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Sample records for culex quinquefasciatus diptera

  1. The distribution of potential West Nile virus vectors, Culex pipiens pipiens and Culex pipiens quinquefasciatus (Diptera: Culicidae), in Mexico City.

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    Diaz-Badillo, Alvaro; Bolling, Bethany G; Perez-Ramirez, Gerardo; Moore, Chester G; Martinez-Munoz, Jorge P; Padilla-Viveros, America A; Camacho-Nuez, Minerva; Diaz-Perez, Alfonso; Beaty, Barry J; Munoz, Maria de Lourdes

    2011-05-09

    Culex spp. mosquitoes are considered to be the most important vectors of West Nile virus (WNV) detected in at least 34 species of mosquitoes in the United States. In North America, Culex pipiens pipiens, Culex pipiens quinquefasciatus, and Culex tarsalis are all competent vectors of WNV, which is considered to be enzootic in the United States and has also been detected in equines and birds in many states of Mexico and in humans in Nuevo Leon. There is potential for WNV to be introduced into Mexico City by various means including infected mosquitoes on airplanes, migrating birds, ground transportation and infected humans. Little is known of the geographic distribution of Culex pipiens complex mosquitoes and hybrids in Mexico City. Culex pipiens pipiens preferentially feed on avian hosts; Culex pipiens quinquefasciatus have historically been considered to prefer mammalian hosts; and hybrids of these two species could theoretically serve as bridge vectors to transmit WNV from avian hosts to humans and other mammalian hosts. In order to address the potential of WNV being introduced into Mexico City, we have determined the identity and spatial distribution of Culex pipiens complex mosquitoes and their hybrids. Mosquito larvae collected from 103 sites throughout Mexico City during 2004-2005 were identified as Culex, Culiseta or Ochlerotatus by morphological analysis. Within the genus Culex, specimens were further identified as Culex tarsalis or as belonging to the Culex pipiens complex. Members of the Culex pipiens complex were separated by measuring the ratio of the dorsal and ventral arms (DV/D ratio) of the male genitalia and also by using diagnostic primers designed for the Ace.2 gene. Culex pipiens quinquefasciatus was the most abundant form collected. Important WNV vectors species, Cx. p. pipiens, Cx. p. quinquefasciatus and Cx. tarsalis, are all present in Mexico City. Hybrids of Cx. p. pipiens and Cx. p. quinquefasciatus were also collected and identified. The

  2. The distribution of potential West Nile virus vectors, Culex pipiens pipiens and Culex pipiens quinquefasciatus (Diptera: Culicidae, in Mexico City

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    Diaz-Perez Alfonso

    2011-05-01

    Full Text Available Abstract Background Culex spp. mosquitoes are considered to be the most important vectors of West Nile virus (WNV detected in at least 34 species of mosquitoes in the United States. In North America, Culex pipiens pipiens, Culex pipiens quinquefasciatus, and Culex tarsalis are all competent vectors of WNV, which is considered to be enzootic in the United States and has also been detected in equines and birds in many states of Mexico and in humans in Nuevo Leon. There is potential for WNV to be introduced into Mexico City by various means including infected mosquitoes on airplanes, migrating birds, ground transportation and infected humans. Little is known of the geographic distribution of Culex pipiens complex mosquitoes and hybrids in Mexico City. Culex pipiens pipiens preferentially feed on avian hosts; Culex pipiens quinquefasciatus have historically been considered to prefer mammalian hosts; and hybrids of these two species could theoretically serve as bridge vectors to transmit WNV from avian hosts to humans and other mammalian hosts. In order to address the potential of WNV being introduced into Mexico City, we have determined the identity and spatial distribution of Culex pipiens complex mosquitoes and their hybrids. Results Mosquito larvae collected from 103 sites throughout Mexico City during 2004-2005 were identified as Culex, Culiseta or Ochlerotatus by morphological analysis. Within the genus Culex, specimens were further identified as Culex tarsalis or as belonging to the Culex pipiens complex. Members of the Culex pipiens complex were separated by measuring the ratio of the dorsal and ventral arms (DV/D ratio of the male genitalia and also by using diagnostic primers designed for the Ace.2 gene. Culex pipiens quinquefasciatus was the most abundant form collected. Conclusions Important WNV vectors species, Cx. p. pipiens, Cx. p. quinquefasciatus and Cx. tarsalis, are all present in Mexico City. Hybrids of Cx. p. pipiens and Cx. p

  3. Baseline Susceptibility of Filarial Vector Culex quinquefasciatus (Diptera: Cu-licidae to Five Insecticides with Different Modes of Action in Southeast of Iran

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    Yaser Salim-Abadi

    2017-12-01

    Full Text Available Background: Culex quinquefasciatus (Diptera: Culicidae is an important vector for many human diseases. The aim of this study was to evaluate the susceptibility level of larval and adult stages of Cu. quinquefasciatus to different groups of WHO recommended insecticides for vector control.Methods: Larval stages of the Culex mosquitoes were collected from their natural habitats in Rafsanjan County at Kerman Province, southeast of Iran in 2016. Insecticide susceptibility status of adult female Cx. quinquefasciatus against DDT (4%, deltamethrin (0.05%, malathion 5%, and bendiocarb (0.1% were determined using WHO stand­ard insecticide susceptibility test. Additional test was carried out to determine the susceptibility status of larvae of Cx. quinquefasciatus to temephos. Bioassay data were analyzed by Probit program.Results: Cx. quinquefasciatus adults showed resistance to all four groups of the tested insecticides according to the WHO criteria for resistance evaluation. The lethal concentrations for 50% mortality (LC50 and 90% mortality (LC90 of temephos against Cx. quinquefasciatus larvae were 0.18mg/l and 0.78mg/l, respectively. This finding also con­firms resistance to temephos based on the WHO recommended instructions for resistance evaluation.Conclusion: Resistance to all groups of the tested insecticides should be considered for future vector control investi­gations in the study area.

  4. Culex quinquefasciatus (Diptera: Culicidae From Florida Transmitted Zika Virus

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    Chelsea T. Smartt

    2018-04-01

    Full Text Available We report a laboratory colony of Culex quinquefasciatus mosquitoes were experimentally able to salivate Zika virus (ZIKV, Flaviviridae; Flavivirus at 16 days post infection (dpi. ZIKV RNA was detected in bodies and in saliva deposited on filter paper cards with subsequent studies demonstrating the presence of live ZIKV in saliva.

  5. Laboratory and field evaluation of an oviposition trap for Culex quinquefasciatus(Diptera: Culicidae

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    Rosângela MR Barbosa

    2007-06-01

    Full Text Available An ovitrap (BR-OVT based on physical and chemical stimuli for attracting gravid Culex quinquefasciatus (Diptera: Culicidae females was developed and evaluated under laboratory and field conditions. Attractants were assayed using alternative chamber bioassays prior to being used in the BR-OVT oviposition trap. A significant preference of gravid females for sites containing conspecific egg rafts was observed, as a response to the natural oviposition pheromone, as well as for sites treated with the synthetic pheromone erythro-6-acetoxy-5-hexadecanolide. Five- to 20-day old grass infusion was strongly attractive to gravid females for laying eggs. On the other hand, entomopathogenic Bacillus sphaericus (Bs did not influence the choice of an oviposition site when used in combination with grass infusion and can therefore be used as a larvicide in ovitraps. Results from field trials showed that the BR-OVT with grass infusion and with or without Bs works as a preferred oviposition site for Cx. quinquefasciatus. The BR-OVT was more effective for egg collection when placed indoors and comparison with the number of egg rafts laid in cesspits over 40 days indicates that this very simple ovitrap may be a useful tool for monitoring populations of the most important of the vectors of bancroftian filariasis.

  6. Feeding patterns of Culex quinquefasciatus (Diptera: Culicidae) from eastern Santa Catarina state, Brazil.

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    Alencar, Jeronimo; Silva, Júlia dos Santos; de Oliveira, Luis Claudio Motta; Marcondes, Carlos Brisola; Morone, Fernanda; Lorosa, Elias Seixas

    2012-07-01

    Blood-feeding sources of Culex quinquefasciatus Say (Diptera: Culicidae) collected in the eastern region of the Brazilian state of Santa Catarina were analyzed by precipitin technique. One hundred fifty-four female mosquitoes collected by CDC traps in the Navegantes municipality 13-15 February 2005 reacted to one or more of eight antisera, including chicken, dog, goat, sheep, horse, opossum, human and rodent antisera. One hundred thirty-seven specimens (89%) reacted to only one source, and 17 (11%) specimens reacted to two sources. Among the 137 specimens reacting to only one source, reactions to rodent (50.4%), sheep (5.8%), chicken (5.1%), goat (5.1%), dog (2.2%), horse (3.6%), and human (3.6%) antisera were observed. The analyzed species demonstrated a high degree of opportunistic feeding behavior in relation to host preference. Results are compared with results from similar studies, and the low proportion of reactions to human antisera is discussed.

  7. Exploring genetic variation in haplotypes of the filariasis vector Culex quinquefasciatus (Diptera: Culicidae) through DNA barcoding.

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    Vadivalagan, Chithravel; Karthika, Pushparaj; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Del Serrone, Paola; Benelli, Giovanni

    2017-05-01

    Culex quinquefasciatus (Diptera: Culicidae) is a vector of many pathogens and parasites of humans, as well as domestic and wild animals. In urban and semi-urban Asian countries, Cx. quinquefasciatus is a main vector of nematodes causing lymphatic filariasis. In the African region, it vectors the Rift Valley fever virus, while in the USA it transmits West Nile, St. Louis encephalitis and Western equine encephalitis virus. In this study, DNA barcoding was used to explore the genetic variation of Cx. quinquefasciatus populations from 88 geographical regions. We presented a comprehensive approach analyzing the effectiveness of two gene markers, i.e. CO1 and 16S rRNA. The high threshold genetic divergence of CO1 (0.47%) gene was reported as an ideal marker for molecular identification of this mosquito vector. Furthermore, null substitutions were lower in CO1 if compared to 16S rRNA, which influenced its differentiating potential among Indian haplotypes. NJ tree was well supported with high branch values for CO1 gene than 16S rRNA, indicating ideal genetic differentiation among haplotypes. TCS haplotype network revealed 14 distinct clusters. The intra- and inter-population polymorphism were calculated among the global and Indian Cx. quinquefasciatus lineages. The genetic diversity index Tajima' D showed negative values for all the 4 intra-population clusters (G2-4, G10). Fu's FS showed negative value for G10 cluster, which was significant and indicated recent population expansion. However, the G2-G4 (i.e. Indian lineages) had positive values, suggesting a bottleneck effect. Overall, our research firstly shed light on the genetic differences among the haplotypes of Cx. quinquefasciatus species complex, adding basic knowledge to the molecular ecology of this important mosquito vector. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Effect of photoperiod on blood feeding activity of female hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus (Diptera: Culicidae)

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    Kurokawa, Kenji; Yoshii, Manabu; Oda, Tsutomu; Kato, Katsutomo; Uchida, Keikichi; Eshita, Yuki; Tahara, Hiroyuki; Mine, Mariko; Ogawa, Yasunori

    2004-01-01

    Blood feeding activity was examined in females of hybrids (F1) between Culex pipiens pipiens and Culex pipiens quinquefasciatus in long and short photoperiods at 2l℃ to examine the effect of photoperiod on blood feeding rate. Blood feeding rates (F1) were lower in short photoperiods than in long photoperiods. From this, it seems that the hybrids show diapause.

  9. Larval habitat for the avian malaria vector culex quinquefasciatus (Diptera: Culicidae) in altered mid-elevation mesic-dry forests in Hawai'i

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    Reiter, M.E.; Lapointe, D.A.

    2009-01-01

    Effective management of avian malaria (Plasmodium relictum) in Hawai'i's endemic honeycreepers (Drepanidinae) requires the identification and subsequent reduction or treatment of larval habitat for the mosquito vector, Culex quinquefasciatus (Diptera: Culicidae). We conducted ground surveys, treehole surveys, and helicopter aerial surveys from 20012003 to identify all potential larval mosquito habitat within two 100+ ha mesic-dry forest study sites in Hawai'i Volcanoes National Park, Hawai'i; 'Ainahou Ranch and Mauna Loa Strip Road. At 'Ainahou Ranch, anthropogenic sites (43%) were more likely to contain mosquitoes than naturally occurring (8%) sites. Larvae of Cx. quinquefasciatus were predominately found in anthropogenic sites while Aedes albopictus larvae occurred less frequently in both anthropogenic sites and naturally-occurring sites. Additionally, moderate-size (???20-22,000 liters) anthropogenic potential larval habitat had >50% probability of mosquito presence compared to larger- and smaller-volume habitat (malaria, may be controlled by larval habitat reduction in the mesic-dry landscapes of Hawai'i where anthropogenic sources predominate.

  10. Mosquito larvicidal and ovicidal properties of Pithecellobium dulce (Roxb.) Benth. (Fabaceae) against Culex quinquefasciatus Say (Diptera: Culicidae)

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    Govindarajan Marimuthu; Rajeswary Mohan

    2014-01-01

    Objective: To assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant, Pithecellobium dulce (P. dulce) against filariasis vector mosquito, Culex quinquefasciatus (Cx. quinquefasciatus). Methods: Twenty five early third instar larvae of Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO (2005). The larval mor...

  11. Identification of Blood Meal Sources in Aedes vexans and Culex quinquefasciatus in Bernalillo County, New Mexico

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    Greenberg, Jacob A.; Lujan, Daniel A.; DiMenna, Mark A.; Wearing, Helen J.; Hofkin, Bruce V.

    2013-01-01

    Culex quinquefasciatus Say (Diptera: Culicidae) and Aedes vexans Meigen are two of the most abundant mosquitoes in Bernalillo County, New Mexico, USA. In this study, a polymerase chain reaction based methodology was used to identify the sources of blood meals taken by these two species. Ae. vexans was found to take a large proportion of its meals from mammals. Although less specific in terms of its blood meal preferences, Cx. quinquefasciatus was found to feed more commonly on birds. The results for Ae. vexans are similar to those reported for this species in other parts of their geographic range. Cx. quinquefasciatus appears to be more variable in terms of its host feeding under different environmental or seasonal circumstances. The implications of these results for arbovirus transmission are discussed. PMID:24224615

  12. Olfactory memory in the mosquito Culex quinquefasciatus.

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    McCall, P J; Eaton, G

    2001-06-01

    The cosmotropical urban mosquito Culex quinquefasciatus Say (Diptera: Culicidae) uses chemical cues to locate suitable water pools for oviposition. Although gravid females are innately attracted to or repelled by certain compounds, this study found that an individual mosquito's preferences for these odours could be altered greatly by prior experience. Mosquitoes reared in water containing skatole, at a level normally repellent to ovipositing females, preferred to oviposit in water containing that compound rather than in water with an otherwise attractive odour compound (P-cresol). This behaviour occurred regardless of whether mosquitoes were tested individually or in groups of up to 50 per cage. The F1 progeny of conditioned mosquitoes did not exhibit the parental preference, but were as susceptible to conditioning as their parents. Moreover, rearing mosquitoes in infusions of hay or animal (guinea-pig) faeces produced a similar although less dramatic change, such that the innate propensity for hay infusion could be cancelled by rearing in guinea-pig faeces infusion. The results demonstrated a change in odour preference by Cx. quinquefasciatus following exposure to the odour during development or pupal eclosion, suggesting that some form of larval conditioning or early adult imprinting occurred. Precisely when that conditioning occurred remains to be determined.

  13. Human Blood Feeding Activity of Female Hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus(Diptera: Culicidae)

    OpenAIRE

    Yoshii, Manabu; Mine, Mariko; Kurokawa, Kenji; Oda, Tsutomu; Kato, Katsutomo; Ogawa, Yasunori; Eshita, Yuuki; Uchida, Keikichi

    2007-01-01

    Human blood feeding activity was examined in females of hybrids between Culex pipiens pipiens and Culex pipiens quinquefasciatus during long photoperiod at 25℃. Blood feeding rates of hybrids were lower than in Culex pipiens quinquefasciatus and Culex pipiens pallens, and higher than in Culex pipiens pipiens, because no females fed on human blood in Culex pipiens pipiens.

  14. Larvicidal activity of Nerium oleander L. (Apocynaceae flower extracts against Culex quinquefasciatus Say (Diptera: Culicidae

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    R. Raveen

    2014-03-01

    Full Text Available Culex quinquefasciatus is the vector responsible for serious disease filariasis among human beings. Plant derived products have received increased attention from scientists as they serve as a rich source for novel natural substances possessing insecticidal properties which are safe to human and ecosystem. During the last decade, various studies on natural plant products against vector mosquito indicate them as possible alternatives to chemical and synthetic insecticides for mosquito control. In the present study, the crude hexane and aqueous extract of Nerium oleander flowers were reported for larvicidal activity against the filarial vector, Culex quinquefasciatus. Mortality was observed for 24 and 48 hours. Hexane flower extract exhibited highest larvicidal activity with a LC50 value of 102.54 ppm and 61.11ppm after 24 and 48 hours respectively. Further investigations are needed to elucidate this activity against a wide range of all stages of mosquito species and also the active ingredient(s of the extract responsible for larvicidal activity should be identified.

  15. Laboratory and field evaluation of medicinal plant extracts against filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae)

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    In this study, chemical extracts of Jatropha curcas, Hyptis suaveolens, Abutilon indicum, and Leucas aspera were tested for toxicity to larvae of the filariasis vector Culex quinquefasciatus. Respective median lethal concentrations (LC50) for hexane, chloroform, ethyl acetate, and methanol extracts...

  16. Asymmetrical Competition between Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae Coexisting in Breeding Sites

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    Juan C. Santana-Martínez

    2017-10-01

    Full Text Available Aedes aegypti and Culex quinquefasciatus are mosquito vectors for several tropical diseases that represent a current public health problem. The ecological requirements for each species are different, however, both species show high biological adaptability, which promotes their coexistence in the same breeding sites. The purpose of this study was to assess the effect of larval association between Ae. aegypti and Cx. quinquefasciatus under different laboratory conditions of food supply and temperature, and under field simulated conditions like peridomestic containers. Our findings showed that under field simulated conditions there was no asymmetrical competition in mixed cultures with the different Cx. quinquefasciatus/Ae. aegypti ratios tested. However, under laboratory conditions in which different doses of food supply were evaluated, it was observed that competition between the two species takes place. Larval coexistence under food scarcity conditions (0.95 mg/larva showed that Ae. aegypti had a greater adult emergence than Cx. quinquefasciatus and was capable of depriving Cx. quinquefasciatus of the food needed to complete metamorphosis. In an intermediate dose of food (1.9 mg/larva, the dry weight of Cx. quinquefasciatus adults decreased, and their larval development time increased when Cx. quinquefasciatus/Ae. aegypti ratio was low. Also, a temperature effect was assessed demonstrating that Cx. quinquefasciatus was more vulnerable to changes in temperature. We suggest that Ae. aegypti is more successful in exploiting microhabitats when food is scarce, due to its scrape active feeding habitats and fast larval development times. Therefore, in conditions of food paucity both species will compete, and Ae. aegypti larvae will prevail.

  17. Effects of blood meal source on the reproduction of Culex pipiens quinquefasciatus (Diptera: Culicidae).

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    Richards, Stephanie L; Anderson, Sheri L; Yost, Samantha A

    2012-06-01

    Culex pipiens quinquefasciatus were fed blood meals from a live chicken (LC), chicken blood in Alsever's (AC) solution, defibrinated bovine blood (DB), or bovine blood in citrate (CB) and incubated at 28° C. The effects of different blood meal sources were evaluated with respect to rates of blood feeding and reproduction (i.e., fecundity and fertility) over two gonotrophic cycles. Mosquitoes that fed on the first blood meal were subjected to a second blood meal as follows (first blood meal / second blood meal): LC/LC, LC/DB, DB/DB, CB/CB, AC/AC. Fecundity and fertility of Cx. p. quinquefasciatus were significantly (P blood; however, fecundity and fertility in different treatment groups varied by gonotrophic cycle. These results contribute to our understanding of the impact of blood meal source on feeding and reproduction in Cx. p. quinquefasciatus. The potential impacts of blood meal source on virus transmission experiments are discussed. © 2012 The Society for Vector Ecology.

  18. Toxic Response of Mosquito Culex Quinquefasciatus (Diptera: Culicidae to some Agricultural Pesticides (Butachlor and Pertilachlor

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    Aliakbar Hedayati*

    2017-06-01

    Full Text Available Background: The expansion of herbicide used in aquatic ecosystems as well as in terrestrial if is not properly controlled may produce harmful effects on freshwater fisheries. Residue limits of these agricultural chemicals in tropical fishery waters should be established. The aim of this study was to determine the acute toxicity of butachlor and pertilachlor as potential dangerous herbicides to assess mortality effects of these chemicals to the Mosquito Culex quinquefasciatus. Methods: This study was carried out in Gorgan University of Agricultural Sciences and Natural Resources, Gorgan, Iran at summer 2013. Culex samples were exposed to different concentrations of butachlor and pertilachlor (0-200ppm for butachlor and pertilachlor for 96 h. Results: The low toxicity of LC50s obtained for butachlor (23.81±0.04 and pertilachlor (27.97±0.05 indicate that butachlor and pertilachlor were lowly toxic to Mosquito Cu. quinquefasciatus. Conclusion: Although pretilachlor and butachlor are low toxic but pretilachlor is less toxic in field conditions, these data are useful to potential ecosystem risk assessment.

  19. Bionomics of Culex quinquefasciatus within urban areas of Rio de Janeiro, Southeastern Brazil

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    Mariana Rocha David

    2012-10-01

    Full Text Available OBJECTIVE: To evaluate density, parity rates, daily survival and longevity of natural populations of Culex quinquefasciatus in three neighborhoods with distinct socio-economic and infrastructure profiles. METHODS: Mosquito collections of the Culex quinquefasciatus species were performed weekly during two four month periods, from August to November 2008 (spring and March to June 2009 (fall, in a favela (slum, a suburban area and a middle class area of Rio de Janeiro, Southeastern Brazil. Collections were performed with backpack aspirators, in 20 randomly selected houses in each area per week, during 15-20 minutes per house. Ovaries were removed from captured females and classified as initial, intermediary or final stage. Furthermore, females were dissected for determination of parity based on the condition of the tracheal system. Mosquito survival rate and longevity were estimated on a per month basis for each neighborhood. RESULTS: We collected a total of 2,062 Culex quinquefasciatus, but monthly vector density was not correlated with temperature and rainfall. We dissected the ovaries of 625 Culex quinquefasciatus, and overall, there was a higher proportion of nulliparous females during the dryer months, while gravid females were more frequent in rainy months. In the middle class neighborhood, the parity rate reached up to 93.75% with survivorship of 0.979. Lower parity and survival rates were obtained in the suburban area (as low as 36.4% parity and 0.711 daily survival. Up to 84.7% of Culex quinquefasciatus females could survive the eight day period needed to complete West Nile Virus incubation. CONCLUSIONS: The survival rate of Culex quinquefasciatus varied significantly between the neighborhoods. This suggests that vectorial capacity and disease transmission risk may vary greatly between different urban areas, which is potentially useful information for vector control programs.

  20. Mitochondrial DNA analyses reveal low genetic diversity in Culex quinquefasciatus from residential areas in Malaysia.

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    Low, V L; Lim, P E; Chen, C D; Lim, Y A L; Tan, T K; Norma-Rashid, Y; Lee, H L; Sofian-Azirun, M

    2014-06-01

    The present study explored the intraspecific genetic diversity, dispersal patterns and phylogeographic relationships of Culex quinquefasciatus Say (Diptera: Culicidae) in Malaysia using reference data available in GenBank in order to reveal this species' phylogenetic relationships. A statistical parsimony network of 70 taxa aligned as 624 characters of the cytochrome c oxidase subunit I (COI) gene and 685 characters of the cytochrome c oxidase subunit II (COII) gene revealed three haplotypes (A1-A3) and four haplotypes (B1-B4), respectively. The concatenated sequences of both COI and COII genes with a total of 1309 characters revealed seven haplotypes (AB1-AB7). Analysis using tcs indicated that haplotype AB1 was the common ancestor and the most widespread haplotype in Malaysia. The genetic distance based on concatenated sequences of both COI and COII genes ranged from 0.00076 to 0.00229. Sequence alignment of Cx. quinquefasciatus from Malaysia and other countries revealed four haplotypes (AA1-AA4) by the COI gene and nine haplotypes (BB1-BB9) by the COII gene. Phylogenetic analyses demonstrated that Malaysian Cx. quinquefasciatus share the same genetic lineage as East African and Asian Cx. quinquefasciatus. This study has inferred the genetic lineages, dispersal patterns and hypothetical ancestral genotypes of Cx. quinquefasciatus. © 2013 The Royal Entomological Society.

  1. Sampling gravid Culex quinquefasciatus (Diptera: Culicidae) in Tanzania with traps baited with synthetic oviposition pheromone and grass infusions

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    Mboera, L.E.G.; Takken, W.; Mdira, K.Y.; Pickett, J.A.

    2000-01-01

    The effectiveness of traps baited with (5R,6S)-6-acetoxy-5-hexadecanolide (the synthetic oviposition pheromone) and grass infusions in sampling a population of gravid Culex quinquefasciatus Say was conducted in Muheza, Northeast Tanzania. A counterflow geometry (CFG) trap baited with pheromone and

  2. Transmission of West Nile virus by Culex quinquefasciatus say infected with Culex Flavivirus Izabal.

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    Rebekah J Kent

    Full Text Available BACKGROUND: The natural history and potential impact of mosquito-specific flaviviruses on the transmission efficiency of West Nile virus (WNV is unknown. The objective of this study was to determine whether or not prior infection with Culex flavivirus (CxFV Izabal altered the vector competence of Cx. quinquefasciatus Say for transmission of a co-circulating strain of West Nile virus (WNV from Guatemala. METHODS AND FINDINGS: CxFV-negative Culex quinquefasciatus and those infected with CxFV Izabal by intrathoracic inoculation were administered WNV-infectious blood meals. Infection, dissemination, and transmission of WNV were measured by plaque titration on Vero cells of individual mosquito bodies, legs, or saliva, respectively, two weeks following WNV exposure. Additional groups of Cx. quinquefasciatus were intrathoracically inoculated with WNV alone or WNV+CxFV Izabal simultaneously, and saliva collected nine days post inoculation. Growth of WNV in Aedes albopictus C6/36 cells or Cx. quinquefasciatus was not inhibited by prior infection with CxFV Izabal. There was no significant difference in the vector competence of Cx. quinquefasciatus for WNV between mosquitoes uninfected or infected with CxFV Izabal across multiple WNV blood meal titers and two colonies of Cx. quinquefasciatus (p>0.05. However, significantly more Cx. quinquefasciatus from Honduras that were co-inoculated simultaneously with both viruses transmitted WNV than those inoculated with WNV alone (p = 0.0014. Co-inoculated mosquitoes that transmitted WNV also contained CxFV in their saliva, whereas mosquitoes inoculated with CxFV alone did not contain virus in their saliva. CONCLUSIONS: In the sequential infection experiments, prior infection with CxFV Izabal had no significant impact on WNV replication, infection, dissemination, or transmission by Cx. quinquefasciatus, however WNV transmission was enhanced in the Honduras colony when mosquitoes were inoculated simultaneously with

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

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    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2014-04-01

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

  4. Treatment of horses with cypermethrin against the biting flies Culicoides nubeculosus, Aedes aegypti and Culex quinquefasciatus.

    Science.gov (United States)

    Papadopoulos, E; Rowlinson, M; Bartram, D; Carpenter, S; Mellor, P; Wall, R

    2010-04-19

    An in vitro assay was used to assess the efficacy of the proprietary pyrethroid insecticide cypermethrin applied to horses (Deosect spray, 5.0%, w/v Fort Dodge Animal Health) against the biting midge Culicoides nubeculosus (Meigen) (Diptera: Ceratopogonidae) and the mosquitoes Aedes aegypti Linneaus and Culex quinquefasciatus Say (Diptera: Culicidae). Hair was collected from the back, belly and legs of the horses immediately prior to treatment and 7, 14, 21, 28 and 35 days after treatment, and also from untreated controls. In laboratory assays groups of 10 adult female C. nubeculosus, Ae. aegypti or C. quinquefasciatus were exposed to 0.5g of hair for 3min. In all cases, little or no mortality was observed in insects kept in contact with the pre-treatment samples or the untreated controls. With post-treatment samples for C. nubeculosus, mortality was close to 80% 7 days after treatment and then declined gradually; mean mortality was still at around 50% for hair collected 35 days after treatment. In general, Ae. aegypti and C. quinquefasciatus appeared to be less susceptible to cypermethrin than C. nubeculosus and the attenuation of the toxic effect declined more quickly with time after treatment. There were differences in the toxicity of hair from different body regions, with hair from the back consistently inducing the highest mortality and hair from the legs the lowest; this effect was more pronounced for C. nubeculosus than Ae. aegypti or C. quinquefasciatus. The results demonstrate the potential for topical insecticide treatment to offer protection to horses against biting flies; but highlight the major differences that exist in susceptibility between different insect species.

  5. Environmental and biological factors influencing Culex pipiens quinquefasciatus (Diptera: Culicidae) vector competence for West Nile Virus.

    Science.gov (United States)

    Richards, Stephanie L; Lord, Cynthia C; Pesko, Kendra N; Tabachnick, Walter J

    2010-07-01

    Interactions between environmental and biological factors affect the vector competence of Culex pipiens quinquefasciatus for West Nile virus. Three age cohorts from two Cx. p. quinquefasciatus colonies were fed blood containing a low- or high-virus dose, and each group was held at two different extrinsic incubation temperatures (EIT) for 13 days. The colonies differed in the way that they responded to the effects of the environment on vector competence. The effects of mosquito age on aspects of vector competence were dependent on the EIT and dose, and they changed depending on the colony. Complex interactions must be considered in laboratory studies of vector competence, because the extent of the genetic and environmental variation controlling vector competence in nature is largely unknown. Differences in the environmental (EIT and dose) and biological (mosquito age and colony) effects from previous studies of Cx. p. quinquefasciatus vector competence for St. Louis encephalitis virus are discussed.

  6. Host-Feeding Preference of the Mosquito, Culex quinquefasciatus, in Yucatan State, Mexico

    Science.gov (United States)

    Garcia-Rejon, Julian E.; Blitvich, Bradley J.; Farfan-Ale, Jose A.; Loroño-Pino, Maria A.; Chi Chim, Wilberth A.; Flores-Flores, Luis F.; Rosado-Paredes, Elsy; Baak-Baak, Carlos; Perez-Mutul, Jose; Suarez-Solis, Victor; Fernandez-Salas, Ildefonso; Beaty, Barry J.

    2010-01-01

    Studies were conducted to determine the host-feeding preference of Culex quinquefasciatus Say (Diptera: Culicidae) in relation to the availability of human and domestic animals in the city of Merida, Yucatan State, Mexico. Mosquitoes were collected in the backyards of houses using resting wooden boxes. Collections were made five times per week from January to December 2005. DNA was extracted from engorged females and tested by PCR using universal avian- and mammalian-specific primers. DNA extracted from avian-derived blood was further analyzed by PCR using primers that differentiate among the birds of three avian orders: Passeriformes, Columbiformes and Galliformes. PCR products obtained from mammalian-derived blood were subjected to restriction enzyme digestion to differentiate between human-, dog-, cat-, pig-, and horse-derived blood meals. Overall, 82% of engorged mosquitoes had fed on birds, and 18% had fed on mammals. The most frequent vertebrate hosts were Galliformes (47.1%), Passeriformes (23.8%), Columbiformes (11.2%) birds, and dogs (8.8%). The overall human blood index was 6.7%. The overall forage ratio for humans was 0.1, indicating that humans were not a preferred host for Cx. quinquefasciatus in Merida. PMID:20578953

  7. Larvicidal potential of Cyathea species against Culex quinquefasciatus

    Directory of Open Access Journals (Sweden)

    Johnson Marimuthu alias Antonysamy

    2017-05-01

    Full Text Available Resistance to insecticides has persuaded researchers to find new methods to control Culex quinquefasciatus proliferation. Plants may be a source of alternative agents for mosquito control due to ever-growing insecticide resistance in mosquito vectors and environmental imbalance caused by synthetic insecticides. The present study was intended to study the larvicidal activity of selected Cyathea species against the filarial vector Culex quinquefasciatus. Larvicidal potential of different extracts were evaluated and larval mortality were recorded. The larvae were more sensitive to ethanolic extracts of studied three Cyathea species when compared to other extracts. Acetone, chloroform and petroleum ether extracts were considered to be less effective. The LC50 values of different extracts ranged from 320.72 to 657.03 µg/ml. The results exhibited that the tested three Cyathea species showed concentration dependent potential larvicidal effects and also provide an indication of possible bioactive properties.

  8. Comparative insecticidal efficacy of a new pyrethroid, metofluthrin, against colonies of Asian Culex quinquefasciatus and Culex pipiens pallens

    OpenAIRE

    Argueta, Tamara Belzabel Obispo; Kawada, Hitoshi; Shimabukuro, Kozue; Kubota, Shunichi; Shono, Yoshinori; Tsushima, Kazunori; Takagi, Masahiro

    2004-01-01

    Comparative insecticidal efficacy of metofluthrin, a newly synthesized pyrethroid, and other pyrethroids against several colonies of Asian Culex quinquefas-ciatus (from Indonesia, Thailand, Vietnam and Malaysia) was evaluated by topical application. Metofluthrin was the most effective against the four colonies of Cx. quinquefasciatus. The LD50-based relative effective ratio of metofluthrin against d-allethrin was higher in Cx. quinquefasciatus (33.3 to 78.8) than in Cx. pipiens pallens (27.8)...

  9. Culex quinquefasciatus (Diptera: Culicidae) as a potential West Nile virus vector in Tucson, Arizona: Blood meal analysis indicates feeding on both humans and birds

    OpenAIRE

    Zinser, Margaret; Ramberg, Frank; Willott, Elizabeth

    2004-01-01

    Most reports from the United States suggest Culex quinquefasciatus mosquitoes feed minimally on humans. Given the abundance of C. quinquefasciatus in residential Tucson and parts of metropolitan Phoenix, and the arrival of West Nile virus to this area, discovering the blood meal hosts of the local population is important. Using a sandwich ELISA technique, the local C. quinquefasciatus were found to feed on both humans and birds. This suggests they should be considered potential West Nile viru...

  10. Laboratory evaluation of lactic acid on attraction of Culex spp. (Diptera: Culicidae).

    Science.gov (United States)

    Allan, Sandra A; Bernier, Ulrich R; Kline, Daniel L

    2010-12-01

    The role of lactic acid was evaluated for attraction of Culex nigripalpus, Culex quinquefasciatus, Culex tarsalis, and Aedes aegypti in the laboratory using a dual-port olfactometer. When lactic acid was combined with chicken odor, attraction was increased for Cx. quinquefasciatus compared to chicken odor alone but not for Cx. nigripalpus, Cx. tarsalis, and Ae. aegypti. Lactic acid combined with hand odor did not change attraction of Cx. tarsalis and Ae. aegypti but decreased attraction of Cx. nigripalpus and Cx. quinquefasciatus. The addition of lactic acid to CO(2) increased attraction of Ae. aegypti and Cx. quinquefasciatus but reduced attraction of Cx. nigripalpus and Cx. tarsalis. Use of commercial lactic acid baits with CO(2) resulted in a similar trend except for Cx. nigripalpus which showed no difference. A blend of lactic acid, acetone, and dimethyl disulfide was attractive to Ae. aegypti (63.4%) but elicited low responses by all Culex spp. (1.3-26.8%). Addition of the blend to CO(2) increased attraction of Ae. aegypti and Cx. quinquefasciatus but reduced attraction of Cx. nigripalpus and Cx. tarsalis. The mixture of compounds plus CO(2) was as attractive as a hand for Cx. quinquefasciatus, Cx. tarsalis, and Ae. aegypti. © 2010 The Society for Vector Ecology.

  11. Comparative Bio-Efficacy and Synergism of New Generation Polyfluorobenzyl and Conventional Pyrethroids Against Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Sarkar, Manas; Akulwad, Ambadas; Kshirsagar, Rajendra; Muthukrishnan, Siva

    2018-05-28

    Intensive exposure to insecticides has resulted in the evolution of insecticide resistance in the mosquitoes. We tested the bio-efficacy of two Culex quinquefasciatus Say (Diptera: Culicidae) laboratory strains differentially bio-responsive to pyrethroids to understand the comparative efficacy of different polyfluorobenzyle and conventional pyrethroid molecules and the role of piperonyl butoxide (PBO) in synergizing these molecules in increased tolerance of mosquitoes to these molecules. We have taken deltamethrin (α-cyano pyrethroid with phenoxybenzyl moiety); permethrin (phenoxybenzyl pyrethroid without an α-cyano group); transfluthrin, dimefluthrin, metofluthrin, and meperfluthrin (polyfluorinated benzyl compounds); and prallethrin (modified cyclopentadienone compound) for this study. We found higher bio-efficacy in dimefluthrin, metofluthrin, and meperfluthrin compared with transfluthrin against tested mosquito strains. We found that transfluthrin exhibited synergism with PBO, which supports the hypothesis that P450 enzymes could play a role in the detoxification process of transfluthrin, which was earlier not believed. However, other polyfluorobenzyl pyrethroids with a 4-(methoxymethyl) phenyl capping in the tetrafluorobenzyl ring (dimefluthrin, metofluthrin, and meperfluthrin) exhibit greater synergism with PBO compared with transfluthrin. Further study is required to understand the mechanism for higher synergistic ratios in polyfluorobenzyl pyrethroids with 4-(methoxymethyl) phenyl moiety and ascertain the possible involvement of novel mechanisms that may involve in developing resistance. This is the first report of comparative bio-efficacy of multiple polyfluorobenzyl pyrethroids and PBO synergism against mosquitoes.

  12. Culex quinquefasciatus (Diptera: Culicidae as a potential West Nile virus vector in Tucson, Arizona: Blood meal analysis indicates feeding on both humans and birds

    Directory of Open Access Journals (Sweden)

    Margaret Zinser

    2004-06-01

    Full Text Available Most reports from the United States suggest Culex quinquefasciatus mosquitoes feed minimally on humans. Given the abundance of C. quinquefasciatus in residential Tucson and parts of metropolitan Phoenix, and the arrival of West Nile virus to this area, discovering the blood meal hosts of the local population is important. Using a sandwich ELISA technique, the local C. quinquefasciatus were found to feed on both humans and birds. This suggests they should be considered potential West Nile virus vectors.

  13. Mosquito repellent properties of Delonix elata (L. gamble (Family: Fabaceae against filariasis vector, Culex quinquefasciatus Say. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Marimuthu Govindarajan

    2014-02-01

    Full Text Available Objective: To determine the repellent activity of hexane, ethyl acetate, benzene, chloroform and methanol extract of Delonix elata (D. elata leaf and seed against Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Evaluation was carried out in a net cage (45 cm伊30 cm伊25 cm containing 100 blood starved female mosquitoes of Cx. quinquefasciatus. Repellent activity was carried out in the laboratory conditions according to the WHO 2009 protocol. Plant crude extracts of D. elata were applied at 1.0, 2.5, and 5.0 mg/cm2 separately in the exposed fore arm of study subjects. Ethanol was used as the sole control. Results: In this study, the applied plant crude extracts were observed to protect against mosquito bites. There were no allergic reactions experienced by the study subjects. The repellent activity of the extract was dependent on the strength of the extract. Among the tested solvents, the leaf and seed methanol extract showed the maximum efficacy. The highest concentration of 5.0 mg/cm2 provided over 150 min and 120 min protection, respectively. Conclusions: Crude extracts of D. elata exhibit the potential for controlling Cx. quinquefasciatus, the mosquito vector of filariasis.

  14. Mosquito larvicidal and ovicidal properties of Pithecellobium dulce (Roxb. Benth. (Fabaceae against Culex quinquefasciatus Say (Diptera: Culicidae

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    Govindarajan Marimuthu

    2014-04-01

    Full Text Available Objective: To assess the larvicidal and ovicidal potential of the crude hexane, benzene, chloroform, ethyl acetate and methanol solvent extracts from the medicinal plant, Pithecellobium dulce (P. dulce against filariasis vector mosquito, Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Twenty five early third instar larvae of Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol of WHO (2005. The larval mortality was observed after 24 h of treatment. The ovicidal activity was determined against Cx. quinquefasciatus mosquito eggs to various concentrations ranging from 100-750 mg/L under the laboratory conditions. Results: The methanol extract of the leaves and seed of P. dulce was the most effective against the larvae with LC 50 and LC90 values 164.12 mg/L, 214.29 mg/L, 289.34 mg/L and 410.18 mg/L being observed after 24 h of exposure. The efficacy of methanol was followed by that of the ethyl acetate, chloroform, benzene and hexane extracts. The mean percent hatchability of the egg rafts were observed after 48 h of treatment. About 100% mortality was observed at 500 mg/L for leaf and 750 mg/L for seed methanol extracts of P. dulce. Conclusions: From the results, it can be concluded that the larvicidal and ovicidal effect of P. dulce against Cx. quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

  15. Susceptibilidade larval de populações de Aedes aegypti e Culex quinquefasciatus a inseticidas químicos Larval susceptibility of Aedes aegypti and Culex quinquefasciatus populations to chemical insecticides

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    Jairo Campos

    2003-08-01

    Full Text Available OBJETIVO: Avaliar a susceptibilidade a inseticidas químicos de larvas de Culex quinquefasciatus e Aedes aegypti, provenientes de áreas sujeitas ou não a tratamentos de controle. MÉTODOS: Foram coletadas larvas de mosquitos em uma área não sujeita a tratamentos com inseticidas (Campinas, SP e em áreas sujeitas a esses tratamentos (Campo Grande, MS e Cuiabá, MT. Foram usados bioensaios com concentrações diagnóstico e concentrações múltipla de inseticidas organofosforados e piretróides, segundo padrão da Organização Mundial de Saúde, para avaliar a susceptibilidade dessas larvas. RESULTADOS: Ensaios com larvas de Culex quinquefasciatus de Campinas, SP, permitiram a suspeita de resistência à cipermetrina e evidenciaram resistência à ciflutrina. Larvas dessa espécie coletadas em Campo Grande, MS, e Campinas, SP, apresentaram resistência ao temephos. Para a colônia campineira desta espécie, foram estabelecidas as razões de resistência: RR50=6,36 e RR95=4,94, com base em linhagem susceptível padrão. Adicionalmente, os testes com Aedes aegypti mostraram susceptibilidade similar ao temephos em uma população de campo (Cuiabá, MT e uma de laboratório. CONCLUSÕES: Os resultados indicam resistência a organofosforado e piretróides em Culex quinquefasciatus, evidenciando a necessidade de avaliações e monitoramento da efetividade dos inseticidas a serem usados nos programas de controle de mosquitos.OBJECTIVE: To evaluate the susceptibility to chemical insecticides of Culex quinquefasciatus and Aedes aegypt larvae from areas subjected to control treatments or not. METHODS: Bioassays for diagnostic concentration and multiple concentration were performed for organophosphate and pyrethroid insecticides according to World Health Organization parameters. The susceptibility was assessed for mosquito larvae collected from an area not subjected to chemical control (Campinas, State of São Paulo, SP and from other areas (Campo

  16. Avaliação da sensibilidade de adultos de Culex quinquefasciatus Say a inseticidas químicos de contato Evaluation of the sensitivity of the adult Culex quinquefasciatus Say to chemical insecticides

    Directory of Open Access Journals (Sweden)

    Carlos Fernando S. de Andrade

    1990-08-01

    Full Text Available A sensibilidade de adultos do pernilongo doméstico Culex quinquefasciatus a 5 inseticidas químicos foi avaliada sob condições de laboratório pelo critério de Tempo Letal Mediano (TL50. Foram utilizados o organofosforado Malathion e quatro piretróides: Bifenthrin, Deltamethrin, Esfenvalerate e Alfamethrin. Foi sugerida uma técnica simples e eficiente para se avaliar adultos de um dia de idade incluindo 5 repetições para cada tratamento. Os resultados obtidos mostraram ser o método bastante adequado para avaliações rotineiras. Não ocorreu resistência a esses 5 princípios ativos, na população natural de Culex quinquefasciatus estudada.The sensitivity of the adult house mosquito Culex quinquefasciatus to 5 chemical insecticides was evaluated under laboratory condictions, based on the Median Lethal Time (LT50 criterion. The organophosphorous Malathion and four pyrethroids: Bifenthrin, Deltamethrin, Esfenvalerate and Alfamethrin were utilized. An easy and efficient technique was suggested for the testing of one-day-old adults, including five repetitions for each treatment. The results revealed the full adequacy of this method for routine use. Further, no resistance to the 5 chemical compounds was detected among this natural population of Cx. quinquefasciatus.

  17. Ciclo de vida de Culex quinquefasciatus Say, 1826 (Diptera: Culicidae bajo condiciones no controladas en Bogotá.

    Directory of Open Access Journals (Sweden)

    Myriam Janeth Salazar

    2004-12-01

    Full Text Available El objetivo de este trabajo fue estudiar varios aspectos del crecimiento y el desarrollo de los estadios inmaduros de Culex quinquefasciatus Say, 1826 (Diptera: Culicidae, especie antropofílica frecuentemente encontrada en Bogotá. Con este fin, se realizaron dos experimentos en diferentes épocas del año 2001 (enero-febrero y septiembre-octubre, bajo condiciones no controladas (luz, temperatura y humedad relativa. Se colocaron recipientes plásticos transparentes con agua de charca a la que se le adicionó concentrado para perro; se tomaron cuatro balsas al azar para estudiar el ciclo de vida utilizando los parámetros de la tabla de vida: mortalidad y supervivencia. Las hembras ovipositaron entre cinco y ocho días después de la ingestión de sangre. El número de huevos por balsa varió entre 152 y 203. La eclosión de larvas L1 fue de 50% en el primer experimento y de 75% en el segundo. Se destacó la naturaleza no sincrónica de la eclosión de las L1, la menor duración proporcional del estadio de pupa (11% del tiempo del desarrollo total y la eficiencia del cambio pupa-adulto (98,61%. Se reporta una menor duración del ciclo de lo informado previamente. Además, los altos porcentajes de eclosión (83,58%, pupación (86,63% y emergencia (98,61% con las condiciones presentes para estos experimentos (temperatura media 14,8°C y 15,1°C y humedad relativa del 72,5% y 74,1%, respectivamente indican el alto grado de adaptación de C. quinquefasciatus al ambiente bogotano. Estas características, más la capacidad vectorial y la resistencia a los insecticidas, hacen de esta especie un problema de salud pública.

  18. Zika virus replication in the mosquito Culex quinquefasciatus in Brazil.

    Science.gov (United States)

    Guedes, Duschinka Rd; Paiva, Marcelo Hs; Donato, Mariana Ma; Barbosa, Priscilla P; Krokovsky, Larissa; Rocha, Sura W Dos S; Saraiva, Karina LA; Crespo, Mônica M; Rezende, Tatiana Mt; Wallau, Gabriel L; Barbosa, Rosângela Mr; Oliveira, Cláudia Mf; Melo-Santos, Maria Av; Pena, Lindomar; Cordeiro, Marli T; Franca, Rafael F de O; Oliveira, André Ls de; Peixoto, Christina A; Leal, Walter S; Ayres, Constância Fj

    2017-08-09

    Zika virus (ZIKV) is a flavivirus that has recently been associated with an increased incidence of neonatal microcephaly and other neurological disorders. The virus is primarily transmitted by mosquito bite, although other routes of infection have been implicated in some cases. The Aedes aegypti mosquito is considered to be the main vector to humans worldwide; however, there is evidence that other mosquito species, including Culex quinquefasciatus, transmit the virus. To test the potential of Cx. quinquefasciatus to transmit ZIKV, we experimentally compared the vector competence of laboratory-reared Ae. aegypti and Cx. quinquefasciatus. Interestingly, we were able to detect the presence of ZIKV in the midgut, salivary glands and saliva of artificially fed Cx. quinquefasciatus. In addition, we collected ZIKV-infected Cx. quinquefasciatus from urban areas with high microcephaly incidence in Recife, Brazil. Corroborating our experimental data from artificially fed mosquitoes, ZIKV was isolated from field-caught Cx. quinquefasciatus, and its genome was partially sequenced. Collectively, these findings indicate that there may be a wider range of ZIKV vectors than anticipated.

  19. Adulticidal activity of Pithecellobium dulce (Roxb.) Benth. against Culex quinquefasciatus (Say)

    OpenAIRE

    Govindarajan M; Sivakumar R; Rajeswary M; Yogalakshmi K

    2012-01-01

    Objective: To determine the adulticidal efficacy of different solvent leaf and seed extracts of Pithecellobium dulce (P. dulce) against Culex quinquefasciatus (Cx. quinquefasciatus). Methods: Sucrose-fed and blood starved mosquitoes were released into the tube, and the mortality effects of the extracts were observed every 10 min for 3 h exposure period. At the end of 1, 2, and 3 h exposure periods, the mosquitoes were placed in the holding tube. Cotton pads soaked in 10% sugar ...

  20. Immature Aedes mosquitoes colonize Culex quinquefasciatus breeding sites in neighborhoods in the municipality of Olinda, State of Pernambuco

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    Suzane Alves dos Santos

    2014-12-01

    Full Text Available Introduction The present study shows the colonization of Aedes mosquitoes in breeding sites specific for Culex quinquefasciatus in neighborhoods in the municipality of Olinda. Methods Samples were collected between May 2011 and June 2012 from breeding sites positive for Cx. quinquefasciatus by using a ladle and manual suction pump. Results Aedes aegypti (0.12%, Aedes albopictus (0.03%, and Cx. quinquefasciatus (99.8% were found across the breeding sites. Conclusions The presence of Aedes ssp. in several Cx. quinquefasciatus breeding sites with a heavy load of organic material demonstrates the need to review the concepts and methods used for treatment, as the use of specific larvicide for breeding sites of Culex.

  1. Larvicidal activity of the methanol extract and fractions of the green fruits of Solanum lycocarpum (Solanaceae against the vector Culex quinquefasciatus (Diptera: Culicidae

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    Thamer Matias Pereira

    2014-10-01

    Full Text Available Introduction The larvicidal activity of Solanum lycocarpum against Culex quinquefasciatus is unknown. Methods We evaluated the larvicidal activity of extracts of the green fruits of Solanum lycocarpum against third and fourth instar larvae of C. quinquefasciatus. Results Dichloromethane and ethyl acetate fractions showed the greatest larvicidal effect at 200mg/L (83.3% and 86.7%, respectively. The methanol and dichloromethane, ethyl acetate, and hydromethanolic fractions demonstrated larvicidal effects against C. quinquefasciatus, with LC50 values of 126.24, 75.13, 83.15, and 207.05mg/L, respectively. Conclusions Thus, when considering new drugs with larvicidal activity from natural products, S. lycocarpum fruits may be good candidate sources.

  2. Associative learning of odor with food- or blood-meal by Culex quinquefasciatus Say (Diptera: Culicidae)

    Science.gov (United States)

    Tomberlin, Jeffery K.; Rains, Glen C.; Allan, Sandy A.; Sanford, Michelle R.; Lewis, W. Joe

    2006-11-01

    The ability of many insects to learn has been documented. However, a limited number of studies examining associative learning in medically important arthropods has been published. Investigations into the associative learning capabilities of Culex quinquefasciatus Say were conducted by adapting methods commonly used in experiments involving Hymenoptera. Male and female mosquitoes were able to learn a conditioned stimulus that consisted of an odor not normally encountered in nature (synthetic strawberry or vanilla extracts) in association with an unconditioned stimulus consisting of either a sugar (males and females) or blood (females) meal. Such information could lead to a better understanding of the ability of mosquitoes to locate and select host and food resources in nature.

  3. Isolation and characterization of halotolerant bacteria associated with the midgut of Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Reegan, Appadurai Daniel; Paulraj, Michael Gabriel; Ignacimuthu, Savarimuthu

    2013-11-01

    We show for the first time that the midgut of Culex quinquefasciatus (Say) mosquito larvae harbors halotolerant bacteria. The midgut from field collected Cx. quinquefasciatus larvae were dissected under aseptic conditions, homogenized and plated on LB agar medium with 2% (w/v) NaCl. Two different colonies were successfully isolated and bacterial isolates were identified by 16S rRNA sequences. The halotolerant bacterial isolates were: Halobacillus litoralis (CxH1) and Staphylococcus cohnii (CxH2). The gene sequence of these isolates has been deposited in GenBank (JN016804 and JN183986). These halotolerant bacteria grew in the absence of salt (0%) as well as in the presence of relatively high salt concentrations in culture medium (20%), and grew best in the presence of 8-10% (w/v) NaCl. H. litoralis and S. cohnii showed growth up to 18 and 20% (w/v) NaCl, respectively. Optimum growth temperatures for both the bacteria were between 30-37 degrees C. H. litoralis was resistant to the antibiotics oxacillin, penicillin, polymixin and S. cohnii was resistant to the antibiotic oxacillin.

  4. DAYA LARVASIDA EKSTRAK BIJI SRIKAYA (ANNONA SQUAMOSA DENGAN RENTANG WAKTU PENYIMPANAN YANG BERBEDA TERHADAP LARVA CULEX QUINQUEFASCIATUS

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    Wisnu Satria A.K.

    2013-03-01

    Full Text Available Abstract. Synthetic insecticide have been used to control Culex quinquefasciatus, but the prolonged usage of synthetic insecticide has a bad impact on the environment and may caused resistance. Sugar apple’s (Annona squamosa seeds which contain alkaloid can be used as an alternative insecticide that was safe for environment. This research aims is to know the effect of sugar apple’s seeds with different length of storage as C. quinquefasciatus larvacide. This research was an experimental study with a randomized controlled trial group design approach. The test material was an extract of sugar apple’s seeds which have been kept for 0, 1, 2, and 3 week with LC50 (0,47 ppm was used. Each treatment used 25 C. quinquefasciatus larvae from third instar larvae stage and replicated five times. After exposed for 24 hours, dead larvae counted. The result confirmed that the extract of sugar apple’s seeds which has been stored in 0, 1, 2, and 3 week did not showed any significant different on larvae mortality. Extract of sugar apple’s seeds which have been stored in 0, 1, 2, and 3 week have an equal activity as Culex quinquefasciatus larvicide. Key Word: Sugar apple (Annona squamosa, seeds, larvicide, Culex quinquefasciatus, length of storage Abstrak. Insektisida sintetik telah banyak digunakan untuk mengontrol Culex quinquefasciatus, tetapi penggunaan insektisida sintetik terus-menerus berdampak buruk terhadap lingkungan dan mengakibatkan resistensi. Fakta ini menjadi alasan biji srikaya (Annona squamosa yang mengandung alkaloid digunakan sebagai insektisida alternatif yang aman bagi lingkungan. Penelitian ini bertujuan untuk mengetahui pengaruh biji srikaya dengan perbedaan lama penyimpanan terhadap larva C. quinquefasciatus. Penelitian ini merupakan penelitian eksperimental dengan desain rancangan acak kelompok. Bahan uji adalah ekstrak biji srikaya yang telah disimpan selama 0, 1, 2, dan 3 minggu. Sampel penelitian ini adalah larva instar ketiga

  5. Toxicity of Boswellia dalzielii (Burseraceae) Leaf Fractions Against Immature Stages of Anopheles gambiae (Giles) and Culex quinquefasciatus (Say) (Diptera: Culicidae)

    Science.gov (United States)

    Younoussa, Lame; Nukenine, Elias Nchiwan; Esimone, Charles Okechukwu

    2016-01-01

    Mosquitoes are vectors of several human pathogens, and great attention has recently been placed on insecticides from plant-derived products, in search for mosquito control agents. This study, thus, investigated the potency of Boswellia dalzielii methanol leaf extract and its four fractions as mosquito ovicide, larvicide, and pupicide against Anopheles gambiae and Culex quinquefasciatus. The plant products were tested at the following concentrations: 125, 250, 500, 1000, and 2000 ppm on eggs and 312.5, 625, 1250, and 2500 ppm on the larvae and pupae of the mosquitoes. For results, hatchability of A. gambiae eggs was reduced to 5% with n-hexane fraction at 2000 ppm. Among the plant products tested, n-hexane fraction was most toxic against A. gambiae (LC50 = 385.9 ppm) and C. quinquefasciatus (LC50 = 3394.9 ppm). The n-hexane fraction of B. dalzielii might be used as a mosquitocidal agent in the breeding sites of A. gambiae and C. quinquefasciatus. PMID:27279752

  6. Synthesis of eco-friendly silver nanoparticles from Morinda tinctoria leaf extract and its larvicidal activity against Culex quinquefasciatus.

    Science.gov (United States)

    Kumar, K Ramesh; Nattuthurai, N; Gopinath, Ponraj; Mariappan, Tirupathi

    2015-02-01

    Mosquitoes are the major vector for the transmission of malaria, dengue fever, yellow fever, filariasis, chikungunya and Japanese encephalitis, and they accounted for global mortality and morbidity with increased resistance to common insecticides. The aim of this study was to investigate the larvicidal potential of the acetone leaf extracts of Morinda tinctoria and synthesized silver nanoparticles against third instar larvae of Culex quinquefasciatus Say (Diptera: Culicidae). Nanoparticles are being used in many commercial applications. It was found that aqueous silver ions can be reduced by aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. Synthesized AgNPs were characterized by ultraviolet-visible (UV-vis) spectroscopy, Atomic force microscopy (AFM) and Fourier transform infrared spectroscopy (FT-IR) analysis. The synthesized silver nanoparticles have also been tested against the third instar larvae of C. quinquefasciatus. The leaf extract and the AgNPs high mortality values were 50 % lethal concentration (LC50) = 8.088 and 1.442 ppm against C. quinquefasciatus, respectively. The results recorded from ultraviolet-visible spectroscopy, atomic force microscopy and Fourier transform infrared spectroscopy support the biosynthesis and characterization of silver nanoparticles. These results suggest that the leaf extract of M. tinctoria and synthesis of AgNPs have the potential to be used as an ideal eco-friendly approach for the control of C. quinquefasciatus. By this approach, it is suggestive that this rapid synthesis of nanoparticles would be proper for developing a biological process for mosquito control.

  7. Acute and chronic activity of perchlorate and hexavalent chromium contamination on the survival and development of Culex quinquefasciatus Say (Diptera: Culicidae)

    International Nuclear Information System (INIS)

    Sorensen, Mary A.; Jensen, Peter D.; Walton, William E.; Trumble, John T.

    2006-01-01

    Effects of water contamination with perchlorate and hexavalent chromium [Cr (VI)] on the mosquito Culex quinquefasciatus were assessed. The chronic (10-day) LC 5 s values for perchlorate and chromium were 74 ± 8.0 mg/L and 0.41 ± 0.15 mg/L, respectively. Relative Growth Index, a measure of growth and mortality rates in a population, was significantly reduced within 5 days for levels of perchlorate as low as 25 mg/L and for levels of chromium as low as 0.16 mg/L. Neither compound altered wing length of surviving adults. In combination, contaminants were synergistic, causing 14% more mortality than predicted. Acute (24-h) LC 5 values for perchlorate and Cr (VI) were 17,000 ± 3200 and 38 ± 1.3 mg/L, respectively. Effects on mosquito larvae in contaminated environments are likely to be observed for Cr (VI) but not for perchlorate, which generally does not occur at levels as high as those shown here to affect larval mosquitoes. - While pollution with hexavalent chromium may adversely affect Culex quinquefasciatus larvae, levels of perchlorate currently in the environment will not impact these insects

  8. Acute and chronic activity of perchlorate and hexavalent chromium contamination on the survival and development of Culex quinquefasciatus Say (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Sorensen, Mary A. [Department of Entomology, University of California, Riverside, CA 92521 (United States)]. E-mail: mary.sorensen@email.ucr.edu; Jensen, Peter D. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Walton, William E. [Department of Entomology, University of California, Riverside, CA 92521 (United States); Trumble, John T. [Department of Entomology, University of California, Riverside, CA 92521 (United States)

    2006-12-15

    Effects of water contamination with perchlorate and hexavalent chromium [Cr (VI)] on the mosquito Culex quinquefasciatus were assessed. The chronic (10-day) LC{sub 5}s values for perchlorate and chromium were 74 {+-} 8.0 mg/L and 0.41 {+-} 0.15 mg/L, respectively. Relative Growth Index, a measure of growth and mortality rates in a population, was significantly reduced within 5 days for levels of perchlorate as low as 25 mg/L and for levels of chromium as low as 0.16 mg/L. Neither compound altered wing length of surviving adults. In combination, contaminants were synergistic, causing 14% more mortality than predicted. Acute (24-h) LC{sub 5} values for perchlorate and Cr (VI) were 17,000 {+-} 3200 and 38 {+-} 1.3 mg/L, respectively. Effects on mosquito larvae in contaminated environments are likely to be observed for Cr (VI) but not for perchlorate, which generally does not occur at levels as high as those shown here to affect larval mosquitoes. - While pollution with hexavalent chromium may adversely affect Culex quinquefasciatus larvae, levels of perchlorate currently in the environment will not impact these insects.

  9. Genetic Diversity and Population Genetics of Mosquitoes (Diptera: Culicidae: Culex spp. from the Sonoran Desert of North America

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    Edward Pfeiler

    2013-01-01

    Full Text Available The population genetics and phylogenetic relationships of Culex mosquitoes inhabiting the Sonoran Desert region of North America were studied using mitochondrial DNA and microsatellite molecular markers. Phylogenetic analyses of mitochondrial cytochrome c oxidase subunit I (COI from mosquitoes collected over a wide geographic area, including the Baja California peninsula, and mainland localities in southern Arizona, USA and Sonora, Mexico, showed several well-supported partitions corresponding to Cx. quinquefasciatus, Cx. tarsalis, and two unidentified species, Culex sp. 1 and sp. 2. Culex quinquefasciatus was found at all localities and was the most abundant species collected. Culex tarsalis was collected only at Tucson, Arizona and Guaymas, Sonora. The two unidentified species of Culex were most abundant at Navojoa in southern Sonora. Haplotype and nucleotide diversities in the COI gene segment were substantially lower in Cx. quinquefasciatus compared with the other three species. Analysis of molecular variance revealed little structure among seven populations of Cx. quinquefasciatus, whereas significant structure was found between the two populations of Cx. tarsalis. Evidence for an historical population expansion beginning in the Pleistocene was found for Cx. tarsalis. Possible explanations for the large differences in genetic diversity between Cx. quinquefasciatus and the other species of Culex are presented.

  10. Genetic Diversity and Population Genetics of Mosquitoes (Diptera: Culicidae: Culex spp.) from the Sonoran Desert of North America

    Science.gov (United States)

    Pfeiler, Edward; Flores-López, Carlos A.; Mada-Vélez, Jesús Gerardo; Escalante-Verdugo, Juan; Markow, Therese A.

    2013-01-01

    The population genetics and phylogenetic relationships of Culex mosquitoes inhabiting the Sonoran Desert region of North America were studied using mitochondrial DNA and microsatellite molecular markers. Phylogenetic analyses of mitochondrial cytochrome c oxidase subunit I (COI) from mosquitoes collected over a wide geographic area, including the Baja California peninsula, and mainland localities in southern Arizona, USA and Sonora, Mexico, showed several well-supported partitions corresponding to Cx. quinquefasciatus, Cx. tarsalis, and two unidentified species, Culex sp. 1 and sp. 2. Culex quinquefasciatus was found at all localities and was the most abundant species collected. Culex tarsalis was collected only at Tucson, Arizona and Guaymas, Sonora. The two unidentified species of Culex were most abundant at Navojoa in southern Sonora. Haplotype and nucleotide diversities in the COI gene segment were substantially lower in Cx. quinquefasciatus compared with the other three species. Analysis of molecular variance revealed little structure among seven populations of Cx. quinquefasciatus, whereas significant structure was found between the two populations of Cx. tarsalis. Evidence for an historical population expansion beginning in the Pleistocene was found for Cx. tarsalis. Possible explanations for the large differences in genetic diversity between Cx. quinquefasciatus and the other species of Culex are presented. PMID:24302868

  11. Larval Habitat Substrates Could Affect the Biology and Vectorial Capacity of Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Shah, Rizwan Mustafa; Ali, Qasim; Alam, Mehboob; Shad, Sarfraz Ali; Majeed, Shahid; Riaz, Muhammad; Binyameen, Muhammad

    2017-05-01

    Culex quinquefasciatus Say is an important disease vector throughout much of the world. Experiments were conducted to determine the effects of different larval habitat substrates on the fitness and biting efficiency of Cx. quinquefasciatus adults. Our findings indicate that the development time (egg to adult) of larvae reared in irrigation water was 8.63 d while that of larvae reared in distilled water was 17.10 d (Effect size = 0.95). However, the rate of adult emergence was similar for all the tested treatments. Furthermore, the mean weight of an egg raft varied between larval habitats: distilled water (1.83 mg), rainfall water (1.25 mg), irrigation water (1.52 mg), and sewerage water (2.52 mg) (Effect size = 0.91). But, the fecundity (eggs per female) and hatchability (%) were statistically similar in all the rearing mediums (Effect size = 0.79). Longevity of females in all the tested populations did not differ significantly (Effect size = 0.91). The mean relative growth rates of larvae reared in tap water (0.80) and distilled water (0.86) habitats were lower than growth rates in all other rearing habitats (Effect size = 0.96). The intrinsic rate of natural increase in tap water (0.27) and irrigation water (0.35) was significantly higher than that in distilled water (0.09) and sewerage water (0.16) (Effect size = 0.84). Adults reared in rain water had the highest biting efficiency among all the tested populations. These results provide useful information for the management of Cx. quinquefasciatus. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Effects of an aqueous extract of Azadirachta indica on the groCulex ...

    African Journals Online (AJOL)

    The neem tree Azadirachta indica Juss (Meliaceae) is one of the most studied plant species for pest control, including mosquitoes. However, the effect of aqueous neem seed extracts (ANSE) on each of the 4 instars of mosquito Culex quinquefasciatus Say (Diptera: Culicidae) is unknown. In order to determine the effect of ...

  13. Abrigos de mosquitos Culex (Culex em zona rural (Diptera: Culicidae Resting places of mosquitoes Culex (Culex in rural zones (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Almério de Castro Gomes

    1990-10-01

    Full Text Available As atividades antrópicas levadas a cabo em zona rural têm afetado o comportamento de mosquitos Culex (Culex, motivo pelo qual foi realizada investigação para observar seus abrigos naturais em área de pastagem, margem e interior de matas primitivas ou residuais. Foram escolhidas três localidades com características mesológicas diferenciadas pelo tipo de atividade humana, todas situadas na região do Vale do Ribeira, Estado de São Paulo, Brasil. As espécies mais abundantes foram Cx. mollis (28,0%, Cx. declarator (25,0%, Cx. lygrus (13,0% e Cx. coronator (9,6%. O conjunto Cx. Bidens + Cx. dolosus + Cx. chidesteri, de hábito mais urbanizado, foi capturado em número muito reduzido. Com relação aos ambientes pesquisados, a mata contribuiu com 2.281 indivíduos (71,4%, sugerindo ser local de abrigo preferido pelo grupo, exceto para Cx. quinquefasciatus. Avaliou-se o potencial de domiciliação de cada espécie e suas conseqüências para a população humana.The human activities carried out in rural zones have been affeecting the behavior of mosquitoes of the Culex (Culex subgenera, which was the reason for undertaking this investigation with a view to registering data on the natural resting places in pastures and on the edge of or within primitive and residual forest areas. Three localities with different mesological conditions, as to type of human activity, all them situated in the Ribeira Valley region of S. Paulo State, Brazil, were chosen. The species most abundantly found were Cx. mollis (28.0%, Cx. declarator (25.0%, Cx. lygrus (13.0% and Cx. coronator (9.6%. The collection of mosquitoes Cx. bidens + Cx. dolosus + Cx. chidesteri, known to be more urban, was much smaller than that of any other species of the group. With reference to outdoor environments, woodland contributed with 2,281 individuals (71.4% suggesting their preference for this resting place, except for Cx. quinquefasciatus. Results are evaluated for the determination

  14. Comparative efficacy and pathogenicity of keratinophilic soil fungi against Culex quinquefasciatus larvae.

    Science.gov (United States)

    Mohanty, Suman Sundar; Prakash, Soam

    2010-09-01

    Out of seven fungal species belonging to four genera isolated from pond and wallow soils using feathers of Pavo cristatus as bait, four species viz., Aspergillus flavus, Aspergillus niger, Chrysosporium pseudomerdarium and Trichophyton ajelloi were most frequent. Chrysosporium and Trichophyton spp. were more pathogenic on Culex quinquefasciatus larvae than Aspergillus and Penicillium. The bioefficacy tests conducted as per the protocol of World Health Organization and the LC(50) values calculated by the Probit analysis showed that 3(rd)-instar C. quinquefasciatus were more susceptible to the conidia of above fungi. Highest mortality was observed in the larvae of C. quinquefasciatus when exposed to T. ajelloi. The density of fungal conidia was greatest on the ventral brush, palmate hair and anal region of the mosquito larvae after exposing for 72 hours. The potentiality of these fungi for use in the control of C. quinquefasciatus is discussed which can be exploited as a suitable biocontrol agent in the tropics.

  15. Evaluation of Two Entomopathogenic Fungi for Control of Culex quinquefasciatus (Diptera: Culicidae) in Underground Storm Drains in the Coachella Valley, California, United States.

    Science.gov (United States)

    Popko, David A; Henke, Jennifer A; Mullens, Bradley A; Walton, William E

    2017-12-22

    Commercially available formulations of two entomopathogenic fungi, Beauveria bassiana (Bals.-Criv.) Vuill. (Hypocreales: Clavicipitaceae) and Metarhizium anisopliae (Metchnikoff) Sorokin (Hypocreales: Clavicipitaceae), were assessed for control of Culex quinquefasciatus Say (Diptera: Culicidae) in underground storm drain systems (USDS) in the Coachella Valley of southern California. Each of three treatments, the two fungi or a water control, was applied to 1 m2 of vertical wall at eight USDS sites in spring and autumn of 2015. Fungal infectivity and lethality were assessed at 1 d and 1, 2, and 4 wk post-application. Overnight bioassays using adult lab-reared female mosquitoes were carried out on the treated USDS wall areas and then mosquitoes were held in the laboratory for up to 21 d to allow fungal infections to be expressed. Postmortem fungal sporulation was assessed up to 2 wk at 100% humidity. Mosquito-fungal interactions also were assessed in bioassays of the three treatments on filter paper exposed to USDS conditions during autumn. Metarhizium anisopliae killed mosquitoes faster than B. bassiana; nevertheless, both freshly applied formulations caused greater than 80% mortality. Fungal persistence declined significantly after 1 wk under USDS conditions, but some infectivity persisted for more than 4 wk. Beauveria bassiana was more effective against Cx. qinquefasciatus in the spring, while M. anisopliae was more effective in the cooler conditions during autumn. USDS environmental conditions (e.g., temperature, relative humidity, standing water) influenced fungal-related mortality and infection of Cx. quinquefasciatus. The utility of these fungal formulations for mosquito abatement in the Coachella Valley and implications for fungal control agents in USDS environments are discussed. © The Author(s) 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  16. Mosquito larvicidal properties of silver nanoparticles synthesized using Heliotropium indicum (Boraginaceae) against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

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

    2014-06-01

    Mosquitoes transmit dreadful diseases to human beings wherein biological control of these vectors using plant-derived molecules would be an alternative to reduce mosquito population. In the present study activity of aqueous leaf extract and silver nanoparticles (AgNPs) synthesized using Helitropium indicum plant leaves against late third instar larvae of Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus. The range of varying concentrations of synthesized AgNPs (8, 16, 24, 32, and 40 μg/mL) and aqueous leaf extract (30, 60, 90, 120, and 150 μg/mL) were tested against the larvae of Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The synthesized AgNPs from H. indicum were highly toxic than crude leaf aqueous extract in three important vector mosquito species. The results were recorded from UV-Vis spectrum, Fourier transform infrared spectroscopy, scanning electron microscopy, energy-dispersive X-ray spectroscopy analysis, transmission electron microscopy, and histogram. The synthesized AgNPs showed larvicidal effects after 24 h of exposure. Considerable mortality was evident after the treatment of H. indicum for all three important vector mosquitoes. The LC50 and LC90 values of H. indicum aqueous leaf extract appeared to be effective against A. stephensi (LC50, 68.73 μg/mL; LC90, 121.07 μg/mL) followed by A. aegypti (LC50, 72.72 μg/mL; LC90, 126.86 μg/mL) and C. quinquefasciatus (LC50, 78.74 μg/mL; LC90, 134.39 μg/mL). Synthesized AgNPs against the vector mosquitoes of A. stephensi, A. aegypti, and C. quinquefasciatus had the following LC50 and LC90 values: A. stephensi had LC50 and LC90 values of 18.40 and 32.45 μg/mL, A. aegypti had LC50 and LC90 values of 20.10 and 35.97 μg/mL, and C. quinquefasciatus had LC50 and LC90 values of 21.84 and 38.10 μg/mL. No mortality was observed in the control. These results suggest that the leaf aqueous extracts of H. indicum and green synthesis of silver nanoparticles have the

  17. Larvicidal activity of oils, fatty acids, and methyl esters from ripe and unripe fruit of Solanum lycocarpum (Solanaceae against the vector Culex quinquefasciatus (Diptera: Culicidae

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    Viviane de Cássia Bicalho Silva

    2015-10-01

    Full Text Available ABSTRACTINTRODUCTION:The larvicidal activity of oils, fatty acids, and methyl esters of Solanum lycocarpum fruit against Culex quinquefasciatus is unknown.METHODS:The larvicidal activity of samples of ripe and unripe fruit from S. lycocarpum was evaluated against third and fourth instar larvae of C. quinquefasciatus .RESULTS:The oils, fatty acids, and methyl esters of S. lycocarpum showed the greatest larvicidal effect (57.1-95.0% at a concentration of 100mg/L (LC 50values between 0.70 and 27.54mg/L.CONCLUSIONS:Solanum lycocarpum fruit may be a good source of new natural products with larvicidal activity.

  18. Effects of heavy metals on population growth and metallothionein gene expression in the mosquito Culex quinquefasciatus, from Calcutta, India

    International Nuclear Information System (INIS)

    Sarkar, Sagartirtha; Duttagupta, Asish K.; Mal, Tarun K.

    2004-01-01

    Major water bodies in and around the city of Calcutta (India) receive heavy metal contaminated effluents from industries, households, and vehicular traffic through sewage or drainage. We quantified concentrations of Cu, Zn, and Cd from three water bodies at Kalighat, Tangra, and VIP Road, respectively. The concentrations of these heavy metals were significantly greater in the summer than in monsoon when heavy downpours resulted in reduced metal concentrations. Concentrations of metals in the mosquito Culex quinquefasciatus also reflected such seasonal fluctuations. Hatchability and survivorship of C. quinquefasciatus significantly differed among the sites and were reduced significantly from the control. Exposure to heavy metals also induced MT-gene expression in C. quinquefasciatus, likely helping them to survive in the water bodies stressed with heavy metals. MT-gene activity demonstrated significant variation among sites and seasons with the highest activity in the summer in the VIP Road population. This study suggests that C. quinquefasciatus could be used as an ecological indicator of heavy metal pollution by monitoring its MT-gene expression. - The mosquito, Culex quinquefasciatus, might be useful as an indicator of trace metals

  19. Effects of heavy metals on population growth and metallothionein gene expression in the mosquito Culex quinquefasciatus, from Calcutta, India

    Energy Technology Data Exchange (ETDEWEB)

    Sarkar, Sagartirtha; Duttagupta, Asish K.; Mal, Tarun K

    2004-01-01

    Major water bodies in and around the city of Calcutta (India) receive heavy metal contaminated effluents from industries, households, and vehicular traffic through sewage or drainage. We quantified concentrations of Cu, Zn, and Cd from three water bodies at Kalighat, Tangra, and VIP Road, respectively. The concentrations of these heavy metals were significantly greater in the summer than in monsoon when heavy downpours resulted in reduced metal concentrations. Concentrations of metals in the mosquito Culex quinquefasciatus also reflected such seasonal fluctuations. Hatchability and survivorship of C. quinquefasciatus significantly differed among the sites and were reduced significantly from the control. Exposure to heavy metals also induced MT-gene expression in C. quinquefasciatus, likely helping them to survive in the water bodies stressed with heavy metals. MT-gene activity demonstrated significant variation among sites and seasons with the highest activity in the summer in the VIP Road population. This study suggests that C. quinquefasciatus could be used as an ecological indicator of heavy metal pollution by monitoring its MT-gene expression. - The mosquito, Culex quinquefasciatus, might be useful as an indicator of trace metals.

  20. An impossible journey? The development of Plasmodium falciparum NF54 in Culex quinquefasciatus.

    Directory of Open Access Journals (Sweden)

    Julia Knöckel

    Full Text Available Although Anopheles mosquitoes are the vectors for human Plasmodium spp., there are also other mosquito species-among them culicines (Culex spp., Aedes spp.-present in malaria-endemic areas. Culicine mosquitoes transmit arboviruses and filarial worms to humans and are vectors for avian Plasmodium spp., but have never been observed to transmit human Plasmodium spp. When ingested by a culicine mosquito, parasites could either face an environment that does not allow development due to biologic incompatibility or be actively killed by the mosquito's immune system. In the latter case, the molecular mechanism of killing must be sufficiently powerful that Plasmodium is not able to overcome it. To investigate how human malaria parasites develop in culicine mosquitoes, we infected Culex quinquefasciatus with Plasmodium falciparum NF54 and monitored development of parasites in the blood bolus and midgut epithelium at different time points. Our results reveal that ookinetes develop in the midgut lumen of C. quinquefasciatus in slightly lower numbers than in Anopheles gambiae G3. After 30 hours, parasites have invaded the midgut and can be observed on the basal side of the midgut epithelium by confocal and transmission electron microscopy. Very few of the parasites in C. quinquefasciatus are alive, most of them are lysed. Eight days after the mosquito's blood meal, no oocysts can be found in C. quinquefasciatus. Our results suggest that the mosquito immune system could be involved in parasite killing early in development after ookinetes have crossed the midgut epithelium and come in contact with the mosquito hemolymph.

  1. Pengaruh Pengasapan (Thermal Fogging Insektisida Piretroid (Malation 95% Terhadap Nyamuk Aedes aegypti dan Culex quinquefasciatus di Pemukiman

    Directory of Open Access Journals (Sweden)

    Hasan Boesri

    2013-02-01

    Full Text Available Abstracts. The evaluation of piretroid insecticide (active ingredient Malation 95% was con­ducted in Sub district Tengarang, Semarang Segency, Central Java Province. The insecti­cide was applied using thermal fogging method for dosages of 125, 250, 375, 500 and 625 ml/ha (diluted in diesel to 10 litters. The evaluation of the efficacy was conducted against two mosquito species, Aedes aegypti (the main dengue haemorrhagic fever and Culex quinquefasciatus (the urban lymphatic fil­ariasis vector. Result of the evaluation was revealed that dosages of 500 and 625 ml/ha were effective against both tested mosquito species indoor and outdoor.Key Word: Aedes aegypti, Culex quinquefasciatus, insecticide Piretroid (Malation 95%, thermal fogging.

  2. A MIDGUT DIGESTIVE PHOSPHOLIPASE A2 IN LARVAL MOSQUITOES, AEDES ALBOPICTUS AND CULEX QUINQUEFASCIATUS

    Science.gov (United States)

    Phospholipase A2 (PLA2) is a secretory digestive enzyme that hydrolyzes ester bond at sn-2 position of dietary phospholipids, creating free fatty acid and lysophopholipid. The free fatty acids (arachidonic acid) are absorbed into midgut cells. Aedes albopictus and Culex quinquefasciatus digestive PL...

  3. Control of pyrethroid-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes with chlorfenapyr in Benin

    NARCIS (Netherlands)

    N'Guessan, R.; Boko, P.; Odjo, A.; Knols, B.G.J.; Akogbeto, M.; Rowland, M.

    2009-01-01

    Objective To compare the efficacy of chlorfenapyr applied on mosquito nets and as an indoor residual spray against populations of Anopheles gambiae and Culex quinquefasciatus in an area of Benin that shows problematic levels of pyrethroid resistance. Method Eight-week trial conducted in experimental

  4. Repellent activity of herbal essential oils against Aedes aegypti (Linn. and Culex quinquefasciatus (Say.

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    Duangkamon Sritabutra

    2013-08-01

    Full Text Available Objective: To determine the mosquito repellent activity of herbal essential oils against female Aedes aegypti and Culex quinquefasciatus. Methods: On a volunteer’s forearm, 0.1 mL of each essential oil was applied to 3 cm伊10 cm of exposed skin. The protection time was recorded for 3 min after every 30 min. Results: Essential oil from clove oil in olive oil and in coconut oil gave the longest lasting period of 76.50 min and 96.00 min respectively against Aedes aegypti. The citronella grass oil in olive oil, citronella grass oil in coconut oil and lemongrass oil in coconut oil exhibited protection against Culex quinquefasciatus at 165.00, 105.00, and 112.50 min respectively. Conclusions: The results clearly indicated that clove, citronella and lemongrass oil were the most promising for repellency against mosquito species. These oils could be used to develop a new formulation to control mosquitoes.

  5. Culex quinquefasciatus from Rio de Janeiro Is Not Competent to Transmit the Local Zika Virus.

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    Rosilainy Surubi Fernandes

    2016-09-01

    Full Text Available The Americas have suffered a dramatic epidemic of Zika since May in 2015, when Zika virus (ZIKV was first detected in Brazil. Mosquitoes belonging to subgenus Stegomyia of Aedes, particularly Aedes aegypti, are considered the primary vectors of ZIKV. However, the rapid spread of the virus across the continent raised several concerns about the transmission dynamics, especially about potential mosquito vectors. The purpose of this work was to assess the vector competence of the house mosquito Culex quinquefasciatus from an epidemic Zika area, Rio de Janeiro, Brazil, for local circulating ZIKV isolates.Culex quinquefasciatus and Ae. aegypti (positive control of ZIKV infection from Rio de Janeiro were orally exposed to two ZIKV strains isolated from human cases from Rio de Janeiro (Rio-U1 and Rio-S1. Fully engorged mosquitoes were held in incubators at 26 ± 1°C, 12 h:12 h light:dark cycle and 70 ± 10% humidity. For each combination mosquito population-ZIKV strain, 30 specimens were examined for infection, dissemination and transmission rates, at 7, 14 and 21 days after virus exposure by analyzing body (thorax plus abdomen, head and saliva respectively. Infection rates were minimal to completely absent in all Cx. quinquefasciatus-virus combinations and were significantly high for Ae. aegypti. Moreover, dissemination and transmission were not detected in any Cx. quinquefasciatus mosquitoes whatever the incubation period and the ZIKV isolate. In contrast, Ae. aegypti ensured high viral dissemination and moderate to very high transmission.The southern house mosquito Cx. quinquefasciatus from Rio de Janeiro was not competent to transmit local strains of ZIKV. Thus, there is no experimental evidence that Cx. quinquefasciatus likely plays a role in the ZIKV transmission. Consequently, at least in Rio, mosquito control to reduce ZIKV transmission should remain focused on Ae. aegypti.

  6. Adulticidal activity of Pithecellobium dulce (Roxb. Benth. against Culex quinquefasciatus (Say

    Directory of Open Access Journals (Sweden)

    Govindarajan M

    2012-04-01

    Full Text Available Objective: To determine the adulticidal efficacy of different solvent leaf and seed extracts of Pithecellobium dulce (P. dulce against Culex quinquefasciatus (Cx. quinquefasciatus. Methods: Sucrose-fed and blood starved mosquitoes were released into the tube, and the mortality effects of the extracts were observed every 10 min for 3 h exposure period. At the end of 1, 2, and 3 h exposure periods, the mosquitoes were placed in the holding tube. Cotton pads soaked in 10% sugar solution with vitamin B complex were placed in the tube during the holding period of 24 h. Mortality of the mosquitoes was recorded after 24 h. Results: Among five solvent extracts tested, the maximum efficacy was observed in the methanol extract of leaves of P. dulce. The LC50 and LC 90 values of P. dulce leaves and seeds against Cx. quinquefasciatus were 234.97, 309.24 ppm and 464.86, 570.80 ppm, respectively. No mortality was observed in controls. The Chi-square values were significant at P<0.05 level. Conclusions: From the results it can be concluded that the crude extract of P. dulce has excellent potential for controlling filariasis vector mosquito, Cx. quinquefasciatus. This is the first report on the mosquito adulticidal activity of the reported P. dulce plant.

  7. Characterisation of Culex quinquefasciatus (Diptera: Culicidae larval habitats at ground level and temporal fluctuations of larval abundance in Córdoba, Argentina

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    Marta Grech

    2013-09-01

    Full Text Available The aims of this study were to characterise the ground-level larval habitats of the mosquito Culex quinquefasciatus, to determine the relationships between habitat characteristics and larval abundance and to examine seasonal larval-stage variations in Córdoba city. Every two weeks for two years, 15 larval habitats (natural and artificial water bodies, including shallow wells, drains, retention ponds, canals and ditches were visited and sampled for larval mosquitoes. Data regarding the water depth, temperature and pH, permanence, the presence of aquatic vegetation and the density of collected mosquito larvae were recorded. Data on the average air temperatures and accumulated precipitation during the 15 days prior to each sampling date were also obtained. Cx. quinquefasciatus larvae were collected throughout the study period and were generally most abundant in the summer season. Generalised linear mixed models indicated the average air temperature and presence of dicotyledonous aquatic vegetation as variables that served as important predictors of larval densities. Additionally, permanent breeding sites supported high larval densities. In Córdoba city and possibly in other highly populated cities at the same latitude with the same environmental conditions, control programs should focus on permanent larval habitats with aquatic vegetation during the early spring, when the Cx. quinquefasciatus population begins to increase.

  8. Transcriptomic and phylogenetic analysis of Culex pipiens quinquefasciatus for three detoxification gene families

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    Yan Liangzhen

    2012-11-01

    Full Text Available Abstract Background The genomes of three major mosquito vectors of human diseases, Anopheles gambiae, Aedes aegypti, and Culex pipiens quinquefasciatus, have been previously sequenced. C. p. quinquefasciatus has the largest number of predicted protein-coding genes, which partially results from the expansion of three detoxification gene families: cytochrome P450 monooxygenases (P450, glutathione S-transferases (GST, and carboxyl/cholinesterases (CCE. However, unlike An. gambiae and Ae. aegypti, which have large amounts of gene expression data, C. p. quinquefasciatus has limited transcriptomic resources. Knowledge of complete gene expression information is very important for the exploration of the functions of genes involved in specific biological processes. In the present study, the three detoxification gene families of C. p. quinquefasciatus were analyzed for phylogenetic classification and compared with those of three other dipteran insects. Gene expression during various developmental stages and the differential expression responsible for parathion resistance were profiled using the digital gene expression (DGE technique. Results A total of 302 detoxification genes were found in C. p. quinquefasciatus, including 71 CCE, 196 P450, and 35 cytosolic GST genes. Compared with three other dipteran species, gene expansion in Culex mainly occurred in the CCE and P450 families, where the genes of α-esterases, juvenile hormone esterases, and CYP325 of the CYP4 subfamily showed the most pronounced expansion on the genome. For the five DGE libraries, 3.5-3.8 million raw tags were generated and mapped to 13314 reference genes. Among 302 detoxification genes, 225 (75% were detected for expression in at least one DGE library. One fourth of the CCE and P450 genes were detected uniquely in one stage, indicating potential developmentally regulated expression. A total of 1511 genes showed different expression levels between a parathion-resistant and a

  9. Toxicity of Beauveria bassiana-28 Mycelial Extracts on Larvae of Culex quinquefasciatus Mosquito (Diptera: Culicidae).

    Science.gov (United States)

    Vivekanandhan, Perumal; Kavitha, Thangaraj; Karthi, Sengodan; Senthil-Nathan, Sengottayan; Shivakumar, Muthugoundar Subramanian

    2018-03-03

    Microbial-based pest control is an attractive alternative to chemical insecticides. The present study sought to evaluate the toxicity of the entomopathogenic fungus Beauveria bassiana -28 ethyl acetate extracts on different larval stages and pupae of Culex quinquefasciatus mosquitoes. B. bassiana -28 ethyl acetate mycelial extracts produced mosquitocidal activity against larvae and pupae which was comparable to that of the commercial insecticide B. bassiana -22 extract. The LC 50 (lethal concentration that kills 50% of the exposed larvae) values of B. bassiana -28 extracts for 1st to 4th instar larvae and pupae were 11.538, 6.953, 5.841, 3.581 and 9.041 mg/L respectively. Our results show that B. bassiana -28 ethyl acetate mycelial extract has strong insecticidal activity against larval and pupal stages of Cx. quinquefasciatus . Fourier transform infrared spectrum study of B. bassiana -28 extract shows peaks at 3226.91; 2927.94; 1593.13; 1404.18; 1224.18; 1247.94; 1078.21; 1018.41; 229.69; and 871.82 cm -1 . Major spectral peaks were observed at 3226.91 cm -1, assigned to N-H stretching, 2927.94 cm -1 assigned to C-H bonding and 1595.13 cm -1 assigned to C-O stretching. Gas Chromatography-Mass Spectrometry studies of B. bassiana -28 ethyl acetate crude extract showed presence of six major compounds viz. N -hexadecanoic acids (13.6040%); Z,Z -9,12 octadecadienic acid (33.74%); 9-eicosyne (10.832%); heptacosane (5.148%); tetrateracontane (5.801%); and 7 hexyleicosane (5.723%). Histology of mosquito midgut tissue shows tissue lysis as a result of B.bassiana -28 extract exposure. The study shows that bioactive molecules obtained from B. bassiana -28 mycelial extract has insecticidal properties and can be used as alternative for mosquito control.

  10. Toxicity of Beauveria bassiana-28 Mycelial Extracts on Larvae of Culex quinquefasciatus Mosquito (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Perumal Vivekanandhan

    2018-03-01

    Full Text Available Microbial-based pest control is an attractive alternative to chemical insecticides. The present study sought to evaluate the toxicity of the entomopathogenic fungus Beauveria bassiana-28 ethyl acetate extracts on different larval stages and pupae of Culex quinquefasciatus mosquitoes. B. bassiana-28 ethyl acetate mycelial extracts produced mosquitocidal activity against larvae and pupae which was comparable to that of the commercial insecticide B. bassiana-22 extract. The LC50 (lethal concentration that kills 50% of the exposed larvae values of B. bassiana-28 extracts for 1st to 4th instar larvae and pupae were 11.538, 6.953, 5.841, 3.581 and 9.041 mg/L respectively. Our results show that B. bassiana-28 ethyl acetate mycelial extract has strong insecticidal activity against larval and pupal stages of Cx. quinquefasciatus. Fourier transform infrared spectrum study of B. bassiana-28 extract shows peaks at 3226.91; 2927.94; 1593.13; 1404.18; 1224.18; 1247.94; 1078.21; 1018.41; 229.69; and 871.82 cm−1. Major spectral peaks were observed at 3226.91 cm−1, assigned to N–H stretching, 2927.94 cm−1 assigned to C–H bonding and 1595.13 cm−1 assigned to C–O stretching. Gas Chromatography-Mass Spectrometry studies of B. bassiana-28 ethyl acetate crude extract showed presence of six major compounds viz. N-hexadecanoic acids (13.6040%; Z,Z-9,12 octadecadienic acid (33.74%; 9-eicosyne (10.832%; heptacosane (5.148%; tetrateracontane (5.801%; and 7 hexyleicosane (5.723%. Histology of mosquito midgut tissue shows tissue lysis as a result of B.bassiana-28 extract exposure. The study shows that bioactive molecules obtained from B. bassiana-28 mycelial extract has insecticidal properties and can be used as alternative for mosquito control.

  11. Environmental and biological factors influencing Culex pipiens quinquefasciatus Say (Diptera: Culicidae) vector competence for Saint Louis encephalitis virus.

    Science.gov (United States)

    Richards, Stephanie L; Lord, Cynthia C; Pesko, Kendra; Tabachnick, Walter J

    2009-08-01

    Complex interactions between environmental and biological factors influence the susceptibility of Culex pipiens quinquefasciatus to St. Louis encephalitis virus and could affect the epidemiology of virus transmission. Similar interactions could have epidemiologic implications for other vector-virus systems. We conducted an experiment to examine four such factors in combination: mosquito age, extrinsic incubation temperature (EIT), virus dose, and colony. The proportion of mosquitoes with body infections or disseminated infections varied between colonies, and was dependant on age, EIT, and dose. We also show that the probability of a body or leg infection interacted in complex ways between colonies, ages, EITs, and doses. The complex interactive effects of environmental and biological factors must be taken into account for studies of vector competence and epidemiology, especially when laboratory studies are used to generalize to natural transmission dynamics where the extent of variation is largely unknown.

  12. Insecticidal activity of some citrus oils against culex quinquefasciatus

    International Nuclear Information System (INIS)

    Saeed, H. M. A.

    2009-01-01

    The present study deals with the larvicidal potency of peel oils of grapefruit (Citrus paradise), sweet orange (Citrus sinensis) and lime (Citrus aurantifolia) on 4''th instar larvae of the mosquito, Culex quinquefasciatus. Orange oil was the most effective followed by grapefruit oil and then lime oil. The toxicity of the oils applied to the 4''th instar larval stage was extended to pupal and adult stages. All oils produced deleterious effects on fecundity of survivors of sublethal doses. By the aid of chemical analysis of oils, the active compound was found to be limonene, a monoterpene compound. The percentages limonene were 97.15%, 92.46% and 32.29% for orange, grapefruit and lime respectively.(Author)

  13. Vector competence of Culex quinquefasciatus say from different regions of Brazil to Dirofilaria immitis

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    Ahid Silvia Maria Mendes

    2000-01-01

    Full Text Available The vector competence of Culex quinquefasciatus from five localities in Brazil to Dirofilaria immitis was evaluated experimentally. Females from each locality were fed on an infected dog (~ 6 microfilariae/µl blood. A sample of blood fed mosquitoes were dissected approximately 1 h after blood meal. These results demonstrated that all had ingested microfilariae (mean, 4.8 to 24.6 microfilariae/mosquito. Fifteen days after the infected blood meal, the infection and infective rates were low in all populations of Cx. quinquefasciatus. The mean number of infective larvae detected in the head and proboscis of these mosquitoes was 1-1.5. The vector efficiency, the number of microfilariae ingested/number of infective larvae, was low for all populations of Cx. quinquefasciatus. However, the survival rate for all populations was high (range 50-75%. The survival rate of Aedes aegypti assayed simultaneously for comparison was low (24.7%, while the vector efficiency was much higher than for Cx. quinquefasciatus. These data suggest that the vector competence of all assayed populations of Cx. quinquefasciatus to D. immitis in Brazil is similar and that this species is a secondary vector due to its low susceptibility. Nevertheless, vector capacity may vary between populations due to differences in biting frequency on dogs that has been reported in Brazil.

  14. Role of G-protein-coupled receptor-related genes in insecticide resistance of the mosquito, Culex quinquefasciatus.

    Science.gov (United States)

    Li, Ting; Liu, Lena; Zhang, Lee; Liu, Nannan

    2014-09-29

    G-protein-coupled receptors regulate signal transduction pathways and play diverse and pivotal roles in the physiology of insects, however, the precise function of GPCRs in insecticide resistance remains unclear. Using quantitative RT-PCR and functional genomic methods, we, for the first time, explored the function of GPCRs and GPCR-related genes in insecticide resistance of mosquitoes, Culex quinquefasciatus. A comparison of the expression of 115 GPCR-related genes at a whole genome level between resistant and susceptible Culex mosquitoes identified one and three GPCR-related genes that were up-regulated in highly resistant Culex mosquito strains, HAmCq(G8) and MAmCq(G6), respectively. To characterize the function of these up-regulated GPCR-related genes in resistance, the up-regulated GPCR-related genes were knockdown in HAmCq(G8) and MAmCq(G6) using RNAi technique. Knockdown of these four GPCR-related genes not only decreased resistance of the mosquitoes to permethrin but also repressed the expression of four insecticide resistance-related P450 genes, suggesting the role of GPCR-related genes in resistance is involved in the regulation of resistance P450 gene expression. This results help in understanding of molecular regulation of resistance development in Cx. quinquefasciatus.

  15. Relationships between infection, dissemination, and transmission of West Nile virus RNA in Culex pipiens quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Richards, Stephanie L; Anderson, Sheri L; Lord, Cynthia C; Smartt, Chelsea T; Tabachnick, Walter J

    2012-01-01

    Culex pipiens quinquefasciatus Say fed blood containing 6.8 +/- 0.3 logs (mean +/- SE) plaque-forming units of West Nile virus (WNV)/ml were maintained at 28 degrees C for incubation periods (IP) of 7, 14, or 21 d. Several attributes of vector competence were determined at each IP using quantitative real-time reverse transcriptase polymerase chain reaction to estimate plaque forming unit equivalents including: infection rate (WNV-positive abdomens), dissemination rate (WNV-positive legs or thoraces), combined dissemination rate (WNV-positive legs and thoraces), transmission rate (WNV-positive saliva), and WNV titers in abdomens, legs, thoraces, and saliva. Each rate increased or was equivalent with increasing IP. Mosquitoes transmitting WNV in saliva also had significantly higher IP-dependent WNV titers in abdomens, legs, and thoraces. Titers of WNV in abdomens were significantly correlated with titers in legs and thoraces, but the degree of association changed with IP. However, titers of abdomens, legs, and thoraces were not correlated with WNV presence or titer in the saliva. The results show that WNV presence or titer in the saliva of infected Cx. p. quinquefasciatus was not directly influenced by processes involved in WNV replication in other tissues. The processes controlling midgut infection and escape are, in part, independent from the infection processes in other tissues. The relationship between infection, dissemination, and transmission varied over time. The infection and replication of WNV in different tissues is likely influenced by different barriers encountered during the extrinsic incubation period. The significance of these observations for understanding vector competence is discussed.

  16. Impact of extrinsic incubation temperature and virus exposure on vector competence of Culex pipiens quinquefasciatus Say (Diptera: Culicidae) for West Nile virus.

    Science.gov (United States)

    Richards, Stephanie L; Mores, Christopher N; Lord, Cynthia C; Tabachnick, Walter J

    2007-01-01

    Culex pipiens quinquefasciatus Say mosquitoes from a laboratory colony were exposed to artificial blood meals containing West Nile virus (WNV) and held at incubation temperatures approximating average daily temperatures that occur during Florida arboviral periods. Mosquitoes fed blood meals containing 6.2 logs plaque-forming units (pfu) WNV/mL and held at 25 degrees C, 28 degrees C, or 30 degrees C for 13 days exhibited significantly different rates of infection (30%, 52%, 93%) and dissemination (33%, 22%, 81%) across temperatures. In a separate experiment, Cx. p. quinquefasciatus mosquitoes were provided artificial blood meals with graded doses of WNV from 3.7 to 5.8 logs pfu/mL and maintained at 28 degrees C for 13 days. Rates of infection increased as a function of virus dose, but neither body titers nor dissemination rates were significantly different for mosquitoes that were infected by ingesting different amounts of WNV. Our findings indicate that efficiency of WNV infection and dissemination, and thereby transmission, in Cx. p. quinquefasciatus populations similar to our tested colony may also be diminished when fed blood meals containing less than 5.8 logs pfu WNV/mL and when environmental temperature falls below 30 degrees C. The relationship between the infection rate and dissemination rate changed at different temperatures. This relationship is likely complex and dependent on diverse interactions between factors such as incubation temperature and viremia, which should also be assessed for field populations.

  17. Mosquito larvicidal activity of seaweeds extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus

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    Mohamed Yacoob Syed Ali

    2013-06-01

    Full Text Available Objective: To identify the larvicidal activity of the seaweed extracts against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus Methods: Seaweed extracts of Ulva lactuca, Caulerpa racemosa (C. racemosa, Sargassum microystum, Caulerpa scalpelliformis, Gracilaria corticata, Turbinaria decurrens, Turbinaria conoides and Caulerpa toxifolia were dissolved in DMSO to prepare a graded series of concentration. The test for the larvicidal effect of seaweeds against mosquitos larvae was conducted in accordance with the WHO standard method. Batches of 25 early 4th instar larvae of three mosquitoes were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (10-100 µg. Each experiment was conducted with triplicate with concurrent a control group. Results: Among the seaweeds extract, C. racemosa showed toxicity against 4th instar larvae of Aedes aegypti, Culex quinquefasciatus, Anopheles stephensi with equivalent LC 50 value (0.055 6依0.010 3 µg/mL, (0.067 5依0.136 0 µg/mL and (0.066 1 依0.007 6 µg/mL, respectively. Conclusions: The present study concluded that, the mosquito larvicidal property of C. racemosa might be the prospective alternative source to control the mosquitoes.

  18. Mosquito larvicidal activity of Rauvolfia serpentina L. seeds against Culex quinquefasciatus Say.

    Science.gov (United States)

    Das, Dipanwita; Chandra, Goutam

    2012-01-01

    To establish the larvicidal activities, if any of solvent extracts of Rauvolfia serpentina (R. serpentina) L. seeds against Culex quinquefasciatus (Cx. quinquefasciatus) Say, 1823 as target species. Seeds of R. serpentina were extracted with five solvents graded according to the polarity [viz. petroleum ether, benzene, ethyl acetate, acetone and absolute alcohol] continuing one after another with the same seeds. Mortality rate with petroleum ether extract was significantly higher than other extracts. The mortality rates of late 3rd instar larvae were 50.33±5.51, 10.00±1.00, 0.00±0.00, 21.33±1.53 and 0.00±0.00 in 100 ppm concentration of petroleum ether, benzene, ethyl acetate, acetone and absolute alcohol respectively, after 24 h of exposure period. Results of this study show that petroleum ether extract of R. serpentina seed may be considered as a potent source of mosquito larvicidal agent. Copyright © 2012 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  19. Differential effect of human ivermectin treatment on blood feeding Anopheles gambiae and Culex quinquefasciatus

    DEFF Research Database (Denmark)

    Derua, Yahya A.; Kisinza, William N.; Simonsen, Paul Erik

    2015-01-01

    BACKGROUND: Widespread and large scale use of ivermectin in humans and domestic animals can have unexpected effects on non-target organisms. As a search for a possible explanation for an observed longitudinal decline in density of anopheline vector mosquitoes, but not in Culex quinquefasciatus...... to receive either ivermectin or placebo. Twenty four hours after treatment, one volunteer from each group was concurrently exposed to 50 laboratory reared An. gambiae on one arm and 50 laboratory reared Cx. quinquefasciatus on the other arm for 15-30 minutes. Engorged mosquitoes were maintained on 10...

  20. Larvicidal potential of some plants from West Africa against Culex quinquefasciatus (Say) and Anopheles gambiae Giles (Diptera: Culicidae).

    Science.gov (United States)

    Azokou, Alain; Koné, Mamidou W; Koudou, Benjamin G; Tra Bi, Honora F

    2013-01-01

    Mosquitoes increased resistance to insecticides, and environmental concerns about the use of insecticides, pose a major challenge in the search for new molecules to deplete and incapacitate mosquito populations. Plants are the valuable source as practices consisting in exploiting plant materials as repellents, and are still in wide use throughout developing countries. The aim of the present study was to screen plants from Cτte d'Ivoire for larvicidal activity against mosquitoes. Resistant and sensitive larvae (III and IV instar) of Anopheles gambiae and Culex quinquefasciatus were exposed to crude ethanol extracts (90%) of 45 plants and viability observed after 30 min, 6, 12 and 24 h postincubation. After partition of active extracts, each fraction (hexane and chloroform washed with NaCl 1%, tannins and aqueous) was tested using the same protocol at various concentrations (1000- 31.2 ppm). Of 49 extracts tested, 7 exhibited high potential (LC50 = 80 to 370 ppm) against resistant and sensitive III and IV instar larvae of An. gambiae and Cx. quinquefasciatus. These extracts were from Cissus populnea, Cochlospermum planchonii, Heliotropium indicum, Phyllanthus amarus, Vitex grandifolia and Alchornea cordifolia. However, three most active plant species (LC50 = 80- 180 ppm) were Cs. populnea, Cm. planchonii and P. amarus Their hexane and chloroform fractions showed high larvicidal activity. This study demonstrated that plants from Cτte d'Ivoire have a real potential for malaria, yellow fever, filarial and dengue vector control. Those could be used as sources or provide lead compounds for the development of safe plant-based biocides.

  1. Larvicidal potentiality, longevity and fecundity inhibitory activities of Bacillus sphaericus (Bs G3-IV on vector mosquitoes, Aedes aegypti and Culex quinquefasciatus

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    Arjunan Nareshkumar

    2012-12-01

    Full Text Available Intervention measures to control the transmission of vector-borne diseases include control of the vector population. In mosquito control, synthetic insecticides used against both the larvae (larvicides and adults (adulticides create numerous problems, such as environmental pollution, insecticide resistance and toxic hazards to humans. In the present study, a bacterial pesticide, Bacillus sphaericus (Bs G3-IV, was used to control the dengue and filarial vectors, Aedes aegypti and Culex quinquefasciatus. Bacillus sphaericus (Bs G3-IV was very effective against Aedes aegypti and Culex quinquefasciatus, showing significant larval mortality. Evaluated lethal concentrations (LC50 and LC90 were age-dependent, with early instars requiring a lower concentration compared with later stages of mosquitoes. Culex quinquefasciatus was more susceptible to Bacillus sphaericus (Bs G3-IV than was Aedes aegypti. Fecundity rate was highly reduced after treatment with different concentrations of Bacillus sphaericus (Bs G3-IV. Larval and pupal longevity both decreased after treatment with Bacillus sphaericus (Bs G3-IV, total number of days was lower in the B. sphaericus treatments compared with the control. Our results show the bacterial pesticide Bacillus sphaericus (Bs G3-IV to be an effective mosquito control agent that can be used for more integrated pest management programs.

  2. How Diverse Detrital Environments Influence Nutrient Stoichiometry between Males and Females of the Co-Occurring Container Mosquitoes Aedes albopictus, Ae. aegypti, and Culex quinquefasciatus.

    Science.gov (United States)

    Yee, Donald A; Kaufman, Michael G; Ezeakacha, Nnaemeka F

    2015-01-01

    Allocation patterns of carbon and nitrogen in animals are influenced by food quality and quantity, as well as by inherent metabolic and physiological constraints within organisms. Whole body stoichiometry also may vary between the sexes who differ in development rates and reproductive allocation patterns. In aquatic containers, such as tree holes and tires, detrital inputs, which vary in amounts of carbon and nitrogen, form the basis of the mosquito-dominated food web. Differences in development times and mass between male and female mosquitoes may be the result of different reproductive constraints, which could also influence patterns of nutrient allocation. We examined development time, survival, and adult mass for males and females of three co-occurring species, Aedes albopictus, Ae. aegypti, and Culex quinquefasciatus, across environments with different ratios of animal and leaf detritus. We quantified the contribution of detritus to biomass using stable isotope analysis and measured tissue carbon and nitrogen concentrations among species and between the sexes. Development times were shorter and adults were heavier for Aedes in animal versus leaf-only environments, whereas Culex development times were invariant across detritus types. Aedes displayed similar survival across detritus types whereas C. quinquefasciatus showed decreased survival with increasing leaf detritus. All species had lower values of 15N and 13C in leaf-only detritus compared to animal, however, Aedes generally had lower tissue nitrogen compared to C. quinquefasciatus. There were no differences in the C:N ratio between male and female Aedes, however, Aedes were different than C. quinquefasciatus adults, with male C. quinquefasciatus significantly higher than females. Culex quinquefasciatus was homeostatic across detrital environments. These results allow us to hypothesize an underlying stoichiometric explanation for the variation in performance of different container species under similar

  3. Competence of Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus Mosquitoes as Zika Virus Vectors, China

    Science.gov (United States)

    Liu, Zhuanzhuan; Zhou, Tengfei; Lai, Zetian; Zhang, Zhenhong; Jia, Zhirong; Zhou, Guofa; Williams, Tricia; Xu, Jiabao; Gu, Jinbao; Zhou, Xiaohong; Lin, Lifeng; Yan, Guiyun

    2017-01-01

    In China, the prevention and control of Zika virus disease has been a public health threat since the first imported case was reported in February 2016. To determine the vector competence of potential vector mosquito species, we experimentally infected Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquitoes and determined infection rates, dissemination rates, and transmission rates. We found the highest vector competence for the imported Zika virus in Ae. aegypti mosquitoes, some susceptibility of Ae. albopictus mosquitoes, but no transmission ability for Cx. quinquefasciatus mosquitoes. Considering that, in China, Ae. albopictus mosquitoes are widely distributed but Ae. aegypti mosquito distribution is limited, Ae. albopictus mosquitoes are a potential primary vector for Zika virus and should be targeted in vector control strategies. PMID:28430562

  4. Competence of Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus Mosquitoes as Zika Virus Vectors, China.

    Science.gov (United States)

    Liu, Zhuanzhuan; Zhou, Tengfei; Lai, Zetian; Zhang, Zhenhong; Jia, Zhirong; Zhou, Guofa; Williams, Tricia; Xu, Jiabao; Gu, Jinbao; Zhou, Xiaohong; Lin, Lifeng; Yan, Guiyun; Chen, Xiao-Guang

    2017-07-01

    In China, the prevention and control of Zika virus disease has been a public health threat since the first imported case was reported in February 2016. To determine the vector competence of potential vector mosquito species, we experimentally infected Aedes aegypti, Ae. albopictus, and Culex quinquefasciatus mosquitoes and determined infection rates, dissemination rates, and transmission rates. We found the highest vector competence for the imported Zika virus in Ae. aegypti mosquitoes, some susceptibility of Ae. albopictus mosquitoes, but no transmission ability for Cx. quinquefasciatus mosquitoes. Considering that, in China, Ae. albopictus mosquitoes are widely distributed but Ae. aegypti mosquito distribution is limited, Ae. albopictus mosquitoes are a potential primary vector for Zika virus and should be targeted in vector control strategies.

  5. Effect of temperature on life history traits during immature development of Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae) from Córdoba city, Argentina.

    Science.gov (United States)

    Grech, Marta G; Sartor, Paolo D; Almirón, Walter R; Ludueña-Almeida, Francisco F

    2015-06-01

    We investigated how ambient temperature under fluctuating conditions affects the larval-pupal immature traits of Aedes aegypti and Culex quinquefasciatus mosquitoes from Córdoba city, Argentina, and established each species development threshold and physiological time. Based on life tables, three cohorts of each mosquito species were reared in the laboratory under small fluctuating temperatures conditions of 15.2±1.7°C, 17.9±1.6°C, 21.6±0.7°C and 25.3±0.4°C for Ae. aegypti, and 16.6±1.7°C, 18.7±1.7°C and 25.2±0.3°C for Cx. quinquefasciatus. Immature development time and survival values, and also thermal development threshold and physiological time were estimated. Development times of all larval and pupal stages of Ae. aegypti and Cx. quinquefasciatus were significantly affected by the rearing temperatures, decreasing when temperature increased. Mean Ae. aegypti total (larva+pupa) development time ranged from 21.9 to 8.6 days, at 15.2 and 25.3°C, whereas, for Cx. quinquefasciatus varied between 23.5 to 9.2 days at 16.6 and 25.2°C, respectively. Larval and pupal survival of both species was affected by different rearing temperatures, increasing in general as temperature increased. For Ae. aegypti the total immature survival ranged from 26% at 15.2°C to 92% at 21.6°C; however, temperature did not have significant effect on this variable. The total immature survival of Cx. quinquefasciatus was significantly and positively affected by temperatures, ranging from 32 to 88%, at 16.6 and 25.2°C. The temperature development threshold and the physiological time estimated for Ae. aegypti and Cx. quinquefasciatus were 11.11°C and 93.74 degree-days, and 10.96°C and 136.87 degree-days, respectively. The results of the present study showed that temperature significantly affects the larval-pupal immature traits of these mosquito species of sanitary importance, from the central region of Argentina. All the parameters recorded are useful for the development of

  6. Septic tanks as larval habitats for the mosquitoes Aedes aegypti and Culex quinquefasciatus in Playa-Playita, Puerto Rico.

    Science.gov (United States)

    Burke, R; Barrera, R; Lewis, M; Kluchinsky, T; Claborn, D

    2010-06-01

    Adult Aedes aegypti (Linnaeus) (Diptera: Culicidae) were previously recovered from emergence traps on septic tanks in southeastern Puerto Rico. In this study we quantified immature mosquito abundance and its relationship with structural variables of the septic tanks and chemical properties of the water containing raw sewage. A miniaturized floating funnel trap was used to sample 89 septic tanks for larvae in the Puerto Rican community of Playa-Playita. Aedes aegypti larvae were recovered from 18% of the sampled tanks (10.3 larvae per septic tank per day). Larval presence was positively associated with cracking of the septic tank walls and uncovered access ports. Larval abundance was positively associated with cracking of the septic tank walls and larger tank surface areas, and inversely associated with the total dissolved solids (TDS). Culex quinquefasciatus (Say) larvae were also recovered from 74% of the septic tanks (129.6 larvae per septic tank per day). Larval presence was negatively associated with TDS in the water and larval abundance was positively associated with cracking of the septic tank walls. A screened, plastic emergence trap was used to sample 93 septic tanks within the community for Ae. aegypti and Cx. quinquefasciatus adults. Aedes aegypti adults were recovered from 49% of the sampled tanks (8.7 adults per septic tank per day) and Cx. quinquefasciatus adults were recovered from 97% of the sampled tanks (155.5 adults per septic tank per day). Aedes aegypti adult presence was positively associated with cracking, uncapped openings and septic water pH. The Ae. aegypti adult counts were positively associated with cracking and inversely associated with TDS and conductivity. This study marks the first published record of the recovery of Ae. aegypti larvae from holding tanks containing raw sewage in the Caribbean region. Our study indicates that Ae. aegypti larvae are present in sewage water and that septic tanks have at least the potential to maintain

  7. A first note on Japanese encephalitis virus isolation from Culex quinquefasciatus Say in Northern West Bengal.

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    V. Thenmozhi

    2014-03-01

    Full Text Available Japanese encephalitis (JE is endemic in many parts of India including the state of West Bengal. In West Bengal, the first major outbreaks of JE occurred in the districts of Bankura and Burdwan in 1973. The Culex vishnui subgroup of mosquitoes has been implicated as major vectors of JE. However in India, JE virus (JEV has been isolated from 16 species of mosquitoes. During September 2011, JE cases were reported from four districts -Jalpaiguri, Darjeeling, Dinajpur and Cooch Behar of West Bengal (North. Adult mosquitoes were collected, identified, pooled and screened for JEV using antigen capture ELISA. Out of 279 mosquito pools tested, one pool of Cx. pseudovishnui and three pools of Cx. quinquefasciatus were found positive for JEV. The ELISA positive pools were further confirmed as JEV by insect bioassay (Toxo-IFA. Two pools of Cx. quinquefasciatus were confirmed as JEV. This represents the first report of JEV isolation from Cx. quinquefasciatus in West Bengal.

  8. Evaluation of aqueous and ethanol extract of bioactive medicinal plant, Cassia didymobotrya (Fresenius) Irwin & Barneby against immature stages of filarial vector, Culex quinquefasciatus Say (Diptera: Culicidae).

    Science.gov (United States)

    Nagappan, Raja

    2012-09-01

    To evaluate aqueous and ethanol extract of Cassia didymobotrya leaves against immature stages of Culex quinquefasciatus. The mortality rate of immature mosquitoes was tested in wide and narrow range concentration of the plant extract based on WHO standard protocol. The wide range concentration tested in the present study was 10 000, 1 000, 100, 10 and 1 mg/L and narrow range concentration was 50, 100, 150, 200 and 250 mg/L. 2nd instar larvae exposed to 100 mg/L and above concentration of ethanol extract showed 100% mortality. Remaining stages such as 3rd, 4th and pupa, 100% mortality was observed at 1 000 mg/L and above concentration after 24 h exposure period. In aqueous extract all the stages 100% mortality was recorded at 1 000 mg/L and above concentration. In narrow range concentration 2nd instar larvae 100% mortality was observed at 150 mg/L and above concentration of ethanol extract. The remaining stages 100% mortality was recorded at 250 mg/L. In aqueous extract all the tested immature stages 100% mortality was observed at 250 mg/L concentration after 24 h exposure period. The results clearly indicate that the rate of mortality was based dose of the plant extract and stage of the mosquitoes. From this study it is confirmed and concluded that Cassia didymobotrya is having active principle which is responsible for controlling Culex quinquefasciatus. The isolation of bioactive molecules and development of simple formulation technique is important for large scale implementation.

  9. Environmental and social-demographic predictors of the southern house mosquito Culex quinquefasciatus in New Orleans, Louisiana.

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    Moise, Imelda K; Riegel, Claudia; Muturi, Ephantus J

    2018-04-17

    Understanding the major predictors of disease vectors such as mosquitoes can guide the development of effective and timely strategies for mitigating vector-borne disease outbreaks. This study examined the influence of selected environmental, weather and sociodemographic factors on the spatial and temporal distribution of the southern house mosquito Culex quinquefasciatus Say in New Orleans, Louisiana, USA. Adult mosquitoes were collected over a 4-year period (2006, 2008, 2009 and 2010) using CDC gravid traps. Socio-demographic predictors were obtained from the United States Census Bureau, 2005-2009 American Community Survey and the City of New Orleans Department of Code Enforcement. Linear mixed effects models and ERDAS image processing software were used for statistical analysis and image processing. Only two of the 22 predictors examined were significant predictors of Cx. quinquefasciatus abundance. Mean temperature during the week of mosquito collection was positively associated with Cx. quinquefasciatus abundance while developed high intensity areas were negatively associated with Cx. quinquefasciatus abundance. The findings of this study illustrate the power and utility of integrating biophysical and sociodemographic data using GIS analysis to identify the biophysical and sociodemographic processes that increase the risk of vector mosquito abundance. This knowledge can inform development of accurate predictive models that ensure timely implementation of mosquito control interventions.

  10. Impact of bifenthrin on honeybees and Culex quinquefasciatus.

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    Qualls, Whitney A; Xue, Rui-De; Zhong, He

    2010-06-01

    The impact of bifenthrin on honeybees, Apis mellifera (Hymenoptera: Apidae) was evaluated in both laboratory and semifield assays. Ten serial dilutions of bifenthrin and an acetone control using the bottle bioassay protocol were used in the laboratory to determine killing time after 15-, 30-, and 60-min honeybee exposure. Both dose and exposure time significantly affected honeybee mortality (df = 6, F = 10.9, P Bifenthrin was applied at 9.7 ml/liter, 19.5 ml/liter, and 29.5 ml/liter of water to common landscape vegetation, Melampodium paludosum Melanie (show star) and Duranta erecta L. (golden dewdrop); a water control was also used. Bee mortality was significantly higher (P < 0.05, df = 2, F = 20.8) at 29.5 ml/liter compared to the mortality at 19.5-ml/liter and 9.7-ml/liter application rates after 24-h exposure to the treated vegetation. Mortality of Culex quinquefasciatus exposed to treated vegetation was significantly (P < 0.05, df = 10, F = 114) different by week and by application rate.

  11. Bioactivity of sea grass against the malarial fever mosquito Culex quinquefasciatus

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    Suburamaniyan Vijayakumar

    2014-08-01

    Full Text Available Objective: To identify the larvicidal activity of the seagrass extracts against Culex quinquefasciatus (Cx. quinquefasciatus Methods: Seagrass extracts, Halodule pinifolia (H. pinifolia, Cymodocea serrulata (C. serrulata and Thalasia testudinum (T. testudinum were dissolved in dimethylsulfoxide to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Cx. quinquefasciatus were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01 mg-0.1 mg. After 24 h the mortality rate was identified with the formulae [(% of test mortality - % of control mortality/(100 - % of control mortality]伊100. Each experiment was conducted with three replicates and a concurrent control group. A control group consisted of 1 mL of dimethylsulfoxide and 199 mL of distilled water only. Results: The root extract of H. pinifolia showed maximum larvicidal activity with minimum concentration of extract of LC 50 value of (0.614依0.006 µg/mL with lower confidence limit-upper confidence limit value of (0.052-0.072 and LC90 value of 0.9120 µg/mL followed by leaf extract of C. serrulata LC 50 value of (0.074依0.008 µg/mL and LC90 value of 0.1487 µg/mL. T. testudinum leaf extract showed LC 50 value of (0.082依0.006 µg/mL. The regression equation of root and leaf extract of H. pinifolia for 4 th instar larvae of Cx. quinquefasciatus were Y=5.229+1.36x (R2=0.993 and Y=2.369+1.21x (R2=0.878 respectively and analysis of variation was significant at P<0.05 level. The result of the preliminary phytochemical constituents showed the presence of saponin, steroids, terpenoid, phenols, protein and sugars. Conclusions: From the present study the ethanolic extracts of seagrass of H. pinifolia possess lead compound for development of larvicidal activity.

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

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

    2014-05-01

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

  13. Protection against mosquito vectors Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus using a novel insect repellent, ethyl anthranilate.

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    Islam, Johirul; Zaman, Kamaruz; Tyagi, Varun; Duarah, Sanjukta; Dhiman, Sunil; Chattopadhyay, Pronobesh

    2017-10-01

    Growing concern on the application of synthetic mosquito repellents in the recent years has instigated the identification and development of better alternatives to control different mosquito-borne diseases. In view of above, present investigation evaluates the repellent activity of ethyl anthranilate (EA), a non-toxic, FDA approved volatile food additive against three known mosquito vectors namely, Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus under laboratory conditions following standard protocols. Three concentration levels (2%, 5% and 10% w/v) of EA were tested against all the three selected mosquito species employing K & D module and arm-in-cage method to determine the effective dose (ED 50 ) and complete protection time (CPT), respectively. The repellent activity of EA was further investigated by modified arm-in-cage method to determine the protection over extended spatial ranges against all mosquito species. All behavioural situations were compared with the well-documented repellent N,N-diethylphenyl acetamide (DEPA) as a positive control. The findings demonstrated that EA exhibited significant repellent activity against all the three mosquitoes species. The ED 50 values of EA, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus were found to be 0.96%, 5.4% and 3.6% w/v, respectively. At the concentration of 10% w/v, it provided CPTs of 60, 60 and 30min, respectively, against Aedes aegypti, Anopheles stephensi and Culex quinquefasciatus mosquitoes. Again in spatial repellency evaluation, EA was found to be extremely effective in repelling all the three tested species of mosquitoes. Ethyl anthranilate provided comparable results to standard repellent DEPA during the study. Results have concluded that the currently evaluated chemical, EA has potential repellent activity against some well established mosquito vectors. The study emphasizes that repellent activity of EA could be exploited for developing effective, eco

  14. Larvicidal Activity of Cassia occidentalis (Linn. against the Larvae of Bancroftian Filariasis Vector Mosquito Culex quinquefasciatus

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    Deepak Kumar

    2014-01-01

    Full Text Available Background & Objectives. The plan of this work was to study the larvicidal activity of Cassia occidentalis (Linn. against the larvae of Culex quinquefasciatus. These larvae are the most significant vectors. They transmit the parasites and pathogens which cause a deadly disease like filariasis, dengue, yellow fever, malaria, Japanese encephalitis, chikungunya, and so forth, which are considered harmful towards the population in tropic and subtropical regions. Methods. The preliminary laboratory trail was undertaken to determine the efficacy of petroleum ether and N-butanol extract of dried whole plant of Cassia occidentalis (Linn. belonging to the family Caesalpiniaceae at various concentrations against the late third instar larvae of Culex quinquefasciatus by following the WHO guidelines. Results. The results suggest that 100% mortality effect of petroleum ether and N-butanol extract of Cassia occidentalis (Linn. was observed at 200 and 300 ppm (parts per million. The results obviously showed use of plants in insect control as an alternative method for minimizing the noxious effect of some pesticide compounds on the environment. Thus the extract of Cassia occidentalis (Linn. is claimed as more selective and biodegradable agent. Conclusion. This study justified that plant Cassia occidentalis (Linn. has a realistic mortality result for larvae of filarial vector. This is safe to individual and communities against mosquitoes. It is a natural weapon for mosquito control.

  15. Larvicidal Activity of Cassia occidentalis (Linn.) against the Larvae of Bancroftian Filariasis Vector Mosquito Culex quinquefasciatus.

    Science.gov (United States)

    Kumar, Deepak; Chawla, Rakesh; Dhamodaram, P; Balakrishnan, N

    2014-01-01

    Background & Objectives. The plan of this work was to study the larvicidal activity of Cassia occidentalis (Linn.) against the larvae of Culex quinquefasciatus. These larvae are the most significant vectors. They transmit the parasites and pathogens which cause a deadly disease like filariasis, dengue, yellow fever, malaria, Japanese encephalitis, chikungunya, and so forth, which are considered harmful towards the population in tropic and subtropical regions. Methods. The preliminary laboratory trail was undertaken to determine the efficacy of petroleum ether and N-butanol extract of dried whole plant of Cassia occidentalis (Linn.) belonging to the family Caesalpiniaceae at various concentrations against the late third instar larvae of Culex quinquefasciatus by following the WHO guidelines. Results. The results suggest that 100% mortality effect of petroleum ether and N-butanol extract of Cassia occidentalis (Linn.) was observed at 200 and 300 ppm (parts per million). The results obviously showed use of plants in insect control as an alternative method for minimizing the noxious effect of some pesticide compounds on the environment. Thus the extract of Cassia occidentalis (Linn.) is claimed as more selective and biodegradable agent. Conclusion. This study justified that plant Cassia occidentalis (Linn.) has a realistic mortality result for larvae of filarial vector. This is safe to individual and communities against mosquitoes. It is a natural weapon for mosquito control.

  16. Development of the immature stages of Culex (Culex saltanensis Dyar (Diptera, Culicidae under laboratory conditions

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    João Antonio C. Zequi

    2012-03-01

    Full Text Available Development of the immature stages of Culex (Culex saltanensis Dyar (Diptera, Culicidae under laboratory conditions. Culex (Culex saltanensis Dyar, 1928 is becoming frequent and abundant in natural and artificial breeding sites in urban and rural areas of Brazil. This study contributes to the knowledge of the biology of a Brazilian strain of C. saltanensis. The development of specimens reared individually or grouped was observed. The study was conducted at a constant temperature of 27 ± 2°C, 14L:10D photoperiod and 80 ± 5% relative humidity. The immature stages were observed every 6 hours until adult emergence, which occurred in 12.29 days among individually reared specimens and in 13.12 days among group-reared specimens. Egg rafts for the experiment were obtained from the laboratory and field. Eggs hatched at a rate of 97.48 ± 2.32%. More eggs per egg raft were obtained from the field than from the laboratory. Males from individually reared specimens emerged in 12.29 ± 1.11 days and females in 13.12 ± 1.58 days. The male-female ratio was 1:1. Larval survival rate was higher than 85% for larvae reared isolated and higher than 95% for group-reared larvae. The Culex saltanensis life cycle was completed within 12 to 14 days, where larval instars I and IV took the most time to develop and the pupae, the shortest.

  17. Genetic diversity of Wolbachia endosymbionts in Culex quinquefasciatus from Hawai`i, Midway Atoll, and Samoa

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    Atkinson, Carter T.; Watcher-Weatherwax, William; Lapointe, Dennis

    2016-01-01

    Incompatible insect techniques are potential methods for controlling Culex quinquefasciatus and avian disease transmission in Hawai‘i without the use of pesticides or genetically modified organisms. The approach is based on naturally occurring sperm-egg incompatibilities within the Culex pipiens complex that are controlled by different strains of the bacterial endosymbiont Wolbachia pipientis (wPip). Incompatibilities can be unidirectional (crosses between males infected with strain A and females infected with strain B are fertile, while reciprocal crosses are not) or bidirectional (reciprocal crosses between sexes with different wPip strains are infertile). The technique depends on release of sufficient numbers of male mosquitoes infected with an incompatible wPip strain to suppress mosquito populations and reduce transmission of introduced avian malaria (Plasmodium relictum) and Avipoxvirus in native forest bird habitats. Both diseases are difficult to manage using more traditional methods based on removal and treatment of larval habitats and coordination of multiple approaches may be needed to control this vector. We characterized the diversity of Wolbachia strains in C. quinquefasciatus from Hawai‘i, Kaua‘i, Midway Atoll, and American Samoa with a variety of genetic markers to identify compatibility groups and their distribution within and between islands. We confirmed the presence of wPip with multilocus sequence typing, tested for local genetic variability using 16 WO prophage genes, and identified similarities to strains from other parts of the world with a transposable element (tr1). We also tested for genetic differences in ankyrin motifs (ank2 and pk1) which have been used to classify wPip strains into five worldwide groups (wPip1–wPip5) that vary in compatibility with each other based on experimental crosses. We found a mixture of both widely distributed and site specific genotypes based on presence or absence of WO prophage and transposable

  18. Entomopathogenic fungus generated Nanoparticles for enhancement of efficacy in Culex quinquefasciatus and Anopheles stephensi

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    N. SONI, S. PRAKASH

    2012-05-01

    Full Text Available Objective: To evaluate to efficacy of silver and gold generated larvicide with the help of entomopathogenic fungus Chrysosporium tropicum against the Culex quinquefasciatus and Anopheles stephensi larvae. Methods: The silver and gold nanoparticles were quantified and observed by the Micro-scan reader and X-ray diffraction technique. The micrographs of silver and gold nanoparticles were obtained by the Transmission electron microscope and Scanning electron microscope. The larvicidal efficacy was then performed at six different log concentrations by the probit analysis. Results: The characterization study confirmed the spherical shaped and sized (20-50 and 2-15 nm of silver and gold nanoparticles. The all larval stages of Cx. quinquefasciatus were found more susceptible to the synthesized silver nanoparticles. Whereas, the larvae of An. stephensi were found more susceptible to larvicide synthesized with gold nanoparticles. Conclusions: The results suggested that the silver and gold nanoparticles generated by the entomopathogenic fungus C. tropicum is an environmentally safer and greener approach for mosquito control and new possibility in vector control strategy.

  19. Vapor toxicity of five volatile pyrethroids against Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles quadrimaculatus (Diptera: Culicidae).

    Science.gov (United States)

    Bibbs, Christopher S; Tsikolia, Maia; Bloomquist, Jeffrey R; Bernier, Ulrich R; Xue, Rui-De; Kaufman, Phillip E

    2018-05-25

    Mosquito mortality has been documented in numerous studies of spatial repellents but the concentration-dependent toxicity of spatial repellent vapors has not been documented. To address this issue, prallethrin, flumethrin, metofluthrin, transfluthrin, and meperfluthrin were selected for comparative study against Aedes albopictus (Skuse), Ae. aegypti (L.), Culex quinquefasciatus Say, and Anopheles quadrimaculatus Say. Mosquito were exposed to vapors of each chemical for 2h, 4h, and 24h with mortality recorded at each time point. A second experiment involved exposing mosquitoes to vapors for 2h, then transferring them to untreated holding containers and held for 24h. For these mosquitoes, readings were only taken after 24h to allow for metabolic detoxification and recovery. The LC 50 and LC 90 data indicated that transfluthrin and meperfluthrin had the greatest toxicity across all species, followed by metofluthrin, prallethrin, and flumethrin. Our findings, through the direct comparison of these compounds, suggest that transfluthrin, meperfluthrin, and metofluthrin be considered for further development. The vapor toxicity for the aforementioned compounds significantly exceeds prallethrin, which is currently market available as an adulticidal active ingredient in public health pest control. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  20. Evaluación de la actividad insecticida de un producto granulado a base de Bacillus sphaericus sobre larvas de Anopheles albimanus y Culex quinquefasciatus en condiciones experimentales

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    Estrella Cárdenas

    2009-01-01

    Full Text Available Culex quinquefasciatus causa alergias por las picaduras y ha sido asociado con la encefalitis equina, mientras que Anopheles albimanus es vector de malaria. El objetivo fue evaluar la toxicidad de un producto granulado a base de Bacillus sphaericus sobre larvas de Culex quinquefasciatus y Anopheles albimanus. El estudio fue realizado sobre larvas de C. quinquefasciatus (Sibaté y Villavicencio y An albimanus (Cartagena y Barranquilla. Las concentraciones ensayadas de B. sphaericus fueron: 20, 40, 60, 80, 100, 120, 140, 160, 180, 200 y 500 ppm para larvas de An. albimanus y para larvas de C. quinquefasciatus fueron: 2, 4, 6, 8, 10, 12, 14 y 16 ppm. Se utilizaron 20 larvas en tres repeticiones por cada concentración del producto y el tiempo de exposición fue de 48 horas. El producto de B. sphaericus mostró alta mortalidad (entre 80 y 100% a bajas concentraciones (8 y 12 ppm para larvas de C. quinquefasciatus; mientras que para larvas de An. albimanus a concentraciones más altas (entre 40 y 200 ppm la mortalidad no superó el 50%. La CL50 Logit fue 176 ppm y la Probit fue 192 ppm de B. sphaericus para larvas de An. albimanus; mientras que para larvas de C. quinquefasciatus la CL50 Logit fue 1, 9 ppm y la Probit fue 2, 2 ppm. Se concluye que las larvas de C. quinquefasciatus fueron más susceptibles a bajas concentraciones (2 a 12 ppm de B. sphaericus, mientras que las larvas de An. albimanus mostraron alta toxicidad a concentraciones de 500 ppm.

  1. Residential characteristics aggravating infestation by Culex quinquefasciatus in a region of Northeastern Brazil

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    Juliana Cavalcanti Correia

    2012-12-01

    Full Text Available OBJECTIVE: Analyse how basic sanitation conditions, water supply and housing conditions affect the concentration of Culex quinquefasciatus METHODS: Populations of C. quinquefasciatus in 61 houses in the municipality of Olinda, PE, were monitored between October 2009 and October 2010. Observations were carried out in homes without the presence of preferred breeding sites in order to identify characteristics that may be aggravating factors for the development of the mosquito. Five aggravating factors were analysed: vegetation cover surrounding the home, number of residents/home, water storage, sewage drainage and water drainage. These characteristics were analysed in terms of presence or absence and as indicators of the degree of infestation, which was estimated through monitoring the concentration of eggs (oviposition traps - BR-OVT and adults (CDC light traps. RESULTS: Sewage drainage to a rudimentary septic tank or to the open air was the most frequent aggravating factor in the homes (91.8%, although the presence of vegetation was the only characteristic that significantly influenced the increase in the number of egg rafts (p = 0.02. The BR-OVT achieved positive results in 95.1% of the evaluations, with the presence of at least one egg raft per month. A total of 2,366 adults were caught, with a mosquito/room/night ratio of 32.9. No significant difference was found in the number of mosquitoes caught in the homes. CONCLUSIONS: Although the sanitation and water supply influence the population density of C. quinquefasciatus, residence features that are not usually considered in control measures can be aggravating factors in sustaining the mosquito population.

  2. Insecticides resistance in the Culex quinquefasciatus populations from northern Thailand and possible resistance mechanisms.

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    Yanola, Jintana; Chamnanya, Saowanee; Lumjuan, Nongkran; Somboon, Pradya

    2015-09-01

    The mosquito vector Culex quinquefasciatus is known to be resistant to insecticides worldwide, including Thailand. This study was the first investigation of the insecticide resistance mechanisms, involving metabolic detoxification and target site insensitivity in C. quinquefasciatus from Thailand. Adult females reared from field-caught larvae from six provinces of northern Thailand were determined for resistant status by exposing to 0.05% deltamethrin, 0.75% permethrin and 5% malathion papers using the standard WHO susceptibility test. The overall mortality rates were 45.8%, 11.4% and 80.2%, respectively. A fragment of voltage-gated sodium channel gene was amplified and sequenced to identify the knock down resistance (kdr) mutation. The ace-1 gene mutation was determined by using PCR-RFLP. The L1014F kdr mutation was observed in all populations, but the homozygous mutant F/F1014 genotype was found only in two of the six provinces where the kdr mutation was significantly correlated with deltamethrin resistance. However, none of mosquitoes had the G119S mutation in the ace-1 gene. A laboratory deltamethrin resistant strain, Cq_CM_R, has been established showing a highly resistant level after selection for a few generations. The mutant F1014 allele frequency was significantly increased after one generation of selection. A synergist assay was performed to assess the metabolic detoxifying enzymes. Addition of bis(4-nitrophenyl)-phosphate (BNPP) and diethyl maleate (DEM), inhibitors of esterases and glutathione S-transferases (GST), respectively, into the larval bioassay of the Cq_CM strain with deltamethrin showed no significant reduction. By contrast, addition of piperonyl butoxide (PBO), an inhibitor of cytochrome P450 monooxygenases, showed a 9-fold reduction of resistance. Resistance to pyrethroids in C. quinquefasciatus is widely distributed in northern Thailand. This study reports for the first time for the detection of the L1014F kdr mutation in wild populations

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

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    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2013-12-01

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

  4. Residential characteristics aggravating infestation by Culex quinquefasciatus in a region of Northeastern Brazil Características agravantes por infestación residencial de Culex quinquefasciatus, en una región del Noreste de Brasil Características agravantes por infestação residencial de Culex quinquefasciatus, em Olinda, PE

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    Juliana Cavalcanti Correia

    2012-12-01

    Full Text Available OBJECTIVE: Analyse how basic sanitation conditions, water supply and housing conditions affect the concentration of Culex quinquefasciatus METHODS: Populations of C. quinquefasciatus in 61 houses in the municipality of Olinda, PE, were monitored between October 2009 and October 2010. Observations were carried out in homes without the presence of preferred breeding sites in order to identify characteristics that may be aggravating factors for the development of the mosquito. Five aggravating factors were analysed: vegetation cover surrounding the home, number of residents/home, water storage, sewage drainage and water drainage. These characteristics were analysed in terms of presence or absence and as indicators of the degree of infestation, which was estimated through monitoring the concentration of eggs (oviposition traps - BR-OVT and adults (CDC light traps. RESULTS: Sewage drainage to a rudimentary septic tank or to the open air was the most frequent aggravating factor in the homes (91.8%, although the presence of vegetation was the only characteristic that significantly influenced the increase in the number of egg rafts (p = 0.02. The BR-OVT achieved positive results in 95.1% of the evaluations, with the presence of at least one egg raft per month. A total of 2,366 adults were caught, with a mosquito/room/night ratio of 32.9. No significant difference was found in the number of mosquitoes caught in the homes. CONCLUSIONS: Although the sanitation and water supply influence the population density of C. quinquefasciatus, residence features that are not usually considered in control measures can be aggravating factors in sustaining the mosquito population.OBJETIVO: Analizar como las condiciones de saneamiento básico, abastecimiento de agua y habitaciones afectan la densidad de Culex quinquefasciatus MÉTODOS: se monitoreó la población de C. quinquefasciatus en 61 residencias del municipio de Olinda, PE, Brasil, de octubre de 2009 a octubre de

  5. Synthesis of some novel phosphorylated and thiophosphorylated benzimidazoles and benzothiazoles and their evaluation for larvicidal potential to Aedes albopictus and Culex quinquefasciatus.

    Science.gov (United States)

    Bandyopadhyay, Prabal; Sathe, Manisha; Tikar, Sachin N; Yadav, Ruchi; Sharma, Pratibha; Kumar, Ashok; Kaushik, M P

    2014-07-01

    Series of benzimidazole and benzothiazole linked phosphoramidates and phosphoramidothioates (5a-j) and benzimidazole linked phenylphosphoramidates and phenylphosphoramidothioates (10a-e) were synthesized. The title compounds were preliminary screened for mosquito larvicidal properties against Aedes albopictus and Culex quinquefasciatus at different concentration from 40 to 5 mg/L. Among the screened compounds three compounds revealed potential larvicidal effects with 100% mortality in the order of 10e>5j>5e. Compound 10e was found to be the most toxic compound to Ae. albopictus and Cx. quinquefasciatus. The LC50 of 10e against Ae. albopictus was found to be 6.42 and 5.25 mg/L at 24 and 48 h, respectively, whereas it was 7.01 and 3.88 mg/L, respectively in Cx. quinquefasciatus. Temephos was used as positive control. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Toxicity of seaweed-synthesized silver nanoparticles against the filariasis vector Culex quinquefasciatus and its impact on predation efficiency of the cyclopoid crustacean Mesocyclops longisetus.

    Science.gov (United States)

    Murugan, Kadarkarai; Benelli, Giovanni; Ayyappan, Suganya; Dinesh, Devakumar; Panneerselvam, Chellasamy; Nicoletti, Marcello; Hwang, Jiang-Shiou; Kumar, Palanisamy Mahesh; Subramaniam, Jayapal; Suresh, Udaiyan

    2015-06-01

    Nearly 1.4 billion people in 73 countries worldwide are threatened by lymphatic filariasis, a parasitic infection that leads to a disease commonly known as elephantiasis. Filariasis is vectored by mosquitoes, with special reference to the genus Culex. The main control tool against mosquito larvae is represented by treatments with organophosphates and insect growth regulators, with negative effects on human health and the environment. Recently, green-synthesized nanoparticles have been proposed as highly effective larvicidals against mosquito vectors. In this research, we attempted a reply to the following question: do green-synthesized nanoparticles affect predation rates of copepods against mosquito larvae? We proposed a novel method of seaweed-mediated synthesis of silver nanoparticles using the frond extract of Caulerpa scalpelliformis. The toxicity of the seaweed extract and silver nanoparticles was assessed against the filarial vector Culex quinquefasciatus. Then, we evaluated the predatory efficiency of the cyclopoid crustacean Mesocyclops longisetus against larval instars of C. quinquefasciatus in a nanoparticle-contaminated water environment. Green-synthesized silver nanoparticles were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction (XRD). In mosquitocidal assays, the LC₅₀ values of the C. scalpelliformis extract against C. quinquefasciatus were 31.38 ppm (I), 46.49 ppm (II), 75.79 ppm (III), 102.26 ppm (IV), and 138.89 ppm (pupa), while LC₅₀ of silver nanoparticles were 3.08 ppm, (I), 3.49 ppm (II), 4.64 ppm (III), 5.86 ppm (IV), and 7.33 ppm (pupa). The predatory efficiency of the copepod M. longisetus in the control treatment was 78 and 59% against I and II instar larvae of C. quinquefasciatus. In a nanoparticle-contaminated environment, predation efficiency was 84 and 63%, respectively. Predation was higher against first instar larvae over other instars

  7. Repellency of essential oils extracted from Thai native plants against Aedes aegypti (Linn.) and Culex quinquefasciatus (Say).

    Science.gov (United States)

    Phukerd, Ubol; Soonwera, Mayura

    2014-09-01

    Repellent activity of essential oils derived from 10 Thai native plants, belonging to three families were evaluated against female Aedes aegypti and Culex quinquefasciatus and to compare them with a commercial chemical repellents (DEET; N,N-diethyl-3-methylbenzamide 20% w/w; Sketolene Shield). Each test repellent was applied at 1, 5, and 10% concentrations for testing by arm in cage method. The results showed significant differences in repellency among the repellents by mosquito species. The protection time of the essential oils against Ae. aegypti ranged from 3 to 30 min. According to the Culex mosquito, it showed the protection time ranged from 3 to 260 min. 10 % Boesenbergia rotunda essential oil provided the best efficiency, in which protection time was 4.3 h as equal as DEET. The essential oils which exhibited protection time more than 2 h were those of 10% Zingiber zerumbet, Litsea petiolata, Curcuma zedoaria, and Zingiber cassumunar essential oils (3.1, 2.8, 2.6, and 2.3 h, respectively). The biting percentage ranged from 0.9 to 18.0% and 0.8 to 3.6% against Ae. aegypti and Cx. quinquefasciatus, respectively. The results revealed that the potential of essential oil extracted from B. rotunda, Z. zerumbet, L. petiolata, C. zedoaria, and Z. cassumunar had attributes of good repellent and deterred biting. We recommend the five essential oils for further study to develop as commercial repellents.

  8. Larvicidal potential of Asteraceae family endophytic actinomycetes against Culex quinquefasciatus mosquito larvae.

    Science.gov (United States)

    Tanvir, Rabia; Sajid, Imran; Hasnain, Shahida

    2014-01-01

    Pakistan is blessed with plants of Asteraceae family with known medicinal background used for centuries by Hakims (traditional physicians). Keeping in mind the background of their anti-larval potential, a total of 21 endophytic actinomycetes were isolated from four Asteraceae plants and screened against the first and fourth instar stages of Culex quinquefasciatus Say mosquito larvae. Of the 21 isolates, 6 of them gave strong larvicidal activity (80-100% mortality) in the screening results and 4 isolates gave a potent larvicidal activity (100% mortality) at the fourth instar stage. These isolates belonged to different species within the actinomycetes group, namely Streptomyces albovinaceus and Streptomyces badius. This communication reports the larvicidal potential of endophytic actinomycetes residing within the native Asteraceae plants in Pakistan. The study suggests further exploration through large-scale productions leading to the identification of the larvicidal compounds.

  9. Genetic diversity based on 28S rDNA sequences among populations of Culex quinquefasciatus collected at different locations in Tamil Nadu, India.

    Science.gov (United States)

    Sakthivelkumar, S; Ramaraj, P; Veeramani, V; Janarthanan, S

    2015-09-01

    The basis of the present study was to distinguish the existence of any genetic variability among populations of Culex quinquefasciatus which would be a valuable tool in the management of mosquito control programmes. In the present study, population of Cx. quinquefasciatus collected at different locations in Tamil Nadu were analyzed for their genetic variation based on 28S rDNA D2 region nucleotide sequences. A high degree of genetic polymorphism was detected in the sequences of D2 region of 28S rDNA on the predicted secondary structures in spite of high nucleotide sequence similarity. The findings based on secondary structure using rDNA sequences suggested the existence of a complex genotypic diversity of Cx. quinquefasciatus population collected at different locations of Tamil Nadu, India. This complexity in genetic diversity in a single mosquito population collected at different locations is considered an important issue towards their influence and nature of vector potential of these mosquitoes.

  10. Pengaruh Pengasapan (Thermal Fogging Insektisida Piretroid (Malation 95% Terhadap Nyamuk Aedes aegypti dan Culex quinquefasciatus di Pemukiman

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    Hasan Boesri

    2009-12-01

    Full Text Available The evaluation of piretroid insecticide (active ingredient Malation 95% was con-ducted in Sub district Tengarang, Semarang Segency, Central Java Province. The insecti-cide was applied using thermal fogging method for dosages of 125, 250, 375, 500 and 625 ml/ha (diluted in diesel to 10 litters. The evaluation of the efficacy was conducted against two mosquito species, Aedes aegypti (the main dengue haemorrhagic fever and Culex quinquefasciatus (the urban lymphatic fil-ariasis vector. Result of the evaluation was revealed that dosages of 500 and 625 ml/ha were effective against both tested mosquito species indoor and outdoor.

  11. Loss of genetic diversity in Culex quinquefasciatus targeted by a lymphatic filariasis vector control program in Recife, Brazil.

    Science.gov (United States)

    Cartaxo, Marina F S; Ayres, Constância F J; Weetman, David

    2011-09-01

    Recife is one of the largest cities in north-eastern Brazil and is endemic for lymphatic filariasis transmitted by Culex quinquefasciatus. Since 2003 a control program has targeted mosquito larvae by elimination of breeding sites and bimonthly application of Bacillus sphaericus. To assess the impact of this program on the local vector population we monitored the genetic diversity and differentiation of Cx. quinquefasciatus using microsatellites and a B. sphaericus-resistance associated mutation (cqm1(REC)) over a 3-year period. We detected a significant but gradual decline in allelic diversity, which, coupled with subtle temporal genetic structure, suggests a major impact of the control program on the vector population. Selection on cqm1(REC) does not appear to be involved with loss of neutral diversity from the population, with no temporal trend in resistant allele frequency and no correlation with microsatellite differentiation. The evidence for short-term genetic drift we detected suggests a low ratio of effective population size: census population size for Cx. quinquefasciatus, perhaps coupled with strong geographically-restricted population structure. Spatial definition of populations will be an important step for success of an expanded vector control program. Copyright © 2011 Royal Society of Tropical Medicine and Hygiene. Published by Elsevier Ltd. All rights reserved.

  12. Comparative efficacy of IR3535 and deet as repellents against adult Aedes aegypti and Culex quinquefasciatus.

    Science.gov (United States)

    Cilek, J E; Petersen, J L; Hallmon, C E

    2004-09-01

    Arm-in-cage laboratory evaluations of 2 proprietary formulations of the mosquito repellents IR3535 and N,N-diethyl-3-methylbenzamide (deet; aqueous cream, hydroalcoholic spray) were made with 10 and 20% concentrations of each repellent. Also, 4 commercially available products containing IR3535 (Expedition insect repellent 20.07% active ingredient [AI], Bug Guard Plus with SPF30 sunscreen 7.5% AI, Bug Guard Plus with SPF15 sunscreen 7.5% AI, and Bug Guard Plus 7.5% AI) were tested. All comparisons were made on an equal formulation or concentration basis. Eight volunteers tested all formulations or products 3 times against laboratory-reared, Aedes aegypti and Culex quinquefasciatus mosquitoes (6-10 days old). Products were applied to a forearm at the rate of 0.002 g/cm2. The other forearm was not treated and served as a control. Elapsed time to 1st and 2nd consecutive bite was recorded. Mean protection time (i.e., time to 1st bite) with proprietary formulations of IR3535 were comparable to those of deet, with 20% concentrations providing greater protection against Ae. aegypti (3 h) and Cx. quinquefasciatus (6 h). Mean protection time for commercial products containing IR3535 ranged from nearly 90 to 170 min for Ae. aegypti and 3.5 to 6.5 h for Cx. quinquefasciatus. Mean time to the 2nd bite was similar to time to 1st bite for each mosquito species, product, and formulation.

  13. Oviposition Attractancy of Bacterial Culture Filtrates: response of Culex quinquefasciatus

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    S Poonam

    2002-04-01

    Full Text Available Oviposition attractants could be used for monitoring as well as controlling mosquitoes by attracting them to lay eggs at chosen sites. In the present study, culture filtrates of seven bacterial species were tested for their attractancy against gravid females of Culex quinquefasciatus. When their oviposition active indices (OAI were studied, the culture filtrates of Bacillus cereus and Pseudomonas fluorescens exhibited oviposition attractancy (OAI = >0.3 at 100 ppm and the OAI were respectively 0.70 and 0.47. Culture filtrates of B. thuringiensis var. israelensis (wild type, B. t. var. israelensis (mutant and B. sphaericus showed attractancy at 2000 ppm with OAI of respectively 0.71, 0.59 and 0.68. However, the OAI of B. megaterium as well as Azospirillum brasilense was 0.13 (at 2000 ppm, which was less than 0.3 required to be considered them as attractants. When the oviposition attractancy of the bacterial culture filtrates were compared with that of a known oviposition attractant, p-cresol (at 10 ppm, the culture filtrates of B. t. var. israelensis (wild type and B. cereus were found to be more active than p-cresol, respectively with 64.2 and 54.3% oviposition.

  14. The effect of three environmental conditions on the fitness of cytochrome P450 monooxygenase-mediated permethrin resistance in Culex pipiens quinquefasciatus

    OpenAIRE

    Lazzaro Brian P; Hardstone Melissa C; Scott Jeffrey G

    2009-01-01

    Abstract Background The evolution of insecticide resistance and persistence of resistance phenotypes are influenced by the fitness of resistance alleles in the absence of insecticide pressure. Experimental determination of fitness is difficult, but fitness can be inferred by measuring changes in allele frequencies in appropriate environments. We conducted allele competition experiments by crossing two highly related strains of Culex pipiens quinquefasciatus mosquitoes. One strain (ISOP450) wa...

  15. Estirpes de Bacillus thuringiensis efetivas contra insetos das ordens Lepidoptera, Coleoptera e Diptera Bacillus thuringiensis strains effective against insects of Lepidoptera, Coleoptera and Diptera orders

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    Lílian Botelho Praça

    2004-01-01

    Full Text Available O objetivo deste trabalho foi selecionar entre 300 estirpes de Bacillus thuringiensis as efetivas simultaneamente contra larvas de Spodoptera frugiperda J.E. Smith e Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus e Culex quinquefasciatus Say (Diptera: Culicidae. Foram selecionadas duas estirpes de B. thuringiensis, denominadas S234 e S997, que apresentaram atividade contra as três ordens de insetos. As estirpes foram caracterizadas por métodos morfológicos, bioquímicos e moleculares. As mesmas apresentaram duas proteínas principais de 130 e 65 kDa, produtos de reação em cadeia da polimerase de tamanho esperado para a detecção dos genes cry1Aa, cry1Ab, cry1Ac, cry1B e cry2 e cristais bipiramidais, cubóides e esféricos.The aim of this work was to select among 300 strains of Bacillus thuringiensis those which are simultaneously effective against larvae of Spodoptera frugiperda J.E. Smith and Anticarsia gemmatalis Hübner (Lepidoptera: Noctuidae, Anthonomus grandis Boheman (Coleoptera: Curculionidae, Aedes aegypti Linnaeus and Culex quinquefasciatus Say (Diptera: Culicidae. Two strains of B. thuringiensis were selected, S234 and S997, which presented activity against those three insect orders. Both strains were characterized by morphological, biochemical and molecular methods. They have presented two main proteins with 130 and 65 kDa, polimerase chain reaction products with expected sizes for detection of the genes cry1Aa, cry1Ab, cry1Ac, cry1B and cry2 and bipiramidal, cubical and spherical crystals.

  16. Attractiveness of botanical infusions to ovipositing Culex quinquefasciatus, Cx. nigripalpus, and Cx. erraticus in San Antonio, Texas.

    Science.gov (United States)

    McPhatter, Lee P; Debboun, Mustapha

    2009-12-01

    Field experiments were conducted on the Fort Sam Houston Military Reservation, San Antonio, TX, in fall 2008 to observe the attractiveness of selected botanical infusions to ovipositing female mosquitoes. The following infusions were tested in Centers for Disease Control and Prevention gravid traps: Bermuda grass (Cynodon dactylon), oak leaf (Quercus virginiana), acacia leaf (Acacia schaffneri), rabbit chow (alfalfa pellets), and algae (Spirogyra sp.). Four (Bermuda, acacia, oak, and algae) of the 5 infusions were effective in collecting Culex quinquefasciatus, Cx. nigripalpus, and Cx. erraticus. Of the 4 infusions, Bermuda collected the greatest number of the mosquitoes sampled. Female Aedes albopictus mosquitoes were collected in moderate numbers during this study.

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

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    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.

  18. Ovicidal and adulticidal potential of leaf and seed extract of Albizia lebbeck (L.) Benth. (Family: Fabaceae) against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi (Diptera: Culicidae).

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-05-01

    Several diseases are associated to the mosquito-human interaction. Mosquitoes are the carriers of severe and well-known illnesses such as malaria, arboviral encephalitis, dengue fever, chikungunya fever, West Nile virus, and yellow fever. These diseases produce significant morbidity and mortality in humans and livestock around the world. In the present study, hexane, benzene, chloroform, ethyl acetate, and methanol extracts of leaf and seed of Albizia lebbeck were assayed for their toxicity against three important vector mosquitoes, viz., Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The mean percent hatchability of the eggs was observed after 48 h post-treatment. The percent hatchability was inversely proportional to the concentration of extract and directly proportional to the eggs. All the five solvent extracts showed moderate ovicidal activity; however, the methanol extract showed the highest ovicidal activity. One hundred percent mortality was observed at 250, 200, and 150 ppm for leaf methanol extract and 375, 300, and 225 ppm for seed methanol extract of A. lebbeck against C. quinquefasciatus, Ae. aegypti, and An. stephensi, respectively. The adulticidal activity of plant leaf and seed extracts showed moderate toxic effect on the adult mosquitoes after 24 h of exposure period. However, the highest adulticidal activity was observed in the leaf methanol extract of A. lebbeck against An. stephensi where the LC₅₀ and LC₉₀ values were 65.12 and 117.70 ppm, respectively. Compared to leaf extracts, seeds have low potency against three mosquito species. No mortality was recorded in the control. Our data suggest that the crude hexane, benzene, chloroform, ethyl acetate, and methanol solvent extracts of A. lebbeck have the potential to be used as an eco-friendly approach for the control of the An. stephensi, Ae. aegypti, and C. quinquefasciatus. These results suggest that the leaf and seed extracts have the potential to be used as an ideal

  19. Acute larvicidal toxicity of five essential oils (Pinus nigra, Hyssopus officinalis, Satureja montana, Aloysia citrodora and Pelargonium graveolens) against the filariasis vector Culex quinquefasciatus: Synergistic and antagonistic effects.

    Science.gov (United States)

    Benelli, Giovanni; Pavela, Roman; Canale, Angelo; Cianfaglione, Kevin; Ciaschetti, Giampiero; Conti, Fabio; Nicoletti, Marcello; Senthil-Nathan, Sengottayan; Mehlhorn, Heinz; Maggi, Filippo

    2017-04-01

    Mosquito vector control is facing a number of important and timely challenges, mainly due to the rapid development of pesticide resistance and environmental concerns. In this scenario, screening of botanical resources for their mosquitocidal activity may offer effective and eco-friendly tools against Culicidae vectors. Culex quinquefasciatus Say (Diptera: Culicidae) is a vector of lymphatic filariasis and of dangerous arboviral diseases, such as West Nile and St. Louis encephalitis. In this study, the chemical composition of five essential oils obtained from different plants, namely Pinus nigra J.F. Arnold var. italica (Pinaceae), Hyssopus officinalis L. subsp. aristatus (Lamiaceae), Satureja montana L. subsp. montana (Lamiaceae), Aloysia citriodora Palau (Verbenaceae) and Pelargonium graveolens L'Hér (Geraniaceae), was investigated by GC-MS analysis. Furthermore, it was evaluated their acute toxicity on larvae of C. quinquefasciatus. Then, the most effective oils were selected, in order to focus on the potential synergistic and antagonistic effects, testing them in binary mixtures on C. quinquefasciatus larvae. Results showed that the higher effectiveness was obtained by S. montana subsp. montana essential oil (LC 50 =25.6μL·L -1 ), followed by P. nigra var. italica (LC 50 =49.8μL·L -1 ) and A. citriodora (LC 50 =65.6μL·L -1 ), while the other essential oils showed LC 50 values higher than 90μL·L -1 . The larvicidal effectiveness can be enhanced by preparing simple binary mixtures of essential oils, such as S. montana+A. citriodora (ratio 1:1), which showed higher larvicidal toxicity (LC 50 =18.3μL·L -1 ). On the other hand, testing S. montana+P. nigra (1:1) an antagonistic effect was detected, leading to a LC 50 (72.5μL·L -1 ) higher than the LC 50 values calculated for the two oils tested separately. Overall, our results add useful knowledge to allow the employ of synergistic essential oil blends as effective, cheap and eco-friendly mosquito

  20. Spatial variation in host feeding patterns of Culex tarsalis and the Culex pipiens complex (Diptera: Culicidae) in California.

    Science.gov (United States)

    Thiemann, T C; Lemenager, D A; Kluh, S; Carroll, B D; Lothrop, H D; Reisen, W K

    2012-07-01

    West Nile virus (family Flaviviridae, genus Flavivirus, WNV) is now endemic in California across a variety of ecological regions that support a wide diversity of potential avian and mammalian host species. Because different avian hosts have varying competence for WNV, determining the blood-feeding patterns of Culex (Diptera: Culicidae) vectors is a key component in understanding the maintenance and amplification of the virus as well as tangential transmission to humans and horses. We investigated the blood-feeding patterns of Culex tarsalis Coquillett and members of the Culex pipiens L. complex from southern to northern California. Nearly 100 different host species were identified from 1,487 bloodmeals, by using the mitochondrial gene cytochrome c oxidase I (COI). Cx. tarsalis fed on a higher diversity of hosts and more frequently on nonhuman mammals than did the Cx. pipiens complex. Several WNV-competent host species, including house finch and house sparrow, were common bloodmeal sources for both vector species across several biomes and could account for WNV maintenance and amplification in these areas. Highly competent American crow, western scrub-jay and yellow-billed magpie also were fed upon often when available and are likely important as amplifying hosts for WNV in some areas. Neither species fed frequently on humans (Cx. pipiens complex [0.4%], Cx. tarsalis [0.2%]), but with high abundance, both species could serve as both enzootic and bridge vectors for WNV.

  1. Biological control of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps

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    Willian Marinho Dourado Coelho

    2017-08-01

    Full Text Available Mosquitoes can act as vectors of important diseases such as malaria, dengue, Zika virus, yellow fever, Chikungunya and Mayaro fever, in addition to filariasis. The use of insecticides, larvicides, bed nets and repellents, besides the use of drugs as chemoprevention and the treatment of the sick are currently the pillars of the control of these vectors. We studied the biological control against of Anopheles darlingi, Aedes aegypti and Culex quinquefasciatus larvae using shrimps of the species M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii. Larvae of mosquitoes were collected from the breeding environment and placed in a 500 and 1000 l tank containing 60 shrimps/m2. The predatory activity was evaluated for 30 days and, in all groups it was observed that 100% of the larvae were consumed in few minutes. In the environment, these same species of crustaceans were released in water bodies with the presence of larvae of these insects. In just 72 h there was a marked reduction of the larvae in the release sites of shrimps. Similarly, there was a reduction in the number of adult mosquitoes caught near the breeding sites, allowing to infer that, in places where the crustaceans were released, the predatory activity on the larvae of mosquitoes was sufficient to reduce the number of adult mosquitoes p ≤ 0,05. This is the first description of the predatory activity of M. pantanalense, M. amazonicum, M. brasiliense and M. jelskii on An. darlingi, A. aegypti and C. quinquefasciatus larvae, constituting an important tool of biological control of these parasites-vectors.

  2. The Distribution of Culex spp (Diptera: Culicidae in Selected Endemic Lymphatic Filariasis Villages in Bandung District West Java Indonesia

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    Endang Puji Astuti

    2017-12-01

    Full Text Available Abstrak. Data entomologis terkait aspek bionomik dan distribusi nyamuk vektor lymphatic filariasis di Kabupaten Bandung masih sangat sedikit meskipun kabupaten ini sudah mengimplementasikan POPM Filariasis dari tahun 2009. Tujuan penelitian adalah mengindentifikasi spesies nyamuk potensial penular lymphatic filariasis dan habitatnya di wilayah endemis filariasis yaitu Kecamatan Majalaya, Kabupaten Bandung. Survei dilaksanakan selama 2 bulan yaitu September – Oktober 2013 di dua desa Kecamatan Majalaya. Kegiatannya adalah pencidukan larva (termasuk plotting habitat, salinitas, temperatur air, pH, penangkapan nyamuk dewasa menggunakan metode human landing (dalam dan luar rumah serta resting (dinding rumah dan kandang ternak. Hasil penangkapan nyamuk memperoleh enam spesies yang berhasil diidentifikasi. Culex quinquefasciatus dan Cx. tritaeniorhynchus adalah nyamuk yang dominan tertangkap dengan puncak gigitan antara jam 21.00-01.00 WIB. Terdapat lima tempat perkembangbiakan potensial yang teramati disekitar desa tersebut yang terdiri dari kolam ikan yang terbengkalai dan persawahan dengan salinitas 0‰, temperatur air 28,5-29°C, pH 6-7. Meskipun MHD dan MBR vektor filariasis yaitu Cx. quinquefasciatus di wilayah tersebut relatif rendah, penularan masih dapat terjadi karena didukung dengan kondisi lingkungan dan keberadaan nyamuk vektor tersebut di wilayah iniKata kunci: lymphatic filariasis; tempat perkembangbiakan; Cx. quinquefasciatus; kepadatan, BandungAbstract. Bandung district has been implemented mass drug administration (MDA program since 2009, but little is known about entomological data especially about bionomic aspects and distribution of lymphatic filariasis (LF mosquito vectors. This study was aimed to identify potential LF mosquito species and its potential breeding sites in two LF endemic villages in Majalaya, Bandung district. The observational study was conducted in September-October 2013. Mosquito larvae were collected by a

  3. Larvicidal activity of Lawsonia inermis and Murraya exotica leaves extract on filarial vector, Culex quinquefasciatus.

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    K. Dass

    2014-06-01

    Full Text Available Extensive use of synthetic and chemical insecticides to control mosquitoes result in environment hazards and development of resistance in vector species. This research work is about an alternative mosquito control method that is considered as safe to environment and non-target species and also bio-degradable. Hence an attempt was made to study the larvicidal effect of the extract of Lawsonia inermis and Murraya exotica leaves on III and IV instar larva and pupa of Culex quinquefasciatus. The LC50 value of Murraya exotica for III and IV instar larvae and pupae is 135.539 ppm, 154.361 ppm and 178.571 ppm respectively. Likewise for Lawsonia inermis it is 139.057 for III instar, 163.630 for IV instar and 188.151 for the pupa. Of these, two plants Murraya exotica plant extract is more effective than the Lawsonia inermis.

  4. The Morphological Variations of Culex pipiens Larvae (Diptera: Culicidae in Yazd Province, Central Iran

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    H Dehghan

    2010-12-01

    Full Text Available "nAbstract "nBackground: Culex pipiens complex shows variations in morphological and biological characters including differ­ent biological forms and has medical and veterinary importance. Because of having morphological variations, some­times it is not easy to separate this species from Cx. quinquefasciatus and Cx. torrentium. The aim of this study was to  identify the  Culex pipiens complex species in order to use in control programs in the future. "nMethods: This study was carried out in two randomly selected rural villages in Yazd County, eastern Iran using dip­ping technique from April to October 2009. The data were analyzed using SPSS software version 16. "nResults: Average of siphon index in fourth-instrar larvae was 3.86±0.03, the minimum and maximum were calculated 2.43 and 5.14, respectively. Siphon/Saddle index was measured as average, minimum and maximum 3.2±0.2, 2.78, and 4.42 respectively. In our study, only 4 specimens had single seta 1 on segments III and VI (2.5% and the remaining beard double seta (97.5%. The maximum 3-6 branches seta 1a-S and 1b-S (95% were observed on siphon. "nConclusion: More populations of Culex pipiens from different areas of Iran need to be studied to gain complete informa­tion about the taxonomy and ecology of the species in the country. "n  "nKeywords: Culex pipiens complex, larvae, taxonomy, Iran

  5. Insect repellent activity of medicinal plant oils against Aedes aegypti (Linn.), Anopheles minimus (Theobald) and Culex quinquefasciatus Say based on protection time and biting rate.

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    Phasomkusolsil, Siriporn; Soonwera, Mayura

    2010-07-01

    This study investigated insect bite protection and length of the protection with 30 repellents which were divided into 3 categories: plant oil, essential oil and essential oil with ethyl alcohol, tested against three mosquito species, Aedes aegypti, Anopheles minimus and Culex quinquefasciatus, under laboratory conditions. The plant oil group was comprised of Phlai (Zingiber cassumunar) and Sweet basil (Ocimum basilicum). Both substances were effective as repellents and feeding deterrents against An. minimus (205 minutes protection time and a biting rate of 0.9%), Cx. quinquefasciatus (165 minutes protection time and 0.9% biting rate) and Ae. aegypti (90 minutes protection time and 0.8% biting rate). Essential oil from citronella grass (Cymbopogon nardus) exhibited protection against biting from all 3 mosquito species: for An. minimus, Cx. quinquefasciatus and Ae. aegypti, the results were 130 minutes and 0.9%, 140 minutes and 0.8%, and 115 minutes and 0.8%, respectively. The period of protection time against Ae. aegypti for all repellent candidates tested was lower than the Thai Industrial Standards Institute (TISI) determined time of greater than 2 hours.

  6. Studies on effects of Andrographis paniculata (Burm.f.) and Andrographis lineata nees (Family: Acanthaceae) extracts against two mosquitoes Culex quinquefasciatus (Say.) and Aedes aegypti (Linn.).

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    Renugadevi, G; Ramanathan, T; Shanmuga, priya R; Thirunavukkarasu, P

    2013-03-01

    To investigate the studies on effects of Andrographis paniculata (A. paniculata) (Burm.f.) and Andrographis lineata (A. lineata) nees (Family: Acanthaceae) extracts against two mosquitoes Culex quinquefasciatus (Cx. quinquefasciatus) (Say.) and Aedes aegypti (Ae. aegypti) (Linn.). The aqueous and petroleum ether extracts of two plant species, A. paniculata and A. lineate were examined against the larvae of A. aegypti (L.) and Cx. quinquefasciatus with gradually increasing concentration ie. from 50 to 200 ppm of solvent extracts and to test their activity in combination with each other. In a 24 h bioassay experiment with plant extracts, highest mortalities were recorded at 200 ppm of concentrations for leaves of A. lineta and A. paniculata individually. For combination effect, only 150 ppm of the mixture of solvent extracts of petroleum ether: aqueous (1:1) extracts showed 100% mortality after 24 h of exposure. The results show that, insecticides of plant combination is ecofriend and has better larvicidal activity compared to individual extracts. Copyright © 2013 Hainan Medical College. Published by Elsevier B.V. All rights reserved.

  7. Monthly prevalence and diversity of mosquitoes (Diptera: Culicidae in Fars Province, Southern Iran

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    Davood Keshavarzi

    2017-02-01

    Full Text Available Objective: To get new data about the ecology of mosquitoes, which would be valuable to develop programs for future provision of mosquito controls in the study area. Methods: During April to September 2012, larvae of mosquitoes were collected from six counties in south of Fars Province using dipping method. Characteristics of larval breeding places were considered based on water conditions. Species diversity was examined in terms of alpha and beta measures, with the intent of comparing mosquito diversity according to the typology of regions. Results: During this investigation, totally, 5 057 larvae of mosquitoes belonging to 5 genera and 17 different mosquito species were recognized, namely, Anopheles dthali, Anopheles fluviatilis, Anopheles stephensi, Anopheles superpictus, Culex quinquefasciatus (Cx. quinquefasciatus, Culex mimeticus, Culex perexiguus, Culex pipiens (Cx. pipiens, Culex tritaeniorhynchus, Culex theileri (Cx. theileri, Culex tritaeniorhynchus, Culex sinaiticus, Culex torrentium, Culex modestus, Ochlerotatus caspius, Culiseta longiareolata and Aedes vexans (Ae. vexans. This is the first record of Ae. vexans, Culex perexiguus and Culex modestus in the Province. Cx. pipiens (27.3%, Cx. theileri (15.9% and Cx. quinquefasciatus (9.4% were the most abundant species found respectively. Cx. pipiens reached the highest density in August and July, while Cx. theileri, Cx. quinquefasciatus and Ae. vexans were found in high numbers in June. Diversity analysis indicated the highest species diversity in the Mohr County (Margalef index of 1.41 and Shannon index of 1.7 and the lowest species diversity in the Lamerd County (Margalef index of 0.33 and Shannon index of 0.38. Conclusions: Regarding to this research, there are some potential vectors of medical and veterinary importance in Fars Province. Results of the present study may serve as a basis for risk assessment of emerging mosquito-borne diseases.

  8. Cytonuclear Epistasis Controls the Density of Symbiont Wolbachia pipientis in Nongonadal Tissues of Mosquito Culex quinquefasciatus.

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    Emerson, Kevin J; Glaser, Robert L

    2017-08-07

    Wolbachia pipientis , a bacterial symbiont infecting arthropods and nematodes, is vertically transmitted through the female germline and manipulates its host's reproduction to favor infected females. Wolbachia also infects somatic tissues where it can cause nonreproductive phenotypes in its host, including resistance to viral pathogens. Wolbachia -mediated phenotypes are strongly associated with the density of Wolbachia in host tissues. Little is known, however, about how Wolbachia density is regulated in native or heterologous hosts. Here, we measure the broad-sense heritability of Wolbachia density among families in field populations of the mosquito Culex pipiens , and show that densities in ovary and nongonadal tissues of females in the same family are not correlated, suggesting that Wolbachia density is determined by distinct mechanisms in the two tissues. Using introgression analysis between two different strains of the closely related species C. quinquefasciatus , we show that Wolbachia densities in ovary tissues are determined primarily by cytoplasmic genotype, while densities in nongonadal tissues are determined by both cytoplasmic and nuclear genotypes and their epistatic interactions. Quantitative-trait-locus mapping identified two major-effect quantitative-trait loci in the C. quinquefasciatus genome explaining a combined 23% of variance in Wolbachia density, specifically in nongonadal tissues. A better understanding of how Wolbachia density is regulated will provide insights into how Wolbachia density can vary spatiotemporally in insect populations, leading to changes in Wolbachia -mediated phenotypes such as viral pathogen resistance. Copyright © 2017 Emerson, Glaser.

  9. Iron and iron oxide nanoparticles are highly toxic to Culex quinquefasciatus with little non-target effects on larvivorous fishes.

    Science.gov (United States)

    Murugan, Kadarkarai; Dinesh, Devakumar; Nataraj, Devaraj; Subramaniam, Jayapal; Amuthavalli, Pandiyan; Madhavan, Jagannathan; Rajasekar, Aruliah; Rajan, Mariappan; Thiruppathi, Kulandhaivel Palani; Kumar, Suresh; Higuchi, Akon; Nicoletti, Marcello; Benelli, Giovanni

    2018-04-01

    The control of filariasis vectors has been enhanced in several areas, but there are main challenges, including increasing resistance to insecticides and lack of cheap and eco-friendly products. The toxicity of iron (Fe 0 ) and iron oxide (Fe 2 O 3 ) nanoparticles has been scarcely investigated yet. We studied the larvicidal and pupicidal activity of Fe 0 and Fe 2 O 3 nanoparticles against Culex quinquefasciatus. Fe 0 and Fe 2 O 3 nanoparticles produced by green (using a Ficus natalensis aqueous extract) and chemical nanosynthesis, respectively, were analyzed by UV-Vis spectrophotometry, FT-IR spectroscopy, XRD analysis, SEM, and EDX assays. In larvicidal and pupicidal experiments on Cx. quinquefasciatus, LC 50 of Fe 0 nanoparticles ranged from 20.9 (I instar larvae) to 43.7 ppm (pupae) and from 4.5 (I) to 22.1 ppm (pupae) for Fe 2 O 3 nanoparticles synthesized chemically. Furthermore, the predation efficiency of the guppy fish, Poecilia reticulata, after a single treatment with sub-lethal doses of Fe 0 and Fe 2 O 3 nanoparticles was magnified. Overall, this work provides new insights about the toxicity of Fe 0 and Fe 2 O 3 nanoparticles against mosquito vectors; we suggested that green and chemical fabricated nano-iron may be considered to develop novel and effective pesticides.

  10. Multiple insecticide resistances in the disease vector Culex p. quinquefasciatus from Western Indian Ocean.

    Science.gov (United States)

    Pocquet, Nicolas; Milesi, Pascal; Makoundou, Patrick; Unal, Sandra; Zumbo, Betty; Atyame, Célestine; Darriet, Frédéric; Dehecq, Jean-Sébastien; Thiria, Julien; Bheecarry, Ambicadutt; Iyaloo, Diana P; Weill, Mylène; Chandre, Fabrice; Labbé, Pierrick

    2013-01-01

    Several mosquito-borne diseases affect the Western Indian Ocean islands. Culex pipiens quinquefasciatus is one of these vectors and transmits filariasis, Rift Valley and West Nile viruses and the Japanese encephalitis. To limit the impact of these diseases on public health, considerable vector control efforts have been implemented since the 50s, mainly through the use of neurotoxic insecticides belonging to Organochlorines (OC), Organophosphates (OP) and pyrethroids (PYR) families. However, mosquito control failures have been reported on site, and they were probably due to the selection of resistant individuals in response to insecticide exposure. In this study, we used different approaches to establish a first regional assessment of the levels and mechanisms of resistance to various insecticides. Bioassays were used to evaluate resistance to various insecticides, enzyme activity was measured to assess the presence of metabolic resistances through elevated detoxification, and molecular identification of known resistance alleles was investigated to determine the frequency of target-site mutations. These complementary approaches showed that resistance to the most used insecticides families (OC, OP and PYR) is widespread at a regional scale. However, the distribution of the different resistance genes is quite heterogeneous among the islands, some being found at high frequencies everywhere, others being frequent in some islands and absent in others. Moreover, two resistance alleles displayed clinal distributions in Mayotte and La Réunion, probably as a result of a heterogeneous selection due to local treatment practices. These widespread and diverse resistance mechanisms reduce the capacity of resistance management through classical strategies (e.g. insecticide rotation). In case of a disease outbreak, it could undermine the efforts of the vector control services, as only few compounds could be used. It thus becomes urgent to find alternatives to control populations

  11. Multiple insecticide resistances in the disease vector Culex p. quinquefasciatus from Western Indian Ocean.

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    Nicolas Pocquet

    Full Text Available Several mosquito-borne diseases affect the Western Indian Ocean islands. Culex pipiens quinquefasciatus is one of these vectors and transmits filariasis, Rift Valley and West Nile viruses and the Japanese encephalitis. To limit the impact of these diseases on public health, considerable vector control efforts have been implemented since the 50s, mainly through the use of neurotoxic insecticides belonging to Organochlorines (OC, Organophosphates (OP and pyrethroids (PYR families. However, mosquito control failures have been reported on site, and they were probably due to the selection of resistant individuals in response to insecticide exposure. In this study, we used different approaches to establish a first regional assessment of the levels and mechanisms of resistance to various insecticides. Bioassays were used to evaluate resistance to various insecticides, enzyme activity was measured to assess the presence of metabolic resistances through elevated detoxification, and molecular identification of known resistance alleles was investigated to determine the frequency of target-site mutations. These complementary approaches showed that resistance to the most used insecticides families (OC, OP and PYR is widespread at a regional scale. However, the distribution of the different resistance genes is quite heterogeneous among the islands, some being found at high frequencies everywhere, others being frequent in some islands and absent in others. Moreover, two resistance alleles displayed clinal distributions in Mayotte and La Réunion, probably as a result of a heterogeneous selection due to local treatment practices. These widespread and diverse resistance mechanisms reduce the capacity of resistance management through classical strategies (e.g. insecticide rotation. In case of a disease outbreak, it could undermine the efforts of the vector control services, as only few compounds could be used. It thus becomes urgent to find alternatives to

  12. Larvicidal Activity of Essential Oils of Five Apiaceae Taxa and Some of Their Main Constituents Against Culex quinquefasciatus.

    Science.gov (United States)

    Pavela, Roman; Maggi, Filippo; Cianfaglione, Kevin; Bruno, Maurizio; Benelli, Giovanni

    2018-01-01

    Apiaceae are aromatic herbs producing essential oils which are used on an industrial scale for various purposes. Notably, Apiaceae essential oils may replace synthetic insecticides keeping most of their efficacy and avoiding environmental pollution and human poisoning. In the present work, we explored the insecticidal potential of the essential oils from five Apiaceae taxa, namely Sison amomum, Echinophora spinosa, Heracleum sphondylium subsp. sphondylium, Heracleum sphondylium subsp. ternatum, and Trachyspemum ammi, as well as their major constituents (sabinene, p-cymene, terpinolene, myristicin, and thymol), against the filariasis vector Culex quinquefasciatus. For the purpose, the essential oils were obtained by hydrodistillation and their composition was achieved by gas chromatography/mass spectrometry (GC/MS). Their acute toxicity on third instar larvae of C. quinquefasciatus was determined. The two most active essential oils were those from T. ammi fruits and E. spinosa roots, showing LC 50 below 20 μl/l and LD 90 below 50 μl/l. These oils were dominated by the monoterpene phenol thymol and the phenylpropanoid myristicin, respectively, which showed the strongest larvicidal activity (LC 50 of 15.1 and 16.3 μl/l, respectively) among the pure compounds tested. These results showed that Apiaceae may be useful as source of larvicidal compounds to be used for the development of cheap, effective and eco-friendly insecticidal formulations. © 2018 Wiley-VHCA AG, Zurich, Switzerland.

  13. Oviposition Deterrent and Larvicidal and Pupaecidal Activity of Seven Essential Oils and their Major Components against Culex quinquefasciatus Say (Diptera: Culicidae): Synergism–antagonism Effects

    Science.gov (United States)

    Andrade-Ochoa, Sergio; Sánchez-Aldana, Daniela; Chacón-Vargas, Karla Fabiola; Rivera-Chavira, Blanca E.; Camacho, Alejandro D.; Nogueda-Torres, Benjamín

    2018-01-01

    The larvicidal activity of essential oils cinnamon (Cinnamomum verum J. Presl), Mexican lime (Citrus aurantifolia Swingle) cumin (Cuminum cyminum Linnaeus), clove (Syzygium aromaticum (L.) Merr. & L.M.Perry), laurel (Laurus nobilis Linnaeus), Mexican oregano (Lippia berlandieri Schauer) and anise (Pimpinella anisum Linnaeus)) and their major components are tested against larvae and pupae of Culex quinquefasciatus Say. Third instar larvae and pupae are used for determination of lethality and mortality. Essential oils with more than 90% mortality after a 30-min treatment are evaluated at different time intervals. Of the essential oils tested, anise and Mexican oregano are effective against larvae, with a median lethal concentration (LC50) of 4.7 and 6.5 µg/mL, respectively. Anise essential oil and t-anethole are effective against pupae, with LC50 values of 102 and 48.7 µg/mL, respectively. Oregano essential oil and carvacrol also have relevant activities. A kinetic analysis of the larvicidal activity, the oviposition deterrent effect and assays of the effects of the binary mixtures of chemical components are undertaken. Results show that anethole has synergistic effects with other constituents. This same effect is observed for carvacrol and thymol. Limonene shows antagonistic effect with β-pinene. The high larvicidal and pupaecidal activities of essential oils and its components demonstrate that they can be potential substitutes for chemical compounds used in mosquitoes control programs. PMID:29443951

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

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    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.

  15. Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae to Spondweni Virus.

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    Andrew D Haddow

    2016-10-01

    Full Text Available Zika virus (ZIKV has extended its known geographic distribution to the New World and is now responsible for severe clinical complications in a subset of patients. While substantial genetic and vector susceptibility data exist for ZIKV, less is known for the closest related flavivirus, Spondweni virus (SPONV. Both ZIKV and SPONV have been known to circulate in Africa since the mid-1900s, but neither has been genetically characterized by gene and compared in parallel. Furthermore, the susceptibility of peridomestic mosquito species incriminated or suspected in the transmission of ZIKV to SPONV was unknown.In this study, two geographically distinct strains of SPONV were genetically characterized and compared to nine genetically and geographically distinct ZIKV strains. Additionally, the susceptibility of both SPONV strains was determined in three mosquito species. The open reading frame (ORF of the SPONV 1952 Nigerian Chuku strain, exhibited a nucleotide and amino acid identity of 97.8% and 99.2%, respectively, when compared to the SPONV 1954 prototype South African SA Ar 94 strain. The ORF of the SPONV Chuku strain exhibited a nucleotide and amino acid identity that ranged from 68.3% to 69.0% and 74.6% to 75.0%, respectively, when compared to nine geographically and genetically distinct strains of ZIKV. The ORF of the nine African and Asian lineage ZIKV strains exhibited limited nucleotide divergence. Aedes aegypti, Ae. albopictus and Culex quinquefasciatus susceptibility and dissemination was low or non-existent following artificial infectious blood feeding of moderate doses of both SPONV strains.SPONV and ZIKV nucleotide and amino acid divergence coupled with differences in geographic distribution, ecology and vector species support previous reports that these viruses are separate species. Furthermore, the low degree of SPONV infection or dissemination in Ae. albopictus, Ae. aegypti and Cx. quinquefasciatus following exposure to two

  16. Medical Entomology Studies - III. A Revision of the Subgenus Culex in the Oriental Region (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 12, Number 2)

    Science.gov (United States)

    1976-01-01

    Subgroup with quinquefasciatus which is widespread throughout tropical parts of the world, (2) TrifiZatus Subgroup with vegans and hutchinsoni, both...region; torrentium Martini 1925 from the western Palearctic; vegans Wiedemann 1828 from the eastern Pale- arctic; pervigiluns Bergroth 1889, pacificus...discovered when the fauna is thoroughly examined. 2. C ULEX (C ULEX) VAGANS WIEDEMANN (Figs. 4, 5, 14) Culex vegans Wiedemann 1828: 545 (d, 0

  17. Effectivity of Sugar-Apple (Annona squamosa Seed Extract with a Different Length of Storage against Culec quinquefasciatus Larvae

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    Heni Prasetyowati

    2012-06-01

    Full Text Available Synthetic insecticide have been used to control Culex quinquefasciatus, but the prolonged usage of synthetic insecticide has a bad impact on the environment and may caused resistance. Sugar apple’s (Annona squamosa seeds which contain alkaloid can be used as an alternative insecticide that was safe for environment. This research aims is to know the effect of sugar apple’s seeds with different length of storage as C. quinquefasciatus larvacide. This research was an experimental study with a randomized controlled trial group design approach. The test material was an extract of sugar apple’s seeds which have been kept for 0, 1, 2, and 3 week with LC50 (0,47 ppm was used. Each treatment used 25 C. quinquefasciatus larvae from third instar larvae stage and replicated five times. After exposed for 24 hours, dead larvae counted. The result confirmed that the extract of sugar apple’s seeds which has been stored in 0, 1, 2, and 3 week did not showed any significant different on larvae mortality. Extract of sugar apple’s seeds which have been stored in 0, 1, 2, and 3 week have an equal activity as Culex quinquefasciatus larvicide.

  18. West Nile virus infection rates in Culex nigripalpus (Diptera: Culicidae) do not reflect transmission rates in Florida.

    Science.gov (United States)

    Rutledge, C Roxanne; Day, Jonathan F; Lord, Cynthia C; Stark, Lillian M; Tabachnick, Walter J

    2003-05-01

    We describe the first documented field transmission of West Nile (WN) virus by a North American mosquito. WN was first detected in northern Florida in 2001. An intensive mosquito trapping and surveillance program was conducted in this region for four nights to assess mosquito transmission of WN. Four mosquito traps, each with a single sentinel chicken, were placed at five different locations on each of four nights. A total of 11,948 mosquitoes was collected, and 14 mosquito pools were found to contain WN, giving a minimum infection rate between 1.08 and 7.54 per 1,000. Only one of the 80 sentinel chickens seroconverted to WN, demonstrating a single mosquito transmission event during the study and a mosquito transmission rate of between 0.8 and 1 per 1,000. Culex nigripalpus Theobald was responsible for WN transmission to the sentinel chicken, although both Cx. nigripalpus and Culex quinquefasciatus Say were found infected with WN. Mosquito transmission rates are reported in this study for the first time for a WN outbreak. This information is essential to determine risk of human and animal infection.

  19. EFICACIA DEL BACILLUS SPHAERICUS 2362 EN EL CONTROL DE LARVAS DE ANOPHELES PSUDOPUNCTIPENNIS (THEOBALD, 1901 Y CULEX QUINQUEFASCIATUS (SAY, 1823 EN BIOENSAYO DE LABORATORIO

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    Diana Nongrados

    2014-06-01

    Full Text Available Se probó la actividad del Bacillus sphaericus 2362 en formulación líquida contra larvas de Anopheles pseudopunctipennis (Theobald, 1901 y Culex quinquefasciatus (Say, 1823 en bioensayos de laboratorio. Se utilizó agua destilada y agua de criadero, con concentraciones de 1 x 10 11, 1,5 x 10 11, 2,5 x 10 11, 3,9 x 10 11 esporas/mL. La población blanco se mantuvo en condiciones de laboratorio, usándose agua y flora nativa de criadero. Se vertieron dosis de 1 mL en vasos de prueba que contenían 25 larvas del II y III estadio y 150 mL de agua de criadero o agua destilada respectivamente; se usaron vasos con igual cantidad de agua y larvas como controles para cada concentración, tipo de agua y especie de larva probada. Las pruebas fueron realizadas tres veces para cada concentración, en condiciones de laboratorio. Se realizaron 12 réplicas divididas en 6 para cada especie, usándose un total de 4,800 larvas por especie. Las lecturas de la mortalidad de larvas fueron a las 12, 24, 48 y 72 h después de añadido Bacillus sphaericus. Se observó la elevada susceptibilidad de Culex quinquefasciatus a Bacillus sphaericus 2362, con una mortalidad mayor al 90% cuando se compararon los grupos tratados y controles (valor de p = 0,031 y 0,012 para cada tipo de agua respectivamente a las 48 h y con una concentración de 1,5 x 10 11 esporas/mL. Se demostró ampliamente que Anopheles pseudopunctipennis no es susceptible a Bacillus sphaericus 2362 en bioensayos de laboratorio y no se encontraron diferencias significativas en los tratamientos con diferentes tipos de agua (valor de p > 0,05.

  20. The Influence of Fatty Acid Methyl Esters (FAMEs) in the Biochemistry and the Na(+)/K(+)-ATPase Activity of Culex quinquefasciatus Larvae.

    Science.gov (United States)

    Silva, Lilian N D; Ribeiro-Neto, José A; Valadares, Jéssica M M; Costa, Mariana M; Lima, Luciana A R S; Grillo, Luciano A M; Cortes, Vanessa F; Santos, Herica L; Alves, Stênio N; Barbosa, Leandro A

    2016-08-01

    Culex quinquefasciatus is the main vector of lymphatic filariasis and combating this insect is of great importance to public health. There are reports of insects that are resistant to the products currently used to control this vector, and therefore, the search for new products has increased. In the present study, we have evaluated the effects of fatty acid methyl esters (FAMEs) that showed larvicidal activity against C. quinquefasciatus, on glucose, total protein, and triacylglycerol contents and Na(+)/K(+)-ATPase activity in mosquito larvae. The exposure of the fourth instar larvae to the compounds caused a decrease in the total protein content and an increase in the activity of the Na(+)/K(+)-ATPase. Furthermore, the direct effect of FAMEs on cell membrane was assessed on purified pig kidney Na(+)/K(+)-ATPase membranes, erythrocyte ghost membranes, and larvae membrane preparation. No modifications on total phospholipids and cholesterol content were found after FAMEs 20 min treatment on larvae membrane preparation, but only 360 µg/mL FAME 2 was able to decrease total phospholipid of erythrocyte ghost membrane. Moreover, only 60 and 360 µg/mL FAME 3 caused an activation of purified Na(+)/K(+)-ATPase, that was an opposite effect of FAMEs treatment in larvae membrane preparation, and caused an inhibition of the pump activity. These data together suggest that maybe FAMEs can modulate the Na(+)/K(+)-ATPase on intact larvae for such mechanisms and not for a direct effect, one time that the direct effect of FAMEs in membrane preparation decreased the activity of Na(+)/K(+)-ATPase. The biochemical changes caused by the compounds were significant and may negatively influence the development and survival of C. quinquefasciatus larvae.

  1. Spatio-Temporal Distribution of Vector-Host Contact (VHC) Ratios and Ecological Niche Modeling of the West Nile Virus Mosquito Vector, Culex quinquefasciatus, in the City of New Orleans, LA, USA.

    Science.gov (United States)

    Sallam, Mohamed F; Michaels, Sarah R; Riegel, Claudia; Pereira, Roberto M; Zipperer, Wayne; Lockaby, B Graeme; Koehler, Philip G

    2017-08-08

    The consistent sporadic transmission of West Nile Virus (WNV) in the city of New Orleans justifies the need for distribution risk maps highlighting human risk of mosquito bites. We modeled the influence of biophysical and socioeconomic metrics on the spatio-temporal distributions of presence/vector-host contact (VHC) ratios of WNV vector, Culex quinquefasciatus , within their flight range . Biophysical and socioeconomic data were extracted within 5-km buffer radii around sampling localities of gravid female Culex quinquefasciatus . The spatio-temporal correlations between VHC data and 33 variables, including climate, land use-land cover (LULC), socioeconomic, and land surface terrain were analyzed using stepwise linear regression models (RM). Using MaxEnt, we developed a distribution model using the correlated predicting variables. Only 12 factors showed significant correlations with spatial distribution of VHC ratios ( R ² = 81.62, p < 0.01). Non-forested wetland (NFWL), tree density (TD) and residential-urban (RU) settings demonstrated the strongest relationship. The VHC ratios showed monthly environmental resilience in terms of number and type of influential factors. The highest prediction power of RU and other urban and built up land (OUBL), was demonstrated during May-August. This association was positively correlated with the onset of the mosquito WNV infection rate during June. These findings were confirmed by the Jackknife analysis in MaxEnt and independently collected field validation points. The spatial and temporal correlations of VHC ratios and their response to the predicting variables are discussed.

  2. Efficacy of agnique (mmf) monomolecular surface film against immature stages of Anopheles arabiensis patton and Culex spp (diptera: culicidae) in Khartoum, Sudan.

    Science.gov (United States)

    Bashir, Al; Hassan, A Abu; Salmah, M R Che; Rahman, W A

    2008-03-01

    The efficacy of the larvicidal and pupicidal agent (Agnique) MMF was evaluated against larvae of An. arabiensis and Culex (Diptera: Culicidae) under field conditions in Bahary Locality, Khartoum, Sudan. At an applied dosage of 0.25 ml/m2, MMF resulted in 89.4, 79.8 and 88.2% reductions in L3-L4 instars An. arabiensis and 63.5% in Culex larvae (all stages) 24 to 72 hours post-treatment. Pupae were completely eliminated (100%) within 24 hours posttreatment. The earlier instars (L1-L2) of An. arabiensis were more tolerant with a 62.5% reduction at 72 hours post-treatment compared to (L3-L4) instars and pupae. At 7-days post-treatment Agnique gave a 57.5% reduction in L1-L2 and 92.6% in L3-L4 instar larvae of An. arabiensis and 57.3% and 86.4% in Culex larvae and pupae, respectively. We conclude that Agnique can perform effectively against L3-L4 instars and pupae of An. arabiensis for only 1 week, and 3 to 4 days against L1-L2 instars of Culex spp.

  3. Evaluation of larvicidal activity of Acalypha alnifolia Klein ex Willd. (Euphorbiaceae) leaf extract against the malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Kovendan, Kalimuthu; Murugan, Kadarkarai; Vincent, Savariar

    2012-02-01

    The leaf extract of Acalypha alnifolia with different solvents - hexane, chloroform, ethyl acetate, acetone and methanol - were tested for larvicidal activity against three important mosquitoes such as malarial vector, Anopheles stephensi, dengue vector, Aedes aegypti and Bancroftian filariasis vector, Culex quinquefasciatus. The medicinal plants were collected from the area around Kallar Hills near the Western Ghats, Coimbatore, India. A. alnifolia plant was washed with tap water and shade dried at room temperature. The dried leaves were powdered mechanically using commercial electrical stainless steel blender. The powder 800 g of the leaf material was extract with 2.5 litre of various each organic solvents such as hexane, chloroform, ethyl acetate, acetone, methanol for 8 h using Soxhlet apparatus, and filtered. The crude plant extracts were evaporated to dryness in a rotary vacuum evaporator. The yield of extracts was hexane (8.64 g), chloroform (10.74 g), ethyl acetate (9.14 g), acetone (10.02 g), and methanol (11.43 g). One gram of the each plant residue was dissolved separately in 100 ml of acetone (stock solution) from which different concentrations, i.e., 50, 150, 250, 350 and 450 ppm, was prepared. The hexane, chloroform, ethyl acetate, acetone was moderate considerable mortality; however, the highest larval mortality was methanolic extract observed in three mosquito vectors. The larval mortality was observed after 24 h exposure. No mortality was observed in the control. The early fourth-instar larvae of A. stephensi had values of LC(50) = 197.37, 178.75, 164.34, 149.90 and 125.73 ppm and LC(90) = 477.60, 459.21, 435.07, 416.20 and 395.50 ppm, respectively. The A. aegypti had values of LC(50) = 202.15, 182.58, 160.35, 146.07 and 128.55 ppm and LC(90) = 476.57, 460.83, 440.78, 415.38 and 381.67 ppm, respectively. The C. quinquefasciatus had values of LC(50) = 198.79, 172.48, 151.06, 140.69 and 127.98 ppm and LC(90) = 458.73, 430

  4. Preliminary screening of plant essential oils against larvae of Culex ...

    African Journals Online (AJOL)

    Preliminary screenings of 22 plant essential oils were tested for mortality of the mosquito larvae Culex quinquefasciatus under laboratory conditions. Percent (%) mortality of the mosquito larvae were obtained for each essential oil. At different exposure periods, viz. 1, 3, 6, 12 and 24 h among the 22 plant oils tested, eight ...

  5. Haematophageous vector monitoring in Djibouti city from 2008 to 2009: first records of Culex pipiens ssp. torridus (IGLISCH), and Anopheles sergentii (theobald).

    Science.gov (United States)

    Faulde, Michael K; Ahmed, Ammar A

    2010-08-01

    The Horn of Africa represents a region formerly known to be highly susceptible to mosquito-borne infectious diseases. In order to monitor and analyze the current presence and threat of vector mosquitoes, continuous and standardized trapping using CDC light traps without an additional CO2-generator has been carried out at six selected monitoring sites located in Djibouti City, from August 2008 until December 2009. An overall of 620 haematophageous Diptera were trapped, 603 (97.3%) were mosquitoes, 10 (1.6%) were sand flies, and 7 (1.1%) were biting midges, respectively. Genus distribution of mosquitoes revealed that 600 (99.5%) were Culex spp., 2 (0.3%) were Anopheles sergentii, and 1 (0.2%) was Aedes aegypti. Culex species were represented by Cx. quinquefasciatus (78.5%), and Cx. pipiens ssp. torridus (21.5%). The later species was first detected focally in early December 2009 showing a strongly increasing population density resulting in a maximum trap rate of 25 mosquitoes per trap night. Sand flies were all Sergentomyia antennata, and biting midges of the genus Culicoides were represented by C. nubeculosus (71.4%) and C. vexans (28.6 %). The findings included the first records for Cx. pipiens ssp. torridus and An. sergentii in Djibouti. However, none of the captured female Culex spp, the known vector for West Nile Virus, showed positive results for viral nucleic acids using WNV RT-real time PCR system. Also, females An. sergentii were Plasmodium falciparum and P. vivax circumsporozoite protein negative.

  6. Impact of climate change on filarial vector, Culex quinquefasciatus and control using bacterial pesticide, spinosad

    Directory of Open Access Journals (Sweden)

    Nareshkumar Arjunan

    2014-02-01

    Full Text Available Objective: To show the effect of temperature on the biology of Culex quinquefasciatus and also to show the effect of the bacterial pesticide, spinosad on developmental stages of the filarial vector. Methods: A laboratory colony of mosquito larvae was used for the larvicidal activity of temperature and spinosad. Twenty-five numbers of first, second, third, fourth instar larvae were introduced into the 500 mL glass beaker containing 250 mL of de-chlorinated water with desired temperatures (16 °C, 20 °C, 24 °C, 28 °C, 32 °C, 36 °C, similarly spinosad, at different concentrations. The development was observed for every 24 h. Results: The results showed that the rise in temperature acts as a growth inhibiting factor for mosquitoes. And no development was found in the temperature below 16 °C and above 36 °C. The hatchability was increased as the temperature was increased up to 32 °C, after which eclosion rates dropped gradually. Conclusions: 32 °C was obtained as the maximum sustainable temperature and after which the developmental rate was gradually reduced. The optimal temperature for development was lower than the temperatures at which development was quickest. The bacterial pesticide spinosad showed that it is an effective mosquito control agent and can be used for further integrated pest management programmes.

  7. Effectivity of Sugar-Apple (Annona squamosa) Seed Extract with a Different Length of Storage against Culec quinquefasciatus Larvae

    OpenAIRE

    Heni Prasetyowati; Wisnu Satria

    2012-01-01

    Synthetic insecticide have been used to control Culex quinquefasciatus, but the prolonged usage of synthetic insecticide has a bad impact on the environment and may caused resistance. Sugar apple’s (Annona squamosa) seeds which contain alkaloid can be used as an alternative insecticide that was safe for environment. This research aims is to know the effect of sugar apple’s seeds with different length of storage as C. quinquefasciatus larvacide. This research was an experimental study with a r...

  8. Polymeric nanoencapsulation of insect repellent: Evaluation of its bioefficacy on Culex quinquefasciatus mosquito population and effective impregnation onto cotton fabrics for insect repellent clothing

    Directory of Open Access Journals (Sweden)

    A.P.B. Balaji

    2017-10-01

    Full Text Available Diethylphenylacetamide (Bulk-DEPA, an organic insect repellent was subjected to Poly(ethylene glycol (PEG polymerization followed by Phase Inversion Temperature (PIT emulsification method to yield the polymeric nanodroplets of DEPA (Nano-DEPA. The mean hydrodynamic diameter was found to be 149 ± 1.06 nm. The efficacy of Bulk-DEPA and Nano-DEPA was comparatively investigated on the Culex quinquefasciatus mosquito population. The larvicidal bioassay was performed on the 1st, 2nd, and 3rd instar larvae of Culex quinquefasciatus and the median lethal indices (LC50 of was found to be 0.055, 0.208, 1.397 mg/L and 0.023, 0.144, 0.260 mg/L for Bulk-DEPA and Nano-DEPA respectively. The histopathological studies were found to be corroborative with the larvicidal bioassay. The median knockdown indices (KD50 on 2–3 day old sucrose fed adult mosquitoes determined by WHO cone bioassay and was found to be 55.168 and 33.277 mg/L for Bulk-DEPA and Nano-DEPA. The obtained results indicate the improved efficacy possessed by the Nano-DEPA as comparative to Bulk-DEPA even at lower concentrations. Further, the Nano-DEPA was impregnated onto the alginate cross-linked (ACL and Plain (PL cotton fabrics, and the Washing resistance index (WRI was determined. The obtained results indicate the higher WRI possessed by the ACL cotton fabric than the PL cotton fabric. This was owing to the effective physical entrapment of Nano-DEPA onto the alginate matrices, which was further substantiated by high-resolution scanning electron microscopic (HR-SEM studies. Overall, the present study has emphasized the benefit of formulating Bulk-DEPA into Nano-DEPA to exert higher efficacy on the mosquito population. In addition, study has provided the methodology for the effective impregnation of Nano-DEPA onto the cotton fabrics for the reliable application in long lasting insect repellent clothing.

  9. Olyset Duo® (a pyriproxyfen and permethrin mixture net: an experimental hut trial against pyrethroid resistant Anopheles gambiae and Culex quinquefasciatus in Southern Benin.

    Directory of Open Access Journals (Sweden)

    Corine Ngufor

    Full Text Available Alternative compounds which can complement pyrethroids on long-lasting insecticidal nets (LN in the control of pyrethroid resistant malaria vectors are urgently needed. Pyriproxyfen (PPF, an insect growth regulator, reduces the fecundity and fertility of adult female mosquitoes. LNs containing a mixture of pyriproxyfen and pyrethroid could provide personal protection through the pyrethroid component and reduce vector abundance in the next generation through the sterilizing effect of pyriproxyfen.The efficacy of Olyset Duo, a newly developed mixture LN containing pyriproxyfen and permethrin, was evaluated in experimental huts in southern Benin against pyrethroid resistant Anopheles gambiae and Culex quinquefasciatus. Comparison was made with Olyset Net® (permethrin alone and a LN with pyriproxyfen alone (PPF LN. Laboratory tunnel tests were performed to substantiate the findings in the experimental huts.Overall mortality of wild pyrethroid resistant An. gambiae s.s. was significantly higher with Olyset Duo than with Olyset Net (50% vs. 27%, P = 0.01. Olyset DUO was more protective than Olyset Net (71% vs. 3%, P<0.001. The oviposition rate of surviving blood-fed An. gambiae from the control hut was 37% whereas none of those from Olyset Duo and PPF LN huts laid eggs. The tunnel test results were consistent with the experimental hut results. Olyset Duo was more protective than Olyset Net in the huts against wild pyrethroid resistant Cx. quinquefasciatus although mortality rates of this species did not differ significantly between Olyset Net and Olyset Duo. There was no sterilizing effect on surviving blood-fed Cx. quinquefasciatus with the PPF-treated nets.Olyset Duo was superior to Olyset Net in terms of personal protection and killing of pyrethroid resistant An. gambiae, and sterilized surviving blood-fed mosquitoes. Mixing pyrethroid and pyriproxyfen on a LN shows potential for malaria control and management of pyrethroid resistant vectors by

  10. The Mosquitoes of the Subgenus Culex in Southwestern Asia and Egypt (Diptera: Culicidae) (Contributions of the American Entomological Institute. Volume 24, Number 1, 1988)

    Science.gov (United States)

    1988-01-01

    Pathol. Exot. 53: 531-542. 1968. Contribution a I’etude des moustiques du Maroc (Diptera, Culicidae) six especes nouvelles pour le pays. Cah. ORSTOM...quelques moustiques du Maroc. Arch. inst. Pasteur Maroc 2: 361-365. 1957. Sur Culex torrentium Martini. Ann. Parasitol. Hum. Comp. 32: 438-442...De Grandpre, A.D. and D. D’E. De Charmoy 1900(1901). Les moustiques : anatomie et biologie. Contribution a I’etude des Culicides et principalement

  11. Global spread and genetic variants of the two CYP9M10 haplotype forms associated with insecticide resistance in Culex quinquefasciatus Say.

    Science.gov (United States)

    Itokawa, K; Komagata, O; Kasai, S; Kawada, H; Mwatele, C; Dida, G O; Njenga, S M; Mwandawiro, C; Tomita, T

    2013-09-01

    Insecticide resistance develops as a genetic factor (allele) conferring lower susceptibility to insecticides proliferates within a target insect population under strong positive selection. Intriguingly, a resistance allele pre-existing in a population often bears a series of further adaptive allelic variants through new mutations. This phenomenon occasionally results in replacement of the predominating resistance allele by fitter new derivatives, and consequently, development of greater resistance at the population level. The overexpression of the cytochrome P450 gene CYP9M10 is associated with pyrethroid resistance in the southern house mosquito Culex quinquefasciatus. Previously, we have found two genealogically related overexpressing CYP9M10 haplotypes, which differ in gene copy number (duplicated and non-duplicated). The duplicated haplotype was derived from the non-duplicated overproducer probably recently. In the present study, we investigated allelic series of CYP9M10 involved in three C. quinquefasciatus laboratory colonies recently collected from three different localities. Duplicated and non-duplicated overproducing haplotypes coexisted in African and Asian colonies indicating a global distribution of both haplotype lineages. The duplicated haplotypes both in the Asian and African colonies were associated with higher expression levels and stronger resistance than non-duplicated overproducing haplotypes. There were slight variation in expression level among the non-duplicated overproducing haplotypes. The nucleotide sequences in coding and upstream regions among members of this group also showed a little diversity. Non-duplicated overproducing haplotypes with relatively higher expression were genealogically closer to the duplicated haplotypes than the other non-duplicated overproducing haplotypes, suggesting multiple cis-acting mutations before duplication.

  12. The entomopathogenic fungus Beauveria bassiana reduces instantaneous blood feeding in wild multi-insecticide-resistant Culex quinquefasciatus mosquitoes in Benin, West Africa

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    Howard Annabel FV

    2010-09-01

    Full Text Available Abstract Background Mosquito-borne diseases are still a major health risk in many developing countries, and the emergence of multi-insecticide-resistant mosquitoes is threatening the future of vector control. Therefore, new tools that can manage resistant mosquitoes are required. Laboratory studies show that entomopathogenic fungi can kill insecticide-resistant malaria vectors but this needs to be verified in the field. Methods The present study investigated whether these fungi will be effective at infecting, killing and/or modifying the behaviour of wild multi-insecticide-resistant West African mosquitoes. The entomopathogenic fungi Metarhizium anisopliae and Beauveria bassiana were separately applied to white polyester window netting and used in combination with either a permethrin-treated or untreated bednet in an experimental hut trial. Untreated nets were used because we wanted to test the effect of fungus alone and in combination with an insecticide to examine any potential additive or synergistic effects. Results In total, 1125 female mosquitoes were collected during the hut trial, mainly Culex quinquefasciatus Say. Unfortunately, not enough wild Anopheles gambiae Giles were collected to allow the effect the fungi may have on this malaria vector to be analysed. None of the treatment combinations caused significantly increased mortality of Cx. quinquefasciatus when compared to the control hut. The only significant behaviour modification found was a reduction in blood feeding by Cx. quinquefasciatus, caused by the permethrin and B. bassiana treatments, although no additive effect was seen in the B. bassiana and permethrin combination treatment. Beauveria bassiana did not repel blood foraging mosquitoes either in the laboratory or field. Conclusions This is the first time that an entomopathogenic fungus has been shown to reduce blood feeding of wild mosquitoes. This behaviour modification indicates that B. bassiana could potentially be a new

  13. Estudio comparativo de métodos de extracción, en la obtención de extractos promisorios con actividad larvicida contra el mosquito Culex quinquefasciatus, a partir de residuos frutícolas

    OpenAIRE

    Ortega Barbosa, Jenny Paola

    2014-01-01

    Un total de 23 residuos entre semillas y epicarpios de frutas tropicales, fueron sometidos a extracción Soxhlet a presión reducida con metanol. Con los extractos obtenidos se realizó el tamizaje respecto a la actividad larvicida, contra Culex quinquefasciatus. Se definió como biomasa más promisoria al cáliz de uchuva (Physalis peruviana), cuyo extracto presentó un CL50= 395,6 ppm en 24 h (6,8% de rendimiento). Dicha biomasa fue sometida a extracción con fluidos supercríticos (CO2 a 40°C, 200 ...

  14. Larvicidal effect of aqueous and ethanolic extracts of Senna alata on Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti.

    Science.gov (United States)

    Edwin, Ubulom Peace Mayen; Nyiutaha, Imandeh Godwin; Essien, Akpabio Eno; Nnamdi, Opara Kenneth; Sunday, Ekanem Mfon

    2013-05-01

    Senna alata is locally used in South Eastern Nigeria in the treatment of several infections which include ringworm and other parasitic skin diseases.The larvicidal activities of aqueous and ethanolic leaf and stem extracts of S. alata were evaluated in static bioassays, on fourth instar larvae of Anopheles gambiae, Culex quinquefasciatus and Aedes aegypti, at extract concentrations of 0.15, 0.30, 0.45, 0.60 and 0.75% w/v, for 72 hours. Mortality of larvae exposed to the different extracts increased with increase in extract concentration and time of exposure. This study revealed a differential potency of the extracts used and a difference in susceptibility of larvae to the extracts as evident by the 72hLC₅₀ values obtained. The leaf extract proved to be more lethal to the larvae than the stem extract as judged by the 72hLC₅₀ values obtained both for the aqueous as well as the ethanolic extracts assayed. Phytochemical screening of the plant parts investigated revealed the presence of some plant metabolites, which have been reported in separate studies to be lethal to mosquito larvae. Results obtained from this study suggest that the leaf and stem extracts of S. alata possess a promising larvicidal potential which can be exploited in mosquito vector control.

  15. Regulation of P450-mediated permethrin resistance in Culex quinquefasciatus by the GPCR/Gαs/AC/cAMP/PKA signaling cascade.

    Science.gov (United States)

    Li, Ting; Liu, Nannan

    2017-12-01

    This study explores the role of G-protein-coupled receptor-intracellular signaling in the development of P450-mediated insecticide resistance in mosquitoes, Culex quinquefasciatus , focusing on the essential function of the GPCRs and their downstream effectors of Gs alpha subunit protein (Gαs) and adenylyl cyclase (ACs) in P450-mediated insecticide resistance of Culex mosquitoes. Our RNAi-mediated functional study showed that knockdown of Gαs caused the decreased expression of the downstream effectors of ACs and PKAs in the GPCR signaling pathway and resistance P450 genes, whereas knockdown of ACs decreased the expression of PKAs and resistance P450 genes. Knockdown of either Gαs or ACs resulted in an increased susceptibility of mosquitoes to permethrin. These results add significantly to our understanding of the molecular basis of resistance P450 gene regulation through GPCR/Gαs/AC/cAMP-PKA signaling pathways in the insecticide resistance of mosquitoes. The temporal and spatial dynamic analyses of GPCRs, Gαs, ACs, PKAs, and P450s in two insecticide resistant mosquito strains revealed that all the GPCR signaling pathway components tested, namely GPCRs, Gαs, ACs and PKAs, were most highly expressed in the brain for both resistant strains, suggesting the role played by these genes in signaling transduction and regulation. The resistance P450 genes were mainly expressed in the brain, midgut and malpighian tubules (MTs), suggesting their critical function in the central nervous system and importance for detoxification. The temporal dynamics analysis for the gene expression showed a diverse expression profile during mosquito development, indicating their initially functional importance in response to exposure to insecticides during their life stages.

  16. "Bird biting" mosquitoes and human disease: a review of the role of Culex pipiens complex mosquitoes in epidemiology.

    Science.gov (United States)

    Farajollahi, Ary; Fonseca, Dina M; Kramer, Laura D; Marm Kilpatrick, A

    2011-10-01

    The transmission of vector-borne pathogens is greatly influenced by the ecology of their vector, which is in turn shaped by genetic ancestry, the environment, and the hosts that are fed on. One group of vectors, the mosquitoes in the Culex pipiens complex, play key roles in the transmission of a range of pathogens including several viruses such as West Nile and St. Louis encephalitis viruses, avian malaria (Plasmodium spp.), and filarial worms. The Cx. pipiens complex includes Culex pipiens pipiens with two forms, pipiens and molestus, Culex pipiens pallens, Culex quinquefasciatus, Culex australicus, and Culex globocoxitus. While several members of the complex have limited geographic distributions, Cx. pipienspipiens and Cx. quinquefasciatus are found in all known urban and sub-urban temperate and tropical regions, respectively, across the world, where they are often principal disease vectors. In addition, hybrids are common in areas of overlap. Although gaps in our knowledge still remain, the advent of genetic tools has greatly enhanced our understanding of the history of speciation, domestication, dispersal, and hybridization. We review the taxonomy, genetics, evolution, behavior, and ecology of members of the Cx. pipiens complex and their role in the transmission of medically important pathogens. The adaptation of Cx. pipiens complex mosquitoes to human-altered environments led to their global distribution through dispersal via humans and, combined with their mixed feeding patterns on birds and mammals (including humans), increased the transmission of several avian pathogens to humans. We highlight several unanswered questions that will increase our ability to control diseases transmitted by these mosquitoes. Copyright © 2011 Elsevier B.V. All rights reserved.

  17. Urban mosquito species (Diptera: Culicidae) of dengue endemic communities in the Greater Puntarenas area, Costa Rica.

    Science.gov (United States)

    Calderón-Arguedas, Olger; Troyo, Adriana; Solano, Mayra E; Avendaño, Adrián; Beier, John C

    2009-12-01

    Field studies were conducted to determine the mosquito species richness in the urban area of Greater Puntarenas in Costa Rica. Two cross-sectional entomological surveys were performed in seven localities of Puntarenas: one survey was performed during the wet season and the other during the dry season. The sections evaluated were determined by applying a stratified cluster sampling method using satellite imagery, and a sample of 26 cells (100 x 100m) was selected for the study. The number of cells per locality was proportional to the area of each locality. The presence of mosquito larvae and pupae in water-filled artificial and natural containers was determined in each cell. Infestation was expressed as a diversity index per type of container (Ii). Eight types of larvae were identified (Aedes aegypti, Culex quinquefasciatus, Culex interrogator, Culex nigripalpus, Culex corniger, Culex tarsalis, Limatus durhamii and Toxorhynchites theobaldi) and in two cases it was only possible to identify the genus (Culex sp. and Uranotaenia sp.). A. aegypti was the most common species followed by C. quinquefascitus. Diversity of wet environments can explain the co-occurrence of various culicid species in some localities. Although A. aegypti is the only documented disease vector in the area, C quinquefasciatus, C nigripalpus, and the other species of Culex could be considered potential vectors of other pathogens. The presence and ecology of all mosquito species should be studied to optimize surveillance and prevention of dengue and to prevent the emergence of other mosquito-transmitted diseases.

  18. Deteksi Brugia malayi pada Armigeres subalbatus dan Culex quinquefasciatusyang diinfeksikan darah penderita filariasis dengan metode PCR

    Directory of Open Access Journals (Sweden)

    Yahya Yahya

    2015-01-01

    Full Text Available Abstract. Pemayungdistricts, Batanghari regency of Jambi province classified as filariasis endemic areas in Jambi province since the Mf rate reached 1.5% in 2011. A study was conducted to identify Brugia malayi on experimentally infected Ar. subalbatus and Cx. quinquefasciatus. An experimental study was performed with completely randomized design and six repetitions. Standard of treatment in this study was time (hours that selected for mosquitoes to bite the patients with filariasis (experimental infection. Selected time is at 9.00 a.m, 5.00 p.m, 9.00 p.m, and at 1.00 a.m. The results showed that filarial L3 larvae did not found on Ar. subalbatus and Cx. quinquefasciatus mosquitoes during surgery at day 11th to 13th after infection. Density of microfilariae in the blood of humans as a source of infection was 17 microfilariae per 20 micro liter blood. Otherwise, after detection by PCR, our study found positive B.malayi on Cx. quinquefasciatus thorax and proboscis. It indicates that Cx. quinquefasciatusas potential vector of B.malayi filariasis compared to Ar. subalbatus. Keywords: PCR, filariasis, Armigeres subalbatus, Culex quinquefasciatus, Brugia malayi   Abstrak. Kecamatan Pemayung Kabupaten Batanghari Provinsi Jambi merupakan wilayah endemis filariasis di Provinsi Jambi Karena angka Mf rate mencapai 1,5% pada tahun 2011. Penelitian ini untuk mengetahui tingkat kerentanan nyamuk Ar. subalbatus dan Cx. quinquefasciatus terhadap infeksi B. malayi subperiodik nokturna yang dilakukan pada tahun 2013, sehingga dapat dianalisis potensi nyamuk tersebut sebagai vektor filariasis di lokasi penelitian. Desain penelitian adalah eksperimental dengan rancangan acak lengkap dan enam kali pengulangan. Variabel perlakuan dalam penelitian ini adalah waktu (jam yang dipilih untuk menggigitkan nyamuk pada penderita filariasis (infeksi percobaan. Waktu yang dipilih adalah pukul 09.00 WIB, pukul 17.00 WIB, pukul 21.00 WIB dan pukul 01.00 WIB. Hasil penelitian

  19. Genetic Characterization of Spondweni and Zika Viruses and Susceptibility of Geographically Distinct Strains of Aedes aegypti, Aedes albopictus, and Culex quinquefasciatus (Diptera: Culicidae) to Spondweni Virus

    Science.gov (United States)

    2016-10-26

    301 policy or position of the U.S. Department of Defense, the Department of the Army, 302 Centers for Disease Control and Prevention, or the Kingdom...Aedes albopicutus (Thailand) 12 0 (0.0) 0 (0.0) Aedes albopicutus ( Venezuela ) 3 0 (0.0) 0 (0.0) Culex quinquefaciatus (Galveston, USA) 24 0 (0.0...albopicutus ( Venezuela ) 24 0 (0.0) 0 (0.0) Culex quinquefaciatus (Galveston, USA) 24 0 (0.0) 0 (0.0) 550 551 552 553 554 555 556 557

  20. Susceptibility of a North American Culex quinquefasciatus to Japanese encephalitis virus

    Science.gov (United States)

    Japanese encephalitis virus (JEV) is a flavivirus that is transmitted by Culex (Cx.) tritaeniorhynchus in tropical and subtropical regions of Asia. The endemic transmission cycle involves domestic pigs and avian species that serve as amplification hosts; humans are incidental hosts that cannot devel...

  1. Effects of West Nile virus dose and extrinsic incubation temperature on temporal progression of vector competence in Culex pipiens quinquefasciatus.

    Science.gov (United States)

    Anderson, Sheri L; Richards, Stephanie L; Tabachnick, Walter J; Smartt, Chelsea T

    2010-03-01

    Culex pipiens quinquefasciatus were fed blood containing either 7.0 +/- 0.1 logs plaque-forming units (pfu)/ml (high dose) or 5.9 +/- 0.1 logs pfu/ml (low dose) of West Nile virus and held at extrinsic incubation temperatures (EIT) of 28 degrees C or 25 degrees C. Approximately 20 mosquitoes per dose were collected after incubation periods (IP) of 4, 6, 8, and 12 days postinfection (dpi). Infection rates were influenced by EIT and virus dose but not by IP. Body titer was significantly higher for mosquitoes fed the high dose and held at 28 degrees C at the later IPs (6, 8, and 12 dpi). However, leg titer was significantly higher for mosquitoes at the later IPs but did not differ between EITs or doses. Because infection rates varied with EIT and dose, there is likely a midgut infection barrier influenced by these factors that is not influenced by IP. Dissemination rates were influenced by all 3 factors consistent with the presence of a midgut escape barrier. Dissemination rate, body titer, and leg titer were dependent on IP, indicating the need to investigate multiple time points in vector competence studies to elucidate critical events in infection and dissemination.

  2. Larvicidal, Histopathological Efficacy of Penicillium daleae against Larvae of Culex quinquefasciatus and Aedes aegypti Plus Biotoxicity on Artemia nauplii a Non-target Aquatic Organism

    Directory of Open Access Journals (Sweden)

    C. Ragavendran

    2017-10-01

    Full Text Available Mosquitoes can transmit the terrible diseases to human beings. Soil-borne fungal products act as potential source for low-cost chemicals, used for developing eco-friendly control agents against mosquito-vector borne diseases. The prime aim of study was to check the larvicidal potential of fungus mycelia (by ethyl acetate solvent extract from Penicillium daleae (KX387370 against Culex quinquefasciatus and Aedes aegypti and to test the toxicity of brine shrimp Artemia nauplii, by observing the physiological activity. The ethyl acetate extract of P. daleae mycelia (after 15 days from Potato dextrose broth (PDB medium revealed better result with least LC50 and LC90 values of I-IV instars larvae of Cx. quinquefasciatus (LC50 = 127.441, 129.087, 108.683, and 93.521; LC90 = 152.758, 158.169, 139.091, and 125.918 μg/ml and Ae. aegypti (LC50 = 105.077, 83.943, 97.158, and 76.513; LC90 = 128.035, 106.869, 125.640, and 104.606 μg/ml respectively. At higher concentration (1000 μg/ml of extracts, mortality begins at 18 h of exposure and attained 100% mortality after 48 h exposure. Overall, the activity was depends on the dose and time of exposure to the extracts. The stereomicroscopic and histopathological analysis of Ae. aegypti and Cx. quinquefasciatus larvae treated with mycelium ethyl acetate extract showed complete disintegration of abdominal region, particularly the midgut and caeca, loss of cuticular parts and caudal hairs. Morphological characterization of the fungi was performed and taxonomically identified through 5.8s rDNA technique. The phylogenetic analysis of rDNA sequence was carried out to find out the taxonomic and the evolutionary sketch of isolate in relation to earlier described genus Penicillium. Behavior and swimming speed alteration was analyzed together with mortality. The results of the experiment indicates that swimming behavior recorder (SBR is a appropriate tool to detect individual swimming speed of the A. nauplii organisms

  3. Chemical composition and larvicidal activity of essential oil of Origanum majorana (Lamiaceae) cultivated in Morocco against Culex pipiens (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Fouad El-Akhal; Abdelhakim El Ouali Lalami; Yassine Ez Zoubi; Hassane Greche; Raja Guemmouh

    2014-01-01

    Objective:To evaluate the larvicidal activity of essential oil of Origanum majorana (Lamiaceae) cultivated in Morocco against Culex pipiens (Diptera:Culicidae). Methods: The analysis and the identification of the various constituents of essential oil were carried out by gas chromatography coupled with mass spectrometry. Biological test was performed according to a standard methodology inspired by the World Health Organization protocol with slight modification. Results:This oil mainly consisted of monoterpene and sesquiterpenes. The majority compounds are 4-terpinene (28.96%), γ-terpinene (18.57%), α-terpinene (12.72%) and sabinene (8.02%). The lethal concentrations (LC50 and LC90) measured for the essential oil Origanum majorana, were respectively of the order of 258.71 mg/L and 580.49 mg/L.

  4. Multiple Cytochrome P450 genes: their constitutive overexpression and permethrin induction in insecticide resistant mosquitoes, Culex quinquefasciatus.

    Science.gov (United States)

    Liu, Nannan; Li, Ting; Reid, William R; Yang, Ting; Zhang, Lee

    2011-01-01

    Four cytochrome P450 cDNAs, CYP6AA7, CYP9J40, CYP9J34, and CYP9M10, were isolated from mosquitoes, Culex quinquefasciatus. The P450 gene expression and induction by permethrin were compared for three different mosquito populations bearing different resistance phenotypes, ranging from susceptible (S-Lab), through intermediate (HAmCq(G0), the field parental population) to highly resistant (HAmCq(G8), the 8(th) generation of permethrin selected offspring of HAmCq(G0)). A strong correlation was found for P450 gene expression with the levels of resistance and following permethrin selection at the larval stage of mosquitoes, with the highest expression levels identified in HAmCq(G8), suggesting the importance of CYP6AA7, CYP9J40, CYP9J34, and CYP9M10 in the permethrin resistance of larva mosquitoes. Only CYP6AA7 showed a significant overexpression in HAmCq(G8) adult mosquitoes. Other P450 genes had similar expression levels among the mosquito populations tested, suggesting different P450 genes may be involved in the response to insecticide pressure in different developmental stages. The expression of CYP6AA7, CYP9J34, and CYP9M10 was further induced by permethrin in resistant mosquitoes. Taken together, these results indicate that multiple P450 genes are up-regulated in insecticide resistant mosquitoes through both constitutive overexpression and induction mechanisms, thus increasing the overall expression levels of P450 genes.

  5. Permethrin induction of multiple cytochrome P450 genes in insecticide resistant mosquitoes, Culex quinquefasciatus.

    Science.gov (United States)

    Gong, Youhui; Li, Ting; Zhang, Lee; Gao, Xiwu; Liu, Nannan

    2013-01-01

    The expression of some insect P450 genes can be induced by both exogenous and endogenous compounds and there is evidence to suggest that multiple constitutively overexpressed P450 genes are co-responsible for the development of resistance to permethrin in resistant mosquitoes. This study characterized the permethrin induction profiles of P450 genes known to be constitutively overexpressed in resistant mosquitoes, Culex quinquefasciatus. The gene expression in 7 of the 19 P450 genes CYP325K3v1, CYP4D42v2, CYP9J45, (CYP) CPIJ000926, CYP325G4, CYP4C38, CYP4H40 in the HAmCqG8 strain, increased more than 2-fold after exposure to permethrin at an LC50 concentration (10 ppm) compared to their acetone treated counterpart; no significant differences in the expression of these P450 genes in susceptible S-Lab mosquitoes were observed after permethrin treatment. Eleven of the fourteen P450 genes overexpressed in the MAmCqG6 strain, CYP9M10, CYP6Z12, CYP9J33, CYP9J43, CYP9J34, CYP306A1, CYP6Z15, CYP9J45, CYPPAL1, CYP4C52v1, CYP9J39, were also induced more than doubled after exposure to an LC50 (0.7 ppm) dose of permethrin. No significant induction in P450 gene expression was observed in the susceptible S-Lab mosquitoes after permethrin treatment except for CYP6Z15 and CYP9J39, suggesting that permethrin induction of these two P450 genes are common to both susceptible and resistant mosquitoes while the induction of the others are specific to insecticide resistant mosquitoes. These results demonstrate that multiple P450 genes are co-up-regulated in insecticide resistant mosquitoes through both constitutive overexpression and induction mechanisms, providing additional support for their involvement in the detoxification of insecticides and the development of insecticide resistance.

  6. Urban mosquito species (Diptera: Culicidae of dengue endemic communities in the Greater Puntarenas area, Costa Rica

    Directory of Open Access Journals (Sweden)

    Olger Calderón-Arguedas

    2009-12-01

    Full Text Available Field studies were conducted to determine the mosquito species richness in the urban area of Greater Puntarenas in Costa Rica. Two cross-sectional entomological surveys were performed in seven localities of Puntarenas: one survey was performed during the wet season and the other during the dry season. The sections evaluated were determined by applying a stratified cluster sampling method using satellite imagery, and a sample of 26 cells (100x100m was selected for the study. The number of cells per locality was proportional to the area of each locality. The presence of mosquito larvae and pupae in water-filled artificial and natural containers was determined in each cell. Infestation was expressed as a diversity index per type of container (Ii. Eight types of larvae were identified (Aedes aegypti, Culex quinquefasciatus, Culex interrogator, Culex nigripalpus, Culex corniger, Culex tarsalis, Limatus durhamii and Toxorhynchites theobaldi and in two cases it was only possible to identify the genus (Culex sp. and Uranotaenia sp.. A. aegypti was the most common species followed by C. quinquefascitus. Diversity of wet environments can explain the co-occurrence of various culicid species in some localities. Although A. aegypti is the only documented disease vector in the area, C quinquefasciatus, C. nigripalpus, and the other species of Culex could be considered potential vectors of other pathogens. The presence and ecology of all mosquito species should be studied to optimize surveillance and prevention of dengue and to prevent the emergence of other mosquito-transmitted diseases. Rev. Biol. Trop. 57 (4: 1223-1234. Epub 2009 December 01.La riqueza de especies de mosquitos urbanos de la Gran Puntarenas (Puntarenas, Costa Rica fue evaluada por medio de análisis larvales. Dos encuestas entomológicas fueron realizadas en siete localidades de la Gran Puntarenas durante un año. Una de las encuestas fue realizada en la estación seca y la otra se llevó a

  7. Experimental infection of Hawai'i 'Amakihi (hemignathus virens) with West Nile virus and competence of a co-occurring vector, culex quinquefasciatus: potential impacts on endemic Hawaiian avifauna.

    Science.gov (United States)

    Lapointe, Dennis; Hofmeister, Erik K.; Atkinson, C.T.; Porter, R.E.; Dusek, Robert J.

    2009-01-01

    Introduced mosquito-borne avian disease is a major limiting factor in the recovery and restoration of native Hawaiian forest birds. Annual epizootics of avian pox (Avipoxvirus) and avian malaria (Plasmodium relictum) likely led to the extinction of some species and continue to impact populations of susceptible Hawaiian honeycreepers (Drepanidinae). The introduction of a novel pathogen, such as West Nile virus (WNV), could result in further population declines and extinctions. During September and October 2004, we infected Hawai'i' Amakihi (Hemignathus virens) with a North American isolate of WNV by needle inoculation and mosquito bite to observe susceptibility, mortality, and illness in this endemic passerine, and to determine the vector competence of the co-occurring, introduced mosquito Culex quinquefasciatus. All experimentally infected Hawai'i ;Amakihi became viremic, with a mean titer >10(5) plaque-forming units (PFU)/ml, and they experienced clinical signs ranging from anorexia and lethargy to ataxia. The fatality rate among needle-inoculated Hawai'i' Amakihi (n=16) was 31.3%, but mortality in free-ranging birds is likely to increase due to predation, starvation, thermal stress, and concomitant infections of avian malaria and pox. Surviving Hawai'i' Amakihi seem to clear WNV from the peripheral blood by 7-10 days postinfection (DPI), and neutralizing antibodies were detected from 9 to 46 DPI. In transmission trials, Hawaiian Cx. quinquefasciatus proved to be a competent vector and Hawai'i Amakihi an adequate amplification host of WNV, suggesting that epizootic WNV could readily become an additional limiting factor of some native Hawaiian bird populations.

  8. Field evaluation of the biolarvicide, spinosad 20 per cent emulsifiable concentrate in comparison to its 12 per cent suspension concentrate formulation against Culex quinquefasciatus, the vector of bancroftian filariasis in India.

    Science.gov (United States)

    Sadanandane, Candasamy; Gunasekaran, Kasinathan; Boopathi Doss, Ponnusamy Sivagnana; Jambulingam, Purushothaman

    2018-01-01

    Biolarvicides may offer alternatives to chemical larvicides as these are known to be safe to environment and selective against the target species. However, only a limited number of biolarvicides have been approved for mosquito larval control. In the current study, a new formulation of spinosad, 20 per cent emulsifiable concentrate (EC) was tested for its efficacy against Culex quinquefasciatus, in comparison to its 12 per cent suspension concentrate (SC). Spinosad 20 per cent EC was tested against Cx. quinquefasciatus immature at 25, 50, 100 and 150 mg active ingredient (ai)/m [2] in cesspits, drains and abandoned wells in comparison with spinosad 12 per cent SC at the optimum field application dosage of 50 mg ai/m [2] . The 20 per cent EC caused 90-100 per cent reduction of pupal density for 7-14 days in cesspits, 10-17 days in drains and 14-30 days in abandoned wells at all dosages tested. At lower dosages of 25 and 50 mg ai/m [2] , >90 per cent reduction of pupal density was observed for one week in cesspits and street drains and for two weeks in abandoned wells. The effective duration of control provided by the higher dosages, 100 and 150 mg ai/m [2] was 1.4 to 2 times greater than the lower dosages, 25 and 50 mg ai/m [2] . The findings showed that the spinosad 20 per cent EC can be used for larval control against Cx. quinquefasciatus, at the dosage of 25 mg ai/m [2] at weekly interval in cesspits and drains and at fortnightly interval in abandoned wells. Spinosad 20 per cent EC could be one of the options to be considered for larval control under integrated vector management.

  9. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 10- survey of adult behaviour of Culex nigripalpus and other species of Culex (Culex in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1995-08-01

    Full Text Available A survey of adult behaviour of Culex (Culex species was carried out from August 1992 through December 1993 in a human modified (anthropic environment in the Ribeira Valley, S.Paulo State, Brazil. Culex nigripalpus dominated the catches at several sites and it's tendency to increase in the anthropic environment became quite clear. Nevertheless no high level of synanthropy was demonstrated. So it seems that the mosquito may have a restricted role in natural arbovirus cycles. Nonetheless, Cx. nigripalpus must be considered a potential vector of arboviruses, especially St. Louis encephalitis virus outside dwellings.São relatados os resultados obtidos mediante coletas regulares de adultos de Culex (Culex em ambientes antrópico do Vale do Ribeira, SP, Brasil, no período de agosto de 1992 a dezembro de 1993. Pôde-se evidenciar a dominancia de Culex nigripalpus nas várias coletas efetuadas. Revelou-se claramente a preferência por parte desse mosquito em aumentar sua densidade no ambiente antrópico. Todavia, sua freqüência ao domicílio mostrou-se baixa, revelando fraco grau de sinantropia. Assim sendo, seu papel vetor de arbovirus parece restringir-se à participação no ciclo natural desses agentes infecciosos. Contudo, pode-se considerá-lo como vetor potencial no meio extradomiciliar. Nesse particular, seu papel pode não ser negligenciável, especialmente no que tange à possibilidade de transmissão de encefalite de S.Luís, cujo agente já foi assinalado na região.

  10. Detection of West Nile virus-specific antibodies and nucleic acid in horses and mosquitoes, respectively, in Nuevo Leon State, northern Mexico, 2006-2007.

    Science.gov (United States)

    Ibarra-Juarez, L; Eisen, L; Bolling, B G; Beaty, B J; Blitvich, B J; Sanchez-Casas, R M; Ayala-Sulca, Y O; Fernandez-Salas, I

    2012-09-01

    In the last 5 years, there has been only one reported human case of West Nile virus (WNV) disease in northern Mexico. To determine if the virus was still circulating in this region, equine and entomological surveillance for WNV was conducted in the state of Nuevo Leon in northern Mexico in 2006 and 2007. A total of 203 horses were serologically assayed for antibodies to WNV using an epitope-blocking enzyme-linked immunosorbent assay (bELISA). Seroprevalences for WNV in horses sampled in 2006 and 2007 were 26% and 45%, respectively. Mosquito collections in 2007 produced 7365 specimens representing 15 species. Culex mosquitoes were screened for WNV RNA and other genera (Mansonia, Anopheles, Aedes, Psorophora and Uranotaenia) were screened for flaviviruses using reverse-transcription (RT)-PCR. Two pools consisting of Culex spp. mosquitoes contained WNV RNA. Molecular species identification revealed that neither pool included Culex quinquefasciatus (Say) (Diptera:Culicidae) complex mosquitoes. No evidence of flaviviruses was found in the other mosquito genera examined. These data provide evidence that WNV is currently circulating in northern Mexico and that non-Cx. quinquefasciatus spp. mosquitoes may be participating in the WNV transmission cycle in this region. Published 2012. This article is a U.S. Government work and is in the public domain in the USA.

  11. Vertebrate hosts and phylogenetic relationships of amphibian trypanosomes from a potential invertebrate vector, Culex territans Walker (Diptera: Culicidae).

    Science.gov (United States)

    Bartlett-Healy, Kristen; Crans, Wayne; Gaugler, Randy

    2009-04-01

    The blood meals of field-collected female Culex territans (Diptera: Culicidae) were concurrently assayed for the presence of trypanosomes and for vertebrate host identification. We amplified vertebrate DNA in 42 of 119 females and made positive identification to the host species level in 29 of those samples. Of the 119 field-collected Cx. territans females, 24 were infected with trypanosomes. Phylogenetic analysis placed the trypanosomes in the amphibian portion of the aquatic clade of the Trypanosomatidae. These trypanosomes were isolated from Cx. territans females that had fed on the frog species Rana clamitans, R. catesbeiana, R. virgatipes, and Rana spp. Results support a potential new lineage of dipteran-transmitted amphibian trypanosomes may occur within the aquatic clade. The frequency in which female Cx. territans acquire trypanosomes, through diverse feeding habits, indicates a new relationship between amphibian trypanosomes and mosquitoes that has not been examined previously. Combining Trypanosoma species, invertebrate, and vertebrate hosts to existing phylogenies can elucidate trypanosome and host relationships.

  12. Cis-acting mutation and duplication: History of molecular evolution in a P450 haplotype responsible for insecticide resistance in Culex quinquefasciatus.

    Science.gov (United States)

    Itokawa, Kentaro; Komagata, Osamu; Kasai, Shinji; Masada, Masahiro; Tomita, Takashi

    2011-07-01

    A cytochrome P450 gene, Cyp9m10, is more than 200-fold overexpressed in a pyrethroid resistant strain of Culex quinquefasciatus, JPal-per. The haplotype of this strain contains two copies of Cyp9m10 resulted from recent tandem duplication. In this study, we discovered and isolated a Cyp9m10 haplotype closely related to this duplicated Cyp9m10 haplotype from JHB, a strain used for the recent genome project for this mosquito species. The isolated haplotype (JHB-NIID-B haplotype) shared the same insertion of a transposable element upstream of the coding region with JPal-per strain but not duplicated. The JHB-NIID-B haplotype was considered to have diverged from the JPal-per lineage just before the duplication event. Cyp9m10 was moderately overexpressed in larvae with the JHB-NIID-B haplotype. The overexpressions in JHB-NIID-B and JPal-per haplotypes were developmentally regulated in similar pattern indicating both haplotypes share a common cis-acting mutation responsible for the overexpressions. The isolated moderately overexpressed haplotype conferred resistance, however, its efficacy was relatively small. We hypothesized that the first cis-acting mutation modified the consequence of the subsequent duplication in JPal-per lineage to confer stronger phenotypic effect than that if it occurred before the first cis-acting mutation. Copyright © 2011 Elsevier Ltd. All rights reserved.

  13. Chemical composition and larvicidal activity of essential oil of Origanum majorana(Lamiaceae) cultivated in Morocco against Culex pipiens(Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Fouad; El-Akhal; Abdelhakim; El; Ouali; Lalami; Yassine; Ez; Zoubi; Hassane; Greche; Raja; Guemmouh

    2014-01-01

    Objective:To evaluate the larvicidal activity of essential oil of Origanum mtijoruna(Lamiaceae)cultivated in Morocco against Culex pipiens(Diptera:Culicidae).Methods:The analysis and the identification of the various constituents of essential oil were carried out by gas chromatography coupled with mass spectrometry.Biological test was performed according to a standard methodology inspired by the World Health Organization protocol with slight modification.Results:This oil mainly consisted of monoterpene and sesquiterpenes.The majority compounds are 4-terpinene(28.96%),y-terpinene(18.57%),α-terpinene(12.72%) and sabinene(8.02%).The lethal concentrations(LC50 and LC90) measured for the essential oil Origanum majorana,were respectively of the order of 258.71 mg/L and 580.49 mg/L.Conclusions:The results could be useful in search for newer,safer,and more effective natural larvicidal agents.

  14. Development of lymphatic filarial parasite Wuchereria bancrofti (Spirurida: Onchocercidae) in mosquito species (Diptera: Culicidae) fed artificially on microfilaremic blood.

    Science.gov (United States)

    Paily, K P; Hoti, S L; Balaraman, K

    2006-11-01

    The efficiency of laboratory colonies of mosquitoes such as Anopheles stephensi Liston, Aedes aegypti (L.) Liverpool strain, Ae. aegypti wild type, Aedes albopictus (Skuse), Culex tritaeniorhynchus Giles, Culex sitiens Wiedemann, and Armigeres subalbatus Coquillett in supporting the development of Wuchereria bancrofti (Cobbold) (Spirurida: Onchocercidae) microfilariae to infective larvae was investigated. The mosquitoes were fed on heparinized microfilaremic human blood by using a membrane-feeding unit with Parafilm as membrane. The rate of infection, parasite development, and parasite burden were compared with that in the known vector mosquito Culex quinquefasciatus Say. Cx. quinquefasciatus showed the highest percentage of infection, followed by Ae. aegypti Liverpool strain and An. stephensi. The rate of development of the parasite was more or less similar in all the three species, and infective larvae were found on day 13. When the larvae were harvested on day 17, Cx. quinquefasciatus yielded the highest numbers, followed by Ae. aegypti Liverpool strain and An. stephensi. The percentage of infection was low, and the development was slow in Cx. tritaeniorhynchus compared with the other susceptible species. The parasite developed to second-stage larvae only by day 22 and to infective larvae by day 28. When 2-wk-old Cx. tritaeniorhynchus were fed on microfilaremic blood, they could develop the parasite to infective larvae by day 13 postfeeding. All other species of mosquitoes tested were found to be refractory to parasite development. It is shown that Cx. quinquefasciatus is the most suitable mosquito host for the production of infective larvae. However, Ae. aegypti Liverpool strain, which is commonly used for Brugia malayi filarial parasite, also can be used for generation of W. bancrofti infective larvae to circumvent the problem of maintaining two mosquito species.

  15. Preferencia de hospedadores de Culicidae (Diptera recolectados en el centro de la Argentina Host preference of Culicidae (Diptera collected in central Argentina

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    Walter R. Almirón

    1995-04-01

    Full Text Available Con el propósito de estudiar la preferencia de hospedadores vertebrados por mosquitos hembras, durante 2 períodos octubre-abril (primavera-verano, se realizaron muestreos cada 15 días en Córdoba y Cosquín (Argentina. Se utilizaron trampas de latón con cebo animal: anfibios (sapos, aves (pollos, mamíferos (conejos y reptiles (tortugas. El 92,9% de los especímenes recolectados pertenecen al género Culex, mientras que un 7,0% corresponde a Aedes y el 0,02% restante a Psorophora ciliata, única especie que se capturó de ese género. En trampas con pollo se recolectó el mayor número de hembras (68,7%, siguiendo en orden las trampas con conejos (29,9%, con tortugas (0,8% y con sapos (0,5%, por lo tanto, la mayoría de los mosquitos entraron en las trampas con hospedadores homeotermos. Culex dolosus se alimentó sobre todos los cebos, mientras que Cx. acharistus, Cx. chidesteri y Cx. quinquefasciatus se alimentaron sobre pollos, conejos y tortugas; Ae. albifasciatus, Ae. scapularis, Cx. bidens y Cx. coronator lo hicieron sobre ambos hospedadores homeotermos; Cx. apicinus, Cx. maxi, Cx. saltanensis y Cx. spinosus se alimentaron solamente sobre pollos y Ps. ciliata sobre conejos.Com o propósito de estudar a preferência de mosquitos fêmeas por hospedeiros vertebrados, realizaram-se amostragens quinzenais nas cidades de Córdoba e Cosquín (Argentina, durante o período de outubro a abril (primavera-verão, por dois anos consecutivos. Utilizaram-se armadilhas com iscas animais: anfíbios, aves, mamíferos e répteis. Dos espécimes coletados, 92,9% pertenciam ao gênero Culex, 7,0% a Aedes e 0,02% a Psorophora ciliata, única espécie coletada desse gênero. A maior proporçãoo de fêmeas (68,7% foi capturada em armadilhas iscadas com galinhas, seguindo-se em ordem as armadilhas com coelhos (29,9%, com tartarugas (0,8% e com anfíbios (0,05%. Assim, a maioria dos mosquitos foi coletada em armadilhas com hospedeiros homeotermos. Culex

  16. Trial of spatial repellency of metofluthrin impregnated paper strip against Anopheles and Culex in shelters without walls in Lombok, Indonesia

    OpenAIRE

    Kawada, Hitoshi; Maekawa, Yoshihide; Tsuda, Yoshio; Takagi, Masahiro

    2004-01-01

    TriaIs of metofluthrin-impregnated multilayer paper strips against mosquitoes in shelters with no walls were carried out at 3 sites in Lombok, Indonesia. Major reductions in human biting by Culex quinquefasciatus,Anopheles balabacensis, and An. sundaicus were achieved. The device is a very praitical measure of preventing outdoor mosquito biting, with no need for electricity or heating to evaporate its active ingredient.

  17. Trial of spatial repellency of metofluthrin-impregnated paper strip against Anopheles and Culex in shelters without walls in Lombok, Indonesia.

    Science.gov (United States)

    Kawada, Hitoshi; Maekawa, Yoshihide; Tsuda, Yoshio; Takagi, Masahiro

    2004-12-01

    Trials of metofluthrin-impregnated multilayer paper strips against mosquitoes in shelters with no walls were carried out at 3 sites in Lombok, Indonesia. Major reductions in human biting by Culex quinquefasciatus, Anopheles balabacensis, and An. sundaicus were achieved. The device is a very practical measure of preventing outdoor mosquito biting, with no need for electricity or heating to evaporate its active ingredient.

  18. KOMPOSISI SPESIES DAN DOMINASI NYAMUK CULEX DI DAERAH ENDEMIS FILARIASIS LIMFATIK DI KELURAHAN PABEAN KOTA PEKALONGAN

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    Tri Ramadhani

    2012-11-01

    Full Text Available Filariasis is one of the communicable disease which is caused by infestation of Filaria wonn. The disease is transmitted by various mosquitoes. Pabean village was one of the endemic area in Pekalongan city with lymphatic filariasis problem (microfilariae rate >1 %. The research aimed to get species and dominan potencial vector filariasis and breeding place.The reseach was an observational study which used cross sectional design. The activity were mosquitoes, larve dipper and pupa collection from August until December 2007. The mosquitoes collection was done twice a week by landing collection and light trap with dry ice.The result showed that the species culex mosquitoes found 19.229, consisted of four species that is Cx.quinquefasciatus, Cx.bitaeniorhynchus, Cx. tritaeniorhynchus, and Cx. vishnui. Mosquito of Cx.quinquefasciatus most dominantly found at all of way of arrest and known as mosquito of vector potential of lymphatic filariasis in Pabean village. Especial breeding place of Cx.quinquefasciatus is water polution and very bad sanitation. The larval density was more than 100 of dipper.

  19. Detection of Wolbachia endobacteria in Culex quinquefasciatus by Gimenez staining and confirmation by PCR.

    Science.gov (United States)

    Muniaraj, M; Paramasivan, R; Sunish, I P; Arunachalam, N; Mariappan, T; Jerald Leo, S Victor; Dhananjeyan, K J

    2012-12-01

    Wolbachia are common intracellular bacteria that are found in arthropods and nematodes. These endosymbionts are transmitted vertically through host eggs and alter host biology in diverse ways, including the induction of reproductive manipulations, such as feminization, parthenogenesis, male killing and sperm-egg incompatibility. Since they can also move horizontally across species boundaries, Wolbachia is gaining importance in recent days as it could be used as a biological control agent to control vector mosquitoes or for paratransgenic approaches. However, the study of Wolbachia requires sophisticated techniques such as PCR and cell culture facilities which cannot be affordable for many laboratories where the diseases transmitted by arthropod vectors are common. Hence, it would be beneficial to develop a simple method to detect the presence of Wolbachia in arthropods. In this study, we described a method of staining Wolbachia endobacteria, present in the reproductive tissues of mosquitoes. The reliability of this method was compared with Gram staining and PCR based detection. The microscopic observation of the Gimenez stained smear prepared from the teased ovary of wild caught and Wolbachia (+) Cx. quinquefasciatus revealed the presence of pink coloured pleomorphic cells of Wolbachia ranging from cocci, comma shaped cells to bacillus and chain forms. The ovaries of Wolbachia (-) cured mosquito did not show any cell. Although Gram's staining is a reliable differential staining for the other bacteria, the bacterial cells in the smears from the ovaries of wild caught mosquitoes did not take the stain properly and the cells were not clearly visible. The PCR amplified product from the pooled remains of wild caught and Wolbachia (+) Cx. quinquefasciatus showed clear banding, whereas, no banding was observed for the negative control (distilled water) and Wolbachia (-) Cx. quinquefasciatus. The Gimenez staining technique applied, could be used to detect the members of

  20. Mammalophilic feeding behaviour of Culex quinquefasciatus mosquitoes collected in the cities of Chetumal and Cancun, Yucatán Peninsula, Mexico.

    Science.gov (United States)

    Janssen, Nele; Fernandez-Salas, Ildefonso; Díaz González, Esteban Eduardo; Gaytan-Burns, Alejandro; Medina-de la Garza, Carlos E; Sanchez-Casas, Rosa María; Börstler, Jessica; Cadar, Daniel; Schmidt-Chanasit, Jonas; Jöst, Hanna

    2015-11-01

    The studie describes the blood-feeding behaviour of mosquitoes in Mexico, to understand host-vector relationships and dynamics of disease transmission. From September 2012 to November 2012 and in November 2013, 911 blood-fed Cx. quinquefasciatus mosquitoes were collected with aspirators inside houses in Chetumal and Cancun. Blood meals were analysed by PCR and subsequent Sanger sequencing of the cytochrome b gene. 93.3% of mosquitoes fed on mammals, 6.5% on birds and 0.2% on reptiles. The most frequent vertebrate hosts were humans (65.4%), dogs (23.2%), chicken (5.4%), cattle (2.2%) and cats (1.8%). Cx. quinquefasciatus most frequently fed on humans and dogs in both studied cities, which is in contrast to a previous study that demonstrated lower prevalence of mammalian blood in engorged Cx. quinquefasciatus. © 2015 John Wiley & Sons Ltd.

  1. Larvicidal efficiency of the mushroom Amanitamuscaria (Agaricales, Amanitaceae against the mosquito Culexquinquefasciatus (Diptera, Culicidae

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    Marcial Corrêa Cárcamo

    2016-02-01

    Full Text Available Abstract: INTRODUCTION: We report the larvicidal activity of two formulations from Amanita muscariaagainst Culex quinquefasciatus, as well as the viability of the aqueous extract after storage. METHODS The larvicidal activity of aqueous extract and powder from A. muscaria, and the viability of the aqueous extract after storage, were evaluated. RESULTS The aqueous extract caused larval deaths, which varied from 16.4% to 88.4%. The efficiency of the powder varied from 29.2% to 82.8%. Storage did not interfere with the larvicidal efficiency of the aqueous extract of A. muscaria. CONCLUSIONS These results show the potential of A. muscariato control C. quinquefasciatus.

  2. Pengaruh ukuran tubuh ikan Poecilia reticulata pada daya pemangsaannya terhadap larva Culex quinquefasciatus

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    Noer Moehammadi

    1999-06-01

    Full Text Available The research aimed to know the influence of poecilia reticulata body size, in the feeding capacity on Culex quinquifasciatus larvae. The research was experimental method with Complete Random Design., each treatment with 5 replications. The taken body size of Poecilia reticulata were; 1,50 cm; 2.50 cm; and 3.50 cm. the size of fish €™s body was measured from the tip of snout up to the end of fin (cm. The feeding capacity was determined by subtracting the first amount of larvae which was given the rest of larvae after 24 hours. The result showed that the difference of size of Poecilia reticulate body was significantly different in the feeding capacity on Culex quinquifasciatus larvae. The fish whose body size was 1.50 cm had the lowest feeding capacity by eating 77.2 larvae for average, and the highest one was the fist which body size was 2.50 cm by eating 113.6 larvae for average, subsequently the feeding capacity decrease to the fish which body size was 3.50 cm because of eating 100,6 larvae for 24 hours.

  3. A list of mosquito species of the Brazilian State of Pernambuco, including the first report of Haemagogus janthinomys (Diptera: Culicidae, yellow fever vector and 14 other species (Diptera: Culicidae Lista de espécies de mosquitos do Estado de Pernambuco e primeiro relato de Haemagogus janthinomys (Diptera: Culicidae vetor de febre amarela silvestre e outras 14 espécies (Diptera: Culicidae

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    Nádia Consuelo Aragão

    2010-08-01

    Full Text Available INTRODUCTION: Besides mosquito species adapted to urban environments (Culex quinquefasciatus, Aedes aegypti and Aedes albopictus, only 15 species of Anopheles had been recorded in the State of Pernambuco. METHODS: Human-landing mosquitoes were collected in Dois Irmãos Park, in Recife. RESULTS: The first report for the state of Haemagogus janthinomys, an important vector of yellow fever virus, and 14 other species, including Trichoprosopon lampropus, a first reported for Brazil. CONCLUSIONS: The mosquito fauna in the area is diversified and has potential medical and veterinary importance.INTRODUÇÃO: Além de mosquitos adaptados ao ambiente urbano (Culex quinquefasciatus, Aedes aegypti e Ae. albopictus, apenas 15 espécies de Anopheles haviam sido relatadas no Estado de Pernambuco. MÉTODOS: Mosquitos que pousavam em humanos no Parque Dois Irmãos, em Recife foram coletados. RESULTADOS: Haemagogus janthinomys, importante vetor de vírus de febre amarela, e outras 14 espécies são relatadas pela primeira vez no estado, incluindo Trichoprosopon lampropus, relatado pela primeira vez no Brasil. CONCLUSÕES: A fauna de mosquitos na área é muito diversificada e tem potencial importância médica e veterinária.

  4. Toxicity of (Burseraceae Leaf Fractions against Immature Stages of (Giles and (Say (Diptera: Culicidae

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    Lame Younoussa

    2016-01-01

    Full Text Available Mosquitoes are vectors of several human pathogens, and great attention has recently been placed on insecticides from plant-derived products, in search for mosquito control agents. This study, thus, investigated the potency of Boswellia dalzielii methanol leaf extract and its four fractions as mosquito ovicide, larvicide, and pupicide against Anopheles gambiae and Culex quinquefasciatus . The plant products were tested at the following concentrations: 125, 250, 500, 1000, and 2000 ppm on eggs and 312.5, 625, 1250, and 2500 ppm on the larvae and pupae of the mosquitoes. For results, hatchability of A. gambiae eggs was reduced to 5% with n -hexane fraction at 2000 ppm. Among the plant products tested, n -hexane fraction was most toxic against A. gambiae (LC 50 = 385.9 ppm and C. quinquefasciatus (LC 50 = 3394.9 ppm. The n -hexane fraction of B. dalzielii might be used as a mosquitocidal agent in the breeding sites of A. gambiae and C. quinquefasciatus .

  5. Assessment of long-range correlation in animal behavior time series: The temporal pattern of locomotor activity of Japanese quail (Coturnix coturnix) and mosquito larva (Culex quinquefasciatus)

    Science.gov (United States)

    Kembro, Jackelyn M.; Flesia, Ana Georgina; Gleiser, Raquel M.; Perillo, María A.; Marin, Raul H.

    2013-12-01

    Detrended Fluctuation Analysis (DFA) is a method that has been frequently used to determine the presence of long-range correlations in human and animal behaviors. However, according to previous authors using statistical model systems, in order to correctly use DFA different aspects should be taken into account such as: (1) the establishment by hypothesis testing of the absence of short term correlation, (2) an accurate estimation of a straight line in the log-log plot of the fluctuation function, (3) the elimination of artificial crossovers in the fluctuation function, and (4) the length of the time series. Taking into consideration these factors, herein we evaluated the presence of long-range correlation in the temporal pattern of locomotor activity of Japanese quail (Coturnix coturnix) and mosquito larva (Culex quinquefasciatus). In our study, modeling the data with the general autoregressive integrated moving average (ARFIMA) model, we rejected the hypothesis of short-range correlations (d=0) in all cases. We also observed that DFA was able to distinguish between the artificial crossover observed in the temporal pattern of locomotion of Japanese quail and the crossovers in the correlation behavior observed in mosquito larvae locomotion. Although the test duration can slightly influence the parameter estimation, no qualitative differences were observed between different test durations.

  6. Ecology of mosquitoes (Diptera: Culicidae in areas of Serra do Mar State Park, State of São Paulo, Brazil. II - Habitat distribution

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    Anthony Érico Guimarães

    2000-01-01

    Full Text Available The mosquito (Diptera: Culicidae ecology was studied in areas of Serra do Mar State Park, State of São Paulo, Brazil. Systematized biweekly human bait collections were made three times a day, for periods of 2 or 3 h each, in sylvatic and rural areas for 24 consecutive months (January 1991 to December 1992. A total of 24,943 adult mosquitoes belonging to 57 species were collected during 622 collective periods. Aedes scapularis, Coquillettidia chrysonotum, Cq. venezuelensis, Wyeomyia dyari, Wy. longirostris, Wy. theobaldi and Wy. palmata were more frequently collected at swampy and at flooded areas. Anopheles mediopunctatus, Culex nigripalpus, Ae. serratus, Ae. fulvus, Psorophora ferox, Ps. albipes and the Sabethini in general, were captured almost exclusively in forested areas. An. cruzii, An. oswaldoi and An. fluminensis were captured more frequently in a residence area. However, Cx. quinquefasciatus was the only one truly eusynanthropic. An. cruzii and Ae. scapularis were captured feeding on blood inside and around the residence, indicating that both species, malaria and arbovirus vectors respectively, may be involved in the transmission of these such diseases in rural areas.

  7. NCBI nr-aa BLAST: CBRC-MDOM-03-0048 [SEVENS

    Lifescience Database Archive (English)

    Full Text Available CBRC-MDOM-03-0048 ref|XP_001862567.1| medulloblastoma antigen MU-MB-50.4 [Culex qui...nquefasciatus] gb|EDS37205.1| medulloblastoma antigen MU-MB-50.4 [Culex quinquefasciatus] XP_001862567.1 4.1 31% ...

  8. Aspectos ecológicos de Anopheles cruzii e Culex ribeirensis (Diptera, Culicidae da Mata Atlântica de Morretes, Paraná, Brasil Ecological aspects of Anopheles cruzii and Culex ribeirensis (Diptera, Culicidae in Atlantic Forest of Morretes, Paraná, Brazil

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    Luiz Gonzaga dos Santos-Neto

    2008-01-01

    Full Text Available Um estudo foi realizado sobre mosquitos adultos de abril 1995 a março 1996 na Mata Atlântica do município de Morretes, Paraná, Brasil. A investigação foi procedida com auxílio de duas armadilhas luminosas CDC-M instaladas em estratos verticais diferentes. Os mosquitos foram capturados mensalmente durante um ano, com início às 18 horas e término às 6 horas do dia seguinte, totalizando 144 horas de trabalho de campo. Obteve-se 1.408 exemplares de mosquitos (409 na copa e 999 próximo ao solo, pertencentes a 10 gêneros e 31 espécies. Anopheles cruzii e Culex ribeirensis foram predominantes e são objetos do presente estudo. Não foi observada diferença entre as armadilhas para Anopheles cruzii. Mas Culex ribeirensis foi coletado em maior número pela CDC-M/solo. Anopheles cruzii, quanto à freqüência horária, apresentou picos nas primeiras horas da noite, depois a sua atividade decresceu progressivamente até o crepúsculo matutino, sem apresentar um pico secundário. Em referência a distribuição mensal, Anopheles cruzii foi mais freqüente nos meses de abril e maio de 1995 e março de 1996. Não houve correlação do número de exemplares com a temperatura ou precipitações pluviométricas. Culex ribeirensis apresentou maior atividade de vôo de 22h às 4h, mas não houve picos significativos. Nas coletas obtidas por mês, Culex ribeirensis teve picos em dezembro e janeiro. Houve correlação do número de espécimes deste culicíneo com a temperatura e precipitações pluviométricas. Constituem os primeiros registros para o Estado do Paraná: Ochlerotatus rhyacophilus, Culex misionensis, Culex pedroi, Culex ribeirensis e Culex zeteki.A study of adult mosquitoes was performed from April 1995 to March 1996 in the Atlantic Forest near to Morretes city, Paraná, Brazil. The research was carried out by using two CDC-M light traps installed in different vertical stratification levels. Mosquitoes were collected monthly throughout

  9. Additional records of vector mosquito diversity collected from Al Khor district of North-eastern Qatar

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    Mahmoud Mohammed Kardousha

    2015-10-01

    Full Text Available Objective: To survey mosquito diversity in the north-eastern area, which includes the most important gas industrial city in Qatar, and to investigate the potential mosquitoes for transmitting diseases. Methods: A study was performed from September 2009 until June 2011 in Al-Khor district of North-eastern Qatar. Five localities were selected for larval collection: Al Khor City (the main city, Al Dhakira, Ras Laffan (gas industrial city, Simsimah and Al Ghuwariyah. The survey was carried out by using different sampling methods and covering all expected natural breeding sites. The larvae were collected, preserved and transferred to the laboratory for identification. Results: Our findings revealed that 10 species of mosquito larvae had been detected from the area and five of them were new records in Qatar. The species encountered were: Ochlerotatus caspius (Pallas 1771, Anopheles stephensi (Liston 1901, Culex quinquefasciatus (Say 1823 (Cx. quinquefasciatus, Culex pipiens biotype molestus (Forskal 1775 (Cx. pipiens, Culex univittatus (Theobald 1901, Culex pusillus (Macquart 1850, Culex tritaeniorhynchus (Giles 1901 (Cx. tritaeniorhynchus, Culex laticinctus (Edwards 1913, Culex sitiens (Weidmann 1828 and Culex perexiguus (Theobald 1901. The new recorded species were Cx. quinquefasciatus, Cx. tritaeniorhynchus, Culex laticinctus, Culex sitiens and Culex perexiguus. The most prevalent type was Cx. pipiens molestus (31.29% and followed by Culex pusillus and Cx. quinquefasciatus which have relatively similar prevalence of 18.72% and 18.52% respectively. Anopheles stephensi was an established vector for malaria. Cx. pipiens molestus and Cx. quinquefasciatus were vectors of West Nile virus and filariasis. Cx. tritaeniorhynchus was established as a vector of Rift Valley virus and Culex univittatus was the main vector of Sindbis virus. Conclusions: The north-eastern area of Qatar harbors is the most important industrial city in the country, which has

  10. EST Table: AU003879 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available AU003879 ws00697 11/12/09 n.h 10/09/28 39 %/206 aa ref|XP_001867321.1| partner of drosha... [Culex quinquefasciatus] gb|EDS44779.1| partner of drosha [Culex quinquefasciatus] 10/08/28 44 %/152 a

  11. EST Table: FS920740 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS920740 E_FL_fufe_51G05_F_0 10/09/28 40 %/209 aa ref|XP_001867321.1| partner of drosha... [Culex quinquefasciatus] gb|EDS44779.1| partner of drosha [Culex quinquefasciatus] 10/09/13 39 %/204 aa

  12. Genome analysis of cytochrome P450s and their expression profiles in insecticide resistant mosquitoes, Culex quinquefasciatus.

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    Ting Yang

    Full Text Available Here we report a study of the 204 P450 genes in the whole genome sequence of larvae and adult Culex quinquefasciatus mosquitoes. The expression profiles of the P450 genes were compared for susceptible (S-Lab and resistant mosquito populations, two different field populations of mosquitoes (HAmCq and MAmCq, and field parental mosquitoes (HAmCq(G0 and MAmCq(G0 and their permethrin selected offspring (HAmCq(G8 and MAmCq(G6. While the majority of the P450 genes were expressed at a similar level between the field parental strains and their permethrin selected offspring, an up- or down-regulation feature in the P450 gene expression was observed following permethrin selection. Compared to their parental strains and the susceptible S-Lab strain, HAmCq(G8 and MAmCq(G6 were found to up-regulate 11 and 6% of total P450 genes in larvae and 7 and 4% in adults, respectively, while 5 and 11% were down-regulated in larvae and 4 and 2% in adults. Although the majority of these up- and down-regulated P450 genes appeared to be developmentally controlled, a few were either up- or down-regulated in both the larvae and adult stages. Interestingly, a different gene set was found to be up- or down-regulated in the HAmCq(G8 and MAmCq(G6 mosquito populations in response to insecticide selection. Several genes were identified as being up- or down-regulated in either the larvae or adults for both HAmCq(G8 and MAmCq(G6; of these, CYP6AA7 and CYP4C52v1 were up-regulated and CYP6BY3 was down-regulated across the life stages and populations of mosquitoes, suggesting a link with the permethrin selection in these mosquitoes. Taken together, the findings from this study indicate that not only are multiple P450 genes involved in insecticide resistance but up- or down-regulation of P450 genes may also be co-responsible for detoxification of insecticides, insecticide selection, and the homeostatic response of mosquitoes to changes in cellular environment.

  13. Potential for North American mosquitoes (Diptera: Culicidae) to transmit rift valley fever virus.

    Science.gov (United States)

    Turell, Michael J; Wilson, William C; Bennett, Kristine E

    2010-09-01

    To determine which arthropods should be targeted for control should Rift Valley fever virus (RVFV) be detected in North America, we evaluated Culex erraticus (Dyar and Knab), Culex erythrothorax Dyar, Culex nigripalpus Theobald, Culex pipiens L., Culex quinquefasciatus Say, Culex tarsalis Coquillett, Aedes dorsalis (Wiedemann), Aedes vexans (Meigen), Anopheles quadrimaculatus Say, and Culicoides sonorensis Wirth and Jones from the western, midwestern, and southern United States for their ability to transmit RVFV. Female mosquitoes were allowed to feed on adult hamsters inoculated with RVFV, after which engorged mosquitoes were incubated for 7-21 d at 260C, then allowed to refeed on susceptible hamsters, and tested to determine infection, dissemination, and transmission rates. Other specimens were inoculated intrathoracically, held for 7 d, and then allowed to feed on a susceptible hamster to check for a salivary gland barrier. When exposed to hamsters with viremias > or =10(8.8) plaque-forming units/ml blood, Cx. tarsalis transmitted RVFV efficiently (infection rate = 93%, dissemination rate = 56%, and estimated transmission rate = 52%). In contrast, when exposed to the same virus dose, none of the other species tested transmitted RVFV efficiently. Estimated transmission rates for Cx. erythrothorax, Cx. pipiens, Cx. erraticus, and Ae. dorsalis were 10, 8, 4, and 2%, respectively, and for the remaining species were feeding preference, longevity, and foraging behavior should be considered when determining the potential role that these species could play in RVFV transmission.

  14. Distribuição sazonal de Culex (Culex eduardoi Casal & Garcia (Diptera, Culicidae em criadouros antrópicos introduzidos em mata residual degradada, área urbana de Curitiba, Paraná,Brasil Seazonal distribution of Culex (Culex eduardoi Casal & Garcia (Diptera, Culicidae in artificial receptacles in disturbed patch of forest degraded inurban area of Curitiba, Paraná, Brazil

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    Magda Clara Vieira da Costa Ribeiro

    2002-07-01

    Full Text Available The utilization of artificial receptacles to oviposition by mosquitoes in forest environment may indicate a sinantropic tendency or behaviour. Our data revealed that tires were as the most acceptable breeding for Culex (Culex eduardoi Casal & Garcia 1968.The population density of this species was higher and summer seasons.

  15. Influence of Bloodmeal Source on Reproductive Output of the Potential West Nile Vector, Culex theileri (Diptera: Culicidae).

    Science.gov (United States)

    Demirci, Berna; Durmaz, Esra; Alten, Bulent

    2014-11-01

    Culex theileri Theobald (Diptera: Culicidae) has a wide Afrotropical, southern Palaearctic, northern Oriental, and European distribution. It is mainly considered as a mammophilic mosquito and also feeds on birds and serves as a vector for various zoonotic diseases including West Nile virus. Despite its broad distribution and evidence indicating that Cx. theileri is a competent vector of human and domestic animal pathogens, basic biological and ecological features of this species have not been well investigated. We evaluated the impact of bloodmeal source (human, chicken, cow, and a double bloodmeal such as human and cow or chicken and cow and mixed bloodmeals [cow, chicken, and human] via artificial feeding) on fecundity, hatching rates, developmental times, and viability from egg to adult for laboratory colonized Cx. theileri. Fecundity in mosquitoes that took a chicken bloodmeal, a double bloodmeal and mixed bloodmeals was significantly higher than in females fed on a single cow or single human blood. This is the first study about the bloodmeal sources effect on laboratory-reared Cx. theileri populations and these findings contribute to our understanding of the impact of bloodmeal source on reproduction in Cx. theileri. As it is known that Cx. theileri is a vector for West Nile virus, the potential impacts of bloodmeal source on virus transmission are discussed. © 2014 Entomological Society of America.

  16. Biosynthesis, mosquitocidal and antibacterial properties of Toddalia asiatica-synthesized silver nanoparticles: do they impact predation of guppy Poecilia reticulata against the filariasis mosquito Culex quinquefasciatus?

    Science.gov (United States)

    Murugan, Kadarkarai; Venus, Joseph Selvaraj Eugine; Panneerselvam, Chellasamy; Bedini, Stefano; Conti, Barbara; Nicoletti, Marcello; Sarkar, Santosh Kumar; Hwang, Jiang-Shiou; Subramaniam, Jayapal; Madhiyazhagan, Pari; Kumar, Palanisamy Mahesh; Dinesh, Devakumar; Suresh, Udaiyan; Benelli, Giovanni

    2015-11-01

    Mosquito-borne diseases represent a deadly threat for millions of people worldwide. Furthermore, pathogens and parasites polluting water also constitute a severe plague for populations of developing countries. In this study, silver nanoparticles (AgN) were biosynthesized a cheap aqueous extract of T. asiatica leaves as reducing and stabilizing agent. The formation of nanoparticle was confirmed by surface Plasmon resonance band illustrated in UV-vis spectrophotometer. AgN were characterized by FTIR, SEM, EDX, and XRD analyses. AgN were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and their mean size was 25-30 nm. T. asiatica aqueous extract and green-synthesized AgN showed excellent larvicidal and pupicidal toxicity against the filariasis vector Culex quinqufasciatus, both in laboratory and field experiments. AgN LC50 ranged from 16.48 (I instar larvae) to 31.83 ppm (pupae). T. asiatica-synthesized were also highly effective in inhibiting growth of Bacillus subtilis, Klebsiella pneumoniae, and Salmonella typhi using the agar disk diffusion and minimum inhibitory concentration protocol. Lastly, we evaluated if sublethal doses of nanoparticles affect predation rates of fishes, Poecilia reticulata, against C. quinquefasciatus. In AgN-contaminated environment, predation of guppies against mosquito larvae was slightly higher over normal laboratory conditions. Overall, this study highlighted that T. asiatica-synthesized AgN are easy to produce, stable over time, and may be employed at low dosages to reduce populations of filariasis vectors, without detrimental effects on predation rates of mosquito natural enemies.

  17. MODELO BIOGEOGRÁFICO DE LOS MOSQUITOS CULEX SPP. (DIPTERA: CULICIDAE EN MÉXICO

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    Maria Torres Olave

    2015-12-01

    Full Text Available The mosquitoes distribution and the presence of arboviruses are determined by temperature, rainfall, geographic barriers, and other factors that determine the distribution of Culex spp. and can influence the human arboviral. The objective of this study was to identify potential spatial distribution of Culex spp. The ecological niche modeling was performed using MaxEnt Ecological niche modeling was performed using MaxEnt, bioclimatic variables (WorldClim used for this process are derived from the monthly values of temperature and precipitation to generate biologically significant variables (representing annual trends and limiting factors for the distribution of species. The resulting maps can be interpreted as relative suitability areas, these areas are presented on the east coast of Mexico, mainly in the states of Veracruz and Tabasco. The results show that Bio 2 (mean monthly temperature range, Bio 7 (annual range of temperature and Bio 11 (mean temperature of the coldest quarter, determine the highest percentage range. Distribution modeling Culex spp. It is an approach to identify the most vulnerable areas in Mexico. It is necessary to strengthen and establish multidisciplinary programs for the prevention ofCulexspp transmitted diseases.

  18. Larvicidal Activity of Nerium oleander against Larvae West Nile Vector Mosquito Culex pipiens (Diptera: Culicidae

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    Fouad El-Akhal

    2015-01-01

    Full Text Available Background. Outbreaks of the West Nile virus infection were reported in Morocco in 1996, 2003, and 2010. Culex pipiens was strongly suspected as the vector responsible for transmission. In the North center of Morocco, this species has developed resistance to synthetic insecticides. There is an urgent need to find alternatives to the insecticides as natural biocides. Objective. In this work, the insecticidal activity of the extract of the local plant Nerium oleander, which has never been tested before in the North center of Morocco, was studied on larval stages 3 and 4 of Culex pipiens. Methods. Biological tests were realized according to a methodology inspired from standard World Health Organization protocol. The mortality values were determined after 24 h of exposure and LC50 and LC90 values were calculated. Results. The extract had toxic effects on the larvae of culicid mosquitoes. The ethanolic extract of Nerium oleander applied against the larvae of Culex pipiens has given the lethal concentrations LC50 and LC90 in the order of 57.57 mg/mL and 166.35 mg/mL, respectively. Conclusion. This investigation indicates that N. oleander could serve as a potential larvicidal, effective natural biocide against mosquito larvae, particularly Culex pipiens.

  19. Susceptibility Of Mosquito Larvae To Conventional Insecticides In A ...

    African Journals Online (AJOL)

    ... 0.48, 37.09 and 0.29 μg per liter respectvely. The LD50 values for Culex quinquefasciatus of exposed to dieldrin, dichlovos and cypermethrin were 0.11 10.05 and 005 μg per liter respectively. Keywords: Aedes aegypti, Culex quinquefasciatus, LC50, Dieldrin, Dichlovos, Cypermethrin. Animal Research International Vol.

  20. Evaluation of temephos and chlorpyrifos-methyl against Culex pipiens (Diptera: Culicidae) larvae in septic tanks in Antalya, Turkey.

    Science.gov (United States)

    Cetin, H; Yanikoglu, A; Kocak, O; Cilek, J E

    2006-11-01

    The larvicidal activity of chlorpyrifos-methyl and temephos was evaluated against Culex pipiens L. (Diptera: Culicidae) in septic tanks in Antalya, Turkey. Chlorpyrifos-methyl (Pyrifos MT 25 emulsifiable concentrate [EC] ) was evaluated at application rates of 0.04, 0.08, and 0.12 mg active ingredient (AI)/liter, and temephos (Temeguard 50 EC) was evaluated at 0.02, 0.04, and 0.06 mg (AI)/liter during a 21-d study. Generally, overall larval reduction in septic tanks from single- and multifamily dwellings treated with either larvicide was significantly greater than pretreatment levels and control tanks for the duration of the study. At 14 d posttreatment, duration of control was greatest in multifamily tanks treated with chlorpyrifos-methyl at the highest application rate with similar levels of control through 21 d for single-family dwellings (range 97-100%). Septic tanks from both types of family dwellings treated at the highest application rate of temephos resulted in >90% reduction through day 21 (range 91-100%). Laboratory bioassays of septic tank water treated at field application rates, without daily dilution, revealed that complete larval mortality was achieved for 21 d at each application rate and formulation. It is thought that daily addition of water and organic matter to the septic tanks in the single and multifamily dwellings influenced the duration of effectiveness of the larvicides.

  1. Identification of entomopathogenic Bacillus isolated from Simulium (Diptera, Simuliidae larvae and adults

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    Cavados CFG

    2001-01-01

    Full Text Available Entomopathogenic bacteria isolated from Simulium larvae and adults from breeding sites in the states of São Paulo and Rio de Janeiro, Brazil, were identified as 18 strains of Bacillus thuringiensis and one of B. sphaericus. Most of these strains were serotyped according to their flagellar antigens. However, nine of the B. thuringiensis samples, could not be serotyped and were designated as "autoagglutinating"; they were also shown to be toxic in preliminary tests against Aedes aegypti larvae. Additionally, B. sphaericus was also shown to be toxic towards Culex quinquefasciatus larvae.

  2. EST Table: FS916089 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS916089 E_FL_fufe_37E08_F_0 10/09/28 43 %/186 aa ref|XP_001843810.1| mediator comp...lex [Culex quinquefasciatus] gb|EDS34592.1| mediator complex [Culex quinquefasciatus] 10/09/12 36 %/187 aa F...1082463|ref|XP_971521.1| PREDICTED: similar to mediator complex [Tribolium castaneum] BJ984999 fufe ...

  3. Host-Feeding Patterns of Culex stigmatosoma (Diptera: Culicidae) in Southern California.

    Science.gov (United States)

    McPhatter, Lee P; Su, Tianyun; Williams, Greg; Cheng, Min-Lee; Dhillon, Major; Gerry, Alec C

    2017-11-07

    Knowledge of the blood-feeding patterns exhibited by arthropod vectors is essential for understanding the complex dynamics of vector-borne disease transmission. Some species of mosquitoes belonging to the genus Culex have been implicated as having major roles in the transmission of arboviruses such as West Nile virus, Saint Louis encephalitis virus, and Western equine encephalitis virus. Although the host-feeding patterns for many of these Culex species are well studied, the host-feeding patterns of Culex stigmatosoma Dyar are relatively poorly studied, even though this species is suspected to be an important maintenance vector for West Nile virus and other arboviruses. In the current study, bloodmeals from 976 blood-engorged Cx. stigmatosoma, collected from 30 sites in southern California from 2009-2012, were processed for vertebrate host identification by nucleotide sequencing following polymerase chain reaction to amplify portions of the cytochrome oxidase I and cytochrome b genes of vertebrate animals. Vertebrate DNA was amplified, sequenced, and identified from a total of 647 Cx. stigmatosoma bloodmeals, revealing that 98.6% of bloodmeals were from birds, 1.2% from three mammal species, and a single bloodmeal was from a reptile species. In total, 40 different host species were identified. The greatest number of bloodmeals identified was from domestic chicken (Gallus gallus domesticus L.) (38% of bloodmeals), house sparrow (Passer domesticus L.) (23%), house finch (Haemorhous mexicanus Müller) (17%), American crow (Corvus brachyrhynchos L.) (4%), and mourning dove (Zenaida macroura L.) (3%). However, chicken bloodmeals were identified almost entirely from a single site where mosquito collection devices were placed in the near vicinity of confined domestic chickens. The strongly ornithophilic feeding behavior shown in this study for Cx. stigmatosoma supports the hypothesis that this mosquito species may be an important maintenance (or endemic) vector for

  4. Taxonomic study and redescription of Culex (Melanoconion theobaldi (Lutz, 1904 (Diptera: Culicidae

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    Oswaldo Paulo Forattini

    1989-01-01

    Full Text Available Based on type examination, Culex (Melanoconion theobaldi (Lutz, 1904 is redescribed. The species Cx. (Mel. chrysonotum Dyar & Knab, 1908, was put back as synonym of theobaldi. Besides, examination of Cx. (Mel. chrysothorax (Newstead & Thomas, 1910 type, leads to retiring as synonym of theobaldi and considered it as "species inquirenda".

  5. Evaluation of the naturally-derived insecticide spinosad against Culex pipiens L. (Diptera: Culicidae) larvae in septic tank water in Antalya, Turkey.

    Science.gov (United States)

    Cetin, Huseyin; Yanikoglu, Atila; Cilek, James E

    2005-06-01

    The naturally-derived insecticide spinosad (Conserve SC) was evaluated against larval Culex pipiens L. (Diptera: Culicidae) under laboratory and field conditions in Antalya, Turkey. Laboratory bioassays showed that the 24 h LC50 and LC90 against late 3rd and early 4th instars were estimated at 0.027 and 0.111 parts per million, respectively, while adult emergence was eliminated at concentrations above 0.06 ppm. Larval mortality from septic tanks that were treated with spinosad at rates of 25, 50, 100, and 200 g ai/ha ranged between 22 to 78% 1 day after application. At 7 days post-treatment, larval mortality ranged from 2 to 50% and at 14 days mortality was septic tanks treated at 100 and 200 g ai/ha resulted in an elimination of Cx. pipiens larvae 7 days after treatment. After this time, larval reduction declined to 79 and 83%, respectively, 14 days after treatment. Larval reduction in septic tanks treated at the two lowest rates (i.e. 25 and 50 g ai/ha) ranged from 14 to 74% during the 14-day study. These results indicated that spinosad can be considered an effective larvicide for treatment of septic tanks against Cx. pipiens.

  6. Genetic Variations in Bionomics of (Diptera: Culicidae Mosquito Population in Minna, North Central Nigeria

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    Azubuike C. Ukubuiwe

    2016-01-01

    Full Text Available The need to have an improved knowledge on the bioecology of Culex quinquefasciatus , a prerequisite in the development of cost-effective control strategies, has informed the present preliminary investigation to put in better perspective variations that exist in the egg rafts of the species. Freshly laid egg rafts were collected and incubated at ambient temperature in well-labeled plastic trays. The results showed overall inconsistency in all indices monitored for the egg rafts. Generally, survivorship was high for the species. All immature stage and adult parameters measured varied significantly among the egg rafts and between/within sexes of the species. Therefore, this study suggests the presence of inherent variation in the bionomics of egg rafts of C. quinquefasciatus , probably influenced by the environment and hence underscores the need for additional studies to further elucidate the roles of genetics and environment in vectorial competence of the species, in order to develop robust sustainable mosquito vector control protocols.

  7. A first note on Japanese encephalitis virus isolation from Culex quinquefasciatus Say in Northern West Bengal.

    OpenAIRE

    V. Thenmozhi; T. Mariappan; R. Krishnamoorthy; R. Krishnamoorthi; T. Balaji; B. K. Tyagi; V. Thenmozhi

    2014-01-01

    Japanese encephalitis (JE) is endemic in many parts of India including the state of West Bengal. In West Bengal, the first major outbreaks of JE occurred in the districts of Bankura and Burdwan in 1973. The Culex vishnui subgroup of mosquitoes has been implicated as major vectors of JE. However in India, JE virus (JEV) has been isolated from 16 species of mosquitoes. During September 2011, JE cases were reported from four districts -Jalpaiguri, Darjeeling, Dinajpur and Cooch Behar of West Ben...

  8. Exploring Mosquito Fauna of Majuro Atoll (Republic of Marshall Islands) in the Context of Zika Outbreak.

    Science.gov (United States)

    Marie, Jérôme; Perera, Devika; Garstang, Helentina; Bossin, Herve C; Bourtzis, Kostas

    2018-04-09

    First autochthonous Zika clinical case was reported in the Republic of Marshall Islands (RMI) on Majuro Atoll in February 2016. An entomological survey of mosquito larvae and adult populations was carried out in four areas of Majuro, the most populated atoll of RMI encompassing different habitats (forest, rural, or urban) including some with confirmed clinical Zika cases to evaluate which mosquito species could be involved in the Zika transmission. A total of 2,367 immature and adult mosquito specimens were collected and identified to the species level. In total, five mosquito species were detected, Aedes aegypti (Linnaeus), Aedes albopictus (Skuse), Aedes marshallensis (Stone and Bohart), Culex quinquefasciatus (Say), and Culex annulirostris (Skuse) (Diptera: Culicidae), a first record for RMI. The most abundant species was Ae. aegypti presumed to be the main vector of Zika virus followed by Ae. albopictus. Improved management of breeding containers through better public awareness and community engagement, mosquito surveillance and innovative mosquito control strategies using the sterile insect technique (SIT) and/or the incompatible insect technique (IIT) could help prevent outbreaks of arboviruses in the RMI.

  9. Field evaluation of spatial repellency of metofluthrin impregnated plastic strips against mosquitoes in Hai Phong city, Vietnam.

    OpenAIRE

    Kawada, Hitoshi; Nguyen Thi Yen; Nguen Thuy Hoa; Truong Minh Sang; Nguyen Van Dan; Takagi, Masahiro

    2005-01-01

    Spatial repellency of metofluthrin-impregnated polyethylene plastic strips against mosquitoes, Aedes aegypti and Culex quinquefasciatus, were studied in a residential area in Hai Phong city, Vietnam. Thirty houses were selected as trial sites; half of these were assigned as untreated control and the other half were assigned for treatment.Primarily, irrespective of the room size, one room was treated with one strip. The dominant species in the trial sites were Culex quinquefasciatus and Aedes ...

  10. Comparative analysis of gut microbiota of Culex restuans (Diptera: Culicidae) females from different parents

    Science.gov (United States)

    The potential for gut microbiota to impede or enhance pathogen transmission is well-documented but the factors that shape this microbiota in mosquito vectors are poorly understood. We characterized and compared the gut microbiota of adult females of Culex restuans Theobald from different parents. Cu...

  11. Culicidae (Diptera, Culicomorpha from the western Brazilian Amazon: Juami-Japurá Ecological Station

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    Rosa Sá Gomes Hutchings

    2010-01-01

    Full Text Available With 312 trap-hours of sampling effort, 1554 specimens of Culicidae (Diptera were collected, using CDC and Malaise traps, in nine different locations along the Juami River, within the Juami-Japurá Ecological Station, Amazonas State, Brazil. A list of mosquito species with 54 taxa is presented, which includes three new distributional records for the state of Amazonas. The species found belong to the genera Anopheles, Aedeomyia, Aedes, Psorophora, Culex, Coquillettidia, Sabethes, Wyeomyia and Uranotaenia.

  12. Hepatozoon cf. terzii (Sambon & Seligman, 1907 infection in the snake Boa constrictor constrictor from north Brazil: transmission to the mosquito Culex quinquefasciatus and the lizard Tropidurus torquatus

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    Paperna I.

    2004-06-01

    Full Text Available Specimens of Hepatozoon-infected Boa constrictor constrictor were obtained from localities in Pará State, north Brazil. Gametocytes in erythrocytes of the peripheral blood measured 10 x 2.5-16.2 x 3.7 µm. They were similar to those described as Haemogregarina terzii by Sambon & Seligmann (1907 in B. c. constrictor, in that they did not distort the infected erythrocyte, and their dimensions approximated those given by Carini (1947. Lungs and liver of infected snakes contained actively dividing meronts of a single type, and cysts containing two to six cystozoites were also present in the liver. Our initial feeding of Culex quinquefasciatus on infected snakes consistently resulted in a heavy death-rate of the engorged mosquitoes, with only a few surviving till the 9th day post feeding. These contained numerous oocysts which were undivided or in early stages of division. A fifth and final experiment, however, provided a few mosquitoes surviving up to 21 days post infection (dpi, and these contained fully sporulated oocysts measuring 190-200 µm in diameter and containing over 60 sporocysts of 19-30 µm in diameter. The number of sporozoites in each sporocyst was estimated as approximately 50. The nature of the parasite's sporogonic cycle in the mosquito thus justifies inclusion of this haemogregarine in the genus Hepatozoon. Two wild-caught specimens of the lizard Tropidurus torquatus were fed with mosquitoes containing fully developed oocysts (21 dpi. When sacrificed, three months later, large numbers of dizoic, tetrazoic and hexazoic cysts were demonstrated in their livers. Cystozoites released from these cysts were shown to possess a conspicuous refractile body.

  13. Natural infection of Culex theileri (Diptera: Culicidae) with Dirofilaria immitis (Nematoda: Filarioidea) on Madeira Island, Portugal.

    Science.gov (United States)

    Santa-Ana, Marta; Khadem, Manhaz; Capela, Ruben

    2006-01-01

    Field and laboratory studies were performed to verify whether Culex theileri Theobald functions as a natural vector of Dirofilaria immitis (Leidy) on Madeira Island, Portugal. CO2-baited light traps (EVS traps) were use to sample mosquitoes monthly basis between February 2002 and February 2003 in the area of Quebradas (Funchal). Three mosquito species were captured, including 58 Culex pipiens L., 790 Cx. theileri, and three Culiseta longiareolata (Macquart). Only C. theileri tested positive for D. immitis. The presence of this filarial worm was detected by direct observation, infectivity assay dissection technique, and polymerase chain reaction methods. Infected mosquitoes were recovered in October and December 2002 and January 2003. These data provide evidence that Cx. theileri could be the main vector of D. immitis in Funchal, Madeira.

  14. OVIPOSITION AND OVICIDAL ACTIVITIES OF ALKALOIDAL ...

    African Journals Online (AJOL)

    1000 ppm concentration and ovicidal activity at 25-100 ppm concentration against Culex quinquefasciatus and Culex tritaeniorhynchus. Water treated with alkaloidal extract at 1000ppm received significantly more egg rafts of vector mosquitoes ...

  15. Capacity of the terrestrial entomopathogenic nematode Steinernema rarum (Rhabditida: Steinernematidae to parasite Culex apicinus larvae (Diptera: Culicidae Capacidad del nemátodo terrestre entomopatógeno Steinernema rarum (Rhabditida: Steinernematidae de parasitar larvas de Culex apicinus (Diptera: Culicidae

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    Susana R. Cagnolo

    2010-06-01

    Full Text Available Entomopathogenic nematodes can be considered effective agents for biocontrol, resulting innocuous for humans. Larvaeof Culex apicinus Philippi were exposed to infective juveniles of Steinernema rarum (OLI strain under laboratory conditions, testing six doses (1:1, 5:1, 10:1, 15:1, 100:1, 400:1. An increasing percentage of mosquito larvae mortality was recorded with an increased dose. The highest percentage of mosquito larvae mortality (75% was obtained with the dose 400:1. This is the first report of parasitism of an isolated of S. rarum from Córdoba against larvae of C. apicinus, with promising results. Therefore, further studies must be carried out to determine if these nematodes would be effective as autochthonous agents for the control of Culex Linnaeus and other mosquitoes of sanitary interest in the country.Los nemátodos entomopatógenos son considerados eficientes agentes de control de insectos plaga e inocuos para los humanos. Larvas de Culex apicinus Philippi fueron expuestas a seis dosis (1:1, 5:1, 10:1, 15:1, 100:1, 400:1 de juveniles infectivos de Steinernema rarum (aislado OLI. Se registró un incremento en la mortalidad de las larvas del mosquito con el aumento de la dosis del nematodo. El mayor porcentaje de mortalidad de larvas del mosquito (75% se obtuvo con la dosis 400:1. Este es el primer reporte de parasitismo de un aislado de S. rarum de Córdoba, en larvas de C. apicinus con resultados promisorios. Por lo tanto, se debería profundizar su estudio para determinar si pueden resultar efectivos como agentes autóctonos para el control biológico de mosquitos Culex Linnaeus, y otros de interés sanitario en el país.

  16. Repellency and toxicity of aromatic plant extracts against the mosquito Culex pipiens molestus (Diptera: Culicidae).

    Science.gov (United States)

    Traboulsi, Abdallah F; El-Haj, Samih; Tueni, Marie; Taoubi, Khalil; Nader, Natalie Abi; Mrad, Abir

    2005-06-01

    The insecticidal activities of essential oil extracts from leaves, flowers and roots of aromatic plants against fourth-instar larvae of the mosquito Culex pipiens molestus Forskal were determined. Extracts of Foeniculum vulgare Mill were the most toxic, followed by those of Ferula hermonis Boiss, Citrus sinensis Osbeck, Pinus pinea L, Laurus nobilis L and Eucalyptus spp with LC50 values of 24.5, 44.0, 60.0, 75.0, 117.0 and 120.0 mg litre(-1), respectively. Combination tests between the LC50 and the maximum sub-lethal concentration (MSLC) were determined. Over 20 major components were identified in extracts from each plant species tested. Five essential oils and nine pure components were studied for their repellency against mosquito bites. Terpineol and 1,8-cineole were the most effective against Culex pipiens molestus bites offering complete protection for 1.6 and 2 h, respectively.

  17. COMPARATIVE STUDIES ON MAN-BITING POPULATION OF FILARIAL VECTOR Cx. quinquefasciatus (Diptera: Culicidae BETWEEN TRIBAL AND NON-TRIBAL AREAS OF BANKURA DISTRICT, WEST BENGAL INDIA

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    G. Chandra

    2012-10-01

    Full Text Available West Bengal, India is endemic for filariasis and the number of patients infected with bancroftian filariasis is increasing. There are no observation on the potential vector of filariasis from the tribal areas that make up considerable part in this state. This study investigate population of Cx. quinquefasciatus in tribal and non-tribal areas of Bankura district. Species composition of mosquitoes, per man-hour density, hourly densities of night biting Cx. quinquefasciatus, number of Cx. quinquefasciatus biting per man per day and per man per night. Preferential biting site and peak period of filarial transmission were recorded from both the study areas. Infection rate, infectivity rate of man-landing vector population and annual transmission potential were observed to be 0.31%, 0.00% and 0.00 in tribal areas and 0.73%, 0.23% and 359.71 in non-tribal areas respectively.

  18. Diversity of Wolbachia pipientis strain wPip in a genetically admixtured, above-ground Culex pipiens (Diptera: Culicidae) population: association with form molestus ancestry and host selection patterns.

    Science.gov (United States)

    Morningstar, Rebecca J; Hamer, Gabriel L; Goldberg, Tony L; Huang, Shaoming; Andreadis, Theodore G; Walker, Edward D

    2012-05-01

    Analysis of molecular genetic diversity in nine marker regions of five genes within the bacteriophage WO genomic region revealed high diversity of the Wolbachia pipentis strain wPip in a population of Culex pipiens L. sampled in metropolitan Chicago, IL. From 166 blood fed females, 50 distinct genetic profiles of wPip were identified. Rarefaction analysis suggested a maximum of 110 profiles out of a possible 512 predicted by combinations of the nine markers. A rank-abundance curve showed that few strains were common and most were rare. Multiple regression showed that markers associated with gene Gp2d, encoding a partial putative capsid protein, were significantly associated with ancestry of individuals either to form molestus or form pipiens, as determined by prior microsatellite allele frequency analysis. None of the other eight markers was associated with ancestry to either form, nor to ancestry to Cx. quinquefasciatus Say. Logistic regression of host choice (mammal vs. avian) as determined by bloodmeal analysis revealed that significantly fewer individuals that had fed on mammals had the Gp9a genetic marker (58.5%) compared with avian-fed individuals (88.1%). These data suggest that certain wPip molecular genetic types are associated with genetic admixturing in the Cx. pipiens complex of metropolitan Chicago, IL, and that the association extends to phenotypic variation related to host preference.

  19. Evaluation of immature mosquitocidal properties of Xanthium strumarium Linn. plant extracts against Culex mosquitoes (Diptera: Culicidae

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    Kasim Roba

    2015-11-01

    Full Text Available Objective: To evaluate immature mosquitocidal properties of Xanthium strumarium plant extracts against Culex mosquitoes at Entomology Laboratory, Maraki Campus, University of Gondar. Methods: The immature mosquitocidal activity of plant extracts was tested by following World Health Organization recommended protocol. Acetone, methanol and water extracts were prepared at 50, 100, 150, 200 and 250 mg/L concentrations and tested against third and fourth instar larvae and pupae of Culex mosquitoes. The mortality rate of immature mosquitoes was recorded after 24, 48 and 72 h exposure period continuously. Results: Third instar larvae after 24 h exposure period, maximum mortality of 77.80% was recorded at 250 mg/L concentration of acetone extract. After 48 h and 72 h exposure period, maximum mortality of 88.90% was recorded in acetone extract in all the tested concentration. The maximum mortality of fourth instar larvae was 88.90% in acetone extract at 200 and 250 mg/L concentrations. Pupal mortality was also greater in acetone extract. The percentage of mortality in all the stage of mosquitoes was higher in acetone extract followed by methanol and water extract. Conclusions: The percentage of mortality is associated with concentration of the extracts tested and exposure period. This laboratory study confirmed immature mosquitocidal activity of Xanthium strumarium leaf extracts against Culex mosquitoes. The aqueous leaf extract can be used by applying on small man-made breeding places to prevent adult emergence.

  20. Ecologia de mosquitos (Diptera, Culicidae em criadouros naturais e artificiais de área rural do norte do Parana, Brasil: II. Coletas com isca humana Ecology of mosquitoes (Diptera, Culicidae in natural and artificial breeding sites of the rural area in north Paraná, Brazil: II. Capture of human bait

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    José Lopes

    1996-01-01

    Full Text Available With then purpose of knowing the species of mosquitos that colonize an anthropogenic area in the North of Paraná, Brazil. 1496 specimens were captured by the humam bait method, accountig 23 species among them the following were predominam: Anopheles strodei Root, 1926; An. evansae Brethes, 1926; An. galvaoi Causey, Deane & Deane, 1943; An. albitarsis Lynch Arribalzaga, 1878; Coquillettidea juxtamansonia Chagas, 1907; Co. venezuelensis Theobaldi, 1912; Culex (Melanoconion sp. e Aedes fluviatilis (Lutz, 1904 and showed shong anthopophilia and a high degree of adaptation to humam environment. On the cantray, the species that showed lilth adaptation to such ambients or to the geoclimatic conditions of the region were: Anopheles triannulatus (Neiva & Pinto, 1922; An. parvus (Chagas, 1907; An. lutzii Cruzi, 1901, Culex amazonensis (Lutz, 1905; Cx. chidesteri; Psorophora confinnis (Linch Arribalzaga, 1891; Ps. discrucians (Walker, 1856; Ps. cingulata (Fabricius, 1805 e Aedes scapularis. Although Anopheles argyritarsis Robineau-Desvoidy, 1827; Culex coronator Dyar & Knab, 1906; Cx. mollis Dyar & Knab, 1906 and Cx. quinquefasciatus Say, 1823, were captured in little numbers, it is knowntht they an mosquito of human surroundings. These mosquitos showed a plak of feeding activity directly related to sunset bat did not have a bimodal behaviour. Anophelinae were in general more active in spring while Culex Linnaeus, 1758; Coquillettidia Dyar, 1905; Aedes Meigen, 1818; Mansonia Blanchard, 1901 e Psorophora Robineau-Desvoidy, 1827 were more active in summer.

  1. Experimental hut evaluation of bednets treated with an organophosphate (chlorpyrifos-methyl or a pyrethroid (lambdacyhalothrin alone and in combination against insecticide-resistant Anopheles gambiae and Culex quinquefasciatus mosquitoes

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    Corbel Vincent

    2005-05-01

    Full Text Available Abstract Background Pyrethroid resistant mosquitoes are becoming increasingly common in parts of Africa. It is important to identify alternative insecticides which, if necessary, could be used to replace or supplement the pyrethroids for use on treated nets. Certain compounds of an earlier generation of insecticides, the organophosphates may have potential as net treatments. Methods Comparative studies of chlorpyrifos-methyl (CM, an organophosphate with low mammalian toxicity, and lambdacyhalothrin (L, a pyrethroid, were conducted in experimental huts in Côte d'Ivoire, West Africa. Anopheles gambiae and Culex quinquefasciatus mosquitoes from the area are resistant to pyrethroids and organophosphates (kdr and insensitive acetylcholinesterase Ace.1R. Several treatments and application rates on intact or holed nets were evaluated, including single treatments, mixtures, and differential wall/ceiling treatments. Results and Conclusion All of the treatments were effective in reducing blood feeding from sleepers under the nets and in killing both species of mosquito, despite the presence of the kdr and Ace.1R genes at high frequency. In most cases, the effects of the various treatments did not differ significantly. Five washes of the nets in soap solution did not reduce the impact of the insecticides on A. gambiae mortality, but did lead to an increase in blood feeding. The three combinations performed no differently from the single insecticide treatments, but the low dose mixture performed encouragingly well indicating that such combinations might be used for controlling insecticide resistant mosquitoes. Mortality of mosquitoes that carried both Ace.1R and Ace.1S genes did not differ significantly from mosquitoes that carried only Ace.1S genes on any of the treated nets, indicating that the Ace.1R allele does not confer effective resistance to chlorpyrifos-methyl under the realistic conditions of an experimental hut.

  2. Larvicidal properties of Lepidagathis alopecuroides and Azadirachta ...

    African Journals Online (AJOL)

    GRACE

    2006-05-02

    May 2, 2006 ... Comparative analysis of the larvicidal properties of aqueous extracts of leaves of Lepidagathis alopecuroides and Azadirachta indica (neem) was carried out on Anopheles gambiae and Culex quinquefasciatus. Assays showed that L. alopecuroides was more toxic to both larvae, while C. quinquefasciatus ...

  3. Feeding Behavior and Spatial Distribution of Culex Mosquitoes (Diptera: Culicidae) in Wetland Areas of the Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Rádrová, J.; Šeblová, V.; Votýpka, Jan

    2013-01-01

    Roč. 50, č. 5 (2013), s. 1097-1104 ISSN 0022-2585 Institutional support: RVO:60077344 Keywords : Culex * spatial distribution * WNV * Rabensburg virus * feeding preference Subject RIV: EG - Zoology Impact factor: 1.815, year: 2013

  4. Biological activity of Xanthium strumarium seed extracts on different cancer cell lines and Aedes caspius, Culex pipiens (Diptera: Culicidae

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    Fahd A. Al-Mekhlafi

    2017-05-01

    Full Text Available Effects of methanol extracts of Xanthium strumarium on different cancer cell lines and on the mortality rates of Aedes caspius, Culex pipiens (Diptera: Culicidae were investigated. Among the cell lines tested, the Jurkat cell line was the most sensitive to the methanol extract and ethyl acetate fraction, with reported LC50 values of 50.18 and 48.73 μg/ml respectively. Conversely, methanol extracts were not that toxic to the A549 cell line though the toxicity increased on further purification. The percentage of growth inhibition was dose dependent for the methanol extract and ethyl acetate fraction. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The results showed that methanol extracts of plant seeds caused 100% mortality of mosquito larvae at a concentration of 1000 μg/ml after 24 h of treatment. The LC50 and LC90 values of X. strumarium were found to be 531.07 and 905.95 μg/ml against Ae. caspius and 502.32 and 867.63 μg/ml against Cx. Pipiens, respectively. From the investigations, it was concluded that the crude extract of X. strumarium showed a weak potential for controlling the larval instars of Ae. caspius and Cx. pipiens. However, on further purification the extract lost the larvicidal activity. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The ethyl acetate fraction investigated in this study appears to have a weak larvicidal activity but a promising cytotoxic activity. Future studies will include purification and investigation in further detail of the action of X. strumarium on Cancer Cell Lines and mosquitoes.

  5. Biological activity of Xanthium strumarium seed extracts on different cancer cell lines and Aedes caspius, Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Al-Mekhlafi, Fahd A; Abutaha, Nael; Mashaly, Ashraf M A; Nasr, Fahd A; Ibrahim, Khalid E; Wadaan, Mohamed A

    2017-05-01

    Effects of methanol extracts of Xanthium strumarium on different cancer cell lines and on the mortality rates of Aedes caspius, Culex pipiens (Diptera: Culicidae) were investigated. Among the cell lines tested, the Jurkat cell line was the most sensitive to the methanol extract and ethyl acetate fraction, with reported LC 50 values of 50.18 and 48.73 μg/ml respectively. Conversely, methanol extracts were not that toxic to the A549 cell line though the toxicity increased on further purification. The percentage of growth inhibition was dose dependent for the methanol extract and ethyl acetate fraction. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The results showed that methanol extracts of plant seeds caused 100% mortality of mosquito larvae at a concentration of 1000 μg/ml after 24 h of treatment. The LC 50 and LC 90 values of X. strumarium were found to be 531.07 and 905.95 μg/ml against Ae. caspius and 502.32 and 867.63 μg/ml against Cx. Pipiens, respectively. From the investigations, it was concluded that the crude extract of X. strumarium showed a weak potential for controlling the larval instars of Ae. caspius and Cx. pipiens . However, on further purification the extract lost the larvicidal activity. The ethyl acetate fraction showed higher toxicity to all cell lines tested when compared to the methanol extract. The ethyl acetate fraction investigated in this study appears to have a weak larvicidal activity but a promising cytotoxic activity. Future studies will include purification and investigation in further detail of the action of X. strumarium on Cancer Cell Lines and mosquitoes.

  6. Field evaluation of spatial repellency of metofluthrin impregnated plastic strips against mosquitoes in Hai Phong City, Vietnam.

    Science.gov (United States)

    Kawada, Hitoshi; Yen, Nguyen Thi; Hoa, Nguyen Thuy; Sang, Truong Minh; VAN Dan, Nguyen; Takagi, Masahiro

    2005-08-01

    Spatial repellency of metofluthrin-impregnated polyethylene plastic strips against mosquitoes, Aedes aegypti and Culex quinquefasciatus, were studied in a residential area in Hai Phong city, Vietnam. Thirty houses were selected as trial sites; half of these were assigned as untreated control and the other half were assigned for treatment. Primarily, irrespective of the room size, one room was treated with one strip. The dominant species in the trial sites were Culex quinquefasciatus and Aedes aegypti. A rapid decrease in the mosquito index was observed immediately after the treatment with metofluthrin strips, and treatment was effective for at least 6 weeks.

  7. Micro x-ray absorption spectroscopic analysis of arsenic localization and biotransformation in Chironomus riparius Meigen (Diptera: Chironomidae) and Culex tarsalis Coquillett (Culicidae)

    International Nuclear Information System (INIS)

    Mogren, Christina L.; Webb, Samuel M.; Walton, William E.; Trumble, John T.

    2013-01-01

    The distribution and speciation of arsenic (As) were analyzed in individuals of various life stages of a midge, Chironomus riparius, and the mosquito Culex tarsalis exposed to 1000 μg/l arsenate. X-ray absorption spectroscopy (XAS) revealed that C. riparius larvae accumulate As in their midgut, with inorganic arsenate [As(V)] being the predominant form, followed by arsenite [As(III)] and an As-thiol. Reduced concentrations of As in pupal and adult stages of C. riparius indicate excretion of As between the larval and pupal stages. In adults, As was limited to the thorax, and the predominant form was an As-thiol. In Cx. tarsalis, As was not found in high enough concentrations to determine As speciation, but the element was distributed throughout the larva. In adults, As was concentrated in the thorax and eyes of adults. These results have implications for understanding the biotransformation of As and its movement from aquatic to terrestrial environments. -- Highlights: •C. riparius larvae reduced arsenate to arsenite in the midgut. •C. riparius larvae accumulated As in the midgut, with 27% as a transformed As-thiol. •C. riparius adults retained As in the thorax, with 53% as As-thiol. •Larvae of Cx. tarsalis did not have a specific site of As accumulation. •Low concentrations of As in adults suggest reduced terrestrial transfer potential. -- Arsenic accumulation and biotransformation in aquatic insects is variable, but the location and speciation of As provides insight into the detoxification mechanisms of aquatic Diptera

  8. Entomologic investigations during an outbreak of West Nile virus disease in Maricopa County, Arizona, 2010.

    Science.gov (United States)

    Godsey, Marvin S; Burkhalter, Kristen; Young, Ginger; Delorey, Mark; Smith, Kirk; Townsend, John; Levy, Craig; Mutebi, John-Paul

    2012-12-01

    Entomologic investigations were conducted during an intense outbreak of West Nile virus (WNV) disease in Maricopa County, Arizona during July 31-August 9, 2010. The investigations compared the East Valley outbreak area, and a demographically similar control area in northwestern metropolitan Phoenix where no human cases were reported. Five mosquito species were identified in each area, and species composition was similar in both areas. Significantly more Culex quinquefasciatus females were collected by gravid traps at Outbreak sites (22.2 per trap night) than at control sites (8.9 per trap night), indicating higher Cx. quinquefasciatus abundance in the outbreak area. Twenty-eight WNV TaqMan reverse transcription-polymerase chain reaction-positive mosquito pools were identified, including 24 of Cx. quinquefasciatus, 3 of Psorophora columbiae, and 1 of Culex sp. However, Cx. quinquefasciatus WNV infection rates did not differ between outbreak and control sites. At outbreak sites, 30 of 39 engorged Cx. quinquefasciatus had fed on birds, 8 of 39 on humans, and 1 of 39 on a lizard. At control sites, 20 of 20 identified blood meals were from birds. Data suggest that Cx. quinquefasciatus was the primary enzootic and epidemic vector of this outbreak. The most important parameters in the outbreak were vector abundance and blood meal analysis, which suggested more frequent contact between Cx. quinquefasciatus and human hosts in the outbreak area compared with the control area.

  9. Molecular identification of two Culex (Culex species of the neotropical region (Diptera: Culicidae.

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    Magdalena Laurito

    Full Text Available Culex bidens and C. interfor, implicated in arbovirus transmission in Argentina, are sister species, only distinguishable by feature of the male genitalia; however, intermediate specimens of the species in sympatry have been found. Fourth-instar larvae and females of both species share apomorphic features, and this lack of clear distinction creates problems for specific identification. Geometric morphometric traits of these life stages also do not distinguish the species. The aim of the present study was to assess the taxonomic status of C. bidens and C. interfor using two mitochondrial genes and to determine the degree of their reproductive isolation using microsatellite loci. Sequences of the ND4 and COI genes were concatenated in a matrix of 993 nucleotides and used for phylogenetic and distance analyses. Bayesian and maximum parsimony inferences showed a well resolved and supported topology, enclosing sequences of individuals of C. bidens (0.83 BPP, 73 BSV and C. interfor (0.98 BPP, 97 BSV in a strong sister relationship. The mean K2P distance within C. bidens and C. interfor was 0.3% and 0.2%, respectively, and the interspecific variation was 2.3%. Bayesian clustering also showed two distinct mitochondrial lineages. All sequenced mosquitoes were successfully identified in accordance with the best close match algorithm. The low genetic distance values obtained indicate that the species diverged quite recently. Most morphologically intermediate specimens of C. bidens from Córdoba were heterozygous for the microsatellite locus GT51; the significant heterozygote excess observed suggests incomplete reproductive isolation. However, C. bidens and C. interfor should be considered good species: the ventral arm of the phallosome of the male genitalia and the ND4 and COI sequences are diagnostic characters.

  10. St. Louis Encephalitis virus mosquito vectors dynamics in three different environments in relation to remotely sensed environmental conditions.

    Science.gov (United States)

    Batallán, Gonzalo P; Estallo, Elizabet L; Flores, Fernando S; Sartor, Paolo; Contigiani, Marta S; Almirón, Walter R

    2015-06-01

    In Argentina the St. Louis Encephalitis virus (SLEV) is an endemic and widely distributed pathogen transmitted by the cosmopolitan mosquito Culex quinquefasciatus. During two outbreaks in Córdoba city, in 2005 and 2010, Culex interfor was also found infected, but its role as vector of SLEV is poorly known. This mosquito species is distributed from central Argentina to southern Brazil. The primary aim of this study was to analyze the population dynamic of Cx. interfor and Cx. quinquefasciatus in three different environments (urban, suburban and non-urban) in relation to remotely sensed environmental data for vegetation (NDVI and NDWI) and temperature (brightness temperature). Cx. quinquefasciatus and Cx. interfor were found at the three sampled sites, being both the most abundant Culex species, with peaks in early and midsummer. Temporal distribution patterns of both mosquito species were highly correlated in a non-urban area of high SLEV risk transmission. Cx. quinquefasciatus and Cx. interfor were associated with the most urbanized site and the non-urban environment, respectively; high significant correlations were detected between vegetation indices and abundance of both mosquito species confirming these associations. These data provide a foundation for building density maps of these two SLEV mosquito vectors using remotely sensed data to help inform vector control programs. Copyright © 2015 Elsevier B.V. All rights reserved.

  11. Preferencia de hospedadores de Culicidae (Diptera recolectados en el centro de la Argentina

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    Almirón Walter R.

    1995-01-01

    Full Text Available Con el propósito de estudiar la preferencia de hospedadores vertebrados por mosquitos hembras, durante 2 períodos octubre-abril (primavera-verano, se realizaron muestreos cada 15 días en Córdoba y Cosquín (Argentina. Se utilizaron trampas de latón con cebo animal: anfibios (sapos, aves (pollos, mamíferos (conejos y reptiles (tortugas. El 92,9% de los especímenes recolectados pertenecen al género Culex, mientras que un 7,0% corresponde a Aedes y el 0,02% restante a Psorophora ciliata, única especie que se capturó de ese género. En trampas con pollo se recolectó el mayor número de hembras (68,7%, siguiendo en orden las trampas con conejos (29,9%, con tortugas (0,8% y con sapos (0,5%, por lo tanto, la mayoría de los mosquitos entraron en las trampas con hospedadores homeotermos. Culex dolosus se alimentó sobre todos los cebos, mientras que Cx. acharistus, Cx. chidesteri y Cx. quinquefasciatus se alimentaron sobre pollos, conejos y tortugas; Ae. albifasciatus, Ae. scapularis, Cx. bidens y Cx. coronator lo hicieron sobre ambos hospedadores homeotermos; Cx. apicinus, Cx. maxi, Cx. saltanensis y Cx. spinosus se alimentaron solamente sobre pollos y Ps. ciliata sobre conejos.

  12. Essential Oils of Satureja Species: Insecticidal Effect on Culex pipiens Larvae (Diptera: Culicidae

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    Nikos G. Chorianopoulos

    2007-12-01

    Full Text Available The chemical composition of the essential oils of the wild growing plants of Greek S. spinosa L., S. parnassica subsp. parnassica Heldr.& Sart ex Boiss., S. thymbra and S. montana were determined by GC and GC/MS analysis. The larvicidal activities of the essential oils were assayed against Culex pipiens biotype molestus. The analytical data indicated that various monoterpene hydrocarbons and phenolic monoterpenes constitute the major constituents of the oils, but their concentration varied greatly among the oils examined. The bioassay results indicated that the oils possess significant larvicidal activities and represent an inexpensive source of natural substances mixture that exhibit potentials for use to control the mosquito larvae.

  13. Species Composition and Ecological Aspects of Immature Mosquitoes (Diptera: Culicidae in Bromeliads in Urban Parks in the City of São Paulo, Brazil

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    Walter Ceretti-Junior

    2015-10-01

    Full Text Available Background: Bromeliads can be epiphytic, terrestrial or saxicolous and use strategies to allow water to be re­tained in their leaf axils, where various arthropods can be found. These include mosquitoes, whose larvae are the most abundant and commonly found organisms in the leaf axils. The objective of this study was to look for im­mature forms of mosquitoes (the larval and pupal stages in bromeliads in municipal parks in São Paulo and to discuss the ecological and epidemiological importance of these insects.Methods: From October 2010 to July 2013, immature mosquitoes were collected from bromeliads in 65 munici­pal parks in the city of São Paulo, Brazil, using suction samplers. The immature forms were maintained until adult forms emerged, and these were then identified morphologically.Results: Two thousand forty-two immature-stage specimens belonging to the genera Aedes, Culex, Trichoprosopon, Toxorhynchites, Limatus and Wyeomyia were found in bromeliads in 15 of the 65 parks visited. Aedes albopictus was the most abundant species (660 specimens collected, followed by Culex quinquefasciatus (548 specimens and Cx. (Microculex imitator (444. The taxa with the most widespread distribution were Ae. aegypti and Toxorhynchites spp, followed by Ae. albopictus and Cx. quinquefasciatus.Conclusion: Bromeliads in urban parks are refuges for populations of native species of Culicidae and breeding sites for exotic species that are generally of epidemiological interest. Hence, administrators and surveillance and mosquito-control agencies must constantly monitor these microenvironments as the presence of these species endangers the health of park users and employees as well as people living near the parks. 

  14. Entomologic investigations of an epidemic of St. Louis encephalitis in Pine Bluff, Arkansas, 1991.

    Science.gov (United States)

    Savage, H M; Smith, G C; Moore, C G; Mitchell, C J; Townsend, M; Marfin, A A

    1993-07-01

    An epidemic of St. Louis encephalitis (SLE) occurred in Jefferson County, Arkansas during July-August 1991. At least 26 human cases were involved, with 25 cases in the town of Pine Bluff. Twelve isolates of SLE virus were obtained from mosquitoes collected in Pine Bluff between August 13 and 24: 11 from pools of Culex pipiens quinquefasciatus, resulting in a minimum infection rate of 1.6 per 1,000 (n = 6,768) for this subspecies, and one isolate from a pool of 22 mosquitoes identified as Cx. (Culex) spp. Three of the SLE-positive pools, two from Cx. p. quinquefasciatus and one from Cx. (Cux.) spp., also yielded isolates of Flanders virus. Larval surveys resulted in the collection of seven species in four genera from 28 larva-positive habitats and the identification of one significant site of Cx. p. quinquefasciatus production. Ecologic assessments conducted at 12 randomly selected residences resulted in the identification of 17 larva-positive habitats, for an average mosquito-positive habitat rate of 1.4 per residence, and a Cx. p. quinquefasciatus larva-positive habitat rate of 0.6 per residence. Aedes albopictus and Cx. p. quinquefasciatus were the species most frequently encountered in larval surveys in residential neighborhoods.

  15. An updated checklist of the Culicidae (Diptera) of Morocco, with notes on species of historical and current medical importance.

    Science.gov (United States)

    Trari, Bouchra; Dakki, Mohamed; Harbach, Ralph E

    2017-06-01

    An updated checklist of the mosquito species (Diptera: Culicidae) recorded in Morocco from 1916 to 2016 is provided, including synonyms and synonymous usage for each species. Forty-three species belonging to seven genera are recorded so far: Anopheles (9), Aedes (12) Coquillettidia (2), Culex (12), Culiseta (5), Orthopodomyia (1) and Uranotaenia (2). Traditional and equivalent names in the polyphyletic concept of Aedes are provided for the aedine species. The historical importance and current potential threat of mosquitoes to human health in Morocco is reviewed. © 2017 The Society for Vector Ecology.

  16. Culex pipiens and Stegomyia albopicta (= Aedes albopictus) populations as vectors for lineage 1 and 2 West Nile virus in Europe.

    Science.gov (United States)

    Brustolin, M; Talavera, S; Santamaría, C; Rivas, R; Pujol, N; Aranda, C; Marquès, E; Valle, M; Verdún, M; Pagès, N; Busquets, N

    2016-06-01

    The emerging disease West Nile fever is caused by West Nile virus (WNV), one of the most widespread arboviruses. This study represents the first test of the vectorial competence of European Culex pipiens Linnaeus 1758 and Stegomyia albopicta (= Aedes albopictus) (both: Diptera: Culicidae) populations for lineage 1 and 2 WNV isolated in Europe. Culex pipiens and S. albopicta populations were susceptible to WNV infection, had disseminated infection, and were capable of transmitting both WNV lineages. This is the first WNV competence assay to maintain mosquito specimens under environmental conditions mimicking the field (day/night) conditions associated with the period of maximum expected WNV activity. The importance of environmental conditions is discussed and the issue of how previous experiments conducted in fixed high temperatures may have overestimated WNV vector competence results with respect to natural environmental conditions is analysed. The information presented should be useful to policymakers and public health authorities for establishing effective WNV surveillance and vector control programmes. This would improve preparedness to prevent future outbreaks. © 2016 The Authors. Medical and Veterinary Entomology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.

  17. Inhibition and Larvicidal Activity of Phenylpropanoids from Piper sarmentosum on Acetylcholinesterase against Mosquito Vectors and Their Binding Mode of Interaction.

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    Arshia Hematpoor

    Full Text Available Aedes aegypti, Aedes albopictus and Culex quinquefasciatus are vectors of dengue fever and West Nile virus diseases. This study was conducted to determine the toxicity, mechanism of action and the binding interaction of three active phenylpropanoids from Piper sarmentosum (Piperaceae toward late 3rd or early 4th larvae of above vectors. A bioassay guided-fractionation on the hexane extract from the roots of Piper sarmentosum led to the isolation and identification of three active phenylpropanoids; asaricin 1, isoasarone 2 and trans-asarone 3. The current study involved evaluation of the toxicity and acetylcholinesterase (AChE inhibition of these compounds against Aedes aegypti, Aedes albopictus and Culex quinquefasciatus larvae. Asaricin 1 and isoasarone 2 were highly potent against Aedes aegypti, Aedes albopictus and Culex quinquefasciatus larvae causing up to 100% mortality at ≤ 15 μg/mL concentration. The ovicidal activity of asaricin 1, isoasarone 2 and trans-asarone 3 were evaluated through egg hatching. Asaricin 1 and isoasarone 2 showed potent ovicidal activity. Ovicidal activity for both compounds was up to 95% at 25μg/mL. Asaricin 1 and isoasarone 2 showed strong inhibition on acetylcholinesterase with relative IC50 values of 0.73 to 1.87 μg/mL respectively. These findings coupled with the high AChE inhibition may suggest that asaricin 1 and isoasarone 2 are neuron toxic compounds toward Aedes aegypti, Aedes albopictus and Culex quinquefasciatus. Further computational docking with Autodock Vina elaborates the possible interaction of asaricin 1 and isoasarone 2 with three possible binding sites of AChE which includes catalytic triads (CAS: S238, E367, H480, the peripheral sites (PAS: E72, W271 and anionic binding site (W83. The binding affinity of asaricin 1 and isoasarone 2 were relatively strong with asaricin 1 showed a higher binding affinity in the anionic pocket.

  18. Inhibition and Larvicidal Activity of Phenylpropanoids from Piper sarmentosum on Acetylcholinesterase against Mosquito Vectors and Their Binding Mode of Interaction.

    Science.gov (United States)

    Hematpoor, Arshia; Liew, Sook Yee; Chong, Wei Lim; Azirun, Mohd Sofian; Lee, Vannajan Sanghiran; Awang, Khalijah

    2016-01-01

    Aedes aegypti, Aedes albopictus and Culex quinquefasciatus are vectors of dengue fever and West Nile virus diseases. This study was conducted to determine the toxicity, mechanism of action and the binding interaction of three active phenylpropanoids from Piper sarmentosum (Piperaceae) toward late 3rd or early 4th larvae of above vectors. A bioassay guided-fractionation on the hexane extract from the roots of Piper sarmentosum led to the isolation and identification of three active phenylpropanoids; asaricin 1, isoasarone 2 and trans-asarone 3. The current study involved evaluation of the toxicity and acetylcholinesterase (AChE) inhibition of these compounds against Aedes aegypti, Aedes albopictus and Culex quinquefasciatus larvae. Asaricin 1 and isoasarone 2 were highly potent against Aedes aegypti, Aedes albopictus and Culex quinquefasciatus larvae causing up to 100% mortality at ≤ 15 μg/mL concentration. The ovicidal activity of asaricin 1, isoasarone 2 and trans-asarone 3 were evaluated through egg hatching. Asaricin 1 and isoasarone 2 showed potent ovicidal activity. Ovicidal activity for both compounds was up to 95% at 25μg/mL. Asaricin 1 and isoasarone 2 showed strong inhibition on acetylcholinesterase with relative IC50 values of 0.73 to 1.87 μg/mL respectively. These findings coupled with the high AChE inhibition may suggest that asaricin 1 and isoasarone 2 are neuron toxic compounds toward Aedes aegypti, Aedes albopictus and Culex quinquefasciatus. Further computational docking with Autodock Vina elaborates the possible interaction of asaricin 1 and isoasarone 2 with three possible binding sites of AChE which includes catalytic triads (CAS: S238, E367, H480), the peripheral sites (PAS: E72, W271) and anionic binding site (W83). The binding affinity of asaricin 1 and isoasarone 2 were relatively strong with asaricin 1 showed a higher binding affinity in the anionic pocket.

  19. Comparative susceptibility of introduced forest-dwelling mosquitoes in Hawai'i to avian malaria, Plasmodium relictum

    Science.gov (United States)

    Lapointe, D.A.; Goff, M.L.; Atkinson, C.T.

    2005-01-01

    To identify potential vectors of avian malaria in Hawaiian native forests, the innate susceptibility of Aedes albopictus, Wyeomyia mitchellii, and Culex quinquefasciatus from 3 geographical sites along an altitudinal gradient was evaluated using local isolates of Plasmodium relictum. Mosquitoes were dissected 5-8 and 9-13 days postinfective blood meal and microscopically examined for oocysts and salivary-gland sporozoites. Sporogony was completed in all 3 species, but prevalence between species varied significantly. Oocysts were detected in 1-2% and sporozoites in 1-7% of Aedes albopictus that fed on infected ducklings. Wyeomyia mitchellii was slightly more susceptible, with 7-19% and 7% infected with oocysts and sporozoites, respectively. In both species, the median oocyst number was 5 or below. This is only the second Wyeomyia species reported to support development of a malarial parasite. Conversely, Culex quinquefasciatus from all 3 sites proved very susceptible. Prevalence of oocysts and sporozoites consistently exceeded 70%, regardless of gametocytemia or origin of the P. relictum isolate. In trials for which a maximum 200 oocysts were recorded, the median number of oocysts ranged from 144 to 200. It was concluded that Culex quinquefasciatus is the primary vector of avian malaria in Hawai'i. ?? American Society of Parasitologists 2005.

  20. Chemical composition, toxicity and non-target effects of Pinus kesiya essential oil: An eco-friendly and novel larvicide against malaria, dengue and lymphatic filariasis mosquito vectors.

    Science.gov (United States)

    Govindarajan, Marimuthu; Rajeswary, Mohan; Benelli, Giovanni

    2016-07-01

    Mosquitoes (Diptera: Culicidae) are vectors of important parasites and pathogens causing death, poverty and social disability worldwide, with special reference to tropical and subtropical countries. The overuse of synthetic insecticides to control mosquito vectors lead to resistance, adverse environmental effects and high operational costs. Therefore, the development of eco-friendly control tools is an important public health challenge. In this study, the mosquito larvicidal activity of Pinus kesiya leaf essential oil (EO) was evaluated against the malaria vector Anopheles stephensi, the dengue vector Aedes aegypti and the lymphatic filariasis vector Culex quinquefasciatus. The chemical composition of the EO was analyzed by gas chromatography-mass spectroscopy. GC-MS revealed that the P. kesiya EO contained 18 compounds. Major constituents were α-pinene, β-pinene, myrcene and germacrene D. In acute toxicity assays, the EO showed significant toxicity against early third-stage larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus, with LC50 values of 52, 57, and 62µg/ml, respectively. Notably, the EO was safer towards several aquatic non-target organisms Anisops bouvieri, Diplonychus indicus and Gambusia affinis, with LC50 values ranging from 4135 to 8390µg/ml. Overall, this research adds basic knowledge to develop newer and safer natural larvicides from Pinaceae plants against malaria, dengue and filariasis mosquito vectors. Copyright © 2016 Elsevier Inc. All rights reserved.

  1. In vivo binding of the Cry11Bb toxin of Bacillus thuringiensis subsp. medellin to the midgut of mosquito larvae (Diptera: Culicidae

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    Ruiz Lina María

    2004-01-01

    Full Text Available Bacillus thuringiensis subsp. medellin produces numerous proteins among which 94 kDa known as Cry11Bb, has mosquitocidal activity. The mode of action of the Cry11 proteins has been described as similar to those of the Cry1 toxins, nevertheless, the mechanism of action is still not clear. In this study we investigated the in vivo binding of the Cry11Bb toxin to the midgut of the insect species Anopheles albimanus, Aedes aegypti, and Culex quinquefasciatus by immunohistochemical analysis. Spodoptera frugiperda was included as negative control. The Cry11Bb protein was detected on the apical microvilli of the midgut epithelial cells, mostly on the posterior midgut and gastric caeca of the three mosquito species. Additionally, the toxin was detected in the Malpighian tubules of An. albimanus, Ae. aegypti, Cx. quinquefasciatus, and in the basal membrane of the epithelial cells of Ae. aegypti midgut. No toxin accumulation was observed in the peritrophic membrane of any of the mosquito species studied. These results confirm that the primary site of action of the Cry11 toxins is the apical membrane of the midgut epithelial cells of mosquito larvae.

  2. Evaluation of organophosphorus and synthetic pyrethroid insecticides against six vector mosquitoe species Avaliação de inseticidas organofosforados e piretroides sintéticos contra seis mosquitos vetores

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    Domingo Montada Dorta

    1993-12-01

    Full Text Available Three organophosphorus compounds- malathion, folithion and temephos- and two synthetic pyrethroids- alphamethrin and deltamethrin- were used for monitoring the susceptibility status of larvae and adults of six vector mosquitoe species: Culex quinquefasciatus (Filariasis and Aedes albopictus (Dengue (both laboratory and field strains; laboratory strains of Aedes aegypti (Dengue, Anopheles slephensi and Anopheles culicifacies (Malaria, and Culex tritaeniorhynchus (Japanese encephalitis in India. From the LC50 values obtained for these insecticides, it was found that all mosquito species including the field strains of Cx. quinquefasciatus and Ae. albopictus were highly susceptible Except for Cx. quinquefasciatus (field strain against malathion, 100% mortality was observed at the discriminating dosages recommended by World Health Organization. The residual effect of alphamethrin, deltamethrin, malathion and folithion at 25 mg (ai/m² on different surfaces against six species of vector mosquitoes showed that alphamethrin was the most effective on all four treated surfaces (mud, plywood, cement and thatch. Nevertheless, residual efficacy lasted longer on thatch than on the other surfaces. Therefore, synthetic pyrethroids such as alphamethrin can be effectively employed in integrated vector control operations.Três compostos organo-fosforados - malation, folition e temefos -e dois piretroides sintéticos - alfametrina e deltametrina - foram usados para controlar o estado da susceptibilidade das larvas e adultos de seis mosquitos vetores na Índia. Foram utilizadas cepas de laboratório e área de Culex quinquefasciatus (filariasis e Aedes albopictus (Dengue e cepas de laboratório de Aedes aegypti (Dengue, Anopheles stephensi e Anopheles culicifacies (Malária e Culex tritaenorhynchus (encefalite japonesa. Os valores de C1(50 obtidos para esses inseticidas mostram que todas as espécies incluindo as cepas de área foram muito susceptíveis. Nos

  3. Evaluation of a Field-Portable DNA Microarray Platform and Nucleic Acid Amplification Strategies for the Detection of Arboviruses, Arthropods, and Bloodmeals

    Science.gov (United States)

    2013-01-01

    heparin was purchased from Innovative Research (Novi, MI). Goat and horse whole blood was provided by our Veterinary Medicine Division (USAMRIID, Fort...quinquefasciatus (10) BA House NA Human Culex Th9-0122 Ae. aegypti (1) BA House DENV-3 DNP Aedes Th9-0164 Cx. tritaeniorhynchus (24) LT Farm JEV NA...Culex Th9-0167 Ae. albopictus (1) LT Farm NA NA Aedes Th9-0175 Cx. tritaeniorhynchus (25) LT Farm JEV NA Culex Th9-0235 Cx. tritaeniorhynchus (25) BA

  4. Observações sobre os mosquitos Culex da cidade de São Paulo, Brasil Observations on Culex mosquitoes of S. Paulo City, Brazil

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    Oswaldo Paulo Forattini

    1973-12-01

    Full Text Available São apresentados os resultados obtidos na coleta de mosquitos do gênero Culex na área urbana da cidade de São Paulo, Brasil. Foram empregadas armadilhas luminosas automáticas tipo "New Jersey 50". Os resultados revelaram a presença de outras populações representadas principalmente por Culex chidesteri, C. dolosus e C. bidens as quais, em conjunto, chegaram algumas vezes a sobrepujar a de Culex pipiens fatigans. O maior rendimento foi obtido em áreas com abastecimento de água mas sem rede de esgotos. As coletas intradomiciliares revelaram franca predominância de C. pipiens fatigans.With the use of New Jersey-50 light traps, a survey of Culex mosquitoes was made in the urban área of São Paulo City, Brazil. Beside Culex pipiens fatigans several other species were found, mainly represented by Culex chidesteri, C. dolosus and C. bidens. The combined incidence of these three populations follows nearly the fatigans one and frequently exceeding it. The most high levels of density were found at areas with water treatment but without sewage disposal. Domiciliary collections showed great Culex pipiens fatigans predominancy.

  5. Predation and control efficacies of Misgurnus mizolepis (Cypriniformes: Cobitidae) toward Culex pipiens molestus (Diptera: Culicidae) and fish toxicity of temephos in laboratory and septic tank conditions.

    Science.gov (United States)

    Chae, Seong Chun; Kwon, Young Hyun; Min, Kyung Il; Kim, Hyung Soo; Kim, Nam-Jin; Kim, Jun-Ran; Son, Bong Gi; Ahn, Young-Joon

    2014-07-01

    Culex pipiens molestus Forskal (Diptera: Culicidae) is the dominant mosquito species in septic tanks in South Korea. An assessment was made of the biological control potential of mud loaches, Misgurnus mizolepis Günther (Cypriniformes: Cobitidae), toward Cx. p. molestus larvae in laboratory and septic tanks. Results were compared with those of temephos 20% emulsifiable concentrate. In laboratory tests, all mud loaches survived on sedimentation chamber- and effluent chamber-collected water of aerobic septic tanks (ASTs), whereas all mud loaches died within 3-12 h after introduction into sedimentation chamber- and effluent chamber-collected water of anaerobic septic tanks, Gill hyperplasia and hemorrhages at the bases of pectoral fins were detected in all dead mud loaches. These appeared to have been caused by bacterial disease, rather than the physical and chemical characteristics of the septic tank water. A mud loach consumed an average range of 1,072-1,058 larvae of Cx. p. molestus in the AST water at 24 h. At the manufacturer's recommended rate (10 ml/ton) in the AST water, the temephos formulation did not cause fish mortality. In the AST experiment, predation of mosquito larvae by mud loaches at a release rate of one fish per 900 mosquito larvae resulted in complete mosquito control from the third day after treatment throughout the 18-wk survey period, compared with temephos 20% emulsifiable concentrate-treated AST water (reduction rate, 40% at 28 days after treatment). Reasonable mosquito control in aerobic septic tanks can be achieved by mosquito breeding season stocking of a rate of one mud loach per 900 mosquito larvae.

  6. Mosquito ovicidal properties of Ageratina adenophora (Family: Asteraceae) against filariasis vector, Culex quinquefasciatus (Diptera: Culicidae)

    Science.gov (United States)

    Mosquito-borne diseases with an economic impact create loss in commercial and labor outputs, particularly in countries with tropical and subtropical climates. Mosquito control is facing a threat because of the emergence of resistance to synthetic insecticides. Extracts from plants may be alternativ...

  7. Hydrological modeling of geophysical parameters of arboviral and protozoan disease vectors in Internally Displaced People camps in Gulu, Uganda.

    Science.gov (United States)

    Jacob, Benjamin G; Muturi, Ephantus J; Caamano, Erick X; Gunter, James T; Mpanga, Enoch; Ayine, Robert; Okelloonen, Joseph; Nyeko, Jack Pen-Mogi; Shililu, Josephat I; Githure, John I; Regens, James L; Novak, Robert J; Kakoma, Ibulaimu

    2008-03-14

    The aim of this study was to determine if remotely sensed data and Digital Elevation Model (DEM) can test relationships between Culex quinquefasciatus and Anopheles gambiae s.l. larval habitats and environmental parameters within Internally Displaced People (IDP) campgrounds in Gulu, Uganda. A total of 65 georeferenced aquatic habitats in various IDP camps were studied to compare the larval abundance of Cx. quinquefasciatus and An. gambiae s.l. The aquatic habitat dataset were overlaid onto Land Use Land Cover (LULC) maps retrieved from Landsat imagery with 150 m x 150 m grid cells stratified by levels of drainage. The LULC change was estimated over a period of 14 years. Poisson regression analyses and Moran's I statistics were used to model relationships between larval abundance and environmental predictors. Individual larval habitat data were further evaluated in terms of their covariations with spatial autocorrelation by regressing them on candidate spatial filter eigenvectors. Multispectral QuickBird imagery classification and DEM-based GIS methods were generated to evaluate stream flow direction and accumulation for identification of immature Cx. quinquefasciatus and An. gambiae s.l. and abundance. The main LULC change in urban Gulu IDP camps was non-urban to urban, which included about 71.5 % of the land cover. The regression models indicate that counts of An. gambiae s.l. larvae were associated with shade while Cx. quinquefasciatus were associated with floating vegetation. Moran's I and the General G statistics for mosquito density by species and instars, identified significant clusters of high densities of Anopheles; larvae, however, Culex are not consistently clustered. A stepwise negative binomial regression decomposed the immature An. gambiae s.l. data into empirical orthogonal bases. The data suggest the presence of roughly 11% to 28 % redundant information in the larval count samples. The DEM suggest a positive correlation for Culex (0.24) while for

  8. Efficacy of larvicidal activity of green synthesized titanium dioxide nanoparticles using Mangifera indica extract against blood-feeding parasites.

    Science.gov (United States)

    Rajakumar, Govindasamy; Rahuman, Abdul Abdul; Roopan, Selvaraj Mohana; Chung, Ill-Min; Anbarasan, Karunanithi; Karthikeyan, Viswanathan

    2015-02-01

    Titanium dioxide nanoparticles (TiO2 NPs) are considered to be among the best photocatalytic materials due to their long-term thermodynamic stability, strong oxidizing power, and relative non-toxicity. Nano-preparations with TiO2 NPs are currently under investigation as novel treatments for acne vulgaris, recurrent condyloma acuminata, atopic dermatitis, hyperpigmented skin lesions, and other non-dermatologic diseases. The present study was to investigate the acaricidal and larvicidal activity of synthesized TiO2 NPs utilizing leaf aqueous extract of Mangifera indica L. (Anacardiaceae) against hematophagous parasites. The anti-parasitic activity of TiO2 NPs against the larvae of Rhipicephalus (Boophilus) microplus, Hyalomma anatolicum anatolicum and Haemaphysalis bispinosa (Acari: Ixodidae), fourth instar larvae of Anopheles subpictus, and Culex quinquefasciatus (Diptera: Culicidae) were assessed. The green synthesized TiO2 NPs were analyzed by UV-Vis, FTIR, X-ray diffraction (XRD), AFM, SEM, and TEM. The XRD analysis of synthesized TiO2 NPs revealed the dominant peak at 2θ value of 27.81 which matched the 110 crystallographic plane of the rutile structure indicating the crystal structure. The FTIR spectra exhibited a prominent peak at 3,448 cm(-1) and showed OH stretching due to the alcoholic group, and the OH group may act as a capping agent. The SEM images of TiO2 NPs displayed spherical, oval in shape, individual, and some in aggregates. Characterization of the synthesized TiO2 NPs using AFM offered three-dimensional visualization and uneven surface morphology. The TEM micrograph showed agglomerates, round and slight elongation with an average size of 30 ± 5 nm. The maximum efficacy was observed in synthesized TiO2 NPs against the larvae of R. microplus, Hyalomma anatolicum anatolicum, Haemaphysalis bispinosa, A. subpictus, and Culex quinquefasciatus with LC50 value of 28.56, 33.17, 23.81, 5.84, and 4.34 mg/L, respectively. In the present study, a novel

  9. The Ecological Aspects of Culex pipiens (Diptera: Culicidae in Central Iran.

    Directory of Open Access Journals (Sweden)

    Hossein Dehghan

    2014-06-01

    Full Text Available The aim was to survey the specific factors, which cause to decrease blood feeding of mosquitoes important to succeed vector control.Larval collection was carried out from fixed and variable breeding places of Yazd County, central Iran in 2009. Autogeny-Anautogeny, Stenogamy-Eurygamy, and blood preference of Culex pipiens were studied using standard mosquito cages blood meal source for Cx. pipiens females considered as the chickens and human and fed females were kept in insectary condition (16:8 L: D, 27±3 °C and 70±10% RH. The data were analyzed using SPSS Ver. 11.5 soft ware.Totally, 96 females' mosquitoes were tested for Stenogamy versus Eurygamy and 122 for blood preference assay. In the small cages (20 × 20 × 20cm and large cage (60 × 40 × 60cm, the ability of mating and insemination rates were 60.0 and 67.0%, respectively. In spite of Cx. pipiens fed from sucrose 5%, none of them laying eggs in 60 × 40 × 60 cages during the study. This finding indicated the Anautogeny behavior of this species. This species was found of low tendency to human blood and almost 4 fold fed on chicken.The occurrence of Steno-Eurygamy, Anautogeny, and Ornithophilic behaviors of Cx. Pipiens was noted. More studies need to be carried out about the bionomics of this species to gain more data about the ecophysiological and behavioral characteristics in other parts of Iran.

  10. EST Table: FS914945 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS914945 E_FL_fufe_33M09_F_0 10/09/28 36 %/210 aa ref|XP_001842174.1| sensitized chromosome inheritance... modifier 19 [Culex quinquefasciatus] gb|EDS39679.1| sensitized chromosome inheritance m

  11. EST Table: FS918359 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS918359 E_FL_fufe_44C07_F_0 10/09/28 37 %/227 aa ref|XP_001842174.1| sensitized chromosome inheritance... modifier 19 [Culex quinquefasciatus] gb|EDS39679.1| sensitized chromosome inheritance m

  12. The effects of forced-egg retention on the blood-feeding behavior and reproductive potential of Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Johnson, Brian J; Fonseca, Dina M

    2014-07-01

    High rates of West Nile virus (WNV) transmission to humans are associated with exceptionally hot and dry summers. This is paradoxical since the eggs of Culex vectors of WNV depend on the persistence of containers with water, which decline during droughts. We examined the effects of forced-egg retention on the reproductive success of female Culex pipiens as well as behavioral responses, such as likelihood of secondary blood meals. As controls we examined the effects of female age and delayed mating. We found that early mating is essential to achieve reproductive success and, consistent with an "all-or-none" ovipositing strategy, C. pipiens females are able to retain considerable reproductive potential while searching for oviposition sites. Specifically, although forced-egg retention resulted in significant decreases in fitness, the decline was moderate for 5 weeks and most can be accounted for by increases in female age. Consequently, no females took blood more than once per gonotrophic cycle, which eliminates the possibility that heightened vectorial capacity due to multiple blood-feedings increases WNV transmission during periods of drought. Instead, our findings suggest that during droughts populations of C. pipiens have time to locate the remaining water holes, which are associated with human populations and WNV-competent bird species. Copyright © 2014. Published by Elsevier Ltd.

  13. 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......,132 water samples from WSP and irrigated areas yielded 606,053 Culex larvae of five species. In addition, 107,113 anophelines, representing eight species were collected. Anopheles subpictus (Grassi) and Culex mosquitoes, especially Culex quinquefasciatus (Say) and Culex tritaeniorhynchus (Giles), showed...... an overwhelming preference for anaerobic ponds, which receive untreated wastewater. Facultative ponds generated lower numbers of both Anopheles and Culex mosquitoes, whereas the last ponds in the series, the maturation ponds, were the least productive for both mosquito genera. An. subpictus and Anopheles...

  14. Temperature effects on the immature development time of Culex eduardoi Casal and Garcia (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Loetti, V.; Schweigmann, N.J.; Burroni, N.E., E-mail: nburroni@ege.fcen.uba.a [Universidad de Buenos Aires (Argentina). Facultad de Ciencias Exactas y Naturales. Grupo de Estudio de Mosquitos

    2011-01-15

    The effect of constant temperatures on the development time from first instar to adult emergence was studied in Culex eduardoi Casal and Garcia reared at 7, 10, 15, 20, 25, 30 or 33 deg C. Data were adjusted to the linear degree-day model and the nonlinear Briere model. According to the linear model, the development time was inversely related to the rearing temperatures between 7 deg C and 25 deg C. Maximum mortality (100%) was recorded at temperatures > 30 deg C. According to the linear model, the development threshold temperature and thermal constant were 5.7 deg C and 188.8 degree days, respectively. The lower and upper threshold temperatures and the optimum temperature for the nonlinear model were -2.3, 30.0 and 28.1 deg C, respectively. (author)

  15. Sentinel site-enhanced near-real time surveillance documenting West Nile virus circulation in two Culex mosquito species indicating different transmission characteristics, Djibouti City, Djibouti.

    Science.gov (United States)

    Faulde, Michael K; Spiesberger, Michael; Abbas, Babiker

    2012-08-01

    The Horn of Africa represents a region formerly known to be highly susceptible to mosquito-borne infectious diseases. In order to investigate whether autochthonous WNV transmission occurs in the Djibouti City area, in how far, and which of, the endemic Culex mosquito species are involved in WNV circulation activity,and whether sentinel site-enhanced near-real time surveillance (SSE-NRTS) may increase WNV detection sensitivity, mosquito vector monitoring was conducted from January 2010 to June 2012. Six monitoring locations, including two identified sentinel sites, considered most probable for potential anthroponotic and zoonotic virus circulation activity, have been continuously employed. Among the 20431 mosquitoes collected, 19069 (93.4%) were Cx. quinquefasciatus, and 1345 (6.6%) Cx. pipiens ssp. torridus. WNV lineage 2 circulation activity was detected between December 20th, 2010 and January 7th, 2011. Overall, 19 WNV RNA-positive mosquito pools were detected. Generally, urban environment-specific WNV-RNA circulation took place in Cx. pipiens ssp. torridus, whereas periurban and rural area-linked circulation was detected only in Cx. quinquefasciatus. Serological investigation data from 10 volunteers employed at the dislocated zoonotic WNV transmission sentinel site suggest that six persons (60%) had an acute, or recent, WNV infection. Results show that WNV should be considered endemic for Djibouti and sentinel site-enhanced near-real time surveillance is an elegant and highly effective epidemiological tool. In Djibouti, the endemicity level, public health impact and transmission modes of vector-borne diseases in concordance with locally optimized monitoring and control regimen deserve further investigation.

  16. EST Table: FS758989 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS758989 E_FL_fcaL_09P10_F_0 10/09/28 34 %/195 aa ref|XP_001842174.1| sensitized chromosome inheritance... modifier 19 [Culex quinquefasciatus] gb|EDS39679.1| sensitized chromosome inheritance m

  17. EST Table: FS758854 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available FS758854 E_FL_fcaL_09I20_F_0 10/09/28 35 %/195 aa ref|XP_001842174.1| sensitized chromosome inheritance... modifier 19 [Culex quinquefasciatus] gb|EDS39679.1| sensitized chromosome inheritance m

  18. Host-feeding patterns of Culex pipiens and other potential mosquito vectors (Diptera: Culicidae) of West Nile virus (Flaviviridae) collected in Portugal.

    Science.gov (United States)

    Osório, Hugo Costa; Zé-Zé, Líbia; Alves, Maria João

    2012-05-01

    The host blood-feeding patterns of mosquito vectors affects the likelihood of human exposure to zoonotic pathogens, including West Nile Virus (family Flaviviridae, genus Flavivirus, WNV). In Portugal, data are unavailable regarding the blood-feeding habits of common mosquito species, including Culex pipiens L., considered the primary vector of WNV to humans. The sources of bloodmeals in 203 blood-fed mosquitoes of nine species collected from June 2007 to November 2010 in 34 Portuguese counties were analyzed by sequencing cytochrome-b partial fragments. Cx. pipiens was the most common species collected and successfully analyzed (n = 135/78). In addition, blood-fed females of the following species were analyzed: Ochlerotatus caspius Pallas (n = 20), Culex theileri Theobald (n = 16), Anopheles maculipennis s.l. Meigen (n = 10), Culiseta longiareolata Macquart (n = 7), Aedes aegypti L. (n = 6), Culex perexiguus Theobald (n = 3), Culiseta annulata Schrank (n = 3), and Ochlerotatus detritus Haliday (n = 3). The Cx. pipiens mosquitoes fed predominantly on birds (n = 55/78, 70.5%), with a high diversity of avian species used as hosts, although human blood was identified in 18 specimens (18/78, 23.1%). No significant differences were found between the host-feeding patterns of blood-fed Cx. pipiens collected in residential and nonresidential habitats. The occurrence of human derived blood meals and the presence of a mix avian-human bloodmeal accordingly suggest this species as a potential vector of WNV. Therefore, in Portugal, Cx. pipiens may play a role both in the avian-to-avian enzootic WNV cycle and in the avian-to-mammal transmission. In this context, the identity of Cx. pipiens (considering the forms molestus and pipiens) and the potential consequence on feeding behavior and WNV transmission are discussed.

  19. Ecological study of avian malaria vectors on the island of Minami-Daito, Japan.

    Science.gov (United States)

    Tsuda, Yoshio; Matsui, Shin; Saito, Atsushi; Akatani, Kana; Sato, Yukita; Takagi, Masaoki; Murata, Koichi

    2009-09-01

    The seasonal prevalence and spatial distribution of mosquitoes were examined as part of an avian malaria study on the oceanic island of Minami-Daito Island, Japan. Because dry ice was not available in this study, yeast-generated CO2 was used to attract biting mosquitoes. Adult mosquitoes were collected biweekly using battery-operated traps enhanced with yeast-generated CO2 and a gravid trap from March 2006 to February 2007. The CO2-baited traps were distributed in 4 different habitats: sugar cane field, forest and vegetation ring, residential area, and swamp area. At 3 collection sites beside sugar cane fields, traps were fixed at 2 different heights (3 and 6 m above the ground). A total of 1,437 mosquitoes of the following 9 species were collected: Culex quinquefasciatus, Aedes albopictus, Coquillettidia sp., Mansonia uniformis, Culex rubithoracis, Armigeres subalbatus, Lutzia fuscanus, Aedes daitensis, and Aedes togoi. Among them, Cx. quinquefasciatus, Ae. albopictus, and Coquillettidia sp. were dominant. The high density and wide distribution of Cx. quinquefasciatus throughout the island suggested the importance of this species as a principal vector of avian malaria on the island.

  20. Modelling Lymphatic Filariasis: Transmission and Control

    NARCIS (Netherlands)

    S. Swaminathan

    2004-01-01

    textabstractLymphatic filariasis (LF) is a mosquito borne parasitic disease of the tropics. Of the three species of parasites causing the disease, W. bancrofti transmitted by Culex quinquefasciatus is the most widely prevalent. Infection can lead to disabling chronic manifestations: lymphoedema,

  1. Expectoration of Flaviviruses during sugar feeding by mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    van den Hurk, Andrew F; Johnson, Petrina H; Hall-Mendelin, Sonja; Northill, Judy A; Simmons, Russell J; Jansen, Cassie C; Frances, Stephen P; Smith, Greg A; Ritchie, Scott A

    2007-09-01

    Biological transmission of arboviruses to a vertebrate host occurs when virions are expelled along with saliva during blood feeding by a hematophagous arthropod. We undertook experiments to determine whether mosquitoes expectorate flaviviruses in their saliva while sugar feeding. Batches of Culex annulirostris Skuse and Culex gelidus Theobald (Diptera: Culicidae) were orally infected with Japanese encephalitis (family Flaviviridae, genus Flavivirus, JEV), Kunjin (family Flaviviridae, genus Flavivirus, KUNV; a subtype of West Nile virus), and Murray Valley encephalitis (family Flaviviridae, genus Flavivirus, MVEV) viruses. After a 7-d extrinsic incubation, these mosquitoes were offered sucrose meals via cotton pledgets, which were removed daily and processed for viral RNA by using real-time TaqMan reverse transcriptase-polymerase chain reaction (RT-PCR) assays. JEV, MVEV, and KUNV RNA was detected in all pledgets removed from batches of Cx. gelidus on days 7-14 postexposure. In contrast, detection rates were variable for Cx. annulirostris, with KUNV detected in 0.3 M sucrose pledgets on all days postexposure, and JEV and MVEV detected on 57 and 50% of days postexposure, respectively. Higher concentrations of sucrose in the pledget did not increase virus detection rates. When individual JEV-infected Cx. gelidus were exposed to the sucrose pledget, 73% of mosquitoes expectorated virus with titers that were detectable by TaqMan RT-PCR. These results clearly show that flaviviruses are expectorated by infected mosquitoes during the process of sugar feeding on artificial pledgets. Potential applications of the method for arboviral bioassays and field surveillance are discussed.

  2. The Role of Culex pipiens L. (Diptera: Culicidae in Virus Transmission in Europe

    Directory of Open Access Journals (Sweden)

    Victor A. Brugman

    2018-02-01

    Full Text Available Over the past three decades, a range of mosquito-borne viruses that threaten public and veterinary health have emerged or re-emerged in Europe. Mosquito surveillance activities have highlighted the Culex pipiens species complex as being critical for the maintenance of a number of these viruses. This species complex contains morphologically similar forms that exhibit variation in phenotypes that can influence the probability of virus transmission. Critical amongst these is the choice of host on which to feed, with different forms showing different feeding preferences. This influences the ability of the mosquito to vector viruses and facilitate transmission of viruses to humans and domestic animals. Biases towards blood-feeding on avian or mammalian hosts have been demonstrated for different Cx. pipiens ecoforms and emerging evidence of hybrid populations across Europe adds another level of complexity to virus transmission. A range of molecular methods based on DNA have been developed to enable discrimination between morphologically indistinguishable forms, although this remains an active area of research. This review provides a comprehensive overview of developments in the understanding of the ecology, behaviour and genetics of Cx. pipiens in Europe, and how this influences arbovirus transmission.

  3. The Role of Culex pipiens L. (Diptera: Culicidae) in Virus Transmission in Europe

    Science.gov (United States)

    Hernández-Triana, Luis M.; Medlock, Jolyon M.; Fooks, Anthony R.; Carpenter, Simon; Johnson, Nicholas

    2018-01-01

    Over the past three decades, a range of mosquito-borne viruses that threaten public and veterinary health have emerged or re-emerged in Europe. Mosquito surveillance activities have highlighted the Culex pipiens species complex as being critical for the maintenance of a number of these viruses. This species complex contains morphologically similar forms that exhibit variation in phenotypes that can influence the probability of virus transmission. Critical amongst these is the choice of host on which to feed, with different forms showing different feeding preferences. This influences the ability of the mosquito to vector viruses and facilitate transmission of viruses to humans and domestic animals. Biases towards blood-feeding on avian or mammalian hosts have been demonstrated for different Cx. pipiens ecoforms and emerging evidence of hybrid populations across Europe adds another level of complexity to virus transmission. A range of molecular methods based on DNA have been developed to enable discrimination between morphologically indistinguishable forms, although this remains an active area of research. This review provides a comprehensive overview of developments in the understanding of the ecology, behaviour and genetics of Cx. pipiens in Europe, and how this influences arbovirus transmission. PMID:29473903

  4. Eficiência e Persistência de Três Produtos Comerciais à Base de Bacillus thuringiensis israelensis e Bacillus sphaericus no controle de Culicidae (Diptera em Lagoas de Tratamento de Efluentes

    Directory of Open Access Journals (Sweden)

    Jose Lopes

    2010-11-01

    Abstract. The hematofagic effect caused by females belonging to some species of Culicidae on humans and animals can be directly related to pathogen transmission, allergic reactions and uneasiness. The emergence of populations resistant to chemical insecticides has fostered the use of alternative methods, mainly biological control. The trials were conducted in three effluent treatment lagoons, on larvae of Culicidae to test the efficiency and persistence of commercial products whose active principles are based on Bacillus thuringiensis israelensis Berliner and Bacillus sphaericus Neide. The products tested were Vectolex (a granulated formulation of B. sphaericus, Sphaericus (a liquid formulation of B. sphaericus and Bt-horus (a liquid formulation of B. thuringiensis. The products were applied biweekly and evaluations were conducted 0, 24, 48, 72, and 120 hours after each application. The lagoons were colonized by Culex nigripalpus Theobald (1.5%, Culex saltanensis Dyar (2.25%, and Culex quinquefasciatus Say (96.25%. Bt-horus reduced larvae by 89.06%, 83.97% and 89.96% at 24, 48 and 72 hours after product application, respectively. The granulated and the liquid formulations containing B. sphaericus reduced larvae by 98.89 % and 98.34% 24 hours after application, and by 99.79% and 99.78% after 48 hours, respectively. The products and the different formulations were effective in controlling larvae of all three Culicidae species in lagoons with high levels of organic matter, but the persistence was recorded in two and three days for products containing respectively B. sphaericus and B. thuringiensis israelensis.

  5. Larvicidal activity of extracts from Ammi visnaga Linn. (Apiaceae) seeds against Culex quinquefasciatus Say. (Diptera: Culicidae)

    Czech Academy of Sciences Publication Activity Database

    Pavela, R.; Vrchotová, Naděžda; Tříska, Jan

    2016-01-01

    Roč. 165, mar (2016), s. 51-57 ISSN 0014-4894 R&D Projects: GA MŠk(CZ) ED1.1.00/02.0073 Institutional support: RVO:67179843 Keywords : botanical larvicide * Furanochromenes * Visnagin * Khellin * Sublethal effect * Mosquito Subject RIV: GC - Agronomy Impact factor: 1.724, year: 2016

  6. EST Table: FS911502 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available eritance modifier 19 [Culex quinquefasciatus] gb|EDS39679.1| sensitized chromosome inheritance...FS911502 E_FL_fufe_23G14_F_0 11/12/09 n.h 10/09/28 35 %/234 aa ref|XP_001842174.1| sensitized chromosome inh

  7. Directory of Open Access Journals (Sweden)

    Gonzalo Batallán

    2013-01-01

    Full Text Available INTRODUCTION: The aim of the present study was to analyze the larvicidal activity of different crude extracts of Larrea cuneifolia and its most abundant lignan, nordihydroguaiaretic acid (NDGA, against Culex quinquefasciatus. METHODS: Chloroform, methanol, and aqueous extracts from L. cuneifolia and NDGA were tested against larvae of Cx. quinquefasciatus under laboratory conditions. RESULTS: The chloroform extract showed the highest larvicidal effect, with an estimated LC50 of 0.062 mg/ml. NDGA also demonstrated significant larvicidal activity with an estimated LC50 of 0.092 mg/ml. CONCLUSIONS: These results indicate that the chloroform extract of L. cuneifolia and NDGA are promising insecticides of botanical origin that could be useful for controlling Cx. quinquefasciatus.

  8. Bancroftian filariasis in Belém, Pará State: possibilities for eradication by introducing modern methods of control for Culex quinquefasciatus A filariose bancroftiana em Belém, Pará: possibilidades atuais de erradicação mediante a integração à campanha de novos métodos de controle da população de Culex quinquefasciatus

    Directory of Open Access Journals (Sweden)

    Habib Fraiha Neto

    1993-12-01

    Full Text Available For the past four decades, Belém has been considered to be the largest focus of Bancroftian filariasis in the Amazon region and one of the most important ones in Brazil. In 1952, practically one-fifth of the population was infected and it was estimated that there were 2,500 cases of Bancroftian elephantiasis. The major factor considered to be responsible for this situation was the high density of the main vector species: it was calculated that in April 1943 there was a mean of 67 infected mosquitoes per house. A control campaign was initiated in 1952, involving treatment of patients with diethylcarbamazine, as well as control of the vector. In 1956, vector control was discontinued because of a lack of efficient insecticides and financial limitations. Even so, the campaign was very successful and the incidence was reduced from 19.9% to 0.03%. Total eradication could be achieved if new methods of vector control were introduced, such as the use of Reiter's expanded polystyrene balls in cesspits and pit latrines, biological control using pathogenic bacteria, and improvement of basic sanitation.Há mais de quatro décadas Belém é considerada o maior foco de bancroftose da região amazônica e um dos mais importantes do Brasil. Em 1952, praticamente um quinto de sua população apresentava microfilárias no sangue, estimando-se em 2.500 os casos de elefantíase. O fator considerado o maior condicionante de tão extraordinária freqüência era a alta densidade local do principal vetor, Culex quinquefasciatus. Em abril de 1943 calculava-se uma média de 67 fêmeas da espécie infectadas por domicílio. Uma campanha de controle foi deflagrada em 1952, incluindo busca ativa e tratamento dos casos com dietilcarbamazina, além medidas de combate ao vetor. Estas foram abandonadas em 1956, por força da ineficácia ou do alto custo dos inseticidas. Ainda assim, a campanha foi muito bem sucedida, reduzindo a incidência de 19,9 para 0,03%. Hoje, a erradica

  9. Larvicidal, pupicidal and insecticidal activities of Cosmos bipinnatus ...

    African Journals Online (AJOL)

    Purpose: To evaluate the larvicidal, pupicidal and insecticidal activities of Cosmos bipinnatus, Foenuculum vulgare and Tagetes minuta leaf extracts against Culex quinquefasciatus mosquitoes. Methods: The leaves of the plants were extracted with distilled water, ethanol (95 %), and hexane and the extracts screened for ...

  10. Mosquitocidal and water purification properties of Cynodon dactylon, Aloe vera, Hemidesmus indicus and Coleus amboinicus leaf extracts.

    Science.gov (United States)

    Ethanolic extracts of Cynodon dactylon, Aloe vera, Hemidesmus indicus and Coleus amboinicus were tested for toxicity to 3rd instar Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. Median lethal concentrations (LC50) were, respectively, 0.44%, 0.51%, 0.59% and 0.68%. Cynodon dactylon...

  11. High Insecticides Resistance in Culex pipiens (Diptera: Culicidae from Tehran, Capital of Iran

    Directory of Open Access Journals (Sweden)

    Yaser Salim-Abadi

    2016-10-01

    Full Text Available Background: During recent years transmission of Dirofilaria immitis (dog heart worm by Culex pipiens and West Nile virus have been reported from Iran. The present study was preformed for evaluating the susceptibility status of Cx. pipiens collected from capital city of Tehran, Iran.Methods: Four Insecticides including: DDT 4%, Lambdacyhalothrin 0.05%, Deltamethrin 0.05% and Cyfluthrin 0.15 % according to WHO standard  methods were used for evaluating the susceptibility status of Cx. pipiens from Tehran moreover  For comparison susceptibility status a Laboratory strain also was used.  Bioassay data were ana­lyzed using Probit program. The lethal time for 50% and 90% mortality (LT50 and LT90 values were calculated from regression line.Results: The susceptibility status of lab strain of Cx. pipiens revealed that it is susceptible to Lambdacyhalothrin, Deltamethrin, Cyfluthrin and resistant to DDT. Moreover cyfluthrin with LT50=36 seconds and DDT with LT50=3005 seconds had the least and most LT50s. Field population was resistance to all tested insecticides and DDT yielded no mortality.Conclusion: Highly resistance level against all WHO recommended imagicides were detected in field populations. We suggest more biochemical and molecular investigations to detect resistance mechanisms in the field population for further decision of vector control.

  12. Attractive toxic sugar baits: Control of mosquitoes with the low risk active ingredient dinotefuran and potential impacts on non-target organisms in Morocco

    Science.gov (United States)

    We evaluated the efficacy of ATSB in the laboratory and the field with the low risk active ingredient dinotefuran against mosquito populations. Assays indicated that dinotefuran in solution with the sugar baits was ingested and resulted in high mortality of female Culex quinquefasciatus and Aedes a...

  13. Native Argentinean cyclopoids (Crustacea: Copepoda as predators of Aedes aegypti and Culex pipiens (Diptera: Culicidae mosquitoes

    Directory of Open Access Journals (Sweden)

    María C Tranchida

    2009-12-01

    Full Text Available Copepods from La Plata, Argentina were investigated to characterize the local community of larvivorous copepods inhabiting mosquito breeding sites and to identify new predator species of the mosquitoes which occur in artificial containers, Aedes aegypti and Culex pipiens. Diversity of larvivorous cyclopoids was highest in permanent pools. Predation by sex and age, selectivity on mosquito species, and daily predation rate during five days were studied for Acanthocyclops robustus, Diacyclops uruguayensis, Macrocyclops albidus and Mesocyclops longisetus. Female copepods presented the highest predatory capacity. No predatory preference for mosquito species was found. According to overall predation potential, copepods were ranked as follows: D. uruguayensis Se hizo una prospección de copépodos en La Plata, Argentina, con los objetivos de caracterizar la comunidad local de copépodos larvívoros en sitios de cría de mosquitos, e identificar nuevas especies depredadoras de los mosquitos de contenedores artificiales Aedes aegypti y Culex pipiens. La diversidad de ciclopoides larvívoros fue máxima en charcos permanentes. Se examinó la depredación por sexos y edad, la selectividad por especies de mosquito, y la tasa de depredación diaria durante cinco días en Acanthocyclops robustus, Diacyclops uruguayensis, Macrocyclops albidus y Mesocyclops longisetus. Los copépodos hembra presentaron la capacidad depredadora más alta. No se encontró preferencia por alguna especie de mosquito. De acuerdo al potencial de depredación en general, los copépodos se ordenan así: D. uruguayensis < A. robustus < M. albidus < M. longisetus. También se evaluó la tolerancia a la desecación del hábitat y la capacidad de resistir en agua de contenedores artificiales. D. uruguayensis y A. robustus sobrevivieron en condiciones de sequía, pero D. uruguayensis presentó menor supervivencia en agua de floreros de cementerio. M. albidus no sobrevivió condiciones de

  14. Host selection patterns of Culex tarsalis (Diptera: Culicidae) at wetlands near the Salton Sea, Coachella Valley, California, 1998-2002.

    Science.gov (United States)

    Reisen, William K; Lothrop, Hugh D; Thiemann, Tara

    2013-09-01

    The bloodmeal hosts used by Culex tarsalis Coquillett collected along the Salton Sea in Coachella Valley, CA, during 1998-2002 were identified using sequences of the cytochrome c oxidase I gene identified from Barcode of Life database. Overall, 265 (83.3%) of 318 bloodmeals were identified, of which 76.6% fed on birds, 18.1% on mammals, and 5.3% on reptiles. Forty-seven different hosts were identified, none of which comprised > 12.5% of the total. Although Cx. tarsalis exhibits specific host-seeking flight patterns, bloodmeals seemed to be acquired opportunistically, thereby limiting potential arbovirus transmission efficiency in species-rich environments.

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

    Science.gov (United States)

    2011-06-01

    Lee, and A.H. Azahari. 2005. Adult and larval insecticide susceptibility status of Culex quinquefasciatus (Say) mosquitoes in Kuala Lumpur Malaysia ...Trop. Biomed. 22: 63-68. Nayar, J.K. and D.M. Sauerman, Jr. 1971. The effects of diet on life-span, fecundity and flight potential of Aedes

  16. Functional characterization of the dual allatostatin-A receptors in mosquitoes

    DEFF Research Database (Denmark)

    Christ, Peter; Hill, Sharon R.; Schachtner, Joachim

    2018-01-01

    , there are two copies of AstAR, contrasting with the single copy found in other insects. In this study, we identified and cloned the dual AstAR system of two important disease vectors Aedes aegypti and Culex quinquefasciatus, and compared them with those previously described, including those in Anopheles...

  17. Estudio ambiental de criaderos de anopheles (n albimanus (diptera: culicidae en la provincia holguín. año 2009

    Directory of Open Access Journals (Sweden)

    Niurka Lien Torres-Rodríguez

    2012-01-01

    Full Text Available Se presenta el estudio de la incidencia y comportamiento del anopheles albimanus, (transmisor del paludismo o malaria en los 282 criaderos potenciales y habituales de culícidos de la provincia holguín durante el año 2009.a partir de la información semanal enviada a la unidad provincial de vigilancia y lucha antivectorial (upvla, se caracterizó el comportamiento de esta especie la que se encuentra ampliamente distribuida en la provincia. Se observó mayor incidencia en los municipios FranK País, Rafael Freyre y Mayarí, con predominio en zanjas, lagunas y arroyos. Se aprecia una mayor asociación con el culex quinquefasciatus y el mayor número de muestras larvarias fueron colectadas en octubre. Teniendo en cuenta los resultados obtenidos y el riesgo de introducción de esta enfermedad en el país se recomienda continuar los estudios de esta especie en la provincia.

  18. Determination of Mosquitoes Fauna (Culicidae: Diptera in Poldokhtar County of Lorestan Province, 2015

    Directory of Open Access Journals (Sweden)

    Zahirnia A H

    2017-09-01

    Full Text Available Introduction: Insects as the largest category of arthropods include numerous groups and families that the most important of them belong to order Diptera, family Culicidae. Because of feeding on the human's blood, a number of species of this family have been known as responsible for the transmission of pathogens for many diseases such as malaria, filariasis, encephalitis, yellow fever and dengue fever in the world. Given that no research has been conducted to determine the fauna of existing mosquitoes in the city of Poldokhtar, Lorestan Province, the present study aimed to exactly determine the mosquitoes' fauna in this city to perform appropriate prevention measures. Methods: In this faunistic and cross-sectional descriptive study, four urban areas and four rural areas in four geographic directions in the city of Poldokhtar were determined. In each urban area, two places and in each designated rural area, four places including two human places and two animal places were selected. From the early of April 2015 to the early of January 2016, larvae, pupae and adult mosquitoes of the Culicidae family were collected. Sampling methods for larvae, pupae and mature were ladling, night catch, total and hand catch with an aspirator. Characteristics including the name of the collector, date of collection, code related to habitat, habitat status (permanent or temporary, type of vegetation cover, type of substrate, and the situation of sunlight were recorded in the related form. The samples were identified by resources and valid identification keys. The data were analyzed using the SPSS software version 19. Results: Totally, 5392 mosquito adults of the Culicidae family including 1818 mosquito adults and 3574 larvae in designated areas in the city as well as four rural areas were collected. The three genera Anopheles (21.9%, Culex (64.6%, and Culiseta (13.5% were diagnosed. Also, from three genera, 12 species were identified as follows: Culex theiler, Cx

  19. Microsporidia parásitos de larvas de mosquito de la Costa Pacífica del Chocó

    Directory of Open Access Journals (Sweden)

    Zuluaga Juan S.

    1993-12-01

    Full Text Available Two genera of Microsporidia were found infecting mosquito larvae in three localities on the Pacific coast of Choco. Vavraia sp. (Microsporida: Pleistophoridae was found in larvae of Wyeomyia circumcincta, W. simmsi and Anopheles albimanus collected from plants of the Bromeliacea family in Arusí y Joví. Amblyospora sp. (Microsporida: Amblyosporidae was found parasitizingAedes angustivittatuslarvae COllectedfrom a terrestrial breeding pond in the locality of Nuqur. Morphology of the spores of the two parasites under light microscopy is described, as well as preliminary data on host range when exposed to laboratory rearad Aedes aegypti, Culex quinquefasciatus and Anopheles albimanus. Their rola in mosquito control is discussed.Se reportan dos géneros de microsporidia que parasitan larvas de mosquitos en criaderos naturales de tres localidades en la costa Pacffica Chocoana. Vavraia sp. (Microsporida: Pleistophoridae parásita larvas de Wyeomyia circumcincta, de Wyeomya simmsi y de Anopheles neivai, recolectadas en las rosetas de especies de la familia Bromeliaceae en las localidades de Arusí y Joví. Amblyospora sp. (Microsporida: Amblyosporidae parásita larvas deAedes angustivittatusde criaderos terrestres semipermanentes en la localidad de Nuquí. Se describe la morfología de estos dos microsporidia al microscopio óptico. Estudios preliminares de infección en larvas de Aedes aegypti, Culex quinquefasciatus yAnopheles albimanus, criadas en laboratorio, indican que Vavraia sp. infecta las tres especies, con preferencia a Culex quinquefasciatus. Las larvas expuestas a esporas de Amblyospora sp. no presentaron infección. Se discute el posible papel de estos dos géneros en el control de las poblaciones de mosquitos.

  20. Relative performance of indoor vector control interventions in the Ifakara and the West African experimental huts.

    Science.gov (United States)

    Oumbouke, Welbeck A; Fongnikin, Augustin; Soukou, Koffi B; Moore, Sarah J; N'Guessan, Raphael

    2017-09-19

    West African and Ifakara experimental huts are used to evaluate indoor mosquito control interventions, including spatial repellents and insecticides. The two hut types differ in size and design, so a side-by-side comparison was performed to investigate the performance of indoor interventions in the two hut designs using standard entomological outcomes: relative indoor mosquito density (deterrence), exophily (induced exit), blood-feeding and mortality of mosquitoes. Metofluthrin mosquito coils (0.00625% and 0.0097%) and Olyset® Net vs control nets (untreated, deliberately holed net) were evaluated against pyrethroid-resistant Culex quinquefasciatus in Benin. Four experimental huts were used: two West African hut designs and two Ifakara hut designs. Treatments were rotated among the huts every four nights until each treatment was tested in each hut 52 times. Volunteers rotated between huts nightly. The Ifakara huts caught a median of 37 Culex quinquefasciatus/ night, while the West African huts captured a median of 8/ night (rate ratio 3.37, 95% CI: 2.30-4.94, P  4-fold higher mosquito exit relative to the West African huts (odds ratio 4.18, 95% CI: 3.18-5.51, P < 0.0001), regardless of treatment. While blood-feeding rates were significantly higher in the West African huts, mortality appeared significantly lower for all treatments. The Ifakara hut captured more Cx. quinquefasciatus that could more easily exit into windows and eave traps after failing to blood-feed, compared to the West African hut. The higher mortality rates recorded in the Ifakara huts could be attributable to the greater proportions of Culex mosquitoes exiting and probably dying from starvation, relative to the situation in the West African huts.

  1. West Nile virus ecology in a tropical ecosystem in Guatemala.

    Science.gov (United States)

    Morales-Betoulle, Maria E; Komar, Nicholas; Panella, Nicholas A; Alvarez, Danilo; López, María R; Betoulle, Jean-Luc; Sosa, Silvia M; Müller, María L; Kilpatrick, A Marm; Lanciotti, Robert S; Johnson, Barbara W; Powers, Ann M; Cordón-Rosales, Celia

    2013-01-01

    West Nile virus ecology has yet to be rigorously investigated in the Caribbean Basin. We identified a transmission focus in Puerto Barrios, Guatemala, and established systematic monitoring of avian abundance and infection, seroconversions in domestic poultry, and viral infections in mosquitoes. West Nile virus transmission was detected annually between May and October from 2005 to 2008. High temperature and low rainfall enhanced the probability of chicken seroconversions, which occurred in both urban and rural sites. West Nile virus was isolated from Culex quinquefasciatus and to a lesser extent, from Culex mollis/Culex inflictus, but not from the most abundant Culex mosquito, Culex nigripalpus. A calculation that combined avian abundance, seroprevalence, and vertebrate reservoir competence suggested that great-tailed grackle (Quiscalus mexicanus) is the major amplifying host in this ecosystem. West Nile virus transmission reached moderate levels in sentinel chickens during 2007, but less than that observed during outbreaks of human disease attributed to West Nile virus in the United States.

  2. Genetic variation associated with mammalian feeding in Culex pipiens from a West Nile virus epidemic region in Chicago, Illinois.

    Science.gov (United States)

    Huang, Shaoming; Hamer, Gabriel L; Molaei, Goudarz; Walker, Edward D; Goldberg, Tony L; Kitron, Uriel D; Andreadis, Theodore G

    2009-12-01

    Mosquitoes of the Culex pipiens complex are important vectors of West Nile virus in the United States. We examined the genetic variations of Cx. pipiens mosquitoes from Chicago, Illinois that were determined to be principally ornithophilic but exhibited a relatively higher inclination for mammalian hosts including humans. Microsatellite analysis of 10 polymorphic markers was performed on 346 engorged Cx. pipiens specimens with identified avian or mammalian blood meals. Our results indicated that there were no significant differences in allelic richness, the pattern of conformity to Hardy-Weinberg equilibrium, and linkage disequilibrium, nor was there overall genetic differentiation between specimens with avian- and mammalian-derived blood meals. However, Cx. pipiens form pipiens with mammalian- (including human-) derived blood meals had significantly higher ancestry (p 0.05) and the proportion of hybrids (p > 0.05) from Cx. quinquefasciatus (population from Harris Country, Texas). No temporal genetic variation was detected in accordance with the observation that there was no shift in blood feeding from birds to mammals. The results of this study in conjunction with regional host-feeding behavior suggest that the probability of genetic ancestry from Cx. pipiens f. molestus may predispose mosquitoes to feed more readily on mammals; however, the genetic mechanisms are unknown.

  3. Evaluation of the Larvicidal Activities of Bacillus Sphaericus on ...

    African Journals Online (AJOL)

    Studies on the larvicidal activities of Bacillus sphaericus, against Culex quinquefasciatus mosquitoes found in this area (Sokoto), was carried out. The B. sphaericus (SPH 88) was obtained from Paseur Institute in Paris (France) in the form of a water dispersible powder. About 50mg of the powder was dissolved in 10ml ...

  4. Culex annulirostris (Diptera: Culicidae) host feeding patterns and Japanese encephalitis virus ecology in northern Australia.

    Science.gov (United States)

    Hall-Mendelin, Sonja; Jansen, Cassie C; Cheah, Wai Yuen; Montgomery, Brian L; Hall, Roy A; Ritchie, Scott A; Van den Hurk, Andrew F

    2012-03-01

    Japanese encephalitis virus (JEV) transmission in northern Australia has, in the past, been facilitated by Culex annulirostris Skuse feeding on domestic pigs, the primary amplifying hosts of the virus. To further characterize mosquito feeding behavior in northern Australia, 1,128 bloodmeals from Cx. annulirostris were analyzed using a double-antibody enzyme-linked immunosorbent assay. Overall, Cx. annulirostris obtained > 94% of blood meals from mammals, comprising marsupials (37%), pigs (20%), dogs (16%), and cows (11%), although the proportion feeding on each of these host types varied between study locations. Where JEV activity was detected, feeding rates on pigs were relatively high. At the location that yielded the first Australian mainland isolate of JEV from mosquitoes, feral pigs (in the absence of domestic pigs) accounted for 82% of bloodmeals identified, representing the first occasion that feeding on feral pigs has been associated with JEV transmission in Australia. Interestingly, blood meals identified, or infected mosquitoes immigrating from areas where domestic pigs are housed, may have contributed to transmission at this location. Because Cx. annulirostris is both an opportunistic feeder and the primary JEV vector in the region, environmental characteristics and host presence can determine JEV transmission dynamics in northern Australia.

  5. Field evaluation of effectiveness of the BG-Sentinel, a new trap for capturing adult Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Rafael Maciel-de-Freitas

    2006-05-01

    Full Text Available In recent years, the development of new tools to gather field information about vector ecological parameters has increased. This report evaluated the BG-Sentinel Trap (BGS-Trap, a promising new attempt to improve collection of the dengue vector, Aedes aegypti. The efficacy of the BGS-Trap was compared with the CDC backpack aspirator, one of the commonest used methods for capturing adult mosquitoes. BGS-Traps captured significantly more Ae. aegypti males (chi2 = 21.774, df = 1, P < 0.05 and females (chi2 = 56.007, df = 1, P < 0.05 than CDC aspirator during all days of field collection. However, CDC aspirator was significantly more efficient to capture Culex quinquefasciatus males (chi2 = 5.681, df = 1, P < 0.05 and females (chi2 = 6.553, df = 1, P < 0.05. BGS-Traps captured host-seeking females (varying between 68.75 to 89.8% in detriment of females in other behavioral and physiological stages. BGS-Traps proved to be efficient and can be used for monitoring adult mosquito populations.

  6. Ecological characterization and molecular differentiation of Culex pipiens complex taxa and Culex torrentium in eastern Austria.

    Science.gov (United States)

    Zittra, Carina; Flechl, Eva; Kothmayer, Michael; Vitecek, Simon; Rossiter, Heidemarie; Zechmeister, Thomas; Fuehrer, Hans-Peter

    2016-04-11

    Culex pipiens complex taxa differ in behaviour, ecophysiology and epidemiologic importance. Despite their epidemiologic significance, information on genetic diversity, occurrence and seasonal and spatial distribution patterns of the Cx. pipiens complex is still insufficient. Assessment of seasonal and spatial distribution patterns of Culex pipiens forms and their congener Cx. torrentium is crucial for the understanding of their vector-pathogen dynamics. Female mosquitoes were trapped from April-October 2014 twice a month for a 24-h time period with BG-sentinel traps at 24 sampling sites in eastern Austria, using carbon dioxide as attractant. Ecological forms of Cx. pipiens s.l. and their hybrids were differentiated using the CQ11 locus, and Cx. pipiens forms and their congener Cx. torrentium using the ACE-2 gene. Differential exploitation of ecological niches by Cx. pipiens forms and Cx. torrentium was analysed using likelihood ratio tests. Possible effects of environmental parameters on these taxa were tested using PERMANOVA based on distance matrices and, if significant, were modelled in nMDS ordination space to estimate non-linear relationships. For this study, 1476 Culex spp. were sampled. Culex pipiens f. pipiens representing 87.33 % of the total catch was most abundant, followed by hybrids of both forms (5.62 %), Cx. torrentium (3.79 %) and Cx. pipiens f. molestus (3.25 %). Differences in proportional abundances were found between land cover classes. Ecological parameters affecting seasonal and spatial distribution of these taxa in eastern Austria are precipitation duration, air temperature, sunlight and the interaction term of precipitation amount and the Danube water level, which can be interpreted as a proxy for breeding habitat availability. The Cx. pipiens complex of eastern Austria comprises both ecologically different forms, the mainly ornithophilic form pipiens and the mainly mammalophilic and anthropophilic form molestus. Heterogeneous agricultural

  7. Field trials with tank mixtures of Bacillus thuringiensis subsp. israelensis and Bacillus sphaericus formulations against Culex pipiens larvae in septic tanks in Antalya, Turkey.

    Science.gov (United States)

    Cetin, Huseyin; Dechant, Peter; Yanikoglu, Atila

    2007-06-01

    Efficacy of tank mixtures of commercial Bacillus thuringiensis subsp. israelensis (Bti) and Bacillus sphaericus (Bs) water-dispersable granule (WDG) formulations was evaluated in septic tanks, against Culex pipiens L. (Diptera: Culicidae) larvae. VectoLex WDG (Bs) + VectoBac WDG (Bti) were evaluated at various ratios from 488 g/ha VectoLex + 250 g/ha VectoBac up to 3,000 g/ha of each. All applications and ratios delivering VectoLex WDG at a rate equal to or greater than 988 g/ha provided more than 90% control for 28 days after treatment. The lowest dose provided this level of control for at least 7 days after treatment, with greater than 80% control after 2 wk. These results suggest that a retreatment interval of 2 wk is recommended with the lowest dose and retreatment intervals of 4 or more wk are recommended with the doses equal to or higher than 988 g/ha VectoLex + 250 g/ha VectoBac.

  8. Morphometric studies on Culex quinquefasciatus and Mansonia ...

    African Journals Online (AJOL)

    are difficult to identify based solely on examination of adult females using the available morphological keys. In this study, adult mosquitoes were collected ... ures) it is necessary to identify the species of adult females which are found near ... M. africana is known to transmit Rift Valley fever. (Meegan & Bailey, 1988; Fontenille ...

  9. Permanent Genetic Resources added to Molecular Ecology Resources Database 1 October 2011 - 30 November 2011

    KAUST Repository

    Abreu, Aluana Gonç alves; Albaina, A.; Alpermann, Tilman J.; Apkenas, Vanessa E.; Bankhead-Dronnet, Sté phanie; Bergek, Sara; Berumen, Michael L.; Cho, Changhung; Clobert, Jean; Coulon, Auré lie; De Feraudy, D.; Estonba, Andone; Hankeln, Thomas M A; Hochkirch, Axel; Hsu, Tsaiwen; Huang, Tsurngjuhn; Irigoien, Xabier; Iriondo, Mikel; Kay, Kathleen M.; Kinitz, Tim; Kothera, Linda; Le Hé nanff, Maxime; Lieutier, Franç ois; Lourdais, Olivier; Macrini, Camila M T; Manzano, Carmen; Martin, Carine; Morris, Veronica Ruth Franco; Nanninga, Gerrit B.; Pardo, D.; Plieske, Jö rg; Pointeau, Sophie; Prestegaard, Tore; Quack, Markus; Richard, Murielle; Savage, Harry M.; Schwarcz, Kaiser D.; Shade, Jessica; Simms, Ellen L.; Solferini, Vera Nisaka; Stevens, Virginie M.; Veith, Michael W.; Wen, Meijuan; Wicker, Florian; Yost, Jenn M.; Zarraonaindia, Iratxe

    2012-01-01

    This article documents the addition of 139 microsatellite marker loci and 90 pairs of single-nucleotide polymorphism sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Aglaoctenus lagotis, Costus pulverulentus, Costus scaber, Culex pipiens, Dascyllus marginatus, Lupinus nanus Benth, Phloeomyzus passerini, Podarcis muralis, Rhododendron rubropilosum Hayata var. taiwanalpinum and Zoarces viviparus. These loci were cross-tested on the following species: Culex quinquefasciatus, Rhododendron pseudochrysanthum Hay. ssp. morii (Hay.) Yamazaki and R. pseudochrysanthum Hayata. This article also documents the addition of 48 sequencing primer pairs and 90 allele-specific primers for Engraulis encrasicolus. © 2012 Blackwell Publishing Ltd.

  10. Permanent Genetic Resources added to Molecular Ecology Resources Database 1 October 2011 - 30 November 2011

    KAUST Repository

    Abreu, Aluana Gonçalves

    2012-02-01

    This article documents the addition of 139 microsatellite marker loci and 90 pairs of single-nucleotide polymorphism sequencing primers to the Molecular Ecology Resources Database. Loci were developed for the following species: Aglaoctenus lagotis, Costus pulverulentus, Costus scaber, Culex pipiens, Dascyllus marginatus, Lupinus nanus Benth, Phloeomyzus passerini, Podarcis muralis, Rhododendron rubropilosum Hayata var. taiwanalpinum and Zoarces viviparus. These loci were cross-tested on the following species: Culex quinquefasciatus, Rhododendron pseudochrysanthum Hay. ssp. morii (Hay.) Yamazaki and R. pseudochrysanthum Hayata. This article also documents the addition of 48 sequencing primer pairs and 90 allele-specific primers for Engraulis encrasicolus. © 2012 Blackwell Publishing Ltd.

  11. Biotin/avidin sandwich enzyme-linked immunosorbent assay for Culicidae mosquito blood meal identification

    Directory of Open Access Journals (Sweden)

    A. M. Marassá

    2008-01-01

    Full Text Available The knowledge of mosquitoes Culicidae host feeding patterns is basic to understand the roles of different species and to indicate their importance in the epidemiology of arthropod-borne diseases. A laboratory assay was developed aiming at standardizing the biotin-avidin sandwich enzyme-linked immunosorbent assay, which was unprecedented for mosquito blood meal identification. The enzyme-linked immunosorbent assay (ELISA activity was evaluated by the detection of titers on each sample of the 28 blood-fed Culex quinquefasciatus. In light of the high sensitivity that the technique permits, by means of small quantities of specific antibodies commercially provided and phosphatase substrate which reinforces additional dilutions, human and rat blood meals were readily identified in all laboratory-raised Culex quinquefasciatus tested. The assay was effective to detect human blood meal dilutions up to 1:4,096, which enables the technique to be applied in field studies. Additionally, the present results indicate a significant difference between the detection patterns recorded from human blood meal which corroborate the results of host feeding patterns.

  12. BIOLARVASIDA EKSTRAK ETANOL KULIT NANAS (Ananas comosus L. Merr TERHADAP LARVA NYAMUK Culex Sp.

    Directory of Open Access Journals (Sweden)

    Siti Juariah

    2017-10-01

    Full Text Available ABSTRAK   Nanas merupakan salah satu komoditi asal Provinsi Riau. Setiap tahun nanas mengalami peningkatan dengan semakin meningkatnya produksi nanas maka limbah yang dihasilkan akan semakin meningkat. Pada limbah kulit nanas diduga terdapat senyawa alkaloid yang dapat membunuh larva nyamuk Culex Sp. Nyamuk yang termasuk dalam genus Culex dikenal sebagai vektor penular arbovirus, demam kaki gajah, dan malaria pada unggas. Pengendalian serangga umumnya dilakukan menggunakan pestisida sintetik. Penggunaan senyawa kimia yang bersifat sintetik sangat berbahaya bagi pengguna yang terpajan. Tujuan dari penelitian ini adalah untuk menentukan efektifitas ekstrak etanol kulit nanas dan mengetahui jumlah larva yang mati dengan menentukan konsentrasi terbaik dari ekstrak etanol kulit nanas (AnanascomosusL. terhadap larva nyamuk culex Sp. Penelitian ini bersifat Eksperimen Laboratory, yaitu meneliti tentang uji mortalitas larva nyamuk Culex Sp setelah pemberian ekstrak etanol kulit nanas (AnanascomosusL.. Hasil penelitian yang didapatkan bahwa ekstrak etanol kulit nanas dapat dibuktikan pada tingkat konsentrasi 1% angka kematian larva nyamuk telah mencapai 72,5%. Sedangkan pada konsentrasi 4% telah mampu membunuh larva sebesar 97,5%. Kata Kunci        : Ekstraketanol, Kulit nanas, Culex Sp.   ABSTRACT                Pineapple is one of the commodities origin of Riau Province. Each year the pineapple increases with the increasing production of pineapple so the waste generated will increase. In pineapple leaf waste is suspected of alkaloid compounds that can kill the mosquito larvae Culex Sp. The mosquitoes belonging to the genus Culex are known as arbovirus-transmitting vectors, elephant leg fever, and malaria in poultry. Insect control is generally done using synthetic pesticides. The use of synthetic chemicals is very dangerous for exposed users. The purpose of this study was to determine the effectiveness of pineapple ethanol

  13. Seasonal abundance and molecular identification of West Nile virus ...

    African Journals Online (AJOL)

    Federal Medical Centre, Microbiology Unit, Pathology Department. 2. University of Ibadan .... grouped and analyzed using statistical software SPSS 12.0. Results. A total of .... culex quinqueasciatus (Diptera: Culicidea) in Mexico city. Parasites ...

  14. AcEST: BP917936 [AcEST

    Lifescience Database Archive (English)

    Full Text Available terized protein (Fragmen... 36 1.0 tr|B0W1A0|B0W1A0_CULQU Shuttle craft OS=Culex quinquefasciatus G... 35 1.... Query: 38 HP 33 HP Sbjct: 161 HP 162 >tr|B0W1A0|B0W1A0_CULQU Shuttle craft OS=Cu

  15. Ecology of potential West Nile virus vectors in southeastern Louisiana: enzootic transmission in the relative absence of Culex quinquefasciatus

    Science.gov (United States)

    Godsey, Marvin S.; King, Raymond J.; Burkhalter, Kristen; Delorey, Mark; Colton, Leah; Charnetzky, Dawn; Sutherland, Genevieve; Ezenwa, Vanessa O.; Wilson, Lawrence A.; Coffey, Michelle; Milheim, Lesley E.; Taylor, Viki G.; Palmisano, Charles; Wesson, Dawn M.; Guptill, Stephen C.

    2013-01-01

    A study of West Nile virus (WNV) ecology was conducted in St. Tammany Parish, Louisiana, from 2002 to 2004. Mosquitoes were collected weekly throughout the year using Centers for Disease Control and Prevention (CDC) light traps placed at 1.5 and 6 m above the ground and gravid traps. A total of 379,466 mosquitoes was collected. WNV was identified in 32 pools of mosquitoes comprising four species; 23 positive pools were from Culex nigripalpus collected during 2003. Significantly more positive pools were obtained from Cx. nigripalpus collected in traps placed at 6 m than 1.5 m that year, but abundance did not differ by trap height. In contrast, Cx. nigripalpus abundance was significantly greater in traps placed at 6 m in 2002 and 2004. Annual temporal variation in Cx. nigripalpus peak seasonal abundance has important implications for WNV transmission in Louisiana. One WNV-positive pool, from Cx. erraticus, was collected during the winter of 2004, showing year-round transmission. The potential roles of additional mosquito species in WNV transmission in southeastern Louisiana are discussed. Disclaimer: The opinions expressed in this article are the opinions of the authors and do not necessarily represent the views of the Centers for Disease Control and Prevention. This article has been peer reviewed and approved for publication consistent with U.S. Geological Survey Fundamental Science Practices (http//pubs.usgs.gov/circ/1367/). Any use of trade, firm, or product names is for descriptive purposes only and does not imply endorsement by the U.S. Government.

  16. Seasonal blood-feeding behavior of Culex tarsalis (Diptera: Culicidae) in Weld County, Colorado, 2007.

    Science.gov (United States)

    Kent, Rebekah; Juliusson, Lara; Weissmann, Michael; Evans, Sara; Komar, Nicholas

    2009-03-01

    Studies on Culex tarsalis Coquillett in Colorado have shown marked seasonal variation in the proportion of blood meals from birds and mammals. However, limitations in the specificity of antibodies used in the precipitin test and lack of vertebrate host availability data warrant revisiting Cx. tarsalis blood feeding behavior in the context of West Nile virus (WNV) transmission. We characterized the host preference of Cx. tarsalis during peak WNV transmission season in eastern Colorado and estimated the relative contribution of different avian species to WNV transmission. Cx. tarsalis preferred birds to mammals each month, although the proportion of blood meals from mammals increased in July and August. The distribution of blood meals differed significantly across months, in part because of changes in the proportion of blood meals from American robins, a preferred host. The estimated proportion of WNV-infectious vectors derived from American robins declined from 60 to 1% between June and August. The majority of avian blood meals came from doves, preferred hosts that contributed 25-40% of the WNV-infectious mosquitoes each month. Active WNV transmission was observed in association with a large house sparrow communal roost. These data show how seasonal patterns in Cx. tarsalis blood feeding behavior relate to WNV transmission in eastern Colorado, with the American robin contributing greatly to early-season virus transmission and a communal roost of sparrows serving as a focus for late-season amplification.

  17. Rift Valley fever virus epidemic in Kenya, 2006/2007: the entomologic investigations.

    Science.gov (United States)

    Sang, Rosemary; Kioko, Elizabeth; Lutomiah, Joel; Warigia, Marion; Ochieng, Caroline; O'Guinn, Monica; Lee, John S; Koka, Hellen; Godsey, Marvin; Hoel, David; Hanafi, Hanafi; Miller, Barry; Schnabel, David; Breiman, Robert F; Richardson, Jason

    2010-08-01

    In December 2006, Rift Valley fever (RVF) was diagnosed in humans in Garissa Hospital, Kenya and an outbreak reported affecting 11 districts. Entomologic surveillance was performed in four districts to determine the epidemic/epizootic vectors of RVF virus (RVFV). Approximately 297,000 mosquitoes were collected, 164,626 identified to species, 72,058 sorted into 3,003 pools and tested for RVFV by reverse transcription-polymerase chain reaction. Seventy-seven pools representing 10 species tested positive for RVFV, including Aedes mcintoshi/circumluteolus (26 pools), Aedes ochraceus (23 pools), Mansonia uniformis (15 pools); Culex poicilipes, Culex bitaeniorhynchus (3 pools each); Anopheles squamosus, Mansonia africana (2 pools each); Culex quinquefasciatus, Culex univittatus, Aedes pembaensis (1 pool each). Positive Ae. pembaensis, Cx. univittatus, and Cx. bitaeniorhynchus was a first time observation. Species composition, densities, and infection varied among districts supporting hypothesis that different mosquito species serve as epizootic/epidemic vectors of RVFV in diverse ecologies, creating a complex epidemiologic pattern in East Africa.

  18. AcEST: DK953633 [AcEST

    Lifescience Database Archive (English)

    Full Text Available 87|Q1NH87_9SPHN FAD-dependent pyridine nucleotide-disulph... 37 1.0 tr|B0W1A0|B0W1A0_CULQU Shuttle craft...VNNLDNYRDFREALPG 144 >tr|B0W1A0|B0W1A0_CULQU Shuttle craft OS=Culex quinquefasciatus GN=CpipJ_CPIJ000861 PE=

  19. EFIKASI LAMBDASIHALOTRIN (INSEKTISIDA PIRETROID TERHADAP NYAMUK VEKTOR (APLIKASI PENYEMPROTAN RUANGAN

    Directory of Open Access Journals (Sweden)

    Damar Tri Boewono

    2011-12-01

    Full Text Available ENGLISHStudy was conducted to evaluate the efficacy of Lambda-cyhalothrin (pyrethroid insecticide against mosquito vectors of dengue haemorrhagic fever /DHF Aedes aegypti and urban lymphatic filariasis Culex quinquefasciatus. Four concentrations of active ingredient 3.75, 3.13, 2.50 and 1.88 g/ha (diluted in water were evaluated for space spray, namely: thermal fog and Ultra Low Volume (ULV applications. The study revealed that Lambda-cyhalothrin (concentrations of 3.75 and 3.13 g/ha applied by using space spray methods, were effective in controlling dengue mosquito vector of Ae. aegypti (mortality 90.40-100.00%. Whereas, the concentration of 3.75 g/ha was effective against lymphatic filariasis mosquito vector of Cx.quinquefasciatus (mortality 90.00-100.00%, for both indoors and outdoors. It means that effective concentrations of lambdacyhalothrin insecticide for both space spray thermal fog and ULV methods application were more than three times of WHO recommendation 1.0 g/ha.INDONESIAPenelitian efikasi lambdasihalothrin (insektisida piretroid telah dilakukan terhadap nyamuk vektor demam berdarah dengue/DBD Aedes aegypti dan filariasis perkotaan Culex quinquefasciatus. Empat konsentrasi bahan aktif telah dievaluasi 3.75, 3.13, 2.50 dan 1.88 g/ha (dilarutkan dalam air dengan menggunakan metode aplikasi penyemprotan ruangan yaitu pengasapan (thermal fogging dan pengkabutan (Ultra Low Volume/ULV. Hasil penelitian diketahui bahwa lambdasihalotrin (konsentrasi 3.75 dan 3.13 g/ha aplikasi pengasapan dan pengkabutan, efektif membunuh nyamuk vektor DBD Ae. aegypti (kematian 90.4-100.00%. Sedangkan konsentrasi 3.75 g/ha, efektif membunuh nyamuk vektor filariasis perkotaan Cx. quinquefasciatus (kematian 90.00-100.00% baik di dalam maupun di luar rumah. Hasil tersebut menunjukkan bahwa konsentrasi insektisida lambdasihalotrin aplikasi pengasapan maupun pengkabutan, adalah lebih dari tiga kali konsentrasi yang direkomendasikan oleh WHO 1.0 g/ha.

  20. Role of wastewater irrigation in mosquito breeding in south Punjab, Pakistan

    DEFF Research Database (Denmark)

    Mukhtar, Muhammad; Herrel, Nathaly; Amerasinghe, Felix P

    2003-01-01

    and the wastewater disposal system. Overall, 17.3% of the samples were positive for Anopheles, 12.0% for Culex and 15.0% for Aedes. Four anopheline species, viz, Anopheles stephensi (84.3% of total anophelines), An. subpictus (11.8%), An. culicifacies (2.0%) and An. pulcherrimus (0.2%) were present, as were two...... species of Culex, viz, Cx. quinquefasciatus (66.5% of culicines) and Cx. tritaeniorhynchus (20.1%). Aedes were not identified to species level. The occurrence of different species was linked to particular habitats and habitat characteristics such as physical water condition, chemical water quality...... and the presence of fauna and flora. Anophelines and Aedes mosquitos were mainly collected during the month of July, while Culex were collected in September. The prevalence of established vectors of human diseases such as An. stephensi (malaria), Cx. tritaeniorhynchus (West Nile fever, Japanese encephalitis...

  1. Captura de mosquitos antropofílicos (Diptera, Culicidae em uma área urbana da região oeste da Bahia, Brasil

    Directory of Open Access Journals (Sweden)

    Isana M. dos Santos

    2014-03-01

    Full Text Available A região oeste da Bahia passa por acelerado processo de desenvolvimento agrícola, o que tem gerado problemas de infraestrutura nos municípios. A falta de saneamento básico e de coleta dos resíduos são alguns desses problemas, os quais têm papel importante no aumento de criadouros disponíveis aos culicídeos. Assim, considerando as possibilidades de contato entre vetor e população humana, o objetivo deste trabalho foi estudar a fauna de culicíeos adultos em uma área urbana no oeste da Bahia e verificar a presença de espécies de interesse em saúde pública. As amostragens de mosquitos adultos foram realizadas no município de Barreiras, de fevereiro de 2009 a janeiro de 2010, das 17h30min às 21h00min. Ao total foram capturados 1.744 mosquitos e oito gêneros foram identificados: Aedes, Coquilletidia, Culex, Limatus, Mansonia, Ochlerotatus, Psorophora e Uranotaenia. Culex quinquefasciatus foi a espécie mais frequente e abundante. Outras espécies encontradas, e que apresentam importância epidemiológica, foram Aedes aegypti e Ochlerotatus scapularis. Considerando que muitas espécies coletadas em Barreiras possuem importância epidemiológica e ocorrem mesmo durante a estação seca devido à ausência de saneamento básico, é importante que os municípios da região oeste da Bahia sejam alvo constante das atividades de vigilância epidemiológica.

  2. Potential for Co-Infection of a Mosquito-Specific Flavivirus, Nhumirim Virus, to Block West Nile Virus Transmission in Mosquitoes

    Directory of Open Access Journals (Sweden)

    Silvina Goenaga

    2015-11-01

    Full Text Available Nhumirim virus (NHUV is an insect-specific virus that phylogenetically affiliates with dual-host mosquito-borne flaviviruses. Previous in vitro co-infection experiments demonstrated prior or concurrent infection of Aedes albopictus C6/36 mosquito cells with NHUV resulted in a 10,000-fold reduction in viral production of West Nile virus (WNV. This interference between WNV and NHUV was observed herein in an additional Ae. albopictus mosquito cell line, C7-10. A WNV 2K peptide (V9M mutant capable of superinfection with a pre-established WNV infection demonstrated a comparable level of interference from NHUV as the parental WNV strain in C6/36 and C7-10 cells. Culex quinquefasciatus and Culex pipiens mosquitoes intrathoracically inoculated with NHUVandWNV, or solely withWNVas a control, were allowed to extrinsically incubate the viruses up to nine and 14 days, respectively, and transmissibility and replication of WNV was determined. The proportion of Cx. quinquefasciatus mosquitoes capable of transmitting WNV was significantly lower for the WNV/NHUV group than the WNV control at seven and nine days post inoculation (dpi, while no differences were observed in the Cx. pipiens inoculation group. By dpi nine, a 40% reduction in transmissibility in mosquitoes from the dual inoculation group was observed compared to the WNV-only control. These data indicate the potential that infection of some Culex spp. vectors with NHUV could serve as a barrier for efficient transmissibility of flaviviruses associated with human disease.

  3. Larvacidal Effect of Imperata Cylindrical Root Decoction against Culex sp. Larvae

    Directory of Open Access Journals (Sweden)

    Afini Tiara Resi

    2014-08-01

    Full Text Available Background: Filariasis is one of the neglected tropical diseases. About 337 of 401 districts in Indonesia are endemic areas for filariasis, especially in Sumatera, Kalimantan, and Papua. Culex sp. is one of the lymphatic filariasis vectors which can be controlled by insecticide, including larvacide. This study was conducted to determine the larvacidal effect of Imperata cylindrical root decoction against Culex sp. larvae. Methods: This study was conducted at the Laboratory of Parasitology, Faculty of Medicine, Universitas Padjadjaran during the period of September to November 2012. The study object was Culex sp. larvae III/IV instars. The design of this study was experimental laboratory using true experimental approach. The larvae were divided into three groups: negative control (distilled water, reference (Abate®, and decoction. The number of larvae in each group was 25 larvae, and the effects were evaluated by the total number of dead larvae in 48 hours under observation. The data were then analyzed by Mann-Whitney test and Probit test. Results: The result of the Mann-Whitney test to compare Imperata cylindrica root decoction treatment to distilled water as control was significant (p<0.05. However, Abate® gave a better result. The Probit test resultwas LC50: 63% and LC90: 489%. Conclusions: Imperata cylindrical root decoction has a larvacidal effect against Culex sp. larvae.

  4. Evaluation of bifenthrin applications in tires to prevent Aedes mosquito breeding.

    Science.gov (United States)

    Nguyen, Huy T; Whelan, Peter I; Shortus, Matthew S; Jacups, Susan P

    2009-03-01

    The efficacy of maximum label rates of bifenthrin applications to dry tires to prevent Aedes mosquito breeding was investigated by field colonization and bioassay trials in shaded and unshaded locations. Aedes notoscriptus and Culex quinquefasciatus larvae were the most abundant species present in the field colonization trial. Colonization and survival of Ae. notoscriptus larvae to the late instar occurred significantly earlier in treated tires in shaded compared with unshaded locations (P = 0.002). Bifenthrin applications in shaded tires only prevented early instar survival for approximately 2.6 wk. Aedes notoscriptus late instars did not appear in the treated unshaded tires. Culex quinquefasciatus colonized treated tires from the 2nd wk in both shaded and unshaded treatments. In the bioassay, water from bifenthrin-treated tires, through extrapolation, was found to kill approximately 100% of late instar Ae. notoscriptus for only approximately 2.0-2.2 wk in shaded and unshaded tires. Under conditions optimal for Aedes breeding, such as shaded locations, high ambient temperatures, high relative humidity, and high amounts of leaf/organic matter accumulations, bifenthrin may not be effective as a larval control measure in tires for greater than 2.0-2.6 wk.

  5. The Genus Culex, Subgenus Eumelanomyia Theobald in Southeast Asia and Adjacent Areas

    Science.gov (United States)

    1972-01-01

    Bore1 1930, Mon. Coil. Sot. Path. exot. 3: 365 (d*, ?, L*). Culex macropus Blanchard 1905, Les Moustiques :327. New name for Culex Zongifies Theobald...Spec. Pub. 111, 147 pp. BOREL, E. 1926. Les Moustiques de la Cochinchine et du Sud-Annam. (I), Arch. Inst. Pasteur d’Indochine. 47 pp. 1930. Les... Moustiques de la Cochinchine et du Sud-Annam. Mon. Coll. Sot. Pat. exot. 3, 423 pp. BRAM, R A. 1967. Contributions to the mosquitoes of Southeast Asia

  6. Spatial feeding preferences of ornithophilic mosquitoes, blackflies and biting midges

    Czech Academy of Sciences Publication Activity Database

    Černý, O.; Votýpka, Jan; Svobodová, M.

    2011-01-01

    Roč. 25, č. 1 (2011), 104-108 ISSN 0269-283X Institutional research plan: CEZ:AV0Z60220518 Keywords : Culex * Culicoides * Eusimulium * Trypanosoma * height preferences * ornithophilic Diptera Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 1.910, year: 2011

  7. Seasonal abundance and potential of Japanese encephalitis virus infection in mosquitoes at the nesting colony of ardeid birds, Thailand.

    Science.gov (United States)

    Changbunjong, Tanasak; Weluwanarak, Thekhawet; Taowan, Namaoy; Suksai, Parut; Chamsai, Tatiyanuch; Sedwisai, Poonyapat

    2013-03-01

    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. 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. 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. 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.

  8. Green synthesis of silver nanoparticles and its application for mosquito control

    Directory of Open Access Journals (Sweden)

    Naba Kumar Mondal

    2014-02-01

    Full Text Available Objective: To synthesize and characterize silver nanoparticles from aqueous root extract of Parthenium hysterophorus (P. hysterophorus and also to evaluate the potentiality of synthesized silver nanoparticles as larvacidal agent against Culex quinquefasciatus (Cx. quinquefasciatus. Methods: The silver nano particles were generated using root extract of P. hysterophorus. The characterization of synthesized nanoparticles was done by visual color change, UV-Vis spectrum, scanning electron micrograph, fluorescent microscope and Fourier transform infrared spectroscopy. Results: It was found that aqueous silver ions can be reduced by aqueous root extract of P. hysterophorus to generate extremely stable silver nanoparticles in aqueous medium. Larvae were exposed to varying concentrations of plant extracts, aqueous silver nitrate solution and synthesized silver nanoparticles for 0, 24 and 48 h separately. Aqueous root extract showed moderate larvicidal effects; however, the maximum efficacy (60.18% was observed with the synthesized silver nanoparticles against the larvae of Cx. quinquefasciatus. Conclusions: These results suggest that the green synthesis of silver nanoparticles have the potential to be used as an ideal eco-friently approach for the control of the Cx. quinquefasciatus. This is the first report on the mosquito larvicidal activity of the nano particle synthesized by P. hysterophorus.

  9. Are commercially available essential oils from Australian native plants repellent to mosquitoes?

    Science.gov (United States)

    Maguranyi, Suzann K; Webb, Cameron E; Mansfield, Sarah; Russell, Richard C

    2009-09-01

    While the use of topical insect repellents, particularly those containing synthetic active ingredients such as deet (N,N-diethyl-3-methylbenzamide), are a mainstay in personal protection strategies emphasized in public health messages, there is a growing demand in the community for alternative repellents, particularly those of botanical origin and thus deemed to be "natural." This study evaluated the repellency of essential oils from 11 Australian native plants in 5% v/v formulations against Aedes aegypti, Culex quinquefasciatus, and Culex annulirostris under laboratory conditions. A blend of the top 3 performing oils was then compared with deet and a commercially available botanical insect repellent. All essential oils provided at least some protection against the 3 mosquito species, with the longest protection time (110 min) afforded by Prostanthera melissifolia against Cx. quinquefasciatus. Mean protection times against Ae. aegypti were substantially lower than those for the Culex spp. tested. Deet provided significantly longer protection against Ae. aegypti than both the 5% v/v blend of Leptospermum petersonii, Prostanthera melissifolia, and Melaleuca alternifolia (the 3 most effective oils) and the commercial botanical repellent. The results of this study indicate that these essential oils from Australian native plants offer limited protection against biting mosquitoes and that a blend of essential oils holds may offer commercial potential as a short-period repellent or under conditions of low mosquito abundance. However, it is important that public health messages continue to emphasize the greater effectiveness of deet-based repellents in areas with risks of mosquito-borne disease.

  10. Mosquitos vetores potenciais de dirofilariose canina na Região Nordeste do Brasil Mosquitoes potential vectors of canine heartworm in the Northeast Region from Brazil

    Directory of Open Access Journals (Sweden)

    Silvia MM Ahid

    1999-12-01

    Full Text Available INTRODUÇÃO: Em alguns bairros costeiros de São Luís, Maranhão, a prevalência da dirofilariose chega a mais de 40% entre os cães domiciliados. Porém, desconhecem-se os vetores naturais, tanto lá quanto no resto do Nordeste do país. O objetivo do estudo foi identificar os prováveis vetores dessa parasitose. MÉTODOS: Realizaram-se coletas mensais de mosquitos em um bairro costeiro de São Luís, MA, de março de 1996 a maio de 1997, no peridomicílio, tendo cão e homem como iscas. Os mosquitos foram dissecados para a pesquisa de larvas da Dirofilaria immitis. RESULTADOS: Coletaram-se 1.738 mosquitos de 11 espécies. Culex quinquefasciatus, capturada todos os meses, porém menos freqüente na estação chuvosa, correspondeu a 54,5% do total, seguido de Aedes albopictus (20,3%, Aedes taeniorhynchus e Aedes scapularis (ambos 11%. Larvas de D.immitis foram encontradas em 0,1% dos Cx. quinquefasciatus e 0,5% dos Ae. taeniorhynchus. CONCLUSÕES: Ae. taeniorhynchus e Cx. quinquefasciatus foram considerados vetores potenciais da dirofilariose em São Luís. A importância local de Cx. quinquefasciatus como transmissor primário da D. immitis necessita ser melhor avaliada.INTRODUCTION: In some coastal districts of São Luís, capital of the state of Maranhão, Brazil, the prevalence of Dirofilaria immitis is more than 40% in house dogs. Natural potential vectors, as found in other areas of Northeastern Brazil, are unknown. The aim of this study was to identify probable vectors of the disease. METHODS: Mosquito catches were performed at a coastal, district Olho d'Água, in S. Luís, to look for local potential vectors. Captures were carried out monthly, from March 1996 to May 1997, outdoors, having a man and a dog as baits. Mosquitoes were dissected for D. immitis larvae. RESULTS: A total of 1,738 mosquitoes belonging to 11 species were collected. Culex quinquefasciatus, the only species collected every month, was more frequently in the dry

  11. Identification of Avian and Hemoparasite DNA in Blood-Engorged Abdomens of Culex pipiens (Diptera; Culicidae) from a West Nile Virus Epidemic region in Suburban Chicago, Illinois.

    Science.gov (United States)

    Boothe, Emily; Medeiros, Matthew C I; Kitron, Uriel D; Brawn, Jeffrey D; Ruiz, Marilyn O; Goldberg, Tony L; Walker, Edward D; Hamer, Gabriel L

    2015-05-01

    Multiple mosquito-borne parasites cocirculate in nature and potentially interact. To understand the community of parasites cocirculating with West Nile virus (WNV), we screened the bloodmeal content of Culex pipiens L. mosquitoes for three common types of hemoparasites. Blood-fed Cx. pipiens were collected from a WNV-epidemic area in suburban Chicago, IL, from May to September 2005 through 2010. DNA was extracted from dissected abdomens and subject to PCR and direct sequencing to identify the vertebrate host. RNA was extracted from the head or thorax and screened for WNV using quantitative reverse transcriptase PCR. Seventy-nine engorged females with avian host origin were screened using PCR and amplicon sequencing for filarioid nematodes, Haemosporida, and trypanosomatids. Filarioid nematodes were identified in 3.8% of the blooded abdomens, Plasmodium sp. in 8.9%, Haemoproteus in 31.6%, and Trypanosoma sp. in 6.3%. The sequences from these hemoparasite lineages were highly similar to sequences from birds in prior studies in suburban Chicago. Overall, 50.6% of blood-fed Culex pipiens contained hemoparasite DNA in their abdomen, presumably from current or prior bloodmeals. Additionally, we detected hemoparasite DNA in the blooded abdomen of three of 10 Cx. pipiens infected with WNV. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  12. Toxicity of Amorphigenin from the Seeds of Amorpha fruticosa against the Larvae of Culex pipiens pallens (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Yaping Liang

    2015-02-01

    Full Text Available The larvicidal activity of the crude petroleum ether, ethyl acetate, acetone, chloroform and ethanol extracts of Amorpha fruticosa seeds was individually assayed for toxicity against the early fourth-instar larva of the mosquito, Culex pipiens pallens after 24 h exposure. Of the tested extracts, the ethanol one exhibited the highest larvicidal activity (LC50 = 22.69 mg/L. Amorphigenin (8'-hydroxyrotenone, a rotenoid compound which exhibits a strong larvicidal activity with LC50 and LC90 values of 4.29 and 11.27 mg/L, respectively, was isolated from the ethanol extract by column chromatograpy. Its structure was elucidated by 1H-NMR, UV and IR spectral data. Furthermore, investigation of amorphigenin’s effects on mitochondrial complex I activity and protein synthesis in C. pipiens pallens larvae reveals that amorphigenin decreases mitochondrial complex I activities to 65.73% at 10.45 μmol/L, compared to the control, when NADH were used as the substrate. Meanwhile, amorphigenin at 10.45 μmol/L also caused a 1.98-fold decrease in protein content, compared to the control larvae treated with acetone only.

  13. Efficacy of alpha-cypermethrin and lambda-cyhalothrin applications to prevent Aedes breeding in tires.

    Science.gov (United States)

    Pettit, William J; Whelan, Peter I; McDonnell, Joseph; Jacups, Susan P

    2010-12-01

    The efficacy of alpha-cypermethrin (Cyperthor) and lambda-cyhalothrin (Demand) to prevent mosquito larval colonization of water-containing receptacles was investigated using 2 differing applications in disused car tires in Darwin, Australia. Insecticide treatments were applied uniformly to the inside surfaces of 2 categories of tires: 1) dry tires that were partially filled with water 24 h after spraying and 2) wet tires partially filled with water prior to spraying. All mosquito larvae, pupae, and dead adults were collected from the treatment and control tires weekly over the 24-wk study period and were later identified to species in the laboratory. Control tires were colonized by Aedes notoscriptus in wk 2 and by Culex quinquefasciatus in wk 4. Aedes notoscriptus failed to colonize any alpha-cypermethrin-treated tires until wk 22 and did not colonize any lambda-cyhalothrin-treated tires during the 24-wk trial. Culex quinquefasciatus colonized alpha-cypermethrin and lambda-cyhalothrin-treated tires from wk 11 and wk 15, respectively. These results indicate both insecticides using either application method can prevent colonization of Ae. notoscriptus for at least 20 wk and demonstrate great potential for the prevention of breeding in receptacles for other receptacle-breeding Aedes species, such as the dengue vectors, Ae. aegypti and Ae. albopictus.

  14. EVALUATION OF EXTRACTS FROM BAMBOO FOR BIOLOGICAL ACTIVITY AGAINST CULEX PIPIENS PALLENS

    Institute of Scientific and Technical Information of China (English)

    Hai-qunCao; Yong-deYue; Zhen-huaPeng; Ri-maoHua; FengTang

    2004-01-01

    The extracts from 7 species of bamboo were tested for larvicidal activity against Culex pipiens pallens. At the tested concentration, the extracts of selected bamboo had different degree of toxic effects on the fourth instar larvae of Culex pipiens pallens. Among them,the extracts of Pleioblastus juxianensis, Brachystachyum albostriatum, Phyllostachys platyglossa and Pleioblastus amarus were found to be effective with LC50values at 24h of 30.65mg/L,53.94mg/L, 41.21 mg/L and 54.49 mg/L respectively, against Culex pipiens pallens larvae. The extract of Pleioblastus juxianensis by Soxhlet method showed stronger activity than the extract obtained by interval-shaking, the LC50 of which were 30.65 mg/L and 48.34 mg/L, respectively.The diethyl ether extract of Pleioblastus juxianensis exhibited better larvicidal activity than the methanol extract and the petroleum ether extract. The results would help to provide the basis for the study of environment acceptable pesticide for mosquito control, and also help to comprehensively utilize the source of bamboo.

  15. Impact of West Nile virus dose and incubation period on vector competence of Culex nigripalpus (Diptera: Culicidae).

    Science.gov (United States)

    Richards, Stephanie L; Anderson, Sheri L; Lord, Cynthia C; Tabachnick, Walter J

    2011-11-01

    Female Culex nigripalpus were fed blood containing a low dose (6.3±0.01 logs plaque-forming units (PFU)/mL) or high dose (7.3±0.1 logs PFU/mL) of West Nile virus (WNV) and maintained at 28°C for incubation periods (IPs) of 6 or 12 days. Vector competence was measured using rates of infection (% with WNV-positive bodies), dissemination (% infected with WNV-positive legs), and transmission (% infected with WNV-positive saliva). Infection rates were not influenced by dose or IP. Dissemination rates were significantly higher at the high dose, and this was dependent on IP. Despite 100% infection and 90% dissemination in the most permissive treatment of high dose and 12 days, only 11% transmission was observed. Virus titers in body and leg tissues were significantly lower at the low dose and the titers were not influenced by IP. We show that not all mosquitoes with infections and/or disseminated infections transmit WNV under the conditions of this test. Therefore, characterizing the transmission ability of a vector population using infection or dissemination as indicators of transmission may provide inaccurate information. The complex relationships between infection, dissemination, and transmission must be evaluated under a variety of biological and environmental conditions to begin to assess the epidemiological risk of natural mosquito populations.

  16. Studies on some species of Culex (Melanoconion, with the description of a new one from Southern Brazil (Diptera: Culicidae Estudos sobre algumas espécies de Culex (Melanoconion, com a descrição de uma nova, da região meridional do Brasil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1987-04-01

    Full Text Available Redescription of Culex (Melanoconion oedipus Root and of Cx. (Mel. plectoporpe Root, as well as the description of a new one, named Cx. (Mel. rabelloi, are made. The material was collected in S.Paulo State, Southern Brazil. The descriptions include adults, pupal and larval stages, illustrating the morphological aspects and with pictures of breeding places. Some data about known distribution and bionomics are presented, remarking that all the three species seem to be closely associated with artificial manmade enviroments.Redescreve-se a espécie Culex (Melanoconion oedipus Root e Cx. (Mel. plectoporpe Root, bem como descreve-se outra nova, denominada Cx. (Mel. rabelloi. O material de estudo foi coletado no Estado de São Paulo, Brasil. As descrições incluem as formas adultas, pupais e larvais, e são acompanhadas de ilustrações representativas desses estágios, além de aspectos de criadouros naturais. Apresentam-se também alguns dados sobre a distribuição geográfica, conhecida até agora, e de comportamento dessas espécies. Assinala-se que as evidências indicam apreciável adaptabilidade desses três culicídeos ao ambiente artificial humano.

  17. EST Table: BJ984999 [KAIKOcDNA[Archive

    Lifescience Database Archive (English)

    Full Text Available from RNA polymerase II promoter)|GO:0016455(RNA polymerase II transcription mediator activity)|GO:0016592(mediator... complex) 10/09/28 43 %/186 aa ref|XP_001843810.1| mediator complex [Culex quinquefasciatus] gb|EDS34592.1| mediator...NOGA 10/09/10 39 %/196 aa gnl|Amel|GB11804-PA 10/09/10 41 %/184 aa gi|91082463|ref|XP_971521.1| PREDICTED: similar to mediator complex [Tribolium castaneum] BJ984999 mxg- ...

  18. Metofluthrin: a potent new synthetic pyrethroid with high vapor activity against mosquitoes.

    Science.gov (United States)

    Ujihara, Kazuya; Mori, Tatsuya; Iwasaki, Tomonori; Sugano, Masayo; Shono, Yoshinori; Matsuo, Noritada

    2004-01-01

    (1R)-trans-Norchrysanthemic acid fluorobenzyl esters are synthesized and their structure-activity relationships are discussed. These esters show outstanding insecticidal activity against mosquitoes. In particular, the 2,3,5,6-tetrafluoro-4-methoxymethylbenzyl analog (metofluthrin) exhibits the highest potency, being approximately forty times as potent as d-allethrin in a mosquito coil formulation when tested against southern house mosquitoes (Culex quinquefasciatus). Metofluthrin also exhibits a significant vapor action at room temperature.

  19. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus in four strains of Culex tarsalis (Diptera: Culicidae: an immunocytochemical study

    Directory of Open Access Journals (Sweden)

    Neira Oviedo MV

    2011-04-01

    Full Text Available Marco V Neira Oviedo1,2, William S Romoser1, Calvin BL James1, Farida Mahmood3, William K Reisen31Tropical Disease Institute, Department of Biomedical Sciences, College of Osteopathic Medicine, Ohio University, Athens, OH, USA; 2Oxitec Inc, Oxford, England; 3Center for Vectorborne Diseases, School of Veterinary Medicine, University of California, Davis, CA, USABackground: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV, we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion.Methods: Using immuno-stained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains – Coachella Valley, Riverside County (COAV and Kern National Wildlife Refuge (KNWR; and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP, and WEEV resistance (WR.Results and conclusions: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth

  20. Influence of Hepatozoon parasites on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens.

    Science.gov (United States)

    Ferguson, Laura V; Kirk Hillier, N; Smith, Todd G

    2013-12-01

    Hepatozoon species are heteroxenous parasites that commonly infect the blood of vertebrates and various organs of arthropods. Despite their ubiquity, little is known about how these parasites affect host phenotype, including whether or not these parasites induce changes in hosts to increase transmission success. The objectives of this research were to investigate influences of the frog blood parasite Hepatozoon clamatae and the snake blood parasite Hepatozoon sipedon on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens, respectively. During development of H. sipedon in C. pipiens, significantly fewer infected mosquitoes fed on uninfected snakes compared to uninfected mosquitoes. When H. sipedon was mature in C. pipiens, the number of infected and uninfected C. pipiens that fed on snakes was not significantly different. Higher numbers of mosquitoes fed on naturally infected snakes and frogs compared to laboratory-reared, uninfected control animals. However, experiments using only laboratory-raised frogs revealed that infection did not significantly affect host choice by C. territans. Behaviour of C. pipiens in the presence of H. sipedon may increase transmission success of the parasite and provide the first evidence of phenotypic changes in the invertebrate host of Hepatozoon parasites.

  1. Influence of Hepatozoon parasites on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens☆

    Science.gov (United States)

    Ferguson, Laura V.; Kirk Hillier, N.; Smith, Todd G.

    2012-01-01

    Hepatozoon species are heteroxenous parasites that commonly infect the blood of vertebrates and various organs of arthropods. Despite their ubiquity, little is known about how these parasites affect host phenotype, including whether or not these parasites induce changes in hosts to increase transmission success. The objectives of this research were to investigate influences of the frog blood parasite Hepatozoon clamatae and the snake blood parasite Hepatozoon sipedon on host-seeking and host-choice behaviour of the mosquitoes Culex territans and Culex pipiens, respectively. During development of H. sipedon in C. pipiens, significantly fewer infected mosquitoes fed on uninfected snakes compared to uninfected mosquitoes. When H. sipedon was mature in C. pipiens, the number of infected and uninfected C. pipiens that fed on snakes was not significantly different. Higher numbers of mosquitoes fed on naturally infected snakes and frogs compared to laboratory-reared, uninfected control animals. However, experiments using only laboratory-raised frogs revealed that infection did not significantly affect host choice by C. territans. Behaviour of C. pipiens in the presence of H. sipedon may increase transmission success of the parasite and provide the first evidence of phenotypic changes in the invertebrate host of Hepatozoon parasites. PMID:24533317

  2. Mosquitoes of the genus Culex in the Suez Canal Governorates.

    Science.gov (United States)

    Morsy, T A; el Okbi, L M; Kamal, A M; Ahmed, M M; Boshara, E F

    1990-06-01

    Mosquitoes are among the most annoying and important vectors of human and animal diseases as malaria, filariasis, yellow fever, rift valley fever...etc. In this paper, it was aimed to study the present status of species of genus Culex in the Suez Canal Governorates after the reconstruction and developmental projects. Five species of Culex were identified: C. pipiens, C. univittatus, C. antennatus, C. poicilipes and C. pusillus. The latter species was represented by two specimens. C. pipiens was the commonest species both indoors and outdoors. C. antennatus and C. poicilipes were found only outdoors. C. pipiens was found all the year round particularly in Spring. Other species were found in Spring and Autumn, except C. antennatus which was found in Summer as well. The results were discussed on the light of work done before.

  3. Evaluation in vitro de l'efficacité du fipronil sur Culex pipiens pipiens

    OpenAIRE

    Toral y Caro, Muriel

    2005-01-01

    Les moustiques sont responsables de nuisances directes et indirectes, chez l'homme et chez l'animal. C'est pourquoi il est intéressant de tester l'efficacité de nouvelles molécules sur ces insectes. Ce travail expérimental vise à tester l'efficacité potentielle du fipronil sur les moustiques appartenant au complexe Culex pipiens au moyen d'un nouveau test mis en place au laboratoire. Une première partie de ce travail est consacrée à l'étude bibliographique des caractéristiques de Culex ...

  4. Seasonal and Topographical Factors Affecting Breeding Sites of Culex Larvae in Nakhon Si Thammarat, Thailand

    OpenAIRE

    Warabhorn PREECHAPORN; Mullica JAROENSUTASINEE; Krisanadej JAROENSUTASINEE; Jirawat SAETON

    2007-01-01

    This study investigated how the seasons affect the key breeding sites of Culex larvae in three topographical areas: mangrove, rice paddy and mountainous areas. We examined how the number of Culex larvae varied in different types of water containers. Water containers were categorised into the following groups: indoor/outdoor containers, artificial/natural containers, earthen/plastic containers, containers with/without lids and dark/light coloured containers. Samples were collected from 300 hou...

  5. Identification of the temperature- induced larvicidal efficacy of Agave angustifolia against Aedes, Culex and Anopheles larvae

    Directory of Open Access Journals (Sweden)

    Mithilesh eKajla

    2016-01-01

    Full Text Available Synthetic insecticides are generally employed to control the mosquito population. However, their injudicious over usage and non-biodegradability are associated with many adverse effects on the environment and mosquitoes. The application of environment-friendly mosquitocidals might be an alternate to overcome these issues. In this study, we found that organic or aqueous extracts of Agave angustifolia leaves exhibited a strong larvicidal activity (LD50 28.27 µg/ml against Aedes aegypti, Culex quinquefasciatus and Anopheles stephensi larvae within a short exposure of 12h. The larvicidal activity of Agave angustifolia is inherited and independent of the plants vegetative growth. Interestingly, the plant larvicidal activity was observed exclusively during the summer season (April-August, when outside temperature is between 30oC to 50oC and it was significantly reduced during winter season (December-February, when the outside temperature falls to ~4oC or lower. Thus, we hypothesized that the larvicidal components of Agave angustifolia might be induced by the manipulation of environmental temperature and should be resistant to the hot conditions. We found that the larvicidal activity of Agave angustifolia was induced when plants were maintained at 37oC in a semi-natural environment against the controls that were growing outside in cold weather. Pre-incubation of Agave angustifolia extract at 100oC for 1h killed 60% larvae in 12h, which gradually increased to 100% mortality after 24h. In addition, the dry powder formulation of Agave angustifolia, also displayed a strong larvicidal activity after a long shelf life. Together, these findings revealed that Agave angustifolia is an excellent source of temperature induced bioactive metabolites that may assist the preparedness for vector control programs competently.

  6. Different toxicity of the novel Bacillus thuringiensis (Bacillales: Bacillaceae) strain LLP29 against Aedes albopictus and Culex quinquefasciatus (Diptera: Culicidae)

    Czech Academy of Sciences Publication Activity Database

    Zhang, L.; Tang, B.; Huang, E.; Huang, Z.; Liu, Z.; Huang, T.; Gelbič, Ivan; Guan, X.; Xu, L.

    2013-01-01

    Roč. 106, č. 3 (2013), s. 1098-1102 ISSN 0022-0493 Grant - others:National Natural Science Foundation of China(CN) 31071745; National Natural Science Foundation of China(CN) 31201574; Ministry of Education of China(CN) 20093515110010; Ministry of Education of China(CN) 20093515120010; Agricultural Science and Technology Achievements(CN) 2010GB2C400212; National High Technology Research and Development Program 863(CN) 2011AA10A203; Universities of Fujian Province(CN) JA12092; Fujian Agriculture and Forestry University(CN) xjq201203; Universities for the Development of the West Strait(CN) 0b08b005 Institutional research plan: CEZ:AV0Z50070508 Keywords : Bacillus thuringiensis * receptor binding * ELISA Subject RIV: ED - Physiology Impact factor: 1.605, year: 2013 http://www.bioone.org/doi/pdf/10.1603/EC12308

  7. Acaricidal, insecticidal, and larvicidal efficacy of fruit peel aqueous extract of Annona squamosa and its compounds against blood-feeding parasites.

    Science.gov (United States)

    Madhumitha, Gunabalan; Rajakumar, Govindasamy; Roopan, Selvaraj Mohana; Rahuman, Abdul Abdul; Priya, Kanagaraj Mohana; Saral, Antoneyraj Mary; Khan, Fazlur Rahman Nawaz; Khanna, Venkatesh Gopiesh; Velayutham, Kannaiyaram; Jayaseelan, Chidambaram; Kamaraj, Chinnaperumal; Elango, Gandhi

    2012-11-01

    Plant products may be alternative sources of parasitic control agents, since they constitute a rich source of bioactive compounds that are eco-friendly and nontoxic products. The plant extracts are good and safe alternatives due to their low toxicity to mammals and easy biodegradability. In the present study, fruit peel aqueous extract of Annona squamosa (Annonaceae) extracted by immersion method exhibited adulticidal activity against Haemaphysalis bispinosa (Acarina: Ixodidae) and the hematophagous fly, Hippobosca maculata (Diptera: Hippoboscidae), and larvicidal activity against the cattle tick Rhipicephalus (Boophilus) microplus (Acari: Ixodidae), Anopheles subpictus, and Culex quinquefasciatus (Diptera: Culicidae). The chemical composition of A. squamosa fruit peel aqueous extract was analyzed by gas chromatography-mass spectrometry. The major chemical constituent of peel aqueous extract of A. squamosa was identified as 1H- cycloprop[e]azulen-7-ol decahydro-1,1,7-trimethyl-4-methylene-[1ar-(1aα,4aα, 7β, 7 a, β, 7bα)] (28.55%) by comparison of mass spectral data and retention times. The other major constituents present in the aqueous extract were retinal 9-cis- (12.61%), 3,17-dioxo-4-androsten-11alpha-yl hydrogen succinate (6.86%), 1-naphthalenepentanol decahydro-5-(hydroxymethyl)-5,8a-dimethyl-y,2-bis(methylene)-(1α,4aβ,5α,8aα) (14.83%), 1-naphthalenemethanol decahydro -5-(5-hydroxy-3-methyl-3-pentenyl)- 1,4a-di methyl - 6-methylene -(1S-[1α, 4aα, 5α(E), 8aβ] (4.44%), (-)-spathulenol (20.75%), podocarp-7-en-3-one13β-methyl-13-vinyl- (5.98%), and 1-phenanthrene carboxaldehyde 7-ethenyl-1,2,3,4,4a,4,5,6,7,9,10,10a-dodecahydro-1,4a,7-trimethyl-[1R-(1α,4aβ.4bα,7β, 10aα)]-(5.98%). The adult and larval parasitic mortalities observed in fruit peel aqueous extract of A. squamosa were 31, 59, 80, 91, and100%; 27, 42, 66, 87, and 100%; and 33, 45, 68, 92, and 100% at the concentrations of 250, 500, 1,000, 1,500, and 2,000 ppm, respectively, against

  8. Attractiveness of MM-X Traps Baited with Human or Synthetic Odor to Mosquitoes (Diptera: Culicidae) in The Gambia

    Science.gov (United States)

    QIU, YU TONG; SMALLEGANGE, RENATE C.; TER BRAAK, CAJO J. F.; SPITZEN, JEROEN; VAN LOON, JOOP J. A.; JAWARA, MUSA; MILLIGAN, PAUL; GALIMARD, AGNES M.; VAN BEEK, TERIS A.; KNOLS, BART G. J.; TAKKEN, WILLEM

    2013-01-01

    Chemical cues play an important role in the host-seeking behavior of blood-feeding mosquitoes (Diptera: Culicidae). A field study was carried out in The Gambia to investigate the effects of human odor or synthetic odor blends on the attraction of mosquitoes. MM-X traps baited with 16 odor blends to which carbon dioxide (CO2) was added were tested in four sets of experiments. In a second series of experiments, MM-X traps with 14 odor blends without CO2 were tested. A blend of ammonia and l-lactic acid with or without CO2 was used as control odor in series 1 and 2, respectively. Centers for Disease Control and Prevention (CDC) traps were placed in a traditional house and an experimental house to monitor mosquito densities during the experiments. The MM-X traps caught a total number of 196,756 mosquitoes, with the most abundant species belonging to the genera Mansonia (70.6%), Anopheles (17.5%), and Culex (11.5%). The most abundant mosquito species caught by the CDC traps (56,290 in total) belonged to the genera Mansonia (59.4%), Anopheles (16.0% An. gambiae s.l. Giles, and 11.3% An. ziemanni Grünberg), and Culex (11.6%). MM-X traps baited with synthetic blends were in many cases more attractive than MM-X traps baited with human odors. Addition of CO2 to synthetic odors substantially increased the catch of all mosquito species in the MM-X traps. A blend of ammonia + L-lactic acid + CO2 + 3-methylbutanoic acid was the most attractive odor for most mosquito species. The candidate odor blend shows the potential to enhance trap collections so that traps will provide better surveillance and possible control. PMID:18047195

  9. Species\\' identification of Anopheles and Culex mosquitoes and its ...

    African Journals Online (AJOL)

    Indoor and outdoor bites' collections of gravid Anopheles and Culex mosquitoes were made with plastic aspirator from residential areas within Jimeta-Yola metropolis for three years (between March and May; August and October 2003 to 2005). They were identified using standard morphological keys and polymerase chain ...

  10. Potential topical natural repellent against Ae. aegypti, Culex sp. and Anopheles sp. mosquitoes

    Directory of Open Access Journals (Sweden)

    Dewi Nur Hodijah

    2014-08-01

    Full Text Available AbstrakLatar belakang:Minyak atsiri daun sirih diketahui mempunyai daya proteksi. Dibuatkan losion berdasarkan pengantar sediaan farmasi yang ditambahkan minyak atsiri daun nilam. Sediaan losion dipilih agar dapat menempel lebih lama di permukaan kulit. Tujuan penelitian ini untuk membandingkan daya proteksi antara losion dengan penambahan minyak nilam dan losion tanpa penambahan minyak nilam dibandingkan daya proteksi dengan DEET. Metode: Penelitian ini merupakan penelitian eksperimental laboratorium. Semua nyamuk uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Konsentrasi minyak atsiri daun sirih dalam losion adalah 4%; konsentrasi minyak nilam sebagai zat pengikat adalah 0,4%. Formula yang digunakan yaitu formula dasar yang ada pada pengantar sediaan farmasi. Uji repelensi dilakukan dengan menggunakan metoda yang direkomendasikan oleh Komisi pestisida.Hasil: Dihasilkan formulasi losion yang stabil dan masih memenuhi standar formulasi sediaan. Berdasarkan hasil, diperoleh data bahwa DEET dan losion hasil modifikasi memiliki rata-rata daya proteksi di atas 90% selama 6 jam terhadap nyamuk Ae.aegypti dan Culex sp. Kesimpulan: Penambahan minyak nilam pada losion sirih dapat meningkatkan daya proteksi terhadap hinggapan nyamuk Ae. aegypti dan Culex sp. (Health Science Indones 2014;1:44-8Kata kunci:repelen alamiah, minyak atsiri, daun sirih, daun nilam, Ae. aegypti, Culex sp.AbstractBackground: Betel leaf essential oil lotion has been known to have insect repellent properties. A lotion was made based on a pharmaceutical formula from a monograph where patchouli leaf essential oil was added. A lotion preparation was intended to enhance adherence of the formula on the surface of the skin. The purpose of this study was to compare protection percentage of lotion with patchouli oil and without patchouli oil lotion compared to DEET.Methods: This study is an experimental laboratory-based research. All mosquitoes

  11. Diptera: Agromyzidae

    African Journals Online (AJOL)

    Yomi

    2012-01-31

    Jan 31, 2012 ... This study was conducted to develop sequential sampling plans to estimate larval density of Liriomyza sativae Blanchard (Diptera: Agromyzidae) at three precision levels in cucumber greenhouse. The within- greenhouse spatial patterns of larvae were aggregated. The slopes and intercepts of both Iwao's.

  12. Efectos de la competencia larval en los mosquitos de contenedores artificiales, Aedes aegypti y Culex pipiens (Diptera: Culicidae en condiciones semi-controladas Effects of larval competition between the container mosquitoes, Aedes aegypti and Culex pipiens (Diptera: Culicidae in semi-controlled conditions

    Directory of Open Access Journals (Sweden)

    Analía Francia

    2011-12-01

    Full Text Available Las larvas de los mosquitos Aedes aegypti (Linneo y Culex pipiens Linneo pueden criar conjuntamente en pequeños contenedores artificiales de agua, se genera así una competencia interespecífica y/o intraespecífica. El objetivo de este trabajo fue comparar la magnitud relativa de la competencia intra e interespecífica en A. aegypti y C. pipiens, generada durante el desarrollo larval en contenedores artifi ciales. Las variables medidas como respuesta fueron la supervivencia y el tiempo de desarrollo larval, y la biomasa total producida en estado de pupa. Se criaron larvas de ambos mosquitos en neumáticos de automóvil con agua declorinada y hojarasca. Se introdujeron larvas recién eclosionadas de acuerdo a la densidad (5 estimada según un censo previo de A. aegypti y C. pipiens. Serealizaron los siguientes tratamientos agregando larvas de: (1 A. aegypti hasta alcanzar δ A. aegypti determinada según el censo previo, (2 C. pipiens hasta δ C. pipiens del censo previo, (3 A. aegypti hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo, (4 C. pipiens hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo y (5 A. aegypti y C. pipiens hasta δ A. aegypti y δ C. pipiens del censo previo. Las tres variables medidas fueron afectadas por los tratamientos, excepto la supervivencia y la biomasa producida por C. pipiens. Aedes aegypti fue más alterada por la competencia intraespecífica que por la competencia interespecífica. En C. pipiens, la competencia interespecífica superó en sus efectos a la competencia intraespecífica. Existió asimetría competitiva, ya que C. pipiens fue más afectada por A. aegypti que lo contrario.Larvae of Aedes aegypti (Linneo and Culex pipiens Linneo may develop together in small artificial water containers, promoting inter- and/or intra-specific competition. Our aim was to compare the relative importance of interspecific and intraspecific competition in both species during

  13. Biocontrol of larval mosquitoes by Acilius sulcatus (Coleoptera: Dytiscidae

    Directory of Open Access Journals (Sweden)

    Banerjee Siddhartha S

    2008-10-01

    Full Text Available Abstract Background Problems associated with resistant mosquitoes and the effects on non-target species by chemicals, evoke a reason to find alternative methods to control mosquitoes, like the use of natural predators. In this regard, aquatic coleopterans have been explored less compared to other insect predators. In the present study, an evaluation of the role of the larvae of Acilius sulcatus Linnaeus 1758 (Coleoptera: Dytiscidae as predator of mosquito immatures was made in the laboratory. Its efficacy under field condition was also determined to emphasize its potential as bio-control agent of mosquitoes. Methods In the laboratory, the predation potential of the larvae of A. sulcatus was assessed using the larvae of Culex quinquefasciatus Say 1823 (Diptera: Culicidae as prey at varying predator and prey densities and available space. Under field conditions, the effectiveness of the larvae of A. sulcatus was evaluated through augmentative release in ten cemented tanks hosting immatures of different mosquito species at varying density. The dip density changes in the mosquito immatures were used as indicator for the effectiveness of A. sulcatus larvae. Results A single larva of A. sulcatus consumed on an average 34 IV instar larvae of Cx. quinquefasciatus in a 24 h period. It was observed that feeding rate of A. sulcatus did not differ between the light-on (6 a.m. – 6 p.m., and dark (6 p.m. – 6 a.m. phases, but decreased with the volume of water i.e., space availability. The prey consumption of the larvae of A. sulcatus differed significantly (P A. sulcatus larvae, while with the withdrawal, a significant increase (p A. sulcatus in regulating mosquito immatures. In the control tanks, mean larval density did not differ (p > 0.05 throughout the study period. Conclusion the larvae of the dytiscid beetle A. sulcatus proved to be an efficient predator of mosquito immatures and may be useful in biocontrol of medically important mosquitoes.

  14. Laboratory evaluation of methanolic extract of Atlantia monophylla (Family: Rutaceae against immature stages of mosquitoes and non-target organisms

    Directory of Open Access Journals (Sweden)

    N Sivagnaname

    2004-02-01

    Full Text Available Methanolic extracts of the leaves of Atlantia monophylla (Rutaceae were evaluated for mosquitocidal activity against immature stages of three mosquito species, Culex quinquefasciatus, Anopheles stephensi, and Aedes aegypti in the laboratory.Larvae of Cx. quinquefasciatus and pupae of An. stephensi were found more susceptible, with LC50 values of 0.14 mg/l and 0.05 mg/l, respectively. Insect growth regulating activity of this extract was more pronounced against Ae. aegypti, with EI50 value 0.002 mg/l. The extract was found safe to aquatic mosquito predators Gambusia affinis, Poecilia reticulata, and Diplonychus indicus, with the respective LC50 values of 23.4, 21.3, and 5.7 mg/l. The results indicate that the mosquitocidal effects of the extract of this plant were comparable to neem extract and certain synthetic chemical larvicides like fenthion, methoprene, etc.

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

    Directory of Open Access Journals (Sweden)

    Muhammad Ashfaq

    Full Text Available 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.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.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.

  16. Field trial of the spatial repellency of metofluthrin-impregnated plastic strip against mosquitoes in shelters without walls (Beruga) in Lombok, Indonesia.

    OpenAIRE

    Kawada, Hitoshi; Maekawa, Yoshihide; Takagi, Masahiro

    2005-01-01

    Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for ...

  17. Feeding patterns of molestus and pipiens forms of Culex pipiens (Diptera: Culicidae) in a region of high hybridization.

    Science.gov (United States)

    Gomes, Bruno; Sousa, Carla A; Vicente, José L; Pinho, Leonor; Calderón, Isabel; Arez, Eliane; Almeida, António Pg; Donnelly, Martin J; Pinto, João

    2013-04-11

    Two biological forms of the mosquito Culex pipiens s.s., denoted pipiens and molestus, display behavioural differences that may affect their role as vectors of arboviruses. In this study, the feeding patterns of molestus and pipiens forms were investigated in Comporta (Portugal), where high levels of inter-form admixture have been recorded. Indoor and outdoor mosquito collections were performed in the summer of 2010. Collected Cx. pipiens s.l. females were molecularly identified to species and form by PCR and genotyped for six microsatellites. The source of the blood meal in post-fed females was determined by ELISA and mitochondrial DNA sequencing. The distribution of the forms differed according to the collection method. The molestus form was present only in indoor collections, whereas pipiens and admixed individuals were sampled both indoors and outdoors. In both forms, over 90% of blood meals were made on avian hosts. These included blood meals taken from Passeriformes (Passer domesticus and Turdus merula) by females caught resting inside domestic shelters. Genetic structure and blood meal analyses suggest the presence of a bird biting molestus population in the study area. Both forms were found to rest indoors, mainly in avian shelters, but at least a proportion of females of the pipiens form may bite outdoors in sylvan habitats and then search for anthropogenic resting sites to complete their gonotrophic cycle. This behaviour may potentiate the accidental transmission of arboviruses to humans in the region.

  18. Comments on the association of immatures of Hemerodromia (Diptera, Empididae) and Simulium (Diptera, Simuliidae), and first record of this association in the Atlantic Forest (Brazil).

    Science.gov (United States)

    Sánchez Molina, Óscar; Gil-Azevedo, Leonardo Henrique

    2016-11-01

    Larvae of Empididae (Diptera) prey on black fly immatures and its pupae can be collected from pupal cases of Simuliidae (Diptera). The aim of our work was to report the second record of association between immatures of Empididae and Simuliidae in the Neotropical Region and the first for the Atlantic Forest (Rio de Janeiro, Brazil). We collected 4982 pupae and exuviae of Simulium Latreille, (Diptera, Simuliidae) and found three with a pupa of Hemerodromia Meigen (Diptera, Empididae) inside. This shows that the use of black flies cocoons by dance flies occurs at extremely low frequencies, which might explain why this association is so rarely recorded. Our results are relevant for a better comprehension of the predator-prey relationship between these families. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Culex coronator in coastal Georgia and South Carolina.

    Science.gov (United States)

    Moulis, Robert A; Russell, Jennifer D; Lewandowski, Henry B; Thompson, Pamela S; Heusel, Jeffrey L

    2008-12-01

    In 2007, adult Culex coronator were collected in Chatham County, Georgia, and Jasper County, South Carolina, during nuisance and disease vector surveillance efforts. A total of 75 specimens of this species were collected at 8 widely separated locations in Chatham County, Georgia, and 4 closely situated sites in Jasper County, South Carolina. These represent the first Atlantic coastal records of this species in Georgia and the first confirmed records of Cx. coronator in South Carolina.

  20. Diptera: Tephritidae

    African Journals Online (AJOL)

    SAM

    2014-03-19

    Mar 19, 2014 ... Wiedemann (Diptera: Tephritidae). Flávia Queiroz de Oliveira1*, José Bruno Malaquias2, Wennia Rafaelly de Souza Figueiredo3,. Jacinto de Luna Batista4, Eduardo Barbosa Beserra1 and Robério de Oliveira4. 1Universidade Estadual da Paraíba (UEPB), campus I/Campina Grande, Bodocongó, Paraíba, ...

  1. Pond dyes are Culex mosquito oviposition attractants

    Directory of Open Access Journals (Sweden)

    Natali Ortiz Perea

    2017-05-01

    Full Text Available Background British mosquito population distribution, abundance, species composition and potential for mosquito disease transmission are intimately linked to the physical environment. The presence of ponds and water storage can significantly increase the density of particular mosquito species in the garden. Culex pipiens is the mosquito most commonly found in UK gardens and a potential vector of West Nile Virus WNV, although the current risk of transmission is low. However any factors that significantly change the distribution and population of C. pipiens are likely to impact subsequent risk of disease transmission. Pond dyes are used to control algal growth and improve aesthetics of still water reflecting surrounding planting. However, it is well documented that females of some species of mosquito prefer to lay eggs in dark water and/or containers of different colours and we predict that dyed ponds will be attractive to Culex mosquitoes. Methods Black pond dye was used in oviposition choice tests using wild-caught gravid C. pipiens. Larvae from wild-caught C. pipiens were also reared in the pond dye to determine whether it had any impact on survival. An emergence trap caught any adults that emerged from the water. Water butts (80 L were positioned around university glasshouses and woodland and treated with black pond dye or left undyed. Weekly sampling over a six month period through summer and autumn was performed to quantified numbers of larvae and pupae in each treatment and habitat. Results Gravid female Culex mosquitoes preferred to lay eggs in dyed water. This was highly significant in tests conducted under laboratory conditions and in a semi-field choice test. Despite this, survivorship in black dyed water was significantly reduced compared to undyed water. Seasonal analysis of wild larval and pupal numbers in two habitats with and without dye showed no impact of dye but a significant impact of season and habitat. Mosquitoes were more

  2. Entomological surveillance, spatial distribution, and diversity of Culicidae (Diptera) immatures in a rural area of the Atlantic Forest biome, State of São Paulo, Brazil.

    Science.gov (United States)

    Piovezan, Rafael; Rosa, Stéfany Larissa; Rocha, Matheus Luca; de Azevedo, Thiago Salomão; Von Zuben, Cláudio José

    2013-12-01

    Because of the high adaptive capacity of mosquitoes, studies that focus on transitional environments become very important, such as those in rural areas, which are considered as bridges between wild diseases and human populations of urban areas. In this study, a survey of the existing species of mosquitoes was performed in an Atlantic Forest area of the city of Santa Bárbara d'Oeste, São Paulo state, Brazil, using traps for immatures and analyzing the frequency and distribution of these insects over the sampling months. Five mosquito species were found: Aedes albopictus (the most frequent species), Aedes aegypti, Aedes fluviatilis, Culex quinquefasciatus, and Toxorhynchites theobaldi. The 4,524 eggs collected in ovitraps showed the presence of the tribe Aedini. Aedes aegypti and Ae. albopictus were identified after larval hatching in the laboratory, with different spatial distributions: the first of which coincides with the area of greatest diversity calculated using the Simpson index, while the second does not. The association of ecological analysis of spatial diversity with simple methods of data collection enables the identification of possible epidemiological risk situations and is a strategy that may be implemented to monitor ecological processes resulting from the interaction among different species of mosquitoes. © 2013 The Society for Vector Ecology.

  3. Urbanization impact on mosquito community and the transmission potential of filarial infection in central Europe

    Czech Academy of Sciences Publication Activity Database

    Čabanová, V.; Miterpáková, M.; Valentová, D.; Blažejová, Hana; Rudolf, Ivo; Stloukal, E.; Hurníková, Z.; Dzidová, M.

    2018-01-01

    Roč. 11, č. 1 (2018), č. článku 261. ISSN 1756-3305 Institutional support: RVO:68081766 Keywords : Culex pipiens complex * West Nile virus * Diptera Culicidae * Anopheles hyrcanus * Dirofilaria immitis * Aedes albopictus * endemic area * 1st record * Slovakia * vector * Dirofilaria * mosquito-borne diseases * Anopheles maculipennis complex * xenomonitoring Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 3.080, year: 2016

  4. Enkapsulasi B. bassiana menggunakan maizena dan daya infeksinya terhadap larva Aedes aegypti, Anopheles sp., Culex sp.

    Directory of Open Access Journals (Sweden)

    Mutiara Widawati

    2015-12-01

    Full Text Available Abstract. Encapsulation formulae of mycoinsecticide have to be able to maintain fungus viability and pathogenicity. This mycoinsecticide was developed as an alternative way to control mosquito borne disease. The aim of this study was to encapsulate Beauveria bassiana as viable storage and have the capability to kill larvae of Aedes aegypti, Anopheles sp. and Culex sp. Mosquito larvae obtained from laboratory reared at health research laboratory; Loka Litbang P2B2 Ciamis. The treatments made in this study were the formu-lation of cornstarch and controls for comparison. This study showed potential formulation of cornstarch encapsulation as a biolarvacidal. Cornstarch formulations proven to be succeed in maintaining fungus viability, however, the pathogenicity of the microcapsule still not effective to kill Aedes, Culex and Anopheles larvae. Keywords: encapsulation, Beauveria bassiana, Ae.aegypti, Anopheles sp., Culex sp. Abstrak. Pembuatan formula bioinsektisida yang optimal sebagai salah satu alternatif untuk pengen-dalian nyamuk vektor perlu di kembangkan. Sediaan mikoinsektisida yang dibuat harus dapat memper-tahankan viabilitas jamur B. bassiana sehingga masih efektif pada saat penggunaannya. Salah satu cara yang digunakan untuk menjaga kestabilan sediaan mikoinsektisida yang berdampak langsung pada via-bilitas jamur adalah dengan menerapkan metode enkapsulasi. Penelitian ini bertujuan untuk meng-hasilkan sediaan mikokapsul dari Beauvaria bassiana melalui proses enkapsulasi menggunakan maizena yang memiliki kapabilitas tinggi sebagai penyimpan B. bassiana dan efektif dalam membunuh larva dan telur Aedes aegypti, Anopheles sp. dan Culex sp. Semua larva uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Pembuatan enkapsulasi dimulai dengan kultur dan pema-nenan B. bassiana, uji viabilitas, proses enkapsulasi serta uji larvasida di laboratorium. Uji dilakukan dengan satu perlakuan dan satu kontrol untuk

  5. Occurrence of avian Plasmodium and West Nile virus in culex species in Wisconsin

    Science.gov (United States)

    Hughes, T.; Irwin, P.; Hofmeister, E.; Paskewitz, S.M.

    2010-01-01

    The occurrence of multiple pathogens in mosquitoes and birds could affect the dynamics of disease transmission. We collected adult Culex pipiens and Cx. restuans (Cx. pipiens/restuans hereafter) from sites in Wisconsin and tested them for West Nile virus (WNV) and for avian malaria (Plasmodium). Gravid Cx. pipiens/restuans were tested for WNV using a commercial immunoassay, the RAMP?? WNV test, and positive results were verified by reverse transcriptasepolymerase chain reaction. There were 2 WNV-positive pools of Cx. pipiens/restuans in 2006 and 1 in 2007. Using a bias-corrected maximum likelihood estimation, the WNV infection rate for Cx. pipiens/restuans was 5.48/1,000 mosquitoes in 2006 and 1.08/1,000 mosquitoes in 2007. Gravid Cx. pipiens or Cx. restuans were tested individually for avian Plasmodium by a restriction enzymebased assay. Twelve mosquitoes were positive for avian Plasmodium (10.0), 2 were positive for Haemoproteus, and 3 were positive for Leucocytozoon. There were 4 mixed infections, with mosquitoes positive for >1 of the hemosporidian parasites. This work documents a high rate of hemosporidian infection in Culex spp. and illustrates the potential for co-infections with other arboviruses in bird-feeding mosquitoes and their avian hosts. In addition, hemosporidian infection rates may be a useful tool for investigating the ecological dynamics of Culex/avian interactions. ?? 2010 by The American Mosquito Control Association, Inc.

  6. Ecological niche modelling of Rift Valley fever virus vectors in Baringo, Kenya

    Directory of Open Access Journals (Sweden)

    Alfred O. Ochieng

    2016-11-01

    Full Text Available Background: Rift Valley fever (RVF is a vector-borne zoonotic disease that has an impact on human health and animal productivity. Here, we explore the use of vector presence modelling to predict the distribution of RVF vector species under climate change scenario to demonstrate the potential for geographic spread of Rift Valley fever virus (RVFV. Objectives: To evaluate the effect of climate change on RVF vector distribution in Baringo County, Kenya, with an aim of developing a risk map for spatial prediction of RVF outbreaks. Methodology: The study used data on vector presence and ecological niche modelling (MaxEnt algorithm to predict the effect of climatic change on habitat suitability and the spatial distribution of RVF vectors in Baringo County. Data on species occurrence were obtained from longitudinal sampling of adult mosquitoes and larvae in the study area. We used present (2000 and future (2050 Bioclim climate databases to model the vector distribution. Results: Model results predicted potential suitable areas with high success rates for Culex quinquefasciatus, Culex univitattus, Mansonia africana, and Mansonia uniformis. Under the present climatic conditions, the lowlands were found to be highly suitable for all the species. Future climatic conditions indicate an increase in the spatial distribution of Cx. quinquefasciatus and M. africana. Model performance was statistically significant. Conclusion: Soil types, precipitation in the driest quarter, precipitation seasonality, and isothermality showed the highest predictive potential for the four species.

  7. Registro de Culicidae de importância epidemiológica na área rural de Manaus, Amazonas Record of epidemiologically important Culicidae in the rural area of Manaus, Amazonas

    Directory of Open Access Journals (Sweden)

    Maria das Graças Vale Barbosa

    2008-12-01

    Full Text Available A biodiversidade da Região Amazônica inclui diversas espécies de vetores artrópodes em seus diferentes ecótopos, possibilitando o surgimento de doenças como malária, filarioses e arboviroses. De agosto de 2001 a julho de 2002, realizou-se coletas de culicídeos no domicílio, peridomicílio e nas matas da Comunidade São João, área rural de Manaus, Amazonas. Foram capturados 1.240 culicídeos, pertencentes às subfamílias Culicinae (99% e Anophelinae (1%, somando 50 espécies. O predomínio entre as tribos foi nitidamente de Culicini, com 904 (72,9% exemplares, destacando-se as espécies Culex usquatus (22,6% e Culex quinquefasciatus (17,7%. Do total de culicídeos, 1.077 (86,9% exemplares foram capturados no interior das matas, 101 (8,1% no peridomicílio e 62 (5% no intradomicílio. O ecótopo com maior diversidade de espécies foi a mata. Assinalou-se a presença de Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus janthinomys e outros vetores comprovados ou potenciais.The biodiversity of the Amazon region includes many species of arthropod vectors in different ecotopes, thus enabling occurrences of diseases like malaria, filariasis and arbovirosis. From August 2001 to July 2002, we gathered culicids from inside homes, from areas surrounding these homes and from forested areas of the São João Community, in the rural zone of Manaus, State of Amazonas. 1240 specimens were collected, belonging to the Culicinae (99% and Anophelinae (1% subfamilies, with 50 species. The Culicini tribe clearly predominated, with 904 specimens (72.9%, and the species Culex usquatus (22.6% and Culex quinquefasciatus (17.7% were prominent. Out of the total number of culicids, 1,077 (86.9% were caught in the forests, 101 (8.1% in the areas surrounding homes and 62 (5% inside homes. Forests were the ecotope that presented the highest species diversity. The presence of Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus

  8. Larvicidal efficacies and chemical composition of essential oils of Pinus sylvestris and Syzygium aromaticum against mosquitoes.

    Science.gov (United States)

    Fayemiwo, Kehinde Adenike; Adeleke, Monsuru Adebayo; Okoro, Ovie Princewill; Awojide, Shola Hezekiah; Awoniyi, Ilias Olufemi

    2014-01-01

    To assess the chemical composition and mosquito larvicidal potentials of essential oils of locally sourced Pinus sylvestris (P. sylvestris) and Syzygium aromaticum (S. aromaticum) against Aedes aegypti (A. aegypti) and Culex quinquefasciatus (C. quinquefasciatus). The chemical composition of the essential oils of both plants was determined using GC-MS while the larvicidal bioassay was carried out using different concentrations of the oils against the larvae of A. aegypti and C. quinquefasciatus in accordance with the standard protocol. The results as determined by GC-MS showed that oil of S. aromaticum has eugenol (80.5%) as its principal constituent while P. sylvestris has 3-Cyclohexene-1-methanol, .alpha., .alpha.4-trimethyl (27.1%) as its dominant constituent. Both oils achieved over 85% larval mortality within 24 h. The larvae of A. aegypti were more susceptible to the oils [LC50 (S. aromaticum)=92.56 mg/L, LC50(P. sylvestris)=100.39 mg/L] than C. quinquefasciatus [LC50(S. aromaticum)=124.42 mg/L; LC50(P. sylvestris)=128.00 mg/L]. S. aromaticum oil was more toxic to the mosquito larvae than oil of P. sylvestris but the difference in lethal concentrations was insignificant (P>0.05). The results justify the larvicidal potentials of both essential oils and the need to incorporate them in vector management and control. Copyright © 2014 Asian Pacific Tropical Biomedical Magazine. Published by Elsevier B.V. All rights reserved.

  9. Efficacy of Bacillus thuringiensis var israelinsis (Bti) on Culex and ...

    African Journals Online (AJOL)

    dosage that can be used to control Culex mosquito larvae in Zomba after ... exposed to the same dosage of liquid formulation of Bti (0.001ml/L) there ... The objective of this study was to evaluate the efficacy of Bti on mosquito ...... In short Bti whether liquid or granular is very important as it significantly reduces the densities of ...

  10. Enhanced Tolerance of House Mosquito to Different Insecticides due to Agricultural and Household Pesticides in Sewage System of Tehran, Iran

    Directory of Open Access Journals (Sweden)

    H Vatandoost, L Ezeddinloo, A H Mahvi, M R Abai, EB Kia, I Mobedi

    2004-07-01

    Full Text Available Different insecticides are being used for household and agricultural pest control in the capital city of Iran, Tehran. An investigation was carried out in order to evaluate the susceptibility level of laboratory and field collected mosquito, Culex quinquefasciatusin to different insecticides. Field strain was collected from sewage system of the city. Adult females were subjected to the diagnostic dose of different insecticides as recommended by WHO. Results showed that laboratory strains only exhibit resistant to DDT 4%, and susceptible to other insecticides. By using WHO criteria, field strain is resistant to DDT 4%, bendiocarb 0.1%, and tolerant to malathion 5%, permethrin 0.75%, deltamethrin 0.05%, lambdacyhalothrin 0.05% and etofenprox 5%. The field strain is still susceptible to cyfluthrin 0.15%.This findings indicate that routine use of pesticides in household and agricultural pest control may cause resistant in the wastewater mosquito, Culex quinquefasciatus.

  11. Lethal Effects of Aspergillus niger against Mosquitoes Vector of Filaria, Malaria, and Dengue: A Liquid Mycoadulticide

    Directory of Open Access Journals (Sweden)

    Gavendra Singh

    2012-01-01

    Full Text Available Aspergillus niger is a fungus of the genus Aspergillus. It has caused a disease called black mold on certain fruits and vegetables. The culture filtrates released from the A. niger ATCC 66566 were grown in Czapek dox broth (CDB then filtered with flash chromatograph and were used for the bioassay after a growth of thirty days. The result demonstrated these mortalities with LC50, LC90, and LC99 values of Culex quinquefasciatus 0.76, 3.06, and 4.75, Anopheles stephensi 1.43, 3.2, and 3.86, and Aedes aegypti 1.43, 2.2, and 4.1 μl/cm2, after exposure of seven hours. We have calculated significant LT90 values of Cx. quinquefasciatus 4.5, An. stephensi 3.54, and Ae. aegypti 6.0 hrs, respectively. This liquid spray of fungal culture isolate of A. niger can reduce malaria, dengue, and filarial transmission. These results significantly support broadening the current vector control paradigm beyond chemical adulticides.

  12. Green synthesis of silver nanoparticles for the control of mosquito vectors of malaria, filariasis, and dengue.

    Science.gov (United States)

    Arjunan, Naresh Kumar; Murugan, Kadarkarai; Rejeeth, Chandrababu; Madhiyazhagan, Pari; Barnard, Donald R

    2012-03-01

    A biological method was used to synthesize stable silver nanoparticles that were tested as mosquito larvicides against Aedes aegypti, Anopheles stephensi, and Culex quinquefasciatus. Annona squamosa leaf broth (5%) reduced aqueous 1 mM AgNO₃ to stable silver nanoparticles with an average size of 450 nm. The structure and percentage of synthesized nanoparticles was characterized by using ultraviolet spectrophotometry, X-Ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy methods. The median lethal concentrations (LC₅₀) of silver nanoparticles that killed fourth instars of Ae. aegypti, Cx. quinquefasciatus, and An. stephensi were 0.30, 0.41, and 2.12 ppm, respectively. Adult longevity (days) in male and female mosquitoes exposed as larvae to 0.1 ppm silver nanoparticles was reduced by ~30% (p<0.05), whereas the number of eggs laid by females exposed as larvae to 0.1 ppm silver nanoparticles decreased by 36% (p<0.05).

  13. Bioactive compound synthesis of Ag nanoparticles from leaves of Melia azedarach and its control for mosquito larvae.

    Science.gov (United States)

    Ramanibai, R; Velayutham, K

    2015-02-01

    Larvicidal activity of synthesized Ag nanoparticles using 2,7.bis[2-[diethylamino]-ethoxy]fluorence isolate from the Melia azedarach leaves against Aedes aegypti and Culex quinquefasciatus. Six fractions were collected and concentrated, fraction three showed a single spot on TLC which was found to be a pure compound. The structures were elucidated by analyses of UV, MS, and NMR spectral data. The maximum mortality was fluorence against A. aegypti and C. quinquefasciatus (LC50 = 7.94, LC90 = 23.82 ppm and LC50 = 13.58 and LC90 = 40.03 ppm). The synthesized nanoparticles were characterized and confirmed as Ag nanoparticles by using UV-visible spectroscopy, XRD and HRTEM analysis. The maximum activity was observed in synthesized AgNPs against A. aegypti and C. quinquefasciatus (LC50 = 4.27 and 3.43 µg/mL; LC90 = 12.61 and 10.29 µg/mL). Rephrase test was studied to analyze the toxicological effects of Mesocyclops pehpeiensis for 24 h at synthesized AgNPs. This method is considered as an innovative alternative approach that can be used to control mosquitoes. Copyright © 2014. Published by Elsevier Ltd.

  14. O aproveitamento do resíduo da indústria do sisal no controle de larvas de mosquitos

    Directory of Open Access Journals (Sweden)

    Pizarro Ana Paula B.

    1999-01-01

    Full Text Available Descreve-se o aproveitamento do resíduo do desfibramento das folhas de Agave sisalana, como um larvicida para o combate a mosquitos transmissores de doenças tropicais. Durante 24 horas, larvas de Aedes aegypti e Culex quinquefasciatus foram expostas a concentrações diferentes do extrato da planta para determinar as concentrações letais. Para A. aegypti foi constatada a CL50 em 322ppm e para C. quinquefasciatus em 183ppm. Foi investigada a ação de saponinas existentes na planta, ficando evidenciado que o resíduo de A. sisalana é ativo através da interação de vários dos seus componentes. Este extrato poderá ser utilizado em campo, na concentração de 100ppm para C. quinquefasciatus com um aumento do tempo de exposição para três dias, obtendo-se uma mortalidade de 100% das larvas. Este produto, porém, não é recomendado para o controle de A. aegypti, devido à necessidade de uma alta concentração para a obtenção de 100% de mortalidade das larvas e ao fato destas se desenvolverem preferencialmente em água potável.

  15. Zika virus: An updated review of competent or naturally infected mosquitoes.

    Science.gov (United States)

    Epelboin, Yanouk; Talaga, Stanislas; Epelboin, Loïc; Dusfour, Isabelle

    2017-11-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) that recently caused outbreaks in the Americas. Over the past 60 years, this virus has been observed circulating among African, Asian, and Pacific Island populations, but little attention has been paid by the scientific community until the discovery that large-scale urban ZIKV outbreaks were associated with neurological complications such as microcephaly and several other neurological malformations in fetuses and newborns. This paper is a systematic review intended to list all mosquito species studied for ZIKV infection or for their vector competence. We discuss whether studies on ZIKV vectors have brought enough evidence to formally exclude other mosquitoes than Aedes species (and particularly Aedes aegypti) to be ZIKV vectors. From 1952 to August 15, 2017, ZIKV has been studied in 53 mosquito species, including 6 Anopheles, 26 Aedes, 11 Culex, 2 Lutzia, 3 Coquillettidia, 2 Mansonia, 2 Eretmapodites, and 1 Uranotaenia. Among those, ZIKV was isolated from 16 different Aedes species. The only species other than Aedes genus for which ZIKV was isolated were Anopheles coustani, Anopheles gambiae, Culex perfuscus, and Mansonia uniformis. Vector competence assays were performed on 22 different mosquito species, including 13 Aedes, 7 Culex, and 2 Anopheles species with, as a result, the discovery that A. aegypti and Aedes albopictus were competent for ZIKV, as well as some other Aedes species, and that there was a controversy surrounding Culex quinquefasciatus competence. Although Culex, Anopheles, and most of Aedes species were generally observed to be refractory to ZIKV infection, other potential vectors transmitting ZIKV should be explored.

  16. Zika virus: An updated review of competent or naturally infected mosquitoes

    Science.gov (United States)

    Talaga, Stanislas; Epelboin, Loïc; Dusfour, Isabelle

    2017-01-01

    Zika virus (ZIKV) is an arthropod-borne virus (arbovirus) that recently caused outbreaks in the Americas. Over the past 60 years, this virus has been observed circulating among African, Asian, and Pacific Island populations, but little attention has been paid by the scientific community until the discovery that large-scale urban ZIKV outbreaks were associated with neurological complications such as microcephaly and several other neurological malformations in fetuses and newborns. This paper is a systematic review intended to list all mosquito species studied for ZIKV infection or for their vector competence. We discuss whether studies on ZIKV vectors have brought enough evidence to formally exclude other mosquitoes than Aedes species (and particularly Aedes aegypti) to be ZIKV vectors. From 1952 to August 15, 2017, ZIKV has been studied in 53 mosquito species, including 6 Anopheles, 26 Aedes, 11 Culex, 2 Lutzia, 3 Coquillettidia, 2 Mansonia, 2 Eretmapodites, and 1 Uranotaenia. Among those, ZIKV was isolated from 16 different Aedes species. The only species other than Aedes genus for which ZIKV was isolated were Anopheles coustani, Anopheles gambiae, Culex perfuscus, and Mansonia uniformis. Vector competence assays were performed on 22 different mosquito species, including 13 Aedes, 7 Culex, and 2 Anopheles species with, as a result, the discovery that A. aegypti and Aedes albopictus were competent for ZIKV, as well as some other Aedes species, and that there was a controversy surrounding Culex quinquefasciatus competence. Although Culex, Anopheles, and most of Aedes species were generally observed to be refractory to ZIKV infection, other potential vectors transmitting ZIKV should be explored. PMID:29145400

  17. Taxonomic Study of Species Formerly Identified as Anopheles mediopunctatus and Resurrection of An. costai (Diptera: Culicidae)

    Science.gov (United States)

    1999-05-01

    Diptera: Culicidae). Rev. Bras. Entomol. 10: 169-187. 1962. Entomologia medica, vol. I. Parte Geral, Diptera, Anophelini. Faculdade de Higiene e...Ronderos. 1962. Mosquitos de la Re- Ortiz, I. 1968. Apuentes de entomologia medica: 10s mos- publica Argentina. I. Tribu Anophelini (Diptera - Culic

  18. RNA splicing in a new rhabdovirus from Culex mosquitoes.

    Science.gov (United States)

    Kuwata, Ryusei; Isawa, Haruhiko; Hoshino, Keita; Tsuda, Yoshio; Yanase, Tohru; Sasaki, Toshinori; Kobayashi, Mutsuo; Sawabe, Kyoko

    2011-07-01

    Among members of the order Mononegavirales, RNA splicing events have been found only in the family Bornaviridae. Here, we report that a new rhabdovirus isolated from the mosquito Culex tritaeniorhynchus replicates in the nuclei of infected cells and requires RNA splicing for viral mRNA maturation. The virus, designated Culex tritaeniorhynchus rhabdovirus (CTRV), shares a similar genome organization with other rhabdoviruses, except for the presence of a putative intron in the coding region for the L protein. Molecular phylogenetic studies indicated that CTRV belongs to the family Rhabdoviridae, but it is yet to be assigned a genus. Electron microscopic analysis revealed that the CTRV virion is extremely elongated, unlike virions of rhabdoviruses, which are generally bullet shaped. Northern hybridization confirmed that a large transcript (approximately 6,500 nucleotides [nt]) from the CTRV L gene was present in the infected cells. Strand-specific reverse transcription-PCR (RT-PCR) analyses identified the intron-exon boundaries and the 76-nt intron sequence, which contains the typical motif for eukaryotic spliceosomal intron-splice donor/acceptor sites (GU-AG), a predicted branch point, and a polypyrimidine tract. In situ hybridization exhibited that viral RNAs are primarily localized in the nucleus of infected cells, indicating that CTRV replicates in the nucleus and is allowed to utilize the host's nuclear splicing machinery. This is the first report of RNA splicing among the members of the family Rhabdoviridae.

  19. Diptera Community In The Littoral Zone Of A North East Arid Zone ...

    African Journals Online (AJOL)

    Maiduguri, Nigeria, were studied between January and June 2002. Dipteran samples were collected every 2 weeks from five different stations. Five groups of diptera organisms simulidae, chironomidae, centrapogo nidae, culicidae and chaoboridae were found in analyzable numbers. The diptera assemblage was ...

  20. Darker eggs of mosquitoes resist more to dry conditions: Melanin enhances serosal cuticle contribution in egg resistance to desiccation in Aedes, Anopheles and Culex vectors.

    Science.gov (United States)

    Farnesi, Luana C; Vargas, Helena C M; Valle, Denise; Rezende, Gustavo L

    2017-10-01

    Mosquito vectors lay their white eggs in the aquatic milieu. During early embryogenesis water passes freely through the transparent eggshell, which at this moment is composed of exochorion and endochorion. Within two hours the endochorion darkens via melanization but even so eggs shrink and perish if removed from moisture. However, during mid-embryogenesis, cells of the extraembryonic serosa secrete the serosal cuticle, localized right below the endochorion, becoming the third and innermost eggshell layer. Serosal cuticle formation greatly reduces water flow and allows egg survival outside the water. The degree of egg resistance to desiccation (ERD) at late embryogenesis varies among different species: Aedes aegypti, Anopheles aquasalis and Culex quinquefasciatus eggs can survive in a dry environment for ≥ 72, 24 and 5 hours, respectively. In some adult insects, darker-body individuals show greater resistance to desiccation than lighter ones. We asked if egg melanization enhances mosquito serosal cuticle-dependent ERD. Species with higher ERD at late embryogenesis exhibit more melanized eggshells. The melanization-ERD hypothesis was confirmed employing two Anopheles quadrimaculatus strains, the wild type and the mutant GORO, with a dark-brown and a golden eggshell, respectively. In all cases, serosal cuticle formation is fundamental for the establishment of an efficient ERD but egg viability outside the water is much higher in mosquitoes with darker eggshells than in those with lighter ones. The finding that pigmentation influences egg water balance is relevant to understand the evolutionary history of insect egg coloration. Since eggshell and adult cuticle pigmentation ensure insect survivorship in some cases, they should be considered regarding species fitness and novel approaches for vector or pest insects control.

  1. Local extinction of the Asian tiger mosquito (Aedes albopictus) following rat eradication on Palmyra Atol

    Science.gov (United States)

    Lafferty, Kevin D.; McLaughlin, John P.; Gruner, Daniel S.; Bogar, Taylor A.; Bui, An; Childress, Jasmine N.; Espinoza, Magaly; Forbes, Elizabeth S.; Johnston, Cora A.; Klope, Maggie; Kuile, Ana Miller-ter; Lee, Michelle; Plummer, Katherine A.; Weber, David A.; Young, Ronald T.; Young, Hillary S.

    2018-01-01

    The Asian tiger mosquito, Aedes albopictus, appears to have been extirpated from Palmyra Atoll following rat eradication. Anecdotal biting reports, collection records, and regular captures in black-light traps showed the species was present before rat eradication. Since then, there have been no biting reports and no captures over 2 years of extensive trapping (black-light and scent traps). By contrast, the southern house mosquito, Culex quinquefasciatus, was abundant before and after rat eradication. We hypothesize that mammals were a substantial and preferred blood meal for Aedes, whereas Culex feeds mostly on seabirds. Therefore, after rat eradication, humans and seabirds alone could not support positive population growth or maintenance of Aedes. This seems to be the first documented accidental secondary extinction of a mosquito. Furthermore, it suggests that preferred host abundance can limit mosquito populations, opening new directions for controlling important disease vectors that depend on introduced species like rats.

  2. [Record of epidemiologically important Culicidae in the rural area of Manaus, Amazonas].

    Science.gov (United States)

    Barbosa, Maria das Graças Vale; Fé, Nelson Ferreira; Marcião, Alexandre Herculano Ribera; Silva, Ana Paula Thomé da; Monteiro, Wuelton Marcelo; Guerra, Marcus Vinitius de Farias; Guerra, Jorge Augusto de Oliveira

    2008-01-01

    The biodiversity of the Amazon region includes many species of arthropod vectors in different ecotopes, thus enabling occurrences of diseases like malaria, filariasis and arbovirosis. From August 2001 to July 2002, we gathered culicids from inside homes, from areas surrounding these homes and from forested areas of the São João Community, in the rural zone of Manaus, State of Amazonas. 1240 specimens were collected, belonging to the Culicinae (99%) and Anophelinae (1%) subfamilies, with 50 species. The Culicini tribe clearly predominated, with 904 specimens (72.9%), and the species Culex usquatus (22.6%) and Culex quinquefasciatus (17.7%) were prominent. Out of the total number of culicids, 1,077 (86.9%) were caught in the forests, 101 (8.1%) in the areas surrounding homes and 62 (5%) inside homes. Forests were the ecotope that presented the highest species diversity. The presence of Anopheles darlingi, Anopheles triannulatus, Aedes aegypti, Haemagogus janthinomys and other proven or potential vectors was recorded.

  3. Laboratory Evaluations of the Fractions Efficacy of Annona senegalensis (Annonaceae) Leaf Extract on Immature Stage Development of Malarial and Filarial Mosquito Vectors.

    Science.gov (United States)

    Lame, Younoussa; Nukenine, Elias Nchiwan; Pierre, Danga Yinyang Simon; Elijah, Ajaegbu Eze; Esimone, Charles Okechukwu

    2015-12-01

    Within the framework to control mosquitoes, ovicidal, larvicidal and pupicidal activity of Annona senegalensis leaf extract and its 4 fractions against Anopheles gambiae and Culex quinquefasciatus were evaluated in the laboratory conditions. Ovicidal test was performed by submitting at least 100 eggs of mosquitoes to 125, 250, 500, 1000 and 2000 ppm concentrations, while larvicidal and pupicidal effects were assessed by submitting 25 larvae or pupae to the concentrations of 2500, 1250, 625 and 312.5 ppm of plant extract or fractions of A. senegalensis. The eggs of An. gambiae were most affected by N-hexane (0.00% hatchability) and chloroform (03.67% hatchability) fractions compared to Cx. quinquefasciatus where at least 25 % hatchability were recorded at 2000 ppm. For larvicidal test, N-hexane (LC50= 298.8 ppm) and chloroform (LC50= 418.3 ppm) fractions were more effective than other fractions on An. gambiae larvae while, a moderate effectiveness was also observed with N-hexane (LC50= 2087.6 ppm), chloroform (LC50= 9010.1 ppm) fractions on Cx. quinquefasciatus larvae. The highest mortality percent of the pupae were also recorded with N-hexane and chloroform fractions on An. gambiae at 2500 ppm. As for Cx. quinquefasciatus only 50 % and 36 % mortality were recorded with N-hexane and chloroform fractions respectively. The extract of A. senegalensis was toxic on immature stage of mosquito species tested. By splitting methanolic crude extract, only N-hexane and chloroform fractions were revealed to possess a mosquitocidal effects and could be considered and utilized for future immature mosquito vectors control.

  4. Laboratory Evaluations of the Fractions Efficacy of Annona senegalensis (Annonaceae Leaf Extract on Immature Stage Development of Malarial and Filarial Mosquito Vectors

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    Younoussa Lame

    2015-10-01

    Full Text Available Background: Within the framework to control mosquitoes, ovicidal, larvicidal and pupicidal activity of Annona senegalensis leaf extract and its 4 fractions against Anopheles gambiae and Culex quinquefasciatus were evaluated in the laboratory conditions.Methods: Ovicidal test was performed by submitting at least 100 eggs of mosquitoes to 125, 250, 500, 1000 and 2000 ppm concentrations, while larvicidal and pupicidal effects were assessed by submitting 25 larvae or pupae to the concentrations of 2500, 1250, 625 and 312.5 ppm of plant extract or fractions of A. senegalensis.Results: The eggs of An. gambiae were most affected by N-hexane (0.00% hatchability and chloroform (03.67% hatchability fractions compared to Cx. quinquefasciatus where at least 25 % hatchability were recorded at 2000 ppm. For larvicidal test, N-hexane (LC50= 298.8 ppm and chloroform (LC50= 418.3 ppm fractions were more effective than other fractions on An. gambiae larvae while, a moderate effectiveness was also observed with Nhexane (LC50= 2087.6 ppm, chloroform (LC50= 9010.1 ppm fractions on Cx. quinquefasciatus larvae. The highest mortality percent of the pupae were also recorded with N-hexane and chloroform fractions on An. gambiae at 2500 ppm. As for Cx. quinquefasciatus only 50 % and 36 % mortality were recorded with N-hexane and chloroform fractions respectively.Conclusion: The extract of A. senegalensis was toxic on immature stage of mosquito species tested. By splitting methanolic crude extract, only N-hexane and chloroform fractions were revealed to possess a mosquitocidal effects and could be considered and utilized for future immature mosquito vectors control.

  5. Phytosanitary treatments against Bactrocera dorsalis(Diptera: Tephritidae): current situation and future prospects

    Science.gov (United States)

    Bactrocera dorsalis(Hendel)(Diptera: Tephritidae) is arguably the most important tephritid attacking fruits after Ceratitis capitata(Wiedemann)(Diptera: Tephritidae). In 2003, it was found in Africa and quickly spread to most of the sub-Saharan part of the continent destroying fruits and creating re...

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

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    Mário Luís Pessôa Guedes

    2014-03-01

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

  7. Structural characterization of acetylcholinesterase 1 from the sand fly Lutzomyia longipalpis (Diptera: Psychodidae).

    Science.gov (United States)

    Coutinho-Abreu, I V; Balbino, V Q; Valenzuela, J G; Sonoda, I V; Ramalho-Ortigão, J M

    2007-07-01

    Acetylcholinesterase (AChE) plays a key role in cholinergic impulse transmission, and it is the target enzyme for organophosphorus and carbamate insecticides. Two genes, AceI and AceII, have been characterized from different insect species, and point mutations in either gene can lead to significant resistance to these classes of insecticides. In this report, we describe the partial characterization of the AceI gene from Lutzomyia longipalpis (Lutz & Neiva) (Diptera: Psychodidae), and we show that the possibility exists for the development of a resistant phenotype to organophosphates and carbamates in sand flies. Our results point to the presence of a single AceI gene in L. longipalpis (LlAce1) and that AChE activity is inhibited by organophosphorus at a concentration of 5 x 10(-5) M. Regarding insecticide resistance, analysis of the truncated LlAce1 cDNA suggests that a single missense mutation leading to a glycine-to-serine substitution at amino acid position 119 (G119S) may arise in L. longipalpis, similar to what has been detected in Anopheles gambiae s.s. Another missense mutation involved in resistant phenotypes, F331W, detected in Culex tritaeniorhynchus Giles, is less likely to occur in L. longipalpis, because it faces codon constraint in this sand fly species. Comparison of the three-dimensional structures of the deduced amino acid sequence of the truncated LLAChE1 with that of An. gambiae and Cx. tritaeniorhynchus also suggests that similar structural modifications due to the missense amino acid changes in the active site gorge are detected in all three insects.

  8. Avian phenotypic traits related to feeding preferences in two Culex mosquitoes

    Science.gov (United States)

    Yan, Jiayue; Gangoso, Laura; Martínez-de la Puente, Josué; Soriguer, Ramón; Figuerola, Jordi

    2017-10-01

    Host choice by mosquitoes affects the transmission dynamics of vector-borne infectious diseases. Although asymmetries in mosquito attraction to vertebrate species have been reported, the relative importance of host characteristics in mosquito blood-feeding behavior is still poorly studied. Here, we investigate the relationship between avian phenotypic traits—in particular, morphometry, plumage coloration, and nesting and roosting behavior—and the blood-feeding patterns in two common Culex mosquito species on a North American avian community. Forage ratios of the mosquito species were unrelated to the phylogenetic relationships among bird species. Culex pipiens fed preferably on birds with lighter-colored plumage and longer tarsi; furthermore, solitary roosting avian species were both bitten by Cx. pipiens and Cx. restuans more often than expected. These associations may be explained by greater mosquito attraction towards larger birds with a greater color contrast against the background. Although communally roosting birds may release more cues and attract more mosquitoes, individuals may in fact receive fewer bites due to the encounter-dilution effect. Mosquito feeding behavior is a highly complex phenomenon, and our results may improve understanding of the non-random interaction between birds and mosquitoes in natural communities.

  9. Species composition, co-occurrence, association and affinity indices of mosquito larvae (Diptera: Culicidae) in Mazandaran Province, northern Iran.

    Science.gov (United States)

    Nikookar, Seyed Hassan; Azari-Hamidian, Shahyad; Fazeli-Dinan, Mahmoud; Nasab, Seyed Nouraddin Mousavi; Aarabi, Mohsen; Ziapour, Seyyed Payman; Enayati, Ahmadali

    2016-05-01

    Although considerable progress has been made in the past years in management of mosquito borne diseases such as malaria, dengue, yellow fever and West Nile fever through research in biology and ecology of the vectors, these diseases are still major threats to human health. Therefore, more research is required for better management of the diseases. This investigation provides information on the composition, co-occurrence, association and affinity indices of mosquito larvae in Mazandaran Province, northern Iran. In a large scale field study, mosquito larvae were collected from 120 sentinel sites in 16 counties in Mazandaran Province, using standard 350 ml dipper. Sampling took place monthly from May to December 2014. Collected larvae were mounted on glass slides using de Faure's medium and were diagnosed using morphological characters. Totally, 19,840 larvae were collected including three genera and 16 species from 120 larval habitats, as follows: Anopheles claviger, Anopheles hyrcanus, Anopheles maculipennis s.l., Anopheles marteri, Anopheles plumbeus, Anopheles pseudopictus, Culex pipiens, Culex tritaeniorhynchus, Culex torrentium, Culex perexiguus, Culex territans, Culex mimeticus, Culex hortensis, Culiseta annulata, Culiseta longiareolata, and Culiseta morsitans. Predominant species were Cx. pipiens and An. maculipennis s.l. which show the highest co-occurrence. The pair of species An. hyrcanus/An. pseudopictus showed significant affinity and association. High co-occurrence of the predominant species Cx. pipiens and An. maculipennis s.l. in the study area is of considerable importance in terms of vector ecology. It was also revealed that An. pseudopictus/An. hyrcanus often occur sympatrically indicating their common habitat requirements. The information may be equally important when vector control measures are considered. Copyright © 2016 Elsevier B.V. All rights reserved.

  10. Field trial on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes in shelters without walls (beruga) in Lombok, Indonesia.

    Science.gov (United States)

    Kawada, Hitoshi; Maekawa, Yoshihide; Takagi, Masahiro

    2005-12-01

    Field trials on the spatial repellency of metofluthrin-impregnated plastic strips for mosquitoes present in shelters without walls (beruga) were carried out in Lombok, Indonesia. A major reduction in the incidence of human biting by Culex quinquefasciatus was achieved, and the use of two strips per beruga repelled >60% of the mosquitoes for at least 11 wk while four strips repelled >60% of the mosquitoes for more than 15 weeks. The technique was found to be a practical long-term solution for the prevention of mosquito bites without using electricity or heat to evaporate the metofluthrin.

  11. Fauna of mosquito larvae (Diptera: Culicida) in Asir Provence, Kingdom of Saudi Arabia.

    Science.gov (United States)

    Al Ashry, Hamdy A; Kenawy, Mohamed A; Shobrak, Mohammed

    2014-04-01

    An entomological survey was undertaken for one year to update the mosquito fauna of Asir Region, Kingdom of Saudi Arabia. A total of 31 species of 8 genera were reported of which genus Culex (55%) was the most common. Most of collected larvae (59%) belonged to genus Culex (+ Lutzia) followed by Culiseta (26%), Anopheles (13%) and Aedine spp. (2%). Cx. pipiens (39%) and Cs. longiareolata (26.%) were generally the most abundant of all collected larvae. Of the Anopheles spp., An. dthali was common (40%), of Culex spp., Cx. pipiens was predominating (66%) and of Aedine spp., St. aegypti was predominating (71%). Four species: An. fluviatilis, Cx. mattinglyi, Cx. arbieeni and Cx. mimeticus were new reports in Asir Region and Cx. wigglesworthi recorded for the first time from the kingdom. Larvae were more common in low- and highlands than in the moderately altitude areas. In general all species prefer stagnant water but with the exception of Aedine larvae (altogether), the other species prefer presence of algae, vegetation and shade and absence of turbidity (except Culex spp.). A total of 98 different forms of association were reported of which 9 forms were common. All genera breed year round with peaks of abundance during spring for Anopheles spp. and Culex spp. and during winter for Aedine spp. and Cs. longiareolata. A complete list of mosquito fauna of Asir Region comprising 45 spp. was presented based on the present and previous surveys. The study concluded that the occurrence and prevalence of mosquito species mainly the disease vectors in Asir carry the thread of maintaining and transmission of several mosquito-borne diseases.

  12. Host-feeding patterns of native Culex pipiens and invasive Aedes albopictus mosquitoes (Diptera: Culicidae) in urban zones from Barcelona, Spain.

    Science.gov (United States)

    Muñnoz, Joaquin; Eritja, Roger; Alcaide, Miguel; Montalvo, Tomás; Soriguer, Ramón C; Figuerola, Jordi

    2011-07-01

    The feeding patterns of haematophagous arthropods are of major importance in the amplification and transmission of infectious disease agents to vertebrate hosts, including humans. The establishment of new vector populations in nonnative range might alter transmission networks. The Asian tiger mosquito Aedes albopictus (Skuse) represents an example of how an invasive species can alter the risk of viral transmission to humans. Blood meal molecular identification from two sympatric mosquito species (the invasive Ae. albopictus and the native Culex pipiens) was carried out by polymerase chain reaction-based methods. Samples were collected in Barcelona metropolitan area, Spain, from June to October 2009 as part of a monitoring-control program. Blood meals were identified to the species level in 30 Ae. albopictus and 43 Cx. pipiens. Ae. albopictus acquired blood exclusively from human hosts (100%), whereas Cx. pipiens fed on a diversity of avian and mammalian hosts, including 35.7% of blood meals from humans. Based on mosquito diet, our results suggest that the Ae. albopictus invasion in Spain might increase the risk of virus transmission to humans and could support local outbreaks of imported tropical viruses such as dengue and chikungunya. However, in the studied area, the presence of this invasive species would have a negligible effect on the transmission of zoonotic agents such as West Nile virus. However, Cx. pipiens could amplify and transmit West Nile virus, but avian contribution to its diet was lower than that reported in North America. Feeding patterns of these mosquito species may help to understand the flavivirus outbreaks recently reported in southwestern Europe.

  13. Interactions between the invasive Burmese python, Python bivittatus Kuhl, and the local mosquito community in Florida, USA.

    Science.gov (United States)

    Reeves, Lawrence E; Krysko, Kenneth L; Avery, Michael L; Gillett-Kaufman, Jennifer L; Kawahara, Akito Y; Connelly, C Roxanne; Kaufman, Phillip E

    2018-01-01

    The Burmese python, Python bivittatus Kuhl, is a well-established invasive species in the greater Everglades ecosystem of southern Florida, USA. Most research on its ecological impacts focuses on its role as a predator and its trophic interactions with native vertebrate species, particularly mammals. Beyond predation, there is little known about the ecological interactions between P. bivittatus and native faunal communities. It is likely that established populations of P. bivittatus in southern Florida serve as hosts for native mosquito communities. To test this concept, we used mitochondrial cytochrome c oxidase subunit I DNA barcoding to determine the hosts of blood fed mosquitoes collected at a research facility in northern Florida where captive P. bivittatus and Argentine black and white tegu, Salvator merianae (Duméril and Bibron), are maintained in outdoor enclosures, accessible to local mosquitoes. We recovered python DNA from the blood meals of three species of Culex mosquitoes: Culex erraticus (Dyar and Knab), Culex quinquefasciatus Say, and Culex pilosus (Dyar and Knab). Culex erraticus conclusively (P = 0.001; Fisher's Exact Test) took more blood meals from P. bivittatus than from any other available host. While the majority of mosquito blood meals in our sample were derived from P. bivittatus, only one was derived from S. merianae. These results demonstrate that local mosquitoes will feed on invasive P. bivittatus, a recently introduced host. If these interactions also occur in southern Florida, P. bivittatus may be involved in the transmission networks of mosquito-vectored pathogens. Our results also illustrate the potential of detecting the presence of P. bivittatus in the field through screening mosquito blood meals for their DNA.

  14. Interactions between the invasive Burmese python, Python bivittatus Kuhl, and the local mosquito community in Florida, USA.

    Directory of Open Access Journals (Sweden)

    Lawrence E Reeves

    Full Text Available The Burmese python, Python bivittatus Kuhl, is a well-established invasive species in the greater Everglades ecosystem of southern Florida, USA. Most research on its ecological impacts focuses on its role as a predator and its trophic interactions with native vertebrate species, particularly mammals. Beyond predation, there is little known about the ecological interactions between P. bivittatus and native faunal communities. It is likely that established populations of P. bivittatus in southern Florida serve as hosts for native mosquito communities. To test this concept, we used mitochondrial cytochrome c oxidase subunit I DNA barcoding to determine the hosts of blood fed mosquitoes collected at a research facility in northern Florida where captive P. bivittatus and Argentine black and white tegu, Salvator merianae (Duméril and Bibron, are maintained in outdoor enclosures, accessible to local mosquitoes. We recovered python DNA from the blood meals of three species of Culex mosquitoes: Culex erraticus (Dyar and Knab, Culex quinquefasciatus Say, and Culex pilosus (Dyar and Knab. Culex erraticus conclusively (P = 0.001; Fisher's Exact Test took more blood meals from P. bivittatus than from any other available host. While the majority of mosquito blood meals in our sample were derived from P. bivittatus, only one was derived from S. merianae. These results demonstrate that local mosquitoes will feed on invasive P. bivittatus, a recently introduced host. If these interactions also occur in southern Florida, P. bivittatus may be involved in the transmission networks of mosquito-vectored pathogens. Our results also illustrate the potential of detecting the presence of P. bivittatus in the field through screening mosquito blood meals for their DNA.

  15. Abundância de culicídeos em área metropolitana preservada e suas implicações epidemiológicas Culicidae mosquito abundance in a preserved metropolitan area and its epidemiological implications

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    Carmen Beatriz Taipe-Lagos

    2003-06-01

    Full Text Available OBJETIVO: Estudar a fauna de culicídeos adultos em uma área de reserva na periferia urbana para definir as espécies de interesse em saúde pública. MÉTODOS: O estudo foi realizado no Parque Ecológico do Tietê, localizado na periferia urbana da Grande São Paulo, Brasil. Realizaram-se coletas mensais em três locais e horários distintos, com o uso de aspiradores elétricos, armadilhas CDC e de Shannon no período de agosto de 1996 até março de 1998. O tratamento dos dados baseou-se na estimativa de freqüências e abundâncias. RESULTADOS: Coletaram-se 53.496 exemplares, tendo sido reconhecidas 25 espécies ou grupos genéricos. As espécies Ochlerotatus scapularis, Culex quinquefasciatus e Culex declarator foram as mais freqüentes e abundantes. CONCLUSÕES: As espécies mais freqüentes e abundantes têm demonstrado eficiência na transmissão de agentes patogênicos ao homem em outras regiões. Atenção deve ser dada a esses culicídeos, pois o o local investigado, ao lado de um complexo urbano, reúne condições favoráveis à disseminação de doenças por vetores.OBJECTIVE: To study the adult Culicidae fauna in a preserved area in urban outskirts for describing species of public health concern. METHODS: This study was developed in the Tietê Ecological Park located in the outskirt of the city of São Paulo, Brazil. Monthly collections were undertaken in three habitats at different times using electric aspirators and CDC and Shannon traps from August 1996 to March 1998. Data analysis was based on estimates of frequencies and abundance. RESULTS: Twenty-five species or generic groups were identified among 53,496 specimens collected. Ochlerotatus scapularis, Culex quinquefasciatus, and Culex declarator were the most frequent and abundant species. CONCLUSIONS: The most frequent and abundant species have been implicated in disease transmission to man in other regions. Attention must be given to these Culicidae since the study area is

  16. Effects of virus dose and extrinsic incubation temperature on vector competence of Culex nigripalpus (Diptera: Culicidae) for St. Louis encephalitis virus.

    Science.gov (United States)

    Richards, Stephanie L; Anderson, Sheri L; Lord, Cynthia C; Tabachnick, Walter J

    2012-11-01

    Culex nigripalpus Theobald is a primary vector of St. Louis encephalitis virus in the southeastern United States. Cx. nigripalpus females were fed blood containing a low (4.0 +/- 0.01 log10 plaque-forming unit equivalents (PFUeq) /ml) or high (4.7 +/- 0.1 log10 PFUeq/ml) St. Louis encephalitis virus dose and maintained at extrinsic incubation temperatures (EIT) of 25 or 28 degrees C for 12 d. Vector competence was measured via quantitative real-time reverse transcriptase polymerase chain reaction to estimate PFUeq using rates of infection, dissemination, and transmission. There were no differences in infection rates between the two EITs at either dose. The low dose had higher infection rates at both EITs. Dissemination rates were significantly higher at 28 degrees C compared with 25 degrees C at both doses. Virus transmission was observed (<7%) only at 28 degrees C for both doses. The virus titer in body tissues was greater at 28 degrees C compared with 25 degrees C at both doses. The difference between the EITs was greater at the low dose, resulting in a higher titer for the low dose than the high dose at 28 degrees C. Virus titers in leg tissues were greater in mosquitoes fed the high versus low dose, but were not influenced by EIT. Further investigations using a variety of environmental and biological factors would be useful in exploring the complexity of vector competence.

  17. PENGARUH VARIASI DOSIS LARUTAN BUAH BELIMBING WULUH (Averrhoa bilimbi L.TERHADAP MORTALITAS LARVA NYAMUK Culex sp. SEBAGAI SUMBER BELAJAR BIOLOGI PADA MATERI INSEKTA

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    Bagas Rasid Sidik

    2015-11-01

    Full Text Available Control of larvae of Culex sp. can be done with larvicides. Larvicides used in an attempt to reduce the population of larvae in a breeding place or for termination of the chain of mosquito breeding. Insect repellent effective to kill mosquitoes, but that has not been come mosquito larvae will develop into mosquitoes. Insect repellent made from synthetic chemicals if used excessively will cause adverse effects to humans such as respiratory disorders, digestive, and the environment. The purpose of this study was to determine (1 Whether or not the effect of giving a solution of fruit starfruit (Averrhoa bilimbi, L. against Culex sp. mosquito larvae mortality, (2 determine the most appropriate dosage on mortality of larvae of mosquito Culex sp., (3 Compile the results of the research as a high school biology class X LKPS semester two. This study uses the method of experiment, the draft design used was completely randomized design Variety (CRD with the control (P0 and 4 treatments, namely P1: a dose of1/99 ml, P2: dose2/98 ml, P3: dose3/97 ml, and P4: a dose4/96 ml with 6 replicates each, the number of larvae 150 animals. Larva l sampling and testing conducted at Flores Street No. 19 Ganjar Supreme 14/2 City Metro. The test was analyzed using one-way Anava non-parametric Kruskall-Wallis test. The results of the analysis are obtained as follows: (1 There is a very significant influence on the administration of a solution of fruit starfruit (Averrhoa bilimbi, L. against Culex mosquito larvae mortality due to the α sp 0.05,   at α 0.01 in Chi-square table, (2 the mortality of larvae of Culex for 24 consecutive hour sare from lowest to highest mortality percentage is P0=0%, P1=60%, P2=83.33%, 83.33% =P3, andP4=86,66%. Based on the results of research and discussion we concluded that: (1 There is the effect of star fruit solution on mortality of larvae of Culex sp mosquitoes, with coefficientH=17.73>Chi-square value of7.81at α level of 0.05, 11, 3

  18. Mosquitoes (Diptera: Culicidae) of the Lower Dyje River Basin (Podyjí) at the Czech–Austrian border

    Czech Academy of Sciences Publication Activity Database

    Šebesta, Oldřich; Gelbič, Ivan; Minář, Jan

    2012-01-01

    Roč. 7, č. 2 (2012), s. 288-298 ISSN 1895-104X R&D Projects: GA MŠk 2B08003 Institutional research plan: CEZ:AV0Z60930519; CEZ:AV0Z50070508 Keywords : Aedes vexans * Aedes sticticus * Culex modestus * Culex pipiens Subject RIV: EG - Zoology Impact factor: 0.818, year: 2012

  19. Larvicidal Activities of Indigenous Bacillus thuringiensis Isolates and Nematode Symbiotic Bacterial Toxins against the Mosquito Vector, Culex pipiens (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Ashraf M Ahmed

    2017-06-01

    Full Text Available Background: The incidence of mosquito-borne diseases and the resistance of mosquitoes to conventional pesticides have recently caused a panic to the authorities in the endemic countries. This study was conducted to identify native larvicidal biopesticides against Culex pipiens for utilization in the battle against mosquito-borne diseases.Methods: Larvicidal activities of new indigenous Bacillus thuringiensis isolates and crude toxin complexes (TCs of two nematode bacterial-symbionts, Photorhabdus luminescens akhurstii (HRM1 and Ph. luminescens akhurstii (HS1 that tested against Cx. pipiens. B. thuringiensis isolates were recovered from different environmental samples in Saudi Arabia, and the entomopathogenic nematodes, Heterorhabditis indica (HRM1 and He. sp (HS1 were iso­lated from Egypt. Larvicidal activities (LC50 and LC95 of the potentially active B. thuringiensis strains or TCs were then evaluated at 24 and 48h post-treatment.Results: Three B. thuringiensis isolates were almost as active as the reference B. thuringiensis israelensis (Bti-H14, and seven isolates were 1.6–5.4 times more toxic than Bti-H14. On the other hand, the TCs of the bacterial sym­bionts, HRM1 and HS1, showed promising larvicidal activities. HS1 showed LC50 of 2.54 folds that of HRM1 at 24h post-treatment. Moreover, histopathological examinations of the HS1-treated larvae showed deformations in midgut epithelial cells at 24h post-treatment.Conclusion: Synergistic activity and molecular characterization of these potentially active biocontrol agents are currently being investigated. These results may lead to the identification of eco-friend mosquito larvicidal product(s that could contribute to the battle against mosquito-borne diseases.

  20. Trypanosoma culicavium sp nov., an avian trypanosome transmitted by Culex mosquitoes

    Czech Academy of Sciences Publication Activity Database

    Votýpka, Jan; Szabová, J.; Rádrová, J.; Zídková, J.; Svobodová, M.

    2012-01-01

    Roč. 62, MAR (2012), s. 745-754 ISSN 1466-5026 R&D Projects: GA MŠk(CZ) LC06009; GA ČR GD206/09/H026 Institutional support: RVO:60077344 Keywords : ORNITHOMYIA-AVICULARIA * BITING MIDGES * RIBOSOMAL-RNA * BLACK FLIES * AVIUM * TRANSMISSION * KINETOPLASTIDA * PARASITE * DIPTERA * VECTOR Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.112, year: 2012

  1. Molecular Characterization of the Kamese Virus, an Unassigned Rhabdovirus, Isolated from Culex pruina in the Central African Republic.

    Science.gov (United States)

    Simo Tchetgna, Huguette Dorine; Nakoune, Emmanuel; Selekon, Benjamin; Gessain, Antoine; Manuguerra, Jean-Claude; Kazanji, Mirdad; Berthet, Nicolas

    2017-06-01

    Rhabdoviridae is one of the most diversified families of RNA viruses whose members infect a wide range of plants, animals, and arthropods. The members of this family are classified into 13 genera and >150 unassigned viruses. Here, we sequenced the complete genome of a rhabdovirus belonging to the Hart Park serogroup, the Kamese virus (KAMV), isolated in 1977 from Culex pruina in the Central African Republic. The genomic sequence showed an organization typical of rhabdoviruses with additional genes in the P-M and G-L intergenic regions, as already reported for the Hart Park serogroup. Our Kamese strain (ArB9074) had 98% and 78.8% nucleotide sequence similarity with the prototypes of the KAMV and Mossuril virus isolated in Uganda and Mozambique in two different Culex species, respectively. Moreover, the protein sequences had 98-100% amino acid similarity with the prototype of the KAMV, except for an additional gene (U3) that showed a divergence of 6%. These molecular data show that our strain of the KAMV is genetically close to the Culex annuliorus strain that was circulating in Uganda in 1967. However, this study suggests the need to improve our knowledge of the KAMV to better understand its behavior, its life cycle, and its potential reservoirs.

  2. First Record of Chrysomya rufifacies (Macquart) (Diptera, Calliphoridae) in Southeastern Brazil

    OpenAIRE

    Ribeiro, Antonia de Castro; UNIRIO; Cardoso, Debora; UESB; Lessa, Cláudia Soares dos Santos; UNIRIO; Moya-Borja, Gonzalo Efrain; UFRRJ; Aguiar, Valéria Magalhães; UNIRIO

    2013-01-01

    The present note reports the first record of Chrysomya rufifacies (Macquart) in Southeastern Brazil, in the municipality of Seropédica, Rio de Janeiro. The collecting was conducted with Diptera traps using fresh fish as bait. Primeiro Registro de Chrysomya rufifacies (Macquart) (Diptera, Calliphoridae) no Sudeste do Brasil Resumo. A presente nota relata o primeiro registro da espécie Chrysomya rufifacies (Macquart), no Sudeste do Brasil, no Município de Serop&...

  3. RNA Splicing in a New Rhabdovirus from Culex Mosquitoes▿†

    Science.gov (United States)

    Kuwata, Ryusei; Isawa, Haruhiko; Hoshino, Keita; Tsuda, Yoshio; Yanase, Tohru; Sasaki, Toshinori; Kobayashi, Mutsuo; Sawabe, Kyoko

    2011-01-01

    Among members of the order Mononegavirales, RNA splicing events have been found only in the family Bornaviridae. Here, we report that a new rhabdovirus isolated from the mosquito Culex tritaeniorhynchus replicates in the nuclei of infected cells and requires RNA splicing for viral mRNA maturation. The virus, designated Culex tritaeniorhynchus rhabdovirus (CTRV), shares a similar genome organization with other rhabdoviruses, except for the presence of a putative intron in the coding region for the L protein. Molecular phylogenetic studies indicated that CTRV belongs to the family Rhabdoviridae, but it is yet to be assigned a genus. Electron microscopic analysis revealed that the CTRV virion is extremely elongated, unlike virions of rhabdoviruses, which are generally bullet shaped. Northern hybridization confirmed that a large transcript (approximately 6,500 nucleotides [nt]) from the CTRV L gene was present in the infected cells. Strand-specific reverse transcription-PCR (RT-PCR) analyses identified the intron-exon boundaries and the 76-nt intron sequence, which contains the typical motif for eukaryotic spliceosomal intron-splice donor/acceptor sites (GU-AG), a predicted branch point, and a polypyrimidine tract. In situ hybridization exhibited that viral RNAs are primarily localized in the nucleus of infected cells, indicating that CTRV replicates in the nucleus and is allowed to utilize the host's nuclear splicing machinery. This is the first report of RNA splicing among the members of the family Rhabdoviridae. PMID:21507977

  4. Prevalence and distribution of pox-like lesions, avian malaria, and mosquito vectors in Kipahulu valley, Haleakala National Park, Hawai'i, USA

    Science.gov (United States)

    Aruch, Samuel; Atkinson, Carter T.; Savage, Amy F.; LaPointe, Dennis

    2007-01-01

    We determined prevalence and altitudinal distribution of introduced avian malarial infections (Plasmodium relictum) and pox-like lesions (Avipoxvirus) in forest birds from Kīpahulu Valley, Haleakalā National Park, on the island of Maui, and we identified primary larval habitat for the mosquito vector of this disease. This intensively managed wilderness area and scientific reserve is one of the most pristine areas of native forest remaining in the state of Hawai‘i, and it will become increasingly important as a site for restoration and recovery of endangered forest birds. Overall prevalence of malarial infections in the valley was 8% (11/133) in native species and 4% (4/101) in nonnative passerines; prevalence was lower than reported for comparable elevations and habitats elsewhere in the state. Infections occurred primarily in ‘Apapane (Himatione sanguinea) and Hawai‘i ‘Amakihi (Hemignathus virens) at elevations below 1,400 m. Pox-like lesions were detected in only two Hawai‘i ‘Amakihi (2%; 2/94) at elevations below 950 m. We did not detect malaria or pox in birds caught at 1,400 m in upper reaches of the valley. Adult mosquitoes (Culex quinquefasciatus) were captured at four sites at elevations of 640, 760, 915, and 975 m, respectively. Culex quinquefasciatus larvae were found only in rock holes along intermittent tributaries of the two largest streams in the valley, but not in standing surface water, pig wallows, ground pools, tree cavities, and tree fern cavities. Mosquito populations in the valley are low, and they are probably influenced by periods of high rainfall that flush stream systems.

  5. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina Main breeding-containers for Aedes aegypti and associated culicids, Argentina

    Directory of Open Access Journals (Sweden)

    Marina Stein

    2002-10-01

    Full Text Available Se identificaron criaderos de Aedes (Stegomyia aegypti en dos ciudades de la provincia del Chaco (Noreste de Argentina: Presidencia Roque Saenz Peña y Machagai. Los recipientes encontrados en los patios de las viviendas capaces de colectar agua se clasificaron según tipo y tamaño, se contaron y examinaron. Aedes aegypti y Culex quinquefasciatus fueron las especies mas abundantes, encontrándose además Cx. maxi, Cx. saltanensis y Ochlerotatus scapularis. Los neumáticos y cajas de baterías para autos fueron los recipientes que más aportaron a la producción de formas inmaduras de los culícidos colectados. Las lluvias fueron un factor importante para la proliferacion de Ae. aegypti, así como también el habito comun en la población de guardar recipientes en sus casas que permitan el desarrollo de estos culícidos.Breeding containers for Aedes (Stegomyia aegypti were identified in two cities of Chaco Province (northeast Argentina: Presidencia Roque Saenz Peña and Machagai. All water-retaining recipients found in house backyards capable to retain water were classified according to their type and size, counted and checked. Aedes aegypti and Culex quinquefasciatus were the most frequently collected species, being also found Cx. maxi, Cx. saltanensis and Ochlerotatus scapularis. Tires and car batteries represented the most important type of container where immature forms of culicids could be found. Rain was an important factor for Ae. aegypti proliferation, as well as the widespread habit of the population of keeping useless containers at home, which allows the development of culicids.

  6. Molecular phylogeny of Miltogramminae (Diptera Sarcophagidae)

    DEFF Research Database (Denmark)

    Piwczyński, Marcin; Pape, Thomas; Deja-Sikora, Edyta

    2017-01-01

    Miltogramminae is one of the phylogenetically most poorly studied taxa of the species-rich family Sarcophagidae (Diptera). Most species are kleptoparasites in nests of solitary aculeate wasps and bees, although parasitoids and saprophagous species are also known, and the ancestral miltogrammine l...

  7. [Twenty-year surveillance of insects relevant to public health during the construction of hydroelectric facilities in Antioquia, Colombia].

    Science.gov (United States)

    Zuluaga, Walter Alonso; López, Yolanda Lucía; Osorio, Lisardo; Salazar, Luis Fernando; González, Marta Claudia; Ríos, Claudia María; Wolff, Marta Isabel; Escobar, José Pablo

    2012-09-01

    Entomological studies conducted in large hydroelectric infrastructure projects are a tool for the prevention and control of vector-borne diseases. These diseases emerge as a consequence of changes made to the terrain that often increase the natural and artificial mosquito larval habitats. Many of these insects are of public health importance and population increases result in an increased risk of disease transmission. The culicine (mosquito) and phlebotomine (sand fly) populations were characterized in the area of the Porce II and Porce III hydroelectric projects of Antioquia between 1990 to 2009. Periodical entomological samplings were made in the area of impact, in the workers camps, and construction sites. Adult specimens were captured with nets, Shannon light traps, CDC light traps, and protected human bait. Mosquito larvae of the following species were identified: Culex coronator, Culex nigripalpus, Culex corniger, Culex quinquefasciatus and Limatus durhami. The most frequently identifiers of larval habitats were low tanks, waste cans, tires, and aquatic plants. Aedes aegypti specimens were captured in only two rural locations from two municipalities within the area of influence. Specimens from the following mosquito genera were captured in forest areas: Aedes, Mansonia, Culex, Psorophora, Wyeomyia, Phonyomyia, Uranotaenia, Haemagogus and Sabethes. The most important mosquito found was Haemogogus janthinomis, an efficient yellow fever vector in Colombia. The area has been endemic for leishmaniasis and in the current study, 20 species of Lutzomyia sand flies, potential vectors, were identified. Among malaria vectors, the most important species found in the area were Anopheles nuneztovari and Anopheles pseudopunctipennis. A wide variety of vectors were discovered in the area of the Porce II and Porce III hydroelectric projects, and many of these were relevant for public health. Further monitoring will be necessary to minimize disease transmission risks among the

  8. Limited impacts of truck-based ultra-low-volume applications of mosquito adulticides on mortality in honey bees (Apis mellifera).

    Science.gov (United States)

    Rinkevich, F D; Margotta, J W; Pokhrel, V; Walker, T W; Vaeth, R H; Hoffman, W C; Fritz, B K; Danka, R G; Rinderer, T E; Aldridge, R L; Linthicum, K J; Ottea, J A; Healy, K B

    2017-12-01

    Adulticides applied against mosquitoes can reduce vector populations during times of high arbovirus transmission. However, impacts of these insecticides on pollinators and other non-target organisms are of concern to mosquito control professionals, beekeepers and others. We evaluated mortality of Culex quinquefasciatus and Apis mellifera when caged insects were exposed to low and high label rates of four common adulticides (Aqua-Pursuit™ [permethrin], Duet® [prallethrin + sumithrin], Fyfanon® [malathion] and Scourge® [resmethrin]) at six distances up to 91.4 m from a truck-mounted ultra-low-volume sprayer. Honey bee mortality was both absolutely low (61 m had limited impacts on honey bee mortality while providing effective mosquito control.

  9. Juvenile i`iwi detected in lower elevations of Hawaii Volcanoes National Park

    Science.gov (United States)

    Gaudioso, Jacqueline M.; Beck, Angela T.

    2013-01-01

    The Hawaiian islands are home to a diverse array of plants and animals found nowhere else on Earth. Among the most famous of these are the spectacular Hawaiian honeycreepers, a group that evolved from a single flock of ancestral finches into at least 54 unique species. Unfortunately, the same isolation that fostered such dramatic adaptive radiation left Hawaiian species vulnerable. Under the onslaught of alien species predation and competition, habitat degradation, and introduced infectious diseases and parasites, most of the surviving honeycreepers have become largely confined to higher elevations. Intact habitat exists above the warm-weather range of deadly introduced avian malaria (Plasmodium relictum), and its mosquito vector (Culex quinquefasciatus).

  10. Bromeliad-associated mosquitoes from Atlantic forest in Santa Catarina Island, southern Brazil (Diptera, Culicidae, with new records for the State of Santa Catarina Mosquitos associados a bromélias em Mata Atlântica na Ilha de Santa Catarina, sul do Brasil (Diptera, Culicidae, com novos registros para o Estado de Santa Catarina

    Directory of Open Access Journals (Sweden)

    Gerson Azulim Müller

    Full Text Available Bromeliad-associated mosquitoes (Diptera: Culicidae in Atlantic Forest in Florianópolis, Santa Catarina, southern Brazil, were studied, examining plants of Vriesea philippocoburgi Wawra and Aechmea lindenii (E. Morren Baker var. lindenii at secondary Atlantic rain forest, and A. lindenii and Vriesea friburgensis Mez var. paludosa (L. B. Smith at "restinga" per month, during 12 months. No immature forms of mosquitoes were collected from A. lindenii in the secondary forest. Collections obtained 368 immature mosquitoes, none of them from A. lindenii from rain forest. Culex (Microculex spp. constituted 79.8% of the total, Wyeomyia (Phoniomyia spp. 17.93%, and Anopheles (Kerteszia cruzii (Dyar & Knab, 1908 only 1.36%. The study shows the great predominance of species of medical importance not yet proved, and the small number of immature stages of anopheline mosquitoes. The rainfall, but not the mean temperatures, significantly influenced the quantity of mosquitoes from V. philippocoburgi. Significant differences between the quantities of immature forms of all the bromeliad species were found, and the shape of the plants could be important to the abundance of mosquitoes. All six species of Cx. (Microculex found are recorded for the first time in the State of Santa Catarina, and all six species of Wyeomyia (Phoniomyia are recorded for the first time in bromeliads in this state.Mosquitos (Diptera: Culicidae associados a bromélias em Mata Atlântica na Ilha de Santa Catarina, no Estado de Santa Catarina, foram estudados. Foram examinadas mensalmente plantas de Vriesea philippocoburgi Wawra e Aechmea lindenii (E. Morren Baker var. lindenii de floresta atlântica pluvial ombrófila e A. lindenii e Vriesea friburgensis Mez var. paludosa (L. B. Smith de restinga, durante 12 meses. As coletas resultaram em 368 formas imaturas de mosquitos, sendo que nenhuma foi coletada em A. lindenii de mata ombrófila. Culex (Microculex spp. constituíram 79,8% do total

  11. First report of L1014F-kdr mutation in Culex pipiens complex from Morocco.

    Science.gov (United States)

    Bkhache, Meriem; Tmimi, Fatim-Zohra; Charafeddine, Omar; Faraj, Chafika; Failloux, Anna-Bella; Sarih, M'hammed

    2016-12-16

    Mosquitoes of the Culex pipiens complex, competent vectors for West Nile virus (WNV) and Rift Valley fever virus (RVFV) are widely targeted by insecticide treatments. The intensive application of chemical insecticides led to the development of resistance in many insects including Culex pipiens mosquitoes. The absence of data on resistance mechanisms in Morocco allow us to assess the levels of lambda-cyhalothrin resistance and the frequency of the mutated gene L1014F kdr in different forms of Cx. pipiens complex from three regions of Morocco. Mosquito adults were reared from immature stages collected in three different regions in Morocco (Tangier, Casablanca and Marrakech). Standard WHO insecticide susceptibility tests were conducted on adults emerged from collected larvae. Specimens were identified as belonging to the Culex pipiens complex using a multiplex PCR assay with diagnostic primers designed from the flanking region of microsatellite CQ11. Identified mosquitoes were then tested for the presence of the L1014F kdr mutation using PCR assay. Our results showed that 21% of the tested population has a resistance to lambda-cyhalothrin. The molecular identification of survivors shows that 43% belonged to the Cx. pipiens pipiens and only 9.5% to the Cx. pipiens molestus form. On the other hand, 416 specimens were screened for the L1014F kdr mutation. L1014F mutation was detected in different forms of Cx. pipiens in different sites. The frequency of L1014F mutation was similar between the Cx. pipiens pipiens form and hybrid form, while it was lower in the Cx. pipiens molestus form. The presence of the L1014F kdr allele was significantly associated with resistance to lambda-cyhalothrin in Cx. pipiens pipiens (P Morocco. These findings will provide important information to propose more adapted vector control measures towards this mosquito species, potential vector of arboviruses.

  12. Operational Evaluation Of Vectomax® WSP (Bacillus thuringiensis Subsp. israelensis+Bacillus sphaericus) Against Larval Culex pipiens in Septic Tanks (1).

    Science.gov (United States)

    Cetin, Huseyin; Oz, Emre; Yanikoglu, Atila; Cilek, James E

    2015-06-01

    The residual effectiveness of VectoMax® WSP (a water-soluble pouch formulation containing a combination of Bacillus thuringiensis subsp. israelensis strain AM65-52 and B. sphaericus strain ABTS 1743) when applied to septic tanks against 3rd- and 4th-stage larvae of Culex pipiens L. was evaluated in this study. This formulation was evaluated at operational application rates of 1 pouch (10 g) and 2 pouches (20 g) per septic tank. Both application rates resulted in >96% control of larvae for 24 days. Operationally, VectoMax WSP has proven to be a useful tool for the nonchemical control of Culex species in septic tank environments.

  13. Is the expression of autogeny by Culex molestus Forskal (Diptera: Culicidae) influenced by larval nutrition or by adult mating, sugar feeding, or blood feeding?

    Science.gov (United States)

    Kassim, Nur Faeza A; Webb, Cameron E; Russell, Richard C

    2012-06-01

    Culex molestus Forskal is suspected to have been introduced into southern Australia during the 1940s. Investigations to determine factors influencing the expression of autogeny, the response of this mosquito to potential blood meals, and the subsequent influence on oviposition were undertaken. Immature mosquitoes raised at five feeding regimes had mortality rates, development rates, wing length, and autogenous egg raft size measured. All surviving female mosquitoes laid autogenous eggs but there was a significant difference between the mean number of eggs per raft. For mosquitoes raised at each of the feeding regimes, there was a significant linear relationship between the number of eggs per autogenous egg raft and wing length. Newly emerged mosquitoes were offered a blood meal (i.e., rodent) daily but no blood feeding occurred until the autogenous egg raft was laid. There was no statistical difference in the rate of autogenous oviposition or post-oviposition blood feeding between control or treatment groups. The results of this study indicate that Cx. molestus is perfectly adapted to subterranean habitats in close association with human habitation, but their preference to delay blood feeding until up to day 8 following emergence may reduce their relative importance as a vector of arboviruses. © 2012 The Society for Vector Ecology.

  14. Diversity of mosquitoes and larval breeding preference based on physico-chemical parameters in Western Ghats, Tamilnadu, India

    Directory of Open Access Journals (Sweden)

    Periyasamy Senthamarai Selvan

    2015-06-01

    Full Text Available Objective: To study the diversity and distribution of mosquitoes in Western Ghats of Coimbatore and Nilgiris District, Tamilnadu, India. Methods: Random collections were carried out during August-2013 to July-2014 in cesspits, animal footprints, rock holes, tree holes, drainages at study areas of Marudhamalai, Valparai, Mettupalayam in Coimbatore District and Dhottapeta, Coonoor, Gudalur in Nilgiris District of Tamilnadu, India by using suction tube and kerosene pump. Mosquitoes were identified by standard entomological procedures. Results: A total of 1 018 mosquitoes (larvae and pupae were collected from all over the study areas comprising 6 genera and 23 species. They are, Culex mimulus, Culex pseudovishnui, Culex quinquefasciatus, Culex vishnui, Culex khazani, Culex uniformis, Heizmannia chandi, Heizmannia grenii, Heizmannia indica, Oclerotatus anureostriatus, Oclerotatus albotaeniatis, Oclerotatus deccanus, Oclerotatus gubernatoris, Aedes aegypti, Aedes albopictus, Aedes edwardsi, Aedes krombeini, Toxorhynchites minimus, Toxorhynchites splendens, Anopheles aitkenii, Anopheles barbirostris, Anopheles culiciformis and Anopheles maculatus. ShannonWeaver diversity index, Margalef’s index of richness and Simpsons dominance index was also studied. From 6 sites, the highest mosquitoes were collected from Marudhamalai (309 and the least mosquitoes were collected in Mettupalayam (68. The study determined whether physicochemical characteristics differ between habitats with high and low presence of mosquito larvae. Based on Margalef’s index of richness (Dmg, the highest values were present in Mettupalayam (5.214 study area and the lowest in Marudhamalai (3.837. It can be concluded from Shanon-Weaver index of diversity that, the highest values were present in Mettupalayam (2.947 and the least value were in Gudalur (2.410 during the study period. Conclusions: In areas with reservoirs of disease, mosquito abundance information can help to identify the

  15. Effect of food on immature development, consumption rate, and relative growth rate of Toxorhynchites splendens (Diptera: Culicidae, a predator of container breeding mosquitoes

    Directory of Open Access Journals (Sweden)

    D Dominic Amalraj

    2005-12-01

    Full Text Available Food utilization by the larvae of Toxorhynchites splendens (Wiedemann was studied in the laboratory by offering larvae of Aedes aegypti Linnaeus, Anopheles stephensi (Liston, and Culex quinquefasciatus (Say. Quantitative analyses of data indicated that immature development was significantly faster with increase in food availability. The regression analysis showed that the degrees of the relationship between immature duration (Id and food availability were higher when offered early instars of prey (first and second instars than late instars. Consumption rate (Cr of the predator increased with increase in food availability and this relationship was highly significant when larvae of An. stephensi were offered as food. Consumption rate to food level decreased with increase in the age class of the prey. There was a significant negative correlation between Id and Cr. This aspect helps to increase population turnover of T. splendens in a shorter period when the prey is abundant. Conversely, the predator compensated the loss in daily food intake at low food level by extending Id thereby attains the minimum threshold pupal weight for adult emergence. There was an increase in the relative growth rate (RGR of the predator when An. stephensi was offered as prey and this was related to the high protein content of the prey per body weight. There was a positive correlation between Cr and RGR. This adaptive life characteristic strategy of this predator is useful for mass-rearing for large scale field release programmes in the control of container breeding mosquitoes is discussed.

  16. Field evaluation of the bio-efficacy of three pyrethroid based coils against wild populations of anthropophilic mosquitoes in Northern Tanzania

    Directory of Open Access Journals (Sweden)

    Shandala Msangi

    2010-01-01

    Full Text Available Aims: This study aims to assess the feeding inhibition and repellency effect of three brands of mosquito coils in experimental huts (East African design. Evaluated products were all pyrethroid-based mosquito coils - Kiboko; , Total; and Risasi; . Mosfly (0.1% D-allethrin was a positive control. Indoor resting behavior, feeding inhibition and induced exophily were measured as responses of burnt coil smoke in huts. Materials and methods: Resting mosquitoes were collected inside the huts, in window traps and verandah traps using mechanical aspirators. Identified to species level and sex. Results: A total of 1460 mosquitoes were collected, 58.9% (n=860 were Anopheles gambiae s.l while 41.1% (n=600 Culex quinquefasciatus. Indoor resting mosquitoes in all treated huts were significantly reduced than in negative control (DF=4, F=18.6, P < 0.001. Species found to rest indoors were not statistical different between the positive control (Mosfly coil and other three treated huts (DF=3, F=1.068, P=0.408. Cx.quinquefasciatus had significantly higher induced exophily in all treatments comparing to An.gambiae s.l (DF=1, F=5.34, P=0.050. Comparison between species (An.gambiae s.l and Cx. quinquefasciatus for the feeding inhibition among treated huts was not statistically significant (DF=1, F=0.062, P=0.810. Conclusion: Introduction of several personal protection measures will be ideal to supplement the existing gap in reducing the man vector contacts hence lowering the disease transmission.

  17. Acaricidal, pediculicidal and larvicidal activity of synthesized ZnO nanoparticles using Momordica charantia leaf extract against blood feeding parasites.

    Science.gov (United States)

    Gandhi, P Rajiv; Jayaseelan, C; Mary, R Regina; Mathivanan, D; Suseem, S R

    2017-10-01

    The aim of the present study was to evaluate the acaricidal, pediculicidal and larvicidal effect of synthesized zinc oxide nanoparticles (ZnO NPs) using Momordica charantia leaf extract against the larvae of Rhipicephalus (Boophilus) microplus, adult of Pediculus humanus capitis, and the larvae of Anopheles stephensi, Culex quinquefasciatus. The ZnO NPs were characterized by using UV, XRD, FTIR and SEM-EDX. The SEM image confirms that the synthesized nanoparticles were spherical in shape with a size of 21.32 nm. The results of GC-MS analysis indicates the presence of the major compound of Nonacosane (C 29 H 60 ) in the M. charantia leaf extract. Cattle tick, head lice and mosquito larvae were exposed to a varying concentrations of the synthesized ZnO NPs and M. charantia leaf extract for 24 h. Compared to the leaf aqueous extract, biosynthesized ZnO NPs showed higher toxicity against R. microplus, P. humanus capitis, An. stephensi, and Cx. Quinquefasciatus with the LC 50 values of 6.87, 14.38, 5.42, and 4.87 mg/L, respectively. The findings revealed that synthesized ZnO NPs possess excellent anti-parasitic activity. These results suggest that the green synthesized ZnO NPs has the potential to be used as an ideal ecofriendly approach for the control of R. microplus, P. humanus capitis and the mosquito larvae of An. Stephensi and Cx. quinquefasciatus. Copyright © 2017 Elsevier Inc. All rights reserved.

  18. Schools as Potential Risk Sites for Vector-Borne Disease Transmission: Mosquito Vectors in Rural Schools in Two Municipalities in Colombia.

    Science.gov (United States)

    Olano, Víctor Alberto; Matiz, María Inés; Lenhart, Audrey; Cabezas, Laura; Vargas, Sandra Lucía; Jaramillo, Juan Felipe; Sarmiento, Diana; Alexander, Neal; Stenström, Thor Axel; Overgaard, Hans J

    2015-09-01

    Dengue and other vector-borne diseases are of great public health importance in Colombia. Vector surveillance and control activities are often focused at the household level. Little is known about the importance of nonhousehold sites, including schools, in maintaining vector-borne disease transmission. The objectives of this paper were to determine the mosquito species composition in rural schools in 2 municipalities in Colombia and to assess the potential risk of vector-borne disease transmission in school settings. Entomological surveys were carried out in rural schools during the dry and rainy seasons of 2011. A total of 12 mosquito species were found: Aedes aegypti, Anopheles pseudopunctipennis, Culex coronator, Cx. quinquefasciatus, and Limatus durhamii in both immature and adult forms; Ae. fluviatilis, Cx. nigripalpus, Cx. corniger, and Psorophora ferox in immature forms only; and Ae. angustivittatus, Haemagogus equinus, and Trichoprosopon lampropus in adult forms only. The most common mosquito species was Cx. quinquefasciatus. Classrooms contained the greatest abundance of adult female Ae. aegypti and Cx. quinquefasciatus. The most common Ae. aegypti breeding sites were containers classified as "others" (e.g., cans), followed by containers used for water storage. A high level of Ae. aegypti infestation was found during the wet season. Our results suggest that rural schools are potentially important foci for the transmission of dengue and other mosquito-borne diseases. We propose that public health programs should be implemented in rural schools to prevent vector-borne diseases.

  19. Selected phenotypic features of BR91, a unique spirochaetal strainisolated from the Culex pipiens mosquito

    Czech Academy of Sciences Publication Activity Database

    Šikutová, Silvie; Buňková, L.; Krejčí, E.; Halouzka, Jiří; Sanogo, Y. O.; Rudolf, Ivo

    2014-01-01

    Roč. 169, 5-6 (2014), s. 348-352 ISSN 0944-5013 R&D Projects: GA ČR GA206/00/1234; GA ČR GA206/03/0726 Institutional support: RVO:68081766 Keywords : Spirochaete * Culex pipiens * Enzyme activity * SDS-PAGE * FAMEa Subject RIV: EE - Microbiology, Virology Impact factor: 2.561, year: 2014

  20. Clinodiplosis costai, uma nova espécie galhadora (Diptera, Cecidomyiidae associada com Paullinia weinmanniaefolia Mart (Sapindaceae Clinodiplosis costai, a new galler species (Diptera, Cecidomyiidae associated with Paullinia weinmanniaefolia Mart (Sapindaceae

    Directory of Open Access Journals (Sweden)

    Valéria C. Maia

    2005-09-01

    Full Text Available Clinodiplosis costai, uma nova espécie de Cecidomyiidae (Diptera que induz galhas em folhas jovens de Paullinia weinmanniaefolia é descrita (larva, macho e fêmea com base em material do Estado do Rio de Janeiro (Brasil.Clinodiplosis costai, a new species of Cecidomyiidae (Diptera that induces galls on young leaves of Paullinia weinmanniaefolia is described (larva, male and female based on material from Rio de Janeiro State (Brazil.

  1. Preferências alimentares de mosquitos Culicidae no Vale do Ribeira, São Paulo, Brasil Feeding preferences of Culicidae mosquitoes in the Ribeira Valley, S.Paulo State, Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1987-06-01

    Full Text Available São apresentados os resultados obtidos na identificação do sangue ingerido por culicídeos ingurgitados coletados em vários ambientes rurais de cinco localidades do Vale do Ribeira, Estado de São Paulo (Brasil. O maior rendimento, que representou a quase totalidade dos espécimens coletados, foi obtido mediante o emprego da aspiração e das redes manuais. Foi possível identificar a origem de 1.444 repastos sangüíneos. Os Aedes apresentaram predominância de positividade para mamíferos. Ae. scapularis mostrou preferência por hospedeiros de grande porte representados por bovinos e eqüinos. Ae. serratus alimentou-se também em aves. Com exceção da elevada antropofilia de Cx. quinquefasciatus, os demais representantes de Cx. (Culex revelaram-se apreciavelmente ornitófilos. Em conjunto, Cx. (Melanoconion mostrou o mais amplo espectro de hematofagia, que incluiu anfíbio, ave, mamíferos e réptil. Cx. ribeirensis e Cx. sacchettae apresentaram resultados que sugerem alguma preferência por mamíferos. A antropofilia distribuiu-se por várias espécies destacando-se Ae. scapularis, Cx. sacchettae e Cx. ribeirensis que a apresentaram nas coletas efetuadas no intradomicílio. A influência da densidade de hospedeiros no ambiente modificado fez-se sentir em relação à primeira dessas três espécies, para as quais as evidências obtidas sugerem que estejam evoluindo no sentido da domiciliação.Results of blood-meal identification for mosquitoes collected in 5 different Ribeira Valley (S.Paulo State, Brazil environments are presented. Precipitin tests identified the sources of 1444 blood-meals. Aedes mosquitoes fed chiefly on mammals. Ae. scapularis showed a preference for cattle and horses. Ae. serratus also obtained meals from avian hosts. Leaving aside the anthropophilic Cx.quinquefasciatus, the other Culex (Culex mosquitoes showed feeding pattern directed to avian hosts. On the whole Culex (Melanoconion showed a largely eclectic

  2. Redescription of the Holotype of Culex (Culex) Peus Speiser and Taxonomy of Culex (Culex) Stigmatosoma Dyar and Thriambus Dyar (Diptera: Culicidae)

    Science.gov (United States)

    1988-10-12

    Ver- teneuil, Brussels. 257 pp. + 5 pls. Forattini, 0. P. 1965. Entomologia Medica. 2” Vol- ume_ Editora da Universidade de Sao Paulo. 506 PP...Publica, Boletines T&r& cos, Serie A: Entomologia Medica y Parasitologia No. 1. 66 pp. Matheson, R. 1944. Handbook of the Mosquitoes of North America

  3. Actividad de picadura de Culex quinquefasciatus (SAY, 1863 en Bogotá, Colombia

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    Marco Andrés Rojas Mogollón

    2013-07-01

    Conclusión. Este comportamiento diferente posiblemente esté asociado a las condiciones microambientales, como luz y actividad minera de la zona durante las 24 horas del día, pero no se encontró que estuviera relacionado con la presencia o ausencia de lluvia

  4. Effect of ivermectin on the larvae of Anopheles gambiae and Culex quinquefasciatus

    DEFF Research Database (Denmark)

    Derua, Yahya A.; Malongo, Bernard B.; Simonsen, Paul E.

    2016-01-01

    . Methods: A total of 1800 laboratory reared mosquito larvae of each species were used in the bioassays. Twelve replicates were performed, each testing 6 concentrations of ivermectin (0.0, 0.001, 0.01, 0.1, 1.0 and 10.0 parts per million (ppm)) against third instar larvae of An. gambiae and Cx...

  5. Ultrastructural changes in the flight muscle mitochondria of adult male mosquito Culex Pipiens L I

    International Nuclear Information System (INIS)

    Abd Elmeguid, A.; Elmoursy, A.A.; Rouchdy, H.; Elzahraa, F.

    1995-01-01

    Ultrastructural differences between differentiating myoblasts of 1-day old pupae and 2-day old pupae and between well developed flight muscles in newly emerged 1-day old and 2-day old and ageing 21-day old adult male Culex Pipiens were studied. Ageing mosquitoes showed various signs of deterioration, vocalization, fusion and disorientation of cristae. 6 figs

  6. Infection dynamics of western equine encephalomyelitis virus (Togaviridae: Alphavirus) in four strains of Culex tarsalis (Diptera: Culicidae): an immunocytochemical study.

    Science.gov (United States)

    Oviedo, Marco V Neira; Romoser, William S; James, Calvin Bl; Mahmood, Farida; Reisen, William K

    2011-04-18

    BACKGROUND: Vector competence describes the efficiency with which vector arthropods become infected with and transmit pathogens and depends on interactions between pathogen and arthropod genetics as well as environmental factors. For arbovirus transmission, the female mosquito ingests viremic blood, the virus infects and replicates in midgut cells, escapes from the midgut, and disseminates to other tissues, including the salivary glands. Virus-laden saliva is then injected into a new host. For transmission to occur, the virus must overcome several "barriers", including barriers to midgut infection and/or escape and salivary infection and/or escape. By examining the spatial/temporal infection dynamics of Culex tarsalis strains infected with western equine encephalomyelitis virus (WEEV), we identified tissue tropisms and potential tissue barriers, and evaluated the effects of viral dose and time postingestion. METHODS: Using immunostained paraffin sections, WEEV antigens were tracked in four Cx. tarsalis strains: two recently colonized California field strains - Coachella Valley, Riverside County (COAV) and Kern National Wildlife Refuge (KNWR); and two laboratory strains selected for WEEV susceptibility (high viremia producer, HVP), and WEEV resistance (WR). RESULTS AND CONCLUSIONS: Tissues susceptible to WEEV infection included midgut epithelium, neural ganglia, trachea, chorionated eggs, and salivary glands. Neuroendocrine cells in the retrocerebral complex were occasionally infected, indicating the potential for behavioral effects. The HVP and COAV strains vigorously supported viral growth, whereas the WR and KNWR strains were less competent. Consistent with earlier studies, WEEV resistance appeared to be related to a dose-dependent midgut infection barrier, and a midgut escape barrier. The midgut escape barrier was not dependent upon the ingested viral dose. Consistent with midgut infection modulation, disseminated infections were less common in the WR and KNWR

  7. Screening of Bacillus thuringiensis strains effective against mosquitoes Prospecção de estirpes de Bacillus thuringiensis efetivas contra mosquitos

    Directory of Open Access Journals (Sweden)

    Rose Gomes Monnerat

    2005-02-01

    Full Text Available The objective of this work was to evaluate 210 Bacillus thuringiensis strains against Aedes aegypti and Culex quinquefasciatus larvae to select the most effective. These strains were isolated from different regions of Brazil and are stored in a Bacillus spp. collection at Embrapa Recursos Genéticos e Biotecnologia, Brasília, Brazil. The selected strains were characterized by morphological (microscopy, biochemical (SDS-PAGE 10% and molecular (PCR methods. Six B. thuringiensis strains were identified as mosquito-toxic after the selective bioassays. None of the strains produced the expected PCR products for detection of cry4, cry11 and cyt1A genes. These results indicate that the activity of mosquitocidal Brazilian strains are not related with Cry4, Cry11 or Cyt proteins, so they could be used as an alternative bioinsecticide against mosquitoes.Neste trabalho foram realizados testes de patogenicidade com 210 estirpes de Bacillus thuringiensis contra larvas de Aedes aegypti e Culex quinquefasciatus, a fim de se determinar as mais eficazes. Estas estirpes foram isoladas de diversas regiões do Brasil e estão armazenadas na coleção de Bacillus spp. da Embrapa Recursos Genéticos e Biotecnologia. As estirpes selecionadas foram caracterizadas por métodos morfológicos (microscopia, bioquímicos (SDS-PAGE 10% e moleculares (Reação em Cadeia da Polimerase. Foram selecionadas seis estirpes entomopatogênicas de Bacillus thuringiensis. Nenhuma das estirpes de Bacillus thuringiensis apresentou produtos de PCR esperados para a detecção dos genes cry4, cry11 e cyt1A. A patogenicidade das estirpes não está associada à presença das toxinas Cry4, Cry11 ou Cyt, assim, essas estirpes poderão ser utilizadas para a formatação de um bioinseticida alternativo contra mosquitos.

  8. Infection and transmission of Rift Valley fever viruses lacking the NSs and/or NSm genes in mosquitoes: potential role for NSm in mosquito infection.

    Directory of Open Access Journals (Sweden)

    Mary B Crabtree

    Full Text Available BACKGROUND: Rift Valley fever virus is an arthropod-borne human and animal pathogen responsible for large outbreaks of acute and febrile illness throughout Africa and the Arabian Peninsula. Reverse genetics technology has been used to develop deletion mutants of the virus that lack the NSs and/or NSm virulence genes and have been shown to be stable, immunogenic and protective against Rift Valley fever virus infection in animals. We assessed the potential for these deletion mutant viruses to infect and be transmitted by Aedes mosquitoes, which are the principal vectors for maintenance of the virus in nature and emergence of virus initiating disease outbreaks, and by Culex mosquitoes which are important amplification vectors. METHODOLOGY AND PRINCIPAL FINDINGS: Aedes aegypti and Culex quinquefasciatus mosquitoes were fed bloodmeals containing the deletion mutant viruses. Two weeks post-exposure mosquitoes were assayed for infection, dissemination, and transmission. In Ae. aegypti, infection and transmission rates of the NSs deletion virus were similar to wild type virus while dissemination rates were significantly reduced. Infection and dissemination rates for the NSm deletion virus were lower compared to wild type. Virus lacking both NSs and NSm failed to infect Ae. aegypti. In Cx. quinquefasciatus, infection rates for viruses lacking NSm or both NSs and NSm were lower than for wild type virus. CONCLUSIONS/SIGNIFICANCE: In both species, deletion of NSm or both NSs and NSm reduced the infection and transmission potential of the virus. Deletion of both NSs and NSm resulted in the highest level of attenuation of virus replication. Deletion of NSm alone was sufficient to nearly abolish infection in Aedes aegypti mosquitoes, indicating an important role for this protein. The double deleted viruses represent an ideal vaccine profile in terms of environmental containment due to lack of ability to efficiently infect and be transmitted by mosquitoes.

  9. Infection and transmission of Rift Valley fever viruses lacking the NSs and/or NSm genes in mosquitoes: potential role for NSm in mosquito infection.

    Science.gov (United States)

    Crabtree, Mary B; Kent Crockett, Rebekah J; Bird, Brian H; Nichol, Stuart T; Erickson, Bobbie Rae; Biggerstaff, Brad J; Horiuchi, Kalanthe; Miller, Barry R

    2012-01-01

    Rift Valley fever virus is an arthropod-borne human and animal pathogen responsible for large outbreaks of acute and febrile illness throughout Africa and the Arabian Peninsula. Reverse genetics technology has been used to develop deletion mutants of the virus that lack the NSs and/or NSm virulence genes and have been shown to be stable, immunogenic and protective against Rift Valley fever virus infection in animals. We assessed the potential for these deletion mutant viruses to infect and be transmitted by Aedes mosquitoes, which are the principal vectors for maintenance of the virus in nature and emergence of virus initiating disease outbreaks, and by Culex mosquitoes which are important amplification vectors. Aedes aegypti and Culex quinquefasciatus mosquitoes were fed bloodmeals containing the deletion mutant viruses. Two weeks post-exposure mosquitoes were assayed for infection, dissemination, and transmission. In Ae. aegypti, infection and transmission rates of the NSs deletion virus were similar to wild type virus while dissemination rates were significantly reduced. Infection and dissemination rates for the NSm deletion virus were lower compared to wild type. Virus lacking both NSs and NSm failed to infect Ae. aegypti. In Cx. quinquefasciatus, infection rates for viruses lacking NSm or both NSs and NSm were lower than for wild type virus. In both species, deletion of NSm or both NSs and NSm reduced the infection and transmission potential of the virus. Deletion of both NSs and NSm resulted in the highest level of attenuation of virus replication. Deletion of NSm alone was sufficient to nearly abolish infection in Aedes aegypti mosquitoes, indicating an important role for this protein. The double deleted viruses represent an ideal vaccine profile in terms of environmental containment due to lack of ability to efficiently infect and be transmitted by mosquitoes.

  10. New gall midges (Diptera, Cecidomyiidae) associated with Eugenia uniflora and Psidium cattleianum (Myrtaceae)

    OpenAIRE

    Maia, Valéria C; Nava, Dori E

    2011-01-01

    Two new species and a new genus of gall midges (Diptera, Cecidomyiidae) are described and illustrated. Both species induce leaf galls on Myrtaceae, the former on Eugenia uniflora and the latter on Psidium cattleianum. Duas novas espécies e um novo gênero de insetos galhadores (Diptera, Cecidomyiidae) são descritos e ilustrados. Ambas espécies induzem galhas foliares em Myrtaceae, a primeira em Eugenia uniflora e a segunda em Psidium cattleianum.

  11. 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.

  12. The efficacy of repellents against Aedes, Anopheles, Culex and Ixodes spp. - a literature review.

    Science.gov (United States)

    Lupi, Eleonora; Hatz, Christoph; Schlagenhauf, Patricia

    2013-01-01

    Travellers are confronted with a variety of vector-borne threats. Is one type of repellent effective against all biting vectors? The aim of this review is to examine the literature, up to December 31st, 2012, regarding repellent efficacy. We searched PubMed for relevant papers. Repellents of interest were DEET, Icaridin as well as other piperidine-derived products (SS220), Insect Repellent (IR) 3535 (ethyl-butylacetyl-amino-propionat, EBAAP) and plant-derived products, including Citriodora (para-menthane-3,8-diol). As vectors, we considered the mosquito species Anopheles, Aedes and Culex as well as the tick species Ixodes. We selected only studies evaluating the protective efficacy of repellents on human skin. We reviewed a total of 102 publications. Repellents were evaluated regarding complete protection time or as percentage efficacy [%] in a time interval. We found no standardized study for tick bite prevention. Regarding Aedes, DEET at concentration of 20% or more, showed the best efficacy providing up to 10 h protection. Citriodora repellency against this mosquito genus was lower compared to the other products. Also between subspecies a difference could be observed: Ae. aegypti proved more difficult to repel than Ae. Albopictus. Fewer studies have been conducted on mosquito species Anopheles and Culex. The repellency profile against Anopheles species was similar for the four principal repellents of interest, providing on average 4-10 h of protection. Culex mosquitoes are easier to repel and all four repellents provided good protection. Few studies have been conducted on the tick species Ixodes. According to our results, the longest protection against Ixodes scapularis was provided by repellents containing IR3535, while DEET and commercial products containing Icaridin or PMD showed a better response than IR3535 against Ixodes ricinus. Many plant-based repellents provide only short duration protection. Adding vanillin 5% to plant-based repellents and to DEET

  13. Nuevos registros y distribución de mosquitos de la Argentina (Diptera: Culicidae New records and distribution of mosquitoes from Argentina (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Gustavo C. Rossi

    2006-12-01

    Full Text Available Se presentan 21 nuevos registros de especies y se amplía la distribución de otras 12 especies de los géneros Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach y Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald. Se incluyen comentarios y cambios de estatus para especies de Howardina Theobald, Ochlerotatus y Lutzia (Theobald. Actualmente, en la Argentina se hallan presentes 226 especies distribuidas en 23 géneros.Twenty one new records and 12 new distributional records of species of the genus Anopheles Meigen, Coquillettidia Dyar, Culex L., Haemagogus Williston, Ochlerotatus Lynch Arribalzaga, Onirion Harbach & Peyton, Orthopodomyia Theobald, Psorophora Robineau-Desvoidy, Sabethes Robineau-Desvoidy, Stegomyia Theobald, Toxorhynchites Theobald are reported. Comments and changes in the status of species of Howardina Theobald, Ochelrotatus and Lutzia Theobald are included. Currently, in Argentina are present 226 species distributed in 23 genera.

  14. ISOLASI BACILLUS THURINGIENSIS DARI LARVA DAN PENGUJIAN PATOGENISITASNYA TERHADAP LARVA NYAMUK VEKTOR

    Directory of Open Access Journals (Sweden)

    Blondine Ch. P.

    2012-09-01

    Full Text Available A study to evaluate pathogenic organisms as cause of mosquito larvae death was conducted at Wonokerto and Pabelan villages, Salatiga Luar Kota subdistrict, Semarang regency in Central Java from May 1991 through December 1991. Bacterial isolation from dead larvae showed that 31 B. thuringicnsis isolates were obtained from 31 larvae samples collected from 2 location e.g Wonokerto village (3 samples, Pabelan village (28 samples. Nineteen isolates (61,3% showed a pathogenicity of more than 50% to third toward instar larvae of Aedes aegypti and Culex quinquefasciatus respectively 24 hours after exposure. This study shows the possible use of B. thuringiensis for biologic control of mosquitoes which can act as vectors for human diseases.

  15. Um novo gênero e espécie de Schizomyiina (Diptera, Cedidomyiidae associados com Piperaceae no Brasil A new genus and species of Schizomyiina (Diptera, Cecidomyiidae associated with Piperaceae from Brazil

    Directory of Open Access Journals (Sweden)

    Valéria Cid Maia

    Full Text Available Parametasphondylia piperis (Diptera, Cecidomyiidae, Asphondyliini, Schizomyiina, um novo gênero e espécie galhadora associada com Piper sp. (Piperaceae é descrita e ilustrada (larva, pupa, macho e fêmea com base em material obtido em Minas Gerais, Brasil.Parametasphondylia piperis (Diptera, Cecidomyiidae, Asphondyliini, Schizomyiina, a new gall maker genus and species associated with Piper sp. (Piperaceae is described and illustrated (larva, pupa, male and female based on material obtained from Minas Gerais, Brazil.

  16. Crowdsourcing for large-scale mosquito (Diptera: Culicidae) sampling

    Science.gov (United States)

    Sampling a cosmopolitan mosquito (Diptera: Culicidae) species throughout its range is logistically challenging and extremely resource intensive. Mosquito control programmes and regional networks operate at the local level and often conduct sampling activities across much of North America. A method f...

  17. Terrestrial vegetation and aquatic chemistry influence larval mosquito abundance in catch basins, Chicago, USA

    Directory of Open Access Journals (Sweden)

    Gardner Allison M

    2013-01-01

    Full Text Available Abstract Background An important determinant of mosquito-borne pathogen transmission is the spatial distribution of vectors. The primary vectors of West Nile virus (WNV in Illinois are Culex pipiens Linnaeus (Diptera: Culicidae and Culex restuans Theobald. In urban environments, these mosquitoes commonly oviposit in roadside storm water catch basins. However, use of this habitat is inconsistent, with abundance of larvae varying significantly across catch basins at a fine spatial scale. Methods We tested the hypothesis that attributes of the biotic and abiotic environment contribute to spatial and temporal variation in production of mosquito vectors, characterizing the relationship between terrestrial vegetation and aquatic chemistry and Culex abundance in Chicago, Illinois. Larvae were sampled from 60 catch basins from June 14 to October 3, 2009. Density of shrubs and 14 tree genera surrounding the basins were quantified, as well as aquatic chemistry content of each basin. Results We demonstrate that the spatial pattern of Culex abundance in catch basins is strongly influenced by environmental characteristics, resulting in significant variation across the urban landscape. Using regression and machine learning techniques, we described landscape features and microhabitat characteristics of four Chicago neighborhoods and examined the implications of these measures for larval abundance in adjacent catch basins. The important positive predictors of high larval abundance were aquatic ammonia, nitrates, and area of shrubs of height Culex during the fruit-bearing periods and early senescent periods in August and September. Conclusions This study identifies environmental predictors of mosquito production in urban environments. Because an abundance of adult Culex is integral to efficient WNV transmission and mosquitoes are found in especially high densities near larval habitats, identifying aquatic sites for Culex and landscape features that promote

  18. Checklist of the family Simuliidae (Diptera of Finland

    Directory of Open Access Journals (Sweden)

    Jari Ilmonen

    2014-09-01

    Full Text Available A checklist of the family Simuliidae (Diptera is provided for Finland and recognizes 56 species. One new record has been added (Simulium latipes and one name sunken in synonymy (Simulium carpathicum. Furthermore, Simulium tsheburovae is treated as a doubtful record.

  19. [Means of the formation of gonotrophic relations in blood-sucking Diptera].

    Science.gov (United States)

    Tamarina, N A

    1987-01-01

    Gonotrophic relations in low and higher bloodsucking Diptera are fundamentally different that results from an initial type of feeding and trophic behaviour. Trophic behaviour of low dipterous hematophages and gonotrophic harmony peculiar to them can be traced from entomophagy, that is from the predatory mode of life on account of small insects. By the type of the trophic behaviour low bloodsucking Diptera are predators with a typical moment contact with the prey. More primitive is a type of gonotrophic harmony characteristic of hunters for diffusely spread prey (incomplete blood portion provides the maturation of incomplete portion of eggs). Hunting for diffusely spread prey is characteristic of entomophages too. The appearance of gregarious ruminants facilitates the possibility of repeated contacts with prey and blood satiation threshold increases. This is a higher type of gonotrophic harmony providing a maximum realization of potential fecundity. The initial saprophagy of higher Diptera is associated with another type of trophic behaviour (long contact with food substratum) that is a prerequisite for quite a different way of evolution of host-parasite relationships in higher Diptera. This leads to more close connections with the host and excludes gonotrophic harmony. Females were the first to begin the exploitation of vertebrate animals. This is connected with the peculiarities of their behaviour during egg laying such as the stay near animals for laying eggs into fresh dung. Autogeneity, nectarophagy and aphagia are homologous phenomena which reflect the loss of an animal component of food or both components at the level of non-specialized saprophagy rather than secondary loss of bloodsucking. The scheme of gonotrophic relations is given.

  20. Preliminary findings on Bagaza virus (Flavivirus: Flaviviridae growth kinetics, transmission potential & transovarial transmission in three species of mosquitoes

    Directory of Open Access Journals (Sweden)

    A B Sudeep

    2013-01-01

    Full Text Available Background & objectives: Bagaza virus (BAGV, a flavivirus synonymous with Israel turkey meningoencephalitis virus, has been found to circulate in India. BAGV has recently been held responsible for inducing febrile illness in humans and causing unusually high mortality to wild birds in Spain. A study was therefore, undertaken to determine its replication kinetics in certain mosquitoes and to determine vector competence and potential of the mosquitoes to transmit BAGV experimentally. Methods: Aedes aegypti, Culex tritaeniorhynchus and Cx quinquefasciatus mosquitoes were inoculated with BAGV; samples were harvested every day and titrated in BHK-21 cell line. Vector competence and experimental transmission were determined by examining the saliva of infected mosquitoes for virus and induction of sickness in suckling mice, respectively. Results: Cx. tritaeniorhynchus and Ae. aegypti mosquitoes yielded 5 log 10 and 4.67 log 10 TCID 50 /ml of virus on day 3 post-infection (PI, respectively while Cx. quinquefasciatus yielded a titre of 4 log 10 TCID 50 /ml on day 4 PI. BAGV was detected in saliva of all the infected mosquitoes demonstrating their vector competence. Experimental transmission of BAGV to infant mice as well as transovarial transmission was demonstrated by Cx. tritaeniorhynchus but not by Ae. aegypti and Cx. quinquefasciatus mosquitoes. Interpretation & conclusions: Replication of BAGV to high titres and dissemination to saliva in three most prevalent mosquitoes in India is of immense public health importance. Though no major outbreak involving man has been reported yet, BAGV has a potential to cause outbreaks in future.

  1. Infestation of fruit fly, Bactrocera (Diptera: Tephritidae) on mango ...

    African Journals Online (AJOL)

    Infestation of fruit fly, Bactrocera (Diptera: Tephritidae) on mango ( Mangifera indica L.) in peninsular Malaysia. ... Abstract. A survey was carried out in mango orchards in Peninsular Malaysia with aimed to determine the ... HOW TO USE AJOL.

  2. Efectos de la competencia larval en los mosquitos de contenedores artificiales, Aedes aegypti y Culex pipiens (Diptera: Culicidae en condiciones semi-controladas

    Directory of Open Access Journals (Sweden)

    Analía FRANCIA

    2011-01-01

    Full Text Available Las larvas de los mosquitos Aedes aegypti (Linneo y Culex pipiens Linneo pueden criar conjuntamente en pequeños contenedores artificiales de agua, se genera así una competencia interespecífica y/o intraespecífica. El objetivo de este trabajo fue comparar la magnitud relativa de la competencia intra e interespecífica en A. aegypti y C. pipiens, generada durante el desarrollo larval en contenedores artificiales. Las variables medidas como respuesta fueron la supervivencia y el tiempo de desarrollo larval, y la biomasa total producida en estado de pupa. Se criaron larvas de ambos mosquitos en neumáticos de automóvil con agua declorinada y hojarasca. Se introdujeron larvas recién eclosionadas de acuerdo a la densidad (δ estimada según un censo previo de A. aegypti y C. pipiens. Se realizaron los siguientes tratamientos agregando larvas de: (1 A. aegypti hasta alcanzar δ A. aegypti determinada según el censo previo, (2 C. pipiens hasta δ C. pipiens del censo previo, (3 A. aegypti hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo, (4 C. pipiens hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo y (5 A. aegypti y C. pipiens hasta δ A. aegypti y δ C. pipiens del censo previo. Las tres variables medidas fueron afectadas por los tratamientos, excepto la supervivencia y la biomasa producida por C. pipiens. Aedes aegypti fue más alterada por la competencia intraespecífica que por la competencia interespecífica. En C. pipiens, la competencia interespecífica superó en sus efectos a la competencia intraespecífica. Existió asimetría competitiva, ya que C. pipiens fue más afectada por A. aegypti que lo contrario.

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

    Science.gov (United States)

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

    2015-02-01

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

  4. Asymmetric effects of native and exotic invasive shrubs on ecology of the West Nile virus vector Culex pipiens (Diptera: Culicidae).

    Science.gov (United States)

    Gardner, Allison M; Allan, Brian F; Frisbie, Lauren A; Muturi, Ephantus J

    2015-06-16

    Exotic invasive plants alter the structure and function of native ecosystems and may influence the distribution and abundance of arthropod disease vectors by modifying habitat quality. This study investigated how invasive plants alter the ecology of Culex pipiens, an important vector of West Nile virus (WNV) in northeastern and midwestern regions of the United States. Field and laboratory experiments were conducted to test the hypothesis that three native leaf species (Rubus allegheniensis, blackberry; Sambucus canadensis, elderberry; and Amelanchier laevis, serviceberry), and three exotic invasive leaf species (Lonicera maackii, Amur honeysuckle; Elaeagnus umbellata, autumn olive; and Rosa multiflora, multiflora rose) alter Cx. pipiens oviposition site selection, emergence rates, development time, and adult body size. The relative abundance of seven bacterial phyla in infusions of the six leaf species also was determined using quantitative real-time polymerase chain reaction to test the hypothesis that variation in emergence, development, and oviposition site selection is correlated to differences in the diversity and abundance of bacteria associated with different leaf species, important determinants of nutrient quality and availability for mosquito larvae. Leaf detritus from invasive honeysuckle and autumn olive yielded significantly higher adult emergence rates compared to detritus from the remaining leaf species and honeysuckle alleviated the negative effects of intraspecific competition on adult emergence. Conversely, leaves of native blackberry acted as an ecological trap, generating high oviposition but low emergence rates. Variation in bacterial flora associated with different leaf species may explain this asymmetrical production of mosquitoes: emergence rates and oviposition rates were positively correlated to bacterial abundance and diversity, respectively. We conclude that the displacement of native understory plant species by certain invasive shrubs

  5. Blood-feeding ecology of mosquitoes in zoos.

    Science.gov (United States)

    Tuten, H C; Bridges, W C; Paul, K S; Adler, P H

    2012-12-01

    To determine if the unique host assemblages in zoos influence blood-feeding by mosquitoes (Diptera: Culicidae), a sampling programme was conducted in Greenville and Riverbanks Zoos, South Carolina, U.S.A., from April 2009 to October 2010. A total of 4355 female mosquitoes of 14 species were collected, of which 106 individuals of nine species were blood-fed. The most common taxa were Aedes albopictus (Skuse), Aedes triseriatus (Say), Anopheles punctipennis (Say), Culex erraticus (Dyar & Knab), Culex pipiens complex (L.) and Culex restuans (Theobald). Molecular analyses (cytochrome b) of bloodmeals revealed that mosquitoes fed on captive animals, humans and wildlife, and took mixed bloodmeals. Host species included one amphibian, 16 birds, 10 mammals (including humans) and two reptiles. Minimum dispersal distances after feeding on captive hosts ranged from 15.5 m to 327.0 m. Mosquito-host associations generally conformed to previous accounts, indicating that mosquito behaviour inside zoos reflects that outside zoos. However, novel variation in host use, including new, exotic host records, warrants further investigation. Zoos, thus, can be used as experiment environments in which to study mosquito behaviour, and the findings extrapolated to non-zoo areas, while providing medical and veterinary benefits to zoo animals, employees and patrons. © 2012 The Authors. Medical and Veterinary Entomology © 2012 The Royal Entomological Society.

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

    Directory of Open Access Journals (Sweden)

    Tenu Filemoni

    2008-10-01

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

  7. Fate of labelled allitin in bean plant and mosquito

    International Nuclear Information System (INIS)

    Banerji, A.; Chintalwar, G.J.; Ramakrishnan, V.

    1980-01-01

    Allitin, the insecticidal principle of garlic (Allium sativum L) is a mixture of diallyl di- and tri-sulfides. 35 S-labelled allitin has been synthesised using different methods and used for the evaluation of its persistence in water. Results of these experiments showed that allitin has low persistence; more than 80% of the initial radioactivity was lost in 24 hr. when an aqueous emulsion of labelled allitin was exposed under the laboratory conditions. Fate of labelled allitin was studied in larvae and pupae of mosquitoes, Culex pipiens quinquefasciatus Say. Assimilation of allitin was found to be faster in larva compared to pupa. Intake of allitin by bean plant was also studied. Implications of the results obtained in the above experiments will be discussed. (author)

  8. Single-step biological fabrication of colloidal silver nanoparticles using Hugonia mystax: larvicidal potential against Zika virus, dengue, and malaria vector mosquitoes.

    Science.gov (United States)

    Govindarajan, Marimuthu; Kadaikunnan, Shine; Alharbi, Naiyf S; Benelli, Giovanni

    2017-11-01

    Mosquito control is facing key challenges, including outbreaks of new arbovirus threats. We proposed an eco-friendly synthesis of silver nanoparticles (AgNPs) employing a low-cost extract of Hugonia mystax. AgNPs were specified by UV, XRD, FTIR and EDX spectroscopy, SEM and TEM. AgNPs were more toxic to Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus larvae (LC 50 : 14.45, 15.86, and 17.46 μg/mL) if compared to aquatic biocontrol organisms Gambusia affinis, Diplonychus indicus, and Anisops bouvieri (LC 50 : 2567.15, 1075.16, and 829.63 μg/ml). Overall, we shed light on the mosquito larvicidal efficacy of H. mystax, a possible biological resource for low-cost fabrication of AgNPs.

  9. Studies on Anopheles (Kerteszia) homunculus Komp (Diptera: Culicidae)

    Science.gov (United States)

    2009-01-01

    Brasileira de Malariologia e Doenças Tropicais 16, 329–348. Forattini, O.P. (1962) Entomologia médica. Parte geral, Diptera, Anophelini. Vol.1...Estado do Espírito Santo, Brasil. Revista Brasileira de Entomologia 52, 671–673. Schultz, J., Müller, T., Achtziger, M., Seibel, P.N., Dandekar, T

  10. Autogeny induced by a nonsteroidal ecdysone agonist tebufenozide in the mosquito Culex quinquefasciatus

    Czech Academy of Sciences Publication Activity Database

    Gelbič, Ivan; Rozsypalová, Petra

    2012-01-01

    Roč. 37, č. 2 (2012), s. 119-126 ISSN 0307-6962 R&D Projects: GA ČR GA522/08/1407 Institutional research plan: CEZ:AV0Z50070508 Keywords : autogeny * histology * RH-5992 Subject RIV: ED - Physiology Impact factor: 1.417, year: 2012 http://onlinelibrary.wiley.com/doi/10.1111/j.1365-3032.2011.00817.x/pdf

  11. Estimation of larval density of Liriomyza sativae Blanchard (Diptera ...

    African Journals Online (AJOL)

    This study was conducted to develop sequential sampling plans to estimate larval density of Liriomyza sativae Blanchard (Diptera: Agromyzidae) at three precision levels in cucumber greenhouse. The within- greenhouse spatial patterns of larvae were aggregated. The slopes and intercepts of both Iwao's patchiness ...

  12. Effect of gamma radiation on the activity of mosquito culex pipiens

    International Nuclear Information System (INIS)

    Shoman, A. A.M.

    1986-01-01

    The present work was carried out to investigate the effects of gamma radiation at three doses; 40,80 and 120 gray on the response of the adult mosquito culex pipiens complex when irradiated in the larval, pupal or adult stage, to the surrounding environmental factors as light, colour and host. The effects on the sexual activity of the mosquito as sex attraction , ability to inseminate and insemination frequency were also studied. Finally, the effect of 3 low dosages; 20,25 and 30 gray, applied in the pupal stage on the adult female capability to transmit filarial larvae, or in other words on the cycle development of the larvae inside the female body, was also investigated

  13. Nota sobre culicídeos (Diptera: Culicidae da bacia do rio Purus, Acre, Amazônia (Brasil Note on the culicidae (Diptera: Culicidae of the River Purus Basin, Acre, Amazonian, Brazil

    Directory of Open Access Journals (Sweden)

    Delsio Natal

    1992-04-01

    Full Text Available Foram feitas coletas de mosquito (Diptera: Culicidae na área do projeto de Colonização Pedro Peixoto, no Estado do Acre, Brasil. Obteve-se um total de 4.588 exemplares pertencentes a 53 espécies ou grupos. Salienta-se a ocorrência de Anopheles (Nyssorhynchus oswaldoi.Mosquito (Diptera: Culicidae collections were made on the Pedro Peixoto Colonization Project in the State of Acre, Brazil. Four thousand, five hundred and eighty-eight (4,588 specimens were collected and fifty-three (53 species or group recognised. The occurrence of Anopheles (Nyssorhynchus oswaldoi is given special emphasis.

  14. Effective chemical control of fruit flies (Diptera: Tephritidae) pests in ...

    African Journals Online (AJOL)

    Effective chemical control of fruit flies (Diptera: Tephritidae) pests in mango orchards in northern Côte-d'Ivoire. OR N'depo, N Hala, A N'da Adopo, F Coulibaly, PK Kouassi, JF Vayssieres, M de Meyer ...

  15. 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

  16. Resistance Level of Mosquito Species (Diptera: Culicidae from Shandong Province, China

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    Hong-Mei Liu

    2015-01-01

    Full Text Available This study describes the aquatic habitats, species composition, and the insecticide resistance level of the mosquito Culex pipiens pallens in Shandong Province, China. A cross-sectional survey of mosquito larval habitats was conducted from May to November 2014 to determine the species composition and larval abundance. Larvae were collected using the standard dipping technique, and a total of four habitat types were sampled. The fourth instar larvae of Cx. pipiens pallens collected in each habitat type were tested for resistance to five insecticides according to a WHO bioassay. A total of 7,281 mosquito larvae were collected, of which 399 (5.48% were categorized as Anopheles mosquito larvae ( An. sinensis , 6636 (91.14% as culicine larvae ( Cx. pipiens pallens, Cx. tritaeniorhynchus, Cx. halifaxii, and Cx. bitaeniorhynchus , 213 (2.93% as Armigeres larvae, and 33 (0.45% as Aedes larvae ( Aedes albopictus . In addition, a total of 1,149 mosquito pupae were collected. Culex larvae were distributed in all habitats investigated. Tukeys HSD analysis showed that roadside drainages were the most productive habitat type for Culex larvae. Armigeres species were found only in drains, Aedes only in water tanks, and Anopheles in water that was comparatively clear and rich in emergent plants. Bioassay showed that the maximum resistance level of Cx. pipiens pallens was to deltamethrin, while it was lowest to plifenate. The productivity of various mosquitoes in different habitat types is very heterogeneous. It is particularly important to modify human activity and the environment to achieve effective mosquito vector control. For effective larval control, the type of habitat should be considered, and the most productive habitat type should be given priority in mosquito abatement programs.

  17. Avian Plasmodium in Eastern Austrian mosquitoes.

    Science.gov (United States)

    Schoener, Ellen; Uebleis, Sarah Susanne; Butter, Julia; Nawratil, Michaela; Cuk, Claudia; Flechl, Eva; Kothmayer, Michael; Obwaller, Adelheid G; Zechmeister, Thomas; Rubel, Franz; Lebl, Karin; Zittra, Carina; Fuehrer, Hans-Peter

    2017-09-29

    Insect vectors, namely mosquitoes (Diptera: Culicidae), are compulsory for malaria parasites (Plasmodium spp.) to complete their life cycle. Despite this, little is known about vector competence of different mosquito species for the transmission of avian malaria parasites. In this study, nested PCR was used to determine Plasmodium spp. occurrence in pools of whole individuals, as well as the diversity of mitochondrial cytochrome b gene sequences in wild-caught mosquitoes sampled across Eastern Austria in 2013-2015. A total of 45,749 mosquitoes in 2628 pools were collected, of which 169 pools (6.43%) comprising 9 mosquito species were positive for avian Plasmodium, with the majority of positives in mosquitoes of Culex pipiens s.l./Culex torrentium. Six different avian Plasmodium lineages were found, the most common were Plasmodium vaughani SYAT05, Plasmodium sp. Linn1 and Plasmodium relictum SGS1. In 2014, mosquitoes of the Culex pipiens complex were genetically identified and Culex pipiens f. pipiens presented with the highest number of avian Plasmodium positives (n = 37; 16.74%). Despite this, the minimum infection rate (MIR) was highest in Culex torrentium (5.36%) and Culex pipiens f. pipiens/f. molestus hybrids (5.26%). During 2014 and 2015, seasonal and annual changes in Plasmodium lineage distribution were also observed. In both years P. vaughani SYAT05 dominated at the beginning of the sampling period to be replaced later in the year by P. relictum SGS1 (2014) and Plasmodium sp. Linn1 (2015). This is the first large-scale study of avian Plasmodium parasites in Austrian mosquitoes. These results are of special interest, because molecular identification of the taxa of the Cx. pipiens complex and Cx. torrentium enabled the determination of Plasmodium prevalence in the different mosquito taxa and hybrids of this complex. Since pools of whole insects were used, it is not possible to assert any vector competence in any of the examined mosquitoes, but the results

  18. Experimental investigation of the susceptibility of Italian Culex pipiens mosquitoes to Zika virus infection.

    Science.gov (United States)

    Boccolini, Daniela; Toma, Luciano; Di Luca, Marco; Severini, Francesco; Romi, R; Remoli, Maria Elena; Sabbatucci, Michela; Venturi, Giulietta; Rezza, Giovanni; Fortuna, Claudia

    2016-09-01

    We investigated the susceptibility of an Italian population of Culex pipiens mosquitoes to Zika virus (ZIKV) infection, tested in parallel with Aedes aegypti, as a positive control. We analysed mosquitoes at 0, 3, 7, 10, 14, 20 and 24 days after an infectious blood meal. Viral RNA was detected in the body of Cx. pipiens up to three days post-infection, but not at later time points. Our results indicate that Cx. pipiens is not susceptible to ZIKV infection. This article is copyright of The Authors, 2016.

  19. Detection of mosquito-only flaviviruses in Europe

    Czech Academy of Sciences Publication Activity Database

    Calzolari, M.; Zé-Zé, L.; Růžek, Daniel; Vazquez, A.; Jeffries, C.; Defilippo, F.; Osório, H.C.; Kilian, Patrik; Ruíz, S.; Fooks, A. R.; Maioli, G.; Amaro, F.; Tlustý, M.; Figuerola, J.; Medlock, J. M.; Bonilauri, P.; Alves, M. J.; Šebesta, Oldřich; Tenorio, A.; Vaux, A. G. C.; Bellini, R.; Gelbič, Ivan; Sánchez-Seco, M. P.; Johnson, N.; Dottori, M.

    2012-01-01

    Roč. 93, č. 6 (2012), s. 1215-1225 ISSN 0022-1317 R&D Projects: GA MŠk 2B08003; GA MŠk(CZ) LC06009; GA ČR GD206/09/H026 Institutional research plan: CEZ:AV0Z60220518; CEZ:AV0Z50070508; CEZ:AV0Z60930519 Keywords : WEST-NILE-VIRUS * INSECT-SPECIFIC FLAVIVIRUSES * POLYMERASE CHAIN-REACTION * FUSING AGENT VIRUS * AEDES-ALBOPICTUS * CULEX FLAVIVIRUS * DIPTERA-CULICIDAE * PHYLOGENETIC ANALYSIS * SURVEILLANCE * TRANSMISSION Subject RIV: EC - Immunology Impact factor: 3.127, year: 2012 http://link.springer.com/article/10.1007%2Fs00436-012-2928-4

  20. The Community of Hymenoptera Parasitizing Necrophagous Diptera in an Urban Biotope

    Science.gov (United States)

    Frederickx, Christine; Dekeirsschieter, Jessica; Verheggen, François J.; Haubruge, Eric

    2013-01-01

    Most reports published in the field of forensic entomology are focused on Diptera and neglect the Hymenoptera community. However, Hymenoptera are part of the entomofaunal colonization of a dead body. The use of Hymenoptera parasitoids in forensic entomology can be relevant to evaluate the time of death. Hymenoptera parasitoids of the larvae and pupae of flies may play an important role in the estimation of the post-mortem period because their time of attack is often restricted to a small, well-defined window of time in the development of the host insect. However, these parasitoids can interfere with the developmental times of colonizing Diptera, and therefore a better understanding of their ecology is needed. The work reported here monitored the presence of adult Hymenoptera parasitoids on decaying pig carcasses in an urban biotope during the summer season (from May to September). Six families and six species of parasitoids were recorded in the field: Aspilota fuscicornis Haliday (Braconidae), Alysia manducator Panzer, Nasonia vitripennis Walker (Pteromalidae), Tachinaephagus zealandicus Ashmead (Encyrtidae), Trichopria sp. (Diapriidae), and Figites sp. (Figitidae). In the laboratory, five species emerged from pupae collected in the field: Trichopria sp., Figites sp., A. manducator, N. vitripennis, and T. zealandicus. These five species colonize a broad spectrum of Diptera hosts, including those species associated with decomposing carcasses, namely those from the families Calliphoridae, Muscidae, Fanniidae, and Sarcophagidae. PMID:23895458

  1. Correlation between carboxylesterase alleles and insecticide resistance in Culex pipiens complex from China

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    Liu Yangyang

    2011-12-01

    Full Text Available Abstract Background In China, large amounts of chemical insecticides are applied in fields or indoors every year, directly or indirectly bringing selection pressure on vector mosquitoes. Culex pipiens complex has evolved to be resistant to all types of chemical insecticides, especially organophosphates, through carboxylesterases. Six resistant carboxylesterase alleles (Ester were recorded previously and sometimes co-existed in one field population, representing a complex situation for the evolution of Ester genes. Results In order to explore the evolutionary scenario, we analyzed the data from an historical record in 2003 and a recent investigation on five Culex pipiens pallens populations sampled from north China in 2010. Insecticide bioassays showed that these five populations had high resistance to pyrethroids, medium resistance to organophosphates, and low resistance to carbamates. Six types of Ester alleles, EsterB1, Ester2, Ester8, Ester9, EsterB10, and Ester11 were identified, and the overall pattern of their frequencies in geographic distribution was consistent with the report seven years prior to this study. Statistical correlation analysis indicated that Ester8 and Ester9 positively correlated with resistance to four insecticides, and EsterB10 to one insecticide. The occurrences of these three alleles were positively correlated, while the occurrence of EsterB1 was negatively correlated with Ester8, indicating an allelic competition. Conclusion Our analysis suggests that one insecticide can select multiple Ester alleles and one Ester allele can work on multiple insecticides. The evolutionary scenario of carboxylesterases under insecticide selection is possibly "one to many".

  2. Larvicidal, ovicidal, and oviposition-deterrent activities of four plant extracts against three mosquito species.

    Science.gov (United States)

    Prathibha, K P; Raghavendra, B S; Vijayan, V A

    2014-05-01

    In mosquito control programs, insecticides of botanical origin have the potential to eliminate eggs, larvae, and adults. So, the larvicidal, ovicidal, and oviposition-deterrent activities of petroleum ether and ethyl acetate extracts of the leaves of Eugenia jambolana, Solidago canadensis, Euodia ridleyi, and Spilanthes mauritiana were assayed against the three vector mosquito species, namely Anopheles stephensi, Aedes aegypti, and Culex quinquefasciatus. The larval bioassay was conducted following the World Health Organization method. The maximum larval mortality was found with ethyl acetate extract of S. mauritiana against the larvae of A. stephensi, A. aegypti, and C. quinquefasciatus with LC50 values of 11.51, 28.1, 14.10 ppm, respectively. The mean percent hatchability of the ovicidal activity was observed at 48-h post-treatment. The percent hatchability was found to be inversely proportional to the concentration of the extract and directly proportional to the number of eggs. The flower head extract of S. mauritiana gave 100% mortality followed by E. ridleyi, S. canadensis, and E. jambolana against the eggs of the three mosquito vectors. For oviposition-deterrent effect, out of the five concentrations tested (20, 40, 60, 80, and 100 ppm), the concentration of 100 ppm showed a significant egg laying-deterrent capacity. The oviposition activity index value of E. jambolana, E. ridleyi, S. canadensis, and S. mauritiana against A. aegypti, A. stephensi, C. quinquefasciatus at 100 ppm were -0.71, -0.71, -0.90, -0.93, -0.85, -0.91, -1, -1, -0.71, -0.85, -1, and -1, respectively. These results suggest that the leaf/flower extracts of certain local plants have the potential to be developed as possible eco-friendly means for the control of mosquitoes.

  3. Traditional herbal remedies and dietary spices from Cameroon as novel sources of larvicides against filariasis mosquitoes?

    Science.gov (United States)

    Pavela, Roman; Maggi, Filippo; Mbuntcha, Hélène; Woguem, Verlaine; Fogang, Hervet Paulin Dongmo; Womeni, Hilaire Macaire; Tapondjou, Léon Azefack; Barboni, Luciano; Nicoletti, Marcello; Canale, Angelo; Benelli, Giovanni

    2016-12-01

    In Cameroon, many dietary spices are used by traditional healers to cure several diseases such as cancer and microbial infections. Aframomum daniellii, Dichrostachys cinerea and Echinops giganteus are Cameroonian spices widely used as flavourings and as food additives. Moreover, they are traditionally herbal remedies employed to treat several diseases, as well as to control populations of insect pests. In this research, we analysed the chemical composition of A. daniellii, D. cinerea and E. giganteus essential oils and we evaluated their larvicidal potential against larvae of the filariasis and West Nile virus vector Culex quinquefasciatus. The essential oils were obtained from different plant parts by hydrodistillation and their composition was analysed by GC-MS. The three spices exhibited different volatile chemical profiles, being characterized by 1,8-cineole, sabinene and β-pinene (A. daniellii), geraniol and terpinen-4-ol (D. cinerea), and silphiperfol-6-ene and presilphiperfolan-8-ol (E. giganteus). Results showed that the highest larvicidal toxicity on Cx. quinquefasciatus was exerted by D. cinerea essential oil (LC 50  = 39.1 μL L -1 ), followed by A. daniellii (pericarp essential oil: LC 50  = 65.5 μL L -1 ; leaves: LC 50  = 65.5μL L -1 ; seeds: LC 50  = 106.5μL L -1 ) and E. giganteus (LC 50  = 227.4 μL L -1 ). Overall, the chance to use the D. cinerea essential oil against Cx. quinquefasciatus young instars seems promising, since it is effective at moderate doses and could be an advantageous alternative to build newer mosquito control tools.

  4. Invloed van inundatie van graslanden op terrestrische dansmuggen (Diptera: Chironomidae)

    NARCIS (Netherlands)

    Moller Pilot, H.

    2005-01-01

    Influence of flooding on terrestrial chironomids in grassland (Diptera: Chironomidae) Although flooding is an important factor for the invertebrate fauna of grassland, not much is published on this topic. As in other groups the different species of terrestrial Chironomidae display different

  5. New sanitation techniques for controlling tephritid fruit flies (Diptera ...

    African Journals Online (AJOL)

    New approaches to sanitation in a cropping system susceptible to tephritid fruit flies (Diptera tephritidae) in Hawaii have been investigated. Six trials were conducted in tent-like structures to demonstrate that melon fly larvae (Bacrocera cucurbitae, Coquillett) are not reliably controlled by malathion sprayed on the surface of ...

  6. Surface ultrastructure of third-instar Megaselia scalaris (Diptera: Phoridae

    Directory of Open Access Journals (Sweden)

    Sukontason Kabkaew L

    2002-01-01

    Full Text Available We describe some ultrastructure of the third-instar Megaselia scalaris (Diptera: Phoridae using scanning electron microscopy, with the cephalic segment, anterior spiracle and posterior spiracle being emphasized. This study provides the taxonomic information of this larval species, which may be useful to differentiate from other closely-related species.

  7. A check list of necrophagous flies (Diptera: Calyptratae from urban area in Medellín, Colombia Lista de moscas necrófagas (Diptera: Calyptratae del área urbana del municipio de Medellín, Colombia

    Directory of Open Access Journals (Sweden)

    Jorge Alberto Salazar-Ortega

    2012-06-01

    Full Text Available An updated checklist of necrophagous flies (Diptera, Calyptratae occurring in the urban area of Medellín-Colombia is presented. 27 species belonging to 4 families are reported. Data were obtained from field work and recent bibliography references.Se presenta una lista actualizada de moscas necrófagas (Diptera, Calyptratae presentes en el área urbana del municipio de Medellín. Se registran 27 especies incluidas en cuatro familias. Los datos se obtuvieron a partir de recolectas en campo y referencias bibliográficas.

  8. Mosquito (Diptera: Culicidae) fauna in an area endemic for West Nile virus

    Czech Academy of Sciences Publication Activity Database

    Šebesta, Oldřich; Halouzka, Jiří; Hubálek, Zdeněk; Juřicová, Zina; Rudolf, Ivo; Šikutová, Silvie; Svobodová, Petra; Reiter, P.

    2010-01-01

    Roč. 35, č. 1 (2010), s. 156-162 ISSN 1081-1710 EU Projects: European Commission(XE) 10284 - EDEN Institutional research plan: CEZ:AV0Z60930519 Keywords : mosquito es * Anopheles * Aedes * Culex * climate * ecology Subject RIV: FN - Epidemiology, Contagious Diseases ; Clinical Immunology Impact factor: 1.256, year: 2010

  9. Initial survey of predacious diptera on hemlocks in Japan

    Science.gov (United States)

    Hisashi Ohishi; Shigehiko Shiyake; Yorio Miyatake; Ashley Lamb; Michael E. Montgomery

    2011-01-01

    Some species of Coleoptera and Diptera are specialist predators of adelgids. Previously, we reported our survey of predacious Coleoptera on hemlocks in Japan (Shiyake et al. 2008). Two of these beetles, Sasajiscymnus tsugae and Laricobius sp. nov., have been exported to the U.S. for biological control. Here, we provide the first...

  10. Host feeding pattern of Japanese encephalitis virus vector mosquitoes (Diptera: Culicidae) from Kuttanadu, Kerala, India.

    Science.gov (United States)

    Philip Samuel, P; Arunachalam, N; Hiriyan, J; Tyagi, B K

    2008-09-01

    Identification of blood meals of vector mosquitoes is an important tool in the epidemiological investigations of vector-borne diseases. The blood meals of three mosquito species involved in the transmission of Japanese encephalitis virus (JEV) from the Kuttanadu area, Kerala, were determined using the agarose gel diffusion technique. A total of 4959 blood smears belonging to Culex (Culex) tritaeniorhynchus Giles (3273), Cx. (Culex) gelidus Theobald (64), Mansonia (Mnd.) indiana Edwards (735) ,and Ma. (Mnd.) uniformis (Theobald) (887) were tested. Cx. tritaeniorhynchus had predominantly fed on bovids (46.4%), and a good proportion (29%) had fed on more than one host. Cx. tritaeniorhynchus was highly zoophagic, and human feeding accounted for only 1.5% of those individuals successfully tested. Cx. gelidus showed bovid feeding at 36% and pig feeding at 12.5%. The test results showed 42.3% Ma. indiana and 12.2% Ma. uniformis had fed on humans. Multiple feeding was observed in Ma. indiana and Ma. uniformis, and most of the double feedings were from bovids and ovids (7.9 and 20.1%, respectively). Pig feeding accounted for 4.8% of the feedings by Cx. tritaeniorhynchus, 5.3% of Ma. indiana, and 6.4% of Ma. uniformis. This study is significant because of the role played by these mosquitoes in the transmission of JEV in the Kuttanadu area of Kerala, India.

  11. Diptera of sanitary importance associated with composting of biosolids in Argentina

    Directory of Open Access Journals (Sweden)

    Valeria Alejandra Labud

    2003-12-01

    Full Text Available OBJECTIVE: Odorous compounds produced at the biosolids composting plant in Bariloche (NW Patagonia attract a variety of insects, mainly belonging to the order Diptera. In order to characterize these flies, collected specimens were taxonomically identified, their community characteristics were described and their sanitary and synanthropic importance and autochthonous or introduced character were determined. METHODS: Sampling was performed from October 1999 until March 2000. Adults were collected using an entomological net, and larvae and puparia were obtained from the composting material and incubated to obtain adults. Richness, abundance and sex ratio were calculated. RESULTS: A total of 9 taxa of Diptera were identified: Sarconesia chlorogaster, Phaenicia sericata, Calliphora vicina, Cochliomya macellaria, Ophyra sp, Muscina stabulans, Musca domestica, Sarcophaga sp and Fannia sp. Specimens of Anthomyiidae, Acaliptratae and one larva of Eristalis tenax were also found. Ophyra sp. was the most abundant taxa. All the captured Diptera belonged to introduced taxa. Most of them are considered to be eusynanthropic and/or hemisynanthropic and have sanitary importance as they may cause myiasis and pseudomyiasis. The high number of females registered and the finding of immature stages indicated that flies can develop their complete life cycle on biosolid composting windrows. CONCLUSIONS: The characterization of flies obtained in this study may be useful for defining locations of urban or semi-urban composting facilities. It also highlights the importance of sanitary precautions at such plants.

  12. Anomalías morfológicas en diferentes estructuras de cinco especies de Lutzomyia (Diptera: Psychodidae Morphological abnormalities in different structures of five species of Lutzomyia (Diptera: Psychodidae

    Directory of Open Access Journals (Sweden)

    Daniela Vergara

    2008-12-01

    Full Text Available Se describen e ilustran diversos casos de anomalías morfológicas de cinco diferentes especies de Lutzomyia França (Diptera Psychodidae. Estas teratologías se observan en varias estructuras importantes para la identificación taxonómica de dichas especies. Los diferentes individuos pertenecientes a las especies L. columbiana, L. hartmanni, L. reburra, L. ayrozai y L. panamensis fueron capturados en diversos departamentos en Colombia.Diverse morphological anomalies in five different species of Lutzomyia França (Diptera: Pychodidae are described and illustrated. These theratologies are observed in various structures important for the taxonomic identification of the species. The different individuals that belong to the species L. columbiana, L. hartmanni, L. reburra, L. ayrozai and L. panamensis were captured in diverse departments in Colombia.

  13. Zika mosquito vectors: the jury is still out [version 1; referees: 5 approved

    Directory of Open Access Journals (Sweden)

    Walter S. Leal

    2016-10-01

    Full Text Available 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 evidence indicating that the range of mosquito vectors might be wider than anticipated. In particular, three independent groups from Canada, China, and Brazil presented and discussed laboratory and field data strongly suggesting that the southern house mosquito, Culex quinquefasciatus, also known as the common mosquito, is highly likely to be a vector in certain environments.

  14. Zika mosquito vectors: the jury is still out [version 2; referees: 5 approved

    Directory of Open Access Journals (Sweden)

    Walter S. Leal

    2016-11-01

    Full Text Available 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 evidence indicating that the range of mosquito vectors might be wider than anticipated. In particular, three independent groups from Canada, China, and Brazil presented and discussed laboratory and field data strongly suggesting that the southern house mosquito, Culex quinquefasciatus, also known as the common mosquito, is highly likely to be a vector in certain environments.

  15. Mosquito blood-meal analysis for avian malaria study in wild bird communities: laboratory verification and application to Culex sasai (Diptera: Culicidae) collected in Tokyo, Japan.

    Science.gov (United States)

    Kim, Kyeong Soon; Tsuda, Yoshio; Sasaki, Toshinori; Kobayashi, Mutsuo; Hirota, Yoshikazu

    2009-10-01

    We conducted laboratory experiments to verify molecular techniques of avian malaria parasite detection distinguishing between an infected mosquito (oocysts on midgut wall) and infective mosquito (sporozoites in salivary glands) in parallel with blood-meal identification from individual blood-fed mosquitoes prior to application to field survey for avian malaria. Domestic fowl infected with Plasmodium gallinaceum was exposed to a vector and non-vector mosquito species, Aedes aegypti and Culex pipiens pallens, respectively, to compare the time course of polymerase chain reaction (PCR) detection for parasite between competent and refractory mosquitoes. DNA of the domestic fowl was detectable for at least 3 days after blood feeding. The PCR-based detection of P. gallinaceum from the abdomen and thorax of A. aegypti corresponded to the microscopic observation of oocysts and sporozoites. Therefore, this PCR-based method was considered useful as one of the criteria to assess developmental stages of Plasmodium spp. in mosquito species collected in the field. We applied the same PCR-based method to 21 blood-fed C. sasai mosquitoes collected in Rinshi-no-mori Park in urban Tokyo, Japan. Of 15 blood meals of C. sasai successfully identified, 86.7% were avian-derived, 13.3% were bovine-derived. Plasmodium DNA was amplified from the abdomen of three C. sasai specimens having an avian blood meal from the Great Tit (Parus major), Pale Thrush (Turdus pallidus), and Jungle Crow (Corvus macrorhynchos). This is the first field study on host-feeding habits of C. sasai in relation to the potential role as a vector for avian malaria parasites transmitted in the Japanese wild bird community.

  16. Species composition of forensically important blow flies (Diptera: Calliphoridae) and flesh flies (Diptera: Sarcophagidae) through space and time.

    Science.gov (United States)

    Fremdt, Heike; Amendt, Jens

    2014-03-01

    Weekly monitoring of forensically important flight-active blow flies (Diptera: Calliphoridae) and flesh flies (Diptera: Sarcophagidae) was performed using small baited traps. Sampling took place in two rural, one suburban and two urban habitats in and around Frankfurt (Main), Germany, lasting two years and eight months. Highest values for species richness and Chao-Shen entropy estimator for Shannon's index in both families were found at the urban sites, peaking during summer. Space-time interaction was tested and found to be significant, demonstrating the value of a statistical approach recently developed for community surveys in ecology. K-means partitioning and analysis of indicator species gave significant temporal and habitat associations of particular taxa. Calliphora vicina was an indicator species for lower temperatures without being associated with a particular habitat. Lucilia sericata was an indicator for urban sites, whereas Lucilia ampullacea and Lucilia caesar were indicators for rural sites, supplemented by the less frequent species Calliphora vomitoria. Sarcophagidae were observed during a clearly shorter period of year. Sarcophaga subvicina+Sarcophaga variegata was found to be an indicator for urban habitats during summer as well as Sarcophaga albiceps for rural habitats. A significant association of Sarcophaga caerulescens to rural habitats as well as one of Sarcophaga similis to urban habitats was observed. Copyright © 2013 Elsevier Ireland Ltd. All rights reserved.

  17. Evaluation of released malathion and spinosad from chitosan/alginate/gelatin capsules against Culex pipiens larvae

    Directory of Open Access Journals (Sweden)

    Badawy MEI

    2016-09-01

    Full Text Available Mohamed EI Badawy,1 Nehad EM Taktak,2 Osama M Awad,2 Souraya A Elfiki,2 Nadia E Abou El-Ela2 1Department of Pesticide Chemistry and Technology, Faculty of Agriculture, 2Department of Tropical Health, High Institute of Public Health, Alexandria University, Alexandria, Egypt Abstract: Efficacy of spinosad and malathion loaded in eco-friendly biodegradable formulations was evaluated for controlling Culex pipiens larvae. Malathion (organophosphorus larvicide and spinosad (naturally derived insecticide were loaded on chitosan/alginate/gelatin capsules. Capsules were characterized by size measurement, scanning electron microscopy, Fourier transform infrared spectroscopy, and water uptake. In vitro release kinetics of the larvicides was studied in the running and stagnant water. Biochemical studies on the larvae treated with technical and formulated insecticides were also demonstrated. The results indicated that the released spinosad was active for a long time up to 48 and 211 days in the running and stagnant water, respectively. However, the capsules loaded with malathion showed larvicidal activity for 20 and 27 days in the running and stagnant water, respectively. Technical and formulated malathion and spinosad had an inhibition effect on acetylcholinesterase, carboxylesterase, and glutathione S-transferase. The results proved that the prepared capsules consisting of biodegradable polymers containing larvicides could be effective as controlled-release formulation against C. pipiens larvae for a long period. Keywords: chitosan capsules, larvicide, controlled-release formulation, swelling, mosquitocidal activity, Culex pipiens, biochemical study

  18. Karyotypic studies of four species of the blackfly, Simulium (Diptera ...

    African Journals Online (AJOL)

    mallory

    2012-01-12

    Jan 12, 2012 ... Drosophila melanogaster: Practical uses in cell and molecular biology in: Goldstein LSB (Eds). Methods in cell biology. Academic Press Inc. p. 555. Henry W, Dey SK, Varma R (2009). The salivary gland chromosomes of the Himalayan Black fly Simulium (Simulium) dentatum (Diptera: Simuliidae). Zool. Sci.

  19. Characterization of Bacillus thuringiensis soil isolates from Cuba, with insecticidal activity against mosquitoes

    Directory of Open Access Journals (Sweden)

    Aileen González

    2011-09-01

    Full Text Available Chemical insecticides may be toxic and cause environmental degradation. Consequently, biological control for insects represents an alternative with low ecological impact. In this work, three soil isolates (A21, A51 and C17 from different regions of the Cuban archipelago were identified, characterized and evaluated against Aedes aegypti and Culex quinquefasciatus. The new isolates were compared with reference IPS82 strain and two strains isolated from biolarvicides Bactivec and Bactoculicida, respectively. The differentiation was done by morphological, biochemical, bioassays activity and molecular methods (SDS-PAGE, plasmid profile and random amplified polymorphic analysis. All isolates were identified as Bacillus thuringiensis. The A21, A51 and C17 isolates showed higher larvicide activity than Bactivec’s isolated reference strain, against both A. aegypti and C. quinquefasciatus. A21 isolate had a protein profile similar to IPS82 and Bactivec strain. A51 and C17 isolates produced a characteristic proteins pattern. A21 and A51 isolates had plasmid patterns similar to IPS82 standard strain, while C17 isolate had different both plasmid profile and protein bands. All the studied isolates showed a diverse RAPD patterns and were different from the strains previously used in biological control in Cuba. Rev. Biol. Trop. 59 (3: 1007-1016. Epub 2011 September 01.El uso prolongado de insecticidas ha conducido al desarrollo de resistencia en diferentes especies de mosquitos y al incremento de la degradación del ambiente. El control biológico de insectos ha devenido como una alternativa útil y de bajo impacto ambiental. En nuestro estudio fueron identificados, caracterizados tres aislamientos de suelos procedentes de diferentes regiones del archipiélago cubano y comparados con cepas de referencia: aisladas de los biolarvicidas Bactivec y Bactoculicida, además de IPS82. La diferenciación de los mismos se llevó a cabo mediante métodos morfol

  20. Tabanidae and other Diptera on Camel’s Hump Vermont: Ecological Observations

    Directory of Open Access Journals (Sweden)

    Jeffrey Freeman

    2011-11-01

    Full Text Available A canopy trap and aerial nets led to finding 8 species of Tabanidae. There was an abundance of calyptrate muscoid flies. Camel’s Hump is in the Green Mountains of western New England, USA. Discovering Diptera on Camel’s Hump involved sixteen visits over 40 years. Upwards of 23 other Diptera species are listed. Habitats on the east side and above 762 m (2500 ft elevation on Camel’s Hump differ from the west slope but the boreal forest on both sides is influenced by cloud and fog precipitation on trees. The cliffs just above the 900 m level along the east side are often overlooked, are not seen from the summit and provide access to morning sun for insects. Recent visits explored the role of polarized skylight in relation to the canopy trap, the boreal forest environment and flies found there.

  1. The phylogenetic relationships among infraorders and superfamilies of Diptera based on morphological evidence

    DEFF Research Database (Denmark)

    Lambkin, Christine L.; Sinclair, Bradley J.; Pape, Thomas

    2013-01-01

    Members of the megadiverse insect order Diptera (flies) have successfully colonized all continents and nearly all habitats. There are more than 154 000 described fly species, representing 1012% of animal species. Elucidating the phylogenetic relationships of such a large component of global...... biodiversity is challenging, but significant advances have been made in the last few decades. Since Hennig first discussed the monophyly of major groupings, Diptera has attracted much study, but most researchers have used non-numerical qualitative methods to assess morphological data. More recently......, quantitative phylogenetic methods have been used on both morphological and molecular data. All previous quantitative morphological studies addressed narrower phylogenetic problems, often below the suborder or infraorder level. Here we present the first numerical analysis of phylogenetic relationships...

  2. Diptera Brachycera found inside the esophagus of a mummified adult male from the early XIX century, Lisbon, Portugal

    Directory of Open Access Journals (Sweden)

    Márcia Souto Couri

    2008-03-01

    Full Text Available Fly puparia and adult fragments of diptera muscid were found inside the esophagus of a mummified body from the early XIX century, buried inside the crypt of the Sacrament Church (Lisbon, Portugal. The identification of the material revealed a monospecific colonization by Ophyra capensis (Wiedemann (Diptera: Muscidae, a species known to invade corpses in the ammoniacal fermentation wave. This species can be found in corpses kept indoors, not available to the early waves of blowflies (Diptera: Calliphoridae. In the present case, the number of pupae and their developmental stage suggest that the female invaded the mummified corpse through the partially opened mouth and the oviposition took place directly inside the esophagus. This is the first case of O. capensis infesting internal organs of an intact corpse. The use of chemical products for the embalming process probably explains why external colonization did not occur.

  3. Diversity of Bacillus thuringiensis strains in the maize and bean phylloplane and their respective soils in Colombia.

    Science.gov (United States)

    Jara, S; Maduell, P; Orduz, S

    2006-07-01

    To evaluate the distribution of Bacillus thuringiensis strains from maize and bean phylloplane and their respective soils. B. thuringiensis was isolated from the phylloplane and soil of maize and bean from three municipalities in Antioquia, Colombia. Ninety six samples of phylloplane and 24 of soil were analyzed. A total of 214 isolates were obtained from 96 phylloplane samples while 59 isolates were recovered from 24 soil samples. Sixty five per cent and 12% of the phylloplane and soil isolates, respectively, showed activity against Spodoptera frugiperda. These isolates contained delta-endotoxin proteins of 57 and 130 kDa. The most toxic isolates against S. frugiperda had the genotype cry1Aa, cry1Ac, cry1B, and cry1D. In contrast, 27% of the phylloplane isolates and 88% of the soil isolates were active against Culex quinquefasciatus and had protein profiles similar to B. thuringiensis serovar. medellin and B. thuringiensis serovar. israelensis. The most active isolates contain cry4 and cry11 genes. The predominant population of B. thuringiensis on the phylloplane harbored the cry1 gene and was active against S. frugiperda, whereas in soil, isolates harboring cry11 gene and active against C. quinquefasciatus were the majority. The predominance of specific B. thuringiensis populations, both on the leaves and in the soil, suggests the presence of selection in B. thuringiensis populations on the studied environment.

  4. A novel video-tracking system to quantify the behaviour of nocturnal mosquitoes attacking human hosts in the field.

    Science.gov (United States)

    Angarita-Jaimes, N C; Parker, J E A; Abe, M; Mashauri, F; Martine, J; Towers, C E; McCall, P J; Towers, D P

    2016-04-01

    Many vectors of malaria and other infections spend most of their adult life within human homes, the environment where they bloodfeed and rest, and where control has been most successful. Yet, knowledge of peri-domestic mosquito behaviour is limited, particularly how mosquitoes find and attack human hosts or how insecticides impact on behaviour. This is partly because technology for tracking mosquitoes in their natural habitats, traditional dwellings in disease-endemic countries, has never been available. We describe a sensing device that enables observation and recording of nocturnal mosquitoes attacking humans with or without a bed net, in the laboratory and in rural Africa. The device addresses requirements for sub-millimetre resolution over a 2.0 × 1.2 × 2.0 m volume while using minimum irradiance. Data processing strategies to extract individual mosquito trajectories and algorithms to describe behaviour during host/net interactions are introduced. Results from UK laboratory and Tanzanian field tests showed that Culex quinquefasciatus activity was higher and focused on the bed net roof when a human host was present, in colonized and wild populations. Both C. quinquefasciatus and Anopheles gambiae exhibited similar behavioural modes, with average flight velocities varying by less than 10%. The system offers considerable potential for investigations in vector biology and many other fields. © 2016 The Authors.

  5. 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.

  6. Psychoda surcoufi, een motmug van compost, nieuw voor Nederland (Diptera: Psychodidae).

    NARCIS (Netherlands)

    Boumans, L.

    2009-01-01

    Psychoda surcoufi, a mothfly of compost, new to the Netherlands (Diptera: Psychodidae) Psychoda surcoufi Tonnoir, 1922 is reported as a new species for the Dutch checklist. Adults were collected in large numbers in a compost barrel from late February until April 2009, together with P. albipennis

  7. New gall midges (Diptera, Cecidomyiidae) associated with Eugenia uniflora and Psidium cattleianum (Myrtaceae)

    OpenAIRE

    Maia,Valéria C; Nava,Dori E

    2011-01-01

    Two new species and a new genus of gall midges (Diptera, Cecidomyiidae) are described and illustrated. Both species induce leaf galls on Myrtaceae, the former on Eugenia uniflora and the latter on Psidium cattleianum.

  8. Comprehensive inventory of true flies (Diptera) at a tropical site

    Science.gov (United States)

    Brian V. Brown; Art Borkent; Peter H. Adler; Dalton de Souza Amorim; Kevin Barber; Daniel Bickel; Stephanie Boucher; Scott E. Brooks; John Burger; Zelia L. Burington; Renato S. Capellari; Daniel N. R. Costa; Jeffrey M. Cumming; Greg Curler; Carl W. Dick; John H. Epler; Eric Fisher; Stephen D. Gaimari; Jon Gelhaus; David A. Grimaldi; John Hash; Martin Hauser; Heikki Hippa; Sergio Ibanez-Bernal; Mathias Jaschhof; Elena P. Kameneva; Peter H. Kerr; Valery Korneyev; Cheslavo A. Korytkowski; Giar-Ann Kung; Gunnar Mikalsen Kvifte; Owen Lonsdale; Stephen A. Marshall; Wayne Mathis; Verner Michelsen; Stefan Naglis; Allen L. Norrbom; Steven Paiero; Thomas Pape; Alessandre Pereira-Colavite; Marc Pollet; Sabrina Rochefort; Alessandra Rung; Justin B. Runyon; Jade Savage; Vera C. Silva; Bradley J. Sinclair; Jeffrey H. Skevington; John O. Stireman; John Swann; F. Christian Thompson; Pekka Vilkamaa; Terry Wheeler; Terry Whitworth; Maria Wong; D. Monty Wood; Norman Woodley; Tiffany Yau; Thomas J. Zavortink; Manuel A. Zumbado

    2018-01-01

    Estimations of tropical insect diversity generally suffer from lack of known groups or faunas against which extrapolations can be made, and have seriously underestimated the diversity of some taxa. Here we report the intensive inventory of a four-hectare tropical cloud forest in Costa Rica for one year, which yielded 4332 species of Diptera, providing the first...

  9. Systematics and phylogeny of Centrioncidae, a new afromontane family of Diptera (Schizophora)

    NARCIS (Netherlands)

    Feijen, H.R.

    1983-01-01

    Arguments are put forward for the erection of a new family of Diptera, named Centrioncidae. Centrioncus prodiopsis, its only previously described representative, was originally placed in the Sepsidae and later transferred to the Diopsidae. This species is now redescribed and five more Centrioncus

  10. Urban lymphatic filariasis

    DEFF Research Database (Denmark)

    Simonsen, Paul Erik; Mwakitalu, Mbutolwe E.

    2013-01-01

    parasite species causing LF in humans, only Wuchereria bancrofti has been documented to have a significant potential for urban transmission. This is primarily because one of its vectors, Culex quinquefasciatus, thrives and proliferates excessively in crowded city areas with poor sanitary, sewerage...... impact. However, with rapid and unplanned growth of cities in the developing world, there is a need also to consider LF transmission and control in urban settings. Here, we review currently available knowledge on urban LF and the environmental and socio-economic basis for its occurrence. Among the three...... and drainage facilities. For this reason, urban LF also often shows a marked focality in distribution, with most cases clustered in areas inhabited by the less privileged city populations. More knowledge on urban LF is needed, in particular on its socio-economic and human behavioural context, on the potential...

  11. De novo assembly of the Aedes aegypti genome using Hi-C yields chromosome-length scaffolds.

    Science.gov (United States)

    Dudchenko, Olga; Batra, Sanjit S; Omer, Arina D; Nyquist, Sarah K; Hoeger, Marie; Durand, Neva C; Shamim, Muhammad S; Machol, Ido; Lander, Eric S; Aiden, Aviva Presser; Aiden, Erez Lieberman

    2017-04-07

    The Zika outbreak, spread by the Aedes aegypti mosquito, highlights the need to create high-quality assemblies of large genomes in a rapid and cost-effective way. Here we combine Hi-C data with existing draft assemblies to generate chromosome-length scaffolds. We validate this method by assembling a human genome, de novo, from short reads alone (67× coverage). We then combine our method with draft sequences to create genome assemblies of the mosquito disease vectors Ae aegypti and Culex quinquefasciatus , each consisting of three scaffolds corresponding to the three chromosomes in each species. These assemblies indicate that almost all genomic rearrangements among these species occur within, rather than between, chromosome arms. The genome assembly procedure we describe is fast, inexpensive, and accurate, and can be applied to many species. Copyright © 2017, American Association for the Advancement of Science.

  12. Vector species composition and malaria infectivity rates in Mkuzi, Muheza District, north-eastern Tanzania

    DEFF Research Database (Denmark)

    Kweka, E J; Mahande, A M; Nkya, W M M

    2008-01-01

    Entomological surveys were conducted in Mkuzi village in Muheza District, north-east Tanzania from April to September 2003. The objectives were to determine the species composition and infectivity rates of mosquitoes in Mkuzi village. Mosquito collection was done using CDC light trap and pyrethrum...... spray catch (PSC) techniques. The light trap: spray catch ratio was 2.2:1. A total of 2157 mosquitoes were collected (light trap = 1483; PSC = 674). Anopheles gambiae s.s. accounted for 56.7% (N = 1224) of all mosquitoes collected. Other species were An. funestus complex (19.2%) and Culex...... quinquefasciatus (24.1%).The mosquito density per room was 74.15 and 33.7 for light trap and PSC techniques, respectively. A total of 1637 Anopheles mosquitoes were tested for circumsporozoite protein by Enzyme linked Immunosobent Assay (ELISA). The overall infectivity rate for circumsporozoite protein for P...

  13. Toksisitas Insektisida Organofosfat Dan Karbamat Terhadap Nyamuk Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Endang Puji Astuti

    2013-02-01

    Full Text Available Abstract. Aedes aegypti mosquito is increasing problem of public health, being the vector responsible for Dengue and Chikungunya. Chlorpirifos (Organofosfat and Metonil (Carbamate were known to posses insecticide activity against insect. The study was aimed to examine effectiveness of Chlorpirifos and Metonil as insectiside against Ae. aegypti mos­quito Chlorpirifos a significantly higher insecticide activity against Ae. aegypti_than Metonil. The mosquito mortality was observed after 24 h exposure. The LCso value of Chlor­pirifos and Metonil were 0.64 mg/lt and 0,802 mg/lt, against Ae. aegypti mosquito. The mixed of both insecticide was LCso value 108.04 mg/lt, this result prove that mixed of both insecticede not sinergism. The result of th is study suggested that Chlorpirifos more effective insecticide against Ae. aegypti than Metonil. Key Words : Culex quinquefasciatus, insecticide, chlorpirifos, metonil

  14. Host plants of Melon Fly, Bactrocera cucurbitae(Coquillett)(Diptera:Tephritidae); and provisional list of suitable host plants of the Melon Fly, Bactrocera(Zeugodacus)cucurbitae(Coquillett)(Diptera:Tephritidae),Version 2.0

    Science.gov (United States)

    The melon fly, Bactrocera cucurbitae (Coquillett), is a widespread, economically important tephritid fruit fly (Diptera: Tephritidae) species. Bactrocera cucurbitae infests fruits and vegetables of a number of different plant species, with many host plants in the plant family Cucurbitaceae, but with...

  15. Morphology of immature stages of Atherigona reversura (Diptera: Muscidae), with notes on the recent invasion of North America

    DEFF Research Database (Denmark)

    Grzywacz, Andrzej; Pape, Thomas; Hudson, William G.

    2013-01-01

    The muscid shoot-fly Atherigona reversura Villeneuve (Diptera: Muscidae), recently introduced to North America, is reported for the first time from the Neotropical Region: Mexico, Chiapas, Chiapa de Corzo. Information about distribution throughout the continent is summarized. Morphology of the se......The muscid shoot-fly Atherigona reversura Villeneuve (Diptera: Muscidae), recently introduced to North America, is reported for the first time from the Neotropical Region: Mexico, Chiapas, Chiapa de Corzo. Information about distribution throughout the continent is summarized. Morphology...

  16. Crystal and solution structures of an odorant-binding protein from the southern house mosquito complexed with an oviposition pheromone

    Energy Technology Data Exchange (ETDEWEB)

    Mao, Yang; Xu, Xianzhong; Xu, Wei; Ishida, Yuko; Leal, Walter S.; Ames, James B.; Clardy, Jon (Harvard-Med); (UCD)

    2010-11-15

    Culex mosquitoes introduce the pathogens responsible for filariasis, West Nile virus, St. Louis encephalitis, and other diseases into humans. Currently, traps baited with oviposition semiochemicals play an important role in detection efforts and could provide an environmentally friendly approach to controlling their populations. The odorant binding proteins (OBPs) in the female's antenna play a crucial, if yet imperfectly understood, role in sensing oviposition cues. Here, we report the X-ray crystallography and NMR 3D structures of OBP1 for Culex quinquefasciatus (CquiOBP1) bound to an oviposition pheromone (5R,6S)-6-acetoxy-5-hexadecanolide (MOP). In both studies, CquiOBP1 had the same overall six-helix structure seen in other insect OBPs, but a detailed analysis revealed an important previously undescribed feature. There are two models for OBP-mediated signal transduction: (i) direct release of the pheromone from an internal binding pocket in a pH-dependent fashion and (ii) detection of a pheromone-induced conformational change in the OBP {center_dot} pheromone complex. Although CquiOBP1 binds MOP in a pH-dependent fashion, it lacks the C terminus required for the pH-dependent release model. This study shows that CquiOBP binds MOP in an unprecedented fashion using both a small central cavity for the lactone head group and a long hydrophobic channel for its tail.

  17. Abundância de culicídeos em área metropolitana preservada e suas implicações epidemiológicas

    Directory of Open Access Journals (Sweden)

    Taipe-Lagos Carmen Beatriz

    2003-01-01

    Full Text Available OBJETIVO: Estudar a fauna de culicídeos adultos em uma área de reserva na periferia urbana para definir as espécies de interesse em saúde pública. MÉTODOS: O estudo foi realizado no Parque Ecológico do Tietê, localizado na periferia urbana da Grande São Paulo, Brasil. Realizaram-se coletas mensais em três locais e horários distintos, com o uso de aspiradores elétricos, armadilhas CDC e de Shannon no período de agosto de 1996 até março de 1998. O tratamento dos dados baseou-se na estimativa de freqüências e abundâncias. RESULTADOS: Coletaram-se 53.496 exemplares, tendo sido reconhecidas 25 espécies ou grupos genéricos. As espécies Ochlerotatus scapularis, Culex quinquefasciatus e Culex declarator foram as mais freqüentes e abundantes. CONCLUSÕES: As espécies mais freqüentes e abundantes têm demonstrado eficiência na transmissão de agentes patogênicos ao homem em outras regiões. Atenção deve ser dada a esses culicídeos, pois o o local investigado, ao lado de um complexo urbano, reúne condições favoráveis à disseminação de doenças por vetores.

  18. Multiple, independent colonizations of the Hawaiian Archipelago by the family Dolichopodidae (Diptera)

    Czech Academy of Sciences Publication Activity Database

    Goodman, K.R.; Evenhuis, N.; Bartošová-Sojková, Pavla; O'Grady, P. M.

    2016-01-01

    Roč. 4, NOV 17 (2016), č. článku e2704. ISSN 2167-8359 Institutional support: RVO:60077344 Keywords : colonization history * Diptera * divergence dating * Dolichopodidae * evolutionary radiation * long distance dispersal * Hawaiian islands Subject RIV: EB - Genetics ; Molecular Biology Impact factor: 2.177, year: 2016

  19. Cordiamyia globosa gen.n. e sp.n. (Diptera, Cecidomyiidae, Cecidomyiidi associado com Cordia Verbenacea DC. (Boraginaceae no Brasil Cordiamyia globosa gen.n. and sp.n. (Diptera, Cecidomyiidae associated with Cordia verbekacea DC. (Boraginaceae in Brazil

    Directory of Open Access Journals (Sweden)

    Valéria Cid Maia

    1996-01-01

    Full Text Available Cordiamyia globosa gen.n., sp.n. (Diptera, Cecidomyiidae, Cecidomyiidi associated with Cordia verbenacea (Boraginaceae, in Brazil, is described and illustrated (larva, pupa, male, female and gall.

  20. Experimental transmission of West Nile Virus and Rift Valley Fever Virus by Culex pipiens from Lebanon.

    Directory of Open Access Journals (Sweden)

    Renée Zakhia

    2018-01-01

    Full Text Available West Nile virus (WNV and Rift Valley fever virus (RVFV are two emerging arboviruses transmitted by Culex pipiens species that includes two biotypes: pipiens and molestus. In Lebanon, human cases caused by WNV and RVFV have never been reported. However, the introduction of these viruses in the country is likely to occur through the migratory birds and animal trades. In this study, we evaluated the ability of Cx. pipiens, a predominant mosquito species in urban and rural regions in Lebanon, to transmit WNV and RVFV. Culex egg rafts were collected in the West Bekaa district, east of Lebanon and adult females of Cx. pipiens were experimentally infected with WNV and RVFV Clone 13 strain at titers of 1.6×108 and 1.33×107 plaque forming units (PFU/mL, respectively. We estimated viral infection, dissemination and transmission at 3, 7, 14 and 19 days post infection (dpi. Results showed that infection was higher for WNV than for RVFV from 3 dpi to 19 dpi. Viral dissemination and transmission started from 3 dpi for WNV; and only from 19 dpi for RVFV. Moreover, Cx. pipiens were able to excrete in saliva a higher number of viral particles of WNV (1028 ± 405 PFU/saliva at 19 dpi than RVFV (42 PFU/saliva at 19 dpi. Cx. pipiens from Lebanon are efficient experimental vectors of WNV and to a lower extent, RVFV. These findings should stimulate local authorities to establish an active entomological surveillance in addition to animal surveys for both viruses in the country.

  1. The effect of shade on the container index and pupal productivity of the mosquitoes Aedes aegypti and Culex pipiens breeding in artificial containers.

    Science.gov (United States)

    Vezzani, D; Albicócco, A P

    2009-03-01

    The aim of this study was to assess whether certain attributes of larval breeding sites are correlated with pupal productivity (i.e. numbers of pupae collected per sampling period), so that these could be used as the focus for control measures to enhance control efficiency. Therefore, the objectives were to identify the months of highest pupal productivity of Aedes aegypti (L.) and Culex pipiens L. (Diptera: Culicidae) in an urban temperate cemetery in Argentina where artificial containers of containers and to determine whether the composition of the containers affected pupal productivity. Over a period of 9 months, 200 randomly chosen water-filled containers (100 sunlit and 100 shaded), out of approximately 3738 containers present (approximately 54% in shade), were examined each month within a cemetery (5 ha) in Buenos Aires (October 2006 to June 2007). In total, 3440 immatures of Cx pipiens and 1974 of Ae. aegypti were collected. The larvae : pupae ratio was 10 times greater for the former, indicating that larval mortality was greater for Cx pipiens. Both mosquito species showed a higher container index (CI) in shaded than in sunlit containers (Ae. aegypti: 12.8% vs. 6.9% [chi(2) = 17.6, P container and the number of pupae per pupa-positive container did not differ significantly between sunlit and shaded containers for either species. Therefore, the overall relative productivity of pupae per ha of Ae. aegypti and Cx pipiens was 2.3 and 1.8 times greater, respectively, in shaded than in sunlit areas as a result of the greater CIs of containers in shaded areas. Neither the CI nor the number of immatures per infested container differed significantly among container types of different materials in either lighting condition. The maximum CI and total pupal counts occurred in March for Ae. aegypti and in January and February for Cx pipiens. The estimated peak abundance of pupae in the whole cemetery reached a total of approximately 4388 in the middle of March for Ae

  2. Multiple species of scuttle flies (Diptera: Phoridae) as contaminants in forensic entomology laboratory insect colony.

    Science.gov (United States)

    Zuha, R M; Jenarthanan, L X Q; Disney, R H L; Omar, B

    2015-09-01

    In forensic entomology, larval rearing usually includes the presence of biological contaminants including scuttle flies (Diptera: Phoridae). Scuttle flies are recognized as forensically important insects and have been reported causing nuisance and contamination in laboratory environments. This paper reports for the first time the finding of multiple scuttle fly species affecting colonies of third instar larvae of the Oriental latrine blowfly, Chrysomya megacephala (Fabricius) (Diptera: Calliphoridae), reared indoors at the Forensic Science Simulation Site, Universiti Kebangsaan Malaysia. Adult scuttle flies were discovered inside a rearing container after the emergence of adult C. megacephala., The scuttle fly species are Megaselia scalaris (Loew), M. spiracularis Schmitz and Puliciphora borinquenensis (Wheeler). Notes on the life history and biology of these species are discussed herein.

  3. An Algal Diet Accelerates Larval Growth of Anopheles gambiae (Diptera: Culicidae) and Anopheles arabiensis (Diptera: Culicidae).

    Science.gov (United States)

    Tuno, N; Kohzu, A; Tayasu, I; Nakayama, T; Githeko, A; Yan, G

    2018-01-21

    The population sizes of Anopheles gambiae Giles (Diptera: Culicidae) and Anopheles arabiensis Patton (Diptera: Culicidae) increase dramatically with the onset of the rainy season in sub-Saharan Africa, but the ecological mechanisms underlying the increases are not well understood. As a first step toward to understand, we investigated the proliferation of algae, the major food of mosquito larvae, in artificial fresh water bodies exposed to sunlight for a short period, and old water bodies exposed to sunlight for a long period, and the effects thereof on the development of these anopheline larvae. We found that an epizoic green algal species of the genus Rhopalosolen (Chlorophyta: Chlorophyceae) proliferated immediately after water freshly taken from a spring was placed in sunlight. This alga proliferated only briefly (for ~10 d) even if the water was repeatedly exposed to sunlight. However, various algal species were observed in water that remained under sunlight for 40 d or longer (i.e., in old water bodies). The growth performance of larvae was higher in sunlight-exposed (alga-rich) water than in shade-stored (alga-poor) water. Stable isotope analysis suggested that these two anopheline species fed on Rhopalosolen algae in fresh water bodies but hardly at all on other algae occurring in the old water bodies. We concluded that freshly formed ground water pools facilitate high production of anopheline species because of the proliferation of Rhopalosolen algae therein, and the increase in the number of such pools in the rainy season, followed by rapid increases in A. gambiae and A. arabiensis numbers. © The Author(s) 2018. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.

  4. EFEKTIVITAS Bacillus thuringiensis H-14 STRAIN LOKAL DALAM BUAH KELAPA TERHADAP LARVA Anopheles sp dan Culex sp di KAMPUNG LAUT KABUPATEN CILACAP

    Directory of Open Access Journals (Sweden)

    Blondine Ch. P

    2013-07-01

    Full Text Available Abstrak Bacillus thuringiensis serotipe H-14 strain lokal adalah bakteri patogen bersifat target spesifiknya larva nyamuk, aman bagi mamalia dan lingkungan. Penelitian bertujuan menentukan efektivitas B. thuringiensis H-14 strain lokal yang dikembangbiakkan dalam buah kelapa untuk pengendalian larva Anopheles sp dan Culex sp. Rancangan eksperimental semu, terdiri dari kelompok perlakuan dan kontrol. Bacillus thuringiensis H-14 strain lokal dikembangbiakan dalam10 buah kelapa umur 6–8 bulan, dengan berat kira-kira 1 kg, telah berisi air kelapa sekitar 400-500 ml/buah kelapa yang diperoleh dari Desa Klaces, Kampung Laut, Kabupaten Cilacap. Diinkubasi selama 14 hari pada temperatur kamar dan ditebarkan di 6 kolam yang menjadi habitat perkembangbiakan larva nyamuk dengan luas berkisar 3–100 m2.Hasil yang diperoleh menunjukkan efektivitas B. thuringiensis H-14 strain lokal terhadap larva Anopheles sp dan Culex sp selama 1 hari sesudah penebaran kematian larva berturut-turut sebesar 80–100% dan 79,31–100%. Sedangkan pada hari ke-14 sebesar 69,30–76,71% dan 67,69–86,04%. Buah kelapa dapat digunakan sebagai media lokal alternatif untuk pengembangbiakan B. thuringiensis H-14 strain lokal Kata kunci: B. thuringiensis H-14,  strain  lokal, buah kelapa, pengendalian larva Abstract Bacillus thuringiensis serotype H-14 local strain is pathogenic bacteria which specific  target to mosquito larvae. It is safe for mammals and enviroment. The aims of this study was to determine the effectivity of B. thuringiensis H-14 local strain which culturing in thecoconut wates against Anopheles sp and Culex sp mosquito larvae. This research is quasi experiment which consist of treated  and control groups. Bacillus thuringiensis H-14 local strain was cultured in 10 coconuts with 6–8 months age with weight around 1 kg that contained were approximately 400-500 ml/coconut were taken from Klaces village, Kampung Laut. After that the coconuts incubated for 14

  5. Host plants of Carambola fruit fly, Bactrocera carambolae Drew & Hancock(Diptera:Tephritidae);and provisional list of suitable host plants of Carambola fruit fly,(Bactrocera(Bactrocera) carambolae Drew & Hancock(Diptera:Tep

    Science.gov (United States)

    Bactrocera carambolae Drew & Hancock (Diptera: Tephritidae), commonly known as the carambola fruit fly, is native to Southeast Asia, but has extended its geographic range to several countries in South America. As with other tephritid fruit fly species, establishment of B.carambolae in areas where it...

  6. Übersicht der bisher in Europa beobachteten, an Spinnen (Araneae) parasitierenden Fliegen (Diptera)

    OpenAIRE

    Kreuels, Martin

    1998-01-01

    A list of european parasitic flies (Diptera) and their prey is presented. The Hippoboscidae: Melophagus ovinus (Linnaeus, 1758) is described as an accidental parasite of Alopecosa striatipes (C.L. Koch, 1837). 24 species of parsitic flies and 20 spider host species are listed.

  7. Rehydration of forensically important larval Diptera specimens.

    Science.gov (United States)

    Sanford, Michelle R; Pechal, Jennifer L; Tomberlin, Jeffery K

    2011-01-01

    Established procedures for collecting and preserving evidence are essential for all forensic disciplines to be accepted in court and by the forensic community at large. Entomological evidence, such as Diptera larvae, are primarily preserved in ethanol, which can evaporate over time, resulting in the dehydration of specimens. In this study, methods used for rehydrating specimens were compared. The changes in larval specimens with respect to larval length and weight for three forensically important blow fly (Diptera: Calliphoridae) species in North America were quantified. Phormia regina (Meigen), Cochliomyia macellaria (F.), and Chrysomya rufifacies (Macquart) third-instar larvae were collected from various decomposing animals and preserved with three preservation methods (80% ethanol, 70% isopropyl alcohol, and hot-water kill then 80% ethanol). Preservative solutions were allowed to evaporate. Rehydration was attempted with either of the following: 80% ethanol, commercial trisodium phosphate substitute solution, or 0.5% trisodium phosphate solution. All three methods partially restored weight and length of specimens recorded before preservation. Analysis of variance results indicated that effects of preservation, rehydration treatment, and collection animal were different in each species. The interaction between preservative method and rehydration treatment had a significant effect on both P. regina and C. macellaria larval length and weight. In addition, there was a significant interaction effect of collection animal on larval C. macellaria measurements. No significant effect was observed in C. rufifacies larval length or weight among the preservatives or treatments. These methods could be used to establish a standard operating procedure for dealing with dehydrated larval specimens in forensic investigations.

  8. SYBR green-based one step quantitative real-time polymerase chain reaction assay for the detection of Zika virus in field-caught mosquitoes.

    Science.gov (United States)

    Tien, Wei-Ping; Lim, Gareth; Yeo, Gladys; Chiang, Suzanna Nicole; Chong, Chee-Seng; Ng, Lee-Ching; Hapuarachchi, Hapuarachchige Chanditha

    2017-09-19

    The monitoring of vectors is one of the key surveillance measures to assess the risk of arbovirus transmission and the success of control strategies in endemic regions. The recent re-emergence of Zika virus (ZIKV) in the tropics, including Singapore, emphasizes the need to develop cost-effective, rapid and accurate assays to monitor the virus spread by mosquitoes. As ZIKV infections largely remain asymptomatic, early detection of ZIKV in the field-caught mosquitoes enables timely implementation of appropriate mosquito control measures. We developed a rapid, sensitive and specific real-time reverse transcription polymerase chain reaction (rRT-PCR) assay for the detection of ZIKV in field-caught mosquitoes. The primers and PCR cycling conditions were optimized to minimize non-specific amplification due to cross-reactivity with the genomic material of Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, Culex tritaeniorhynchus, Culex sitiens and Anopheles sinensis, as well as accompanying microbiota. The performance of the assay was further evaluated with a panel of flaviviruses and alphaviruses as well as in field-caught Ae. aegypti mosquitoes confirmed to be positive for ZIKV. As compared to a probe-based assay, the newly developed assay demonstrated 100% specificity and comparable detection sensitivity for ZIKV in mosquitoes. Being a SYBR Green-based method, the newly-developed assay is cost-effective and easy to adapt, thus is applicable to large-scale vector surveillance activities in endemic countries, including those with limited resources and expertise. The amplicon size (119 bp) also allows sequencing to confirm the virus type. The primers flank relatively conserved regions of ZIKV genome, so that, the assay is able to detect genetically diverse ZIKV strains. Our findings, therefore, testify the potential use of the newly-developed assay in vector surveillance programmes for ZIKV in endemic regions.

  9. Diptera of Medico-Legal Importance Associated With Pig Carrion in a Tropical Dry Forest.

    Science.gov (United States)

    Vasconcelos, S D; Salgado, R L; Barbosa, T M; Souza, J R B

    2016-06-20

    The diversity of necrophagous Diptera is largely unknown in seasonally dry tropical forests, despite their medical, veterinary, and forensic relevance. We performed a study in the dry Caatinga forest exclusive to Brazil in order to assess the diversity and temporal pattern of Diptera species using pig carcasses as substrates. Adults were collected daily until complete skeletonization. We collected 17,142 adults from 18 families, 10 of which comprise species with known necrophagous habits. The most abundant families were Calliphoridae (47.3% of specimens), Sarcophagidae (20.8%), and Muscidae (15.5%), whereas Sarcophagidae stood out in terms of richness with 21 species. The native Cochliomyia macellaria (F.) (Diptera: Calliphoridae) and the invasive Chrysomya albiceps (Wiedmann) (Calliphoridae) were the dominant species. A total of 18 species reached the carcass during the first 48 h postdeath. The bloated and active decay stages had the highest richness and abundance of dipterans. From a forensic standpoint, C. macellaria and C. albiceps are likely to aid in establishing postmortem interval due to their early arrival and high abundance on the carcass. Despite harsh environmental conditions, the Caatinga harbors a rich assemblage of dipterans that play a key role in carrion decomposition. Their medico-veterinary importance is strengthened by the poor local sanitary conditions. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

  10. Análise cladística de Euprepina Hull (Diptera, Bombyliidae, Bombyliinae Cladistic analysis of Euprepina Hull, (Diptera, Bombyliidae, Bombyliinae

    Directory of Open Access Journals (Sweden)

    Carlos José Einicker Lamas

    1999-01-01

    Full Text Available A cladistic analysis of Euprepina Hull, 1971 (Diptera, Bombyliidae, Bombyliinae, a Neotropical genus that includes ten species, was made. The cladogram was obtained from eight studied species, based on a data matrix with 21 characters, using the program Hennig86. Character states were polarized following outgroup analysis, and an hypothetical ancestor was included in the analysis in order to root the tree. The options used, "ie*" and "xs w", resulted in four most parsimonious trees with ci = 79, ri = 80 and length 115. The monophiletism of Euprepina was supported by two synapomorphies.

  11. New records of diptera families Anisopodidae, Bibionidae, Dixidae, Ptychopteridae and Scatopsidae from Armenia

    Czech Academy of Sciences Publication Activity Database

    Oboňa, J.; Dvořák, L.; Haenni, J.-P.; Manko, P.; Hrivniak, Ľuboš; Papyan, L.

    2017-01-01

    Roč. 40, č. 1 (2017), s. 61-67 ISSN 0341-8391 Institutional support: RVO:60077344 Keywords : biodiversity hotspots * Armenia * Diptera Subject RIV: EG - Zoology OBOR OECD: Zoology Impact factor: 0.784, year: 2016 http://pfeil-verlag.de/publikationen/spixiana-zeitschrift-fuer-zoologie-band-40/

  12. Prevalencia de infección por el virus del Nilo Occidental en dos zoológicos del estado de Tabasco Prevalence of West Nile Virus infection in animals from two state zoos Tabasco

    Directory of Open Access Journals (Sweden)

    M Hidalgo-Martínez

    2008-02-01

    Full Text Available OBJETIVO: Determinar la prevalencia de infección por el virus del Nilo Occidental (VNO en animales, mosquitos y personal que labora en dos zoológicos del estado de Tabasco, en México. MATERIAL Y MÉTODOS: Con la utilización de ELISA de bloqueo se detectaron anticuerpos en sueros de animales: se buscó un fragmento del genoma del VNO por RT-PCR en el suero de animales, empleados y mosquitos. RESULTADOS: En el zoológico "La Venta" se encontró una seroprevalencia de 25.67% (19/74 en aves y de 85.71% (6/7 en reptiles. En el zoológico "Yum-Ká", 31.25% (50/160 de las aves y 34.48% (16/29, de los mamíferos