating public awareness and mobilizing the community regarding the preventive measures they can take are needed. [National J of Med Res 2011; 1(2.000: 45-47

  14. Using a near-infrared spectrometer to estimate the age of Anopheles mosquitoes exposed to pyrethroids

    Science.gov (United States)

    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 ol...

  15. Blood Meal Analysis of Mosquitoes Involved in a Rift Valley fever Outbreak

    Science.gov (United States)

    Background: Rift Valley fever (RVF) is a zoonosis of domestic ruminants in Africa. Bloodfed mosquitoes collected during the 2006-2007 RVF outbreak in Kenya were analyzed to determine the virus infection status and animal source of the bloodmeals. Bloodmeals from individual mosquito abdomens were sc...

  16. Annual Anastasia Arbovirus Surveillance and Mosquito Control Workshops: Summary of the Past 11 Years

    Science.gov (United States)

    Realizing the needs of local mosquito control workers for advance training and education the Anastasia Mosquito Control District (AMCD) and the USDA-ARS Center for Medical, Agricultural and Veterinary entomology (CMAVE) developed a regional workshop to address these needs. Since 2004 the AMCD and CM...

  17. Rapid selection against arbovirus-induced apoptosis during infection of a mosquito vector.

    Science.gov (United States)

    O'Neill, Katelyn; Olson, Bradley J S C; Huang, Ning; Unis, Dave; Clem, Rollie J

    2015-03-10

    Millions of people are infected each year by arboviruses (arthropod-borne viruses) such as chikungunya, dengue, and West Nile viruses, yet for reasons that are largely unknown, only a relatively small number of mosquito species are able to transmit arboviruses. Understanding the complex factors that determine vector competence could facilitate strategies for controlling arbovirus infections. Apoptosis is a potential antiviral defense response that has been shown to be important in other virus-host systems. However, apoptosis is rarely seen in arbovirus-infected mosquito cells, raising questions about its importance as an antiviral defense in mosquitoes. We tested the effect of stimulating apoptosis during arbovirus infection by infecting Aedes aegypti mosquitoes with a Sindbis virus (SINV) clone called MRE/Rpr, in which the MRE-16 strain of SINV was engineered to express the proapoptotic gene reaper from Drosophila. MRE/Rpr exhibited an impaired infection phenotype that included delayed midgut infection, delayed virus replication, and reduced virus accumulation in saliva. Nucleotide sequencing of the reaper insert in virus populations isolated from individual mosquitoes revealed evidence of rapid and strong selection against maintenance of Reaper expression in MRE/Rpr-infected mosquitoes. The impaired phenotype of MRE/Rpr, coupled with the observed negative selection against Reaper expression, indicates that apoptosis is a powerful defense against arbovirus infection in mosquitoes and suggests that arboviruses have evolved mechanisms to avoid stimulating apoptosis in mosquitoes that serve as vectors.

  18. Don't Let the Bugs Bite: Preventing Dengue and Other Diseases Spread by Mosquitoes

    Centers for Disease Control (CDC) Podcasts

    2007-12-10

    This year (2007) CDC is receiving a great many reports of cases of Dengue fever, which is spread by mosquitoes. This podcast discusses ways travelers to the tropics can protect themselves from mosquito bites.  Created: 12/10/2007 by National Center for the Prevention, Detection and Control of Infectious Diseases (NCPDCID).   Date Released: 12/10/2007.

  19. Orientation of Culex mosquitoes to carbon dioxide-baited traps: flight manoeuvres and trapping efficiency.

    Science.gov (United States)

    Cooperband, M F; Cardé, R T

    2006-03-01

    Females of Culex quinquefasciatus Say and Culex tarsalis Coquillet (Diptera: Culicidae) in the host-seeking stage were released and video recorded in three dimensions in a large field wind tunnel as they flew to four kinds of CO2-baited mosquito traps. The trapping efficiency (number of mosquitoes approaching compared to the number caught) was determined for each trap type. The Encephalitis Virus Surveillance (EVS), Mosquito Magnet Freedom (MMF) and Mosquito Magnet Liberty (MML) traps captured only 13-16% of approaching Cx. quinquefasciatus females, whereas the Mosquito Magnet-X (MMX) trap captured 58%. Similar results were obtained for Cx. tarsalis. Orientation behaviour and flight parameters of mosquitoes approaching the four traps were compared. Mosquitoes spent the most time orienting to the EVS trap. Flight speed decreased as mosquitoes entered the vicinity of each trap and a large portion of their time was spent within 30 cm downwind of the traps. Flights became highly tortuous downwind of the poorly performing traps and just upwind of the MMX trap. Differences between traps and possible explanations for the superior performance of the MMX trap are considered.

  20. Gustatory receptor neuron responds to chemically diverse insect repellents in the common malaria mosquito Anopheles quadrimaculatus

    Science.gov (United States)

    Female mosquitoes feed on blood from animal hosts to obtain nutritional resources used for egg production. These contacts facilitate the spread of harmful human diseases. Chemical repellents are used to disrupt mosquito host seeking and blood feeding behaviors; however, little is known about the g...

  1. Comparison of carbohydrate sources in yeast-fermentation CO2 generators for mosquito surveillance

    Science.gov (United States)

    Mosquito surveillance in remote areas with limited access to canisters of CO2 or dry ice will benefit from an effective alternative CO2 source, such as the natural production of CO2 from yeast fermentation of several carbohydrate sources. In this study, we document the differences in mosquito and n...

  2. British container breeding mosquitoes: the impact of urbanisation and climate change on community composition and phenology.

    Directory of Open Access Journals (Sweden)

    Susannah Townroe

    Full Text Available The proliferation of artificial container habitats in urban areas has benefitted urban adaptable mosquito species globally. In areas where mosquitoes transmit viruses and parasites, it can promote vector population productivity and fuel mosquito-borne disease outbreaks. In Britain, storage of water in garden water butts is increasing, potentially expanding mosquito larval habitats and influencing population dynamics and mosquito-human contact. Here we show that the community composition, abundance and phenology of mosquitoes breeding in experimental water butt containers were influenced by urbanisation. Mosquitoes in urban containers were less species-rich but present in significantly higher densities (100.4±21.3 per container than those in rural containers (77.7±15.1. Urban containers were dominated by Culex pipiens (a potential vector of West Nile Virus [WNV] and appear to be increasingly exploited by Anopheles plumbeus (a human-biting potential WNV and malaria vector. Culex phenology was influenced by urban land use type, with peaks in larval abundances occurring earlier in urban than rural containers. Among other factors, this was associated with an urban heat island effect which raised urban air and water temperatures by 0.9°C and 1.2°C respectively. Further increases in domestic water storage, particularly in urban areas, in combination with climate changes will likely alter mosquito population dynamics in the UK.

  3. Vector competence of Aedes aegypti mosquitoes for filarial nematodes is affected by age and nutrient limitation.

    Science.gov (United States)

    Ariani, Cristina V; Juneja, Punita; Smith, Sophia; Tinsley, Matthew C; Jiggins, Francis M

    2015-01-01

    Mosquitoes are one of the most important vectors of human disease. The ability of mosquitoes to transmit disease is dependent on the age structure of the population, as mosquitoes must survive long enough for the parasites to complete their development and infect another human. Age could have additional effects due to mortality rates and vector competence changing as mosquitoes senesce, but these are comparatively poorly understood. We have investigated these factors using the mosquito Aedes aegypti and the filarial nematode Brugia malayi. Rather than observing any effects of immune senescence, we found that older mosquitoes were more resistant, but this only occurred if they had previously been maintained on a nutrient-poor diet of fructose. Constant blood feeding reversed this decline in vector competence, meaning that the number of parasites remained relatively unchanged as mosquitoes aged. Old females that had been maintained on fructose also experienced a sharp spike in mortality after an infected blood meal ("refeeding syndrome") and few survived long enough for the parasite to develop. Again, this effect was prevented by frequent blood meals. Our results indicate that old mosquitoes may be inefficient vectors due to low vector competence and high mortality, but that frequent blood meals can prevent these effects of age.

  4. Development and Field Evaluation of a Synthetic Mosquito Lure That Is More Attractive than Humans

    NARCIS (Netherlands)

    Okumu, F.O.; Killeen, G.F.; Ogoma, S.; Biswaro, L.; Smallegange, R.C.; Mbeyela, E.; Titus, E.; Munk, C.; Ngonyani, H.; Takken, W.; Mshinda, H.; Mukabana, W.R.; Moore, S.J.

    2010-01-01

    Background - Disease transmitting mosquitoes locate humans and other blood hosts by identifying their characteristic odor profiles. Using their olfactory organs, the mosquitoes detect compounds present in human breath, sweat and skins, and use these as cues to locate and obtain blood from the humans

  5. Studies of Infection and Dissemination of Rift Valley Fever Virus in Mosquitoes.

    Science.gov (United States)

    1991-10-15

    mosquitoes and to determine the dissemination status of orally fed mosquitoes based on the presence of infectious particles in dissected legs. A brief...875-4631 FAX (703) 875-5490 Dr. Adolfo Martinez-Palomo Depto. de Patologia Experimental CENTRO DE INVESTIGACION Y DE ESTUDIOS AVANZADOS DEL I.P.N

  6. A push-pull system to reduce house entry of malaria mosquitoes

    NARCIS (Netherlands)

    Menger, D.J.; Otieno, B.; Rijk, de M.; Mukabana, W.R.; Loon, van J.J.A.; Takken, W.

    2014-01-01

    Background. Mosquitoes are the dominant vectors of pathogens that cause infectious diseases such as malaria, dengue, yellow fever and filariasis. Current vector control strategies often rely on the use of pyrethroids against which mosquitoes are increasingly developing resistance. Here, a push-pull

  7. Importance of waste stabilization ponds and wastewater irrigation in the generation of vector mosquitoes in Pakistan

    DEFF Research Database (Denmark)

    Mukhtar, Muhammad; Ensink, Jeroen; Van der Hoek, Wim;

    2006-01-01

    The objective of the current study was to investigate the role of waste stabilization ponds (WSP) and wastewater-irrigated sites for the production of mosquitoes of medical importance. Mosquito larvae were collected fortnightly from July 2001 to June 2002 in Faisalabad, Pakistan. In total, 3...

  8. 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

  9. A novel in vitro bioassay to explore the repellent effects of compounds against mosquito Aedes Aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Mosquitoes are vectors for many pathogens that can cause human diseases which can result in high rates of human morbidity and mortality at significant levels of transmission. Repellents play an important role in reducing mosquito bites and hence the risk of spread of mosquito borne diseases. Current...

  10. Swarming mechanisms in the yellow fever mosquito: aggregation pheromones involved in the mating behavior of Aedes aegypti

    Science.gov (United States)

    Mosquitoes of various species mate in swarms comprised of tens to thousands flying males. Yet little information is known about mosquito swarming mechanism. Discovering chemical cues involved in mosquito biology leads to better adaptation of disease control interventions. In this study, we aimed ...

  11. Assessing the efficacy of candidate mosquito repellents against the background of an attractive source that mimics a human host

    NARCIS (Netherlands)

    Menger, D.J.; Loon, van J.J.A.; Takken, W.

    2014-01-01

    Mosquito repellents are used around the globe to protect against nuisance biting and disease-transmitting mosquitoes. Recently, there has been renewed interest in the development of repellents as tools to control the transmission of mosquito-borne diseases. We present a new bioassay for the accurate

  12. First report of the infection of insecticide-resistant malaria vector mosquitoes with an entomopathogenic fungus under field conditions

    NARCIS (Netherlands)

    Howard, A.F.V.; N'Guessan, R.; Koenraadt, C.J.M.; Asidi, A.; Farenhorst, M.; Akogbeto, M.; Knols, B.G.J.; Takken, W.

    2011-01-01

    Background - Insecticide-resistant mosquitoes are compromising the ability of current mosquito control tools to control malaria vectors. A proposed new approach for mosquito control is to use entomopathogenic fungi. These fungi have been shown to be lethal to both insecticide-susceptible and insecti

  13. Seasonal abundance and potential of Japanese encephalitis virus infection in mosquitoes at the nesting colony of ardeid birds, Thailand

    Institute of Scientific and Technical Information of China (English)

    Tanasak Changbunjong; Thekhawet Weluwanarak; Namaoy Taowan; Parut Suksai; Tatiyanuch Chamsai; Poonyapat Sedwisai

    2013-01-01

    Objective:To investigate the abundance and seasonal dynamics of mosquitoes, and to detect Japanese encephalitis virus (JEV) in these mosquitoes at the nesting colony of ardeid birds. Methods: Mosquitoes were collected bimonthly from July 2009 to May 2010 by Centers for Disease Control. Light traps and dry ice, as a source of CO2, were employed to attract mosquitoes. Mosquitoes were first identified, pooled into groups of upto 50 mosquitoes by species, and tested for JEV infection by viral isolation and reverse transcriptase polymerase chain reaction. Results:A total of 20 370 mosquitoes comprising 14 species in five genera were collected. The five most abundant mosquito species collected were Culex tritaeniorhynchus (95.46%), Culex vishnui (2.68%), Culex gelidus (0.72%), Anopheles peditaeniatus (0.58%) and Culex quinquefasciatus (0.22%). Mosquito peak densities were observed in July. All of 416 mosquito pools were negative for JEV. Conclusions: This study provides new information about mosquito species and status of JEV infection in mosquitoes in Thailand. Further study should be done to continue a close survey for the presence of this virus in the ardeid birds.

  14. The suitability of clay pots for indoor sampling of mosquitoes in an arid area in northern Tanzania

    NARCIS (Netherlands)

    Bijllaardt, van den W.; Braak, ter R.; Shekalaghe, S.; Otieno, S.; Mahande, A.; Sauerwein, R.; Takken, W.; Bousema, T.

    2009-01-01

    Water storage clay pots have been recently explored as method for outdoor mosquito sampling and as novel device for administrating insect-pathogenic fungi to mosquitoes. Their suitability for indoor mosquito sampling in natural conditions is unknown. We tested clay pots as indoor resting sites along

  15. Comparison of volatiles and mosquito capture efficacy for three carbohydrate sources in a yeast-fermentation CO2 generator

    Science.gov (United States)

    Mosquito surveillance in remote areas with limited access to canisters of CO2 or dry ice will benefit from an effective alternative CO2 source. In this study, we document the differences in mosquito and non-mosquito capture rates from CO2 baited (dry ice or yeast fermentation of carbohydrates) CDC t...

  16. Comparison of mosquito control programs in seven urban sites in Africa, the Middle East, and the Americas

    Science.gov (United States)

    Impoinvil, Daniel E.; Ahmad, Sajjad; Troyo, Adriana; Keating, Joseph; Githeko, Andrew K.; Mbogo, Charles M; Kibe, Lydiah; Githure, John I.; Gad, Adel M.; Hassan, Ali N.; Orshan, Laor; Warburg, Alon; Calderón-Arguedas, Olger; Sánchez-Loría, Victoria M.; Velit-Suarez, Rosanna; Chadee, Dave D.; Novak, Robert J.; Beier, John C.

    2007-01-01

    Mosquito control programs at seven urban sites in Kenya, Egypt, Israel, Costa Rica, and Trinidad are described and compared. Site-specific urban and disease characteristics, organizational diagrams, and strengths, weaknesses, obstacles and threats (SWOT) analysis tools are used to provide a descriptive assessment of each mosquito control program, and provide a comparison of the factors affecting mosquito abatement. The information for SWOT analysis is collected from surveys, focus group discussions, and personal communication. SWOT analysis identified various issues affecting the efficiency and sustainability of mosquito control operations. The main outcome of our work was the description and comparison of mosquito control operations within the context of each study site’s biological, social, political, management, and economic conditions. The issues identified in this study ranged from lack of inter-sector collaboration to operational issues of mosquito control efforts. A lack of sustainable funding for mosquito control was a common problem for most sites. Many unique problems were also identified, which included lack of mosquito surveillance, lack of law enforcement, and negative consequences of human behavior. Identifying common virtues and shortcomings of mosquito control operations is useful in identifying “best practices” for mosquito control operations, thus leading to better control of mosquito biting and mosquito-borne disease transmission. PMID:17316882

  17. First report of behavioural lateralisation in mosquitoes: right-biased kicking behaviour against males in females of the Asian tiger mosquito, Aedes albopictus.

    Science.gov (United States)

    Benelli, Giovanni; Romano, Donato; Messing, Russell H; Canale, Angelo

    2015-04-01

    Lateralisation (i.e. functional and/or structural specialisations of left and right sides of the brain) of aggressive traits has been studied in a number of vertebrates, while evidence for invertebrates is scarce. Mosquito females display aggressive responses against undesired males, performing rejection kicks with the hind legs. In this research, we examined lateralisation of kicking behaviour in females of the Asian tiger mosquito, Aedes albopictus. We found a right-biased population-level lateralisation of kicking behaviour. Four repeated testing phases on mosquito females confirmed the preferential use of right legs. However, when left legs were used, the mean number of kicks per rejection event was not different to that performed with right legs. Both left and right kicking behaviour lead to successful displacement of undesired partners. This is the first report about behavioural lateralisation in mosquitoes.

  18. Lista dos mosquitos da Bolívia: (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    N. L. Cerqueira

    1943-08-01

    Full Text Available Em quinze gêneros, cento e vinte e seis espécies de mosquitos foram constatadas no material capturado pelo Servicio de Fiebre Amarilla desde 1933 até 1942. Êste número, três vezes mais elevado do que o existente na literatura para o país, seria ainda maior se possível fôsse identificar sem o auxílio de machos inúmeras fêmeas das espécies de Culex. Tôdas as espécies estudadas apresentavam suas distribuições geográficas nos departamentos e províncias onde casos de Febre Amarela foram observados. Algumas cosiderações foram feitas em torno de espécies que não correspondiam exatamente com as descrições existentes, assim como descrições de outras foram dadas, cujos sexos opostos apenas eram conhecidos.One hundred and twenty-six species of mosquitoes, corresponding fifteen genera, have been found in material collected by the Bolivian Yellow Fever Service between 1933 and 1942. This number is three times that given for the country in existing literature and would be even largar if it were possible to identify a consierable group of Culex mosquitoes composed principally of female specimens. All species studied come from Departmetns and Provinces where cases of yellow fever have been found. Consideration has been given to certain species which do not agree exactly with existing descriptions, and supplementary descriptions have been made for the male or female of two additional species for which only description of the opposite sex had existed.

  19. LARVICIDAL POTENTIAL AND MOSQUITO REPELLENT ACTIVITY OF CASSIA MIMOSOIDES EXTRACTS.

    Science.gov (United States)

    Alayo, M A; Femi-Oyewo, M N; Bakre, L G; Fashina, A O

    2015-07-01

    This study aims to investigate larvicidal activities of extracts of Cassia mimosoides leaves and pods as a potential agent in vector control of malaria and to evaluate repellent effect against Anopheles gambiae mosquito of the extract formulated in an aqueous cream base. Petroleum spirit, ethanol, water and dichloromethane extracts were tested against third and fourth instar Anopheles gambiae larvae. The petroleum extract was formulated in an aqueous cream base and repellency determined using N-N-diethyl-m-toluamide (DEET) as control. Phytochemical analysis showed the presence of saponins, tannins, anthraquinones, steroids, and flavonoids but absence of cardiac glycosides and alkaloids in powdered C. mimosoides. A dose related response was observed in the mortality rate of the extracts, with 2 mg/ml petroleum ether and dichloromethane extracts achieving 100 % mortality. Larvicidal activity of extracts based on LC50 values was petroleum ether > dichloromethane > ethanol > water. The formulated petroleum ether extract cream had a characteristic odor, hard and smooth texture, skin feeling of smoothness, ease of application by rubbing, easy removal using soap and water, non-irritating effect on skin and an acceptable pH value. The cream containing 2%-6% (w/w) extract and control achieved 100% repellency against mosquitoes after an exposure time of 5 minutes. There was a linear relationship between percent concentration of plant extract in the cream samples and repellent activity. These results suggest that crude extracts of C. mimosoides can be developed as eco-friendly larvicide and mosquito repellent and encourage further effort to investigate the bioactive compounds in the extracts.

  20. Climate-based models for West Nile Culex mosquito vectors in the Northeastern US

    Science.gov (United States)

    Gong, Hongfei; Degaetano, Arthur T.; Harrington, Laura C.

    2011-05-01

    Climate-based models simulating Culex mosquito population abundance in the Northeastern US were developed. Two West Nile vector species, Culex pipiens and Culex restuans, were included in model simulations. The model was optimized by a parameter-space search within biological bounds. Mosquito population dynamics were driven by major environmental factors including temperature, rainfall, evaporation rate and photoperiod. The results show a strong correlation between the timing of early population increases (as early warning of West Nile virus risk) and decreases in late summer. Simulated abundance was highly correlated with actual mosquito capture in New Jersey light traps and validated with field data. This climate-based model simulates the population dynamics of both the adult and immature mosquito life stage of Culex arbovirus vectors in the Northeastern US. It is expected to have direct and practical application for mosquito control and West Nile prevention programs.

  1. Phenoloxidase activity acts as a mosquito innate immune response against infection with Semliki Forest virus.

    Directory of Open Access Journals (Sweden)

    Julio Rodriguez-Andres

    Full Text Available Several components of the mosquito immune system including the RNA interference (RNAi, JAK/STAT, Toll and IMD pathways have previously been implicated in controlling arbovirus infections. In contrast, the role of the phenoloxidase (PO cascade in mosquito antiviral immunity is unknown. Here we show that conditioned medium from the Aedes albopictus-derived U4.4 cell line contains a functional PO cascade, which is activated by the bacterium Escherichia coli and the arbovirus Semliki Forest virus (SFV (Togaviridae; Alphavirus. Production of recombinant SFV expressing the PO cascade inhibitor Egf1.0 blocked PO activity in U4.4 cell- conditioned medium, which resulted in enhanced spread of SFV. Infection of adult female Aedes aegypti by feeding mosquitoes a bloodmeal containing Egf1.0-expressing SFV increased virus replication and mosquito mortality. Collectively, these results suggest the PO cascade of mosquitoes plays an important role in immune defence against arboviruses.

  2. Diversity and distribution of tree hole mosquitoes in Puducherry Union Territory, India

    Institute of Scientific and Technical Information of China (English)

    Periyasamy Senthamarai Selvan; Arulsamy Jebanesan; Chinnusamy Makesh Kumar

    2015-01-01

    Objective:To study diversity and distribution of tree hole mosquitoes at Puducherry Union Territory. Methods:Random collections were carried out in tree holes at collection sites by using suction tube. Mosquitoes are identified by standard entomological procedures. Results: A total of 235 mosquitoes were collected from tree holes, comprising 3 genera and 12 species. They are,Aedes aegypti, Aedes albopictus, Aedes stokesi, Aedes simpsoni, Anopheles subpictus, Anopheles stephensi, Anopheles culiciformis, Anopheles maculatus, Culex quinquefasciatus, Culex pseudovishnui, Culex tritaeniorhynchus, and Culex decens. The results reveal thatAedes species is the dominant species in tree holes. Simpson’s dominance index and Shanon-Wiener diversity index of 0.182 7 and 0.833 6 were respectively recorded for all tree hole mosquitoes. Conclusions:The diversity studies of tree hole mosquitoes in the study area are necessary for the implementation of appropriate control strategies.

  3. Transfer of toxin genes to alternate bacterial hosts for mosquito control

    Directory of Open Access Journals (Sweden)

    Sergio Orduz

    1995-02-01

    Full Text Available Mosquitoes are vector of serious human and animal diseases, such as malaria, dengue, yellow fever, among others. The use of biological control agents has provide an environmentally safe and highly specific alternative to the use of chemical insecticides in the control of vector borne diseases. Bacillus thuringiensis and B. sphaericus produce toxic proteins to mosquito larvae. Great progress has been made on the biochemical and molecular characterization of such proteins and the genes encoding them. Nevertheless, the low residuality of these biological insecticides is one of the major drawbacks. This article present some interesting aspects of the mosquito larvae feeding habits and review the attempts that have been made to genetically engineer microorganisms that while are used by mosquito larvae as a food source should express the Bacillus toxin genes in order to improve the residuality and stability in the mosquito breeding ponds.

  4. Multiple mutations and mutation combinations in the sodium channel of permethrin resistant mosquitoes, Culex quinquefasciatus

    Science.gov (United States)

    Li, Ting; Zhang, Lee; Reid, William R.; Xu, Qiang; Dong, Ke; Liu, Nannan

    2012-10-01

    A previous study identified 3 nonsynonymous and 6 synonymous mutations in the entire mosquito sodium channel of Culex quinquefasciatus, the prevalence of which were strongly correlated with levels of resistance and increased dramatically following insecticide selection. However, it is unclear whether this is unique to this specific resistant population or is a common mechanism in field mosquito populations in response to insecticide pressure. The current study therefore further characterized these mutations and their combinations in other field and permethrin selected Culex mosquitoes, finding that the co-existence of all 9 mutations was indeed correlated with the high levels of permethrin resistance in mosquitoes. Comparison of mutation combinations revealed several common mutation combinations presented across different field and permethrin selected populations in response to high levels of insecticide resistance, demonstrating that the co-existence of multiple mutations is a common event in response to insecticide resistance across different Cx. quinquefasciatus mosquito populations.

  5. In vivo functional genomic studies of sterol carrier protein-2 gene in the yellow fever mosquito.

    Science.gov (United States)

    Peng, Rong; Maklokova, Vilena I; Chandrashekhar, Jayadevi H; Lan, Que

    2011-03-18

    A simple and efficient DNA delivery method to introduce extrachromosomal DNA into mosquito embryos would significantly aid functional genomic studies. The conventional method for delivery of DNA into insects is to inject the DNA directly into the embryos. Taking advantage of the unique aspects of mosquito reproductive physiology during vitellogenesis and an in vivo transfection reagent that mediates DNA uptake in cells via endocytosis, we have developed a new method to introduce DNA into mosquito embryos vertically via microinjection of DNA vectors in vitellogenic females without directly manipulating the embryos. Our method was able to introduce inducible gene expression vectors transiently into F0 mosquitoes to perform functional studies in vivo without transgenic lines. The high efficiency of expression knockdown was reproducible with more than 70% of the F0 individuals showed sufficient gene expression suppression (mosquitoes.

  6. Anthropogenic impacts on mosquito populations in North America over the past century

    Science.gov (United States)

    Rochlin, Ilia; Faraji, Ary; Ninivaggi, Dominick V.; Barker, Christopher M.; Kilpatrick, A. Marm

    2016-12-01

    The recent emergence and spread of vector-borne viruses including Zika, chikungunya and dengue has raised concerns that climate change may cause mosquito vectors of these diseases to expand into more temperate regions. However, the long-term impact of other anthropogenic factors on mosquito abundance and distributions is less studied. Here, we show that anthropogenic chemical use (DDT; dichlorodiphenyltrichloroethane) and increasing urbanization were the strongest drivers of changes in mosquito populations over the last eight decades in areas on both coasts of North America. Mosquito populations have increased as much as tenfold, and mosquito communities have become two- to fourfold richer over the last five decades. These increases are correlated with the decay in residual environmental DDT concentrations and growing human populations, but not with temperature. These results illustrate the far-reaching impacts of multiple anthropogenic disturbances on animal communities and suggest that interactions between land use and chemical use may have unforeseen consequences on ecosystems.

  7. Mosquito repellents, effectiveness in preventing diseases and safety during pregnancy

    OpenAIRE

    Francisco José Roma Paumgartten; Isabella Fernandes Delgado

    2016-01-01

    Repelentes de insetos são tratamentos adjuvantes para prevenir doenças transmitidas por artrópodos incluindo malária e arboviroses (por exemplo, febre amarela, dengue, chikungunya, zika, encefalite do Nilo Ocidental e outras). Pelo menos duas dessas doenças transmitidas por mosquitos (malária e febre zika) foram associadas com desfechos adversos da gravidez como perdas gestacionais, baixo peso ao nascer e defeitos congênitos graves. Os sintomas e o prognóstico da malária, em particular a caus...

  8. Hypersensitivity pneumonitis due to residential mosquito-coil smoke exposure

    Institute of Scientific and Technical Information of China (English)

    Gopall Roshnee; CAO Guo-qiang; CHEN Hong

    2011-01-01

    We reported a previously healthy 25-year-old female patient who developed hypersensitivity pneumonitis following repeated exposures to the smoke of mosquito coils. The patient presented with vague symptoms of cough and fever for 3 days. Diagnostic criteria proposed for clinical use in this case included history, exposure to a recognized antigen, physical examination, consistent radiographic images, bronchoalveolar lavage and lung biopsy. Much symptomatic relief and better radiographic response were noted after short-term use of oral corticosteroid and removal of the offending antigen.

  9. A male-determining factor in the mosquito Aedes aegypti

    OpenAIRE

    Hall, Andrew Brantley; Basu, Sanjay; Jiang, Xiaofang; Qi, Yumin; Timoshevskiy, Vladimir A.; Biedler, James K.; Sharakhova, Maria V; Elahi, Rubayet; Michelle A E Anderson; Chen, Xiao-Guang; Sharakhov, Igor V.; Adelman, Zach N.; Tu, Zhijian

    2015-01-01

    Sex determination in the mosquito Aedes aegypti is governed by a dominant male-determining factor (M factor) located within a Y chromosome–like region called the M locus. Here, we show that an M-locus gene, Nix, functions as an M factor in A. aegypti. Nix exhibits persistent M linkage and early embryonic expression, two characteristics required of an M factor. Nix knockout with clustered regularly interspaced short palindromic repeats (CRISPR)–Cas9 resulted in largely feminized genetic males ...

  10. Sterculia guttata seeds extractives--an effective mosquito larvicide.

    Science.gov (United States)

    Katade, Sushama R; Pawar, Pushpa V; Wakharkar, Radhika D; Deshpande, Nirmala R

    2006-08-01

    The larvicidal activity of ethanol, chloroform and hexane soxhlet extracts obtained from S. guttata seeds was investigated against the IVth instar larvae of Dengue fever vector, Aedes aegypti and filarial vector, Culex quinquefasciatus. All extracts including fractions of ethanol extract exhibited 100% larval kill within 24 hr exposure period at 500 ppm concentration. Fraction A1 of ethanol was found to be most promising; its LC50 was 21.552 and 35.520 ppm against C. quinquefasciatus and A. aegypti respectively. Naturally occurring S. guttata seed derived fractions merit further study as potential mosquito larval control agents or lead compounds.

  11. Targeted mutagenesis in the malaria mosquito using TALE nucleases.

    Directory of Open Access Journals (Sweden)

    Andrea L Smidler

    Full Text Available Anopheles gambiae, the main mosquito vector of human malaria, is a challenging organism to manipulate genetically. As a consequence, reverse genetics studies in this disease vector have been largely limited to RNA interference experiments. Here, we report the targeted disruption of the immunity gene TEP1 using transgenic expression of Transcription-Activator Like Effector Nucleases (TALENs, and the isolation of several TEP1 mutant A. gambiae lines. These mutations inhibited protein production and rendered TEP1 mutants hypersusceptible to Plasmodium berghei. The TALEN technology opens up new avenues for genetic analysis in this disease vector and may offer novel biotechnology-based approaches for malaria control.

  12. Direct Broad-Range Detection of Alphaviruses in Mosquito Extracts

    Science.gov (United States)

    2007-11-25

    mosquito extracts Mark W. Eshoo a,⁎, Chris A. Whitehouse c,1, Scott T. Zoll a, Christian Massire a, Thuy-Trang D. Pennella a, Lawrence B. Blyn a...AR221D South Africa, 1959 M Tocora virus PE-70009 Peru, 1997 M NR, not reported. a Cell types: dec, duck embryo cells; sm, suckling mouse; v, Vero; gp...osquito From Mike Turell AF252264 BHK, baby hamster kidney; cef, chick embryo fibroblasts; gmk, green monkey Table 3 Base compositions of the RT-PCR

  13. Targeted mutagenesis in the malaria mosquito using TALE nucleases.

    Science.gov (United States)

    Smidler, Andrea L; Terenzi, Olivier; Soichot, Julien; Levashina, Elena A; Marois, Eric

    2013-01-01

    Anopheles gambiae, the main mosquito vector of human malaria, is a challenging organism to manipulate genetically. As a consequence, reverse genetics studies in this disease vector have been largely limited to RNA interference experiments. Here, we report the targeted disruption of the immunity gene TEP1 using transgenic expression of Transcription-Activator Like Effector Nucleases (TALENs), and the isolation of several TEP1 mutant A. gambiae lines. These mutations inhibited protein production and rendered TEP1 mutants hypersusceptible to Plasmodium berghei. The TALEN technology opens up new avenues for genetic analysis in this disease vector and may offer novel biotechnology-based approaches for malaria control.

  14. Immunization of mice with recombinant mosquito salivary protein D7 enhances mortality from subsequent West Nile virus infection via mosquito bite.

    Directory of Open Access Journals (Sweden)

    Krystle L Reagan

    Full Text Available BACKGROUND: Mosquito salivary proteins (MSPs modulate the host immune response, leading to enhancement of arboviral infections. Identification of proteins in saliva responsible for immunomodulation and counteracting their effects on host immune response is a potential strategy to protect against arboviral disease. We selected a member of the D7 protein family, which are among the most abundant and immunogenic in mosquito saliva, as a vaccine candidate with the aim of neutralizing effects on the mammalian immune response normally elicited by mosquito saliva components during arbovirus transmission. METHODOLOGY/PRINCIPAL FINDINGS: We identified D7 salivary proteins of Culex tarsalis, a West Nile virus (WNV vector in North America, and expressed 36 kDa recombinant D7 (rD7 protein for use as a vaccine. Vaccinated mice exhibited enhanced interferon-γ and decreased interleukin-10 expression after uninfected mosquito bite; however, we found unexpectedly that rD7 vaccination resulted in enhanced pathogenesis from mosquito-transmitted WNV infection. Passive transfer of vaccinated mice sera to naïve mice also resulted in increased mortality rates from subsequent mosquito-transmitted WNV infection, implicating the humoral immune response to the vaccine in enhancement of viral pathogenesis. Vaccinated mice showed decreases in interferon-γ and increases in splenocytes producing the regulatory cytokine IL-10 after WNV infection by mosquito bite. CONCLUSIONS/SIGNIFICANCE: Vector saliva vaccines have successfully protected against other blood-feeding arthropod-transmitted diseases. Nevertheless, the rD7 salivary protein vaccine was not a good candidate for protection against WNV disease since immunized mice infected via an infected mosquito bite exhibited enhanced mortality. Selection of salivary protein vaccines on the bases of abundance and immunogenicity does not predict efficacy.

  15. Integrating the public in mosquito management: active education by community peers can lead to significant reduction in peridomestic container mosquito habitats.

    Science.gov (United States)

    Healy, Kristen; Hamilton, George; Crepeau, Taryn; Healy, Sean; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M

    2014-01-01

    Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM) of Ae. albopictus is particularly difficult because it requires access to private yards in urban and suburban residences. It has become apparent that in the event of a public health concern due to this species, homeowners will have to be active participants in the control process by reducing mosquito habitats in their properties, an activity known as source reduction. However, limited attempts at quantifying the effect of source reduction by homeowners have had mixed results. Of note, many mosquito control programs in the US have some form of education outreach, however the primary approach is often passive focusing on the distribution of education materials as flyers. In 2010, we evaluated the use of active community peer education in a source reduction program, using AmeriCorps volunteers. The volunteers were mobilized over a 4-week period, in two areas with approximately 1,000 residences each in urban Mercer and suburban Monmouth counties in New Jersey, USA. The volunteers were first provided training on peridomestic mosquitoes and on basic approaches to reducing the number of container habitats for mosquito larvae in backyards. Within the two treatment areas the volunteers successfully engaged 758 separate homes. Repeated measures analysis of variance showed a significant reduction in container habitats in the sites where the volunteers actively engaged the community compared to untreated control areas in both counties. Our results suggest that active education using community peer educators can be an effective means of source reduction, and a critical tool in the arsenal

  16. Integrating the public in mosquito management: active education by community peers can lead to significant reduction in peridomestic container mosquito habitats.

    Directory of Open Access Journals (Sweden)

    Kristen Healy

    Full Text Available Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM of Ae. albopictus is particularly difficult because it requires access to private yards in urban and suburban residences. It has become apparent that in the event of a public health concern due to this species, homeowners will have to be active participants in the control process by reducing mosquito habitats in their properties, an activity known as source reduction. However, limited attempts at quantifying the effect of source reduction by homeowners have had mixed results. Of note, many mosquito control programs in the US have some form of education outreach, however the primary approach is often passive focusing on the distribution of education materials as flyers. In 2010, we evaluated the use of active community peer education in a source reduction program, using AmeriCorps volunteers. The volunteers were mobilized over a 4-week period, in two areas with approximately 1,000 residences each in urban Mercer and suburban Monmouth counties in New Jersey, USA. The volunteers were first provided training on peridomestic mosquitoes and on basic approaches to reducing the number of container habitats for mosquito larvae in backyards. Within the two treatment areas the volunteers successfully engaged 758 separate homes. Repeated measures analysis of variance showed a significant reduction in container habitats in the sites where the volunteers actively engaged the community compared to untreated control areas in both counties. Our results suggest that active education using community peer educators can be an effective means of source reduction, and a critical

  17. Contrasting patterns of tolerance between chemical and biological insecticides in mosquitoes exposed to UV-A.

    Science.gov (United States)

    Tetreau, Guillaume; Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud'homme, Sophie M; Raveton, Muriel; Reynaud, Stéphane

    2013-09-15

    Mosquitoes are vectors of major human diseases, such as malaria, dengue or yellow fever. Because no efficient treatments or vaccines are available for most of these diseases, control measures rely mainly on reducing mosquito populations by the use of insecticides. Numerous biotic and abiotic factors are known to modulate the efficacy of insecticides used in mosquito control. Mosquito breeding sites vary from opened to high vegetation covered areas leading to a large ultraviolet gradient exposure. This ecological feature may affect the general physiology of the insect, including the resistance status against insecticides. In the context of their contrasted breeding sites, we assessed the impact of low-energetic ultraviolet exposure on mosquito sensitivity to biological and chemical insecticides. We show that several mosquito detoxification enzyme activities (cytochrome P450, glutathione S-transferases, esterases) were increased upon low-energy UV-A exposure. Additionally, five specific genes encoding detoxification enzymes (CYP6BB2, CYP6Z7, CYP6Z8, GSTD4, and GSTE2) previously shown to be involved in resistance to chemical insecticides were found over-transcribed in UV-A exposed mosquitoes, revealed by RT-qPCR experiments. More importantly, toxicological bioassays revealed that UV-exposed mosquitoes were more tolerant to four main chemical insecticide classes (DDT, imidacloprid, permethrin, temephos), whereas the bioinsecticide Bacillus thuringiensis subsp. israelensis (Bti) appeared more toxic. The present article provides the first experimental evidence of the capacity of low-energy UV-A to increase mosquito tolerance to major chemical insecticides. This is also the first time that a metabolic resistance to chemical insecticides is linked to a higher susceptibility to a bioinsecticide. These results support the use of Bti as an efficient alternative to chemical insecticides when a metabolic resistance to chemicals has been developed by mosquitoes.

  18. Converting Mosquito Surveillance to Arbovirus Surveillance with Honey-Baited Nucleic Acid Preservation Cards.

    Science.gov (United States)

    Flies, Emily J; Toi, Cheryl; Weinstein, Philip; Doggett, Stephen L; Williams, Craig R

    2015-07-01

    Spatially and temporally accurate information about infectious mosquito distribution allows for pre-emptive public health interventions that can reduce the burden of mosquito-borne infections on human populations. However, the labile nature of arboviruses, the low prevalence of infection in mosquitoes, the expensive labor costs for mosquito identification and sorting, and the specialized equipment required for arbovirus testing can obstruct arbovirus surveillance efforts. The recently developed techniques of testing mosquito expectorate using honey-baited nucleic acid preservation cards or sugar bait stations allows a sensitive method of testing for infectious, rather than infected, mosquito vectors. Here we report the results from the first large-scale incorporation of honey-baited cards into an existing mosquito surveillance program. During 4 months of the peak virus season (January-April, 2014) for a total of 577 trap nights, we set CO2-baited encephalitis vector survey (EVS) light traps at 88 locations in South Australia. The collection container for the EVS trap was modified to allow for the placement of a honey-baited nucleic acid preservation card (FTA™ card) inside. After collection, mosquitoes were maintained in a humid environment and allowed access to the cards for 1 week. Cards were then analyzed for common endemic Australian arboviruses using a nested RT-PCR. Eighteen virus detections, including 11 Ross River virus, four Barmah Forest virus, and three Stratford virus (not previously reported from South Australia) were obtained. Our findings suggest that adding FTA cards to an existing mosquito surveillance program is a rapid and efficient way of detecting infectious mosquitoes with high spatial resolution.

  19. Studies on mid gut microbiota of wild caught Culex (Culex quinquefasciatus mosquitoes from Barasat (North 24 Parganas of West Bengal.

    Directory of Open Access Journals (Sweden)

    Abhishek Pal

    2014-06-01

    Full Text Available Mosquitoes are haematophagous insects that serve as obligate intermediate host for numerous diseases like Filaria, Malaria, Dengue, etc. Mosquitoes can be considered as a holobiont units in which host (mosquitoes and its gut microbiota are involved in a complex reciprocal interaction. The naturally acquired microbiota can modulate mosquitos’ vectorial capacity by inhibiting the development of pathogens. But, enough care has not been taken in West Bengal to investigate on the midgut microbiota of Culex mosquitoes. Therefore, a preliminary attempt has been undertaken to study the morphology, growth pattern and antibiotic susceptibility of midgut microbiota of Culex (Culex quinquefasciatus mosquitoes collected from Barasat areas (North 24 Parganas of West Bengal..

  20. Biolistic techniques for transfection of mosquito embryos (Anopheles gambiae).

    Science.gov (United States)

    Mialhe, E; Miller, L H

    1994-05-01

    To compensate for the extremely low rates of transformation by DNA microinjection into mosquito embryos of Anopheles gambiae, biolistic techniques were evaluated for introduction of DNA into large numbers of mosquito embryos. Biolistic experiments were first performed with a commercially available instrument intended for this purpose, according to the recommended procedure. The amount of DNA delivered was measured by the expression of luciferase under the control of the Drosophila heat shock protein (hsp) 70 promoter. Despite attempts to optimize biolistic parameters, the level of luciferase activity was low and highly variable. Two other methods of biolistic delivery of DNA-coated particles in aqueous suspension were then evaluated. One method used the gas explosion of the commercially available instrument (mentioned above) to drive an aqueous suspension of DNA-coated particles at high pressure. This method reproducibly increased the level of expression about 100-fold without greatly reducing embryo viability. Another method, which was recently described for plant transfection, uses lower pressure to deliver the aqueous suspension of DNA-coated particles. The level of expression of luciferase and the survival of embryos were equivalent to that obtained with the instrument modified for aqueous delivery of particles. Thus, both aqueous methods offer the advantages of reproducibly delivering more DNA to the embryos. Moreover, these methods could be suitable for delivering DNA mixed with proteins, such as restriction endonucleases and integrases, that may be destroyed by ethanol precipitation used in the standard PDS-1000/He method.