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Sample records for aedes aegypti females

  1. Especificidade da armadilha Adultrap para capturar fêmeas de Aedes aegypti (Diptera: Culicidae Specificity of the Adultrap for capturing females of Aedes aegypti (Diptera: Culicidae

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    Almério de Castro Gomes

    2007-04-01

    Full Text Available A Adultrap é uma nova armadilha feita para capturar fêmeas de Aedes aegypti. Foram realizados testes para avaliar sua especificidade tendo como referência a técnica da aspiração da espécie em abrigos artificiais. A Adultrap ficou exposta por 24 horas no intradomicílio e peridomicílio de 120 casas sorteadas em dois bairros da Cidade de Foz do Iguaçu, Estado do Paraná. O teste estatístico foi o modelo log-linear de Poisson. O resultado foi a captura de 726 mosquitos Culicidae, dos quais 80 eram Aedes aegypti. A Adultrap capturou apenas fêmeas desta espécie, enquanto o aspirador os dois sexos de Aedes aegypti e mais cinco outras espécies. A Adultrap capturou Aedes aegypti dentro e fora das casas, mas a análise indicou que no peridomicílio a armadilha capturou significantemente mais fêmeas do que a aspiração. Também, ficou evidenciada a sensibilidade da Adultrap para detectar Aedes aegypti em situação de baixa freqüência.The Adultrap is a new trap built for capturing females of Aedes aegypti. Tests were carried out to evaluate the specificity of this trap in comparison with the technique of aspiration of specimens in artificial shelters. Adultraps were kept for 24 hours inside and outside 120 randomly selected homes in two districts of the city of Foz do Iguaçú, State of Paraná. The statistical test was Poisson’s log-linear model. The result was 726 mosquitoes captured, of which 80 were Aedes aegypti. The Adultrap captured only females of this species, while the aspiration method captured both sexes of Aedes aegypti and another five species. The Adultrap captured Aedes aegypti inside and outside the homes, but the analysis indicated that, outside the homes, this trap captured significantly more females than aspiration did. The sensitivity of the Adultrap for detecting females of Aedes aegypti in low-frequency situations was also demonstrated.

  2. Indoor volatiles of primary school classrooms in Tapachula, Chiapas, Mexico, are attractants to Aedes aegypti females

    NARCIS (Netherlands)

    Estrada, J.L.T.; Delgado, S.M.R.; Takken, W.

    2013-01-01

    We determined the behavioral response of Aedes aegypti females to volatile compounds collected in indoor primary school classrooms. Volatiles were collected from classrooms from 0800 through 1030 h and 1130 through 1400 h in urban and rural schools in Tapachula, Chiapas, Mexico. Female responses to

  3. The Siren's Song: Exploitation of Female Flight Tones to Passively Capture Male Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

    The need to capture male mosquitoes has intensified recently as a result of a number of male-based sterile insect technique (SIT) and population-modification programs focused on Aedes aegypti (L.) having initiated field releases. Here, we report the results of the successful exploitation of the attraction of male Ae. aegypti to female flight tones to enhance male collections in nonmechanical passive (nonbattery powered) Gravid Aedes Traps (GAT). Prior to field studies, male attraction to female flight tones of 484 and 560 Hz, as well as to a male flight tone of 715 Hz, were assessed in a series of controlled release-recapture and semifield trials. These trials determined that a pure tone of 484 Hz was significantly more attractive to free-flying males than the other flight tones and enabled their collection in sound-baited GATs (ca. 95% capture rate after 2 h; 484 Hz at 65 dB). In contrast, gravid females were unresponsive to male or female flight tones and were evenly distributed among sound-baited and control GATs. Importantly, under normal field conditions sound-baited GATs (484 Hz at 70 dB) captured significantly more male Ae. aegypti per 24-h trap interval (1.3 ± 0.37) than controls (0.2 ± 0.13). Overall, sound-bated GATs captured approximately twice as many Ae. aegypti (male and female; 3.0 ± 0.68 per interval, 30 total) than controls (1.5 ± 0.56 per interval, 15 total). These results reveal that sound-baited GATs are a simple and effective surveillance tool for Ae. aegypti that would allow current male-based SIT and population-modification programs to effectively monitor males in their target populations. PMID:26502754

  4. The Siren's Song: Exploitation of Female Flight Tones to Passively Capture Male Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

    The need to capture male mosquitoes has intensified recently as a result of a number of male-based sterile insect technique (SIT) and population-modification programs focused on Aedes aegypti (L.) having initiated field releases. Here, we report the results of the successful exploitation of the attraction of male Ae. aegypti to female flight tones to enhance male collections in nonmechanical passive (nonbattery powered) Gravid Aedes Traps (GAT). Prior to field studies, male attraction to female flight tones of 484 and 560 Hz, as well as to a male flight tone of 715 Hz, were assessed in a series of controlled release-recapture and semifield trials. These trials determined that a pure tone of 484 Hz was significantly more attractive to free-flying males than the other flight tones and enabled their collection in sound-baited GATs (ca. 95% capture rate after 2 h; 484 Hz at 65 dB). In contrast, gravid females were unresponsive to male or female flight tones and were evenly distributed among sound-baited and control GATs. Importantly, under normal field conditions sound-baited GATs (484 Hz at 70 dB) captured significantly more male Ae. aegypti per 24-h trap interval (1.3 ± 0.37) than controls (0.2 ± 0.13). Overall, sound-bated GATs captured approximately twice as many Ae. aegypti (male and female; 3.0 ± 0.68 per interval, 30 total) than controls (1.5 ± 0.56 per interval, 15 total). These results reveal that sound-baited GATs are a simple and effective surveillance tool for Ae. aegypti that would allow current male-based SIT and population-modification programs to effectively monitor males in their target populations.

  5. Global dynamics of a PDE model for aedes aegypti mosquitoe incorporating female sexual preference

    KAUST Repository

    Parshad, Rana

    2011-01-01

    In this paper we study the long time dynamics of a reaction diffusion system, describing the spread of Aedes aegypti mosquitoes, which are the primary cause of dengue infection. The system incorporates a control attempt via the sterile insect technique. The model incorporates female mosquitoes sexual preference for wild males over sterile males. We show global existence of strong solution for the system. We then derive uniform estimates to prove the existence of a global attractor in L-2(Omega), for the system. The attractor is shown to be L-infinity(Omega) regular and posess state of extinction, if the injection of sterile males is large enough. We also provide upper bounds on the Hausdorff and fractal dimensions of the attractor.

  6. Transmission of Beauveria bassiana from male to female Aedes aegypti mosquitoes

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    Reyes-Villanueva Filiberto

    2011-02-01

    Full Text Available Abstract Background Resistance to chemical insecticides plus high morbidity rates have lead to rising interest in fungi as candidates for biocontrol agents of mosquito vectors. In most studies fungal infections have been induced by exposure of mosquitoes to various surfaces treated with conidia. In the present study eight Mexican strains of Beauveria bassiana were assessed against Aedes aegypti by direct exposure of females to 6 × 108 conidia ml -1 on a filter paper, afterwards, the transmission of the least and most virulent isolates was evaluated by mating behavior from virgin, fungus-contaminated male to females, to examine this ethological pattern as a new approach to deliver conidia against the dengue vector. Methods In an exposure chamber with a filter paper impregnated with 6 × 108 conidia ml -1 of the least and most virulent strains of B. bassiana, 6-8 day old males of A. aegypti were exposed for 48 hours, and then transferred individually (each one was a replicate to another chamber and confined with twenty healthy females of the same age. Clean males were used in controls. Survival, infection by true mating (insemination or by mating attempts (no insemination and fecundity were daily registered until the death of last female. Data analysis was conducted with proc glm for unbalanced experiments and means were separated with the Ryan test with SAS. Results All strains were highly virulent with LT50 ranging from 2.70 (± 0.29 to 5.33 (± 0.53 days. However the most (Bb-CBG2 and least virulent (Bb-CBG4 isolates were also transmitted by mating behavior; both killed 78-90% of females in 15 days after being confined with males that had previously been exposed for 48 hours to fungi. Of these mortality rates, 23 and 38% respectively, were infections acquired by copulations where insemination occurred. The LT50 for sexually-infected females were 7.92 (± 0.46 and 8.82 (± 0.45 days for both strains, while the one in control was 13.92 (± 0

  7. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

    Science.gov (United States)

    Mysore, Keshava; Sun, Longhua; Tomchaney, Michael; Sullivan, Gwyneth; Adams, Haley; Piscoya, Andres S; Severson, David W; Syed, Zainulabeuddin; Duman-Scheel, Molly

    2015-11-01

    The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx), a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation. PMID:26544686

  8. siRNA-Mediated Silencing of doublesex during Female Development of the Dengue Vector Mosquito Aedes aegypti.

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    Keshava Mysore

    2015-11-01

    Full Text Available The development of sex-specific traits, including the female-specific ability to bite humans and vector disease, is critical for vector mosquito reproduction and pathogen transmission. Doublesex (Dsx, a terminal transcription factor in the sex determination pathway, is known to regulate sex-specific gene expression during development of the dengue fever vector mosquito Aedes aegypti. Here, the effects of developmental siRNA-mediated dsx silencing were assessed in adult females. Targeting of dsx during A. aegypti development resulted in decreased female wing size, a correlate for body size, which is typically larger in females. siRNA-mediated targeting of dsx also resulted in decreased length of the adult female proboscis. Although dsx silencing did not impact female membrane blood feeding or mating behavior in the laboratory, decreased fecundity and fertility correlated with decreased ovary length, ovariole length, and ovariole number in dsx knockdown females. Dsx silencing also resulted in disruption of olfactory system development, as evidenced by reduced length of the female antenna and maxillary palp and the sensilla present on these structures, as well as disrupted odorant receptor expression. Female lifespan, a critical component of the ability of A. aegypti to transmit pathogens, was also significantly reduced in adult females following developmental targeting of dsx. The results of this investigation demonstrate that silencing of dsx during A. aegypti development disrupts multiple sex-specific morphological, physiological, and behavioral traits of adult females, a number of which are directly or indirectly linked to mosquito reproduction and pathogen transmission. Moreover, the olfactory phenotypes observed connect Dsx to development of the olfactory system, suggesting that A. aegypti will be an excellent system in which to further assess the developmental genetics of sex-specific chemosensation.

  9. Susceptibility of adult female Aedes aegypti (Diptera: Culicidae to the entomopathogenic fungus Metarhizium anisopliae is modified following blood feeding

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    Samuels Richard I

    2011-05-01

    Full Text Available Abstract Background The mosquito Aedes aegypti, vector of dengue fever, is a target for control by entomopathogenic fungi. Recent studies by our group have shown the susceptibility of adult A. aegypti to fungal infection by Metarhizium anisopliae. This fungus is currently being tested under field conditions. However, it is unknown whether blood-fed A. aegypti females are equally susceptible to infection by entomopathogenic fungi as sucrose fed females. Insect populations will be composed of females in a range of nutritional states. The fungus should be equally efficient at reducing survival of insects that rest on fungus impregnated surfaces following a blood meal as those coming into contact with fungi before host feeding. This could be an important factor when considering the behavior of A. aegypti females that can blood feed on multiple hosts over a short time period. Methods Female A. aegypti of the Rockefeller strain and a wild strain were infected with two isolates of the entomopathogenic fungus M. anisopliae (LPP 133 and ESALQ 818 using an indirect contact bioassay at different times following blood feeding. Survival rates were monitored on a daily basis and one-way analysis of variance combined with Duncan's post-hoc test or Log-rank survival curve analysis were used for statistical comparisons of susceptibility to infection. Results Blood feeding rapidly reduced susceptibility to infection, determined by the difference in survival rates and survival curves, when females were exposed to either of the two M. anisopliae isolates. Following a time lag which probably coincided with digestion of the blood meal (96-120 h post-feeding, host susceptibility to infection returned to pre-blood fed (sucrose fed levels. Conclusions Reduced susceptibility of A. aegypti to fungi following a blood meal is of concern. Furthermore, engorged females seeking out intra-domicile resting places post-blood feeding, would be predicted to rest for prolonged

  10. Rhamnolipids: solution against Aedes aegypti?

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    Vinicius Luiz Silva

    2015-02-01

    Full Text Available Aedes aegypti mosquitoes are the primary transmitters of dengue fever, urban yellow fever and chikungunya viruses. This mosquito has developed resistance to the insecticides currently used to control their populations. These chemical insecticides are harmful to the environment and can have negative effects on human health. Rhamnolipids are environmentally compatible biological surfactants, but their insecticidal activity has not been extensively studied. The present study evaluated the potential larvicidal, insecticidal and repellent activities of rhamnolipids against Aedes aegypti. At concentrations of 800, 900 and 1000 mg/L, rhamnolipids eliminated all mosquito larvae in 18 hours and killed 100% of adults at 1000 mg/L. According to the results it may be conclude that rhamnolipids should be applied to control larvae and mosquitos besides present the repellency activity against Aedes aegypti.

  11. Detection of all four dengue serotypes in Aedes aegypti female mosquitoes collected in a rural area in Colombia

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    Rosalía Pérez-Castro

    2016-04-01

    Full Text Available The Aedes aegypti vector for dengue virus (DENV has been reported in urban and periurban areas. The information about DENV circulation in mosquitoes in Colombian rural areas is limited, so we aimed to evaluate the presence of DENV in Ae. aegypti females caught in rural locations of two Colombian municipalities, Anapoima and La Mesa. Mosquitoes from 497 rural households in 44 different rural settlements were collected. Pools of about 20 Ae. aegypti females were processed for DENV serotype detection. DENV in mosquitoes was detected in 74% of the analysed settlements with a pool positivity rate of 62%. The estimated individual mosquito infection rate was 4.12% and the minimum infection rate was 33.3/1,000 mosquitoes. All four serotypes were detected; the most frequent being DENV-2 (50% and DENV-1 (35%. Two-three serotypes were detected simultaneously in separate pools. This is the first report on the co-occurrence of natural DENV infection of mosquitoes in Colombian rural areas. The findings are important for understanding dengue transmission and planning control strategies. A potential latent virus reservoir in rural areas could spill over to urban areas during population movements. Detecting DENV in wild-caught adult mosquitoes should be included in the development of dengue epidemic forecasting models.

  12. Flavivirus susceptibility in Aedes aegypti.

    Science.gov (United States)

    Black, William C; Bennett, Kristine E; Gorrochótegui-Escalante, Norma; Barillas-Mury, Carolina V; Fernández-Salas, Ildefonso; de Lourdes Muñoz, María; Farfán-Alé, José A; Olson, Ken E; Beaty, Barry J

    2002-01-01

    Aedes aegypti is the primary vector of yellow fever (YF) and dengue fever (DF) flaviviruses worldwide. In this review we focus on past and present research on genetic components and environmental factors in Aedes aegypti that appear to control flavivirus transmission. We review genetic relationships among Ae. aegypti populations throughout the world and discuss how variation in vector competence is correlated with overall genetic differences among populations. We describe current research into how genetic and environmental factors jointly affect distribution of vector competence in natural populations. Based on this information, we propose a population genetic model for vector competence and discuss our recent progress in testing this model. We end with a discussion of approaches being taken to identify the genes that may control flavivirus susceptibility in Ae. aegypti. PMID:12234528

  13. Dispersal of Engineered Male Aedes aegypti Mosquitoes

    OpenAIRE

    Peter Winskill; Carvalho, Danilo O.; Capurro, Margareth L.; Luke Alphey; Donnelly, Christl A.; McKemey, Andrew R.

    2015-01-01

    Background Aedes aegypti, the principal vector of dengue fever, have been genetically engineered for use in a sterile insect control programme. To improve our understanding of the dispersal ecology of mosquitoes and to inform appropriate release strategies of ‘genetically sterile’ male Aedes aegypti detailed knowledge of the dispersal ability of the released insects is needed. Methodology/Principal Findings The dispersal ability of released ‘genetically sterile’ male Aedes aegypti at a field ...

  14. Dispersal of Engineered Male Aedes aegypti Mosquitoes.

    OpenAIRE

    Peter Winskill; Carvalho, Danilo O.; Capurro, Margareth L.; Luke Alphey; Donnelly, Christl A.; McKemey, Andrew R.

    2015-01-01

    Aedes aegypti, the principal vector of dengue fever, have been genetically engineered for use in a sterile insect control programme. To improve our understanding of the dispersal ecology of mosquitoes and to inform appropriate release strategies of 'genetically sterile' male Aedes aegypti detailed knowledge of the dispersal ability of the released insects is needed.The dispersal ability of released 'genetically sterile' male Aedes aegypti at a field site in Brazil has been estimated. Dispersa...

  15. Rhamnolipids: solution against Aedes aegypti?

    OpenAIRE

    Silva, Vinicius L.; Lovaglio, Roberta B.; Claudio J. Von Zuben; Contiero, Jonas

    2015-01-01

    Aedes aegypti mosquitoes are the primary transmitters of dengue fever, urban yellow fever, and chikungunya viruses. This mosquito has developed resistance to the insecticides currently used to control their populations. These chemical insecticides are harmful to the environment and can have negative effects on human health. Rhamnolipids are environmentally compatible biological surfactants, but their insecticidal activity has not been extensively studied. The present study evaluated the poten...

  16. Midgut bacterial dynamics in Aedes aegypti.

    Science.gov (United States)

    Terenius, Olle; Lindh, Jenny M; Eriksson-Gonzales, Karolina; Bussière, Luc; Laugen, Ane T; Bergquist, Helen; Titanji, Kehmia; Faye, Ingrid

    2012-06-01

    In vector mosquitoes, the presence of midgut bacteria may affect the ability to transmit pathogens. We have used a laboratory colony of Aedes aegypti as a model for bacterial interspecies competition and show that after a blood meal, the number of species (culturable on Luria-Bertani agar) that coexist in the midgut is low and that about 40% of the females do not harbor any cultivable bacteria. We isolated species belonging to the genera Bacillus, Elizabethkingia, Enterococcus, Klebsiella, Pantoea, Serratia, and Sphingomonas, and we also determined their growth rates, antibiotic resistance, and ex vivo inhibition of each other. To investigate the possible existence of coadaptation between midgut bacteria and their host, we fed Ae. aegypti cohorts with gut bacteria from human, a frog, and two mosquito species and followed the bacterial population growth over time. The dynamics of the different species suggests coadaptation between host and bacteria, and interestingly, we found that Pantoea stewartii isolated from Ae. aegypti survive better in Ae. aegypti as compared to P. stewartii isolated from the malaria mosquito Anopheles gambiae. PMID:22283178

  17. Dispersal of Engineered Male Aedes aegypti Mosquitoes.

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    Peter Winskill

    2015-11-01

    Full Text Available Aedes aegypti, the principal vector of dengue fever, have been genetically engineered for use in a sterile insect control programme. To improve our understanding of the dispersal ecology of mosquitoes and to inform appropriate release strategies of 'genetically sterile' male Aedes aegypti detailed knowledge of the dispersal ability of the released insects is needed.The dispersal ability of released 'genetically sterile' male Aedes aegypti at a field site in Brazil has been estimated. Dispersal kernels embedded within a generalized linear model framework were used to analyse data collected from three large scale mark release recapture studies. The methodology has been applied to previously published dispersal data to compare the dispersal ability of 'genetically sterile' male Aedes aegypti in contrasting environments. We parameterised dispersal kernels and estimated the mean distance travelled for insects in Brazil: 52.8 m (95% CI: 49.9 m, 56.8 m and Malaysia: 58.0 m (95% CI: 51.1 m, 71.0 m.Our results provide specific, detailed estimates of the dispersal characteristics of released 'genetically sterile' male Aedes aegypti in the field. The comparative analysis indicates that despite differing environments and recapture rates, key features of the insects' dispersal kernels are conserved across the two studies. The results can be used to inform both risk assessments and release programmes using 'genetically sterile' male Aedes aegypti.

  18. Workbook on Identification of Aedes Aegypti Larvae.

    Science.gov (United States)

    Pratt, Harry D.; And Others

    This self-instructional booklet is designed to enable yellow fever control workers to identify the larvae of "Aedes aegypti." The morphological features of mosquito larvae are illustrated in this partially programed text, and the distinguishing features of "A. aegypti" indicated. A glossary is included. (AL)

  19. Thiosemicarbazones as Aedes aegypti larvicidal.

    Science.gov (United States)

    da Silva, João Bosco P; Navarro, Daniela Maria do A F; da Silva, Aluizio G; Santos, Geanne K N; Dutra, Kamilla A; Moreira, Diogo Rodrigo; Ramos, Mozart N; Espíndola, José Wanderlan P; de Oliveira, Ana Daura T; Brondani, Dalci José; Leite, Ana Cristina L; Hernandes, Marcelo Zaldini; Pereira, Valéria R A; da Rocha, Lucas F; de Castro, Maria Carolina A B; de Oliveira, Beatriz C; Lan, Que; Merz, Kenneth M

    2015-07-15

    A set of aryl- and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologically evaluated against the larvae of Aedes aegypti (A. aegypti), the vector responsible for diseases like Dengue and Yellow Fever. (Q)SAR studies were useful for predicting the activities of the compounds not included to create the QSAR model as well as to predict the features of a new compound with improved activity. Docking studies corroborated experimental evidence of AeSCP-2 as a potential target able to explain the larvicidal properties of its compounds. The trend observed between the in silico Docking scores and the in vitro pLC50 (equals -log LC50, at molar concentration) data indicated that the highest larvicidal compounds, or the compounds with the highest values for pLC50, are usually those with the higher docking scores (i.e., greater in silico affinity for the AeSCP-2 target). Determination of cytotoxicity for these compounds in mammal cells demonstrated that the top larvicide compounds are non-toxic.

  20. Thiosemicarbazones as Aedes aegypti larvicidal.

    Science.gov (United States)

    da Silva, João Bosco P; Navarro, Daniela Maria do A F; da Silva, Aluizio G; Santos, Geanne K N; Dutra, Kamilla A; Moreira, Diogo Rodrigo; Ramos, Mozart N; Espíndola, José Wanderlan P; de Oliveira, Ana Daura T; Brondani, Dalci José; Leite, Ana Cristina L; Hernandes, Marcelo Zaldini; Pereira, Valéria R A; da Rocha, Lucas F; de Castro, Maria Carolina A B; de Oliveira, Beatriz C; Lan, Que; Merz, Kenneth M

    2015-07-15

    A set of aryl- and phenoxymethyl-(thio)semicarbazones were synthetized, characterized and biologically evaluated against the larvae of Aedes aegypti (A. aegypti), the vector responsible for diseases like Dengue and Yellow Fever. (Q)SAR studies were useful for predicting the activities of the compounds not included to create the QSAR model as well as to predict the features of a new compound with improved activity. Docking studies corroborated experimental evidence of AeSCP-2 as a potential target able to explain the larvicidal properties of its compounds. The trend observed between the in silico Docking scores and the in vitro pLC50 (equals -log LC50, at molar concentration) data indicated that the highest larvicidal compounds, or the compounds with the highest values for pLC50, are usually those with the higher docking scores (i.e., greater in silico affinity for the AeSCP-2 target). Determination of cytotoxicity for these compounds in mammal cells demonstrated that the top larvicide compounds are non-toxic. PMID:26087027

  1. The influence of diet on the use of near-infrared spectroscopy to determine the age of female Aedes aegypti mosquitoes

    Science.gov (United States)

    Interventions targeting adult mosquitoes are used to combat transmission of vector-borne diseases, including dengue. Without available vaccines, targeting the primary vector, Aedes aegypti, is essential to prevent transmission. Older mosquitoes (>/='7 days) are of greatest epidemiological significan...

  2. Behavioral responses of two dengue virus vectors, Aedes aegypti and Aedes albopictus (Diptera: Culicidae), to DUET TM and its components

    Science.gov (United States)

    Ultralow volume (ULV) droplets of DUET TM, prallethrin and sumithrin at a sublethal dose were applied to unfed (non bloodfed) and bloodfed female Aedes aegypti Linn. and Aedes albopictus (Skuse) in a wind tunnel. Control spray droplets only contained inactive ingredients. Individual mosquitoes wer...

  3. Analysis of ovary-specific genes in relation to egg maturation and female nutritional condition in the mosquitoes Georgecraigius atropalpus and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Telang, Aparna; Rechel, Julie A; Brandt, Jessica R; Donnell, David M

    2013-03-01

    Analysis of the reproductive physiology of anautogenous mosquitoes at the molecular level is complicated by the simultaneity of ovarian maturation and the digestion of a blood meal. In contrast to anautogenous mosquitoes, autogenous female mosquitoes can acquire greater nutrient stores as larvae and exhibit higher ovarian production of ecdysteroids at adult eclosion. These features essentially replace the role of a blood meal in provisioning the first batch of eggs and initiating egg development. To gain insight into the process of ovary maturation we first performed a transcript analysis of the obligatory autogenous mosquito Georgecraigius atropalpus (formerly Ochlerotatus atropalpus). We identified ESTs using suppressive subtractive hybridization (SSH) of transcripts from ovaries at critical times during oogenesis in the absence of blood digestion. Preliminary expression studies of genes such as apolipophorin III (APO) and oxysterol binding protein (OSBP) suggested these genes might be cued to female nutritional status. We then applied our findings to the medically important anautogenous mosquito Aedes aegypti. RNAi-based analyses of these genes in Ae. aegypti revealed a reduction in APO transcripts leads to reduced lipid levels in carcass and ovaries and that OSBP may play a role in overall lipid and sterol homeostasis. In addition to expanding our understanding of mosquito ovarian development, the continued use of a comparative approach between autogenous and anautogenous species may provide novel intervention points for the regulation of mosquito egg production.

  4. Identification of germline transcriptional regulatory elements in Aedes aegypti

    Science.gov (United States)

    Akbari, Omar S.; Papathanos, Philippos A.; Sandler, Jeremy E.; Kennedy, Katie; Hay, Bruce A.

    2014-02-01

    The mosquito Aedes aegypti is the principal vector for the yellow fever and dengue viruses, and is also responsible for recent outbreaks of the alphavirus chikungunya. Vector control strategies utilizing engineered gene drive systems are being developed as a means of replacing wild, pathogen transmitting mosquitoes with individuals refractory to disease transmission, or bringing about population suppression. Several of these systems, including Medea, UDMEL, and site-specific nucleases, which can be used to drive genes into populations or bring about population suppression, utilize transcriptional regulatory elements that drive germline-specific expression. Here we report the identification of multiple regulatory elements able to drive gene expression specifically in the female germline, or in the male and female germline, in the mosquito Aedes aegypti. These elements can also be used as tools with which to probe the roles of specific genes in germline function and in the early embryo, through overexpression or RNA interference.

  5. Blood-feeding and immunogenic aedes aegypti saliva proteins

    OpenAIRE

    Surasombatpattana, Pornapat; Wasinpiyamongkol, L.; Patramool, Sirilaksana; Luplertlop, N.; Doucouré, Souleymane; Mouchet, François; Seveno, M.; Remoué, Franck; Demettre, E.; Brizard, Jean-Paul; Jouin, P.; Biron, D.G; F. Thomas; Missé, Dorothée

    2010-01-01

    Mosquito-transmitted pathogens pass through the insect's midgut (MG) and salivary gland (SG). What occurs in these organs in response to a blood meal is poorly understood, but identifying the physiological differences between sugar-fed and blood-fed (BF) mosquitoes could shed light on factors important in pathogens transmission. We compared differential protein expression in the MGs and SGs of female Aedes aegypti mosquitoes after a sugar- or blood-based diet. No difference was observed in th...

  6. Gravid females of the mosquito Aedes aegypti avoid oviposition on m-cresol in the presence of the deterrent isomer p-cresol

    OpenAIRE

    Afify, Ali; Galizia, Giovanni

    2014-01-01

    Background p-cresol (4-methylphenol) and its isomer m-cresol (3-methylphenol) have been shown to activate the same sensilla in Aedes aegypti (Linnaeus) mosquitoes. Whereas p-cresol has been suggested to play a role in oviposition site choice, the behavioral significance of m-cresol is unknown. Methods Here, we assayed the oviposition behavior of Aedes aegypti towards p-cresol and m-cresol using cage assay. Specifically we tested different concentrations of p-cresol (10-12-103 ppm) and m-creso...

  7. Mosquito traps designed to capture Aedes aegypti (Diptera: Culicidae females: preliminary comparison of Adultrap, MosquiTRAP and backpack aspirator efficiency in a dengue-endemic area of Brazil

    Directory of Open Access Journals (Sweden)

    Rafael Maciel-de-Freitas

    2008-09-01

    Full Text Available In this report, the efficiency of Adultrap under field conditions is compared to a CDC backpack aspirator and to MosquiTRAP. An urban dengue-endemic area of Rio de Janeiro was selected to evaluate the efficiency of mosquito traps in capturing Aedes aegypti females. Adultrap and aspirator captured similar numbers of Ae. aegypti females, with the former showing high specificity to gravid individuals (93.6%. A subsequent mark-release-recapture experiment was conducted to evaluate Adultrap and MosquiTRAP efficiency concomitantly. With a 6.34% recapture rate, MosquiTRAP captured a higher mean number of female Ae. aegypti per trap than Adultrap (Ç2 = 14.26; df = 1; p < 0,05. However, some MosquiTRAPs (28.12% contained immature Ae. aegypti after 18 days of exposure in the field and could be pointed as an oviposition site for female mosquitoes. Both trapping methods, designed to collect gravid Ae. aegypti females, seem to be efficient, reliable and may aid routine Ae. aegypti surveillance.

  8. Temporal genetic stability of Stegomyia aegypti (= Aedes aegypti) populations.

    Science.gov (United States)

    Gloria-Soria, A; Kellner, D A; Brown, J E; Gonzalez-Acosta, C; Kamgang, B; Lutwama, J; Powell, J R

    2016-06-01

    The mosquito Stegomyia aegypti (= Aedes aegypti) (Diptera: Culicidae) is the primary vector of viruses that cause yellow fever, dengue and Chikungunya fever. In the absence of effective vaccines, the reduction of these diseases relies on vector control strategies. The success of these strategies is tightly linked to the population dynamics of target populations. In the present study, 14 collections from St. aegypti populations separated by periods of 1-13 years were analysed to determine their temporal genetic stability. Although temporal structure is discernible in most populations, the degree of temporal differentiation is dependent on the population and does not obscure the geographic structure of the various populations. The results suggest that performing detailed studies in the years prior to and after population reduction- or modification-based control interventions at each target field site may be useful in assessing the probability of success. PMID:26744174

  9. Aedes aegypti resistance to temephos in Argentina

    OpenAIRE

    Seccacini, Emilia; Lucía Mulas, Alejandro; Eduardo N Zerba; Licastro, Susana; Masuh, Hector M.

    2008-01-01

    Monitoring of resistance of Aedes aegypti to temephos was implemented in the provinces of Formosa and Misiones, Argentina, as a response to the need to improve the vigilance for the dengue vector in areas of high risk of dengue. Eggs collected in each locality were reared, and susceptibility to temephos was assayed using larval bioassays. A weak decrease in susceptibility of larvae to temephos was observed in Clorinda and Puerto Iguazú, indicating an incipient resistance with a resistance rat...

  10. Diversidade de criadouros e tipos de imóveis freqüentados por Aedes albopictus e Aedes aegypti Diversity of oviposition containers and buildings where Aedes albopictus and Aedes aegypti can be found

    Directory of Open Access Journals (Sweden)

    Vanderlei C da Silva

    2006-12-01

    Full Text Available OBJETIVOS: Verificar a diversidade de criadouros e tipos de imóveis freqüentados por fêmeas de Aedes albopictus e Aedes aegypti. MÉTODOS: O estudo foi realizado nos anos de 2002 e 2003 no bairro de Campo Grande, Rio de Janeiro, RJ. Realizou-se pesquisa larvária em diferentes tipos de imóveis. As larvas encontradas foram identificadas em laboratório. A freqüência de larvas dessas duas espécies foi computada nos diversos criadouros disponíveis. Foram calculados os índices de infestação predial e de Breteau, as diferenças foram testadas pelo qui-quadrado. RESULTADOS: Os tipos de imóveis positivos para os aedinos foram: residências (83,9% do total; igrejas, escolas, clubes (6,8%; terrenos baldios (6,4%; e comércios (2,8%. Das 9.153 larvas, 12,0% eram de Aedes albopictus e 88,0% de Aedes aegypti. Para aquela espécie, os recipientes onde foram mais encontradas foram ralos (25,4%, latas, garrafas, vasilhames (23,9% e vasos com plantas (16,2%. Aedes aegypti mostrou-se mais freqüente nos criadouros que Aedes albopictus (chi2=145,067, pOBJECTIVE: To assess the diversity of oviposition containers and buildings where females of Aedes albopictus and Aedes aegypti can be found. METHODS: A study was carried out in the city of Rio de Janeiro, Southern Brazil, between 2002 and 2003. Larvae in different types of buildings were investigated, and immature forms found were then sent to the laboratory for identification. The larval frequency for both mosquitoes was estimated in the oviposition containers available. The Breteau index and the building infestation index were calculated and differences were tested using the Chi-square test. RESULTS: The types of buildings that were positive for Aedes albopictus and Aedes aegypti were: dwellings (83.9%; churches, schools, clubs (6.8%; vacant land (6.4%; and businesses (2.8%. Of 9,153 larvae collected, 12.0% were Aedes albopictus and 88.0% were Aedes aegypti. Aedes albopictus were mostly found in drains

  11. Nepenthes ampullaria (Nepenthaceae) Pitchers Are Unattractive to Gravid Aedes aegypti and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Chou, Lee Yiung; Dykes, Gary A; Wilson, Robyn F; Clarke, Charles M

    2016-02-01

    Nepenthes pitcher plants are colonized by a variety of specialized arthropods. As Aedes mosquitoes are container breeders, Nepenthes pitchers are a potential candidate oviposition site for vector species, such as Aedes aegypti (L.) and Aedes albopictus (Skuse). However, Aedes spp. are not commonly encountered in Nepenthes pitchers, and the environment inside the pitchers of some species is lethal to them. One exception is Nepenthes ampullaria Jack, whose pitchers are known to be colonized by Ae. albopictus on very rare occasions. Given that Ae. albopictus larvae can survive in N. ampullaria pitcher fluids, we sought to determine why pitcher colonization is rare, testing the hypothesis that gravid Aedes mosquitoes are deterred from ovipositing into container habitats that have similar characteristics to N. ampullaria pitchers. Using plastic ovitraps of different sizes, colors, and with different types of fluids (based on the characteristics of N. ampullaria pitchers), we compared oviposition rates by Aedes mosquitoes in urban and rural areas within the geographical range of N. ampullaria near Kuala Lumpur, Malaysia. Ovitraps that were black and large (>250-ml capacity) accumulated significantly more eggs than ovitraps that were smaller, or green in color. In terms of size and color, small, green ovitraps are analogous to N. ampullaria pitchers, indicating that these pitchers are not particularly attractive to gravid Ae. albopictus. Although Aedes spp. are capable of colonizing N. ampullaria pitchers, the pitchers are relatively unattractive to gravid females and do not represent a significant habitat for larvae of dengue vectors at present. PMID:26518035

  12. Early trypsin, a female-specific midgut protease in Aedes aegypti: isolation, aminoterminal sequence determination, and cloning and sequencing of the gene.

    Science.gov (United States)

    Noriega, F G; Wang, X Y; Pennington, J E; Barillas-Mury, C V; Wells, M A

    1996-02-01

    Early trypsin is a female-specific protease present in the Aedes aegypti midgut during the first hours after ingestion of a blood meal. It plays an essential role in the transcriptional activation of the late trypsin form, the major midgut endoprotease involved in the blood meal digestion. Early trypsin is the most abundant midgut polypeptide isolated by benzamidine-sepharose affinity chromatography 3 h after feeding. The amino-terminal sequence of the early trypsin protein matches that of the 3a1 cDNA for a putative trypsinogen described by Kalhok et al. (Insect. Molec. Biol., 2, 71-79, 1993). The early trypsin cDNA was over expressed in Escherichia coli. Polyclonal antibodies generated against this recombinant protein were used to show that the enzyme was present in the midgut during the first 4 h after feeding. A 2.5 kb genomic clone of the early trypsin was isolated, mapped and subcloned. A 1.56 kb subclone, corresponding to 1303 bp of the upstream regulatory region and 265 bp of the coding region, was sequenced. The gene contains a 64 nucleotide intron which interrupts the codon for Val at position 18 of the protein. This Val is located toward the end of the putative signal sequence of the protein. PMID:8882654

  13. Genome engineering and gene drive in the mosquito aedes aegypti

    OpenAIRE

    St John, Oliver Tudor Lockhart; Sinkins, Steven; Alphey, Luke

    2012-01-01

    Genetic control strategies are a novel method for reducing populations of pest insects such as the yellow fever mosquito Aedes aegypti, a major vector of several important arboviral diseases. This thesis describes efforts to develop new tools to engineer the Ae. aegypti genome and to better understand existing tools, and furthermore to use these to engineer a gene drive system in Ae. aegypti. The piggyBac transposon was found to be extremely stable in the germline of Ae. aegypti, and transpos...

  14. Aedes aegypti resistance to temephos in Argentina.

    Science.gov (United States)

    Seccacini, Emilia; Lucia, Alejandro; Zerba, Eduardo; Licastro, Susana; Masuh, Hector

    2008-12-01

    Monitoring of resistance of Aedes aegypti to temephos was implemented in the provinces of Formosa and Misiones, Argentina, as a response to the need to improve the vigilance for the dengue vector in areas of high risk of dengue. Eggs collected in each locality were reared, and susceptibility to temephos was assayed using larval bioassays. A weak decrease in susceptibility of larvae to temephos was observed in Clorinda and Puerto Iguazú, indicating an incipient resistance with a resistance ratio of 3. No control failures have been observed yet, and this program should allow the early detection of a real problem in our country.

  15. Dengue virus-infected Aedes aegypti in the home environment.

    Science.gov (United States)

    Garcia-Rejon, Julian; Loroño-Pino, Maria Alba; Farfan-Ale, Jose Arturo; Flores-Flores, Luis; Del Pilar Rosado-Paredes, Elsy; Rivero-Cardenas, Nubia; Najera-Vazquez, Rosario; Gomez-Carro, Salvador; Lira-Zumbardo, Victor; Gonzalez-Martinez, Pedro; Lozano-Fuentes, Saul; Elizondo-Quiroga, Darwin; Beaty, Barry J; Eisen, Lars

    2008-12-01

    We determined abundance of Aedes aegypti mosquitoes and presence of dengue virus (DENV) in females collected from premises of laboratory-confirmed dengue patients over a 12-month period (March 2007 to February 2008) in Merida, Mexico. Backpack aspiration from 880 premises produced 1,836 females and 1,292 males indoors (predominantly from bedrooms) and 102 females and 108 males from patios/backyards. The mean weekly indoor catch rate per home peaked at 7.8 females in late August. Outdoor abundances of larvae or pupae were not predictive of female abundance inside the home. DENV-infected Ae. aegypti females were recovered from 34 premises. Collection of DENV-infected females from homes of dengue patients up to 27 days after the onset of symptoms (median, 14 days) shows the usefulness of indoor insecticide application in homes of suspected dengue patients to prevent their homes from becoming sources for dispersal of DENV by persons visiting and being bitten by infected mosquitoes. PMID:19052309

  16. Behavioral Response of Aedes aegypti Mosquito towards Essential Oils Using Olfactometer

    OpenAIRE

    Ashish Uniyal; Tikar, Sachin N.; Mendki, Murlidhar J.; Ram Singh; Shukla, Shakti V; Om P Agrawal; Vijay Veer; Devanathan Sukumaran

    2016-01-01

    Background: Aedes aegypti mosquito is responsible for transmitting human diseases like dengue and chikungunya. Personal or space protection with insect repellents is a practical approach to reducing human mosquito contact, thereby minimizing disease transmission. Essential oils are natural volatile substances from plants used as protective measure against blood-sucking mosquitoes.Methods: Twenty-three essential oils were evaluated for their repellent effect against Ae. aegypti female mosquito...

  17. Evaluation of Sumithion L-40 against Aedes aegypti (L.) and Aedes albopictus Skuse.

    Science.gov (United States)

    Loke, S R; Sing, K W; Teoh, G N; Lee, H L

    2015-03-01

    Space spraying of chemical insecticides is still an important mean of controlling Aedes mosquitoes and dengue transmission. For this purpose, the bioefficacy of space-sprayed chemical insecticide should be evaluated from time to time. A simulation field trial was conducted outdoor in an open field and indoor in unoccupied flat units in Kuala Lumpur, to evaluate the adulticidal and larvicidal effects of Sumithion L-40, a ULV formulation of fenitrothion. A thermal fogger with a discharge rate of 240 ml/min was used to disperse Sumithion L-40 at 3 different dosages (350 ml/ha, 500 ml/ha, 750 ml/ha) against lab-bred larvae and adult female Aedes aegypti and Aedes albopictus. An average of more than 80% adult mortality was achieved for outdoor space spray, and 100% adult mortality for indoor space spray, in all tested dosages. Outdoor larvicidal effect was noted up to 14 days and 7 days at a dosage of 500 and 750 ml/ha for Ae. aegypti and Ae. albopictus, respectively. Indoor larvicidal effect was up to 21 days (500 ml/ha) and 14 days (750 ml/ha), respectively, after spraying with larval mortality > 50% against Ae. aegypti. This study concluded that the effective dosage of Sumithion L-40 thermally applied against adult Ae. aegypti and Ae. albopictus indoor and outdoor is 500 and 750 ml/ha. Based on these dosages, effective indoor spray volume is 0.4 - 0.6 ml/m³. Additional indoor and outdoor larvicidal effect will be observed at these application dosages, in addition to adult mortality.

  18. Characterising the spatial dynamics of sympatric Aedes aegypti and Aedes albopictus populations in the Philippines

    Directory of Open Access Journals (Sweden)

    Jennifer Duncombe

    2013-11-01

    Full Text Available Entomological surveillance and control are essential to the management of dengue fever (DF. Hence, understanding the spatial and temporal patterns of DF vectors, Aedes (Stegomyia aegypti (L. and Ae. (Stegomyia albopictus (Skuse, is paramount. In the Philippines, resources are limited and entomological surveillance and control are generally commenced during epidemics, when transmission is difficult to control. Recent improvements in spatial epidemiological tools and methods offer opportunities to explore more efficient DF surveillance and control solutions: however, there are few examples in the literature from resource-poor settings. The objectives of this study were to: (i explore spatial patterns of Aedes populations and (ii predict areas of high and low vector density to inform DF control in San Jose village, Muntinlupa city, Philippines. Fortnightly, adult female Aedes mosquitoes were collected from 50 double-sticky ovitraps (SOs located in San Jose village for the period June-November 2011. Spatial clustering analysis was performed to identify high and low density clusters of Ae. aegypti and Ae. albopictus mosquitoes. Spatial autocorrelation was assessed by examination of semivariograms, and ordinary kriging was undertaken to create a smoothed surface of predicted vector density in the study area. Our results show that both Ae. aegypti and Ae. albopictus were present in San Jose village during the study period. However, one Aedes species was dominant in a given geographic area at a time, suggesting differing habitat preferences and interspecies competition between vectors. Density maps provide information to direct entomological control activities and advocate the development of geographically enhanced surveillance and control systems to improve DF management in the Philippines.

  19. Free flight of the mosquito Aedes aegypti

    CERN Document Server

    Iams, S M

    2012-01-01

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

  20. Role of Aedes aegypti and Aedes albopictus during the 2011 dengue fever epidemics in Hanoi, Vietnam

    Institute of Scientific and Technical Information of China (English)

    Pham; Thi; Kim; Lien; Vu; Trong; Duoc; Laurent; Gavotte; Emmanuel; Cornillot; Phan; Thi; Nga; Laurence; Briant; Roger; Frutos; Tran; Nhu; Duong

    2015-01-01

    Objective: To record the human cases of dengue fever(DF) and investigate the Aedes mosquito species circulating during the Hanoi 2011 DF epidemics. Methods: 24 different outbreak points were recorded in 8 districts between August and December 2011. Results: 140 patients were hospitalized following dengue diagnostic with a predominance of males(59.3%) and the 15-34 age class. Only DENV-1(11.27%) and DENV-2(88.73%) serotypes were detected in human samples. Mosquito sampling performed in and around patients households revealed the predominance of Aedes aegypti(95.15%) versus Aedes albopictus(4.85%). There is a positive correlation between the population density of Aedes aegypti and the number of human cases and duration of outbreaks. Conclusions: This was not observed for Aedes albopictus. 3 pools of Aedes aegypti were positive with dengue virus, two with DENV-1 and one with DENV-2.

  1. Periodicidade de oviposição de fêmeas de Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae em laboratório e campo Periodicity of oviposition of females of Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae in laboratory and field

    Directory of Open Access Journals (Sweden)

    Adriana dos Santos Gomes

    2006-08-01

    Full Text Available O objetivo deste trabalho foi determinar o padrão gonotrófico de fêmeas de Aedes aegypti em condições de laboratório e de campo. Fêmeas copuladas e alimentadas com sangue de galinha foram transferidas para gaiolas de polipropileno e oferecidos diferentes substratos de oviposição (papel sulfite, filtro, manteiga e toalha. O papel filtro recebeu significativamente maior (40,4% deposição de ovos do que os demais substratos. Observou-se que maior (35,7% dia modal oviposição ocorreu ao terceiro dia, após alimentação sangüínea. Foi observada a oviposição das fêmeas a cada duas horas de intervalo, durante o fotoperíodo em laboratório e em campo por meio de ovitrampas. Os resultados de laboratório demonstraram que maior deposição de ovos ocorreu entre a 9ª - 12ª hora da fotofase e 1ª - 2ª hora de escotofase. Em campo maior número de ovos ocorreu entre 9ª - 12ª hora de fotofase e na 1ª - 4ª hora de escotofase. Estes resultados indicam que Aedes aegypti exibiu um padrão na periodicidade de oviposição e podem subsidiar em programas de monitoramento e ou controle do inseto vetor. Sugere-se que, em campo, por exemplo, armadilhas de oviposição (ovitrampa devem ser instaladas no período da manhã pois as capturas ocorrem a partir do período da tarde.The object of this work was to determine of gonotrophic diel pattern of female Aedes aegypti in laboratory and field conditions. Three day-old female mosquitoes were the fed on chicken blood and transferred to bioassay cages. Four oviposition substrates were offered: paper sulfite, filter, butter and towel. The results showed that filter paper received a significantly higher (40.4% percentage of deposited eggs than the other oviposition substrates. After their first blood meal, females started to oviposit on the 3rd model day; 35.7% of the total number of eggs deposited. The oviposition diel patterns of females were observed every two hours during the photoperiod in the

  2. Detection of Aedes aegypti, Aedes albopictus, and Aedes koreicus in the Area of Sochi, Russia.

    Science.gov (United States)

    Ganushkina, Ludmila A; Patraman, Ivan V; Rezza, Giovanni; Migliorini, Luigi; Litvinov, Serguei K; Sergiev, Vladimir P

    2016-01-01

    Following the identification of Aedes (Ae.) aegypti in the Sochi area in Russia at the beginning of 2000, entomological surveys were conducted during the summers of 2007, 2011, and 2012, leading to the identification of Ae. albopictus and Ae. koreicus. These findings highlight Russia as being the only country in the World Health Organization European Region with a documented presence of both Ae. aegypti and Ae. albopictus mosquitoes. Both mosquito species are found on the coasts of the Black Sea. Control measures are needed to reduce the possible risks of importing exotic vector-borne infections, such as dengue and chikungunya.

  3. Multiple factors contribute to anautogenous reproduction by the mosquito Aedes aegypti.

    Science.gov (United States)

    Gulia-Nuss, Monika; Elliot, Anne; Brown, Mark R; Strand, Michael R

    2015-11-01

    Aedes aegypti is an anautogenous mosquito that must blood feed on a vertebrate host to produce and lay a clutch of eggs. The rockpool mosquito, Georgecraigius atropalpus, is related to A. aegypti but is a facultatively autogenous species that produces its first clutch of eggs shortly after emerging without blood feeding. Consumption of a blood meal by A. aegypti triggers the release of ovary ecdysteroidogenic hormone (OEH) and insulin-like peptide 3 (ILP3) from the brain, which stimulate egg formation. OEH and ILP3 also stimulate egg formation in G. atropalpus but are released at eclosion independently of blood feeding. These results collectively suggest that blood meal dependent release of OEH and ILP3 is one factor that prevents A. aegypti from reproducing autogenously. Here, we examined two other factors that potentially inhibit autogeny in A. aegypti: teneral nutrient reserves and the ability of OEH and ILP3 to stimulate egg formation in the absence of blood feeding. Measures of nutrient reserves showed that newly emerged A. aegypti females had similar wet weights but significantly lower protein and glycogen reserves than G. atropalpus females when larvae were reared under identical conditions. OEH stimulated non-blood fed A. aegypti females to produce ecdysteroid hormone and package yolk into oocytes more strongly than ILP3. OEH also reduced host seeking and blood feeding behavior, yet females produced few mature eggs. Overall, our results indicate that multiple factors prevent A. aegypti from reproducing autogenously. PMID:26255841

  4. A RE-SURVEY OF AEDES AEGYPTI AND AEDES ALBOPICTUS IN SABAH, MALAYSIA

    OpenAIRE

    Feffrey Hii Lu King

    2012-01-01

    Di Sabah, Malaysia telah diadakan survey nyamuk Aedes aegypti dan Aedes albopictus dari bulan Agustus s/d September 1974 dan Maret-April 1975. Survey dilakukan pada 5 daerah di Kudat. Pantai Barat, Pedalaman Sandahan danTawan dengan tujuan untuk melihat distribusi dan density dari kedua jenis nyamuk tsb. Hasil survey menunjukkan bahwa nyamuk A. aegypti telah menyebar pada hampir seluruh daerah pantai Sabah, dan ditemukan hampir pada sebagian besar kotal dan daerah pedesaan di banyak desa. Di ...

  5. Bioefficacy of crude extract of Cyperus aromaticus (Family:Cyperaceae) cultured cells, against Aedes aegypti and Aedes albopictus mosquitoes

    Institute of Scientific and Technical Information of China (English)

    Fatemeh Kamiabi; Zairi Jaal; Chan Lai Keng

    2013-01-01

    Objective:To evaluate the growth inhibition activity of the crude extract of Cyperus aromaticus (C. aromaticus) cultured cells against the 3rd instar larvae of Aedes aegypti (Linn.) and Aedes albopictus Skuse (Ae. albopictus) under laboratory conditions, and determine the sublethal effects (EI50) of the crude extract of C. aromaticus cultured cells on some biological and morphological parameters of both Aedes mosquito species during two generations as well. Methods:The cell suspension cultures of C. aromaticus were activated from five callus lines (P4, Pa, Z1, Z6 and Ml) derived from the root explants of in vitro plantlets. The cultured cells were extracted in chloroform and used as plant material for the present study. For detection of juvenile hormone III, the crude extracts were analyzed by HPLC. Then the crude extracts of the three C. aromaticus cultured cell lines which contained varied amounts of juvenile hormone III [high level (P4 cell line), medium level (Z1 cell line) and low level (Ml cell line)] were tested against Aedes mosquito species. Laboratory evaluation was performed against late third instar larvae of the Vector Control Research Unit strains of Ae. aegypti and Ae. albopictus using the standard WHO method. The effects of EI50 of the C. aromaticus cultured P4 cells on fecundity, fertility, growth period, sex ratio, adult size and longevity of Aedes mosquitoes were assessed. Results:Bioassay tests presented the remarkable growth inhibition activity of the crude extracts of C. aromaticus cultured cells against the two Aedes mosquitoes. Between the two mosquito species, Ae. albopictus was more susceptible to the crude extracts with lower EI50 values. EI50 of the crude extract of C. aromaticus cultured cells (P4) increased the sterility indices in the parental generation females in both Aedes mosquito species. A significant delay in the pupal formation and adult emergence were observed in the parental generation of the both mosquito species. The sex

  6. Mathematical model of temephos resistance in Aedes aegypti mosquito population

    Science.gov (United States)

    Aldila, D.; Nuraini, N.; Soewono, E.; Supriatna, A. K.

    2014-03-01

    Aedes aegypti is the main vector of dengue disease in many tropical and sub-tropical countries. Dengue became major public concern in these countries due to the unavailability of vaccine or drugs for dengue disease in the market. Hence, the only way to control the spread of DF and DHF is by controlling the vectors carrying the disease, for instance with fumigation, temephos or genetic manipulation. Many previous studies conclude that Aedes aegypti may develop resistance to many kind of insecticide, including temephos. Mathematical model for transmission of temephos resistance in Aedes aegypti population is discussed in this paper. Nontrivial equilibrium point of the system and the corresponding existence are shown analytically. The model analysis have shown epidemiological trends condition that permits the coexistence of nontrivial equilibrium is given analytically. Numerical results are given to show parameter sensitivity and some cases of worsening effect values for illustrating possible conditions in the field.

  7. Effect of temperature on the population dynamics of Aedes aegypti

    Science.gov (United States)

    Yusoff, Nuraini; Tokachil, Mohd Najir

    2015-10-01

    Aedes aegypti is one of the main vectors in the transmission of dengue fever. Its abundance may cause the spread of the disease to be more intense. In the study of its biological life cycle, temperature was found to increase the development rate of each stage of this species and thus, accelerate the process of the development from egg to adult. In this paper, a Lefkovitch matrix model will be used to study the stage-structured population dynamics of Aedes aegypti. In constructing the transition matrix, temperature will be taken into account. As a case study, temperature recorded at the Subang Meteorological Station for year 2006 until 2010 will be used. Population dynamics of Aedes aegypti at maximum, average and minimum temperature for each year will be simulated and compared. It is expected that the higher the temperature, the faster the mosquito will breed. The result will be compared to the number of dengue fever incidences to see their relationship.

  8. Stage-Structured Population Dynamics of AEDES AEGYPTI

    Science.gov (United States)

    Yusoff, Nuraini; Budin, Harun; Ismail, Salemah

    Aedes aegypti is the main vector in the transmission of dengue fever, a vector-borne disease affecting world population living in tropical and sub-tropical countries. Better understanding of the dynamics of its population growth will help in the efforts of controlling the spread of this disease. In looking at the population dynamics of Aedes aegypti, this paper explored the stage-structured modeling of the population growth of the mosquito using the matrix population model. The life cycle of the mosquito was divided into five stages: eggs, larvae, pupae, adult1 and adult2. Developmental rates were obtained for the average Malaysian temperature and these were used in constructing the transition matrix for the matrix model. The model, which was based only on temperature, projected that the population of Aedes aegypti will blow up with time, which is not realistic. For further work, other factors need to be taken into account to obtain a more realistic result.

  9. Utilization of Blood fed Females of Aedes aegypti as a Vehicle for the Transfer of the Insect Growth Regulator, Pyriproxyfen, to Larval Habitats

    OpenAIRE

    Itoh, Takaaki

    1995-01-01

    Bloodfed females of Ae. aegypti were exposed to a surface treated with pyriproxyfen at 1.0g/m^2 for 30 min and then allowed to lay eggs in cups of water containing 4th instar larvae in a cage. Adult emergence from the immatures was highly inhibited, and transmission of pyriproxyfen from the females to the water was revealed. The transfer of the chemicals to the water decreased with time before the blood meal. Chemical analysis for pyriproxyfen on the exoskeleton of treated females demonstrate...

  10. Changing domesticity of Aedes aegypti in northern peninsular Malaysia: reproductive consequences and potential epidemiological implications.

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    Rahman G M Saifur

    Full Text Available BACKGROUND: The domestic dengue vector Aedes aegypti mosquitoes breed in indoor containers. However, in northern peninsular Malaysia, they show equal preference for breeding in both indoor and outdoor habitats. To evaluate the epidemiological implications of this peridomestic adaptation, we examined whether Ae. aegypti exhibits decreased survival, gonotrophic activity, and fecundity due to lack of host availability and the changing breeding behavior. METHODOLOGY/PRINCIPAL FINDINGS: This yearlong field surveillance identified Ae. aegypti breeding in outdoor containers on an enormous scale. Through a sequence of experiments incorporating outdoors and indoors adapting as well as adapted populations, we observed that indoors provided better environment for the survival of Ae. aegypti and the observed death patterns could be explained on the basis of a difference in body size. The duration of gonotrophic period was much shorter in large-bodied females. Fecundity tended to be greater in indoor acclimated females. We also found increased tendency to multiple feeding in outdoors adapted females, which were smaller in size compared to their outdoors breeding counterparts. CONCLUSION/SIGNIFICANCE: The data presented here suggest that acclimatization of Ae. aegypti to the outdoor environment may not decrease its lifespan or gonotrophic activity but rather increase breeding opportunities (increased number of discarded containers outdoors, the rate of larval development, but small body sizes at emergence. Size is likely to be correlated with disease transmission. In general, small size in Aedes females will favor increased blood-feeding frequency resulting in higher population sizes and disease occurrence.

  11. On the analysis of parasite effect for Aedes aegypti and Aedes albopictus population

    Science.gov (United States)

    Kallista, Meta; Aldila, Dipo; Nuraini, Nuning; Soewono, Edy

    2014-03-01

    It has been reported in some countries that the population of Aedes aegypti has been significantly reduced by the invasion of Aedes albopictus. There has been a hypothesis explaining this phenomenon of which investigated the influence of parasites pathogenesis to the competition between these two mosquito species in the fields. Ascogregarina taiwanensis and Ascogregarina culicis are known as parasites that infect Aedes albopictus and Aedes aegypti, respectively. Several studies have concluded that Ascogregarina taiwanensis caused high fatality for Aedes aegypti larvae, but Ascogregarina culicis was not pathogenic to Aedes albopictus larvae. Therefore, Ascogregarina taiwanensis may contribute to reduce the number of populations Aedes aegypti in the fields. Inspired by these facts, a mathematical model depicting interaction between parasites and mosquitoes is constructed in this paper. In this model are included six dynamic mosquito compartments, i.e. egg, larvae, infected larvae, adult, infected adult and one dynamic compartment for parasite. Derivation of the existence criteria and the stability analysis of parasite-free equilibrium as well as the basic offspring for the model are presented. Numerical simulations for sensitivity analysis indicating the invasive species for variation parameters are shown.

  12. Aedes cadherin mediates the in vivo toxicity of the Cry11Aa toxin to Aedes aegypti.

    Science.gov (United States)

    Lee, Su-Bum; Chen, Jianwu; Aimanova, Karlygash G; Gill, Sarjeet S

    2015-06-01

    Cadherin plays an important role in the toxicity of Bacillus thuringiensis Cry proteins. We previously cloned a full-length cadherin from Aedes aegypti larvae and reported this protein binds Cry11Aa toxin from B. thuringiensis subsp. israelensis with high affinity, ≈16.7nM. Based on these results, we investigated if Aedes cadherin is involved in the in vivo toxicity of Cry11Aa toxin to Ae. aegypti. We established a mosquito cell line stably expressing the full-length Aedes cadherin and transgenic mosquitoes with silenced Aedes cadherin expression. Cells expressing the Aedes cadherin showed increased sensitivity to Cry11Aa toxin. Cry11Aa toxin at 400nM killed approximately 37% of the cells in 3h. Otherwise, transgenic mosquitoes with silenced Aedes cadherin expression showed increased tolerance to Cry11Aa toxin. Furthermore, cells expressing Aedes cadherin triggered Cry11Aa oligomerization. These results show the Aedes cadherin plays a pivotal role in Cry11Aa toxicity to Ae. aegypti larvae by mediating Cry11Aa oligomerization. However, since high toxicity was not obtained in cadherin-expressing cells, an additional receptor may be needed for manifestation of full toxicity. Moreover, cells expressing Aedes cadherin were sensitive to Cry4Aa and Cry11Ba, but not Cry4Ba. However transgenic mosquitoes with silenced Aedes cadherin expression showed no tolerance to Cry4Aa, Cry4Ba, and Cry11Ba toxins. These results suggest that while Aedes cadherin may mediate Cry4Aa and Cry11Ba toxicity, this cadherin but is not the main receptor of Cry4Aa, Cry4Ba and Cry11Ba toxin in Ae. aegypti.

  13. Susceptibilidade de Aedes aegypti aos inseticidas temephos e cipermetrina, Brasil Susceptibility of Aedes aegypti to temephos and cypermethrin insecticides, Brazil

    OpenAIRE

    Jonny E Duque Luna; Marcos Ferrer Martins; Adriana Felix dos Anjos; Eduardo Fumio Kuwabara; Mário Antônio Navarro-Silva

    2004-01-01

    Realizaram-se bioensaios para detectar a susceptibilidade de Aedes aegypti aos inseticidas químicos, temefós e cipermetrina. Os resultados mostraram que esta espécie é suscetível a temefós e apresenta resistência a cipermetrinae.Bioassays were performed in order to detect the susceptibility of Aedes aegypti to the chemical insecticides temephos and cypermethrin. The results showed that this species is susceptible to temephos and presents resistance to cypermethrin.

  14. Susceptibilidade de Aedes aegypti aos inseticidas temephos e cipermetrina, Brasil Susceptibility of Aedes aegypti to temephos and cypermethrin insecticides, Brazil

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    Jonny E Duque Luna

    2004-12-01

    Full Text Available Realizaram-se bioensaios para detectar a susceptibilidade de Aedes aegypti aos inseticidas químicos, temefós e cipermetrina. Os resultados mostraram que esta espécie é suscetível a temefós e apresenta resistência a cipermetrinae.Bioassays were performed in order to detect the susceptibility of Aedes aegypti to the chemical insecticides temephos and cypermethrin. The results showed that this species is susceptible to temephos and presents resistance to cypermethrin.

  15. A review on symmetries for certain Aedes aegypti models

    Science.gov (United States)

    Freire, Igor Leite; Torrisi, Mariano

    2015-04-01

    We summarize our results related with mathematical modeling of Aedes aegypti and its Lie symmetries. Moreover, some explicit, group-invariant solutions are also shown. Weak equivalence transformations of more general reaction diffusion systems are also considered. New classes of solutions are obtained.

  16. Pyrethroid resistance is widespread among Florida populations of Aedes aegypti

    Science.gov (United States)

    Aedes aegypti is an efficient vector of a number of diseases that affect man and is of increasing concern because of the reemergence of dengue and recent identification of locally acquired chikungunya in Florida. Pesticide resistance in this species has been demonstrated in several neighboring coun...

  17. Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection

    Science.gov (United States)

    Conway, Michael J.; Londono-Renteria, Berlin; Troupin, Andrea; Watson, Alan M.; Klimstra, William B.; Fikrig, Erol; Colpitts, Tonya M.

    2016-01-01

    Aedes aegypti is the primary vector of several medically relevant arboviruses including dengue virus (DENV) types 1–4. Ae. aegypti transmits DENV by inoculating virus-infected saliva into host skin during probing and feeding. Ae. aegypti saliva contains over one hundred unique proteins and these proteins have diverse functions, including facilitating blood feeding. Previously, we showed that Ae. aegypti salivary gland extracts (SGEs) enhanced dissemination of DENV to draining lymph nodes. In contrast, HPLC-fractionation revealed that some SGE components inhibited infection. Here, we show that D7 proteins are enriched in HPLC fractions that are inhibitory to DENV infection, and that recombinant D7 protein can inhibit DENV infection in vitro and in vivo. Further, binding assays indicate that D7 protein can directly interact with DENV virions and recombinant DENV envelope protein. These data reveal a novel role for D7 proteins, which inhibits arbovirus transmission to vertebrates through a direct interaction with virions. PMID:27632170

  18. Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection.

    Science.gov (United States)

    Conway, Michael J; Londono-Renteria, Berlin; Troupin, Andrea; Watson, Alan M; Klimstra, William B; Fikrig, Erol; Colpitts, Tonya M

    2016-09-01

    Aedes aegypti is the primary vector of several medically relevant arboviruses including dengue virus (DENV) types 1-4. Ae. aegypti transmits DENV by inoculating virus-infected saliva into host skin during probing and feeding. Ae. aegypti saliva contains over one hundred unique proteins and these proteins have diverse functions, including facilitating blood feeding. Previously, we showed that Ae. aegypti salivary gland extracts (SGEs) enhanced dissemination of DENV to draining lymph nodes. In contrast, HPLC-fractionation revealed that some SGE components inhibited infection. Here, we show that D7 proteins are enriched in HPLC fractions that are inhibitory to DENV infection, and that recombinant D7 protein can inhibit DENV infection in vitro and in vivo. Further, binding assays indicate that D7 protein can directly interact with DENV virions and recombinant DENV envelope protein. These data reveal a novel role for D7 proteins, which inhibits arbovirus transmission to vertebrates through a direct interaction with virions. PMID:27632170

  19. Iron Loaded Ferritin Secretion and Inhibition by CI-976 in Aedes aegypti larval cells

    OpenAIRE

    Geiser, Dawn L.; Shen, Meng-Chieh; Mayo, Jonathan J.; Winzerling, Joy J.

    2009-01-01

    Ferritin is a multimer of 24 subunits of heavy and light chains. In mammals, iron taken into cells is stored in ferritin or incorporated into iron-containing proteins. Very little ferritin is found circulating in mammalian serum; most is retained in the cytoplasm. Female mosquitoes, such as Aedes aegypti (yellow fever mosquito, Diptera), require a blood meal for oogenesis. Mosquitoes receive a potentially toxic level of iron in the blood meal which must be processed and stored. We demonstrate...

  20. Evaluation of Bifenthrin and Acorus calamus Linn. Extract against Aedes aegypti L. and Aedes albopictus (Skuse)

    OpenAIRE

    Sulaiman, S.; DSF Abang Kamarudin; Othman, H

    2008-01-01

    Background: Bifenthrin and Acorus calamus Linn extract were evaluated against dengue vectors in the laboratory.Methods: Both Bifenthrin and Acorus calamus Linn crude hexane extract were bioassayed against the adults and larval stages of dengue vectors Aedes aegypti L. and Aedes albopictus(Skuse) in the laboratory.Results: The A. calamus crude hexane extract exhibited a larvicidal activity against 4th-instar Ae. aegypti larvae with LC50 and LC90 values of 0.4418 and 11.3935 ppm respectively. T...

  1. Bdelloid rotifer, Philodina species in the breeding containers of Aedes aegypti and Aedes albopictus.

    Science.gov (United States)

    Muniaraj, M; Arunachalam, N; Paramasivan, R; Mariappan, T; Philip Samuel, P; Rajamannar, V

    2012-12-01

    The vector mosquitoes of dengue and chikungunya fever, Aedes aegypti and Aedes albopictus have adapted to feed on humans and undergo larval and pupal development in natural and artificial freshwater collections. Although several studies reported, still, much information is required to understand the successful survival of Aedes mosquitoes in small temporary containers. In an investigation conducted in the chikungunya affected areas of Kerala state, India, the presence of Bdelloid rotifer, Philodina in 95% of breeding habitats of Ae. aegypti and Ae. albopictus was recorded. The role of Philodina in the breeding containers was investigated. It was found that while in control the number of Philodina was found increasing in the water sample during the study period of seven days, the number found decreased in the containers with larvae of Aedes. The gut content analysis also confirmed the presence of the rotating wheel, corona of Philodina in some of the specimen suggests its role as major larval food. PMID:23202612

  2. Ecological Modeling of Aedes aegypti (L.) Pupal Production in Rural Kamphaeng Phet, Thailand

    NARCIS (Netherlands)

    Aldstadt, J.; Koenraadt, C.J.M.; Fansiri, T.; Kijchalao, U.; Richardson, J.; Jones, J.W.; Scott, T.W.

    2011-01-01

    Background - Aedes aegypti (L.) is the primary vector of dengue, the most important arboviral infection globally. Until an effective vaccine is licensed and rigorously administered, Ae. aegypti control remains the principal tool in preventing and curtailing dengue transmission. Accurate predictions

  3. Chemical control of Aedes aegypti: a historical perspective

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    Alejandra Manjarres-Suarez

    2013-06-01

    Full Text Available Objective: To describe the use of chemical insecticides throughout history as the main tool to fight against Aedes aegypti, a vector of dengue virus. Methods: A text mining approach was conducted on databases, such as PUBMED and SCIENCE DIRECT, using the keywords “Aedes aegypti”, combined with the words “insecticides”, “resistance”, “organochlorines”, “organophosphates”, “carbamates” and “pyrethroids”. Results related to historical information dealing with the chemical control of Aedes aegypti, in particular those containing data on insecticide resistance for this species, were scrutinized and analyzed. Results: Different chemical groups have been utilized to control A. aegypti, including organochlorine, organophosphate, carbamate and pyrethroid insecticides. In general, the tendency has been to replace a particular pesticide, for which resistance had been detected, for a new one, mosquito-sensitive, and with little evidence of deleterious effects derived from its use. The spread of resistance has been registered in several countries of America, Asia and Africa. Two mechanisms have been highly cited to be responsible for the resistance; the increase activity of detoxifying enzymes, and structural changes in the insecticide target site, mostly within the central nervous system. Conclusion: Excessive use of chemical insecticides and the lack of dosing control have led to widespread resistance in A. aegypti, as no “safer” alternative chemical options are available for vector control in different countries, impacting human health.

  4. Comparison of the insecticide susceptibilities of laboratory strains of Aedes aegypti and Aedes albopictus

    OpenAIRE

    Andrea Gómez; Emilia Seccacini; Eduardo Zerba; Susana Licastro

    2011-01-01

    A susceptible strain of Aedes albopictus derived from the Gainesville strain (Florida, USA) was established in our laboratory. The larvicidal efficacies of the neurotoxic insecticides temephos, permethrin and the pure cis and trans-permethrin isomers and the microbial insecticide Bacillus thuringiensis israelensis (Bti) against Ae. albopictus were estimated and compared to a susceptible strain of Aedes aegypti. The larvicidal effect of insect growth regulator pyriproxyfen was also evaluated i...

  5. Insecticide susceptibility of Aedes aegypti and Aedes albopictus in Central Africa

    OpenAIRE

    Nwane Philippe; Nchoutpouen Elysée; Chandre Fabrice; Marcombe Sébastien; Kamgang Basile; Etang Josiane; Corbel Vincent; Paupy Christophe

    2011-01-01

    Abstract Background Aedes aegypti (Linnaeus, 1762) and Aedes albopictus (Skuse, 1894) are the main vectors of dengue (DENV) and chikungunya (CHIKV) viruses worldwide. As there is still no vaccine or specific treatment for DENV and CHIKV, vector control remains the cornerstone of prevention and outbreak control. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides in several areas through the world. Throughout...

  6. Dynamics of Aedes aegypti and Culex quinquefasciatus in septic tanks.

    Science.gov (United States)

    Mackay, Andrew J; Amador, Manuel; Diaz, Annette; Smith, Josh; Barrera, Roberto

    2009-12-01

    Aedes aegypti and Culex quinquefasciatus were found in large numbers emerging from septic tanks in southern Puerto Rico during the dry season. Previous studies suggested that Ae. aegypti uses subterranean aquatic habitats only during dry periods when surface containers do not have water. This research investigated whether septic tanks are alternative aquatic habitats that this mosquito uses during unfavorable times of the year, or whether Ae. aegypti uses this aquatic habitat throughout the year. To assess temporal change, exit traps were used to collect mosquitoes emerging from septic tanks in Playa/Playita, southern Puerto Rico, from November 2006 to October 2007. We also investigated the hypotheses that (1) the production of Ae. aegypti in septic tanks was larger than in surface containers and (2) adult mosquitoes emerging from septic tanks were larger than those emerging from surface containers. This study demonstrated that unsealed septic tanks produced large numbers of Ae. aegypti and Cx. quinquefasciatus throughout the year, without any significant relationship with rainfall. The number of adult Ae. aegypti emerging per day from septic tanks in each community was 3 to 9 times larger than those produced in surface containers. It was also demonstrated that Ae. aegypti emerging from septic tanks were significantly larger than those emerging from surface container habitats. It is recommended that dengue prevention programs include regular inspection and maintenance of septic tanks in communities lacking sewerage.

  7. History of domestication and spread of Aedes aegypti - A Review

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    Jeffrey R Powell

    2013-01-01

    Full Text Available The adaptation of insect vectors of human diseases to breed in human habitats (domestication is one of the most important phenomena in medical entomology. Considerable data are available on the vector mosquito Aedes aegypti in this regard and here we integrate the available information including genetics, behaviour, morphology, ecology and biogeography of the mosquito, with human history. We emphasise the tremendous amount of variation possessed by Ae. aegypti for virtually all traits considered. Typological thinking needs to be abandoned to reach a realistic and comprehensive understanding of this important vector of yellow fever, dengue and Chikungunya.

  8. The logistic model for predicting the non-gonoactive Aedes aegypti females El modelo logístico para predecir la frecuencia de hembras no gonoactivas en función del tamaño corporal y tipo de colecta, en poblaciones de Aedes aegypti, en Monterrey, México

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    Filiberto Reyes-Villanueva

    2004-06-01

    Full Text Available OBJECTIVE: To estimate, using logistic regression, the likelihood of occurrence of a non-gonoactive Aedes aegypti female, previously fed human blood, with relation to body size and collection method. MATERIAL AND METHODS: This study was conducted in Monterrey, Mexico, between 1994 and 1996. Ten samplings of 60 mosquitoes of Ae aegypti females were carried out in three dengue endemic areas: six of biting females, two of emerging mosquitoes, and two of indoor resting females. Gravid females, as well as those with blood in the gut were removed. Mosquitoes were taken to the laboratory and engorged on human blood. After 48 hours, ovaries were dissected to register whether they were gonoactive or non-gonoactive. Wing-length in mm was an indicator for body size. The logistic regression model was used to assess the likelihood of non-gonoactivity, as a binary variable, in relation to wing-length and collection method. RESULTS: Of the 600 females, 164 (27% remained non-gonoactive, with a wing-length range of 1.9-3.2 mm, almost equal to that of all females (1.8-3.3 mm. The logistic regression model showed a significant likelihood of a female remaining non-gonoactive (Y=1. The collection method did not influence the binary response, but there was an inverse relationship between non-gonoactivity and wing-length. CONCLUSIONS: Dengue vector populations from Monterrey, Mexico display a wide-range body size. Logistic regression was a useful tool to estimate the likelihood for an engorged female to remain non-gonoactive. The necessity for a second blood meal is present in any female, but small mosquitoes are more likely to bite again within a 2-day interval, in order to attain egg maturation.OBJETIVO: Estimar la probabilidad para que una hembra de Aedes aegypti, previamente alimentada con sangre humana, permanezca no gonoactiva, sin madurar huevos, dependiendo del tamaño corporal y tipo de colecta. MATERIAL Y MÉTODOS: Se hicieron 10 muestreos de Ae aegypti

  9. Experience- and age-mediated oviposition behaviour in the yellow fever mosquito Stegomyia aegypti (=Aedes aegypti).

    Science.gov (United States)

    Ruktanonchai, N W; Lounibos, L P; Smith, D L; Allan, S A

    2015-09-01

    In repeated behaviours such as those of feeding and reproduction, past experiences can inform future behaviour. By altering their behaviour in response to environmental stimuli, insects in highly variable landscapes can tailor their behaviour to their particular environment. In particular, female mosquitoes may benefit from plasticity in their choice of egg-laying site as these sites are often temporally variable and clustered. The opportunity to adapt egg-laying behaviour to past experience also exists for mosquito populations as females typically lay eggs multiple times throughout their lives. Whether experience and age affect egg-laying (or oviposition) behaviour in the mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) was assessed using a wind tunnel. Initially, gravid mosquitoes were provided with a cup containing either repellent or well water. After ovipositing in these cups, the mosquitoes were blood-fed and introduced into a wind tunnel. In this wind tunnel, an oviposition cup containing repellent was placed in the immediate vicinity of the gravid mosquitoes. A cup containing well water was placed at the opposite end of the tunnel so that if the females flew across the chamber, they encountered the well water cup, in which they readily laid eggs. Mosquitoes previously exposed to repellent cups became significantly more likely to later lay eggs in repellent cups, suggesting that previous experience with suboptimal oviposition sites informs mosquitoes of the characteristics of nearby oviposition sites. These results provide further evidence that mosquitoes modify behaviour in response to environmental information and are demonstrated in a vector species in which behavioural plasticity may be ecologically and epidemiologically meaningful. PMID:25982411

  10. PENGENDALIAN JENTIK Aedes Aegypti MENGGUNAKAN Mesocyclops Aspericomis MELALUI PARTISIPASI MASYARAKAT

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    Umi Widyastuti

    2012-07-01

    Full Text Available Mesocyclops aspericornis was investigated for its effectiveness in controlling Aedes aegypti larvae in a variety of containers e.g metal drum, cistern, clay jars, and other container made of plastic. A study was carried out in Kenteng hamlet, Tegalrejo village, Salatiga Municipality. It was conducted by health-workers (staff of Vector and Reservoir Control Research Unit and Health Center of Tegalrejo and the community, especially the woman's organization namely "family empowering and welfareness ". which participate in releasing M. aspericornis for controlling Ae. aegypti larvae. The community has responsibility to release M. aspericornis in Kenteng RT01 and 02 as the treated area I. Meanwhile, Health-workers have responsibility to release it in Kenteng RT 04, 05, and 07 as the treated area II and Kenteng RT 03 and 06 as the untreated control area (no M. aspericornis released. The aim of the study were: a, to determine the effectiveness of M. aspericornis in decreasing larval populations of Ae. aegypti in the containers, and b. to determine the Knowledge, Attitude, and Practice (KAP of the community, referring to disease, vector and control of Dengue Haemorhagic Fever (DHF. M. aspericornis was effective to decrease larval populations of Ae. aegypti in Kenteng area. The increasing number of Ae. aegypti larvae free containers of 24.29-84,02% and 35.75-92.01% were shown in respectively treated area I and II. The KAP of the community referring to disease, vector and control of DHF increased after the health education conducted. It's concluded that the community of Kenteng hamlet is active in participation to control Ae. aegypti. As a recommend, control of Ae. aegypti larvae using M. aspericornis through community partisipation should be considered due to a good prospect and effectiveness of this agent to control of Ae. aegypti larvae in the laboratory as well as in the field   Key words : Vector control, M. aspericornis, Ae. aegypti, Dengue

  11. EFFICACY OF THAI NEEM OIL AGAINST AEDES AEGYPTI (L.) LARVAE.

    Science.gov (United States)

    Silapanuntakul, Suthep; Keanjoom, Romnalin; Pandii, Wongdyan; Boonchuen, Supawadee; Sombatsiri, Kwanchai

    2016-05-01

    Trees with larvicidal activity may be found in Thailand. We conducted this study to evaluate the efficacy and length of efficacy of Thai neem (Azadirachta siamensis) oil emulsion and an alginate bead of Thai neem oil formulation against early fourth stage Aedes aegypti larvae using a dipping test. The Thai neem oil emulsion had significantly greater larvicidal activity than the alginate bead formulation at 12 to 60 hours post-exposure (p neem oil formulation resulted in 100% mortality among the early fourth stage Aedes aegypti larvae at 48 hours, while the alginate bead formulation resulted in 98% larval mortality at 84 hours and 100% mortality at 96 hours. The mean larval mortality using the Thai neem oil emulsion dropped to < 25% by 12 days and with the alginate beads dropped to < 25% by 15 days of exposure.

  12. Sodium Channel Mutations and Pyrethroid Resistance in Aedes aegypti

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    Yuzhe Du

    2016-10-01

    Full Text Available Pyrethroid insecticides are widely used to control insect pests and human disease vectors. Voltage-gated sodium channels are the primary targets of pyrethroid insecticides. Mutations in the sodium channel have been shown to be responsible for pyrethroid resistance, known as knockdown resistance (kdr, in various insects including mosquitoes. In Aedes aegypti mosquitoes, the principal urban vectors of dengue, zika, and yellow fever viruses, multiple single nucleotide polymorphisms in the sodium channel gene have been found in pyrethroid-resistant populations and some of them have been functionally confirmed to be responsible for kdr in an in vitro expression system, Xenopus oocytes. This mini-review aims to provide an update on the identification and functional characterization of pyrethroid resistance-associated sodium channel mutations from Aedes aegypti. The collection of kdr mutations not only helped us develop molecular markers for resistance monitoring, but also provided valuable information for computational molecular modeling of pyrethroid receptor sites on the sodium channel.

  13. EFFICACY OF THAI NEEM OIL AGAINST AEDES AEGYPTI (L.) LARVAE.

    Science.gov (United States)

    Silapanuntakul, Suthep; Keanjoom, Romnalin; Pandii, Wongdyan; Boonchuen, Supawadee; Sombatsiri, Kwanchai

    2016-05-01

    Trees with larvicidal activity may be found in Thailand. We conducted this study to evaluate the efficacy and length of efficacy of Thai neem (Azadirachta siamensis) oil emulsion and an alginate bead of Thai neem oil formulation against early fourth stage Aedes aegypti larvae using a dipping test. The Thai neem oil emulsion had significantly greater larvicidal activity than the alginate bead formulation at 12 to 60 hours post-exposure (p Aedes aegypti larvae at 48 hours, while the alginate bead formulation resulted in 98% larval mortality at 84 hours and 100% mortality at 96 hours. The mean larval mortality using the Thai neem oil emulsion dropped to < 25% by 12 days and with the alginate beads dropped to < 25% by 15 days of exposure. PMID:27405123

  14. A leucokinin mimic elicits aversive behavior in mosquito Aedes aegypti (L.) and inhibits the sugar taste neuron

    Science.gov (United States)

    Insect kinins (leucokinins) are multifunctional peptides acting as neurohormones and neurotransmitters. In females of the mosquito vector Aedes aegypti (L.), aedeskinins are known to stimulate fluid secretion from the renal organs (Malpighian tubules) and hindgut contractions by activating a G prot...

  15. Rapid and non-destructive detection and identification two strains of Wolbachia in Aedes aegypti by near-infrared spectroscopy

    Science.gov (United States)

    We investigated the potential of using near-infrared spectroscopy (NIRS) to detect the presence of Wolbachia pipientis (wMel) in male and female laboratory-reared Aedes aegypti mosquitoes. The release of Wolbachia transinfected mosquitoes is likely to form a key component of disease control strategi...

  16. Intriguing olfactory proteins from the yellow fever mosquito, Aedes aegypti

    Science.gov (United States)

    Ishida, Yuko; Chen, Angela M.; Tsuruda, Jennifer M.; Cornel, Anthon J.; Debboun, Mustapha; Leal, Walter S.

    2004-09-01

    Four antennae-specific proteins (AaegOBP1, AaegOBP2, AaegOBP3, and AaegASP1) were isolated from the yellow fever mosquito, Aedes aegypti and their full-length cDNAs were cloned. RT-PCR indicated that they are expressed in female and, to a lesser extent, in male antennae, but not in control tissues (legs). AaegOBP1 and AaegOBP3 showed significant similarity to previously identified mosquito odorant-binding proteins (OBPs) in cysteine spacing pattern and sequence. Two of the isolated proteins have a total of eight cysteine residues. The similarity of the spacing pattern of the cysteine residues and amino acid sequence to those of previously identified olfactory proteins suggests that one of the cysteine-rich proteins (AaegOBP2) is an OBP. The other (AaegASP1) did not belong to any group of known OBPs. Structural analyses indicate that six of the cysteine residues in AaegOBP2 are linked in a similar pattern to the previously known cysteine pairing in OBPs, i.e., Cys-24 Cys-55, Cys-51 Cys-104, Cys-95 Cys-113. The additional disulfide bridge, Cys-38 Cys-125, knits the extended C-terminal segment of the protein to a predicted α2-helix. As indicated by circular dichroism (CD) spectra, the extra rigidity seems to prevent the predicted formation of a C-terminal α-helix at low pH.

  17. Similarity solutions for systems arising from an Aedes aegypti model

    Science.gov (United States)

    Freire, Igor Leite; Torrisi, Mariano

    2014-04-01

    In a recent paper a new model for the Aedes aegypti mosquito dispersal dynamics was proposed and its Lie point symmetries were investigated. According to the carried group classification, the maximal symmetry Lie algebra of the nonlinear cases is reached whenever the advection term vanishes. In this work we analyze the family of systems obtained when the wind effects on the proposed model are neglected. Wide new classes of solutions to the systems under consideration are obtained.

  18. Intraspecific Competition and Population Dynamics of Aedes aegypti

    Science.gov (United States)

    Paixão, C. A.; Charret, I. C.; Lima, R. R.

    2012-04-01

    We report computational simulations for the evolution of the population of the dengue vector, Aedes aegypti mosquitoes. The results suggest that controlling the mosquito population, on the basis of intraspecific competition at the larval stage, can be an efficient mechanism for controlling the spread of the epidemic. The results also show the presence of a kind of genetic evolution in vector population, which results mainly in increasing the average lifespan of individuals in adulthood.

  19. Atmospheric control of Aedes aegypti populations in Buenos Aires (Argentina) and its variability

    Science.gov (United States)

    de Garín, A.; Bejarán, R. A.; Carbajo, A. E.; de Casas, S. C.; Schweigmann, N. J.

    The mosquito Aedes aegypti is the main urban vector responsible for the transmission of dengue fever and dengue hemorrhagic fever. The city of Buenos Aires, Argentina, is located at the southern end of the world distribution of the species. The population abundance of Ae. aegypti is mainly regulated by environmental factors. We calculated the potential number of times that a female could lay eggs during its mean life expectancy, based on potential egg production and daily meteorological records. The model considers those variables implying physical hazard to the survival of Ae. aegypti, mosquito flying activity and oviposition. The results, obtained after calibration and validation of the model with field observations, show significant correlation (Pclimatic change) can be observed. The climatic variability in the last decade resembles conditions at the end of 19th century.

  20. Atmospheric control of Aedes aegypti populations in Buenos Aires (Argentina) and its variability

    Science.gov (United States)

    de Garín, A.; Bejarán, R. A.; Carbajo, A. E.; de Casas, S. C.; Schweigmann, N. J.

    The mosquito Aedes aegypti is the main urban vector responsible for the transmission of dengue fever and dengue hemorrhagic fever. The city of Buenos Aires, Argentina, is located at the southern end of the world distribution of the species. The population abundance of Ae. aegypti is mainly regulated by environmental factors. We calculated the potential number of times that a female could lay eggs during its mean life expectancy, based on potential egg production and daily meteorological records. The model considers those variables implying physical hazard to the survival of Ae. aegypti, mosquito flying activity and oviposition. The results, obtained after calibration and validation of the model with field observations, show significant correlation (Paegypti reproduction (linked to the urban climatic change) can be observed. The climatic variability in the last decade resembles conditions at the end of 19th century.

  1. Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development.

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    Jill N Ulrich

    2016-07-01

    Full Text Available The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30-40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20-30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20-30°C for 4-7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal.

  2. Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development.

    Science.gov (United States)

    Ulrich, Jill N; Beier, John C; Devine, Gregor J; Hugo, Leon E

    2016-07-01

    The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30-40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20-30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20-30°C for 4-7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal.

  3. Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development

    Science.gov (United States)

    Beier, John C.; Devine, Gregor J.; Hugo, Leon E.

    2016-01-01

    The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30–40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20–30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20–30°C for 4–7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal. PMID:27459519

  4. Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development.

    Science.gov (United States)

    Ulrich, Jill N; Beier, John C; Devine, Gregor J; Hugo, Leon E

    2016-07-01

    The wMel strain of Wolbachia bacteria is known to prevent dengue and Zika virus transmission in the mosquito vector Aedes aegypti. Accordingly, the release of wMel-infected A. aegypti in endemic regions has been recommended by the World Health Organization as a potential strategy for controlling dengue and Zika outbreaks. However, the utility of this approach could be limited if high temperatures in the aquatic habitats where A. aegypti develop are detrimental to Wolbachia. We exposed wMel-infected A. aegypti eggs and larvae to fluctuating daily temperatures of 30-40°C for three, five, or seven days during their development. We found that Wolbachia levels in females emerging from heat treatments were significantly lower than in the controls that had developed at 20-30°C. Notably, seven days of high temperatures starting at the egg stage reduced Wolbachia levels in emerging females to less than 0.1% of the wMel control levels. However, after adult females returned to 20-30°C for 4-7 days, they experienced differing degrees of Wolbachia recovery. Our findings suggest that the spread of Wolbachia in wild A. aegypti populations and any consequent protection from dengue and Zika viruses might be limited in ecosystems that experience periods of extreme heat, but Wolbachia levels recover partially after temperatures return to normal. PMID:27459519

  5. Mosquitocidal and Oviposition Repellent Activities of the Extracts of Seaweed Bryopsis pennata on Aedes aegypti and Aedes albopictus.

    Science.gov (United States)

    Yu, Ke-Xin; Wong, Ching-Lee; Ahmad, Rohani; Jantan, Ibrahim

    2015-01-01

    The ever-increasing threat from infectious diseases and the development of insecticide resistance in mosquito populations drive the global search for new natural insecticides. The aims of this study were to evaluate the mosquitocidal activity of the extracts of seaweed Bryopsis pennata against dengue vectors Aedes aegypti and Aedes albopictus, and determine the seaweed's toxic effect on brine shrimp nauplii (as a non-target organism). In addition, the chemical compositions of the active larvicidal extract and fraction were analyzed by using liquid chromatography-mass spectrometry (LC-MS). Chloroform extract exhibited strong ovicidal activity (with LC50 values of 229.3 and 250.5 µg/mL) and larvicidal activity against Ae. aegypti and Ae. albopictus. The larvicidal potential of chloroform extract was further ascertained when its A7 fraction exhibited strong toxic effect against Ae. aegypti (LC50 = 4.7 µg/mL) and Ae. albopictus (LC50 = 5.3 µg/mL). LC-MS analysis of the chloroform extract gave a tentative identification of 13 compounds; Bis-(3-oxoundecyl) tetrasulfide was identified as the major compound in A7 fraction. Methanol extract showed strong repellent effect against female oviposition, along with weak adulticidal activity against mosquito and weak toxicity against brine shrimp nauplii. The mosquitocidal results of B. pennata suggest further investigation for the development of effective insecticide.

  6. Mosquitocidal and Oviposition Repellent Activities of the Extracts of Seaweed Bryopsis pennata on Aedes aegypti and Aedes albopictus

    Directory of Open Access Journals (Sweden)

    Ke-Xin Yu

    2015-08-01

    Full Text Available The ever-increasing threat from infectious diseases and the development of insecticide resistance in mosquito populations drive the global search for new natural insecticides. The aims of this study were to evaluate the mosquitocidal activity of the extracts of seaweed Bryopsis pennata against dengue vectors Aedes aegypti and Aedes albopictus, and determine the seaweed’s toxic effect on brine shrimp nauplii (as a non-target organism. In addition, the chemical compositions of the active larvicidal extract and fraction were analyzed by using liquid chromatography-mass spectrometry (LC-MS. Chloroform extract exhibited strong ovicidal activity (with LC50 values of 229.3 and 250.5 µg/mL and larvicidal activity against Ae. aegypti and Ae. albopictus. The larvicidal potential of chloroform extract was further ascertained when its A7 fraction exhibited strong toxic effect against Ae. aegypti (LC50 = 4.7 µg/mL and Ae. albopictus (LC50 = 5.3 µg/mL. LC-MS analysis of the chloroform extract gave a tentative identification of 13 compounds; Bis-(3-oxoundecyl tetrasulfide was identified as the major compound in A7 fraction. Methanol extract showed strong repellent effect against female oviposition, along with weak adulticidal activity against mosquito and weak toxicity against brine shrimp nauplii. The mosquitocidal results of B. pennata suggest further investigation for the development of effective insecticide.

  7. EFEKTIFITAS EKSTRAK BUAH PARE (Momordica Charantia DALAM MEMATIKAN JENTIK AEDES AEGYPTI

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    Ilham Syam

    2016-03-01

    Full Text Available Demam dengue dan demam berdarah dengue adalah penyakit virus yang tersebar luas di seluruh dunia terutama di daerah tropis Sumber penularan utama adalah manusia dan primata, sedang penularnya adalah nyamuk Aedes aegypti. Penelitian ini bertujuan untuk mengetahui kemampuan ekstrak buah pare (Momordica charantia dalam mematikan jentik Aedes aegypti dengan konsentrasi 5%, 10% dan 15% dalam waktu 8 jam dengan pengamatan setiap 30 menit disetiap konsentrasinya. Metode Penelitian ini adalah Quasi Experiment dengan rancangan penelitian rangkaian waktu (Time Series Design. Penelitian menunjukkan kematian jentik Aedes aegypti pada konsentrasi 5% dapat mematikan jentik sebesar 48% dari jumlah populasi jentik Aedes aegypti. Konsentrasi 10% dapat mematikan jentik dengan persentase kematian sebesar 66% dari jumlah populasi jentik Aedes aegypti. Sedangkan, kematian jentik dengan konsentrasi 15% mencapai persentase kematian sebesar 89% dari jumlah populasi jentik Aedes aegypti. Simpulan yang diperoleh dalam penelitian ini adalah adanya pengaruh ekstrak buah pare dalam mematikan jentik Aedes aegypti pada konsentrasi 5%, 10% dan 15%.Kata Kunci: Aedes aegypti, Ekstrak Buah Pare (Momordica Charantia

  8. Oviposition and Embryotoxicity of Indigofera suffruticosa on Early Development of Aedes aegypti (Diptera: Culicidae

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    Jeymesson Raphael Cardoso Vieira

    2012-01-01

    Full Text Available Aqueous extract of Indigofera suffruticosa leaves obtained by infusion was used to evaluate the oviposition, its effect on development of eggs and larvae, and morphological changes in larvae of Aedes aegypti. The bioassays were carried out with aqueous extract in different concentrations on eggs, larvae, and female mosquitoes, and the morphological changes were observed in midgut of larvae. The extract showed repellent activity on A. aegypti mosquitoes, reducing significantly the egg laying by females with control substrate (343 (185–406 compared with the treated substrate (88 (13–210. No eclosion of A. aegypti eggs at different concentrations studied was observed. The controleclodedin 35%. At concentration of 250 μg/mL, 93.3% of larvae remained in the second instar of development and at concentrations of 500, 750, and 1000 μg/mL the inhibitory effect was lower with percentages of 20%, 53.3%, and 46.6%, respectively. Morphological changes like disruption on the peritrophic envelope (PE, discontinued underlying epithelium, increased gut lumen, and segments with hypertrophic aspects were observed in anterior region of medium midgut of larvae of A. aegypti. The results showed repellent activity, specific embryotoxicity, and general growth retardation in A. aegypti by medium containing aqueous extract of I. suffruticosa leaves.

  9. A RE-SURVEY OF AEDES AEGYPTI AND AEDES ALBOPICTUS IN SABAH, MALAYSIA

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    Feffrey Hii Lu King

    2012-09-01

    Full Text Available Di Sabah, Malaysia telah diadakan survey nyamuk Aedes aegypti dan Aedes albopictus dari bulan Agustus s/d September 1974 dan Maret-April 1975. Survey dilakukan pada 5 daerah di Kudat. Pantai Barat, Pedalaman Sandahan danTawan dengan tujuan untuk melihat distribusi dan density dari kedua jenis nyamuk tsb. Hasil survey menunjukkan bahwa nyamuk A. aegypti telah menyebar pada hampir seluruh daerah pantai Sabah, dan ditemukan hampir pada sebagian besar kotal dan daerah pedesaan di banyak desa. Di bandingkan dengan hasil survey yang pernah dilakukan pada tahun 1970 oleh Ramalingam ternyata terdapat pertambahan 24 persen daerah A. aegypti, dari 58.7 persen daerah A. albopictus selama 4 tahun. A. aegypti sangat biasa terdapat di desa2 pantai sebelah timur, dan ditempat-tempat lainnya menunjukkan Breteau index yang tinggi. Diduga adanya perahu2 dan tempat2 penampungan air merupakan faktor yang penting dalam penyebaran nyamuk. Walaupun tidak terdapat epidemi dengue dan demam berdarah di Sabah, tetapi ada indikasi risiko trahsmissi yang besar di daerah2 dimana Breteau index lebih dari 50. Dari hasil survey ini strategi pemberantasan A. aegypti dapat dikembangkan untuk mencegah terjadinya epidemi dengue dan demam berdarah.

  10. Evaluation of Bifenthrin and Acorus calamus Linn. Extract against Aedes aegypti L. and Aedes albopictus (Skuse

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    S Sulaiman

    2008-12-01

    Full Text Available "nBackground: Bifenthrin and Acorus calamus Linn extract were evaluated against dengue vectors in the laboratory."nMethods: Both Bifenthrin and Acorus calamus Linn crude hexane extract were bioassayed against the adults and larval stages of dengue vectors Aedes aegypti L. and Aedes albopictus(Skuse in the laboratory."nResults: The A. calamus crude hexane extract exhibited a larvicidal activity against 4th-instar Ae. aegypti larvae with LC50 and LC90 values of 0.4418 and 11.3935 ppm respectively. The plant crude extract exhibited against Ae. albopictus larvae with a higher LC50 and LC90 values of 21.2555 ppm and 36.1061 ppm, respectively. There was a significant difference on the effect of A. calamus extract on both Aedes spp. Larvae (P< 0.05. However, bifenthrin showed a significant difference on larvicidal effect to that of A. calamus hexane extract on both Aedes spp (P< 0.05. In testing the adulticidal activity, this plant extract exhibited the LC50 and LC90 values of 17.4075 and 252.9458 ppm against Ae .aegypti and a higher LC50 and LC90 values of 43.9952 and 446.1365 ppm respectively on Ae. albopictus. There was no significant difference on the effect of A. calamus extract on both Aedes spp adults (P> 0.05."nConclusion: Bifenthrin however showed a significant difference on both Aedes spp adults (P< 0.05. With the wide availability of A. calamus in Malaysia, it could be utilized for controlling dengue vectors. "n 

  11. Evaluation of a sticky trap (AedesTraP, made from disposable plastic bottles, as a monitoring tool for Aedes aegypti populations

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    de Santos Eloína Maria

    2012-09-01

    Full Text Available Abstract Background Dengue virus, which is transmitted by Aedes aegypti mosquitoes is the most important emerging viral disease, infecting more than 50 million people annually. Currently used sticky traps are useful tools for monitoring and control of A. aegypti, despite differences in efficiency, labor requirements and cost. In the present work, a field assay was carried out to evaluate the performance of a sticky trap (AedesTrap, produced using disposable material, in capturing gravid Aedes spp. females. Additionally, conditions necessary for the improved performance of the device, such as number of traps per site and location (indoors or outdoors were evaluated. Methods During a one year period, traps were placed in a dengue endemic area in 28 day cycles. The trap, named AedesTrap, consisted of a disposable plastic soda bottle coated inside with colophony resin, which served as a sticky substrate. Disposable bottles were donated by restaurants, and traps were made by laboratory staff, reducing the cost of the sticky trap (less than U$3. Mosquito capture in indoor and outdoor areas was compared by placing the traps in laundry room, kitchen or bedroom (indoors and front or back yard (outdoors. The relationship between the number of AedesTraps and quantity of captured mosquitoes was investigated by utilizing one or three traps/site. Results During a 28 day cycle, a single AedesTrap was capable of capturing up to 15 A. aegypti in a house, with a mean capture of 0.5 to 2.63 females per premise. The AedesTrap collected three times more outdoors versus indoors. Similarly, the capability of detecting Aedes spp. infestation, and of capturing females, was three times higher when using three AedesTraps per house, compared with one trap per house. Conclusions AedesTrap was shown to be capable of capturing A. aegypti and other culicidae, providing information on the adult mosquito population, and allowing the identification of areas critically

  12. Influence of breeding site availability on the oviposition behaviour of Aedes aegypti

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    Filipe Vieira Santos de Abreu

    2015-08-01

    Full Text Available Despite the importance of the mosquito Aedes aegypti in the transmission of arboviruses, such as yellow fever, Chikungunya fever and dengue fever, some aspects of their behaviour remain unknown. In the present study, the oviposition behaviour of Ae. aegypti females that were exposed to different densities of breeding sites (2, 4, 8 and 16 was evaluated in laboratory and semi-field conditions. The number of breeding sites that were used was proportional to the number available, but tended towards stabilisation. Females used four-six breeding sites on average, with a maximum of 11. A high percentage of eggs was observed in the water, along with the presence of a breeding site termed “favourite”, which received at least 40% of the eggs. The results are discussed in ecological, evolutionary and epidemiological approaches.

  13. Influence of breeding site availability on the oviposition behaviour of Aedes aegypti

    Science.gov (United States)

    de Abreu, Filipe Vieira Santos; Morais, Maira Moreira; Ribeiro, Sérvio Pontes; Eiras, Álvaro Eduardo

    2015-01-01

    Despite the importance of the mosquito Aedes aegypti in the transmission of arboviruses, such as yellow fever, Chikungunya fever and dengue fever, some aspects of their behaviour remain unknown. In the present study, the oviposition behaviour of Ae. aegypti females that were exposed to different densities of breeding sites (2, 4, 8 and 16) was evaluated in laboratory and semi-field conditions. The number of breeding sites that were used was proportional to the number available, but tended towards stabilisation. Females used four-six breeding sites on average, with a maximum of 11. A high percentage of eggs was observed in the water, along with the presence of a breeding site termed “favourite”, which received at least 40% of the eggs. The results are discussed in ecological, evolutionary and epidemiological approaches. PMID:26154742

  14. Pyrethroid resistance in Aedes aegypti larvae (Diptera: Culicidae) from Singapore.

    Science.gov (United States)

    Koou, Sin-Ying; Chong, Chee-Seng; Vythilingam, Indra; Ng, Lee-Ching; Lee, Chow-Yang

    2014-01-01

    We report the first comprehensive insecticide susceptibility status ofAedes aegypti (L.) larvae from Singapore. The study indicated that Ae. aegypti is susceptible to temephos, although resistance (RR50 = 1.29-4.43-fold) couldbe developing. Of high concern is the detection of moderate to high resistance to permethrin (RR50 = 29-47-fold) and etofenprox (RR50 = 14-34-fold). Biolarvicide Bacillus thuringiensis israelensis (Bti) remains effective. The insecticide susceptibility profile of Ae. aegypti larvae was found to be homogenous among the different sites studied across the island city. The addition of synergists piperonyl butoxide, S,S,S,-tributyl phosphorotrithioate, and triphenyl phosphate generally failed to enhance the toxicity of the insecticides investigated, suggesting an insignificant role of metabolic-based resistance, and a possible involvement of target site resistance. Further biochemical investigation of specific metabolic enzyme activities suggested that detoxifying enzymes, mono-oxygenases, esterases, glutathione S-transferases, and altered acetylcholinesterases, generally did not contribute to the resistance observed. This study clearly demonstrated that pyrethroid resistance is widespread among Ae. aegypti population and lowered susceptibility to organophosphates is developing. PMID:24605467

  15. Genome sequence of Aedes aegypti, a major arbovirus vector.

    Science.gov (United States)

    Nene, Vishvanath; Wortman, Jennifer R; Lawson, Daniel; Haas, Brian; Kodira, Chinnappa; Tu, Zhijian Jake; Loftus, Brendan; Xi, Zhiyong; Megy, Karyn; Grabherr, Manfred; Ren, Quinghu; Zdobnov, Evgeny M; Lobo, Neil F; Campbell, Kathryn S; Brown, Susan E; Bonaldo, Maria F; Zhu, Jingsong; Sinkins, Steven P; Hogenkamp, David G; Amedeo, Paolo; Arensburger, Peter; Atkinson, Peter W; Bidwell, Shelby; Biedler, Jim; Birney, Ewan; Bruggner, Robert V; Costas, Javier; Coy, Monique R; Crabtree, Jonathan; Crawford, Matt; Debruyn, Becky; Decaprio, David; Eiglmeier, Karin; Eisenstadt, Eric; El-Dorry, Hamza; Gelbart, William M; Gomes, Suely L; Hammond, Martin; Hannick, Linda I; Hogan, James R; Holmes, Michael H; Jaffe, David; Johnston, J Spencer; Kennedy, Ryan C; Koo, Hean; Kravitz, Saul; Kriventseva, Evgenia V; Kulp, David; Labutti, Kurt; Lee, Eduardo; Li, Song; Lovin, Diane D; Mao, Chunhong; Mauceli, Evan; Menck, Carlos F M; Miller, Jason R; Montgomery, Philip; Mori, Akio; Nascimento, Ana L; Naveira, Horacio F; Nusbaum, Chad; O'leary, Sinéad; Orvis, Joshua; Pertea, Mihaela; Quesneville, Hadi; Reidenbach, Kyanne R; Rogers, Yu-Hui; Roth, Charles W; Schneider, Jennifer R; Schatz, Michael; Shumway, Martin; Stanke, Mario; Stinson, Eric O; Tubio, Jose M C; Vanzee, Janice P; Verjovski-Almeida, Sergio; Werner, Doreen; White, Owen; Wyder, Stefan; Zeng, Qiandong; Zhao, Qi; Zhao, Yongmei; Hill, Catherine A; Raikhel, Alexander S; Soares, Marcelo B; Knudson, Dennis L; Lee, Norman H; Galagan, James; Salzberg, Steven L; Paulsen, Ian T; Dimopoulos, George; Collins, Frank H; Birren, Bruce; Fraser-Liggett, Claire M; Severson, David W

    2007-06-22

    We present a draft sequence of the genome of Aedes aegypti, the primary vector for yellow fever and dengue fever, which at approximately 1376 million base pairs is about 5 times the size of the genome of the malaria vector Anopheles gambiae. Nearly 50% of the Ae. aegypti genome consists of transposable elements. These contribute to a factor of approximately 4 to 6 increase in average gene length and in sizes of intergenic regions relative to An. gambiae and Drosophila melanogaster. Nonetheless, chromosomal synteny is generally maintained among all three insects, although conservation of orthologous gene order is higher (by a factor of approximately 2) between the mosquito species than between either of them and the fruit fly. An increase in genes encoding odorant binding, cytochrome P450, and cuticle domains relative to An. gambiae suggests that members of these protein families underpin some of the biological differences between the two mosquito species. PMID:17510324

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

    Science.gov (United States)

    Canyon, D V; Muller, R

    2013-12-01

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

  17. Risk factors for the presence of Aedes aegypti and Aedes albopictus in domestic water-holding containers in areas impacted by the Nam Theun 2 hydroelectric project, Laos

    NARCIS (Netherlands)

    Hiscox, A.F.; Kaye, A.; Vongphayloth, K.; Banks, I.; Piffer, M.; Khammanithong, P.; Sananikhom, P.; Kaul, S.; Hill, N.; Lindsay, S.W.; Brey, P.T.

    2013-01-01

    We assessed risk factors for vectors of dengue and chikungunya viruses near a new hydroelectric project, Nam Theun 2, in Laos. Immature stages of Aedes aegypti were found only in sites within 40 km of the urban provincial capital, but Aedes albopictus was found throughout. Aedes aegypti pupae were m

  18. Resistance of Aedes aegypti to temephos and adaptive disadvantages

    OpenAIRE

    Morgana Michele Cavalcanti de Souza Leal Diniz; Alleksandra Dias da Silva Henriques; Renata da Silva Leandro; Dalvanice Leal Aguiar; Eduardo Barbosa Beserra

    2014-01-01

    OBJECTIVE To evaluate the resistance of Aedes aegypti to temephos Fersol 1G (temephos 1% w/w) associated with the adaptive disadvantage of insect populations in the absence of selection pressure. METHODS A diagnostic dose of 0.28 mg a.i./L and doses between 0.28 mg a.i./L and 1.40 mg a.i./L were used. Vector populations collected between 2007 and 2008 in the city of Campina Grande, state of Paraíba, were evaluated. To evaluate competition in the absence of selection pressure, insect popul...

  19. The effect of Piper aduncum Linn. (Family: Piperaceae) essential oil as aerosol spray against Aedes aegypti (L.) and Aedes albopictus Skuse.

    Science.gov (United States)

    Misni, Norashiqin; Othman, Hidayatulfathi; Sulaiman, Sallehudin

    2011-08-01

    The bioefficacy of Piper aduncum L. essential oil formulated in aerosol cans was evaluated against Aedes aegypti and Aedes albopictus in a simulated room. The aerosol spray test was based on the Malaysian test standard for aerosol (MS 1221:1991UDC 632.982.2 modified from WHO 2009 methodology) and examined the knockdown effect within 20 minutes of exposure. Mortality rate after 24 hour of holding period was also determined. A commercial aerosol spray (0.09% prallethrin 0.05% d-phenothrin) was also tested as a comparison. Our results showed that the knockdown effect of the commercial aerosol spray and P. aduncum essential oil spray (8% and 10% concentrations) was significantly higher in Ae. albopictus adult females, when compared with that of Ae. aegypti adult females (Pspp. (Pspp. PMID:22041743

  20. A technique for preparing polytene chromosomes from Aedes aegypti (Diptera, Culicinae

    Directory of Open Access Journals (Sweden)

    Jairo Campos

    2003-04-01

    Full Text Available Polytene chromosome preparations were obtained from larval, pupal and adult female Malpighian tubules of Aedes aegypti. The Malpighian tubules of the pupae (0-4 h old from larvae reared at 20ºC provided the best cytogenetic analysis. The interaction of nucleic acids and proteins that influence the spreading of the chromosomes could be reduced with the preparation technique of the sheets submitted to a stronger treatment starting with the hypotony of tissue and successive bathings with acetic acid. A simple technique should facilitate molecular cytogenetics used in the location of resistance and vector competence genes.

  1. Laboratory evaluation of the response of Aedes aegypti and Aedes albopictus uninfected and infected with dengue virus to deet

    Science.gov (United States)

    Laboratory studies were conducted to compare the response of Aedes aegypti (L.) and Aedes albopictus (Skuse) adults, uninfected and infected with four serotypes of dengue virus, to a repellent containing 5% deet. The results showed that mosquitoes infected with the four serotypes of dengue respond i...

  2. Prevalence of Aedes aegypti Linnaeus and Aedes albopictus Skuse in Koderma, Jharkhand.

    Science.gov (United States)

    Singh, R K; Dhiman, R C; Dua, V K

    2011-09-01

    Entomological survey was carried out in different localities of Koderma district of Jharkhand with a view to study the prevalence, distribution and stratification of areas for Aedes mosquito species. A total of 233 houses were covered during house to house larval and adult survey. Aedes breeding could be detected in 157 houses. In all, a total of 942 domestic water containers were searched, out of which 461 were found positive. The overall house index(HI) container index(CI) breteau index(B1) and pupal index(PI) were 67.38%, 48.94%, 197.85% and 79.4%, respectively. The survey revealed that Aedes aegypti Linnaeus and Aedes albopictus Skuse are well established in Koderma with most of the areas showing high adult and larval indices. The preventive strategy needs to be directed towards minimizing the breeding potential of Aedes and water management practice by individuals along with implementation of urban bye-laws as well as IEC activities to contain Aedes breeding in future. PMID:23781636

  3. Assessing the feasibility of controlling Aedes aegypti with transgenic methods: a model-based evaluation.

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    Mathieu Legros

    Full Text Available Suppression of dengue and malaria through releases of genetically engineered mosquitoes might soon become feasible. Aedes aegypti mosquitoes carrying a conditionally lethal transgene have recently been used to suppress local vector populations in small-scale field releases. Prior to releases of transgenic insects on a wider scale, however, most regulatory authorities will require additional evidence that suppression will be effective in natural heterogeneous habitats. We use a spatially explicit stochastic model of an Ae. aegypti population in Iquitos, Peru, along with an uncertainty analysis of its predictions, to quantitatively assess the outcome of varied operational approaches for releases of transgenic strains with conditional death of females. We show that population elimination might be an unrealistic objective in heterogeneous populations. We demonstrate that substantial suppression can nonetheless be achieved if releases are deployed in a uniform spatial pattern using strains combining multiple lethal elements, illustrating the importance of detailed spatial models for guiding genetic mosquito control strategies.

  4. Contrasting patterns of insecticide resistance and knockdown resistance (kdr) in the dengue vectors Aedes aegypti and Aedes albopictus from Malaysia

    OpenAIRE

    Ishak, Intan H; Jaal, Zairi; Ranson, Hilary; Charles S Wondji

    2015-01-01

    Background Knowledge on the extent, distribution and mechanisms of insecticide resistance is essential for successful insecticide-based dengue control interventions. Here, we report an extensive resistance profiling of the dengue vectors Aedes aegypti and Aedes albopictus across Malaysia and establish the contribution of knockdown resistance mechanism revealing significant contrast between both species. Methods Aedes mosquitoes were collected from four states in Malaysia in 2010 using ovitrap...

  5. Larvicide and oviposition deterrent effects of fruit and leaf extracts from Melia azedarach L. on Aedes aegypti (L.) (Diptera: Culicidae).

    Science.gov (United States)

    Coria, C; Almiron, W; Valladares, G; Carpinella, C; Ludueña, F; Defago, M; Palacios, S

    2008-05-01

    Aedes aegypti (L.) (Diptera: Culicidae), the main urban vector of dengue, has developed resistance to various insecticides, making its control increasingly difficult. We explored the effects of Argentine Melia azedarach L. (Meliaceae) fruit and senescent leaf extracts on Ae. aegypti larval development and survival, by rearing cohorts of first instar mosquitoes in water with different extract concentrations. We also analysed oviposition deterrent activity in choice tests with extract-treated ovitraps. The leaf extract showed a strong larvicide activity, with all larvae dying before pupation, and significantly delayed development time. It strongly inhibited oviposition by Ae. aegypti females. The fruit extract showed much weaker effects. This first report of highly effective larvicidal, growth regulating and oviposition deterrent activity of a senescent leaf extract of M. azedarach against Ae. aegypti, suggests that such extract could represent a promising tool in the management of this mosquito pest.

  6. Vector Competence of Aedes aegypti and Aedes polynesiensis Populations from French Polynesia for Chikungunya Virus.

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    Vaea Richard

    2016-05-01

    Full Text Available From October 2014 to March 2015, French Polynesia experienced for the first time a chikungunya outbreak. Two Aedes mosquitoes may have contributed to chikungunya virus (CHIKV transmission in French Polynesia: the worldwide distributed Ae. aegypti and the Polynesian islands-endemic Ae. polynesiensis mosquito.To investigate the vector competence of French Polynesian populations of Ae. aegypti and Ae. polynesiensis for CHIKV, mosquitoes were exposed per os at viral titers of 7 logs tissue culture infectious dose 50%. At 2, 6, 9, 14 and 21 days post-infection (dpi, saliva was collected from each mosquito and inoculated onto C6/36 mosquito cells to check for the presence of CHIKV infectious particles. Legs and body (thorax and abdomen of each mosquito were also collected at the different dpi and submitted separately to viral RNA extraction and CHIKV real-time RT-PCR.CHIKV infection rate, dissemination and transmission efficiencies ranged from 7-90%, 18-78% and 5-53% respectively for Ae. aegypti and from 39-41%, 3-17% and 0-14% respectively for Ae. polynesiensis, depending on the dpi. Infectious saliva was found as early as 2 dpi for Ae. aegypti and from 6 dpi for Ae. polynesiensis. Our laboratory results confirm that the French Polynesian population of Ae. aegypti is highly competent for CHIKV and they provide clear evidence for Ae. polynesiensis to act as an efficient CHIKV vector.As supported by our findings, the presence of two CHIKV competent vectors in French Polynesia certainly contributed to enabling this virus to quickly disseminate from the urban/peri-urban areas colonized by Ae. aegypti to the most remote atolls where Ae. polynesiensis is predominating. Ae. polynesiensis was probably involved in the recent chikungunya outbreaks in Samoa and the Cook Islands. Moreover, this vector may contribute to the risk for CHIKV to emerge in other Polynesian islands like Fiji, and more particularly Wallis where there is no Ae. aegypti.

  7. New Candidates for Plant-Based Repellents Against Aedes aegypti.

    Science.gov (United States)

    Misni, Norashiqin; Nor, Zurainee Mohamed; Ahmad, Rohani

    2016-06-01

    Based on an ethnobotanical study on use for plant species against mosquito bites in the Kota Tinggi District, Johor State, Malaysia, 3 plants selected for study, Citrus aurantifolia (leaves), Citrus grandis (fruit peel), and Alpinia galanga (rhizome), were extracted using hydrodistillation to produce essential oils. These essential oils were then formulated as a lotion using a microencapsulation process and then tested for their repellent effect against Aedes aegypti. N,N-diethyl-m-toluamide (deet) was also prepared in the same formulation and tested for repellency as controls. Four commercial plant-based repellent (KAPS(®), MozAway(®), BioZ Natural(®), and Mosiquard(®)) also were incorporated in the bioassay for comparison purposes. Bioassays revealed that at 20% concentration all repellent formulations demonstrated complete protection for 2 h and >90% for 4 h post-application. The A. galanga-based formulation provided the greatest level of protection (98.91%), which extended for 4 h post-application and was not significantly different from deet at similar concentration. When compared with commercial plant-based repellents (KAPS(®), MozAway(®), and BioZ Natural(®)), the 3 lotion formulations showed significantly better protection against Ae. aegypti bites, providing >90% protection for 4 h. In conclusion, our 3 plant-based lotion formulations provided acceptable levels of protection against host-seeking Ae. aegypti and should be developed. PMID:27280349

  8. Macroclimate determines the global range limit of Aedes aegypti.

    Science.gov (United States)

    Capinha, César; Rocha, Jorge; Sousa, Carla A

    2014-09-01

    Aedes aegypti is the main vector of dengue and a number of other diseases worldwide. Because of the domestic nature of this mosquito, the relative importance of macroclimate in shaping its distribution has been a controversial issue. We have captured here the worldwide macroclimatic conditions occupied by A. aegypti in the last century. We assessed the ability of this information to predict the species' observed distribution using supra-continental spatially-uncorrelated data. We further projected the distribution of the colonized climates in the near future (2010-2039) under two climate-change scenarios. Our results indicate that the macroclimate is largely responsible for setting the maximum range limit of A. aegypti worldwide and that in the near future, relatively wide areas beyond this limit will receive macroclimates previously occupied by the species. By comparing our projections, with those from a previous model based strictly on species-climate relationships (i.e., excluding human influence), we also found support for the hypothesis that much of the species' range in temperate and subtropical regions is being sustained by artificial environments. Altogether, these findings suggest that, if the domestic environments commonly exploited by this species are available in the newly suitable areas, its distribution may expand considerably in the near future. PMID:24643859

  9. Insights into the transcriptome of oenocytes from Aedes aegypti pupae

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    Gustavo Ferreira Martins

    2011-05-01

    Full Text Available Oenocytes are ectodermic cells present in the fat body of several insect species and these cells are considered to be analogous to the mammalian liver, based on their role in lipid storage, metabolism and secretion. Although oenocytes were identified over a century ago, little is known about their messenger RNA expression profiles. In this study, we investigated the transcriptome of Aedes aegypti oenocytes. We constructed a cDNA library from Ae. aegypti MOYO-R strain oenocytes collected from pupae and randomly sequenced 687 clones. After sequences editing and assembly, 326 high-quality contigs were generated. The most abundant transcripts identified corresponded to the cytochrome P450 superfamily, whose members have roles primarily related to detoxification and lipid metabolism. In addition, we identified 18 other transcripts with putative functions associated with lipid metabolism. One such transcript, a fatty acid synthase, is highly represented in the cDNA library of oenocytes. Moreover, oenocytes expressed several immunity-related genes and the majority of these genes were lysozymes. The transcriptional profile suggests that oenocytes play diverse roles, such as detoxification and lipid metabolism, and increase our understanding of the importance of oenocytes in Ae. aegypti homeostasis and immune competence.

  10. Differential Susceptibilities of Aedes aegypti and Aedes albopictus from the Americas to Zika Virus.

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    Thais Chouin-Carneiro

    2016-03-01

    Full Text Available Since the major outbreak in 2007 in the Yap Island, Zika virus (ZIKV causing dengue-like syndromes has affected multiple islands of the South Pacific region. In May 2015, the virus was detected in Brazil and then spread through South and Central America. In December 2015, ZIKV was detected in French Guiana and Martinique. The aim of the study was to evaluate the vector competence of the mosquito spp. Aedes aegypti and Aedes albopictus from the Caribbean (Martinique, Guadeloupe, North America (southern United States, South America (Brazil, French Guiana for the currently circulating Asian genotype of ZIKV isolated from a patient in April 2014 in New Caledonia.Mosquitoes were orally exposed to an Asian genotype of ZIKV (NC-2014-5132. Upon exposure, engorged mosquitoes were maintained at 28° ± 1 °C, a 16h:8h light:dark cycle and 80% humidity. 25-30 mosquitoes were processed at 4, 7 and 14 days post-infection (dpi. Mosquito bodies (thorax and abdomen, heads and saliva were analyzed to measure infection, dissemination and transmission, respectively. High infection but lower disseminated infection and transmission rates were observed for both Ae. aegypti and Ae. albopictus. Ae. aegypti populations from Guadeloupe and French Guiana exhibited a higher dissemination of ZIKV than the other Ae. aegypti populations examined. Transmission of ZIKV was observed in both mosquito species at 14 dpi but at a low level.This study suggests that although susceptible to infection, Ae. aegypti and Ae. albopictus were unexpectedly low competent vectors for ZIKV. This may suggest that other factors such as the large naïve population for ZIKV and the high densities of human-biting mosquitoes contribute to the rapid spread of ZIKV during the current outbreak.

  11. Effect of the chitin synthesis inhibitor triflumuron on the development, viability and reproduction of Aedes aegypti

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    Thiago Affonso Belinato

    2009-02-01

    Full Text Available The control of Aedes aegypti is impaired due to the development of resistance to chemical insecticides. Insect Growth Regulators (IGR exhibit distinct mechanisms of action and are considered potential vector control alternatives. Studies regarding the effects of sublethal IGR doses on the viability of resulting adults will contribute to eval-uating their impact in the field. We analyzed several aspects of Ae. aegypti adults surviving exposure to a partially lethal dose of triflumuron, a chitin synthesis inhibitor. A highly significant difference in the proportion of males and females was noted in the triflumuron-exposed group (65.0% males compared to the controls (50.2% males. Triflumuron affected adult longevity, particularly for females; after 16 days, only 29.2% of males and 13.8% of females were alive, in contrast with 94% survival of the control mosquitoes. The locomotor activity was reduced and the blood-feeding ability of the treated females was also affected (90.4% and 48.4% of the control and triflumuron-exposed females, respectively, successfully ingested blood. Triflumuron-surviving females ingested roughly 30% less blood and laid 25% fewer eggs than the control females. The treated males and females exhibited a diminished ability to copulate, resulting in less viable eggs.

  12. Effect of the chitin synthesis inhibitor triflumuron on the development, viability and reproduction of Aedes aegypti.

    Science.gov (United States)

    Belinato, Thiago Affonso; Martins, Ademir Jesus; Lima, José Bento Pereira; Lima-Camara, Tamara Nunes de; Peixoto, Alexandre Afrânio; Valle, Denise

    2009-02-01

    The control of Aedes aegypti is impaired due to the development of resistance to chemical insecticides. Insect Growth Regulators (IGR) exhibit distinct mechanisms of action and are considered potential vector control alternatives. Studies regarding the effects of sublethal IGR doses on the viability of resulting adults will contribute to eval-uating their impact in the field. We analyzed several aspects of Ae. aegypti adults surviving exposure to a partially lethal dose of triflumuron, a chitin synthesis inhibitor. A highly significant difference in the proportion of males and females was noted in the triflumuron-exposed group (65.0% males) compared to the controls (50.2% males). Triflumuron affected adult longevity, particularly for females; after 16 days, only 29.2% of males and 13.8% of females were alive, in contrast with 94% survival of the control mosquitoes. The locomotor activity was reduced and the blood-feeding ability of the treated females was also affected (90.4% and 48.4% of the control and triflumuron-exposed females, respectively, successfully ingested blood). Triflumuron-surviving females ingested roughly 30% less blood and laid 25% fewer eggs than the control females. The treated males and females exhibited a diminished ability to copulate, resulting in less viable eggs. PMID:19274375

  13. Contact irritant responses of Aedes aegypti Using sublethal concentration and focal application of pyrethroid chemicals.

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    Hortance Manda

    Full Text Available BACKGROUND: Previous studies have demonstrated contact irritant and spatial repellent behaviors in Aedes aegypti following exposure to sublethal concentrations of chemicals. These sublethal actions are currently being evaluated in the development of a push-pull strategy for Ae. aegypti control. This study reports on mosquito escape responses after exposure to candidate chemicals for a contact irritant focused push-pull strategy using varying concentrations and focal application. METHODS: Contact irritancy (escape behavior, knockdown and 24 hour mortality rates were quantified in populations of female Ae. aegypti under laboratory conditions and validated in the field (Thailand and Peru using experimental huts. Evaluations were conducted using varying concentrations and treatment surface area coverage (SAC of three pyrethroid insecticides: alphacypermethrin, lambacyhalothrin and deltamethrin. RESULTS: Under laboratory conditions, exposure of Ae. aegypti to alphacypermethrin using the standard field application rate (FAR resulted in escape responses at 25% and 50% SAC that were comparable with escape responses at 100% SAC. Significant escape responses were also observed at <100% SAC using ½FAR of all test compounds. In most trials, KD and 24 hour mortality rates were higher in mosquitoes that did not escape than in those that escaped. In Thailand, field validation studies indicated an early time of exit (by four hours and 40% increase in escape using ½FAR of alphacypermethrin at 75% SAC compared to a matched chemical-free control. In Peru, however, the maximum increase in Ae. aegypti escape from alphacypermethrin-treated huts was 11%. CONCLUSIONS/SIGNIFICANCE: Results presented here suggest a potential role for sublethal and focal application of contact irritant chemicals in an Ae. aegypti push-pull strategy to reduce human-vector contact inside treated homes. However, the impact of an increase in escape response on dengue virus transmission is

  14. Discriminable roles of Aedes aegypti and Aedes albopictus in establishment of dengue outbreaks in Taiwan.

    Science.gov (United States)

    Yang, Chao-Fu; Hou, Jion-Nun; Chen, Tien-Huang; Chen, Wei-June

    2014-02-01

    Aedes aegypti and Aedes albopictus were reported to be significant as vectors of dengue fever. In Taiwan, the latter is distributed throughout the island while the former appears only south of the Tropic of Cancer; i.e., 23.5°N. In the past decade, there were five outbreaks with over 1000 cases of dengue fever in Taiwan. Without exception, these outbreaks all occurred in the south where the two Aedes mosquitoes are sympartic. According to the Center for Disease Control of Taiwan, imported cases are thought to provide the seeds of dengue outbreaks every year. Mostly, the number of imported cases is greater in northern island, probably due to a larger population of travelers and imported workers from endemic countries. Looking at the example in 2002, northern, central, and southern parts of Taiwan reported 28, 11, and 13 imported cases, respectively. However, 54, 21, and 5309 total cases were confirmed in the corresponding regions over the entire year, indicating a significant skew of case distributions. A hypothesis is thus inspired that the existence of Ae. aegypti is a prerequisite to initiate a dengue outbreak, while participation of Ae. albopictus expands or maintains the scale until the de novo herd immunity reaches high level.

  15. Oviposition site selection by the dengue vector Aedes aegypti and its implications for dengue control.

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    Jacklyn Wong

    Full Text Available BACKGROUND: Because no dengue vaccine or antiviral therapy is commercially available, controlling the primary mosquito vector, Aedes aegypti, is currently the only means to prevent dengue outbreaks. Traditional models of Ae. aegypti assume that population dynamics are regulated by density-dependent larval competition for food and little affected by oviposition behavior. Due to direct impacts on offspring survival and development, however, mosquito choice in oviposition site can have important consequences for population regulation that should be taken into account when designing vector control programs. METHODOLOGY/PRINCIPAL FINDINGS: We examined oviposition patterns by Ae. aegypti among 591 naturally occurring containers and a set of experimental containers in Iquitos, Peru. Using larval starvation bioassays as an indirect measure of container food content, we assessed whether females select containers with the most food for their offspring. Our data indicate that choice of egg-laying site is influenced by conspecific larvae and pupae, container fill method, container size, lid, and sun exposure. Although larval food positively influenced oviposition, our results did not support the hypothesis that females act primarily to maximize food for larvae. Females were most strongly attracted to sites containing immature conspecifics, even when potential competitors for their progeny were present in abundance. CONCLUSION/SIGNIFICANCE: Due to strong conspecific attraction, egg-laying behavior may contribute more to regulating Ae. aegypti populations than previously thought. If highly infested containers are targeted for removal or larvicide application, females that would have preferentially oviposited in those sites may instead distribute their eggs among other suitable, previously unoccupied containers. Strategies that kill mosquitoes late in their development (i.e., insect growth regulators that kill pupae rather than larvae will enhance vector

  16. Resistance Status of Aedes aegypti to Cypermethrin through Susceptibility Method in Cimahi City

    OpenAIRE

    Yuneu Yuliasih; Rina Marina; Mara Ipa; Firda Yanuar Pradani

    2011-01-01

    Vector control of dengue usually doing by using insecticides, whether by government or insecticides used in household. Using to much insecticides for long time can caused resistence of mosquito. This research aim to know resistance status of Aedes aegypti from endemic rural in district Cimahi to cypermethrin (synthetic pyretroid). Resistance status knowing by susceptibility methods (WHO standard) with using impregnated paper that containing cypermethrin 0.2% and 0.4%. Aedes aegypti spread by ...

  17. Insecticide susceptibility of Aedes aegypti populations from Senegal and Cape Verde Archipelago

    OpenAIRE

    Dia Ibrahima; Diagne Cheikh; Ba Yamar; Diallo Diawo; Konate Lassana; Diallo Mawlouth

    2012-01-01

    Abstract Background Two concomitant dengue 3 (DEN-3) epidemics occurred in Cape Verde Archipelago and Senegal between September and October 2009. Aedes aegypti was identified as the vector of these epidemics as several DEN-3 virus strains were isolated from this species in both countries. The susceptibility to pyrethroids, organochlorine, organophosphates and carbamate was investigated in two field strains of Aedes aegypti from both countries using WHO diagnostic bioassay kits in order to mon...

  18. Socioeconomic and Ecological Factors Influencing Aedes aegypti Prevalence, Abundance, and Distribution in Dhaka, Bangladesh

    OpenAIRE

    Dhar-Chowdhury, Parnali; Haque, C. Emdad; Lindsay, Robbin; Hossain, Shakhawat

    2016-01-01

    This study examined household risk factors and prevalence, abundance, and distribution of immature Aedes aegypti and Aedes albopictus, and their association with socioeconomic and ecological factors at urban zonal and household levels in the city of Dhaka, Bangladesh. During the 2011 monsoon, 826 households in 12 randomly selected administrative wards were surveyed for vector mosquitoes. Results revealed that the abundance and distribution of immature Ae. aegypti and Ae. albopictus, and pupae...

  19. EFEKTIFITAS EKSTRAK BUAH PARE (Momordica Charantia) DALAM MEMATIKAN JENTIK AEDES AEGYPTI

    OpenAIRE

    Ilham Syam; Esse Puji Pawenrusi

    2016-01-01

    Demam dengue dan demam berdarah dengue adalah penyakit virus yang tersebar luas di seluruh dunia terutama di daerah tropis Sumber penularan utama adalah manusia dan primata, sedang penularnya adalah nyamuk Aedes aegypti. Penelitian ini bertujuan untuk mengetahui kemampuan ekstrak buah pare (Momordica charantia) dalam mematikan jentik Aedes aegypti dengan konsentrasi 5%, 10% dan 15% dalam waktu 8 jam dengan pengamatan setiap 30 menit disetiap konsentrasinya. Metode Penelitian ini adalah Quasi ...

  20. Wolbachia Blocks Currently Circulating Zika Virus Isolates in Brazilian Aedes aegypti Mosquitoes

    OpenAIRE

    Dutra, Heverton Leandro Carneiro; Rocha, Marcele Neves; Dias, Fernando Braga Stehling; Mansur, Simone Brutman; Caragata, Eric Pearce; Moreira, Luciano Andrade

    2016-01-01

    Summary The recent association of Zika virus with cases of microcephaly has sparked a global health crisis and highlighted the need for mechanisms to combat the Zika vector, Aedes aegypti mosquitoes. Wolbachia pipientis, a bacterial endosymbiont of insect, has recently garnered attention as a mechanism for arbovirus control. Here we report that Aedes aegypti harboring Wolbachia are highly resistant to infection with two currently circulating Zika virus isolates from the recent Brazilian epide...

  1. Vector Competence of French Polynesian Aedes aegypti and Aedes polynesiensis for Zika Virus

    Science.gov (United States)

    Richard, Vaea; Paoaafaite, Tuterarii; Cao-Lormeau, Van-Mai

    2016-01-01

    Background In 2013–2014, French Polynesia experienced for the first time a Zika outbreak. Two Aedes mosquitoes may have contributed to Zika virus (ZIKV) transmission in French Polynesia: the worldwide distributed Ae. aegypti and the Polynesian islands-endemic Ae. polynesiensis mosquito. Methodology/Principal Findings To evaluate their vector competence for ZIKV, mosquitoes were infected per os at viral titers of 7 logs tissue culture infectious dose 50%. At several days post-infection (dpi), saliva was collected from each mosquito and inoculated onto C6/36 mosquito cells to check for the presence of ZIKV infectious particles. Legs and body of each mosquito were also collected and submitted separately to RNA extraction and ZIKV RT-PCR. In Ae. aegypti the infection rate was high as early as 6 dpi and the dissemination efficiency get substantial from 9 dpi while the both rates remained quite low in Ae. polynesiensis. The transmission efficiency was poor in Ae. aegypti until 14 dpi and no infectious saliva was found in Ae. polynesiensis at the time points studied. Conclusions/Significance In our experimental conditions, the late ability of the French Polynesian Ae. aegypti to transmit ZIKV added by the poor competence of Ae. polynesiensis for this virus suggest the possible contribution of another vector for the propagation of ZIKV during the outbreak, in particular in remote islands where Ae. polynesiensis is predominating. PMID:27654962

  2. Naturally Occurring Plant Compounds with Larvicidal Activity Against Aedes aegypti [Substâncias de Origem Vegetal com Atividade Larvicida Contra Aedes aegypti

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    Walmir S. Garcez

    2013-01-01

    Full Text Available The mosquito Aedes aegypti is a vector that carries the arboviroses responsible for dengue and dengue hemorrhagic fevers, diseases which are considered as major worldwide public health problems. The most widely adopted strategy for decreasing the incidence of these diseasesresides in controlling the mosquito larvae population. The increasingly incidence of resistant mosquito populations due to the continuous use of synthetic insecticides, in addition to the publicconcern over environmental pollution and toxicity of the current commercial pesticides to non-target organisms, have stimulated the search for alternative methods for mosquito control. In this regard, plant-derived compounds have emerged as a promising efficient and environmentally safe tool for reducing the larval population ofAedes aegypti mosquitoes. This review provides a survey on naturally occurring plant compounds belonging to different classes of secondary metabolites which have been shown to be active against Aedes aegypti.

  3. INDEKS ENTOMOLOGI DAN KERENTANAN LARVA Aedes aegypti TERHADAP TEMEFOS DI KELURAHAN KARSAMENAK KECAMATAN KAWALU KOTA TASIKMALAYA

    OpenAIRE

    Hubullah Fuadzy; Joni Hendri

    2015-01-01

    AbstrakSalah satu upaya pengendalian vektor nyamuk Aedes aegypti adalah menggunakan larvasida sintetis seperti temefos. Pemanfaatan temefos secara terus menerus dan berulang merupakan faktor risiko terjadinya resistensi. Tujuan penelitian ini adalah untuk menentukan indeks entomologi dan status kerentanan larva Ae. aegypti terhadap temefos di Kelurahan Karsamenak Kecamatan Kawalu Kota Tasikmalaya. Jenis penelitian adalah eksperimen dengan rancangan acak lengkap. Populasi adalah larva nyamuk A...

  4. Dynamics of the "popcorn" Wolbachia infection in outbred Aedes aegypti informs prospects for mosquito vector control.

    Science.gov (United States)

    Yeap, H L; Mee, P; Walker, T; Weeks, A R; O'Neill, S L; Johnson, P; Ritchie, S A; Richardson, K M; Doig, C; Endersby, N M; Hoffmann, A A

    2011-02-01

    Forty percent of the world's population is at risk of contracting dengue virus, which produces dengue fever with a potentially fatal hemorrhagic form. The wMelPop Wolbachia infection of Drosophila melanogaster reduces life span and interferes with viral transmission when introduced into the mosquito Aedes aegypti, the primary vector of dengue virus. Wolbachia has been proposed as an agent for preventing transmission of dengue virus. Population invasion by Wolbachia depends on levels of cytoplasmic incompatibility, fitness effects, and maternal transmission. Here we characterized these traits in an outbred genetic background of a potential target population of Ae. aegypti using two crossing schemes. Cytoplasmic incompatibility was strong in this background, and the maternal transmission rate of Wolbachia was high. The infection substantially reduced longevity of infected adult females, regardless of whether adults came from larvae cultured under high or low levels of nutrition or density. The infection reduced the viability of diapausing and nondiapausing eggs. Viability was particularly low when eggs were laid by older females and when diapausing eggs had been stored for a few weeks. The infection affected mosquito larval development time and adult body size under different larval nutrition levels and densities. The results were used to assess the potential for wMelPop-CLA to invade natural populations of Ae. aegypti and to develop recommendations for the maintenance of fitness in infected mosquitoes that need to compete against field insects. PMID:21135075

  5. QTL Mapping of Genome Regions Controlling Temephos Resistance in Larvae of the Mosquito Aedes aegypti

    OpenAIRE

    Guadalupe Del Carmen Reyes-Solis; Karla Saavedra-Rodriguez; Adriana Flores Suarez; Black, William C.

    2014-01-01

    Introduction The mosquito Aedes aegypti is the principal vector of dengue and yellow fever flaviviruses. Temephos is an organophosphate insecticide used globally to suppress Ae. aegypti larval populations but resistance has evolved in many locations. Methodology/Principal Findings Quantitative Trait Loci (QTL) controlling temephos survival in Ae. aegypti larvae were mapped in a pair of F3 advanced intercross lines arising from temephos resistant parents from Solidaridad, México and temephos s...

  6. Insecticide susceptibility status of Aedes aegypti and Anopheles stephensi larvae against temephos in Delhi, India

    OpenAIRE

    Singh, R. K.; P.K.Mittal; Gaurav Kumar; Dhiman, R.C.

    2014-01-01

    Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortali...

  7. Differential transcription profiles in Aedes aegypti detoxification genes following temephos selection

    OpenAIRE

    Saavedra-Rodriguez, Karla; Strode, Clare; FLORES, ADRIANA E.; Garcia-Luna, Selene; Reyes-Solis, Guadalupe; Ranson, Hilary; Hemingway, Janet; Black, William C.

    2013-01-01

    The mosquito Aedes aegypti is the main vector of Dengue and Yellow Fever flaviviruses. The organophosphate insecticide temephos is a larvicide that is used globally to control Ae. aegypti populations; many of which have in turn evolved resistance. Target site alteration in the acetylcholine esterase of this species has not being identified. Instead, we tracked changes in transcription of metabolic detoxification genes using the Ae. aegypti ‘Detox Chip’ microarray during five generations of te...

  8. KERENTANAN LARVA AEDES AEGYPTI TERHADAP TEMEFOS DI TIGA KELURAHAN ENDEMIS DEMAM BERDARAH DENGUE KOTA SUKABUMI

    OpenAIRE

    Hubullah Fuadzy; Dewi Nur Hodijah; Asep Jajang; Mutiara Widawati

    2015-01-01

    AbstractResistance of Aedes aegypti larvae against temephos influeneed the efforts of Dengue Fever vector control . The purpose of this study was to determine the status of susceptibility of Ae. aegypti larvae against temephos in three Dengue Fever endemic areas in Sukabumi. Design laboratory experiment with random design. approach group. Sample of Ae. aegypti larvae instar 3 and 4 had been taken from Subdistrict Baros, Sriwedari, Nangeleng. Susceptibility test, in performed according to Worl...

  9. Genome-engineering with CRISPR-Cas9 in the mosquito Aedes aegypti

    OpenAIRE

    Kathryn E. Kistler; Leslie B. Vosshall; Benjamin J. Matthews

    2015-01-01

    The mosquito Aedes aegypti is a potent vector of the chikungunya, yellow fever, and dengue viruses, responsible for hundreds of millions of infections and over 50,000 human deaths per year. Mutagenesis in Ae. aegypti has been established with TALENs, ZFNs, and homing endonucleases, which require the engineering of DNA-binding protein domains to provide genomic target sequence specificity. Here, we describe the use of the CRISPR-Cas9 system to generate site-specific mutations in Ae. aegypti. T...

  10. Analisis faktor-faktor yang berhubungan dengan keberadaan jentik Aedes aegypti di Puskesmas III Denpasar Selatan

    OpenAIRE

    Ida Bagus Ekaputra

    2014-01-01

    The Community Health Center (CHC) III of South Denpasar is one of the endemic areas of Dengue Hemorrhagic Fever (DHF) in Denpasar, Bali Province. Dengue morbidity rate was high (>55 per 100,000 population), while the Percentage of Larvae Free Rate (PLFR) was low (<95%). This study was aimed at discovering the relationship between community's knowledge, attitude, behavior of Aedes aegypti (Ae. aegypti) larvae eradication and environmental health with the existence of Ae. aegypti larvae i...

  11. Resistance of Aedes aegypti from the state of São Paulo, Brazil, to organophosphates insecticides

    OpenAIRE

    Macoris Maria de Lourdes G; Andrighetti Maria Teresa M; Takaku Luiz; Glasser Carmen M; Garbeloto Vanessa C; Bracco José Eduardo

    2003-01-01

    Since the reintroduction of Aedes aegypti in the state of São Paulo, in the middle of the 1980-decade, organophosphate insecticides are being used to control the dengue vector. In 1996, an annual program for monitoring the susceptibility of Ae. aegypti to the insecticides was implemented. Some of the results of this monitoring program are presented. Ae. aegypti populations from ten localities have been submitted to bioassays with the diagnostic dose of temephos and fenitrothion. Only two (Mar...

  12. Sublethal effects of atrazine and glyphosate on life history traits of Aedes aegypti and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Bara, Jeffrey J; Montgomery, Allison; Muturi, Ephantus J

    2014-08-01

    Although exposure of mosquito larvae to agricultural chemicals such as herbicides is common and widespread, our understanding of how these chemicals affect mosquito ecology and behavior is limited. This study investigated how an environmentally relevant concentration of two herbicides, atrazine and glyphosate, affects mosquito life history traits. One hundred and fifty (150) first instar Aedes (Stegomyia) aegypti (L.) or Aedes (Stegomyia) albopictus (Skuse) larvae were reared in 1.6 L of live oak leaf (Quercus virginiana) infusion in the presence (5 mg/L) or absence (0 mg/L) of atrazine or glyphosate. The containers were monitored daily to determine the emergence rates, sex ratio, male and female emergence times, and female body size. Emergence rates of A. aegypti from atrazine treatment were significantly higher relative to either glyphosate or control treatments (A. aegypti: atrazine = 93 ± 6% (±95% CI), glyphosate = 82 ± 5%, control = 78 ± 5%), while emergence rates of A. albopictus in atrazine treatments were significantly higher than in glyphosate treatments but not in controls (A. albopictus: atrazine = 84 ± 5 %, glyphosate = 76 ± 4%, control = 78 ± 4%). For both mosquito species, a sex ratio distortion with male bias was observed in control and glyphosate treatments, but not in atrazine treatments (A. aegypti: atrazine = 0.90 ± 0.17 (±SE), glyphosate = 1.63 ± 0.21, control = 1.69 ± 0.26; A. albopictus: atrazine = 1.09 ± 0.08, glyphosate = 1.88 ± 0.12, control = 1.37 ± 0.11). Emergence times for both sexes of the two mosquito species were significantly longer in atrazine treatments compared to glyphosate or control treatments (A. aegypti: females: atrazine = 11.20 ± 0.50 (days ± 95 % CI), glyphosate = 9.71 ± 0.23, control = 9.87 ± 0.21; males: atrazine = 9.46 ± 0.27, glyphosate = 8.80 ± 0.25, control

  13. Repellents inhibit P450 enzymes in Stegomyia (Aedes aegypti.

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    Gloria Isabel Jaramillo Ramirez

    Full Text Available The primary defence against mosquitoes and other disease vectors is often the application of a repellent. Despite their common use, the mechanism(s underlying the activity of repellents is not fully understood, with even the mode of action of DEET having been reported to be via different mechanisms; e.g. interference with olfactory receptor neurones or actively detected by olfactory receptor neurones on the antennae or maxillary palps. In this study, we discuss a novel mechanism for repellence, one of P450 inhibition. Thirteen essential oil extracts from Colombian plants were assayed for potency as P450 inhibitors, using a kinetic fluorometric assay, and for repellency using a modified World Health Organisation Pesticide Evaluations Scheme (WHOPES arm-in cage assay with Stegomyia (Aedes aegypti mosquitoes. Bootstrap analysis on the inhibition analysis revealed a significant correlation between P450-inhibition and repellent activity of the oils.

  14. Fluctuación estacional de Aedes aegypti en Chaco, Argentina Seasonal fluctuation of Aedes aegypti in Chaco Province, Argentina

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    Marina Stein

    2005-08-01

    Full Text Available OBJETIVO: Estudiar la fluctuación estacional de Aedes aegypti y correlacionar su abundancia con factores ambientales. MÉTODOS: Las colectas fueron realizadas entre octubre de 2002 y noviembre de 2003, en la ciudad de Resistencia, província del Chaco, Argentina. Fueron hechos muestreos semanales empleando ovitrampas. El número de huevos colectados fue correlacionado con la temperatura, humedad relativa ambiente, evaporación y precipitaciones registradas en dicha localidad. Se utilizó el test de correlación de Pearson con los respectivos datos climáticos semanales, realizándose correlaciones simples y múltiples. RESULTADOS: La ocurrencia de huevos fue registrada de manera discontinua, desde la última semana de octubre de 2002, hasta la última de junio de 2003, a partir de la cual no fueron encontrados hasta noviembre de 2003. Se observó un pico de abundancia (70% en noviembre y diciembre, que coincidió con el período de temperaturas altas y mayores precipitaciones. Otro pico, aunque de menor importancia, fue observado en abril y coincidió con las lluvias de otoño. Las correlaciones fueron significativas solamente para las precipitaciones acumuladas mensuales (r=0,57; POBJECTIVE: To study the seasonal fluctuation of Aedes aegypti and to correlate its abundance with climate conditions. METHODS: Samples were weekly collected in ovitraps in the city of Resistencia, Chaco Province, Argentina, between October 2002 and November 2003. The number of eggs collected was correlated with temperature, relative humidity, evaporation and rainfalls recorded. Pearson's correlation test with the respective weekly climate data was used in single and multiple correlation analyses. RESULTS: The first record of eggs took place in the last week of October 2002 and continued irregularly up to the last week of June 2003, when no more eggs were seen until November 2003. The highest peak of abundance (70% was observed in November-December 2002, which

  15. Cumulative mortality of Aedes aegypti larvae treated with compounds.

    Science.gov (United States)

    Torres, Sandra Maria; Cruz, Nadine Louise Nicolau da; Rolim, Vitor Pereira de Matos; Cavalcanti, Maria Inês de Assis; Alves, Leucio Câmara; Silva Júnior, Valdemiro Amaro da

    2014-06-01

    OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs.

  16. Cumulative mortality of Aedes aegypti larvae treated with compounds

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    Sandra Maria Torres

    2014-06-01

    Full Text Available OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae. METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI in concentrations of 0.37 ppm (PC1 and 0.06 ppm (PC2; treated with compounds of essential oils and fermented extract, 50.0% concentration (G1; treated with compounds of essential oils and fermented extract, 25.0% concentration (G2; treated with compounds of essential oils and fermented extract, 12.5% concentration (G3; and negative control group using water (NC1 and using dimethyl (NC2. The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs.

  17. Cumulative mortality of Aedes aegypti larvae treated with compounds

    Science.gov (United States)

    Torres, Sandra Maria; da Cruz, Nadine Louise Nicolau; Rolim, Vitor Pereira de Matos; Cavalcanti, Maria Inês de Assis; Alves, Leucio Câmara; da Silva, Valdemiro Amaro

    2014-01-01

    OBJECTIVE To evaluate the larvicidal activity of Azadirachta indica, Melaleuca alternifolia, carapa guianensis essential oils and fermented extract of Carica papaya against Aedes aegypti (Linnaeus, 1762) (Diptera: Culicidae). METHODS The larvicide test was performed in triplicate with 300 larvae for each experimental group using the third larval stage, which were exposed for 24h. The groups were: positive control with industrial larvicide (BTI) in concentrations of 0.37 ppm (PC1) and 0.06 ppm (PC2); treated with compounds of essential oils and fermented extract, 50.0% concentration (G1); treated with compounds of essential oils and fermented extract, 25.0% concentration (G2); treated with compounds of essential oils and fermented extract, 12.5% concentration (G3); and negative control group using water (NC1) and using dimethyl (NC2). The larvae were monitored every 60 min using direct visualization. RESULTS No mortality occurred in experimental groups NC1 and NC2 in the 24h exposure period, whereas there was 100% mortality in the PC1 and PC2 groups compared to NC1 and NC2. Mortality rates of 65.0%, 50.0% and 78.0% were observed in the groups G1, G2 and G3 respectively, compared with NC1 and NC2. CONCLUSIONS The association between three essential oils from Azadirachta indica, Melaleuca alternifolia, Carapa guianensis and fermented extract of Carica papaya was efficient at all concentrations. Therefore, it can be used in Aedes aegypti Liverpool third larvae stage control programs. PMID:25119939

  18. Oviposition by Aedes aegypti and Aedes albopictus: influence of congeners and of oviposition site characteristics.

    Science.gov (United States)

    Rey, Jorge R; O'Connell, Sheila M

    2014-06-01

    We investigated the oviposition behavior of Ae. aegypti and Ae. albopictus. In particular we examined whether small-scale site characteristics and the presence of conspecifics or congeners altered oviposition by these mosquitoes. Various combinations of females of the two species were allowed to oviposit inside cages among either vegetation (potted plants) or structural components (wood and concrete blocks). Numbers of eggs deposited per female were compared between species, sides, and treatments. Most significant differences between treatments and species involved differences between single species and mixed species treatments. Ae. aegypti deposited more eggs/female in the vegetation side than in the structure side whereas the opposite pattern was evident for Ae. albopictus. Ae. aegypti females had higher frequency of skip oviposition than Ae. albopictus. An average of 63% of the containers in the two-species treatments contained eggs of both species, with more frequent joint occurrences observed in the treatment with three females of each species than in the treatments with one of each. Our results point to the existence of various interactions between gravid Ae. aegypti and Ae. albopictus females at or near the oviposition sites but further experimental work is necessary to fully characterize the interactions and their specific mechanisms. PMID:24820572

  19. Susceptibility profile of Aedes aegypti from Santiago Island, Cabo Verde, to insecticides.

    Science.gov (United States)

    Rocha, Hélio Daniel Ribeiro; Paiva, Marcelo Henrique Santos; Silva, Norma Machado; de Araújo, Ana Paula; Camacho, Denise dos Reis da Rosa de Azevedo; Moura, Aires Januário Fernandes da; Gómez, Lara Ferrero; Ayres, Constância Flávia Junqueira; Santos, Maria Alice Varjal de Melo

    2015-12-01

    In 2009, Cabo Verde diagnosed the first dengue cases, with 21,137 cases reported and Aedes aegypti was identified as the vector. Since the outbreak, chemical insecticides and source reduction were used to control the mosquito population. This study aimed to assess the susceptibility of A. aegypti populations from Santiago, Cabo Verde to insecticides and identify the mechanisms of resistance. Samples of A. aegypti eggs were obtained at two different time periods (2012 and 2014), using ovitraps in different locations in Santiago Island to establish the parental population. F1 larvae were exposed to different concentrations of insecticides (Bacillus thuringiensis var israelensis (Bti), diflubenzuron and temephos) to estimate the lethal concentrations (LC90) and calculate the respective rate of resistance (RR90). Semi-field tests using temephos-ABATE(®) were performed to evaluate the persistence of the product. Bottle tests using female mosquitoes were carried out to determine the susceptibility to the adulticides malathion, cypermethrin and deltamethrin. Biochemical and molecular tests were performed to investigate the presence of metabolic resistance mechanisms, associated with the enzymes glutathione S-transferases (GSTs), esterases and mixed-function oxidases (MFO) and to detect mutations or alterations in the sodium channel and acetylcholinesterase genes. A. aegypti mosquitoes from Santiago exhibited resistance to deltamethrin, cypermethrin (mortalityinsecticides used for vector control, deltamethrin and temephos. To our knowledge, this is the first report of temephos resistance in an African A. aegypti population. The low level of temephos resistance was maintained from 2012-2014, which suggested the imposition of selective pressure, although it was not possible to identify the resistance mechanisms involved. These data show that the potential failures in the local mosquito control program are not associated with insecticide resistance.

  20. Larvicidal activity against Aedes aegypti of pacharin from Bauhinia acuruana.

    Science.gov (United States)

    da Silva Góis, Roberto Wagner; de Sousa, Leôncio Mesquita; Santiago, Gilvandete Maria Pinheiro; Romero, Nirla Rodrigues; Lemos, Telma Leda Gomes; Arriaga, Angela Martha Campos; Braz-Filho, Raimundo

    2013-07-01

    The aim of the present study was to evaluate the activity of pacharin isolated from the ethanol extract from roots of Bauhinia acuruana on third-instar larvae of Aedes aegypti Linn. (Diptera: Culicidae). The crude ethanol extract showed larvicidal activity at the concentration of 500 μg/mL. Given this larvicidal activity, this extract was submitted to chromatographic fractionation on a silica gel column eluted with n-hexane, dichloromethane, ethyl ether, ethyl acetate, and methanol in order to isolate the active compound(s). Pacharin, obtained in pure form from fraction eluted with ethyl ether, was evaluated for their larvicidal effects against A. aegypti. In these bioassays, the larvae were exposed at concentrations of 500, 250, 100, 50, and 25 μg/mL of the crude ethanol extract or pacharin. After 24 h, the number of dead larvae was counted and the LC₅₀ values for larval mortality were calculated. Pacharin showed LC50 value of 78.9 ± 1.8 μg/mL. The structure of isolated compound was identified on the basis of their spectral data (IR, 1D- and 2D-NMR) and by comparison with literature spectral data. The results indicate pacharin as a potential natural larvicide.

  1. Horizontal gene transfer between Wolbachia and the mosquito Aedes aegypti

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    Walker Thomas

    2009-01-01

    Full Text Available Abstract Background The evolutionary importance of horizontal gene transfer (HGT from Wolbachia endosymbiotic bacteria to their eukaryotic hosts is a topic of considerable interest and debate. Recent transfers of genome fragments from Wolbachia into insect chromosomes have been reported, but it has been argued that these fragments may be on an evolutionary trajectory to degradation and loss. Results We have discovered a case of HGT, involving two adjacent genes, between the genomes of Wolbachia and the currently Wolbachia-uninfected mosquito Aedes aegypti, an important human disease vector. The lower level of sequence identity between Wolbachia and insect, the transcription of all the genes involved, and the fact that we have identified homologs of the two genes in another Aedes species (Ae. mascarensis, suggest that these genes are being expressed after an extended evolutionary period since horizontal transfer, and therefore that the transfer has functional significance. The association of these genes with Wolbachia prophage regions also provides a mechanism for the transfer. Conclusion The data support the argument that HGT between Wolbachia endosymbiotic bacteria and their hosts has produced evolutionary innovation.

  2. Oviposition-Stimulant and Ovicidal Activities of Moringa oleifera Lectin on Aedes aegypti

    Science.gov (United States)

    Santos, Nataly Diniz de Lima; de Moura, Kézia Santana; Napoleão, Thiago Henrique; Santos, Geanne Karla Novais; Coelho, Luana Cassandra Breitenbach Barroso; Navarro, Daniela Maria do Amaral Ferraz; Paiva, Patrícia Maria Guedes

    2012-01-01

    Background Natural insecticides against the vector mosquito Aedes aegypti have been the object of research due to their high level of eco-safety. The water-soluble Moringa oleifera lectin (WSMoL) is a larvicidal agent against A. aegypti. This work reports the effects of WSMoL on oviposition and egg hatching of A. aegypti. Methodology/Principal Findings WSMoL crude preparations (seed extract and 0–60 protein fraction), at 0.1 mg/mL protein concentration, did not affect oviposition, while A. aegypti gravid females laid their eggs preferentially (73%) in vessels containing isolated WSMoL (0.1 mg/mL), compared with vessels containing only distilled water (control). Volatile compounds were not detected in WSMoL preparation. The hatchability of fresh eggs deposited in the solutions in the oviposition assay was evaluated. The numbers of hatched larvae in seed extract, 0–60 protein fraction and WSMoL were 45±8.7 %, 20±11 % and 55±7.5 %, respectively, significantly (pactivity was also assessed using stored A. aegypti eggs. The protein concentrations able to reduce the hatching rate by 50% (EC50) were 0.32, 0.16 and 0.1 mg/mL for seed extract, 0–60 protein fraction and WSMoL, respectively. The absence of hatching of stored eggs treated with WSMoL at 0.3 mg/mL (EC99) after transfer to medium without lectin indicates that embryos within the eggs were killed by WSMoL. The reduction in hatching rate of A. aegypti was not linked to decrease in bacteria population. Conclusions/Significance WSMoL acted both as a chemical stimulant cue for ovipositing females and ovicidal agent at a given concentration. The oviposition-stimulant and ovicidal activities, combined with the previously reported larvicidal activity, make WSMoL a very interesting candidate in integrated A. aegypti control. PMID:22970317

  3. Oviposition-stimulant and ovicidal activities of Moringa oleifera lectin on Aedes aegypti.

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    Nataly Diniz de Lima Santos

    Full Text Available BACKGROUND: Natural insecticides against the vector mosquito Aedes aegypti have been the object of research due to their high level of eco-safety. The water-soluble Moringa oleifera lectin (WSMoL is a larvicidal agent against A. aegypti. This work reports the effects of WSMoL on oviposition and egg hatching of A. aegypti. METHODOLOGY/PRINCIPAL FINDINGS: WSMoL crude preparations (seed extract and 0-60 protein fraction, at 0.1 mg/mL protein concentration, did not affect oviposition, while A. aegypti gravid females laid their eggs preferentially (73% in vessels containing isolated WSMoL (0.1 mg/mL, compared with vessels containing only distilled water (control. Volatile compounds were not detected in WSMoL preparation. The hatchability of fresh eggs deposited in the solutions in the oviposition assay was evaluated. The numbers of hatched larvae in seed extract, 0-60 protein fraction and WSMoL were 45 ± 8.7 %, 20 ± 11 % and 55 ± 7.5 %, respectively, significantly (p<0.05 lower than in controls containing only distilled water (75-95%. Embryos were visualized inside fresh control eggs, but not within eggs that were laid and maintained in WSMoL solution. Ovicidal activity was also assessed using stored A. aegypti eggs. The protein concentrations able to reduce the hatching rate by 50% (EC50 were 0.32, 0.16 and 0.1 mg/mL for seed extract, 0-60 protein fraction and WSMoL, respectively. The absence of hatching of stored eggs treated with WSMoL at 0.3 mg/mL (EC99 after transfer to medium without lectin indicates that embryos within the eggs were killed by WSMoL. The reduction in hatching rate of A. aegypti was not linked to decrease in bacteria population. CONCLUSIONS/SIGNIFICANCE: WSMoL acted both as a chemical stimulant cue for ovipositing females and ovicidal agent at a given concentration. The oviposition-stimulant and ovicidal activities, combined with the previously reported larvicidal activity, make WSMoL a very interesting candidate in

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

    NARCIS (Netherlands)

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

    2001-01-01

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

  5. Dispersal of Aedes aegypti and Aedes albopictus (Diptera: Culicidae in an urban endemic dengue area in the State of Rio de Janeiro, Brazil

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    Nildimar Alves Honório

    2003-03-01

    Full Text Available Experimental releases of female Aedes (Stegomyia aegypti and Aedes (Stegomyia albopictus were performed in August and September 1999, in an urban area of Nova Iguaçu, State of Rio de Janeiro, Brazil, to estimate their flight range in a circular area of 1,600 m where 1,472 ovitraps were set. Releases of 3,055 Ae. aegypti and 2,225 Ae. albopictus females, fed with rubidium (Rb-marked blood and surgically prevented from subsequent blood-feeding, were separated by 11 days. Rb was detected in ovitrap-collected eggs by atomic emission spectrophotometry. Rb-marked eggs of both species were detected up to 800 m from the release point. Eggs of Ae. albopictus were more numerous and more heterogeneously distributed in the area than those of Ae. aegypti. Eggs positively marked for Rb were found at all borders of the study area, suggesting that egg laying also occurred beyond these limits. Results from this study suggest that females can fly at least 800 m in 6 days and, if infected, potentially spread virus rapidly.

  6. Freqüência de larvas e pupas de Aedes aegypti e Aedes albopictus em armadilhas, Brasil Frequency of Aedes aegypti and Aedes albopictus larvae and pupae in traps, Brazil

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    Nildimar Alves Honório

    2001-08-01

    Full Text Available OBJETIVO: Avaliar a freqüência mensal de larvas e pupas de Ae. albopictus, Ae. aegypti e de outras espécies de mosquitos e verificar a influência de fatores ambientais dessas espécies em pneus. MÉTODOS: A pesquisa foi desenvolvida no município de Nova Iguaçu, Estado do Rio de Janeiro, Brasil. Efetuaram-se coletas mensais de formas imaturas, em quatro pneus, no período de novembro de 1997 a outubro de 1998. Os pneus foram numerados e dispostos em forma de pirâmide, um na base (pneu 1 e os três restantes (2, 3 e 4 inclinados sobre o primeiro. Os pneus 1 e 4 eram mais sombreados, e 2 e 3 eram expostos ao sol, já que não eram alcançados, como os demais, pela sombra de árvores e de um galinheiro próximos a esses pneus. Foram estudadas as variáveis: pluviosidade; temperatura ambiente; volume; pH da água; e condições de isolamento de água em pneus. RESULTADOS: Coletaram-se 10.310 larvas e 612 pupas. Ae. albopictus foi a espécie predominante tanto na fase larvar quanto na de pupa; Ae. aegypti e Ae. albopictus foram coletados em todos os meses, sendo mais freqüentes naqueles de maior pluviosidade. A temperatura, a pluviosidade e o volume de água apresentaram diferenças significativas, quando correlacionados ao número de larvas de Ae. aegypti. Não houve diferença significativa na freqüência de larvas quanto ao pH da água. Registrou-se maior número de larvas de Ae. albopictus em pneus mais sombreados. CONCLUSÕES: Ae. albopictus instala-se muito mais freqüentemente em pneus do que Ae. aegypti. Pneus descartados parecem representar importantes focos de manutenção de ambos os Aedes, durante todo o ano. Mesmo próximo uns ao outros, os pneus podem oferecer diferentes condições para a colonização desses mosquitos, de acordo com o volume d'água e a exposição ao sol.OBJECTIVE: To evaluate the monthly frequency of larvae and pupae of Aedes albopictus, Aedes aegypti and other mosquitoe species in tires, and the influence

  7. Insecticide susceptibility of Aedes aegypti and Aedes albopictus in Central Africa

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    Nwane Philippe

    2011-05-01

    Full Text Available Abstract Background Aedes aegypti (Linnaeus, 1762 and Aedes albopictus (Skuse, 1894 are the main vectors of dengue (DENV and chikungunya (CHIKV viruses worldwide. As there is still no vaccine or specific treatment for DENV and CHIKV, vector control remains the cornerstone of prevention and outbreak control. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides in several areas through the world. Throughout Central Africa no recent data are available susceptible/resistant status of either vector species since the introduction/arrival of Ae. albopictus in this area. We therefore studied the level of resistance of these two major vectors to insecticides commonly used in Africa for mosquito control. Results Aedes aegypti and Ae. albopictus were sampled in six urban localities of Cameroon (Garoua, Bertoua, Yaoundé, Bafia, Buea and Gabon (Libreville. Larval bioassays, carried out to determine the lethal concentrations (LC50 and LC95 and resistance ratios (RR50 and RR95 suggested that both vector species were susceptible to Bti (Bacillus thuringiensis var israeliensis and temephos. Bioassays were also performed on adults using WHO diagnostic test kits to assess phenotypic resistance to deltamethrin, DDT, fenitrothion and propoxur. These experiments showed that one population of Ae. aegypti (Libreville and two populations of Ae. albopictus (Buea and Yaoundé were resistant to DDT (mortality 36% to 71%. Resistance to deltamethrin was also suspected in Ae. albopictus from Yaoundé (83% mortality. All other field mosquito populations were susceptible to deltamethrin, DDT, fenitrothion and propoxur. No increase in the knockdown times (Kdt50 and Kdt95 was noted in the Yaoundé resistant population compared to other Ae. albopictus populations, suggesting the possible involvement of metabolic resistance to deltamethrin and DDT. Conclusion In view of the recent increase in

  8. Using Wolbachia Releases to Estimate Aedes aegypti (Diptera: Culicidae) Population Size and Survival.

    Science.gov (United States)

    Garcia, Gabriela de Azambuja; Dos Santos, Lilha Maria Barbosa; Villela, Daniel Antunes Maciel; Maciel-de-Freitas, Rafael

    2016-01-01

    Mosquitoes carrying the endosymbiont bacterium Wolbachia have been deployed in field trials as a biological control intervention due to Wolbachia effects on reducing transmission of arboviruses. We performed mark, release and recapture (MRR) experiments using Wolbachia as an internal marker with daily collections with BG-Traps during the first two weeks of releases in Rio de Janeiro, Brazil. The MRR design allowed us to investigate two critical parameters that determine whether Wolbachia would successful invade a field population: the probability of daily survival (PDS) of Wolbachia-infected Aedes aegypti females, and the wild population density during releases. Released females had a PDS of 0.82 and 0.89 in the first and second weeks, respectively, immediately after releases, which is well within the range of previous estimates of survivorship of wild mosquitoes in Rio de Janeiro. Abundance estimation of wild population varied up to 10-fold higher depending on the estimation method used (634-3565 females on the average-difference model to 6365-16188 females according to Lincoln-Petersen). Wolbachia-released mosquitoes were lower than the density estimation of their wild counterparts, irrespectively of the model used. Individually screening mosquitoes for the presence of Wolbachia reduced uncertainty on abundance estimations due to fluctuation in capturing per week. A successful invasion into local population requires Ae. aegypti fitness is unaffected by Wolbachia presence, but also reliable estimates on the population size of wild mosquitoes. PMID:27479050

  9. Mosquitocidal and Oviposition Repellent Activities of the Extracts of Seaweed Bryopsis pennata on Aedes aegypti and Aedes albopictus

    OpenAIRE

    Ke-Xin Yu; Ching-Lee Wong; Rohani Ahmad; Ibrahim Jantan

    2015-01-01

    The ever-increasing threat from infectious diseases and the development of insecticide resistance in mosquito populations drive the global search for new natural insecticides. The aims of this study were to evaluate the mosquitocidal activity of the extracts of seaweed Bryopsis pennata against dengue vectors Aedes aegypti and Aedes albopictus, and determine the seaweed’s toxic effect on brine shrimp nauplii (as a non-target organism). In addition, the chemical compositions of the active larvi...

  10. Release of thiotepa sterilized males into caged populations of Aedes aegypti: life table analysis.

    Science.gov (United States)

    Gato, René; Companioni, Ariamys; Bruzón, Rosa Y; Menéndez, Zulema; González, Aileen; Rodríguez, Misladys

    2014-04-01

    Successful SIT trials against mosquitoes in the 1960-70s were achieved by sterilizing male mosquitoes using chemosterilants. Their use was discontinued after concerns were raised about the effect of residues on non-target organisms, although scant evidence has been published. Irradiation is an expensive process; chemosterilization could be an affordable option for implementing SIT programs in developing countries. We compare life table parameters of three Aedes aegypti populations comprising different ratios of thiotepa-treated and non-treated males in order to identify the impact on reproductive potential of the presence of sterile males. No difference was observed in the survival of the treated and untreated males. The release of thiotepa sterilized males into caged Ae. aegypti populations had no effect on death or survival probability of the individuals in the cages but the fecundity of females was significantly reduced, as evaluated by hatch rate and stable age structure parameters. The significant decreases in net reproduction rate, finite rate of natural increase and intrinsic rate of natural increase in populations including sterile males are sufficient to indicate that such populations would not be able to proliferate in natural conditions. This suggests that release of Ae. aegypti thiotepa-treated males could be effective in reducing the reproductive capability of the target population and consequently contribute to vector control. PMID:24513037

  11. Isolation and Characterization of Midgut Lectin From Aedes aegypti (L. (Diptera: Culicidae

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    Tahany Hassan Ayaad

    2015-12-01

    Full Text Available ABSTRACT The present investigation deals with the isolation and characterization of a lectin from Aedes aegypti (Ae aegypti female mid gut extract that agglutinates various mammalian red blood cells (RBCs such as human three groups A, B, and O (RH+, mouse, rat, guinea-pig, sheep and goat erythrocytes. The highest activity of both crude and isolated mid gut lectins were detected against sheep RBCs. Using (NH42 SO4 fractionation, ion-exchange and mannose-CNBr-Sepharose 6B affinity chromatography techniques, Ae. aegypti midgut lectin (Aelec was purified to homogeneity.Isoelectric focusing (IEF and reducing SDS/PAGE revealed that the isolated mid gut lectin had isoelectric point (PI of 5.90, and subunits approximate molecular weights of 35.50 and 27.35 KDa. The hemagglutination (HA of lectins were Ca2+ - independent and heat-resistant. The sugar specificity of the purified Aelec was strongly inhibited by D (+-mannose and raffinose, followed by D (+ glucose. N-acetyl-D-manosamine and N-acetyl-D-glucosamine were moderate inhibitors. None of the lectins were inhibited by the disaccharides such as galactose, lactose, trehalose (IC50 up to 200 mM or fetuin up to 1% but the glycosubstances mucin and laminarin were strong inhibitors up to very low concentrations (0.030 - 0.003%.

  12. Vertical infestation of the dengue vectors Aedes aegypti and Aedes albopictus in apartments in Kuala Lumpur, Malaysia.

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    Roslan, Muhammad Aidil; Shafie, Aziz; Ngui, Romano; Lim, Yvonne Ai Lian; Sulaiman, Wan Yusoff Wan

    2013-12-01

    Dengue is a serious public health problem in Malaysia. The aim of this study was to compare the vertical infestation of Aedes population in 2 apartments in Kuala Lumpur with different status of dengue incidence (i.e., high-dengue-incidence area and area with no reported dengue cases). The study was also conducted to assess the relationship between environmental factors such as rainfall, temperature, and humidity and Aedes population that may influence Aedes infestation. Surveillance with a mosquito larvae trapping device was conducted for 28 continuous weeks (January to July 2012) in Vista Angkasa (VA) and Inderaloka (IL) apartments located in Kuala Lumpur, Malaysia. The results indicated that both Aedes spp. could be found from ground to higher floor levels of the apartments, with Aedes aegypti being more predominant than Ae. albopictus. Data based on mixed and single breeding of Aedes spp. on different floors did not show any significant difference. Both rainfall (R3; i.e., the amount of rainfall collected during the previous 3 wk before the surveillance period began) and RH data showed significant relationship with the number of Aedes larvae collected in VA and IL. No significant difference was found between the numbers of Aedes larvae in both study areas as well as maximum and minimum temperatures. Results also indicated adaptations of Ae. aegypti to the ecosystem at each elevation of high-rise buildings, with Ae. albopictus staying inside of apartment units.

  13. Oviposition and flight orientation response of Aedes aegypti to certain aromatic aryl hydrazono esters.

    Science.gov (United States)

    Guha, Lopamudra; Seenivasagan, T; Bandyopadhyay, Prabal; Iqbal, S Thanvir; Sathe, Manisha; Sharma, Pratibha; Parashar, B D; Kaushik, M P

    2012-09-01

    Aedes aegypti is a day-biting, highly anthropophilic mosquito and a potential vector of dengue and chikungunya in India. A. aegypti is a container breeder, generally oviposit in the stored and fresh water bodies, and discarded containers near residential areas that provide suitable habitats for oviposition by gravid females. The diurnal activity and endophilic nature of these mosquitoes have increased the frequency of contact with human being. Assured blood meal from human host in an infested area leads to increased disease occurrence. Gravid mosquitoes can potentially be lured to attractant-treated traps and could subsequently be killed with insecticides or growth regulators. In this direction, oviposition by A. aegypti females to aryl hydrazono esters (AHE)-treated bowls at 10 ppm concentration was tested in dual choice experiment, and their orientation response to these ester compounds was studied in Y-tube olfactometer. Among the esters tested, AHE-2, AHE-11 and AHE-12 elicited increased egg deposition with oviposition activity indices (OAI) of +0.39, +0.24 and +0.48, respectively, compared to control; in contrast, AHE-8, AHE-9 and AHE-10 showed negative oviposition response with OAI of -0.46, -0.35 and -0.29, respectively, at 10 mg/L. In the Y-tube olfactometer bioassay, AHE-2 attracted 60 % females compared to control, while to the odour of AHE-11 and AHE-12, about 70 % of the females were trapped in treated chambers. In contrast, only 27-30 % of gravid females entered the chamber releasing AHE-8, AHE-9 and AHE-10 odour plumes, while 70 % entered control chamber, evincing a possible non-preference of treatment odours as well as interference with olfactory receptors. These compounds have the potential for application as oviposition stimulants or deterrents for surveillance and control of mosquito population using ovitraps.

  14. Electroantennogram, flight orientation, and oviposition responses of Aedes aegypti to the oviposition pheromone n-heneicosane.

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    Seenivasagan, T; Sharma, Kavita R; Sekhar, K; Ganesan, K; Prakash, Shri; Vijayaraghavan, R

    2009-03-01

    Oviposition pheromones specifically influence the females of many insects to lay eggs in the sites resulting in more egg deposition. A previous report describes the principal role of n-heneicosane (C(21)) identified and characterized from the larval cuticle of Aedes aegypti (L.) in attracting the gravid mosquitoes to oviposit in treated substrates among other chemical components. However, the means by which this compound is perceived by the females for oviposition has not been reported. In this study, we have recorded the peripheral olfactory responses from the antenna of Ae. aegypti from 10(-7) g to 10(-3) g doses of n-heneicosane. The EAG response of female mosquitoes increased in a dose-dependent manner with increasing stimulus strength. In the orientation assay using Y-maze olfactometer, female mosquitoes were attracted to the odor plume of 10(-6) g and 10(-5) g dose, while the higher dose of 10(-3) g plume enforced repellency to gravid mosquitoes. The response to oviposition substrates by gravid Ae. aegypti females differed across the range of concentrations of n-heneicosane under multiple choice conditions, larger number of eggs were deposited in 10 ppm (10 mg/l) solutions compared to lower and higher concentrations indicating 10 ppm was most attractive. Application of n-heneicosane at 10 ppm in breeding habitats will be a useful method to attract the gravid mosquitoes using ovitraps for surveillance and monitoring. The possible use of this compound in monitoring of mosquito population in endemic areas in relevance to integrated vector management strategies is discussed in detail.

  15. INDEKS ENTOMOLOGI DAN KERENTANAN LARVA Aedes aegypti TERHADAP TEMEFOS DI KELURAHAN KARSAMENAK KECAMATAN KAWALU KOTA TASIKMALAYA

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    Hubullah Fuadzy

    2015-10-01

    Full Text Available AbstrakSalah satu upaya pengendalian vektor nyamuk Aedes aegypti adalah menggunakan larvasida sintetis seperti temefos. Pemanfaatan temefos secara terus menerus dan berulang merupakan faktor risiko terjadinya resistensi. Tujuan penelitian ini adalah untuk menentukan indeks entomologi dan status kerentanan larva Ae. aegypti terhadap temefos di Kelurahan Karsamenak Kecamatan Kawalu Kota Tasikmalaya. Jenis penelitian adalah eksperimen dengan rancangan acak lengkap. Populasi adalah larva nyamuk Ae. aegypti yang diperoleh dari 289 rumah penduduk di Kelurahan Karsamenak, dan sampel adalah 700 larva Ae. aegypti strain Karsamenak. Bioassay menggunakan metode Elliot dan Polson dengan konsentrasi diagnostik WHO sebesar 0,02 ppm. Hasil penelitian menunjukkan bahwa House Index (HI 24,9; Container Index (CI 9,05; Breteau Index (BI 29,07; dan Density Figure (DF 4. Larva Ae. aegypti umumnya ditemukan di Bak Mandi penduduk. Kemudian untuk membunuh 95% larva Ae. aegypti dibutuhkan konsentrasi temefos sebesar (LC95 0,02416 ppm (0,01917 ­ 0,03330 ppm dan RR95 3,02. Kelurahan Karsamenak termasuk wilayah yang potensial untuk penularan penyakit Demam Berdarah Dengue, dan larva Ae. aegypti terindikasi telah resisten terhadap temefos.Kata Kunci : Resisten, Aedes aegypti, temefos, kerentananAbstractOne effort for controlling Aedes aegypti as dengue vector is using synthetic larvacide such as temephos. Utilization of temephos continuously and repeatedly a risk factor for resistance. The objective of this study were to determine the entomology index and susceptibility of Ae. aegypti larvae against temephos in endemic areas of dengue fever in the Karsamenak District Kawalu of Tasikmalaya. The research was a true experimental study with a complete randomized design. The population were the larvae of Ae. aegypti were derived from 289 houses of resident in the Village Karsamenak and the sample was 700 larvae of Ae. aegypti strains Karsamenak. The Bioassay used Elliot and

  16. Bionomics of Aedes aegypti subpopulations (Diptera: Culicidae) from Misiones Province, northeastern Argentina.

    Science.gov (United States)

    Tejerina, Edmundo Fabricio; Almeida, Francisco Felipe Ludueña; Almirón, Walter Ricardo

    2009-01-01

    Life statistics of four Aedes aegypti subpopulations from the subtropical province of Misiones were studied during autumn and winter, under semi-natural conditions, coming from the localities of Posadas (SW), San Javier (SE), Bernardo de Irigoyen (NE) and Puerto Libertad (NW). The eastern subpopulations are geographically separated by the central mountain system of the province from the western subpopulations. High percentages of larval and pupal survival (97-100%) were recorded, and no significant differences were detected among the four subpopulations. Larvae and pupae lasted approximately 8 days to complete their development, no significant differences being detected among the four subpopulations studied. Sex ratio recorded did not differ significantly from 1:1. Male longevity did not show difference among the different subpopulations, but female longevity was remarkably different among the four subpopulations (F=16.27; d.f.=(3;8); P=0.0009), ranging among 11.45 days for San Javier and 57.87 days for Posadas. Fecundity also varied considerably among subpopulations, the greatest number (307.44 eggs/female) being recorded for Posadas (F=4.13; d.f.=(3;8); P=0.04). Ae. aegypti females of the western subpopulations lived longer than the eastern subpopulations studied, therefore, the risk of dengue outbreak would be greater on the Misiones Province border with Paraguay.

  17. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina Main breeding-containers for Aedes aegypti and associated culicids, Argentina

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    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.

  18. Wolbachia-associated bacterial protection in the mosquito Aedes aegypti.

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    Yixin H Ye

    Full Text Available BACKGROUND: Wolbachia infections confer protection for their insect hosts against a range of pathogens including bacteria, viruses, nematodes and the malaria parasite. A single mechanism that might explain this broad-based pathogen protection is immune priming, in which the presence of the symbiont upregulates the basal immune response, preparing the insect to defend against subsequent pathogen infection. A study that compared natural Wolbachia infections in Drosophila melanogaster with the mosquito vector Aedes aegypti artificially transinfected with the same strains has suggested that innate immune priming may only occur in recent host-Wolbachia associations. This same study also revealed that while immune priming may play a role in viral protection it cannot explain the entirety of the effect. METHODOLOGY/FINDINGS: Here we assess whether the level of innate immune priming induced by different Wolbachia strains in A. aegypti is correlated with the degree of protection conferred against bacterial pathogens. We show that Wolbachia strains wMel and wMelPop, currently being tested for field release for dengue biocontrol, differ in their protective abilities. The wMelPop strain provides stronger, more broad-based protection than wMel, and this is likely explained by both the higher induction of immune gene expression and the strain-specific activation of particular genes. We also show that Wolbachia densities themselves decline during pathogen infection, likely as a result of the immune induction. CONCLUSIONS/SIGNIFICANCE: This work shows a correlation between innate immune priming and bacterial protection phenotypes. The ability of the Toll pathway, melanisation and antimicrobial peptides to enhance viral protection or to provide the basis of malaria protection should be further explored in the context of this two-strain comparison. This work raises the questions of whether Wolbachia may improve the ability of wild mosquitoes to survive pathogen

  19. Inheritance of Resistance to Deltamethrin in Aedes aegypti (Diptera: Culicidae) From Cuba.

    Science.gov (United States)

    Rodríguez, María Magdalena; Hurtado, Daymi; Severson, David W; Bisset, Juan A

    2014-11-01

    The development of pyrethroid resistance in Aedes aegypti (L) (Diptera: Culicidae) is a serious concern because major A. aegypti control programs are predominantly based on pyrethroid use during epidemic disease outbreaks. Research about the genetic basis for pyrethroid resistance and how it is transmitted among mosquito populations is needed. The objective of this study was to determine how deltamethrin resistance is inherited in the Cuban A. aegypti-resistant reference strain. Here, a field population of A. aegypti from Santiago de Cuba (SAN-F14), subjected to 14 generations of selection for high deltamethrin resistance level (91.25×), was used to prepare reciprocal F1 and backcross progeny with the insecticide-susceptible Rockefeller strain. Bioassays with larvae were performed according to World Health Organization guidelines. The activities of metabolic enzymes were assayed through synergist and biochemical tests. The null hypothesis of the parallelism test between the two probit regression lines of the reciprocal F1 (susceptible females × resistant males and vice versa) was not rejected at the 5% significance level (P = 0.42), indicating autosomal inheritance. The LC50 response of both F1 progenies to deltamethrin was elevated but less than the highly resistant SAN-F14 strain. DLC values for the F1 progenies were 0.91 and 0.87, respectively, suggesting that deltamethrin resistance in the SAN-F14 strain is inherited as an autosomal incompletely dominant trait, involving at least two factors, which implies a faster development of deltamethrin resistance in larvae and lost product effectiveness. Metabolic enzymes including esterases and cytochrome P-450 monooxygenases but not glutathione-S-transferases were involved in deltamethrin resistance in larvae. PMID:26309309

  20. Aedes aegypti (Diptera: Culicidae) in Mauritania: First Report on the Presence of the Arbovirus Mosquito Vector in Nouakchott.

    Science.gov (United States)

    Mint Lekweiry, Khadijetou; Ould Ahmedou Salem, Mohamed Salem; Ould Brahim, Khyarhoum; Ould Lemrabott, Mohamed Aly; Brengues, Cécile; Faye, Ousmane; Simard, Frédéric; Ould Mohamed Salem Boukhary, Ali

    2015-07-01

    Aedes aegypti L. (Diptera: Culicidae) is a major vector of yellow fever, dengue, and chikungunya viruses throughout tropical and subtropical areas of the world. Although the southernmost part of Mauritania along the Senegal river has long been recognized at risk of yellow fever transmission, Aedes spp. mosquitoes had never been reported northwards in Mauritania. Here, we report the first observation of Aedes aegypti aegypti (L.) and Aedes (Ochlerotatus) caspius (Pallas, 1771) in the capital city, Nouakchott. We describe the development sites in which larvae of the two species were found, drawing attention to the risk for emergence of arbovirus transmission in the city.

  1. Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements.

    Science.gov (United States)

    Dickson, Laura B; Sharakhova, Maria V; Timoshevskiy, Vladimir A; Fleming, Karen L; Caspary, Alex; Sylla, Massamba; Black, William C

    2016-04-01

    Aedes aegypti, the primary vector of dengue, yellow fever and Zika flaviviruses, consists of at least two subspecies. Aedes aegypti (Aaa) is light in color, has pale scales on the first abdominal tergite, oviposits in artificial containers, and preferentially feeds on humans. Aedes aegypti formosus (Aaf), has a dark cuticle, is restricted to sub-Saharan Africa, has no pale scales on the first abdominal tergite and frequently oviposits in natural containers. Scale patterns correlate with cuticle color in East Africa but not in Senegal, West Africa where black cuticle mosquitoes display a continuum of scaling patterns and breed domestically indoors. An earlier laboratory study did not indicate any pre- or postzygotic barriers to gene flow between Aaa and Aaf in East Africa. However, similar attempts to construct F1 intercross families between Aaa laboratory strains and Senegal Ae. aegypti (SenAae) failed due to poor F1 oviposition and low F2 egg-to-adult survival. Insemination and assortative mating experiments failed to identify prezygotic mating barriers. Backcrosses were performed to test for postzygotic isolation patterns consistent with Haldane's rule modified for species, like Aedes, that have an autosomal sex determining locus (SDL). Egg-pupal survival was predicted to be low in females mated to hybrid F1 males but average when a male mates with a hybrid F1 female. Survival was in fact significantly reduced when females mated to hybrid males but egg-pupal survival was significantly increased when males were mated to hybrid F1 females. These observations are therefore inconclusive with regards to Haldane's rule. Basic cytogenetic analyses and Fluorescent In Situ Hybridization (FISH) experiments were performed to compare SenAae strains with the IB12 strain of Aaa that was used for genome sequencing and physical mapping. Some SenAae strains had longer chromosomes than IB12 and significantly different centromeric indices on chromosomes 1 and 3. DAPI staining was

  2. Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements

    Science.gov (United States)

    Dickson, Laura B.; Sharakhova, Maria V.; Timoshevskiy, Vladimir A.; Fleming, Karen L.; Caspary, Alex; Sylla, Massamba; Black, William C.

    2016-01-01

    Aedes aegypti, the primary vector of dengue, yellow fever and Zika flaviviruses, consists of at least two subspecies. Aedes aegypti (Aaa) is light in color, has pale scales on the first abdominal tergite, oviposits in artificial containers, and preferentially feeds on humans. Aedes aegypti formosus (Aaf), has a dark cuticle, is restricted to sub-Saharan Africa, has no pale scales on the first abdominal tergite and frequently oviposits in natural containers. Scale patterns correlate with cuticle color in East Africa but not in Senegal, West Africa where black cuticle mosquitoes display a continuum of scaling patterns and breed domestically indoors. An earlier laboratory study did not indicate any pre- or postzygotic barriers to gene flow between Aaa and Aaf in East Africa. However, similar attempts to construct F1 intercross families between Aaa laboratory strains and Senegal Ae. aegypti (SenAae) failed due to poor F1 oviposition and low F2 egg-to-adult survival. Insemination and assortative mating experiments failed to identify prezygotic mating barriers. Backcrosses were performed to test for postzygotic isolation patterns consistent with Haldane’s rule modified for species, like Aedes, that have an autosomal sex determining locus (SDL). Egg-pupal survival was predicted to be low in females mated to hybrid F1 males but average when a male mates with a hybrid F1 female. Survival was in fact significantly reduced when females mated to hybrid males but egg-pupal survival was significantly increased when males were mated to hybrid F1 females. These observations are therefore inconclusive with regards to Haldane’s rule. Basic cytogenetic analyses and Fluorescent In Situ Hybridization (FISH) experiments were performed to compare SenAae strains with the IB12 strain of Aaa that was used for genome sequencing and physical mapping. Some SenAae strains had longer chromosomes than IB12 and significantly different centromeric indices on chromosomes 1 and 3. DAPI staining

  3. Reproductive Incompatibility Involving Senegalese Aedes aegypti (L) Is Associated with Chromosome Rearrangements.

    Science.gov (United States)

    Dickson, Laura B; Sharakhova, Maria V; Timoshevskiy, Vladimir A; Fleming, Karen L; Caspary, Alex; Sylla, Massamba; Black, William C

    2016-04-01

    Aedes aegypti, the primary vector of dengue, yellow fever and Zika flaviviruses, consists of at least two subspecies. Aedes aegypti (Aaa) is light in color, has pale scales on the first abdominal tergite, oviposits in artificial containers, and preferentially feeds on humans. Aedes aegypti formosus (Aaf), has a dark cuticle, is restricted to sub-Saharan Africa, has no pale scales on the first abdominal tergite and frequently oviposits in natural containers. Scale patterns correlate with cuticle color in East Africa but not in Senegal, West Africa where black cuticle mosquitoes display a continuum of scaling patterns and breed domestically indoors. An earlier laboratory study did not indicate any pre- or postzygotic barriers to gene flow between Aaa and Aaf in East Africa. However, similar attempts to construct F1 intercross families between Aaa laboratory strains and Senegal Ae. aegypti (SenAae) failed due to poor F1 oviposition and low F2 egg-to-adult survival. Insemination and assortative mating experiments failed to identify prezygotic mating barriers. Backcrosses were performed to test for postzygotic isolation patterns consistent with Haldane's rule modified for species, like Aedes, that have an autosomal sex determining locus (SDL). Egg-pupal survival was predicted to be low in females mated to hybrid F1 males but average when a male mates with a hybrid F1 female. Survival was in fact significantly reduced when females mated to hybrid males but egg-pupal survival was significantly increased when males were mated to hybrid F1 females. These observations are therefore inconclusive with regards to Haldane's rule. Basic cytogenetic analyses and Fluorescent In Situ Hybridization (FISH) experiments were performed to compare SenAae strains with the IB12 strain of Aaa that was used for genome sequencing and physical mapping. Some SenAae strains had longer chromosomes than IB12 and significantly different centromeric indices on chromosomes 1 and 3. DAPI staining was

  4. Age-Stage, Two-Sex Life Table Characteristics of Aedes albopictus and Aedes Aegypti in Penang Island, Malaysia.

    Science.gov (United States)

    Maimusa, Hamisu A; Ahmad, Abu Hassan; Kassim, Nur Faeza A; Rahim, Junaid

    2016-03-01

    The life table developmental attributes of laboratory colonies of wild strains of Aedes albopictus and Aedes aegypti were analyzed and compared based on the age-stage, two-sex life table. Findings inclusive in this study are: adult preoviposition periods, total preoviposition period, mean intrinsic rate of increase (r), mean finite rate of increase (λ), net reproductive rates (R0), and mean generation time (T). The total preadult development time was 9.47 days for Ae. albopictus and 8.76 days for Ae. aegypti. The life expectancy was 19.01 days for Ae. albopictus and 19.94 days for Ae. aegypti. Mortality occurred mostly during the adult stage. The mean development time for each stage insignificantly correlated with temperature for Ae. albopictus (r  =  -0.208, P > 0.05) and (r  =  -0.312, P > 0.05) for Ae. aegypti. The population parameters suggest that Ae. albopictus and Ae. aegypti populations are r-strategists characterized by a high r, a large R0, and short T. This present study provides the first report to compare the life parameters of Ae. albopictus and Ae. aegypti strains from Penang island, Malaysia.

  5. Susceptibility profile of Aedes aegypti from Santiago Island, Cabo Verde, to insecticides.

    Science.gov (United States)

    Rocha, Hélio Daniel Ribeiro; Paiva, Marcelo Henrique Santos; Silva, Norma Machado; de Araújo, Ana Paula; Camacho, Denise dos Reis da Rosa de Azevedo; Moura, Aires Januário Fernandes da; Gómez, Lara Ferrero; Ayres, Constância Flávia Junqueira; Santos, Maria Alice Varjal de Melo

    2015-12-01

    In 2009, Cabo Verde diagnosed the first dengue cases, with 21,137 cases reported and Aedes aegypti was identified as the vector. Since the outbreak, chemical insecticides and source reduction were used to control the mosquito population. This study aimed to assess the susceptibility of A. aegypti populations from Santiago, Cabo Verde to insecticides and identify the mechanisms of resistance. Samples of A. aegypti eggs were obtained at two different time periods (2012 and 2014), using ovitraps in different locations in Santiago Island to establish the parental population. F1 larvae were exposed to different concentrations of insecticides (Bacillus thuringiensis var israelensis (Bti), diflubenzuron and temephos) to estimate the lethal concentrations (LC90) and calculate the respective rate of resistance (RR90). Semi-field tests using temephos-ABATE(®) were performed to evaluate the persistence of the product. Bottle tests using female mosquitoes were carried out to determine the susceptibility to the adulticides malathion, cypermethrin and deltamethrin. Biochemical and molecular tests were performed to investigate the presence of metabolic resistance mechanisms, associated with the enzymes glutathione S-transferases (GSTs), esterases and mixed-function oxidases (MFO) and to detect mutations or alterations in the sodium channel and acetylcholinesterase genes. A. aegypti mosquitoes from Santiago exhibited resistance to deltamethrin, cypermethrin (mortality<80%) and temephos (RR90=4.4) but susceptibility to malathion (mortality≥98%), Bti and diflubenzuron. The low level of resistance to temephos did not affect the effectiveness of Abate(®). The enzymatic analysis conducted in 2012 revealed slight changes in the activities of GST (25%), MFO (18%), α-esterase (19%) and β-esterase (17%), but no significant changes in 2014. Target site resistance mutations were not detected. Our results suggest that the A. aegypti population from Santiago is resistant to two major

  6. Dietary control of late trypsin gene transcription in Aedes aegypti.

    Science.gov (United States)

    Noriega, F G; Barillas-Mury, C; Wells, M A

    1994-06-01

    In Aedes aegypti the levels of midgut trypsin activity after feeding are directly proportional to the protein concentration in the meal. The mechanisms of this up-regulatory event were investigated by analyzing the expression of the late trypsin gene under different dietary conditions. Transcription of the gene was dependent on both the quality and quantity of protein in the meal. As measured by Northern blot analysis, the levels of late trypsin gene expression increased up to 100-fold 24 h after feeding on gamma-globulin, hemoglobin or albumin (100 mg/ml). In contrast, gelatin, histone, amino acids, saline or agarose were very poor inducers of transcription. The rates of late trypsin transcription induced during the first 24 h were directly proportional to the concentration of protein in the meal. These data further support the suggestion that the primary mechanism that regulates the synthesis of trypsin in the mosquito midgut is transcriptional regulation of the gene. This regulatory mechanism enables the midgut to maintain the appropriate balance between protease synthesis and the protein content of the meal. PMID:7519098

  7. The lethal effects of Cyperus iria on Aedes aegypti.

    Science.gov (United States)

    Schwartz, A M; Paskewitz, S M; Orth, A P; Tesch, M J; Toong, Y C; Goodman, W G

    1998-03-01

    The sedge Cyperus iria, a common weed in rice, contains large amounts of the insect hormone (10R) juvenile hormone III (JH III). Given its widespread distribution in Asia and Africa, we examined the possibility that C. iria could be used as a safe, inexpensive, and readily available mosquito larvicide. Plants of varying ages were harvested and leaves tested for lethal effects on larvae of the yellow fever mosquito, Aedes aegypti. The median lethal doses (LD50s) for frozen leaves from 1- and 2-month-old plants were 267 and 427 mg/100 ml of water, respectively. Leaves from 1-month-old C. iria contained 193 micrograms JH III/g fresh weight, whereas leaves from 2-month-old plants contained 143 micrograms JH III/g fresh weight. Larval sensitivity to the plant differed with age; 4-day-old larvae displayed the greatest mortality followed in decreasing sensitivity by larvae 5, 6, 3, and 2 days old. Six Cyperus species (C. albostriatus, C. alternifolius, C. esculentus, C. iria, C. miliifolius, and C. papyrus) of similar developmental stage were assayed for JH III content. Only C. iria was found to contain significant levels of JH III. PMID:9599328

  8. Larvicidal activity of plant extracts on Aedes Aegypti L.

    Institute of Scientific and Technical Information of China (English)

    Anitha Rajasekaran; Geethapriya Duraikannan

    2012-01-01

    Objective: To evaluate the larvicidal activity of plant extracts on Aedes aegypti. Methods:Petroleum ether, Chloroform and aqueous extracts obtained from Acalypha indica, Aerva lanata,Boerhaavia diffusa, Commelina benghalensis, Gompherna sps, Datura stramonium, Euphorpia hirta, Cynodon dactylon, Lantana camara and Tridax procumbens were used for larvicidal activity at concentration of 1000μg/ml and the mortality rate was calculated after 24 and 48hrs . The LC50 for the extracts were also estimated after 24 hrs. Results: The petroleum ether extract ofLantana camara, Tridax procumbens and Datura stramonium showed 100% mortality after 48hrs of incubation. Tridax procumbens petroleum ether extract had the least LC50 of 219 μg/ml followed by Lantana and Datura with 251and 288 μg/ml respectively. A combination of petroleum ether extracts of Aerva lanata and Cynodon dactylon, Boerhaavia diffusa and Commelina benghalensis exhibited 100% mortality of larvae. Formulation-1 inhibited the metamorphosis of the larvae by retaining 60% in its larval stage. Petroleum ether extracts of Lantana, Tridax, Datura and a combination of extracts were effective larvicide. The formulations proved to be effective in inhibiting the metamorphosis. Alkaloids and flavonoids were present in datura petroleum ether extract . Conclusions: Either the crude extracts of Datura stramonium, Lantana camara and Tridax procumbens or its phytochemicals can be used as effective vector control agents individually or in combination.

  9. PEMETAAN, KARAKTERISTIK HABITAT DAN STATUS RESISTENSI Aedes aegypti DI KOTA BANJARMASIN KALIMANTAN SELATAN

    Directory of Open Access Journals (Sweden)

    Safitri -

    2013-12-01

    Full Text Available ABSTRACT. Control program of Aedes aegypti in Banjarmasin by using Malation has been done since almost 15 years ago. Related to this, a study about distribution and resistence of Ae.aegypti inBanjarmasin has been done. Ae.aegypti shown to be in almost all area in Banjarmasin, with water container in the bathroom and in the house are more liked. Susceptibility test showed thatthis mosquito was resistence to Malation 0,8%. Therefor, a policy to change this type of insecticide is needed.Key words : Ae.aegypti, resistence, dengue fever, Malation ABSTRAKProgram pengendalian nyamuk Aedes aegypti di Banjarmasin dengan menggunakan Malation telah dilakukan sejak hampir 15 tahun lalu. Terkait hal ini, sebuah studi tentang distribusi dan resistensi Ae. aegypti di Banjarmasin telah dilakukan. Ae. aegypti ditemukan di hampir semua wilayah di Banjarmasin dan lebih menyukai bak mandi dan penampungan air lainnya di dalam rumah. Uji Kerentanan menunjukkan bahwa nyamukini resisten terhadap Malation 0,8%. Maka, kebijakan untuk mengubah jenis insektisida yang digunakan sangat dibutuhkan Kata kunci: Ae. aegypti, resistensi, demam berdarah, Malation

  10. First Report of Aedes aegypti Transmission of Chikungunya Virus in the Americas.

    Science.gov (United States)

    Díaz-González, Esteban E; Kautz, Tiffany F; Dorantes-Delgado, Alicia; Malo-García, Iliana R; Laguna-Aguilar, Maricela; Langsjoen, Rose M; Chen, Rubing; Auguste, Dawn I; Sánchez-Casas, Rosa M; Danis-Lozano, Rogelio; Weaver, Scott C; Fernández-Salas, Ildefonso

    2015-12-01

    During a chikungunya fever outbreak in late 2014 in Chiapas, Mexico, entomovirological surveillance was performed to incriminate the vector(s). In neighborhoods, 75 households with suspected cases were sampled for mosquitoes, of which 80% (60) harbored Aedes aegypti and 2.7% (2) Aedes albopictus. A total of 1,170 Ae. aegypti and three Ae. albopictus was collected and 81 pools were generated. Although none of the Ae. albopictus pools were chikungunya virus (CHIKV)-positive, 18 Ae. aegypti pools (22.8%) contained CHIKV, yielding an infection rate of 32.3/1,000 mosquitoes. A lack of herd immunity in conjunction with high mosquito populations, poor vector control services in this region, and targeted collections in locations of human cases may explain the high infection rate in this vector. Consistent with predictions from experimental studies, Ae. aegypti appears to be the principal vector of CHIKV in southern Mexico, while the role of Ae. albopictus remains unknown. PMID:26416113

  11. Rhodopsin coexpression in UV photoreceptors of Aedes aegypti and Anopheles gambiae mosquitoes

    OpenAIRE

    Hu, Xiaobang; Leming, Matthew T; Whaley, Michelle A.; O'Tousa, Joseph E.

    2014-01-01

    Differential rhodopsin gene expression within specialized R7 photoreceptor cells divides the retinas of Aedes aegypti and Anopheles gambiae mosquitoes into distinct domains. The two species express the rhodopsin orthologs Aaop8 and Agop8, respectively, in a large subset of these R7 photoreceptors that function as ultraviolet receptors. We show here that a divergent subfamily of mosquito rhodopsins, Aaop10 and Agop10, is coexpressed in these R7 photoreceptors. The properties of the A. aegypti ...

  12. PENGARUH PENYULUHAN TERHADAP TINGKAT PENGET MASYARAKAT DAN KEPADATAN Aedes aegypti DI KECAMATAN BAYAH, PROVINSI BANTEN

    OpenAIRE

    Agnes Kurniawan; Rawina Winita; Saleha Sungkar

    2010-01-01

    The Effect of Health Education to Community Knowledge and Aedes aegypti Density in Bayah Subdistrict, Banten Province. Dengue Haemorrhagic Fever (DHF) is a public health problem in Bayah, Banten Province thus, control of mosquitoes breeding sites (CMBS) and health education is necessary. This study aimed to evaluate the effect of health education on people’s level of knowledge on CMBS and the density of Ae. aegypti. This study involved 106 villagers from Bayah in August (pretest) and October...

  13. Proteome of Aedes aegypti in response to infection and coinfection with microsporidian parasites

    OpenAIRE

    Duncan, Alison B; AGNEW, PHILIP; Noel, Valérie; Demettre, Edith; Seveno, Martial; Brizard, Jean-Paul; Michalakis, Yannis

    2012-01-01

    Hosts are frequently infected with more than one parasite or pathogen at any one time, but little is known as to how they respond to multiple immune challenges compared to those involving single infections. We investigated the proteome of Aedes aegypti larvae following infection with either Edhazardia aedis or Vavraia culicis, and coinfections involving both. They are both obligate intracellular parasites belonging to the phylum microsporidia and infect natural populations of Ae. aegypti. The...

  14. Larvicidal activity of Annona senegalensis and Boswellia dalzielii leaf fractions against Aedes aegypti (Diptera: Culicidae)

    OpenAIRE

    Younoussa Lame; Elias Nchiwan Nukenine; Danga Yinyang Simon Pierre; Charles Okechukwu Esimone

    2014-01-01

    The purpose of the present study was to evaluate the larvicidal activity of leaf fractions of Annona senegalensis and Boswellia dalzielii against fourth instar larvae of Aedes aegypti. Fourth instar larvae of Ae. aegypti were exposed for 24 hours to various concentrations (312.5-2500 mg/L) of methanolic crude extract and its fractions obtained with n-hexane, chloroform, ethyl-acetate and methanol solvents, following WHO method. The mortalities recorded were subjected to ANOVA test for mean co...

  15. Experimental Infection of Culex (Culex) quinquefasciatus and Aedes (Stegomyia) aegypti with Wuchereria bancrofti

    OpenAIRE

    Calheiros Cláudia ML; Fontes Gilberto; Williams Paul; Rocha Eliana MM

    1998-01-01

    A study was conducted to determine the susceptibility of local strains of Culex quinquefasciatus and Aedes aegypti to infection with the strain of Wuchereria bancrofti that occurs in Maceió, State of Alagoas, Brazil. Cx. quinquefasciatus blood fed simultaneously on the same microfilariae carrier ingested more blood and 2-3x more microfilariae than Ae. aegypti. Survival rates of both species of insects living for 21 days after blood feeding on microfilaraemic patients were not significantly di...

  16. Fitness cost in field and laboratory Aedes aegypti populations associated with resistance to the insecticide temephos

    OpenAIRE

    Diniz, Diego Felipe Araujo; de Melo-Santos, Maria Alice Varjal; Santos, Eloína Maria de Mendonça; Beserra, Eduardo Barbosa; Helvecio, Elisama; de Carvalho-Leandro, Danilo; dos Santos, Bianka Santana; de Menezes Lima, Vera Lúcia; Ayres, Constância Flávia Junqueira

    2015-01-01

    Background The continued use of chemical insecticides in the context of the National Program of Dengue Control in Brazil has generated a high selective pressure on the natural populations of Aedes aegypti, leading to their resistance to these compounds in the field. Fitness costs have been described as adaptive consequences of resistance. This study evaluated the biological and reproductive performance of A. aegypti strains and a field population resistant to temephos, the main larvicide used...

  17. Susceptibility of Aedes aegypti larvae to the insecticide temephos in the Federal District, Brazil

    OpenAIRE

    de Carvalho, M.D.S.; Caldas, E.D.; Dégallier, Nicolas; Vilarinhos, P.D.T.; de Souza, L.; Amelia, M.; Yoshizawa, C.; M. B. KNOX; Oliveira, C

    2004-01-01

    Objective: To study the susceptibility status of Aedes aegypti to the organophosphate insecticide temephos. Methods: Samples of Ae. aegypti larvae were obtained, using ovitraps, from eight cities of the Federal District, central Brazil, in 2000 and 2001. Larvae were submitted to the diagnostic dose of 0.012 mg/l temephos, as recommended by standard World Health Organization methodology. Field populations were tested in parallel with reference strains Rockefeller and DIVAL, from the Environmen...

  18. Spatial and temporal country-wide survey of temephos resistance in Brazilian populations of Aedes aegypti

    OpenAIRE

    Mateus Chediak; Fabiano G Pimenta Jr; Giovanini E Coelho; Ima A Braga; José Bento P Lima; Karina Ribeiro LJ Cavalcante; Lindemberg C. Sousa; Maria Alice V Melo-Santos; Maria de Lourdes da G Macoris; Ana Paula de Araújo; Ayres, Constância Flávia J; Maria Teresa M Andrighetti; Ricristhi Gonçalves de A Gomes; Campos, Kauara B; Raul Narciso C Guedes

    2016-01-01

    The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in...

  19. [Aedes (Stegomyia) aegypti L. and associated culicidae fauna in a urban area of southern Brazil].

    Science.gov (United States)

    Lopes, J; da Silva, M A; Borsato, A M; de Oliveira, V D; Oliveira, F J

    1993-10-01

    Some aspects of the ecology of eleven species of Culicidae that were found breeding in recipients in an urban area of Southern Brazil are presented. A great variety of recipients were listed as efficient breeding sites. Apparently Aedes aegypti has been recently introduced into the region and was limited to two areas of the city. Culex quinquefasciatus, Cx. coronator, Ae. aegypti, Ae. fluviatilis e Limatus durhamii were the predominant species.

  20. Molecular identification of Aedes aegypti mosquitoes from Pilani region of Rajasthan, India

    OpenAIRE

    Kuldeep Gupta; Rini Dhawan; Mithilesh Kajla; Sanjeev Kumar; B Jnanasiddhy; Singh, Naveen K.; Rajnikant Dixit; Ashish Bihani; Lalita Gupta

    2016-01-01

    Background & objectives: Aedes aegypti is the most important vector of dengue virus infection in humans worldwide. Accurate identification and colonization are the essential requirements to understand vector biology as well as its diseases transmission potential. In this study, we have used molecular approaches for the identification of Ae. aegypti mosquitoes that were collected from the Pilani region of Rajasthan, India Methods: Field collected mosquito larvae were colonized under laborat...

  1. Resistance Status to the Insecticides Temephos, Deltamethrin, and Diflubenzuron in Brazilian Aedes aegypti Populations

    OpenAIRE

    Bellinato, Diogo Fernandes; Viana-Medeiros, Priscila Fernandes; Araújo, Simone Costa; Martins, Ademir J; Lima, José Bento Pereira; Valle, Denise

    2016-01-01

    Insecticides are still largely applied in public health to control disease vectors. In Brazil, organophosphates (OP) and pyrethroids (PY) are used against Aedes aegypti for years. Since 2009 Insect Growth Regulators (IGR) are also employed in the control of larvae. We quantified resistance to temephos (OP), deltamethrin (PY), and diflubenzuron (IGR) of A. aegypti samples from 12 municipalities distributed throughout the country, collected between 2010 and 2012. High levels of resistance to ne...

  2. Effect of the chitin synthesis inhibitor triflumuron on the development, viability and reproduction of Aedes aegypti

    OpenAIRE

    Thiago Affonso Belinato; Ademir Jesus Martins; José Bento Pereira Lima; Tamara Nunes Lima-Camara; Alexandre Afrânio Peixoto; Denise Valle

    2009-01-01

    The control of Aedes aegypti is impaired due to the development of resistance to chemical insecticides. Insect Growth Regulators (IGR) exhibit distinct mechanisms of action and are considered potential vector control alternatives. Studies regarding the effects of sublethal IGR doses on the viability of resulting adults will contribute to eval-uating their impact in the field. We analyzed several aspects of Ae. aegypti adults surviving exposure to a partially lethal dose of triflumuron, a chit...

  3. Changing Domesticity of Aedes aegypti in Northern Peninsular Malaysia: Reproductive Consequences and Potential Epidemiological Implications

    OpenAIRE

    Saifur, Rahman G. M.; Dieng, Hamady; Hassan, Ahmad Abu; Salmah, Md Rawi Che; Satho, Tomomitsu; Miake, Fumio; Hamdan, Ahmad

    2012-01-01

    Background The domestic dengue vector Aedes aegypti mosquitoes breed in indoor containers. However, in northern peninsular Malaysia, they show equal preference for breeding in both indoor and outdoor habitats. To evaluate the epidemiological implications of this peridomestic adaptation, we examined whether Ae. aegypti exhibits decreased survival, gonotrophic activity, and fecundity due to lack of host availability and the changing breeding behavior. Methodology/Principal Findings This yearlon...

  4. Autophagy and viral diseases transmitted by Aedes aegypti and Aedes albopictus.

    Science.gov (United States)

    Carneiro, Leticia A M; Travassos, Leonardo H

    2016-03-01

    Despite a long battle that was started by Oswaldo Cruz more than a century ago, in 1903, Brazil still struggles to fight Aedes aegypti and Aedes albopictus, the mosquito vectors of dengue virus (DENV), Chikungynya virus (CHIKV) and Zika virus (ZIKV). Dengue fever has been a serious public health problem in Brazil for decades, with recurrent epidemic outbreaks occurring during summers. In 2015, until November, 1,534,932 possible cases were reported to the Ministry of Healthv. More recently, the less studied CHIKV and ZIKV have gained attention because of a dramatic increase in their incidence (around 400% for CHIKV) and the association of ZIKV infection with a 11-fold increase in the number of cases of microcephaly from 2014 to 2015 in northeast Brazil (1761 cases until December 2015). The symptoms of these three infections are very similar, which complicates the diagnosis. These include fever, headache, nausea, fatigue, and joint pain. In some cases, DENV infection develops into dengue hemorrhagic fever, a life threatening condition characterized by bleeding and decreases in platelet numbers in the blood. As for CHIKV, the most important complication is joint pain, which can last for months. PMID:26774331

  5. Diversity of containers and buildings infested with Aedes aegypti in Puerto Iguazú, Argentina Diversidad de recipientes y edificios infestados por Aedes aegypti en Puerto Iguazú, Argentina

    OpenAIRE

    Federico Costa; Gladys Fattore; Marcelo Abril

    2012-01-01

    Aedes aegypti is the main domestic vector of the dengue virus. Control measures to prevent dengue transmission focus on the treatment and elimination of this vector's oviposition sites. There is limited biological information on Ae. aegypti in Argentina. The aim of this study was to characterize Ae. aegypti oviposition sites in the city of Puerto Iguazú, Argentina. We surveyed an area covering nine neighborhoods in 2005. We identified 191 premises as positive for Ae. aegypti, giving a general...

  6. Pengaruh Modifikasi Ovitrap terhadap Kepadatan Nyamuk Aedes aegypti di Kelurahan Siopat Suhu Kota Pematang Siantar

    OpenAIRE

    Hasibuan, Lasni Fitryani

    2015-01-01

    The outbreak incident of dengue hemorrhagic fever (DHF) still frequently occurs in various areas in Indonesia. One of the ways of controlling theAedesAegypti mosquitos that is successful in decreasing vector density in several countries is the use of egg trap (ovitrap). Ovitrap is a device to attract mosquitos to lay their eggs in it. The purpose of this study was to test the influence of Ovitrap modification on the density of Aedes aegypti mosquitos by looking at the difference between Co...

  7. Estudio de la resistencia a insecticidas en Aedes aegypti (Diptera:Culicidae)

    OpenAIRE

    Rodríguez Coto, María Magdalena

    2008-01-01

    Aedes aegypti, Linnaeus, es el principal vector en la transmisión de la fiebre amarilla y dengue en las Américas. El control del vector es hasta la fecha la única opción para prevenir o reducir la transmisión de esta enfermedad, pero la resistencia a los insecticidas ha dificultado el control de esta especie. En este trabajo se evaluó la resistencia a insecticidas en ocho cepas de Aedes aegypti, colectados en Cuba (Ciudad Habana y Santiago de Cuba), y en otros países de la región de las Ameri...

  8. The RNA interference pathway affects midgut infection- and escape barriers for Sindbis virus in Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Olson Ken E

    2010-04-01

    Full Text Available Abstract Background The RNA interference (RNAi pathway acts as an innate antiviral immune response in Aedes aegypti, modulating arbovirus infection of mosquitoes. Sindbis virus (SINV; family: Togaviridae, genus: Alphavirus is an arbovirus that infects Ae. aegypti in the laboratory. SINV strain TR339 encounters a midgut escape barrier (MEB during infection of Ae. aegypti. The nature of this barrier is not well understood. To investigate the role of the midgut as the central organ determining vector competence for arboviruses, we generated transgenic mosquitoes in which the RNAi pathway was impaired in midgut tissue of bloodfed females. We used these mosquitoes to reveal effects of RNAi impairment in the midgut on SINV replication, midgut infection and dissemination efficiencies, and mosquito longevity. Results As a novel tool for studying arbovirus-mosquito interactions, we engineered a transgenic mosquito line with an impaired RNAi pathway in the midgut of bloodfed females by silencing expression of the Aa-dcr2 gene. In midgut tissue of the transgenic Carb/dcr16 line, Aa-dcr2 expression was reduced ~50% between 1-7 days post-bloodmeal (pbm when compared to the recipient mosquito strain. After infection with SINV-TR339EGFP, Aa-dcr2 expression levels were enhanced in both mosquito strains. In the RNAi pathway impaired mosquito strain SINV titers and midgut infection rates were significantly higher at 7 days pbm. There was also a strong tendency for increased virus dissemination rates among the transgenic mosquitoes. Between 7-14 days pbm, SINV was diminished in midgut tissue of the transgenic mosquitoes. Transgenic impairment of the RNAi pathway and/or SINV infection did not affect longevity of the mosquitoes. Conclusions We showed that RNAi impaired transgenic mosquitoes are a useful tool for studying arbovirus-mosquito interactions at the molecular level. Following ingestion by Ae. aegypti, the recombinant SINV-TR339EGFP was confronted with both

  9. Effect of common salt on laboratory reared immature stages ofAedes aegypti (L)

    Institute of Scientific and Technical Information of China (English)

    Mukhopadhyay AK; Tamizharasu W; Satya Babu P; Chandra G; Hati AK

    2010-01-01

    Objective:To observe the effect of common salt (NaCl) on immature stages of laboratory reared Aedes aegypti (L).Methods:A laboratory colony ofAedes aegypti mosquitoes of Rajahmundry strain was established in the laboratory of National Institute for Communicable Disease(NICD), Rajahmundry unit at (26±2) ℃ with relative humidity of (70±10)%. 1.00%, 1.25% and 1.50% solutions of common salt (NaCl) were selected to observe the susceptibility status of immature stages ofAedes aegypti in laboratory.Results: Fifty percent larvae ofAedes aegyptidied within 19, 31 and 48 hours when exposed to 1.50%, 1.25% and 1.00% common salt solution, respectively. Ninety percent of the larvae died within 29, 57 and 108 hours when exposed to the same salt solutions, respectively. Very high pupal mortality was observed varying from 81.8% to 40.0%. Formation of pupae was found inversely proportional in the presence of concentration of common salt in breeding water.Conclusions: With easy availability, less toxicity and long lasting nature, common salt may be applied in unused containers, especially in junkyards where surveillance mechanism is poor along with other conventional vector control methods in order to control breeding ofAedes aegypti, the vector of dengue/ dengue hemorrhagic fever and chikungunya.

  10. Identification of carboxylesterase genes implicated in temephos resistance in the dengue vector Aedes aegypti.

    OpenAIRE

    Rodolphe Poupardin; Wannaporn Srisukontarat; Cristina Yunta; Hilary Ranson

    2014-01-01

    BACKGROUND: Thailand is currently experiencing one of its worst dengue outbreaks in decades. As in most countries where this disease is endemic, dengue control in Thailand is largely reliant on the use of insecticides targeting both immature and adult stages of the Aedes mosquito, with the organophosphate insecticide, temephos, being the insecticide of choice for attacking the mosquito larvae. Resistance to temephos was first detected in Aedes aegypti larvae in Thailand approximately 25 years...

  11. The Effectiveness of Organotin (IV Benzylisopropyldithiocarbamate Compounds as Insecticide Against Aedes Aegypti Linn (Diptera: Culicidae in Laboratory

    Directory of Open Access Journals (Sweden)

    Normah Awang

    2012-01-01

    Full Text Available Problem statement: The widespread use of insecticides had resulted in insecticide resistance of vectors of dengue as well as polluting the environment. Organotin (IV compounds had the potential to be developed as the insecticides to overcome the existing problem. Approach: The aim of this study was to examine the insecticidal effects which were larvicidal and adulticidal effects of organotin (IV benzylisopropyldithiocarbamate compounds against Aedes Aegypti Linn. In laboratory larvicidal bioassay test of a series of three organotin (IV benzylisopropyldithiocarbamate compounds on third instar larvae of Aedes Aegypti had been carried out. Results: The study was found that compound B showed the best larvicidal effect with the LC50 and LC90 values of 0.004 ppm and 0.007 ppm, respectively. Compound C was also displayed good larvicidal effect with the LC50 and LC90 values of 0.029 ppm and 0.108 ppm, respectively. While, compound A was shown the least larvicidal effect with the LC50 and LC90 values of 0.404 ppm and 0.749 ppm, respectively. Further testing was conducted on compound B on adults of Aedes ageypti female to investigate its adulticidal property. The result showed that compound B displayed good adulticidal activity with LC50 dan LC90 of 4.277 ppm and 27.653 ppm, respectively. Conclusion: Compound B is the most effective compound among three organotin (IV benzylisopropyldithiocarbamate compounds tested against the dengue vector Aedes Aegypti and has potential to be explored as an insecticide to control the spread of dengue fever.

  12. Aedes aegypti larvicide from the ethanolic extract of Piper nigrum black peppercorns.

    Science.gov (United States)

    Santiago, Viviene S; Alvero, Rita Grace; Villaseñor, Irene M

    2015-01-01

    Due to unavailability of a vaccine and a specific cure to dengue, the focus nowadays is to develop an effective vector control method against the female Aedes aegypti mosquito. This study aims to determine the larvicidal fractions from Piper nigrum ethanolic extracts (PnPcmE) and to elucidate the identity of the bioactive compounds that comprise these larvicidal fractions. Larvicidal assay was performed by subjecting 3rd to 4th A. aegypti instar larvae to PnPcmE of P. nigrum. The PnPcmE exhibited potential larvicidal activity having an LC50 of 7.1246 ± 0.1304 ppm (mean ± Std error). Normal phase vacuum liquid chromatography of the PnPcmE was employed which resulted in five fractions, two of which showed larvicidal activity. The most active of the PnPcmE fractions is PnPcmE-1A, with an LC50 and LC90 of 1.7101 ± 0.0491 ppm and 3.7078 ppm, respectively. Subsequent purification of PnPcmE-1A allowed the identification of the larvicidal compound as oleic acid.

  13. Changes in host-seeking behavior of Puerto Rican Aedes aegypti after colonization.

    Science.gov (United States)

    Clark, Gary G; Bernier, Ulrich R; Allan, Sandra A; Kline, Daniel L; Golden, Frances V

    2011-05-01

    The effects of colonization on host-seeking behavior of mosquitoes was examined by comparing attraction responses of newly colonized Aedes aegypti (L.) from field-collected eggs in Puerto Rico to that of the Gainesville (Florida) strain, originally from Orlando (Florida) and in colony since 1952. Females from the Orlando and the F0 through F10 generations of the Puerto Rico strain were evaluated using attractant odors in a triple-cage dual-port olfactometer. Two attractant sources were used: odors from the hand of a volunteer and a standard blend of L-lactic acid, acetone, and dimethyl disulfide. Convergence of the percentage of attraction responses occurred around the F4-F6 generations of the Puerto Rico strain. Both the Orlando and Puerto Rico strains exhibited similar responses for tests with the remaining F7-F10 generations. A temporal effect on mosquito responses was observed for both strains regardless of the attractant blend used in tests. This study indicates that Ae. aegypti host-seeking behavior changes significantly over the first four to six generations after introduction into the laboratory, whereas the field-collected strain increases in attraction response until it stabilizes at a new level. PMID:21661313

  14. Dynamics of midgut microflora and dengue virus impact on life history traits in Aedes aegypti.

    Science.gov (United States)

    Hill, Casey L; Sharma, Avinash; Shouche, Yogesh; Severson, David W

    2014-12-01

    Significant morbidity and potential mortality following dengue virus infection is a re-emerging global health problem. Due to the limited effectiveness of current disease control methods, mosquito biologists have been searching for new methods of controlling dengue transmission. While much effort has concentrated on determining genetic aspects to vector competence, paratransgenetic approaches could also uncover novel vector control strategies. The interactions of mosquito midgut microflora and pathogens may play significant roles in vector biology. However, little work has been done to see how the microbiome influences the host's fitness and ultimately vector competence. Here we investigated the effects of the midgut microbial environment and dengue infection on several fitness characteristics among three strains of the primary dengue virus vector mosquito Aedes aegypti. This included comparisons of dengue infection rates of females with and without their normal midgut flora. According to our findings, few effects on fitness characteristics were evident following microbial clearance or with dengue virus infection. Adult survivorship significantly varied due to strain and in one strain varied due to antibiotic treatment. Fecundity varied in one strain due to microbial clearance by antibiotics but no variation was observed in fertility due to either treatment. We show here that fitness characteristics of Ae. aegypti vary largely between strains, including varying response to microflora presence or absence, but did not vary in response to dengue virus infection. PMID:25193134

  15. Rhythms and synchronization patterns in gene expression in the Aedes aegypti mosquito

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    Carlson Jonathan O

    2011-03-01

    Full Text Available Abstract Background Aedes aegypti is arguably the most studied of all mosquito species in the laboratory and is the primary vector of both Dengue and Yellow Fever flaviviruses in the field. A large number of transcriptional studies have been made in the species and these usually report transcript quantities observed at a certain age or stage of development. However, circadian oscillation is an important characteristic of gene expression in many animals and plants, modulating both their physiology and behavior. Circadian gene expression in mosquito species has been previously reported but for only a few genes directly involved in the function of the molecular clock. Results Herein we analyze the transcription profiles of 21,494 messenger RNAs using an Ae. aegypti Agilent® microarray. Transcripts were quantified in adult female heads at 24 hours and then again at 72 hours and eight subsequent time points spaced four hours apart. We document circadian rhythms in multiple molecular pathways essential for growth, development, immune response, detoxification/pesticide resistance. Circadian rhythms were also noted in ribosomal protein genes used for normalization in reverse transcribed PCR (RT-PCR to determine transcript abundance. We report pervasive oscillations and intricate synchronization patterns relevant to all known biological pathways. Conclusion These results argue strongly that transcriptional analyses either need to be made over time periods rather than confining analyses to a single time point or development stage or exceptional care needs to be made to synchronize all mosquitoes to be analyzed and compared among treatment groups.

  16. Impact of elevated CO2 background levels on the host-seeking behaviour of Aedes aegypti.

    Science.gov (United States)

    Majeed, Shahid; Hill, Sharon Rose; Ignell, Rickard

    2014-02-15

    Mosquitoes rely on carbon dioxide (CO2) to detect and orient towards their blood hosts. However, the variable and rapid fluctuations of atmospheric CO2 concentrations may have an impact on the host-seeking behaviour of mosquitoes. In this study, we analysed the effect of transient elevated background levels of CO2 on the host-seeking behaviour and the physiological characteristics of the CO2-sensitive olfactory receptor neurones (ORNs) in female yellow fever mosquitoes, Aedes aegypti. We show that the take-off and source contact behaviour of A. aegypti is impeded at elevated background levels of CO2 as a result of masking of the stimulus signal. The mechanism underlying this masking during take-off behaviour is one of sensory constraint. We show that the net response of the CO2-ORNs regulates this CO2-related behaviour. Since these neurones themselves are not habituated or fatigued by the transient elevation of background CO2, we propose that habituation of second-order neurones in response to the elevated CO2-ORN activity could be one mechanism by which the net response is transduced by the olfactory system. The findings from this study may help to predict future shifts in mosquito-host interactions and consequently to predict vectorial capacity in the light of climate change.

  17. Aedes aegypti larvicide from the ethanolic extract of Piper nigrum black peppercorns.

    Science.gov (United States)

    Santiago, Viviene S; Alvero, Rita Grace; Villaseñor, Irene M

    2015-01-01

    Due to unavailability of a vaccine and a specific cure to dengue, the focus nowadays is to develop an effective vector control method against the female Aedes aegypti mosquito. This study aims to determine the larvicidal fractions from Piper nigrum ethanolic extracts (PnPcmE) and to elucidate the identity of the bioactive compounds that comprise these larvicidal fractions. Larvicidal assay was performed by subjecting 3rd to 4th A. aegypti instar larvae to PnPcmE of P. nigrum. The PnPcmE exhibited potential larvicidal activity having an LC50 of 7.1246 ± 0.1304 ppm (mean ± Std error). Normal phase vacuum liquid chromatography of the PnPcmE was employed which resulted in five fractions, two of which showed larvicidal activity. The most active of the PnPcmE fractions is PnPcmE-1A, with an LC50 and LC90 of 1.7101 ± 0.0491 ppm and 3.7078 ppm, respectively. Subsequent purification of PnPcmE-1A allowed the identification of the larvicidal compound as oleic acid. PMID:25118563

  18. PEMETAAN, KARAKTERISTIK HABITAT DAN STATUS RESISTENSI Aedes aegypti DI KOTA BANJARMASIN KALIMANTAN SELATAN

    OpenAIRE

    Safitri -

    2013-01-01

    ABSTRACT. Control program of Aedes aegypti in Banjarmasin by using Malation has been done since almost 15 years ago. Related to this, a study about distribution and resistence of Ae.aegypti inBanjarmasin has been done. Ae.aegypti shown to be in almost all area in Banjarmasin, with water container in the bathroom and in the house are more liked. Susceptibility test showed thatthis mosquito was resistence to Malation 0,8%. Therefor, a policy to change this type of insecticide is needed.Key word...

  19. Amostragem por larva-única na vigilância de Aedes aegypti Single-larva sampling for Aedes aegypti surveillance

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    José Eduardo Bracco

    1995-04-01

    Full Text Available Com a finalidade de testar a metodologia de amostragem por larva-única na vigilância entomológica do Aedes aegypti, foram pesquisados domicílios do Município de Araraquara, SP (Brasil. Nos criadouros que continham larvas de Aedes uma delas foi coletada. Como controle, após a coleta da larva-única, todas as larvas foram coletadas para identificação posterior. Esse processo foi repetido no laboratório. Dos 447 domicílios visitados, apenas 12 foram considerados positivos e 20 criadouros foram identificados; destes, 13 continham larvas de Aedes; 5, larvas de Aedes e Culex e 2, larvas de Culex. Os resultados mostram o reconhecimento correto, no campo, de todos os criadouros, evidenciando que o método poderia ser utilizado na vigilância entomológica de municípios sem infestação domiciliar ou infestados apenas com uma única espécie de Aedes.Buildings in Araraquara city, Southeastern Brazil, were searched during a year for the presence of Aedes larvae using single larva sampling in order to check the single-larva methodology. In those breeding places in wich Aedes larvae were found, one of them was collected. As a control, after the single larva had been collected, all the larvae from the breeding place were collected for later identification. This process was repeated in the laboratory. Of the 447 domiciles searched, 12 were considered positive and 20 breeding places were found. Of the breeding places, 13 contained Aedes larvae, 5 both Aedes and Culex larvae and 2 Culex larvae only. The results show that all the breeding places in the field were properly recognited showing the method may be used for Aedes surveillance in cities infested with one species only or without any domiciliary infestation.

  20. Occurrence of Toxorhynchites guadeloupensis (Dyar and Knab) in oviposition trap of Aedes aegypti (L.) (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Honorio, Nildimar A. [Instituto Oswaldo Cruz (FIOCRUZ), Rio de Janeiro, RJ (Brazil). Dept. de Entomologia. Lab. de Transmissores de Hematozoarios; Barros, Fabio S.M. de [Universidade Federal de Roraima (UFRR), Boa Vista, RR (Brazil). Centro de Ciencias Biologicas e da Saude. Nucleo Avancado de Vetores; Tsouris, Pantelis; Rosa-Freitas, Maria G. [Freitas and Tsouris Consultants, Spata-Attikis (Greece)]. E-mail: maria@freitas-tsouris.com

    2007-09-15

    Toxorhynchites guadeloupensis (Dyar and Knab), a poorly known mosquito species, was observed preying upon Aedes aegypti (L.) larvae, in an oviposition trap placed for routine dengue entomological surveillance, during 2003-2004 in the urban area of Boa Vista, Roraima, Brazil. This is the first report for Tx. guadeloupensis using Ae. aegypti oviposition traps as breeding places. This finding may have important consequences in the epidemiology and local dengue control since Ae. aegypti density is a basic variable in dengue prediction. Whether predation of Ae aegypti by Tx. guadeloupensis in the Amazon is of significance, is a question to be examined. Also, larval predation may be a cause for underestimation of the actual Ae aegypti numbers. Together these hypotheses need to be better investigated as they are directly related to dengue epidemiology, to the success of any outbreak prediction and surveillance program. (author)

  1. Occurrence of Toxorhynchites guadeloupensis (Dyar and Knab) in oviposition trap of Aedes aegypti (L.) (Diptera: Culicidae)

    International Nuclear Information System (INIS)

    Toxorhynchites guadeloupensis (Dyar and Knab), a poorly known mosquito species, was observed preying upon Aedes aegypti (L.) larvae, in an oviposition trap placed for routine dengue entomological surveillance, during 2003-2004 in the urban area of Boa Vista, Roraima, Brazil. This is the first report for Tx. guadeloupensis using Ae. aegypti oviposition traps as breeding places. This finding may have important consequences in the epidemiology and local dengue control since Ae. aegypti density is a basic variable in dengue prediction. Whether predation of Ae aegypti by Tx. guadeloupensis in the Amazon is of significance, is a question to be examined. Also, larval predation may be a cause for underestimation of the actual Ae aegypti numbers. Together these hypotheses need to be better investigated as they are directly related to dengue epidemiology, to the success of any outbreak prediction and surveillance program. (author)

  2. The wMel strain of Wolbachia Reduces Transmission of Zika virus by Aedes aegypti

    Science.gov (United States)

    Aliota, Matthew T.; Peinado, Stephen A.; Velez, Ivan Dario; Osorio, Jorge E.

    2016-01-01

    Zika virus (ZIKV) is causing an explosive outbreak of febrile disease in the Americas. There are no effective antiviral therapies or licensed vaccines for this virus, and mosquito control strategies have not been adequate to contain the virus. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against other arboviruses. At present, it is unknown whether or not ZIKV can infect, disseminate, and be transmitted by Wolbachia-infected Ae. aegypti. Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for ZIKV. These results support the use of Wolbachia biocontrol as a multivalent strategy against Ae. aegypti-transmitted viruses. PMID:27364935

  3. Potency of Gynura pseudochina (L. DC. Extract as Aedes aegypti (Linn. Larvacide

    Directory of Open Access Journals (Sweden)

    Rina Marina

    2012-06-01

    Full Text Available Aedes aegypti is the main vector of dengue virus transmission for dengue fever. The effective method to reduce dengue cases is to used a biological insecticides such as Gynura pseudochina at larval stage of A.aegypti. The research was performed to find out the Gy. pseudochina leafs extracts potential as an Ae. aegypti larvacide. This experimental research conducted with completely randomized design that used seven different concentrations (0%, 5%, 6%, 7%, 8%, 9%, 10%. As the result, there were mean differences in the Ae. aegypti larvae mortality at each concentration of Gy. pseudochina group, except for the concentration 5% to 6% and 9% to 10%. After 24 hours treatment, LC50 was gained at 6.271% extract concentration with a lower limit at 5.322% and upper limit at 7.005%. This result shows, Gy. pseudochina leafs extracts has proved to be a potential Ae. aegypti larvacide.

  4. The wMel strain of Wolbachia Reduces Transmission of Zika virus by Aedes aegypti.

    Science.gov (United States)

    Aliota, Matthew T; Peinado, Stephen A; Velez, Ivan Dario; Osorio, Jorge E

    2016-01-01

    Zika virus (ZIKV) is causing an explosive outbreak of febrile disease in the Americas. There are no effective antiviral therapies or licensed vaccines for this virus, and mosquito control strategies have not been adequate to contain the virus. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against other arboviruses. At present, it is unknown whether or not ZIKV can infect, disseminate, and be transmitted by Wolbachia-infected Ae. aegypti. Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for ZIKV. These results support the use of Wolbachia biocontrol as a multivalent strategy against Ae. aegypti-transmitted viruses. PMID:27364935

  5. Gustatory receptor neuron responds to DEET and other insect repellents in the yellow-fever mosquito, Aedes aegypti

    Science.gov (United States)

    Sanford, Jillian L.; Shields, Vonnie D. C.; Dickens, Joseph C.

    2013-03-01

    Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow-fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as N, N-diethyl-3-methylbenzamide and other insect repellents. Two other neurons with differing spikes responded to salt (NaCl) and sucrose. This is the first report of a gustatory receptor neuron specific for insect repellents in mosquitoes and may provide a tool for screening chemicals to discover novel or improved feeding deterrents and repellents for use in the management of arthropod disease vectors.

  6. Comparative efficacy of existing surveillance tools for Aedes aegypti in Western Kenya.

    Science.gov (United States)

    Yalwala, Sancto; Clark, Jeffrey; Oullo, David; Ngonga, Daniel; Abuom, David; Wanja, Elizabeth; Bast, Joshua

    2015-12-01

    All traditional surveillance techniques for Aedes aegypti have been developed for the cosmopolitan domestic subspecies Ae. aegypti aegypti, and not the sylvatic subspecies, Ae. aegypti formosus. The predominant form in Western Kenya is Ae. aegypti formosus that is rarely associated with human habitations but is linked to transmission of sylvatic dengue virus strains. We compared five surveillance methods for their effectiveness in sampling Ae. aegypti formosus with the goal of determining a sustainable surveillance strategy in Kenya. The methods included larval and pupal surveys, oviposition trapping, BG-Sentinel trapping, resting boxes, and backpack aspirations. Larval and pupal surveys collected the highest number of Ae. aegypti formosus (51.3%), followed by oviposition traps (45.7%), BG-Sentinel traps (3.0%), and zero collected with either backpack aspiration or resting box collections. No Ae. aegypti formosus larvae or pupae were found indoors. The results indicate that oviposition traps and outdoor larval and pupal surveys were better surveillance methods for Ae. aegypti formosus in Western Kenya. PMID:26611965

  7. High quality RNA isolation from Aedes aegypti midguts using laser microdissection microscopy

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    Gobert Geoffrey N

    2011-05-01

    Full Text Available Abstract Background Laser microdissection microscopy (LMM has potential as a research tool because it allows precise excision of target tissues or cells from a complex biological specimen, and facilitates tissue-specific sample preparation. However, this method has not been used in mosquito vectors to date. To this end, we have developed an LMM method to isolate midgut RNA using Aedes aegypti. Results Total RNA was isolated from Ae. aegypti midguts that were either fresh-frozen or fixed with histological fixatives. Generally, fresh-frozen tissue sections are a common source of quality LMM-derived RNA; however, our aim was to develop an LMM protocol that could inactivate pathogenic viruses by fixation, while simultaneously preserving RNA from arbovirus-infected mosquitoes. Three groups (10 - 15 mosquitoes per group of female Ae. aegypti at 24 or 48-hours post-blood meal were intrathoracically injected with one of seven common fixatives (Bouin's, Carnoy's, Formoy's, Cal-Rite, 4% formalin, 10% neutral buffered formalin, or zinc formalin to evaluate their effect on RNA quality. Total RNA was isolated from the fixed abdomens using a Trizol® method. The results indicated that RNA from Carnoy's and Bouin's fixative samples was comparable to that of fresh frozen midguts (control in duplicate experiments. When Carnoy's and Bouin's were used to fix the midguts for the LMM procedure, however, Carnoy's-fixed RNA clearly showed much less degradation than Bouin's-fixed RNA. In addition, a sample of 5 randomly chosen transcripts were amplified more efficiently using the Carnoy's treated LMM RNA than Bouin's-fixed RNA in quantitative real-time PCR (qRT-PCR assays, suggesting there were more intact target mRNAs in the Carnoy's fixed RNA. The yields of total RNA ranged from 0.3 to 19.0 ng per ~3.0 × 106 μm2 in the LMM procedure. Conclusions Carnoy's fixative was found to be highly compatible with LMM, producing high quality RNA from Ae. aegypti midguts while

  8. Effects of Metarhizium anisopliae conidia mixed with soil against the eggs of Aedes aegypti.

    Science.gov (United States)

    Leles, Renan Nunes; D'Alessandro, Walmirton Bezerra; Luz, Christian

    2012-04-01

    The effectiveness of Metarhizium anisopliae IP 46 conidia mixed with soil was tested against Aedes aegypti eggs. Mycelium and new conidia developed first on eggs between 4.8 and 15 days respectively after incubation of fungus-treated soils at 3.3 × 10(3) up to 3.3 × 10(5) conidia/g soil at 25°C and relative humidities close to saturation. After 15-day incubation, 53.3% of the eggs exposed to soil with 3.3 × 10(5) conidia/g showed external development of mycelium and conidia. Fungus-inoculated soils (but not untreated controls) showed some mycelial growth and sporulation apart from the eggs. Some eggs on treated soils hatched; those larvae died and eventually showed fungal development on their bodies. The cumulative relative eclosion of larvae after submersion of treated eggs in water decreased from 52.2% at 3.3 × 10(3) conidia/g to 25.3% at 3.3 × 10(5) conidia/g. These findings clearly showed that A. aegypti eggs can be infected by M. anisopliae when deposited on fungus-contaminated soil. The effectiveness of M. anisopliae against gravid females, larvae, and also eggs of A. aegypti underscored the possible usefulness of this fungus as a mycoinsecticide, whether naturally occurring or artificially applied, in the breeding sites of this mosquito. PMID:21984368

  9. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California

    Science.gov (United States)

    Cornel, Anthony J.; Holeman, Jodi; Nieman, Catelyn C.; Lee, Yoosook; Smith, Charles; Amorino, Mark; Brisco, Katherine K.; Barrera, Roberto; Lanzaro, Gregory C.; Mulligan III, F. Stephen

    2016-01-01

    The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS) traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B), when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV) trials using a new formulation of deltamethrin (DeltaGard®) demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath) after a single truck mounted aerial ULV application in residential areas. PMID:27158450

  10. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae) population in California.

    Science.gov (United States)

    Cornel, Anthony J; Holeman, Jodi; Nieman, Catelyn C; Lee, Yoosook; Smith, Charles; Amorino, Mark; Brisco, Katherine K; Barrera, Roberto; Lanzaro, Gregory C; Mulligan Iii, F Stephen

    2016-01-01

    The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS) traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B), when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV) trials using a new formulation of deltamethrin (DeltaGard®) demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath) after a single truck mounted aerial ULV application in residential areas.

  11. Evidence of experimental vertical transmission of emerging novel ECSA genotype of Chikungunya Virus in Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Ankita Agarwal

    Full Text Available BACKGROUND: Chikungunya virus (CHIKV has emerged as one of the most important arboviruses of public health significance in the past decade. The virus is mainly maintained through human-mosquito-human cycle. Other routes of transmission and the mechanism of maintenance of the virus in nature are not clearly known. Vertical transmission may be a mechanism of sustaining the virus during inter-epidemic periods. Laboratory experiments were conducted to determine whether Aedes aegypti, a principal vector, is capable of vertically transmitting CHIKV or not. METHODOLOGY/PRINCIPAL FINDINGS: Female Ae. aegypti were orally infected with a novel ECSA genotype of CHIKV in the 2nd gonotrophic cycle. On day 10 post infection, a non-infectious blood meal was provided to obtain another cycle of eggs. Larvae and adults developed from the eggs obtained following both infectious and non-infectious blood meal were tested for the presence of CHIKV specific RNA through real time RT-PCR. The results revealed that the larvae and adults developed from eggs derived from the infectious blood meal (2nd gonotrophic cycle were negative for CHIKV RNA. However, the larvae and adults developed after subsequent non-infectious blood meal (3rd gonotrophic cycle were positive with minimum filial infection rates of 28.2 (1∶35.5 and 20.2 (1∶49.5 respectively. CONCLUSION/SIGNIFICANCE: This study is the first to confirm experimental vertical transmission of emerging novel ECSA genotype of CHIKV in Ae. aegypti from India, indicating the possibilities of occurrence of this phenomenon in nature. This evidence may have important consequence for survival of CHIKV during adverse climatic conditions and inter-epidemic periods.

  12. Mechanical transmission of Bacillus anthracis by stable flies (Stomoxys calcitrans) and mosquitoes (Aedes aegypti and Aedes taeniorhynchus).

    OpenAIRE

    Turell, M J; Knudson, G B

    1987-01-01

    We evaluated the potential of stable flies, Stomoxys calcitrans, and two species of mosquitoes, Aedes aegypti and Aedes taeniorhynchus, to transmit Bacillus anthracis Vollum 1B mechanically. After probing on Hartley guinea pigs with a bacteremia of ca. 10(8.6) CFU of B. anthracis per ml of blood, individual or pools of two to four stable flies or mosquitoes were allowed to continue feeding on either uninfected guinea pigs or A/J mice. All three insect species transmitted lethal anthrax infect...

  13. Parity and longevity of Aedes aegypti according to temperatures in controlled conditions and consequences on dengue transmission risks.

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    Daniella Goindin

    Full Text Available In Guadeloupe, Aedes aegypti mosquitoes are the only vectors of dengue and chikungunya viruses. For both diseases, vector control is the only tool for preventing epidemics since no vaccine or specific treatment is available. However, to efficiently implement control of mosquitoes vectors, a reliable estimation of the transmission risks is necessary. To become infective an Ae. aegypti female must ingest the virus during a blood meal and will not be able to transmit the virus during another blood-meal until the extrinsic incubation period is completed. Consequently the aged females will carry more infectious risks. The objectives of the present study were to estimate under controlled conditions the expectation of infective life for females and thus the transmission risks in relation with their reproductive cycle and parity status.Larvae of Ae. aegypti were collected in central Guadeloupe and breed under laboratory conditions until adult emergence. The experiments were performed at constant temperatures (± 1.5°C of 24°C, 27°C and 30°C on adults females from first generation (F1. Females were kept and fed individually and records of blood-feeding, egg-laying and survival were done daily. Some females were dissected at different physiological stages to observe the ovaries development. The data were analyzed to follow the evolution of parity rates, the number of gonotrophic cycles, the fecundity and to study the mean expectation of life and the mean expectation of infective life for Ae. aegypti females according to temperatures. The expectation of life varies with the parity rates and according to the temperatures, with durations from about 10 days at low parity rates at the higher temperature to an optimal duration of about 35 days when 70% of females are parous at 27°C. Infective life expectancy was found highly variable in the lower parous rates and again the optimal durations were found when more than 50% of females are parous for the mean

  14. Electroantennogram, flight orientation and oviposition responses of Anopheles stephensi and Aedes aegypti to a fatty acid ester-propyl octadecanoate.

    Science.gov (United States)

    Seenivasagan, Thangaraj; Sharma, Kavita R; Prakash, Shri

    2012-10-01

    Studies were carried out to evaluate the role of a C(21)-fatty acid ester; propyl octadecanoate (PO) for olfaction-mediated behavioral responses of urban malaria vector, Anopheles stephensi and dengue vector, Aedes aegypti mosquitoes using electroantennogram (EAG), flight orientation and oviposition experiments. Dose dependent electrophysiological responses were recorded for PO from the antenna of both mosquito species in which 10(-5) g elicited significant EAG response. An. stephensi exhibited 2.4, 4.2 and 5.5 fold increased EAG response compared to control, while Ae. aegypti showed 1.9, 4.6 and 5.8 fold EAG responses respectively at 10(-7) g, 10(-6) g and 10(-5) g doses. In the Y-tube olfactometer, 77-80% gravid females of An. stephensi, and 64-77% of Ae. aegypti were caught in the chambers releasing 10(-6) g and 10(-5) g plume of PO. The synthetic fatty acid ester loaded onto an effervescent tablet at 0.1 mg/L, 1 mg/L and 10 mg/L elicited increased ovipositional responses from gravid mosquitoes compared to control. The oviposition activity indices (OAI) of An. stephensi females were +0.40, +0.51 and +0.58, whereas the OAI for Ae. aegypti females were +0.05, +0.36 and +0.57 respectively in 0.1, 1, 10 mg/L of PO; indicated concentration dependent increased egg deposition. Similarly, in the residual activity studies, oviposition substrates treated with PO on effervescent tablet at 1mg/L and 10mg/L received significantly increased egg deposition by gravid females of both mosquito species for up to 1 week compared to control substrates. PO can potentially be used in ovitraps to monitor An. stephensi and Ae. aegypti populations in the vector surveillance programs.

  15. Insecticide susceptible/resistance status in Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera : Culicidae) in Thailand during 2003-2005

    OpenAIRE

    Jirakanjanakit, N.; Rongnoparut, P.; Saengtharatip, S.; T Chareonviriyaphap; Duchn, S.; Bellec, Christian; Yoksan, S

    2007-01-01

    Susceptibility baselines and diagnostic doses of the technical grade insecticides deltamethrin, permethrin, fenitrothion, and propoxur were established based on Aedes aegypti (L.), Bora (French Polynesia), a reference susceptible strain. Field-collected Aedes mosquitoes from each part of Thailand were subjected to bioassay for their susceptibility to the diagnostic doses of each insecticide. Almost all Ae. aegypti collected were incipient resistant or resistant to deltamethrin and permethrin,...

  16. Different repellents for Aedes aegypti against blood-feeding and oviposition.

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    Ali Afify

    Full Text Available Methyl N,N-dimethyl anthranilate (MDA, ethyl anthranilate (EA and butyl anthranilate (BA were previously shown to repel Aedes aegypti mosquitoes from landing on human skin. However, the effect of these compounds on the orientation of flying mosquitoes in a choice situation and their effect on mosquito oviposition are not yet known. Here, we used a modified Y-tube olfactometer to test the effect of these compounds on the orientation of Aedes aegypti flying towards skin odor (human fingers, and we tested their effect on Aedes aegypti oviposition choice in a cage assay. In both behavioral situations we compared the effect to the well-documented repellent N,N-diethyl-meta-toluamide (DEET. MDA, EA, and DEET inhibited Aedes aegypti from flying towards skin odor while BA had no such effect. Conversely, MDA had no effect on oviposition while EA, BA, and DEET deterred oviposition, with the strongest effect observed for BA. Thus, we confirm that EA and DEET are generally repellent, while MDA is repellent only in a host-seeking context, and BA is deterrent only in an oviposition context. These compounds appear of potential use in mosquito control programs.

  17. Transgenic expression of the Aedes aegypti CYP9J28 confers pyrethroid resistance in Drosophila melanogaster

    NARCIS (Netherlands)

    N. Pavlidi; M. Monastirioti; P. Daborn; T. Van Leeuwen; J. Vontas

    2012-01-01

    The emergence and spread of insecticide resistance in mosquitoes, such as the major vector of dengue and yellow fever Aedes aegypti, is a major public health problem. A number of studies have been conducted to-date aiming to identify specific molecular changes that are associated with the phenotype,

  18. Dengue virus 3 genotype I in Aedes aegypti mosquitoes and eggs, Brazil, 2005-2006.

    Science.gov (United States)

    Vilela, Ana P P; Figueiredo, Leandra B; dos Santos, João R; Eiras, Alvaro E; Bonjardim, Cláudio A; Ferreira, Paulo C P; Kroon, Erna G

    2010-06-01

    Dengue virus type 3 genotype I was detected in Brazil during epidemics in 2002-2004. To confirm this finding, we identified this virus genotype in naturally infected field-caught Aedes aegypti mosquitoes and eggs. Results showed usefulness of virus investigations in vectors as a component of active epidemiologic surveillance. PMID:20507754

  19. Ovicidal activity of Metarhizium brunneum (Mb F52) on dengue fever vector, Aedes aegypti

    Science.gov (United States)

    The ovicidal activity of Metarhizium brunneum F52 (Mb F52) grown from granules was evaluated against Aedes aegypti eggs over time. Survival of larvae from treated eggs was significantly less when compared with untreated eggs at 7, 10 and 14 days post treatment. Only 27 % of treated eggs produced vi...

  20. Ovicidal activity of Ageratina adenophora (Family: Asteraceae) against dengue vector, Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    To determine the ovicidal efficacy of different solvent leaf extracts of Ageratina adenophora against dengue vector Aedes aegypti . Methods: The ovicidal efficacy of the crude leaf extracts of A. adenophora with five different solvents (hexane, benzene, chloroform, ethyl acetate, methanol) and was ...

  1. Resistance Status of Aedes aegypti to Cypermethrin through Susceptibility Method in Cimahi City

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    Yuneu Yuliasih

    2011-06-01

    Full Text Available Vector control of dengue usually doing by using insecticides, whether by government or insecticides used in household. Using to much insecticides for long time can caused resistence of mosquito. This research aim to know resistance status of Aedes aegypti from endemic rural in district Cimahi to cypermethrin (synthetic pyretroid. Resistance status knowing by susceptibility methods (WHO standard with using impregnated paper that containing cypermethrin 0.2% and 0.4%. Aedes aegypti spread by it for 15, 30, 45 and 60 minutes. Number of mortality count by percentage death mosquito in each time and each concentration of cypermethrin. Data interpreted by WHO standard, which percentage of death mosquito <80% is resistance, between 80-98% is tolerance and 99-100% is susceptible. Aedes aegypti from endemic rural in district Cimahi showed resistance of cypermethrin 0.2% and 0.4%. This result showed that all mosquito still alive after 15 minutes spreading by cypermethrin 0.2%, and only 6.7% mosquito death in cypermethrin 0.4%. After 30 minutes, death mosquito counted 46.7% in cypermethrin 0.2% and 73.3% in 0.4%. 46.7% mosquito was death in 45 and 60 minutes spreading by cypermethrin 0.2% and 73.3% in 0.4%. The result showed resistance ratio (RR50 of mosquito is 4.6. Aedes aegypti from endemic rural in district Cimahi showed a resistance to cypermethrin 0.2% and 0.4%.

  2. Chikungunya Virus in Febrile Humans and Aedes aegypti Mosquitoes, Yucatan, Mexico

    Science.gov (United States)

    Cigarroa-Toledo, Nohemi; Blitvich, Bradley J.; Cetina-Trejo, Rosa C.; Talavera-Aguilar, Lourdes G.; Baak-Baak, Carlos M.; Torres-Chablé, Oswaldo M.; Hamid, Md-Nafiz; Friedberg, Iddo; González-Martinez, Pedro; Alonzo-Salomon, Gabriela; Rosado-Paredes, Elsy P.; Rivero-Cárdenas, Nubia; Reyes-Solis, Guadalupe C.; Farfan-Ale, Jose A.; Garcia-Rejon, Julian E.

    2016-01-01

    Chikungunya virus (CHIKV) was isolated from 12 febrile humans in Yucatan, Mexico, in 2015. One patient was co-infected with dengue virus type 1. Two additional CHIKV isolates were obtained from Aedes aegypti mosquitoes collected in the homes of patients. Phylogenetic analysis showed that the CHIKV isolates belong to the Asian lineage. PMID:27347760

  3. The effect of chitin synthesis inhibitors on the development of Brugia malayi in Aedes aegypti.

    Science.gov (United States)

    Mohapatra, R; Ranjit, M R; Dash, A P

    1996-09-01

    Two chitin synthesis inhibitors (CSIs) viz., triflumuron and hexaflumuron interfere++ with the development of Brugia malayi in Aedes aegypti (a black-eyed Liverpool strain). The development of B. malayi was slow in both the treated populations and the infection rate, infectivity rate and L3 load per mosquito decreased significantly (P triflumuron. PMID:8984113

  4. VERTICAL TRANSMISSION OF DENGUE VIRUS IN Aedes aegypti COLLECTED IN PUERTO IGUAZÚ, MISIONES, ARGENTINA

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    Manuel Espinosa

    2014-04-01

    Full Text Available A finding of vertical transmission of the DEN 3 virus in male specimens of Aedes aegypti, collected in the 2009 fall-winter period, in Puerto Iguazú city, Misiones, Argentina, using the RT-PCR technique in a 15-specimen pool is reported. This result is analyzed within the context of the epidemiological situation of Argentina's northeast border.

  5. Infection of adult Aedes aegypti and Ae. albopictus mosquitoes with the entomopathogenic fungus Metarhizium anisopliae

    NARCIS (Netherlands)

    Scholte, E.J.; Takken, W.; Knols, B.G.J.

    2007-01-01

    This study describes a laboratory investigation on the use of the insect-pathogenic fungus Metarhizium anisopliae against adult Aedes aegypti and Ae. albopictus mosquitoes. At a dosage of 1.6 × 1010 conidia/m2, applied on material that served as a mosquito resting site, an average of 87.1 ± 2.65% of

  6. Synthesis and larvicidal and adult topical activity of some hydrazide-hydrazone derivatives against Aedes aegypti

    Science.gov (United States)

    A series of novel hydrazide-hydrazone derivatives were synthesized and evaluated for their larvicidal and adult topical activity against Aedes aegypti. The proposed structures of all the synthesized compounds were confirmed using elemental analysis, UV, IR, 1H-NMR, 13C-NMR and mass spectroscopy. Com...

  7. Toxicity of Cephalaria species and their individual constituents against Aedes aegypti

    Science.gov (United States)

    Crude acetone and ethanol extracts of the aerial parts of 21 Cephalaria species collected from Turkey were investigated for larvicidal and adult topical activity against Aedes aegypti. The ethanol extracts from C. elazigensis var. purpurea, C. anatolica, and C. elmaliensis possessed the highest mort...

  8. Aerial ULV application of Dibrom against Aedes aegypti in simulated urban and rural residences

    Science.gov (United States)

    Reaching endophilic Aedes aegypti mosquito vectors of dengue located in human residences with aerial ULV pesticide applications is a prominent complication in operational wide area public health mosquito control activities. We conducted separate trials with a military C-130 fixed wing aircraft fitte...

  9. Mosquito activity of a series of chalcones and 2-pyrazoline derivatives against Aedes aegypti

    Science.gov (United States)

    Aedes aegypti (L.) (Diptera: Culicidae) transmit pathogens to humans, leading to diseases such as yellow fever and dengue fever. Repellents and insecticides are two common interventions to reduce mosquito biting and thereby disease risk. However, overreliance on a chemical or class of chemicals c...

  10. Effect of triflumuron, a chitin synthesis inhibitor, on Aedes aegypti, Aedes albopictus and Culex quinquefasciatus under laboratory conditions

    OpenAIRE

    Belinato, Thiago Affonso; Martins, Ademir Jesus; Lima, José Bento Pereira; Valle, Denise

    2013-01-01

    Background Resistance to traditional insecticides represents a threat to the control of disease vectors. The insect growth regulators (IGR) are a potential alternative to control mosquitoes, including resistant populations. The chitin synthesis inhibitors (CSI) are IGRs, which interfere with the insect molting process and represent one major class of compounds against Aedes aegypti populations resistant to the larvicide organophosphate temephos. In the present study, we evaluated the efficacy...

  11. Spatial mapping of gene expression in the salivary glands of the dengue vector mosquito, aedes aegypti

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    Paolucci Pimenta Paulo

    2011-01-01

    Full Text Available Abstract Background Aedes aegypti mosquitoes are the main vectors of dengue viruses to humans. Understanding their biology and interactions with the pathogen are prerequisites for development of dengue transmission control strategies. Mosquito salivary glands are organs involved directly in pathogen transmission to vertebrate hosts. Information on the spatial distribution of gene expression in these organs is expected to assist in the development of novel disease control strategies, including those that entail the release of transgenic mosquitoes with impaired vector competence. Results We report here the hybridization in situ patterns of 30 transcripts expressed in the salivary glands of adult Ae. aegypti females. Distinct spatial accumulation patterns were identified. The products of twelve genes are localized exclusively in the proximal-lateral lobes. Among these, three accumulate preferentially in the most anterior portion of the proximal-lateral lobe. This pattern revealed a salivary gland cell type previously undescribed in Ae. aegypti, which was validated by transmission electron microscopy. Five distinct gene products accumulate in the distal-lateral lobes and another five localize in the medial lobe. Seven transcripts are found in the distal-lateral and medial lobes. The transcriptional product of one gene accumulates in proximal- and distal-lateral lobes. Seven genes analyzed by quantitative PCR are expressed constitutively. The most abundant salivary gland transcripts are those localized within the proximal-lateral lobes, while previous work has shown that the distal-lateral lobes are the most active in protein synthesis. This incongruity suggests a role for translational regulation in mosquito saliva production. Conclusions Transgenic mosquitoes with reduced vector competence have been proposed as tools for the control of dengue virus transmission. Expression of anti-dengue effector molecules in the distal-lateral lobes of Ae

  12. PENENTUAN STATUS RESISTENSI Aedes aegypti DENGAN METODE SUSCEPTIBILITY DI KOTA CIMAHI TERHADAP CYPERMETHRIN

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    Firda Yanuar Pradani

    2013-12-01

    Full Text Available ABSTRACT Background:  vector control of DBD usually doing by using insecticides, whether by government or insecticides used in household.  Using to much insecticides for long time can caused resistence of mosquito.  This research aim to know resistance status of Aedes aegypti from endemic rural in district Cimahi to cypermethrin (synthetic pyretroid. Methods:  resistance status knowing by susceptibility methods (WHO standard with usingimpregnated paper that containing cypermethrin 0,2% and 0,4%.  Aedes aegypti spread by it for 15, 30, 45 and 60 minutes.  Number of mortality count by percentage death mosquito in each time and each concentration of cypermethrin.  Data interpreted by WHO standard, which percentage ofdeath mosquito <80% is resistance, between 80-98% is tolerance and 99-100% is susceptible. Result: Aedes aegypti from endemic rural in district Cimahi showed resistance of cypermethrin 0,2% and 0,4%. This result showed that all mosquito still alive after 15 minutes spreading bycypermethrin 0,2%, and only 6,7% mosquito death in cypermethrin 0,4%.  After 30 minutes, death mosquito counted 46,7% in cypermethrin 0,2% and 73,3% in 0,4%.  46,7% mosquito was death in 45 and 60 minutes spreading by cypermethrin 0,2% and 73,3% in 0,4%.  The resultshowed resistance ratio (RR50 of mosquito is 4,6.Conclution: Aedes aegypti from endemic rural in distric Cimahi showed a resistance to cypermethrin 0,2% and 0,4%.Key words:  Aedes aegypti, cypermethrin, resistance, Cimahi district ABSTRAK Latar Belakang: pengendalian vektor DBD biasanya dilakukan dengan menggunakan insektisida, apakah oleh pemerintah atau insektisida yang digunakan dalam rumah tangga. penggunaan insektisida dalam jumlah yang banyak dan waktu yang lama dapat menyebabkan nyamuk resisten.Penelitian ini bertujuan untuk mengetahui status resistensi nyamuk Aedes aegypti dari daerah pedesaan endemik di kabupaten Cimahi terhadap cypermethrin (pyretroid sintetis. Metode : mengetahui

  13. Mitochondrial physiology in the major arbovirus vector Aedes aegypti: substrate preferences and sexual differences define respiratory capacity and superoxide production.

    Science.gov (United States)

    Soares, Juliana B R Correa; Gaviraghi, Alessandro; Oliveira, Marcus F

    2015-01-01

    Adult females of Aedes aegypti are facultative blood sucking insects and vectors of Dengue and yellow fever viruses. Insect dispersal plays a central role in disease transmission and the extremely high energy demand posed by flight is accomplished by a very efficient oxidative phosphorylation process, which take place within flight muscle mitochondria. These organelles play a central role in energy metabolism, interconnecting nutrient oxidation to ATP synthesis, but also represent an important site of cellular superoxide production. Given the importance of mitochondria to cell physiology, and the potential contributions of this organelle for A. aegypti biology and vectorial capacity, here, we conducted a systematic assessment of mitochondrial physiology in flight muscle of young adult A. aegypti fed exclusively with sugar. This was carried out by determining the activities of mitochondrial enzymes, the substrate preferences to sustain respiration, the mitochondrial bioenergetic efficiency and capacity, in both mitochondria-enriched preparations and mechanically permeabilized flight muscle in both sexes. We also determined the substrates preferences to promote mitochondrial superoxide generation and the main sites where it is produced within this organelle. We observed that respiration in A. aegypti mitochondria was essentially driven by complex I and glycerol 3 phosphate dehydrogenase substrates, which promoted distinct mitochondrial bioenergetic capacities, but with preserved efficiencies. Respiration mediated by proline oxidation in female mitochondria was strikingly higher than in males. Mitochondrial superoxide production was essentially mediated through proline and glycerol 3 phosphate oxidation, which took place at sites other than complex I. Finally, differences in mitochondrial superoxide production among sexes were only observed in male oxidizing glycerol 3 phosphate, exhibiting higher rates than in female. Together, these data represent a significant step

  14. KERENTANAN LARVA AEDES AEGYPTI TERHADAP TEMEFOS DI TIGA KELURAHAN ENDEMIS DEMAM BERDARAH DENGUE KOTA SUKABUMI

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    Hubullah Fuadzy

    2015-04-01

    Full Text Available AbstractResistance of Aedes aegypti larvae against temephos influeneed the efforts of Dengue Fever vector control . The purpose of this study was to determine the status of susceptibility of Ae. aegypti larvae against temephos in three Dengue Fever endemic areas in Sukabumi. Design laboratory experiment with random design. approach group. Sample of Ae. aegypti larvae instar 3 and 4 had been taken from Subdistrict Baros, Sriwedari, Nangeleng. Susceptibility test, in performed according to WorldHealth Organization (WHO. Result of this study, according to WHO recommended concentration 0.02 ppm showed thatlarvae in Subdistrict Baros, Sriwedari, and Nangeleng still susteptible against temephos with Ae. aegypti larvae mortality of 100%. Effective concentration 50% (LC50dan 99% (LC99 in subdistrict Baros were 0.00169 and 0,01711; Sriwedari were 0.00125 and 0.00313: Nanggeleng were 0.00214 and 0.00762 (ppm.respectinely Higher resistance ratio occur to Subdistrict Baros with level resistance of RR99 7.34. In Conclution, temephos still effective to beused as larvicide for vector control in those three endemic of Dengue Fever in Sukabumi.Keywords : Susceptibility, Aedes aegypty, Temephos, SukabumiAbstrakResistensi larva Aedes aegypti terhadap temefos dapat mempengaruhi upaya pengendalian vektor Demam Berdarah Dengue. Tujuan penelitian adalah menentukan status kerentanan larva Ae. aegypti terhadap temefos di tiga Kelurahan endemis Demam Berdarah Dengue Kota Sukabumi. Jenis penelitian adalah eksperimental laboratorium dengan pendekatan rancangan acak kelompok. Sampel adalah larva Ae. aegypti instar 3 dan 4 dari Kelurahan Baros, Sriwedari, dan Nangeleng. Uji kerentanan dilakukan berdasarkan metode Bioassay WHO. Hasil penelitian berdasarkan katagori konsentrasi yang dianjurkan WHO sebesar 0,02 ppm menunjukkan bahwa Kelurahan Baros, Sriwedari, dan Nangeleng masih rentan terhadap temefos dengan kematian larva Ae. aegypti 100%. Konsentrasi efektif 50% (LC50 dan

  15. Multiple QTL Determine Dorsal Abdominal Scale Patterns in the Mosquito Aedes aegypti.

    Science.gov (United States)

    Mori, Akio; Tsuda, Yoshio; Takagi, Masahiro; Higa, Yukiko; Severson, David W

    2016-09-01

    The mosquito, Aedes aegypti (L.) originated in Sub-Saharan Africa as a dark form sylvan species (A. aegypti formosus). Evolution of A. aegypti aegypti type form as a human commensal facilitated its colonization of most semitropical and tropical areas. We investigated the genetic basis for abdominal white scale presence that represents the diagnostic for sylvan A. aegypti formosus (scales absent), from type form (scales present) and A. aegypti queenslandensis form (dense scaling). We performed quantitative trait locus (QTL) mapping using 3 criteria for scale patterns among 192 F1 intercross progeny from matings between a queenslandensis type and an aegypti type form. Results identified 3 QTL determining scale patterns and indicated that classification criteria impact robustness of QTL LOD support. Dark- and light-colored forms exist in sympatry, but vary in multiple phenotypic characteristics, including preferences for vertebrate host, oviposition container, house-entering behavior, and dengue vector competence. Markers associated with 2 QTL regions reflected major reductions in recombination frequencies compared with the standard type form linkage map, suggestive of inversion polymorphisms associated with observed linkage disequilibrium between type-specific characteristics. Understanding the genic basis for differences in A. aegypti forms could inform efforts to develop new mosquito and arboviral disease control strategies. PMID:27130203

  16. Chikungunya virus susceptibility & variation in populations of Aedes aegypti (Diptera: Culicidae mosquito from India

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    Mangesh D Gokhale

    2015-01-01

    Full Text Available Background & objectives: Although having immense clinical relevance, yet only a few studies have been targeted to understand the chikungunya virus (CHIKV susceptibility and growth in Aedes aegypti populations from India. This study was undertaken to investigate CHIKV susceptibility and growth kinetics in Ae. aegypti along with genetic heterogeneity of Ae. aegypti populations. Methods: Dose dependent CHIKV susceptibility and growth kinetic studies for three CHIKV strains reported from India were carried out in Ae. aegypti mosquito populations. The phenotypic variation and genetic heterogeneity in five Ae. aegypti populations were investigated using multivariate morphometrics and allozyme variation studies. Results: The dissemination and growth kinetics studies of the three CHIKV strains showed no selective advantage for a particular strain of CHIKV in Ae. aegypti. At 100 per cent infection rate, five geographic Ae. aegypti populations showed differences in dissemination to three CHIKV strains. Morphometric studies revealed phenotypic variation in all the studied populations. The allelic frequencies, F statistics, and Nei′s genetic identity values showed that genetic differences between the populations were small, but significant. Interpretation & conclusions: The results obtained in this study suggest that genetic background of the vector strongly influences the CHIKV susceptibility in Ae. aegypti.

  17. Improving the effectiveness of three essential oils against Aedes aegypti (Linn.) and Anopheles dirus (Peyton and Harrison).

    Science.gov (United States)

    Auysawasdi, Nutthanun; Chuntranuluck, Sawitri; Phasomkusolsil, Siriporn; Keeratinijakal, Vichien

    2016-01-01

    Repellency of essential oil extracted from Curcuma longa, Eucalyptus globulus, and Citrus aurantium at various concentrations (5, 10, 15, 20, and 25 %) with and without 5 % vanillin was evaluated against female mosquitoes: Aedes aegypti and Anopheles dirus. The comparisons were made with a commercial chemical repellent (N,N-diethyl-3-methylbenzamide (DEET) 25 % w/w; KOR YOR 15) by arm in cage method. It was found that the essential oils with 5 % vanillin gave the longest lasting period against two mosquitoes as follows: Curcuma longa gave 150 min for Ae. aegypti, 480 min for An. dirus; Eucalyptus globulus gave 144 min for Ae. aegypti, 390 min for An. dirus; and Citrus aurantium gave 120 min for Ae. aegypti, 360 min for An. dirus. The 25 % Curcuma longa essential oil exhibited the best efficiency as equal as a commercial repellent (480 min against An. dirus). Vanillin can extend the period of time in protection against the two mosquitoes. This study indicates the potential uses of the essential oils (Curcuma longa, Eucalyptus globulus, and Citrus aurantium) with vanillin as natural mosquito repellents. PMID:26358103

  18. A virulent Wolbachia infection decreases the viability of the dengue vector Aedes aegypti during periods of embryonic quiescence.

    Directory of Open Access Journals (Sweden)

    Conor J McMeniman

    Full Text Available A new approach for dengue control has been proposed that relies on life-shortening strains of the obligate intracellular bacterium Wolbachia pipientis to modify mosquito population age structure and reduce pathogen transmission. Previously we reported the stable transinfection of the major dengue vector Aedes aegypti with a life-shortening Wolbachia strain (wMelPop-CLA from the vinegar fly Drosophila melanogaster. Here, we report a further characterization of the phenotypic effects of this virulent Wolbachia infection on several life-history traits of Ae. aegypti. Minor costs of wMelPop-CLA infection for pre-imaginal survivorship, development and adult size were found. However, we discovered that the wMelPop-CLA infection dramatically decreased the viability of desiccated Ae. aegypti eggs over time. Similarly, the reproductive fitness of wMelPop-CLA infected Ae. aegypti females declined with age. These results reveal a general pattern associated with wMelPop-CLA induced pathogenesis in this mosquito species, where host fitness costs increase during aging of both immature and adult life-history stages. In addition to influencing the invasion dynamics of this particular Wolbachia strain, we suggest that the negative impact of wMelPop-CLA on embryonic quiescence may have applied utility as a tool to reduce mosquito population size in regions with pronounced dry seasons or in regions that experience cool winters.

  19. Susceptibility to temephos, permethrin and deltamethrin ofAedes aegypti (Diptera:Culicidae) from Muang district, Phitsanulok Province, Thailand

    Institute of Scientific and Technical Information of China (English)

    Damrongpan Thongwat; Nophawan Bunchu

    2015-01-01

    Objective:To investigate the susceptibility to temephos, permethrin and deltamethrin ofAedes aegypti(Ae. aegypti), collected from areas with high incidence of dengue hemorrhagic fever cases inPhitsanulokProvince,Thailand.Methods:TheF1 progenies ofAe. aegypti colony, originated from five sub-districts includingAranyik,HuaRo,NaiMuang,BanKrang andThaPho, were used in the bioassays following the procedures ofWorldHealthOrganization.For larval bioassay, the late third or early fourth-instar larvae were tested with different concentrations of temephos. For adult bioassay, the females were exposed to0.75% permethrin or0.05% deltamethrin.LC50 value and mortality rate were analyzed to compare the insecticide susceptibility of the larvae and the adults in each area, respectively. Results:TheLC50 value of temephos for the larvae from Aranyik,HuaRo,NaiMuang,BanKrang andThaPho sub-districts was0.017,0.017,0.026,0.061, and0.113 ppm, respectively.For permethrin, the highest mortality rate(86.84%) was found in the mosquitoes fromAranyik but the others were more resistant with the lower mortality rates(16.00-42.67%).The adult mortality rates after exposing to deltamethrin were higher(82.34-98.67%) in all areas.Conclusions:Ae. aegypti larvae were still susceptible to temephos.Conversely, most tested adults tended to resist the permethrin and deltamethrin.

  20. Estabelecimento de metodologia para alimentação de Aedes aegypti (Diptera-Culicidae em camundongos swiss e avaliação da toxicidade e do efeito residual do óleo essencial de Tagetes minuta L (Asteraceae em populações de Aedes aegypti Establishment of the feeding methodology of Aedes aegypti (Diptera-Culicidae in Swiss mice and evaluation of the toxicity and residual effect of essential oil from Tagetes minuta L (Asteraceae, in populations of Aedes aegypti

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    Waldemir Pereira Lima

    2009-12-01

    Full Text Available Objetivou-se desenvolver um procedimento de alimentação de fêmeas de Aedes aegypti que não cause estresse em camundongo swiss e avaliar a toxicidade e o efeito residual do óleo essencial de Tagetes minuta L (Asteraceae em populações de Aedes aegypti. Camundongos anestesiados: um observado tempo de sedação e outro colocado em gaiola para alimentação de fêmeas. Óleo essencial, diluído em acetona, foi utilizado em bioensaios para avaliação das concentrações letais em larvas de Bauru, SP e São José do Rio Preto, SP, respectivamente, sensíveis e resistentes ao temephos. Os dados obtidos foram comparados com a cepa Rockefeller-EUA. O procedimento com camundongos foi aprovado. Não houve diferença entre as populações quanto à susceptibilidade a Tagetes minuta e os ensaios demonstraram CL50 de 0,24, 0,25 e 0,21mL L-1 e CL99,9 em 0,35, 0,39 e 0,42mL L-1, respectivamente, para Rockfeller, Bauru e São José do Rio Preto. Não foi observado efeito residual da solução.The objectives here were to develop a procedure for feeding females of Aedes aegypti that does not cause stress in Swiss mice and to evaluate the toxicity and residual effect of essential oil from Tagetes minuta L. (Asteraceae in Aedes aegypti populations. Two mice were anesthetized: one was used to observe the duration of sedation and the other was placed in a cage to feed the female mosquitoes. Essential oil was diluted in acetone and used in bioassays to assess the lethal concentrations in larvae from the Cities of Bauru (SP and São José do Rio Preto (SP that were sensitive and resistant to temephos, respectively. The data obtained were compared with the American Rockefeller strain. The procedure with mice was approved. There was no difference between the populations regarding susceptibility to Tagetes minuta, and the assays showed LC50 of 0.24, 0.25 and 0.21 ml/l and LC99.9 of 0.35, 0.39 and 0.42 ml/l, for Rockefeller, Bauru and São José do Rio Preto

  1. Aedes aegypti midgut early trypsin is post-transcriptionally regulated by blood feeding.

    Science.gov (United States)

    Noriega, F G; Pennington, J E; Barillas-Mury, C; Wang, X Y; Wells, M A

    1996-02-01

    Early trypsin is a female-specific protease present in the Aedes aegypti midgut during the first hours after ingestion of a blood meal. Early trypsin gene expression was studied by Northern blot analysis. The early trypsin mRNA, absent in larvae, pupae and newly emerged females, reaches detectable levels at 24 h post-emergence and attains a maximum level at an adult age of 4-7 days. After the first week there is a decrease in the steady-state level of the transcript, but it remains readily detectable for up to a month after emergence. Despite the high levels of early trypsin mRNA present in the midgut of the unfed female, translation of the early trypsin mRNA occurs only after a blood or a protein meal. Early trypsin mRNA levels rapidly decrease during the first 24 h after feeding, but the steady-state level of the transcript rises again at the end of the blood digestion cycle (60 h), as the mosquito prepares for a second blood meal. PMID:8630532

  2. Aedes aegypti and Aedes albopictus (Diptera: Culicidae: coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization

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    Josiane Somariva Prophiro

    2011-06-01

    Full Text Available INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion. Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina presented survival when exposed to the organophosphate temephos.

  3. Evidence for natural vertical transmission of chikungunya viruses in field populations of Aedes aegypti in Delhi and Haryana states in India-a preliminary report.

    Science.gov (United States)

    Jain, Jaspreet; Kushwah, Raja Babu S; Singh, Shashi S; Sharma, Anil; Adak, Tridibes; Singh, Om P; Bhatnagar, Raj Kamal; Subbarao, Sarala K; Sunil, Sujatha

    2016-10-01

    Aedes aegypti and Aedes albopictus are principal vectors for the transmission of chikungunya virus (CHIKV). India is a hub for both dengue and chikungunya infections and there are several reports of co-infection of dengue and chikungunya virus in the clinical scenario. The present pilot entomological survey was conducted to evaluate vertical transmission of CHIKV in Aedes field populations. Aedes immature (larvae and pupae) collection was done in 2012, over a period of six months from selected sites in Delhi and Haryana, India. The immatures collected were reared for adult emergence and species identification was done. A. aegypti male and female mosquitoes were separated and pooled collection spot-wise, RNA extracted and RT PCR performed to test for the presence of CHIKV in the pools. Container index (CI) and minimum infection rate (MIR) were estimated. From study areas that tested positive for CHIKV, adult collections were made and females upon feeding on uninfected blood in laboratory were allowed to lay eggs. The progeny that emerged from these field-collected mothers were tested for CHIKV presence. Our pilot survey showed the existence of A. aegypti population even during peak summer season in a few foci which eventually helped the mosquitoes to tide over adverse environmental conditions and with the start of rainfall, the population exploded within a short period of time. Immatures collected from field and progeny of adults collected from the field were CHIKV positive demonstrating the presence of vertical transmission of chikungunya virus in field population of A. aegypti. The present study further demonstrates the importance of identifying permanent breeding sites for proper Aedes species control. PMID:27282096

  4. An in vitro bioassay for the quantitative evaluation of mosquito repellents against Stegomyia aegypti (=Aedes aegypti) mosquitoes using a novel cocktail meal.

    Science.gov (United States)

    Huang, T-H; Tien, N-Y; Luo, Y-P

    2015-09-01

    To assess the efficacy of new insect repellents, an efficient and safe in vitro bioassay system using a multiple-membrane blood-feeding device and a cocktail meal was developed. The multiple-membrane blood-feeding device facilitates the identification of new insect repellents by the high-throughput screening of candidate chemicals. A cocktail meal was developed as a replacement for blood for feeding females of Stegomyia aegypti (=Aedes aegypti) (L.) (Diptera: Culicidae). The cocktail meal consisted of a mixture of salt, albumin and dextrose, to which adenosine triphosphate was added to induce engorging. Feeding rates of St. aegypti on the cocktail meal and pig blood, respectively, did not differ significantly, but were significantly higher than the feeding rate on citrate phosphate dextrose-adenine 1 (CPDA-1) solutions, which had been used to replace bloodmeals in previous repellent assays. Dose-dependent biting inhibition rates were analysed using probit analysis. The RD(50) (the dose producing 50% repellence of mosquito feeding) values of DEET, citronella, carvacrol, geraniol, eugenol and thymol were 1.62, 14.40, 22.51, 23.29, 23.83 and 68.05 µg/cm(2), respectively. PMID:25828787

  5. Leaf extracts of Melia azedarach Linnaeus (Sapindales: Meliaceae act as larvicide against Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae Extratos de folhas de Melia azedarach Linnaeus (Sapindales: Meliaceae atuam como larvicida de Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2008-12-01

    Full Text Available The objective of this study was to compare the larvicidal effect of hydroethanolic extracts of fresh and dry leaves of Melia azedarach Linnaeus (Sapindales: Meliaceae on Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae. All the extracts evaluated induced mortality among the third and fourth instar larvae of Aedes aegypti after 24 and 48 hours of exposure to the products. Although previous studies had demonstrated the action of seeds and fruits of Melia azedarach against the larvae of different Aedes aegypti populations, the present report is the first to show the larvicidal effect of the fresh and dry leaves of this plant.O objetivo deste trabalho foi comparar o efeito larvicida de extratos hidro-etanólicos de folhas verdes e secas de Melia azedarach Linnaeus (Sapindales: Meliaceae em Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae. Todos os extratos avaliados induziram mortalidade em larvas de 3º e 4º estágios de Aedes aegypti, após 24 e 48 horas de exposição aos produtos. Embora estudos prévios tenham demonstrado a ação de sementes e frutos de Melia azedarach em larvas de diferentes populações de Aedes aegypti, o presente estudo é o primeiro a reportar o efeito larvicida de folhas verdes e secas desta planta.

  6. Competência de peixes como predadores de larvas de Aedes aegypti, em condições de laboratório Efficacy of fish as predators of Aedes aegypti larvae, under laboratory conditions

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    Luciano Pamplona de Góes Cavalcanti

    2007-08-01

    Full Text Available OBJETIVO: Avaliar a competência de peixes na predação de larvas de Aedes aegypti, em condições de laboratório. MÉTODOS: Foram testados machos e fêmeas de cinco espécies de peixe. Os testes de predação duravam cinco semanas para cada espécie. Cada ensaio compreendia quatro caixas testes e quatro caixas controles. Das caixas controle, duas tinham somente um peixe e as outras duas, apenas larvas. Cada caixa teste continha um peixe e larvas. Na primeira semana foram expostas 100 larvas em cada caixa, e a cada semana acrescentavam-se 100 larvas por caixa/dia, até se obter um máximo de 500 larvas/dia. Comprimento e peso dos peixes foram medidos semanalmente. RESULTADOS: Foram utilizadas 369.000 larvas no total. O Trichogaster trichopteros foi a única espécie em que ambos os sexos predaram 100% das larvas oferecidas. O Betta splendens deixou de predar apenas 15 larvas. Machos do Poecilia reticulata apresentaram baixa capacidade larvófaga quando comparados às fêmeas da mesma espécie. Em relação ao peso e tamanho o Betta splendens mostrou-se capaz de predar 523 larvas/grama/dia. CONCLUSÕES: Fêmeas e machos de Trichogaster trichopteros e de Astyanax fasciatus, e fêmeas de Betta splendens e de Poecillia sphenops foram os peixes que apresentaram maior competência para predar as larvas. Embora com competência menor, machos de Poecillia sphenops e fêmeas de Poecilia reticulata foram capazes de eliminar o número de larvas de Aedes aegypti que possam emergir durante 24 horas num criadouro, em condições naturais. Machos de Poecilia reticulata não foram predadores eficazes.OBJECTIVE: To evaluate the efficacy of fish as predators of the Aedes aegypti larvae in laboratory conditions. METHODS: The male and female of five different fish were included in the experiment. The tests to measure their consumption ability lasted five weeks for each species. Each trial involved four test tanks and four control tanks. Two control tanks

  7. Resistance of Aedes aegypti from the state of São Paulo, Brazil, to organophosphates insecticides

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    Macoris Maria de Lourdes G

    2003-01-01

    Full Text Available Since the reintroduction of Aedes aegypti in the state of São Paulo, in the middle of the 1980-decade, organophosphate insecticides are being used to control the dengue vector. In 1996, an annual program for monitoring the susceptibility of Ae. aegypti to the insecticides was implemented. Some of the results of this monitoring program are presented. Ae. aegypti populations from ten localities have been submitted to bioassays with the diagnostic dose of temephos and fenitrothion. Only two (Marília and Presidente Prudente remain susceptible to both insecticides and one (Santos exhibits true resistance. Ae. aegypti from the remaining localities showed an incipient altered susceptibility. Resistance ratios varied from 1.2 to 2.9 for temephos and from 1.5 to 3.2 to fenitrothion, indicating moderate levels of resistance. Biochemical assays did not detect alterations in the enzyme acetilcholinesterase, but indicated that resistance is associated with esterases.

  8. PATOGENITAS CENDAWAN BEAUVERIA BASSIANA TERHADAP LARVA NYAMUK AEDES AEGYPTI DAN CULEX PIPIENS QUINQUEFASCIATUS DI LABORATORIUM

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    Amrul Munif

    2012-09-01

    Full Text Available The capability of Beauveria bassiana fungus to kill mosquito larvae was challenged with Aedes aegypti and Culex pipiens quinquefasciatus in a study conducted at the entomology laboratory of the Health Ecology Research Centre. Cx. p. quinquefeasciatus was more sensitive compared to Ae. aegypti to the B. bassiana strain from Sukamandi (West Java, which is probably due to the mosquitoes behaviour and conidiospore larvacidal effect. Conidia dust application, with a dosage of 2.2 mglliter, to water surface, within 48 hours was able to kill almost all the Cx. p. quinquefasciatus. However a dosage of 4 mglliter was required to kill all the Ae.aegypti. And a dosage of 1.3 mg conidiospore I liter is able to kill 50% Cx. p. quinquefasciatus. It seems that B. bassiana has greater capability to eradicate Cx. p. quinquefasciatus compared to Ae. aegypti

  9. Monooxygenase activitity in Aedes aegypti population in Tembalang subdistrict, Semarang city

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    Dyah Widiastuti

    2015-06-01

    Full Text Available Dengue Haemorrhagic Fever (DHF is a major health problem in Tembalang sub district, Semarang City. Fogging with insecticide applications was done frequently as an effort to control Dengue vectors. The use of insecticides from the same class in a long time can lead to resistance in mosquitos’ population. The research aimed to observe the activity of monooxygenases in Aedes aegypti populations in Tembalang Subdistrict, Semarang. The study was conducted during February-November 2014 with a cross-sectional design in 10 villages in Tembalang Subdistirict, Semarang City. Field strains of Ae. aegypti eggs were collected using ovitraps. The collected eggs were grown under standard condition to adult mosquitoes. Mosquitos’ homogenate were stored at -85C and used for biochemical assays. The results showed there was increased monooxygenases activity in Ae. aegypti populations. Resistance to synthetic pyrethroid insecticide in Ae. aegypti mosquitoes population in Tembalang Subdistrict might be caused by the mechanism of detoxification enzymes in particular monooxygenases

  10. Oral Susceptibility to Yellow Fever Virus of Aedes aegypti from Brazil

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    Ricardo Lourenço-de-Oliveira

    2002-04-01

    Full Text Available The oral susceptibility to yellow fever virus was evaluated in 23 Aedes aegypti samples from Brazil. Six Ae. aegypti samples from Africa, America and Asia were also tested for comparison. Mosquito samples from Asia showed the highest infection rates. Infection rates for the Brazilian Ae. aegypti reached 48.6%, but were under 13% in 60% of sample tested. We concluded that although the low infection rates estimated for some Brazilian mosquito samples may not favor the establishment of urban cycle of yellow fever in some parts of the country, the founding of Ae. aegypti of noteworthy susceptibility to the virus in cities located in endemic and transition areas of sylvatic yellow fever, do pose a threat of the re-emergence of the urban transmission of the disease in Brazil.

  11. Nutritional and hormonal regulation of the TOR effector 4E-binding protein (4E-BP) in the mosquito Aedes aegypti

    OpenAIRE

    Roy, Saurabh G.; Raikhel, Alexander S.

    2012-01-01

    Mosquitoes require blood for egg development, and, as a consequence, they transmit pathogens of devastating diseases. Target of rapamycin (TOR) signaling is a key pathway linking blood feeding and egg development in the mosquito Aedes aegypti. We show that the regulation of the TOR effector translational repressor 4E-BP is finely tuned to the nutritional requirements of the female mosquito, and it occurs at transcriptional and post-translational levels. Immediately after blood feeding, 4E-BP ...

  12. Analyses of essential and edible oils, and constituents therein, as candidate repellents for the yellow fever mosquito Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Campbell, Cory James

    2009-01-01

    Some plant essential and edible oils repel mosquitoes but often quantitatively minor repellent constituents therein remain unknown. In gas chromatographic-electroantennographic detection (GC-EAD) analyses of catnip, cinnamon, citronella, cumin, eucalyptus, geranium, ginger, melissa, peppermint, rosemary, and thyme essential oils, 43 constituents elicited responses from antennae of female yellow fever mosquitoes, Aedes aegypti L. (Diptera: Culicidae). GC-EAD analyses of soybean oil (active ing...

  13. Two novel epistatic mutations (E1:K211E and E2:V264A) in structural proteins of Chikungunya virus enhance fitness in Aedes aegypti.

    Science.gov (United States)

    Agarwal, Ankita; Sharma, Ajay Kumar; Sukumaran, D; Parida, Manmohan; Dash, Paban Kumar

    2016-10-01

    Expansion of CHIKV outbreaks with appearance of novel mutations are reported from many parts of the world. Two novel mutations viz. E1:K211E and E2:V264A in background of E1:226A are recently identified from Aedes aegypti dominated areas of India. In this study, the role of these mutations in modulation of infectivity, dissemination and transmission by two different Aedes species was studied. Mutations were sequentially constructed in CHIKV genome and female Ae. aegypti and Aedes albopictus mosquitoes were orally infected with eight different CHIKV mutants. Double mutant virus containing E1:K211E and E2:V264A mutations in background of E1:226A revealed remarkably higher fitness for Ae. aegypti, as indicated by significant increase in virus infectivity (13 fold), dissemination (15 fold) and transmission (62 fold) compared to parental E1:226A virus. These results indicate that adaptive mutations in CHIKV are leading to efficient CHIKV circulation in Ae. aegypti endemic areas, contributing and sustaining the major CHIKV outbreaks. PMID:27423270

  14. On the Seasonal Occurrence and Abundance of the Zika Virus Vector Mosquito Aedes Aegypti in the Contiguous United States

    OpenAIRE

    Monaghan, Andrew J.; Morin, Cory W.; Steinhoff, Daniel F.; Wilhelmi, Olga; Hayden, Mary; Quattrochi, Dale A.; Reiskind, Michael; Alun L Lloyd; Smith, Kirk; Schmidt, Chris A.; Scalf, Paige E.; Ernst, Kacey

    2016-01-01

    Introduction: An ongoing Zika virus pandemic in Latin America and the Caribbean has raised concerns that travel-related introduction of Zika virus could initiate local transmission in the United States (U.S.) by its primary vector, the mosquito Aedes aegypti. Methods: We employed meteorologically driven models for 2006-2015 to simulate the potential seasonal abundance of adult Aedes aegypti for fifty cities within or near the margins of its known U.S. range. Mosquito abundance results were an...

  15. Spatial distribution and esterase activity in populations of Aedes (Stegomyia) aegypti (Linnaeus) (Diptera: Culicidae) resistant to temephos

    OpenAIRE

    Wanessa Porto Tito Gambarra; Walter Fabrício Silva Martins; Maurício Lilioso de Lucena Filho; Ingredy Meneses Cavalcanti de Albuquerque; Otávia Karla dos Santos Apolinário; Eduardo Barbosa Beserra

    2013-01-01

    INTRODUCTION: The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus) in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypti collected in municipalities of the State of Paraíba. METHODS: Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a...

  16. Gene flow, subspecies composition, and dengue virus-2 susceptibility among Aedes aegypti collections in Senegal.

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    Massamba Sylla

    Full Text Available BACKGROUND: Aedes aegypti, the "yellow fever mosquito", is the primary vector to humans of the four serotypes of dengue viruses (DENV1-4 and yellow fever virus (YFV and is a known vector of Chikungunya virus. There are two recognized subspecies of Ae. aegypti sensu latu (s.l.: the presumed ancestral form, Ae. aegypti formosus (Aaf, a primarily sylvan mosquito in sub-Saharan Africa, and Ae. aegypti aegypti (Aaa, found globally in tropical and subtropical regions typically in association with humans. The designation of Ae. aegypti s.l. subspecies arose from observations made in East Africa in the late 1950s that the frequency of pale "forms" of Ae. aegypti was higher in populations in and around human dwellings than in those of the nearby bush. But few studies have been made of Ae. aegypti s.l. in West Africa. To address this deficiency we have been studying the population genetics, subspecies composition and vector competence for DENV-2 of Ae. aegypti s.l. in Senegal. METHODS AND FINDINGS: A population genetic analysis of gene flow was conducted among 1,040 Aedes aegypti s.l. from 19 collections distributed across the five phytogeographic regions of Senegal. Adults lacking pale scales on their first abdominal tergite were classified as Aedes aegypti formosus (Aaf following the original description of the subspecies and the remainder were classified as Aedes aegypti aegypti (Aaa. There was a clear northwest-southeast cline in the abundance of Aaa and Aaf. Collections from the northern Sahelian region contained only Aaa while southern Forest gallery collections contained only Aaf. The two subspecies occurred in sympatry in four collections north of the Gambia in the central Savannah region and Aaa was a minor component of two collections from the Forest gallery area. Mosquitoes from 11 collections were orally challenged with DENV-2 virus. In agreement with the early literature, Aaf had significantly lower vector competence than Aaa. Among pure Aaa

  17. PETA RESISTENSI VEKTOR DEMAM BERDARAH DENGUE Aedes aegypti TERHADAP INSEKTISIDA KELOMPOK ORGANOFOSFAT, KARBAMAT DAN PYRETHROID DI PROPINSI JAWA TENGAH DAN DAERAH ISTIMEWA YOGYAKARTA

    OpenAIRE

    Widiarti Widiarti; Bambang Heriyanto; Damar Tri Boewono; Umi Widyastuti; Mujiono Mujiono; Lasmiati Lasmiati; Yuliadi Yuliadi

    2012-01-01

    Insecticide resistance study to DHF vector Aedes aegypti was carried out in Central Java and Yogyakarta Provinces. The objective of this study was to map the insecticide susceptibility of Aedes aegypti population to the three chemical groups of insecticide used in public health, in Central Java and Yogyakarta. Laboratory-reared, Fl generation of field population of Aedes aegypti from eleven and three Municipalities in Central Java and Yogyakarta Provinces were used respectively. T...

  18. Shifting patterns of Aedes aegypti fine scale spatial clustering in Iquitos, Peru.

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    Genevieve LaCon

    2014-08-01

    Full Text Available Empiric evidence shows that Aedes aegypti abundance is spatially heterogeneous and that some areas and larval habitats produce more mosquitoes than others. There is a knowledge gap, however, with regards to the temporal persistence of such Ae. aegypti abundance hotspots. In this study, we used a longitudinal entomologic dataset from the city of Iquitos, Peru, to (1 quantify the spatial clustering patterns of adult Ae. aegypti and pupae counts per house, (2 determine overlap between clusters, (3 quantify the temporal stability of clusters over nine entomologic surveys spaced four months apart, and (4 quantify the extent of clustering at the household and neighborhood levels.Data from 13,662 household entomological visits performed in two Iquitos neighborhoods differing in Ae. aegypti abundance and dengue virus transmission was analyzed using global and local spatial statistics. The location and extent of Ae. aegypti pupae and adult hotspots (i.e., small groups of houses with significantly [p<0.05] high mosquito abundance were calculated for each of the 9 entomologic surveys. The extent of clustering was used to quantify the probability of finding spatially correlated populations. Our analyses indicate that Ae. aegypti distribution was highly focal (most clusters do not extend beyond 30 meters and that hotspots of high vector abundance were common on every survey date, but they were temporally unstable over the period of study.Our findings have implications for understanding Ae. aegypti distribution and for the design of surveillance and control activities relying on household-level data. In settings like Iquitos, where there is a relatively low percentage of Ae. aegypti in permanent water-holding containers, identifying and targeting key premises will be significantly challenged by shifting hotspots of Ae. aegypti infestation. Focusing efforts in large geographic areas with historically high levels of transmission may be more effective than

  19. Vector competence in West African Aedes aegypti Is Flavivirus species and genotype dependent.

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    Laura B Dickson

    2014-10-01

    Full Text Available Vector competence of Aedes aegypti mosquitoes is a quantitative genetic trait that varies among geographic locations and among different flavivirus species and genotypes within species. The subspecies Ae. aegypti formosus, found mostly in sub-Saharan Africa, is considered to be refractory to both dengue (DENV and yellow fever viruses (YFV compared to the more globally distributed Ae. aegypti aegypti. Within Senegal, vector competence varies with collection site and DENV-2 viral isolate, but knowledge about the interaction of West African Ae. aegypti with different flaviviruses is lacking. The current study utilizes low passage isolates of dengue-2 (DENV-2-75505 sylvatic genotype and yellow fever (YFV BA-55 -West African Genotype I, or YFV DAK 1279-West African Genotype II from West Africa and field derived Ae. aegypti collected throughout Senegal to determine whether vector competence is flavivirus or virus genotype dependent.Eight collections of 20-30 mosquitoes from different sites were fed a bloodmeal containing either DENV-2 or either isolate of YFV. Midgut and disseminated infection phenotypes were determined 14 days post infection. Collections varied significantly in the rate and intensity of midgut and disseminated infection among the three viruses.Overall, vector competence was dependent upon both viral and vector strains. Importantly, contrary to previous studies, sylvatic collections of Ae. aegypti showed high levels of disseminated infection for local isolates of both DENV-2 and YFV.

  20. Mosquito larvicidal activity of aromatic medicinal plant oils against Aedes aegypti and Culex pipiens pallens.

    Science.gov (United States)

    Lee, Hoi-Seon

    2006-06-01

    Larvicidal activity of essential oils derived from 11 aromatic medicinal plants against early 4th-stage larvae of Aedes aegypti and Culex pipiens pallens was tested in the laboratory. At 100 ppm, the essential oils of all plants caused 100% mortality against Ae. aegypti and Cx. pipiens pallens. At 25 ppm, the essential oils of Citrus bergamia, Cuminum myrrha, and Pimenta racemosa caused 100% mortality against larvae of Ae. aegypti and Cx. pipiens pallens. The oil of C. begamia caused 32.5% and 24.5% mortality against Ae. aegypti and Cx. pipiens pallens at 12.5 ppm, but 24.2% and 0% mortality against Ae. aegypti and Cx. pipiens pallens at 6.25 ppm, respectively. The oil of P. racemosa caused 52.3% and 38.5% mortality against Ae. aegypti and Cx. pipiens pallens at 12.5 ppm, but 32.2% and 0% mortality against Ae. aegypti and Cx. pipiens pallens at 6.25 ppm, respectively. The larvicidal activity of oils of C. bergamia, C. myrrha, and P. racemosa was significantly reduced when used at 6.25 ppm. These plants warrant further studies as possible agents for mosquito control.

  1. Larvicidal and irritant activities of hexane leaf extracts of Citrus sinensis against dengue vector Aedes aegypti L.

    Institute of Scientific and Technical Information of China (English)

    Radhika Warikoo; Ankita Ray; Jasdeep Kaur Sandhu; Roopa Samal; Naim Wahab; Sarita Kumar

    2012-01-01

    Objective:To assess the larvicidal and irritant activities of the hexane extracts of leaves of Citrus sinensis (C. sinensis) against the early fourth instars and female adults of Aedes aegypti (Ae. aegypti). Methods: The larvicidal potential of the prepared leaf extract was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 h and LC50 and LC90 values were calculated. The efficacy of extract as mosquito irritant was assessed by contact irritancy assays. Extract-impregnated paper was placed on a glass plate over which a perspex funnel with a hole on the top was kept inverted. Single female adult, 3-day old unfed/blood-fed, was released inside the funnel. After 3 min of acclimatization time, the time taken for the first take-off and total number of flights undertaken during 15 min were scored. Results: The citrus leaf extracts from hexane possessed moderate larvicidal efficiency against dengue vector. The bioassays resulted in an LC50 and LC90 value of 446.84 and 1 370.96 ppm, respectively after 24 h of exposure. However, the extracts were proved to be remarkable irritant against adults Ae. aegypti, more pronounced effects being observed on blood-fed females than unfed females. The extract-impregnated paper was thus proved to be 7-11 times more irritable as compared with the control paper. Conclusions:The hexane extracts from C. sinensis leaves are proved to be reasonably larvicidal but remarkably irritant against dengue vector. Further studies are needed to identify the possible role of extract as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the extract could help in formulating strategies for mosquito control.

  2. Indirect effects of cigarette butt waste on the dengue vector Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Dieng, Hamady; Rajasaygar, Sudha; Ahmad, Abu Hassan; Rawi, Che Salmah Md; Ahmad, Hamdan; Satho, Tomomitsu; Miake, Fumio; Zuharah, Wan Fatma; Fukumitsu, Yuki; Saad, Ahmad Ramli; Abdul Hamid, Suhaila; Vargas, Ronald Enrique Morales; Ab Majid, Abdul Hafiz; Fadzly, Nik; Abu Kassim, Nur Faeza; Hashim, Nur Aida; Abd Ghani, Idris; Abang, Fatimah Bt; AbuBakar, Sazaly

    2014-02-01

    Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans.

  3. Indirect effects of cigarette butt waste on the dengue vector Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Dieng, Hamady; Rajasaygar, Sudha; Ahmad, Abu Hassan; Rawi, Che Salmah Md; Ahmad, Hamdan; Satho, Tomomitsu; Miake, Fumio; Zuharah, Wan Fatma; Fukumitsu, Yuki; Saad, Ahmad Ramli; Abdul Hamid, Suhaila; Vargas, Ronald Enrique Morales; Ab Majid, Abdul Hafiz; Fadzly, Nik; Abu Kassim, Nur Faeza; Hashim, Nur Aida; Abd Ghani, Idris; Abang, Fatimah Bt; AbuBakar, Sazaly

    2014-02-01

    Despite major insecticide-based vector control programs, dengue continues to be a major threat to public health in urban areas. The reasons for this failure include the emergence of insecticide resistance and the narrowing of the spectrum of efficient products. Cigarette butts (CBs), the most commonly discarded piece of waste, also represent a major health hazard to human and animal life. CBs are impregnated with thousands of chemical compounds, many of which are highly toxic and none of which has history of resistance in mosquitoes. This study was performed to examine whether exposure to CB alters various biological parameters of parents and their progeny. We examined whether the mosquito changes its ovipositional behaviors, egg hatching, reproductive capacity, longevity and fecundity in response to CB exposure at three different concentrations. Females tended to prefer microcosms containing CBs for egg deposition than those with water only. There were equivalent rates of eclosion success among larvae from eggs that matured in CB and water environments. We also observed decreased life span among adults that survived CB exposure. Extracts of CB waste have detrimental effects on the fecundity and longevity of its offspring, while being attractive to its gravid females. These results altogether indicate that CB waste indirectly affect key adult life traits of Aedes aegypti and could conceivably be developed as a novel dengue vector control strategy, referring to previously documented direct toxicity on the larval stage. But this will require further research on CB waste effects on non-target organisms including humans. PMID:24239749

  4. Insecticide susceptibility of Aedes aegypti populations from Senegal and Cape Verde Archipelago

    Directory of Open Access Journals (Sweden)

    Dia Ibrahima

    2012-10-01

    Full Text Available Abstract Background Two concomitant dengue 3 (DEN-3 epidemics occurred in Cape Verde Archipelago and Senegal between September and October 2009. Aedes aegypti was identified as the vector of these epidemics as several DEN-3 virus strains were isolated from this species in both countries. The susceptibility to pyrethroids, organochlorine, organophosphates and carbamate was investigated in two field strains of Aedes aegypti from both countries using WHO diagnostic bioassay kits in order to monitor their the current status of insecticide susceptibility. Findings The two tested strains were highly resistant to DDT. The Cape Verde strain was found to be susceptible to all others tested insecticides except for propoxur 0.1%, which needs further investigation. The Dakar strain was susceptible to fenitrothion 1% and permethrin 0.75%, but displayed reduced susceptibility to deltamethrin, lambda-cyhalothrin and propoxur. Conclusions As base-line results, our observations stress a careful management of insecticide use for the control of Ae. aegypti. Indeed, they indicate that DDT is no longer efficient for the control of Ae. aegypti populations in Cape Verde and Dakar and further suggest a thorough follow-up of propoxur susceptibility status in both sites and that of deltamethrin and lambda-cyhalothrin in Ae. aegypti populations in Dakar. Thus, regular monitoring of susceptibility is greatly needed as well as the knowing if this observed resistance/susceptibility is focal or not and for observed resistance, the use of biochemical methods is needed with detailed comparison of resistance levels over a large geographic area. Keywords Aedes aegypti, Insecticides, Susceptibility, Cape Verde, Senegal

  5. Screening for larvicidal activity of ethanolic and aqueous extracts of selected plants against Aedes aegypti and Aedes albopictus larvae

    Institute of Scientific and Technical Information of China (English)

    Michael RusselleAlvarez; Francisco Heralde III; Noel Quiming

    2016-01-01

    Objective: To screen for larvicidal activity of aqueous and ethanolic extracts (95% ethanol) from Selaginella elmeri, Christella dentata, Elatostema sinnatum, Curculigo capitulata, Euphorbia hirta, Murraya koenigii (M. koenigii), Alpinia speciosa, Cymbopogon citratus, Eucalyptus globulus (E. globulus), Jatropha curcas (J. curcas), Psidium guajava, Gliricidia sepium, Ixora coccinea and Capsicum frutescens (C. frutescens) against Aedes aegypti (A. aegypti) and Aedes albopictus (A. albopictus) 3rd instar larvae. Methods: Ethanolic and aqueous extracts were screened for larvicidal activity by exposing the A. aegypti and A. albopictus 3rd instar larvae (15 larvae per trial, triplicates) for 48 h, counting the mortalities every 24 h. Additionally, phytochemical screening for flavonoids, tannins, alkaloids, anthraquinones, anthrones, coumarins, indoles and steroids were performed on active extracts using spray tests. Results: Against A. aegypti, the three most active extracts were C. frutescens ethanolic (100%after 24 and 48 h), J. curcas ethanolic (84.44% after 24 h and 88.89% after 48 h) and M. koenigii ethanolic (53.33% after 24 h and 71.11% after 48 h). On the other hand, against A. albopictus, the three most active extracts were C. frutescens ethanolic (93.33% after 24 h and 100% after 48 h), J. curcas ethanolic (77.78% after 24 h and 82.22% after 48 h) and E. globulus ethanolic (64.44% after 24 h and 73.33% after 48 h). Phytochemical screening was also performed on the active extracts, revealing alkaloids, tannins, indoles and steroids. Conclusios: The results demonstrate the larvicidal activities of ethanolic extracts of Cymbopogon citratus, Euphorbia hirta, Ixora coccinea, Gliricidia sepium, M. koenigii, E. globulus, J. curcas and C. frutescens against A. aegypti and A. albopictus 3rd instar larvae. These could be used as potential larvicidal agents for the control of these mosquitoes.

  6. Insecticide resistance and its underlying mechanisms in field populations of Aedes aegypti adults (Diptera: Culicidae) in Singapore

    OpenAIRE

    Koou, Sin-Ying; Chong, Chee-Seng; Vythilingam, Indra; Lee, Chow-Yang; Ng, Lee-Ching

    2014-01-01

    Background In Singapore, dose–response bioassays of Aedes aegypti (L.) adults have been conducted, but the mechanisms underlying resistance to insecticides remain unclear. In this study, we evaluated insecticide resistance and its underlying mechanism in field populations of Ae. aegypti adults. Methods Seven populations of Ae. aegypti were collected from public residential areas and assays were conducted according to WHO guidelines to determine their susceptibility to several commonly used in...

  7. Susceptibility status of Aedes aegypti (L.) (Diptera: Culicidae) to temephos from three districts of Tamil Nadu, India

    OpenAIRE

    MUTHUSAMY, R; M S Shivakumar

    2015-01-01

    Background & objectives: Dengue is the most rapidly expanding arboviral disease in India. Aedes aegypti is the primary vector of dengue fever. Chemical insecticides have long been used in the vector control programmes along with other control measures. However, continuous use of insecticides targeting Ae. aegypti may lead to development of insecticide resistance. Though resistance in Ae. aegypti has been reported, the mutation in ace-1 gene associated with temephos resistance is not reported ...

  8. SUSCEPTIBILITY OF DENGUE HAEMORRHAGIC FEVER VECTOR (Aedes aegypti AGAINST ORGANOPHOSPHATE INSECTICIDES (MALATHION AND TEMEPHOS IN SOME DISTRICTS OF YOGYAKARTA AND CENTRAL JAVA PROVINCES

    Directory of Open Access Journals (Sweden)

    Damar Tri Boewono

    2012-11-01

    Full Text Available SUSCEPTIBILITY OF DENGUE HAEMORRHAGIC FEVER VECTOR (Aedes aegypti AGAINST ORGANOPHOSPHATE INSECTICIDES (MALATHION AND TEMEPHOS IN SOME DISTRICTS OF YOGYAKARTA AND CENTRAL JAVA PROVINCES

  9. History of domestication and spread of Aedes aegypti--a review.

    Science.gov (United States)

    Powell, Jeffrey R; Tabachnick, Walter J

    2013-01-01

    The adaptation of insect vectors of human diseases to breed in human habitats (domestication) is one of the most important phenomena in medical entomology. Considerable data are available on the vector mosquito Aedes aegypti in this regard and here we integrate the available information including genetics, behaviour, morphology, ecology and biogeography of the mosquito, with human history. We emphasise the tremendous amount of variation possessed by Ae. aegypti for virtually all traits considered. Typological thinking needs to be abandoned to reach a realistic and comprehensive understanding of this important vector of yellow fever, dengue and Chikungunya.

  10. Aedes aegypti susceptibility to insecticide from Abidjan City, Cote D'ivoire.

    Science.gov (United States)

    Konan, Lucien Yao; Coulibaly, Ibrahima Zanakoungo; Kone, Blaise Atioumounan; Ziogba, Jean-Claude Tokou; Diallo, Adama; Ekra, Daniel Kouadio; Traoré, Karim Sory; Doannio, Marie Christian Julien; Paul, Odehouri-Koudou

    2012-04-01

    The susceptibility of Aedes aegypti adults of three places in Abidjan city selected for an entomological surveillance of potential arbovirus vectors to permethrin, deltamethrin, lambdacyhalothrin, and propoxur was determined using WHO standard procedures. The wild populations of A. aegypti were susceptible to permethrin, deltamethirn, and lambdacyhalothin. Resistance to propoxur was detected in strains collected at the Autonomous Port of Abidjan and at Koumassi (mortality rate: 77%) but possibly resistance to this insecticide at the national zoological park (mortality rate: 90.8%). Populations of the national zoological park were possibly resistant to propoxur whereas those of the Autonomous port of Abidjan and of Koumassi were resistant.

  11. Methods for TALEN evaluation, use, and mutation detection in the mosquito Aedes aegypti

    Science.gov (United States)

    Basu, Sanjay; Aryan, Azadeh; Haac, Mary Etna; Myles, Kevin M.; Adelman, Zach N.

    2016-01-01

    The generation and study of transgenic Aedes aegypti mosquitoes provides an essential tool for elucidating the complex molecular biology of this important vector. Within the field, genetic manipulation has now surpassed the proof of principle stage and is now utilised in both applied and theoretical vector control strategies. The application of new instruments, technologies and techniques allows ever more controlled experiments to be conducted. In this text we describe microinjection of Ae. aegypti embryos in the context of evaluating and performing genomic editing with transcription activator-like effector nucleases (TALENs). PMID:26443221

  12. History of domestication and spread of Aedes aegypti--a review.

    Science.gov (United States)

    Powell, Jeffrey R; Tabachnick, Walter J

    2013-01-01

    The adaptation of insect vectors of human diseases to breed in human habitats (domestication) is one of the most important phenomena in medical entomology. Considerable data are available on the vector mosquito Aedes aegypti in this regard and here we integrate the available information including genetics, behaviour, morphology, ecology and biogeography of the mosquito, with human history. We emphasise the tremendous amount of variation possessed by Ae. aegypti for virtually all traits considered. Typological thinking needs to be abandoned to reach a realistic and comprehensive understanding of this important vector of yellow fever, dengue and Chikungunya. PMID:24473798

  13. Current resistance status to temephos in Aedes aegypti from different regions of Argentina

    Directory of Open Access Journals (Sweden)

    G Albrieu Llinás

    2010-02-01

    Full Text Available In Argentina, more than 25,000 cases of dengue were reported in the summer of 2009, even in provinces where the disease was formerly absent. We analysed the susceptibility levels to the larvicide temephos in seven populations of Aedes aegypti, the primary vector of dengue, collected during summer 2007/2008, using the susceptible Rockefeller strain as a control. Although no control failures were observed during the experiment, a majority of the lethal concentration and resistance ratio values indicate an incipient resistance. An integrative program to monitor the resistance of Ae. aegypti to insecticides is needed in the country.

  14. THE INSECT GROWTH REGULATOR, TRIFLUMURON (OMS-2015) AGAINST AEDES AEGYPTI IN JAKARTA, INDONESIA

    OpenAIRE

    M. Soekirno; Mathis, H. L.; Bang, Y. H.; Nunik St. Aminah

    2012-01-01

    Uji laboratorium dan lapangan dengan IGR Triflumuron (OMS-2015) terhadap larva nyamuk Aedes aegypti telah dilakukan di Jakarta. Uji laboratorium dilakukan dengan 6 variasi dosis, yaitu 0,004; 0,011; 0,034; 0,10; 0,33 dan 1,0 ppm Triflumuron terhadap perkembangan larva nyamuk Ae. aegypti di dalam tempayan. Dari uji laboratorium dapat diketahui bahwa Triflumuron dengan dosis 0,004 ppm dapat menekan perkembangan pupa untuk menjadi dewasa dalam waktu 2 minggu, sedangkan dosis 0,10 ppm menekan pad...

  15. Intermolecular interaction of thiosemicarbazone derivatives to solvents and a potential Aedes aegypti target

    Science.gov (United States)

    da Silva, João Bosco P.; Hallwass, Fernando; da Silva, Aluizio G.; Moreira, Diogo Rodrigo; Ramos, Mozart N.; Espíndola, José Wanderlan P.; de Oliveira, Ana Daura T.; Brondani, Dalci José; Leite, Ana Cristina L.; Merz, Kenneth M.

    2015-08-01

    DFT calculations were used to access information about structure, energy and electronic properties of series of phenyl- and phenoxymethyl-(thio)semicarbazone derivatives with demonstrated activity against the larvae of Aedes aegypti in stage L4. The way as the thiosemicarbazone derivatives can interact with solvents like DMSO and water were analyzed from the comparison between calculated and experimental 1H NMR chemical shifts. The evidences of thiosemicarbazone derivatives making H-bond interaction to solvent have provide us insights on how they can interact with a potential A. aegypti's biological target, the Sterol Carrier Protein-2.

  16. Field validation of a transcriptional assay for the prediction of age of uncaged Aedes aegypti mosquitoes in Northern Australia.

    Directory of Open Access Journals (Sweden)

    Leon E Hugo

    Full Text Available BACKGROUND: New strategies to eliminate dengue have been proposed that specifically target older Aedes aegypti mosquitoes, the proportion of the vector population that is potentially capable of transmitting dengue viruses. Evaluation of these strategies will require accurate and high-throughput methods of predicting mosquito age. We previously developed an age prediction assay for individual Ae. aegypti females based on the transcriptional profiles of a selection of age responsive genes. Here we conducted field testing of the method on Ae. aegypti that were entirely uncaged and free to engage in natural behavior. METHODOLOGY/PRINCIPAL FINDINGS: We produced "free-range" test specimens by releasing 8007 adult Ae. aegypti inside and around an isolated homestead in north Queensland, Australia, and recapturing females at two day intervals. We applied a TaqMan probe-based assay design that enabled high-throughput quantitative RT-PCR of four transcripts from three age-responsive genes and a reference gene. An age prediction model was calibrated on mosquitoes maintained in small sentinel cages, in which 68.8% of the variance in gene transcription measures was explained by age. The model was then used to predict the ages of the free-range females. The relationship between the predicted and actual ages achieved an R(2 value of 0.62 for predictions of females up to 29 days old. Transcriptional profiles and age predictions were not affected by physiological variation associated with the blood feeding/egg development cycle and we show that the age grading method could be applied to differentiate between two populations of mosquitoes having a two-fold difference in mean life expectancy. CONCLUSIONS/SIGNIFICANCE: The transcriptional profiles of age responsive genes facilitated age estimates of near-wild Ae. aegypti females. Our age prediction assay for Ae. aegypti provides a useful tool for the evaluation of mosquito control interventions against dengue where

  17. Antiviral Hammerhead Ribozymes Are Effective for Developing Transgenic Suppression of Chikungunya Virus in Aedes aegypti Mosquitoes.

    Science.gov (United States)

    Mishra, Priya; Furey, Colleen; Balaraman, Velmurugan; Fraser, Malcolm J

    2016-01-01

    The chikungunya virus (CHIKV) is an emerging pathogen with widespread distribution in regions of Africa, India, and Asia that threatens to spread into temperate climates with the introduction of its major vector, Aedes albopictus. CHIKV causes a disease frequently misdiagnosed as dengue fever, with potentially life-threatening symptoms that can result in a longer-term debilitating arthritis. The increasing risk of spread from endemic regions via human travel and commerce and the current absence of a vaccine put a significant proportion of the world population at risk for this disease. In this study we designed and tested hammerhead ribozymes (hRzs) targeting CHIKV structural protein genes of the RNA genome as potential antivirals both at the cellular and in vivo level. We employed the CHIKV strain 181/25, which exhibits similar infectivity rates in both Vero cell cultures and mosquitoes. Virus suppression assay performed on transformed Vero cell clones of all seven hRzs demonstrated that all are effective at inhibiting CHIKV in Vero cells, with hRz #9 and #14 being the most effective. piggyBac transformation vectors were constructed using the Ae. aegypti t-RNA(val) Pol III promoted hRz #9 and #14 effector genes to establish a total of nine unique transgenic Higgs White Eye (HWE) Ae. aegypti lines. Following confirmation of transgene expression by real-time polymerase chain reaction (RT-PCR), comparative TCID50-IFA analysis, in situ Immuno-fluorescent Assays (IFA) and analysis of salivary CHIKV titers demonstrated effective suppression of virus replication at 7 dpi in heterozygous females of each of these transgenic lines compared with control HWE mosquitoes. This report provides a proof that appropriately engineered hRzs are powerful antiviral effector genes suitable for population replacement strategies. PMID:27294950

  18. Development of a mosquito attractant blend of small molecules against host-seeking Aedes aegypti.

    Science.gov (United States)

    Saratha, R; Mathew, Nisha

    2016-04-01

    A mosquito's dependence on olfaction in the hunt for human host could be efficiently exploited to protect humans from mosquito bites. The present study is undertaken to make the most attractant compound blend for Aedes aegypti mosquitoes to lure them to traps. Eleven molecules (M1-M11) at different dilutions were screened for attractancy against non-blood-fed adult female mosquitoes in an olfactometer. The results showed that the attractancy was dependent on both the chemical nature of the molecule and the strength of the odor. Out of 11 molecules screened, 9 showed significant attractancy (P  M7 > M6 > M10 > M9 > M3 > M2 > M1 > M4 with attractancy indices (AIs) 86.11, 55.93, 55.17, 54, 52.94, 52, 50, 43.64, and 32, respectively, at the optimum dilutions. Seven blends (I-VII) were made and were screened for attractancy against Ae. aegypti. All the blends showed significant attractancy (P  III > IV > I > VI > V > II with AIs 96.63, 89.19, 65, 57.89, 56.1, 47.13, and 44.44, respectively. Among the seven blends, blend VII with constituent molecules M6, M9, M10, and M11 is the most promising with an AI value of 96.63. This blend will be useful in luring the host-seeking mosquitoes to traps. The field efficacy of these attractant blends may be explored in the future. PMID:26693718

  19. Antiviral Hammerhead Ribozymes Are Effective for Developing Transgenic Suppression of Chikungunya Virus in Aedes aegypti Mosquitoes

    Directory of Open Access Journals (Sweden)

    Priya Mishra

    2016-06-01

    Full Text Available The chikungunya virus (CHIKV is an emerging pathogen with widespread distribution in regions of Africa, India, and Asia that threatens to spread into temperate climates with the introduction of its major vector, Aedes albopictus. CHIKV causes a disease frequently misdiagnosed as dengue fever, with potentially life-threatening symptoms that can result in a longer-term debilitating arthritis. The increasing risk of spread from endemic regions via human travel and commerce and the current absence of a vaccine put a significant proportion of the world population at risk for this disease. In this study we designed and tested hammerhead ribozymes (hRzs targeting CHIKV structural protein genes of the RNA genome as potential antivirals both at the cellular and in vivo level. We employed the CHIKV strain 181/25, which exhibits similar infectivity rates in both Vero cell cultures and mosquitoes. Virus suppression assay performed on transformed Vero cell clones of all seven hRzs demonstrated that all are effective at inhibiting CHIKV in Vero cells, with hRz #9 and #14 being the most effective. piggyBac transformation vectors were constructed using the Ae. aegypti t-RNAval Pol III promoted hRz #9 and #14 effector genes to establish a total of nine unique transgenic Higgs White Eye (HWE Ae. aegypti lines. Following confirmation of transgene expression by real-time polymerase chain reaction (RT-PCR, comparative TCID50-IFA analysis, in situ Immuno-fluorescent Assays (IFA and analysis of salivary CHIKV titers demonstrated effective suppression of virus replication at 7 dpi in heterozygous females of each of these transgenic lines compared with control HWE mosquitoes. This report provides a proof that appropriately engineered hRzs are powerful antiviral effector genes suitable for population replacement strategies

  20. PENGARUH FREKUENSI PENGHISAPAN DARAH TERHADAP PERKEMBANGAN, REPRODUKSI,VERTILITAS DAN RASIO SEX Aedes aegypti

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    Riyani Setiyaningsih

    2014-06-01

    Full Text Available Aedes aegypti is a vector of Dengue hemorrhagic fever in Indonesia. Aedesaegypti has a high reproduction ability. Each individual can produce 50-100 eggs. Which80% of them are fertile. The mosquito is multiple biting (which means each individualsucks blood several time. Based on that background, this research was aimed torecognize the frequency of blood sucking to development, reproduction, fertility, and sexratio of Ae. aegypti. Thirty Ae. aegypti mosquito were put into the plastic cupsindividually, then fed with mammals. The treatments were the first, second, third, fourth,and fifth blood sucking. The eggs produced in each blood sucking were hatched andmaintain to become mosquitoes. The parameter measured from each blood sucking istotal egg production, egg fertility, larvae mortality, pupae mortality, and sex ratio. Theresult of the research shows that the frequency of blood sucking affects the production ofegg fertility, but does not affect the total egg production, larvae mortality, pupaemortality, and sex ratio significantly.Key words: sex ratio, egg fertility, reproduction Aedes aegypti adalah vektor Demam berdarah dengue di Indonesia. Ae aegyptimempunyai kemampuan berkembang biak dengan cepat. Setiap individu mempunyaikemampuan menghasilkan telur 50 sampai 100 ekor skali bertclur. Ae. aegypti bersifat multibiting, masing-masing individu mempunyai kemampuan menghisap darah beberapa kali dalamkurun waktu tertentu. Berdasarkan latar belakang tersebut tujuan penelitian ini adalahmendapatkan pengaruh frekuensi penghisapan darah terhadap perkembangan reproduksi,fcrtilitas, dan rasio sex dari Ae. aegypti. Ae aegypti dimasukkan ke dalam cup plastik secaraindividual, kemudian diberikan darah mamalia selama kurang lebih 3 menit. Pemberian darahdilakukan secara bertahap yaitu pemberian darah pertama, kedua, ketiga, ke empat, dan ke limaTelur-telur yang dihasilkan pada masing-masing penghisapan darah di tetaskan dan dipeliharasampai menjadi nyamuk

  1. Comparative mosquito repellency of essential oils against Aedes aegypti (Linn.), Anopheles dirus (Peyton and Harrison) and Culex quinquefasciatus (Say)

    Institute of Scientific and Technical Information of China (English)

    Siriporn Phasomkusolsil; Mayura Soonwera

    2011-01-01

    Objective: To assess the repellency to female Aedes aegypti (Ae. aegypti), Anopheles dirus (An. dirus) and Culex quinquefasciatus (Cx. quinquefasciatus) of seven essential oils using two treatment methods. Methods: Topical applications of three dose concentrations (0.02, 0.10 and 0.21 mg/cm2) were made on the forearms of volunteers. Dose-response study and protection time study were employed in the experiment. Results: In the dose-response test, Cymbopogon citratus (C. citratus), Cymbopogon nardus (C. nardus), Syzygium aromaticum (S. aromaticum) and Ocimum basilicum (O. basilicum) exhibited a high repellency against Ae. aegypti with ED50 at < 0.045 mg/cm2, whereas C. citratus, C. nardus and S. aromaticum showed repellency against An. dirus with ED50 at <0.068 mg/cm2. Furthermore, the essential oils of C. citratus, C. nardus, S. aromaticum, O.basilicum and Cananga odorata gave strong effective dose (ED 50) values at <0.003 mg/cm2 when tested against Cx. quinquefasciatus. For testing by arm in cage method, at 0.21 mg/cm2, protection time of C. citratus gave the longest lasting period against three mosquito species, 72 min for Ae. aegypti, 132 min for An. dirus and 84 min for Cx. quinquefasciatus. In addition, the two essential oils exhibited moderate repellency against Ae. aegypti, An. dirus and Cx. quinquefasciatus, at 60, 90 and 78 min with C. nardus, and 54, 96 and 72 min with S. aromaticum, respectively. Conclusions: The percentage repellency increased when the concentration of essential oils increased. In contrast, biting rates decreased when the concentration of essential oils increased.C. citratus exhibited high efficiency for the protection time and the percentage of biting deterrent against all of 3 mosquito species.

  2. Vectorial capacity of Aedes aegypti for dengue virus type 2 is reduced with co-infection of Metarhizium anisopliae.

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    Javier A Garza-Hernández

    Full Text Available BACKGROUND: Aedes aegypti, is the major dengue vector and a worldwide public health threat combated basically by chemical insecticides. In this study, the vectorial competence of Ae. aegypti co-infected with a mildly virulent Metarhizium anisopliae and fed with blood infected with the DENV-2 virus, was examined. METHODOLOGY/PRINCIPAL FINDINGS: The study encompassed three bioassays (B. In B1 the median lethal time (LT50 of Ae. aegypti exposed to M. anisopliae was determined in four treatments: co-infected (CI, single-fungus infection (SF, single-virus infection (SV and control (C. In B2, the mortality and viral infection rate in midgut and in head were registered in fifty females of CI and in SV. In B3, the same treatments as in B1 but with females separated individually were tested to evaluate the effect on fecundity and gonotrophic cycle length. Survival in CI and SF females was 70% shorter than the one of those in SV and control. Overall viral infection rate in CI and SV were 76 and 84% but the mortality at day six post-infection was 78% (54% infected and 6% respectively. Survivors with virus in head at day seven post-infection were 12 and 64% in both CI and SV mosquitoes. Fecundity and gonotrophic cycle length were reduced in 52 and 40% in CI compared to the ones in control. CONCLUSION/SIGNIFICANCE: Fungus-induced mortality for the CI group was 78%. Of the survivors, 12% (6/50 could potentially transmit DENV-2, as opposed to 64% (32/50 of the SV group, meaning a 5-fold reduction in the number of infective mosquitoes. This is the first report on a fungus that reduces the vectorial capacity of Ae. aegypti infected with the DENV-2 virus.

  3. Biogeography of the two major arbovirus mosquito vectors, Aedes aegypti and Aedes albopictus (Diptera, Culicidae, in Madagascar

    Directory of Open Access Journals (Sweden)

    Raharimalala Fara

    2012-03-01

    Full Text Available Abstract Background In the past ten years, the Indian Ocean region has been the theatre of severe epidemics of chikungunya and dengue. These outbreaks coincided with a high increase in populations of Aedes albopictus that outcompete its sister taxon Aedes aegypti in most islands sampled. The objective of this work was to update the entomological survey of the two Aedes species in the island of Madagascar which has to face these arboviroses. Methods The sampling of Aedes mosquitoes was conducted during two years, from October 2007 to October 2009, in fifteen localities from eight regions of contrasting climates. Captured adults were identified immediately whereas immature stages were bred until adult stage for determination. Phylogenetic analysis was performed using two mtDNA genes, COI and ND5 and trees were constructed by the maximum likelihood (ML method with the gene time reversible (GTR model. Experimental infections with the chikungunya virus strain 06.21 at a titer of 107.5 pfu/mL were performed to evaluate the vector competence of field-collected mosquitoes. Disseminated infection rates were measured fourteen days after infection by immunofluorescence assay performed on head squashes. Results The species Aedes aegypti was detected in only six sites in native forests and natural reserves. In contrast, the species Aedes albopictus was found in 13 out of the 15 sites sampled. Breeding sites were mostly found in man-made environments such as discarded containers, used tires, abandoned buckets, coconuts, and bamboo cuts. Linear regression models showed that the abundance of Ae. albopictus was significantly influenced by the sampling region (F = 62.00, p -16 and period (F = 36.22, p = 2.548 × 10-13, that are associated with ecological and climate variations. Phylogenetic analysis of the invasive Ae. albopictus distinguished haplotypes from South Asia and South America from those of Madagascar, but the markers used were not discriminant enough

  4. Insecticidal and repellent activity of Siparuna guianensis Aubl. (Negramina) against Aedes aegypti and Culex quinquefasciatus.

    Science.gov (United States)

    Aguiar, Raimundo Wagner Souza; dos Santos, Suetonio Fernandes; da Silva Morgado, Fabricio; Ascencio, Sergio Donizeti; de Mendonça Lopes, Magnólia; Viana, Kelvinson Fernandes; Didonet, Julcemar; Ribeiro, Bergmann Morais

    2015-01-01

    This study investigated the toxic effects of essential oils isolated from Siparuna guianensis against Aedes aegypti, Culex quinquefasciatus (eggs, larvae, pupae, and adult) and Aedes albopictus (C6/36) cells. The oviposition-deterring activity, egg viability, and repellence activity in the presence of different essential oils concentrations were determined. The essential oils showed high toxicity to all developmental stages of A. aegypti and C. quinquefasciatus. Furthermore, the oils also showed high repellent activity towards the adult stage of mosquitoes (0.025 to 0.550 μg/cm2 skin conferred 100% repellence up to 120 min) and in contact with cultured insect cells (C6/36) induced death possibly by necrosis. The results presented in this work show the potential of S. guianensis essential oils for the development of an alternative and effective method for the natural control of mosquitoes in homes and urban areas.

  5. Wolbachia Blocks Currently Circulating Zika Virus Isolates in Brazilian Aedes aegypti Mosquitoes.

    Science.gov (United States)

    Dutra, Heverton Leandro Carneiro; Rocha, Marcele Neves; Dias, Fernando Braga Stehling; Mansur, Simone Brutman; Caragata, Eric Pearce; Moreira, Luciano Andrade

    2016-06-01

    The recent association of Zika virus with cases of microcephaly has sparked a global health crisis and highlighted the need for mechanisms to combat the Zika vector, Aedes aegypti mosquitoes. Wolbachia pipientis, a bacterial endosymbiont of insect, has recently garnered attention as a mechanism for arbovirus control. Here we report that Aedes aegypti harboring Wolbachia are highly resistant to infection with two currently circulating Zika virus isolates from the recent Brazilian epidemic. Wolbachia-harboring mosquitoes displayed lower viral prevalence and intensity and decreased disseminated infection and, critically, did not carry infectious virus in the saliva, suggesting that viral transmission was blocked. Our data indicate that the use of Wolbachia-harboring mosquitoes could represent an effective mechanism to reduce Zika virus transmission and should be included as part of Zika control strategies. PMID:27156023

  6. A Multipurpose, High-Throughput Single-Nucleotide Polymorphism Chip for the Dengue and Yellow Fever Mosquito, Aedes aegypti.

    Science.gov (United States)

    Evans, Benjamin R; Gloria-Soria, Andrea; Hou, Lin; McBride, Carolyn; Bonizzoni, Mariangela; Zhao, Hongyu; Powell, Jeffrey R

    2015-05-01

    The dengue and yellow fever mosquito, Aedes aegypti, contributes significantly to global disease burden. Genetic study of Aedes aegypti is essential to understanding its evolutionary history, competence as a disease vector, and the effects and efficacy of vector control methods. The prevalence of repeats and transposable elements in the Aedes aegypti genome complicates marker development and makes genome-wide genetic study challenging. To overcome these challenges, we developed a high-throughput genotyping chip, Axiom_aegypti1. This chip screens for 50,000 single-nucleotide polymorphisms present in Aedes aegypti populations from around the world. The array currently used genotypes 96 samples simultaneously. To ensure that these markers satisfy assumptions commonly made in many genetic analyses, we tested for Mendelian inheritance and linkage disequilibrium in laboratory crosses and a wild population, respectively. We have validated more than 25,000 of these markers to date, and expect this number to increase with more sampling. We also present evidence of the chip's efficacy in distinguishing populations throughout the world. The markers on this chip are ideal for applications ranging from population genetics to genome-wide association studies. This tool makes rapid, cost-effective, and comparable genotype data attainable to diverse sets of Aedes aegypti researchers, from those interested in potential range shifts due to climate change to those characterizing the genetic underpinnings of its competence to transmit disease. PMID:25721127

  7. THE INSECT GROWTH REGULATOR, TRIFLUMURON (OMS-2015 AGAINST AEDES AEGYPTI IN JAKARTA, INDONESIA

    Directory of Open Access Journals (Sweden)

    M. Soekirno

    2012-09-01

    Full Text Available Uji laboratorium dan lapangan dengan IGR Triflumuron (OMS-2015 terhadap larva nyamuk Aedes aegypti telah dilakukan di Jakarta. Uji laboratorium dilakukan dengan 6 variasi dosis, yaitu 0,004; 0,011; 0,034; 0,10; 0,33 dan 1,0 ppm Triflumuron terhadap perkembangan larva nyamuk Ae. aegypti di dalam tempayan. Dari uji laboratorium dapat diketahui bahwa Triflumuron dengan dosis 0,004 ppm dapat menekan perkembangan pupa untuk menjadi dewasa dalam waktu 2 minggu, sedangkan dosis 0,10 ppm menekan padat populasi nyamuk Ae. aegypti selama 4 minggu dan dosis 1,0 ppm menekan padat populasi nyamuk Ae. aegypti selama 8 minggu. Uji lapangan dengan menggunakan Triflumuron di daerah pelabuhan Tanjung Priok, Jakarta, seluas 27 hektar dengan dua kali perlakuan, dengan dosis 0,042 dan 0,075 ppm, terjadi penurunan populasi nyamuk Ae. aegypti dewasa dan indeks pupa menjadi 0 dalam 4 hari setelah perlakuan. Penurunan populasi nyamuk Ae. aegypti dewasa terlihat setelah 2 minggu se­sudah perlakuan dengan tidak berhasilnya larva/pupa menjadi nyamuk dewasa. 

  8. Stability of the wMel Wolbachia Infection following invasion into Aedes aegypti populations.

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    Ary A Hoffmann

    2014-09-01

    Full Text Available The wMel infection of Drosophila melanogaster was successfully transferred into Aedes aegypti mosquitoes where it has the potential to suppress dengue and other arboviruses. The infection was subsequently spread into two natural populations at Yorkeys Knob and Gordonvale near Cairns, Queensland in 2011. Here we report on the stability of the infection following introduction and we characterize factors influencing the ongoing dynamics of the infection in these two populations. While the Wolbachia infection always remained high and near fixation in both locations, there was a persistent low frequency of uninfected mosquitoes. These uninfected mosquitoes showed weak spatial structure at both release sites although there was some clustering around two areas in Gordonvale. Infected females from both locations showed perfect maternal transmission consistent with patterns previously established pre-release in laboratory tests. After >2 years under field conditions, the infection continued to show complete cytoplasmic incompatibility across multiple gonotrophic cycles but persistent deleterious fitness effects, suggesting that host effects were stable over time. These results point to the stability of Wolbachia infections and their impact on hosts following local invasion, and also highlight the continued persistence of uninfected individuals at a low frequency most likely due to immigration.

  9. Wolbachia infection reduces blood-feeding success in the dengue fever mosquito, Aedes aegypti.

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    Andrew P Turley

    Full Text Available BACKGROUND: The mosquito Aedes aegypti was recently transinfected with a life-shortening strain of the endosymbiont Wolbachia pipientis (wMelPop as the first step in developing a biocontrol strategy for dengue virus transmission. In addition to life-shortening, the wMelPop-infected mosquitoes also exhibit increased daytime activity and metabolic rates. Here we sought to quantify the blood-feeding behaviour of Wolbachia-infected females as an indicator of any virulence or energetic drain associated with Wolbachia infection. METHODOLOGY/PRINCIPAL FINDINGS: In a series of blood-feeding trials in response to humans, we have shown that Wolbachia-infected mosquitoes do not differ in their response time to humans, but that as they age they obtain fewer and smaller blood meals than Wolbachia-uninfected controls. Lastly, we observed a behavioural characteristic in the Wolbachia infected mosquitoes best described as a "bendy" proboscis that may explain the decreased biting success. CONCLUSIONS/SIGNIFICANCE: Taken together the evidence suggests that wMelPop infection may be causing tissue damage in a manner that intensifies with mosquito age and that leads to reduced blood-feeding success. These behavioural changes require further investigation with respect to a possible physiological mechanism and their role in vectorial capacity of the insect. The selective decrease of feeding success in older mosquitoes may act synergistically with other Wolbachia-associated traits including life-shortening and viral protection in biocontrol strategies.

  10. Evaluation of methoprene effect on Aedes aegypti (Diptera: Culicidae development in laboratory conditions

    Directory of Open Access Journals (Sweden)

    Ima Aparecida Braga

    2005-07-01

    Full Text Available Several Brazilian Aedes aegypti populations are resistant to the larvicidae temephos. Methoprene, that inhibits adult emergence, is one of the alternatives envisaged by the Brazilian Dengue Control Program (PNCD. However, at Brazil vector infestation rates are measured through larvae indexes and it has been claimed that methoprene use in the field could face operational problems. In order to define a standardized protocol, methoprene effect was evaluated in laboratory conditions after continuous exposure of larvae (Rockefeller strain to a methoprene formulation available to the PNCD. Methoprene-derived mortality occurs mainly at the pupa stage and pupa development is inversely proportional to methoprene concentration. Number and viability of eggs laid by treated and control females are equivalent. A methoprene dose-dependent delay in the development was noted; however, b correlations were found for total mortality or adult emergence inhibition if data obtained when all control mosquitoes have emerged are compared to data obtained when methoprene-treated groups finish development. The cumulative record of total methoprene-induced mortality at the time control adults emerge is proposed for routine evaluation of field populations. Mortality of all specimens, but not of larva, could account for adult emergence inhibition, confirming the inadequacy of larvae indexes to evaluate methoprene effect.

  11. Further insecticidal activities of essential oils from Lippia sidoides and Croton species against Aedes aegypti L.

    Science.gov (United States)

    de Lima, Glauber Pacelli Gomes; de Souza, Terezinha Maria; de Paula Freire, Gabrielle; Farias, Davi Felipe; Cunha, Arcelina Pacheco; Ricardo, Nágila Maria Pontes Silva; de Morais, Selene Maia; Carvalho, Ana Fontenele Urano

    2013-05-01

    This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg mL(-1), larvicidal activity with LC50 ranging from 25.5 to 94.6 μg mL(-1), and pupicidal action with PC50 ranging from 276.8 to over 500 μg mL(-1). Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg mL(-1), respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50 > 6,000 mg.kg(-1)) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg(-1), respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals. PMID:23435925

  12. Natural vertical transmission of dengue viruses in Aedes aegypti in selected sites in Cebu City, Philippines.

    Science.gov (United States)

    Edillo, Frances E; Sarcos, Janet R; Sayson, Stephanie L

    2015-12-01

    We attempted to determine the vertical transmission of dengue virus (DENV) in Aedes aegypti in selected sites in Cebu City, Philippines. Mosquito sub-adults were collected monthly from households and the field during the wet-dry-wet season from November, 2011 to July, 2012 and were laboratory-reared to adults. Viral RNA extracts in mosquitoes were assayed by hemi-nested RT-PCR. Results showed that 62 (36.26%; n=679) out of 171 mosquito pools (n=2,871) were DENV+. The minimum infection rate (MIR) of DENV ranged from 0 in wet months to 48.22/1,000 mosquitoes in April, 2012 (mid-dry). DENVs were detected in larvae, pupae, and male and female adults, with DENV-4, DENV-3, and DENV-1, in that rank of prevalence. DENV-1 co-infected with either DENV-3 or -4 or with both in April, 2012; DENV-3 and -4 were present in both seasons. More DENV+ mosquitoes were collected from households than in field premises (p0.05). By Generalized Linear Mixed models, the type of premises nested in sites and monthly total rainfall were significant predictors of monthly dengue cases (pdengue outbreak.

  13. Further insecticidal activities of essential oils from Lippia sidoides and Croton species against Aedes aegypti L.

    Science.gov (United States)

    de Lima, Glauber Pacelli Gomes; de Souza, Terezinha Maria; de Paula Freire, Gabrielle; Farias, Davi Felipe; Cunha, Arcelina Pacheco; Ricardo, Nágila Maria Pontes Silva; de Morais, Selene Maia; Carvalho, Ana Fontenele Urano

    2013-05-01

    This study assessed new insecticidal activities of essential oils from Lippia sidoides and Croton species (Croton zehntneri, Croton nepetaefolius, Croton argyrophylloides, and Croton sonderianus) against Aedes aegypti mosquito. In addition, the acute toxicity upon mice was determined. All essential oils showed inhibition of egg hatching, with IC50 values ranging from 66.4 to 143.2 μg mL(-1), larvicidal activity with LC50 ranging from 25.5 to 94.6 μg mL(-1), and pupicidal action with PC50 ranging from 276.8 to over 500 μg mL(-1). Only L. sidoides, C. zehntneri, and C. argyrophylloides essential oils were able to inhibit the oviposition of female gravid mosquitoes with OD50 values of 35.3, 45.3, and 45.8 μg mL(-1), respectively. Oral acute toxicity in mice showed that C. sonderianus and C. argyrophylloides oils are nontoxic (LD50 > 6,000 mg.kg(-1)) while C. nepetaefolius, C. zehntneri, and L. sidoides oils are moderately toxic (LD50 3,840; 3,464, and 2,624 mg.kg(-1), respectively). The results indicate that these oils are promising sources of bioactive compounds, showing low or no toxicity to mammals.

  14. Effects of Croton rhamnifolioides essential oil on Aedes aegypti oviposition, larval toxicity and trypsin activity.

    Science.gov (United States)

    Santos, Geanne K N; Dutra, Kamilla A; Lira, Camila S; Lima, Bheatriz N; Napoleão, Thiago H; Paiva, Patrícia M G; Maranhão, Claudia A; Brandão, Sofia S F; Navarro, Daniela M A F

    2014-01-01

    Although numerous reports are available concerning the larvicidal potential of essential oils, very few investigations have focused on their mechanisms of action. In the present study, we have investigated the chemical composition of the leaf oil of Croton rhamnifolioides during storage and its effects on oviposition and survival of larvae of the dengue fever mosquito Aedes aegypti. In addition, we have established a possible mechanism of action for the larvicidal activity of the essential oil. GC-MS analyses revealed marked differences in the composition of oil that had been freshly isolated and that of a sample that had been stored in a sealed amber-glass vial under refrigeration for three years. However, both fresh and stored oil exhibited substantial larvicidal activities with LC50 values of 122.35 and 89.03 ppm, respectively, and oviposition deterrent effects against gravid females at concentrations of 50 and 100 µg·mL-1. These results demonstrate that the larvicidal effect of the essential oil was unchanged during three years of storage even though its chemical composition altered. Hence, the essential oil could be used in the preparation of commercial products. In addition, we observed that the trypsin-like activity of mosquito larvae was inhibited in vitro by the essential oil of C. rhamnifolioides, suggesting that the larvicidal effect may be associated with inhibition of this enzyme.

  15. Large diurnal temperature fluctuations negatively influence Aedes aegypti (Diptera: Culicidae) life-history traits.

    Science.gov (United States)

    Carrington, Lauren B; Seifert, Stephanie N; Willits, Neil H; Lambrechts, Louis; Scott, Thomas W

    2013-01-01

    Seasonal variation in dengue virus transmission in northwestern Thailand is inversely related to the magnitude of diurnal temperature fluctuations, although mean temperature does not vary significantly across seasons. We tested the hypothesis that diurnal temperature fluctuations negatively influence epidemiologically important life-history traits of the primary dengue vector, Aedes aegypti (L.), compared with a constant 26 degrees C temperature. A large diurnal temperature range (DTR) (approximately equals 18 degrees C daily swing) extended immature development time (>1 d), lowered larval survival (approximately equals 6%), and reduced adult female reproductive output by 25% 14 d after blood feeding, relative to the constant 26 degreesC temperature. A small DTR (approximately equal 8 degrees C daily swing) led to a negligible or slightly positive effect on the life history traits tested. Our results indicate that there is a negative impact of large DTR on mosquito biology and are consistent with the hypothesis that, in at least some locations, large temperature fluctuations contribute to seasonal reduction in dengue virus transmission. PMID:23427651

  16. The wMel strain of Wolbachia Reduces Transmission of Zika virus by Aedes aegypti

    OpenAIRE

    Aliota, Matthew T; Peinado, Stephen A.; Ivan Dario Velez; Jorge E Osorio

    2016-01-01

    Zika virus (ZIKV) is causing an explosive outbreak of febrile disease in the Americas. There are no effective antiviral therapies or licensed vaccines for this virus, and mosquito control strategies have not been adequate to contain the virus. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however...

  17. Rotenoids from Tephrosia toxicaria with larvicidal activity against Aedes aegypti, the main vector of dengue fever

    International Nuclear Information System (INIS)

    In the search for new larvicides from plants, we have investigated the potential activity of the rotenoids deguelin (1), 12a-hydroxy-a-toxicarol (2) and tephrosin (3), isolated from the bioactive ethanol extract of roots of Tephrosia toxicaria Pers., against Aedes aegypti, the main vector of dengue. The absolute configuration of these compounds was determined by circular dichroism (CD) spectra. The LC50 values of the compounds evaluated justify the potential of T. toxicaria as a new natural larvicide. (author)

  18. Water Level Flux in Household Containers in Vietnam - A Key Determinant of Aedes aegypti Population Dynamics

    OpenAIRE

    Jeffery, Jason A. L.; Archie C.A. Clements; Yen Thi Nguyen; Le Hoang Nguyen; Son Hai Tran; Nghia Trung Le; Nam Sinh Vu; Ryan, Peter A; Kay, Brian H.

    2012-01-01

    We examined changes in the abundance of immature Aedes aegypti at the household and water storage container level during the dry-season (June-July, 2008) in Tri Nguyen village, central Vietnam. We conducted quantitative immature mosquito surveys of 171 containers in the same 41 households, with replacement of samples, every two days during a 29-day period. We developed multi-level mixed effects regression models to investigate container and household variability in pupal abundance. The percen...

  19. DAMPAK FOGGING INSEKTISIDA MALATHION, FENDONA, CYNOFF DAN ICON TERHADAP ANGKA JENTIK NYAMUK Aedes aegypti

    OpenAIRE

    M. Hasyimi; Mardjan Soekirno; Amrul Munif; Anwar Musadad

    2012-01-01

    Insektisida malathion, fendona, cynoff dan icon adalah jenis insektisida yang sasarannya adalah nyamuk Aedes aegypti dewasa. Jumlah kematian nyamuk dewasa akan berdampak terhadap angka jentik. Penelitian lapangan berskala kecil untuk mengetahui dampaknya terhadap angka jentik yang terdiri Container index (CI), House index (HI) dan Breteau index (BI) telah dilakukan pada bulan Juni 2004. Penelitian dilakukan di Kelurahan Kramatjati Jakarta Timur pada RW yang berbeda-beda.Pengambilan data angka...

  20. Identification and characterization of juvenile hormone esterase gene from the yellow fever mosquito, Aedes aegypti

    OpenAIRE

    Bai, Hua; Ramaseshadri, Parthasarathy; Palli, Subba Reddy

    2007-01-01

    Juvenile hormone esterase (JHE) plays an important role in regulating juvenile hormone titers. Recent sequencing and annotation of the Aedes aegypti genome identified ten putative jhe gene sequences. Analysis of these ten putative jhe gene sequences showed that only three of them, EAT43357, EAT43353 and EAT43354 contained GQSAG motif and showed high sequence similarity with the sequences of jhe genes identified from other insect species. To determine which putative jhe gene(s) code for functi...

  1. Insecticide-Driven Patterns of Genetic Variation in the Dengue Vector Aedes aegypti in Martinique Island

    OpenAIRE

    Sébastien Marcombe; Margot Paris; Christophe Paupy; Charline Bringuier; André Yebakima; Fabrice Chandre; Jean-Philippe David; Vincent Corbel; Laurence Despres

    2013-01-01

    Effective vector control is currently challenged worldwide by the evolution of resistance to all classes of chemical insecticides in mosquitoes. In Martinique, populations of the dengue vector Aedes aegypti have been intensively treated with temephos and deltamethrin insecticides over the last fifty years, resulting in heterogeneous levels of resistance across the island. Resistance spreading depends on standing genetic variation, selection intensity and gene flow among populations. To determ...

  2. Current resistance status to temephos in Aedes aegypti from different regions of Argentina

    OpenAIRE

    G Albrieu Llinás; E Seccacini; CN Gardenal; S Licastro

    2010-01-01

    In Argentina, more than 25,000 cases of dengue were reported in the summer of 2009, even in provinces where the disease was formerly absent. We analysed the susceptibility levels to the larvicide temephos in seven populations of Aedes aegypti, the primary vector of dengue, collected during summer 2007/2008, using the susceptible Rockefeller strain as a control. Although no control failures were observed during the experiment, a majority of the lethal concentration and resistance ratio values ...

  3. PERBANDINGAN EFEKTIVITAS AIR PERASAN KULIT JERUK MANIS DAN TEMEPHOS TERHADAP MORTALITAS LARVA Aedes aegypti

    OpenAIRE

    Ekasari, Ranti; Ishak, Hasanuddin; Manyullei, Syamsuar

    2015-01-01

    Penggunaan larvasida merupakan salah satu cara untuk mengurangi jumlah larva Aedes aegypti yang dapat berkembang menjadi vektor penular penyakit DBD. Larvasida kimia yang paling sering digunakan adalah temephos, selain itu adapula larvasida alami yang dapat digunakan yaitu air perasan kulit jeruk manis. Penelitian ini bertujuan untuk membandingkan efektivitas larvasida kimia yaitu temephos dan larvasida alami yaitu air perasan kulit jeruk manis. Jenis penelitian yang dilakukan adalah peneliti...

  4. Effectiveness of pyriproxyfen and diflubenzuron formulations as larvicides against Aedes aegypti

    OpenAIRE

    Seccacini, Emilia; Lucía Mulas, Alejandro; Harburguer, Laura; Eduardo N Zerba; Licastro, Susana; Masuh, Hector M.

    2008-01-01

    The efficacy of technical pyriproxyfen and diflubenzuron was evaluated at the laboratory level against Aedes aegypti, where we achieved adult emergence inhibition (EI50) values of 0.048 and 1.59 ppb (microg/liter), respectively. We compared these data with values obtained for temephos. We prepared emulsifiable concentrate formulations of pyriproxyfen and diflubenzuron in the laboratory and obtained EI50 values of 0.01 and 0.02 ppb, respectively. We also obtained 100% adult emergence inhibitio...

  5. Temephos Resistance in Aedes aegypti in Colombia Compromises Dengue Vector Control

    OpenAIRE

    Nelson Grisales; Rodolphe Poupardin; Santiago Gomez; Idalyd Fonseca-Gonzalez; Hilary Ranson; Audrey Lenhart

    2013-01-01

    BACKGROUND: Control and prevention of dengue relies heavily on the application of insecticides to control dengue vector mosquitoes. In Colombia, application of the larvicide temephos to the aquatic breeding sites of Aedes aegypti is a key part of the dengue control strategy. Resistance to temephos was recently detected in the dengue-endemic city of Cucuta, leading to questions about its efficacy as a control tool. Here, we characterize the underlying mechanisms and estimate the operational im...

  6. DAMPAK PENGGUNAAN OVITRAP YANG DIBUBUHI TEMEPHOS TERHADAP ANGKA LARVA NYAMUK Aedes aegypti

    OpenAIRE

    M. Hasyimi; Suwarto Suwarto; Suyitno Suyitno; Mardiana Mardiana; Supriyono Supriyono; Sukijo Sukijo

    2012-01-01

    Penelitian lapangan penggunaan ovitrap yang dibubuhi temephos untuk pengendalian vektor demam berdarah dengue (Aedes aegypti) telah dilakukan dari bulan Agustus 1997 sampai dengan Januari 1998 di kelurahan Rawajati dan kelurahan Cipinang Muara Jakarta. Ovitrap yang dibubuhi temephos dipasang pada 25 rumah penduduk sebagai daerah perlakuan, yang dikelilingi 75 rumah dipasangi ovitrap yang sama sebagai daerah penyangga. Masing-masing rumah dipasang 2 buah ovitrap, yang diletakkan di dalam dan d...

  7. Insecticide resistance in Aedes aegypti populations from Ceará, Brazil

    OpenAIRE

    Goulart Marilia OF; de Paiva Neto Clovis C; Barbosa Clarisse; Santana Antonio Euzébio G; de Oliveira Lúcia; da Silva Ulisses; da Silva Éllyda; de Araújo Ana; Paiva Marcelo; Lima Estelita; Wilding Craig; Ayres Constância; de Melo Santos Maria Alice V

    2011-01-01

    Abstract Background Organophosphates and pyrethroids are used widely in Brazil to control Aedes aegypti, the main vector of dengue viruses, under the auspices of the National Programme for Dengue Control. Resistance to these insecticides is widespread throughout Brazil. In Ceará the vector is present in 98% of districts and resistance to temephos has been reported previously. Here we measure resistance to temephos and the pyrethroid cypermethrin in three populations from Ceará and use biochem...

  8. Aedes aegypti sebagai Vektor Demam Berdarah Dengue Berdasarkan Pengamatan di Alam

    Directory of Open Access Journals (Sweden)

    M. Hasyimi

    2012-09-01

    Full Text Available Demam berdarah atau Demam Berdarah Dengue (DBD masih merupakan masalah kesehatan masyarakat. Terutama bagi kota-kota besar yang penduduknya padat dan mobilitas tinggi. Nyamuk Aedes aegypti merupakan penyebar utama penyakit ini, di samping Ae. albopictus. Berhubung sampai saat ini penyakit DBD belum ada obatnya dan vaksin untuk pencegahannya maka pemberantasan penyakit DBD ini dipusatkan kepada pengendalian nyamuk penularnya. Metode pengendalian telah dilakukan dengan bermacam-macam cara, baik secar kimiawi maupun bukan kimiawi.

  9. LARVICIDAL ACTIVITY OF BITTER MELON FRUIT METHANOL EXTRACT AGAINST LARVAE OF Aedes aegypti

    OpenAIRE

    Susilawati; Hermansyah

    2015-01-01

    Dengue hemorrhagic fever is one of the endemic disease and the main health problem in Indonesia. Bitter melon fruit (Momordica charantia L.) was traditionally used as a medicine. The aim of this research was to know larvicidal activity of bitter melon fruit methanol extract against larvae of Aedes aegypti and to know its LC50 value. Bitter melon fruit was extracted by maceration method using methanol as a solvent. The larvicidal activity assay was carried out by calculating the amount d...

  10. Screening of Methanolic Plant Extracts against Larvae of Aedes aegypti and Anopheles stephensi in Mysore

    OpenAIRE

    Thirumalapura Krishnaiah Mohankumar; Kumuda Sathigal Shivanna; Vijayan Valiakottukal Achuttan

    2016-01-01

    Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anoph­eles stephensi to a series of co...

  11. PENENTUAN STATUS RESISTENSI Aedes aegypti DENGAN METODE SUSCEPTIBILITY DI KOTA CIMAHI TERHADAP CYPERMETHRIN

    OpenAIRE

    Firda Yanuar Pradani; Mara Ipa; Rina Marina; Yuneu Yuliasih

    2013-01-01

    ABSTRACT Background:  vector control of DBD usually doing by using insecticides, whether by government or insecticides used in household.  Using to much insecticides for long time can caused resistence of mosquito.  This research aim to know resistance status of Aedes aegypti from endemic rural in district Cimahi to cypermethrin (synthetic pyretroid). Methods:  resistance status knowing by susceptibility methods (WHO standard) with usingimpregnated paper that containing cypermethrin 0,2% and ...

  12. Aedes aegypti on Madeira Island (Portugal): genetic variation of a recently introduced dengue vector

    OpenAIRE

    Goncalo Seixas; Patricia Salgueiro; Ana Clara Silva; Melina Campos; Carine Spenassatto; Matias Reyes-Lugo; Maria Teresa Novo; Paulo Eduardo Martins Ribolla; Joao Pedro Soares da Silva Pinto; Carla Alexandra Sousa

    2013-01-01

    The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal) resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA) genes [cytochrome oxidase subunit I (COI) and NADH dehydrogenase subunit 4 (ND4)] and knockdown resistance ( kdr ) mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosqui...

  13. Open Field Release of Genetically Engineered Sterile Male Aedes aegypti in Malaysia

    OpenAIRE

    Renaud Lacroix; McKemey, Andrew R.; Norzahira Raduan; Lim Kwee Wee; Wong Hong Ming; Teoh Guat Ney; Siti Rahidah A A; Sawaluddin Salman; Selvi Subramaniam; Oreenaiza Nordin; Norhaida Hanum A T; Chandru Angamuthu; Suria Marlina Mansor; Lees, Rosemary S.; Neil Naish

    2012-01-01

    BACKGROUND: Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. METHODOLOGY/PRINC...

  14. Environmental Conditions in Water Storage Drums and Influences on Aedes aegypti inTrinidad, West Indies

    OpenAIRE

    Hemme, Ryan R; Tank, Jennifer L.; Chadee, Dave D; Severson, David W.

    2009-01-01

    Water storage drums are often a primary breeding site for Aedes aegypti in developing countries. Habitat characteristics can impact both adult and larval fitness and survival, which may potentially influence arbovirus transmission. Our objective was to compare fundamental environmental differences in water drums based on the presence or absence of larvae in Trinidad. Drums were categorized according to the larval status, and if the drum was constructed of steel or plastic. Water samples were ...

  15. Open Field Release of Genetically Engineered Sterile Male Aedes aegypti in Malaysia

    OpenAIRE

    Lacroix, Renaud; McKemey, Andrew R.; Raduan, Norzahira; Kwee Wee, Lim; Hong Ming, Wong; Guat Ney, Teoh; Rahidah A.A., Siti; Salman, Sawaluddin; Subramaniam, Selvi; Nordin, Oreenaiza; Hanum A.T., Norhaida; Angamuthu, Chandru; Marlina Mansor, Suria; Lees, Rosemary S; Naish, Neil

    2012-01-01

    Background Dengue is the most important mosquito-borne viral disease. In the absence of specific drugs or vaccines, control focuses on suppressing the principal mosquito vector, Aedes aegypti, yet current methods have not proven adequate to control the disease. New methods are therefore urgently needed, for example genetics-based sterile-male-release methods. However, this requires that lab-reared, modified mosquitoes be able to survive and disperse adequately in the field. Methodology/Princi...

  16. 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.

  17. Semi-Field Evaluation of Metofluthrin-Impregnated Nets on Host-Seeking Aedes aegypti and Anopheles dirus.

    Science.gov (United States)

    Ponlawat, Alongkot; Kankaew, Prasan; Chanaimongkol, Somporn; Pongsiri, Arissara; Richardson, Jason H; Evans, Brian P

    2016-06-01

    The efficacy of a metofluthrin-impregnated net (MIN) known as the "Mushikonazu" on the house entry behavior of female Aedes aegypti and Anopheles dirus mosquitoes was evaluated using a semi-field 50-m tunnel setup. While the MIN is labeled for the control of chironomids and moth flies, this study determined the feasibility of using the device, given its current construction and metofluthrin formulation, as a spatial repellent against mosquitoes. Sentinel and cone bioassays were used to determine the insecticidal effect of the MIN. A spatial activity index (SAI) was calculated to evaluate responses of the mosquitoes. For the spatial repellent evaluation against Ae. aegypti, the overall mean of SAI was slightly less than 0 at wk 1 after the MIN application and then decreased for the last 4 wk showing a preference to treatment tent. For An. dirus, the mean SAI at wk 1 was positive, indicating a presumed repellent effect of the MIN against An. dirus. For the subsequent 4 wk, the SAI was negative, indicating a preference for the MIN. Results suggested that the MIN may not be a promising approach to repel Ae. aegypti and An. dirus under field conditions in Thailand. However, it remains probable that the MIN may be effective as a spatial repellent if modifications are made to the metofluthrin concentration or formulation and/or the construction of the device. PMID:27280351

  18. Semi-Field Evaluation of Metofluthrin-Impregnated Nets on Host-Seeking Aedes aegypti and Anopheles dirus.

    Science.gov (United States)

    Ponlawat, Alongkot; Kankaew, Prasan; Chanaimongkol, Somporn; Pongsiri, Arissara; Richardson, Jason H; Evans, Brian P

    2016-06-01

    The efficacy of a metofluthrin-impregnated net (MIN) known as the "Mushikonazu" on the house entry behavior of female Aedes aegypti and Anopheles dirus mosquitoes was evaluated using a semi-field 50-m tunnel setup. While the MIN is labeled for the control of chironomids and moth flies, this study determined the feasibility of using the device, given its current construction and metofluthrin formulation, as a spatial repellent against mosquitoes. Sentinel and cone bioassays were used to determine the insecticidal effect of the MIN. A spatial activity index (SAI) was calculated to evaluate responses of the mosquitoes. For the spatial repellent evaluation against Ae. aegypti, the overall mean of SAI was slightly less than 0 at wk 1 after the MIN application and then decreased for the last 4 wk showing a preference to treatment tent. For An. dirus, the mean SAI at wk 1 was positive, indicating a presumed repellent effect of the MIN against An. dirus. For the subsequent 4 wk, the SAI was negative, indicating a preference for the MIN. Results suggested that the MIN may not be a promising approach to repel Ae. aegypti and An. dirus under field conditions in Thailand. However, it remains probable that the MIN may be effective as a spatial repellent if modifications are made to the metofluthrin concentration or formulation and/or the construction of the device.

  19. [Larvicidal activity of Anacardium humile Saint Hill oil on Aedes aegypti (Linnaeus, 1762) (Diptera, Culicidae)].

    Science.gov (United States)

    Porto, Karla Rejane de Andrade; Roel, Antonia Railda; Silva, Márcia Marlene da; Coelho, Rosemary Matias; Scheleder, Eloty Justina Dias; Jeller, Alex Haroldo

    2008-01-01

    The objective of this study was to evaluate the potential of Anacardium humile (monkey nuts) against Aedes aegypti larvae. Hexane, ethanol and aqueous extracts and oil from leaves were obtained from plant material collected from the Brazilian savanna. These were tested at concentrations of 1%, 0.5%, 0.25%, 0.125%, 0.05% and 0.0125%, diluted in 1% dimethyl sulfoxide. The dead larvae were counted 24 hours later. The Probit analysis method was used to obtain the LC(50) and the respective confidence intervals. The conclusion was that only the oil extracted from Anacardium humile leaves caused 100% mortality among fourth-instar Aedes aegypti larvae, using concentrations of up to 0.125%. This seems to indicate that the active ingredients are present in the most apolar phase. This indicates that this plant has potential use as a larvicide against Aedes aegypti. However, new tests should be carried out using other plant organs, as well as using other methods and solvents for the extraction.

  20. In silico models for predicting vector control chemicals targeting Aedes aegypti.

    Science.gov (United States)

    Devillers, J; Lagneau, C; Lattes, A; Garrigues, J C; Clémenté, M M; Yébakima, A

    2014-01-01

    Human arboviral diseases have emerged or re-emerged in numerous countries worldwide due to a number of factors including the lack of progress in vaccine development, lack of drugs, insecticide resistance in mosquitoes, climate changes, societal behaviours, and economical constraints. Thus, Aedes aegypti is the main vector of the yellow fever and dengue fever flaviviruses and is also responsible for several recent outbreaks of the chikungunya alphavirus. As for the other mosquito species, the A. aegypti control relies heavily on the use of insecticides. However, because of increasing resistance to the different families of insecticides, reduction of Aedes populations is becoming increasingly difficult. Despite the unquestionable utility of insecticides in fighting mosquito populations, there are very few new insecticides developed and commercialized for vector control. This is because the high cost of the discovery of an insecticide is not counterbalanced by the 'low profitability' of the vector control market. Fortunately, the use of quantitative structure-activity relationship (QSAR) modelling allows the reduction of time and cost in the discovery of new chemical structures potentially active against mosquitoes. In this context, the goal of the present study was to review all the existing QSAR models on A. aegypti. The homology and pharmacophore models were also reviewed. Specific attention was paid to show the variety of targets investigated in Aedes in relation to the physiology and ecology of the mosquito as well as the diversity of the chemical structures which have been proposed, encompassing man-made and natural substances.

  1. Apoptosis-related genes control autophagy and influence DENV-2 infection in the mosquito vector, Aedes aegypti.

    Science.gov (United States)

    Eng, Matthew W; van Zuylen, Madeleine N; Severson, David W

    2016-09-01

    The mosquito Aedes aegypti is the primary urban vector for dengue virus (DENV) worldwide. Insight into interactions occurring between host and pathogen is important in understanding what factors contribute to vector competence. However, many of the molecular mechanisms for vector competence remain unknown. Our previous global transcriptional analysis suggested that differential expression of apoptotic proteins is involved in determining refractoriness vs susceptibility to DENV-2 infection in Ae. aegypti females following a DENV-infected blood meal. To determine whether DENV-refractory Ae. aegypti showed more robust apoptosis upon infection, we compared numbers of apoptotic cells from midguts of refractory and susceptible strains and observed increased numbers of apoptotic cells in only the refractory strain upon DENV-2 infection. Thereafter, we manipulated apoptosis through dsRNA interference of the initiator caspase, Aedronc. Unexpectedly, dsAedronc-treated females showed both decreased frequency of disseminated infection and decreased virus titer in infected individuals. Insect caspases have also previously been identified as regulators of the cellular recycling process known as autophagy. We observed activation of autophagy in midgut and fat body tissues following a blood meal, as well as programmed activation of several apoptosis-related genes, including the effector caspase, Casps7. To determine whether autophagy was affected by caspase knockdown, we silenced Aedronc and Casps7, and observed reduced activation of autophagy upon silencing. Our results provide evidence that apoptosis-related genes are also involved in regulating autophagy, and that Aedronc may play an important role in DENV-2 infection success in Ae. aegypti, possibly through its regulation of autophagy. PMID:27418459

  2. Larvicidal effect of andiroba oil, Carapa guianensis (Meliaceae), against Aedes aegypti.

    Science.gov (United States)

    Silva, Onilda S; Prophiro, Josiane S; Nogared, Juliana C; Kanis, Luiz; Emerick, Sheila; Blazius, Rene D; Romão, Pedro R T

    2006-12-01

    The aim of this work was to evaluate the larvicidal effect of andiroba oil, Carapa guyanensis, against 2 strains of Aedes aegypti. After 8 h after exposure to oil, the lethal concentration (LC)90 and LC95 values for the GCZ (temephos-resistant) strain larvae were 80 and 86 ppm (1st instars), 98 and 106 (2nd instars), 166 and 182 (3rd instars), and 192 and 202 ppm (4th instars), respectively. TheLC90 and LC95 values for the Rockefeller strain larvae were 164 and 182 ppm (1st instars), 212 and 224 (2nd instars), 210 and 226 (3rd instars), and 450 and 490 ppm (4th instars), respectively. Comparison of the 2 laboratory strains of Ae. aegypti in the present study demonstrated significant variation in the susceptibility of larvae to andiroba oil. Whether a higher susceptibility of field populations of Ae. aegypti to andiroba oil occurs remains to be investigated. PMID:17304939

  3. CPB1 of Aedes aegypti Interacts with DENV2 E Protein and Regulates Intracellular Viral Accumulation and Release from Midgut Cells

    Directory of Open Access Journals (Sweden)

    Hong-Wai Tham

    2014-12-01

    Full Text Available Aedes aegypti is a principal vector responsible for the transmission of dengue viruses (DENV. To date, vector control remains the key option for dengue disease management. To develop new vector control strategies, a more comprehensive understanding of the biological interactions between DENV and Ae. aegypti is required. In this study, a cDNA library derived from the midgut of female adult Ae. aegypti was used in yeast two-hybrid (Y2H screenings against DENV2 envelope (E protein. Among the many interacting proteins identified, carboxypeptidase B1 (CPB1 was selected, and its biological interaction with E protein in Ae. aegypti primary midgut cells was further validated. Our double immunofluorescent assay showed that CPB1-E interaction occurred in the endoplasmic reticulum (ER of the Ae. aegypti primary midgut cells. Overexpression of CPB1 in mosquito cells resulted in intracellular DENV2 genomic RNA or virus particle accumulation, with a lower amount of virus release. Therefore, we postulated that in Ae. aegypti midgut cells, CPB1 binds to the E protein deposited on the ER intraluminal membranes and inhibits DENV2 RNA encapsulation, thus inhibiting budding from the ER, and may interfere with immature virus transportation to the trans-Golgi network.

  4. A study on container breeding mosquitoes with special reference to Aedes (Stegomyia aegypti and Aedes albopictus in Thiruvananthapuram district, India

    Directory of Open Access Journals (Sweden)

    K. Vijayakumar

    2014-01-01

    Full Text Available Background & objectives: The district of Thiruvananthapuram reports the maximum number of cases of dengue in the state of Kerala. To determine the larval diversity, density and breeding site preferences of Aedes mosquitoes, during pre-monsoon and monsoon periods in urban and rural areas of Thiruvananthapuram district. Methods: Based on the daily reports of dengue cases, 70 clusters were identified in Thiruvananthapuram district. A cross-sectional larval survey was done in the domestic and peri-domestic areas of 1750 houses, using the WHO standard techniques. The larval indices were calculated, and the larvae were identified by using taxonomic keys. Urban and rural differences and the variations during pre-monsoon and monsoon seasons were also studied. Results: In the surveyed houses, 15% had mosquito breeding, with 88% having Aedes larvae. The house index, container index and the breteau index were 13.08, 13.28 and 16.57%, respectively. About 86% of the clusters were found positive for Aedes albopictus and 11% for Ae. aegypti. Aedes albopictus was distributed almost equally in rural and urban clusters, whereas the distribution of Ae. aegypti was significantly higher in urban areas (p = 0.03. The most common water holding containers found (outdoor were of plastic, followed by coconut shells. The breeding preference ratio was highest for tyres. Significantly lesser positivity was found for containers during monsoon period when compared to pre-monsoon period. Conclusion: The geographical distribution of Ae. albopictus is significantly high in peri-domestic areas and, therefore, its epidemiological role in the widespread disease occurrence needs to be studied. The discarded tyres being the most preferred breeding sites, where IEC activities will help in source reduction.

  5. Molecular characterization of Aedes aegypti (L. (Diptera: Culicidae of Easter Island based on analysis of the mitochondrial ND4 gene

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    Claudia Andrea Núñez

    2016-06-01

    Full Text Available ABSTRACT Aedes aegypti mosquitoes are the main vector of viruses Dengue, Zika and Chikungunya. Shortly after the first report of the dengue vector Ae. aegypti in Easter Island (Rapa Nui in late 2000, the first disease outbreak dengue occurred. Viral serotyping during the 2002 outbreak revealed a close relationship with Pacific DENV-1 genotype IV viruses, supporting the idea that the virus most likely originated in Tahiti. Mitochondrial NADH dehydrogenase subunit 4 (ND4 DNA sequences generated from 68 specimens of Ae. aegypti from Easter Island reporting a unique finding of a single maternal lineage of Ae. aegypti on Easter Island.

  6. Potencial de Bacillus thuringiensis israelensis Berliner no controle de Aedes aegypti Potential of Bacillus thuringiensis israelensis Berliner for controlling Aedes aegypti

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    Ricardo Antonio Polanczyk

    2003-12-01

    Full Text Available Relata-se a importância da bactéria entomopatogênica Bacillus thuringiensis israelensis para o controle de Aedes aegypti. São abordados a utilização e potencial de B. thuringiensis israelensis contra o mosquito vetor da dengue. Outros aspectos são discutidos como a evolução da resistência dos insetos em relação aos inseticidas químicos e as vantagens e desvantagens do controle microbiano como estratégia de controle. É dada ênfase à importância da utilização desta bactéria no Brasil como alternativa para resolver o problema em questão sem afetar o ambiente, o homem e outros vertebrados nas áreas de risco.The importance of the entomopathogenic bacterium Bacillus thuringiensis israelensis in the control of Aedes aegypti is presented. The use and potential of B. thuringiensis israelensis against the mosquito vector of dengue fever is described. Other aspects such as insect's resistance development against chemicals and advantages and constraints of using microbial control are discussed. Emphasis is given to the importance of the use of this bacterium in Brazil, which could contribute significantly to solving the mosquito problem without affecting the environment, humans and others invertebrate organisms in critical regions.

  7. Linking oviposition site choice to offspring fitness in Aedes aegypti: consequences for targeted larval control of dengue vectors.

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    Jacklyn Wong

    Full Text Available BACKGROUND: Current Aedes aegypti larval control methods are often insufficient for preventing dengue epidemics. To improve control efficiency and cost-effectiveness, some advocate eliminating or treating only highly productive containers. The population-level outcome of this strategy, however, will depend on details of Ae. aegypti oviposition behavior. METHODOLOGY/PRINCIPAL FINDINGS: We simultaneously monitored female oviposition and juvenile development in 80 experimental containers located across 20 houses in Iquitos, Peru, to test the hypothesis that Ae. aegypti oviposit preferentially in sites with the greatest potential for maximizing offspring fitness. Females consistently laid more eggs in large vs. small containers (β = 9.18, p<0.001, and in unmanaged vs. manually filled containers (β = 5.33, p<0.001. Using microsatellites to track the development of immature Ae. aegypti, we found a negative correlation between oviposition preference and pupation probability (β = -3.37, p<0.001. Body size of emerging adults was also negatively associated with the preferred oviposition site characteristics of large size (females: β = -0.19, p<0.001; males: β = -0.11, p = 0.002 and non-management (females: β = -0.17, p<0.001; males: β = -0.11, p<0.001. Inside a semi-field enclosure, we simulated a container elimination campaign targeting the most productive oviposition sites. Compared to the two post-intervention trials, egg batches were more clumped during the first pre-intervention trial (β = -0.17, P<0.001, but not the second (β = 0.01, p = 0.900. Overall, when preferred containers were unavailable, the probability that any given container received eggs increased (β = 1.36, p<0.001. CONCLUSIONS/SIGNIFICANCE: Ae. aegypti oviposition site choice can contribute to population regulation by limiting the production and size of adults. Targeted larval control strategies may unintentionally lead to

  8. The effect of virus-blocking Wolbachia on male competitiveness of the dengue vector mosquito, Aedes aegypti.

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    Michal Segoli

    2014-12-01

    Full Text Available The bacterial endosymbiont Wolbachia blocks the transmission of dengue virus by its vector mosquito Aedes aegypti, and is currently being evaluated for control of dengue outbreaks. Wolbachia induces cytoplasmic incompatibility (CI that results in the developmental failure of offspring in the cross between Wolbachia-infected males and uninfected females. This increases the relative success of infected females in the population, thereby enhancing the spread of the beneficial bacterium. However, Wolbachia spread via CI will only be feasible if infected males are sufficiently competitive in obtaining a mate under field conditions. We tested the effect of Wolbachia on the competitiveness of A. aegypti males under semi-field conditions.In a series of experiments we exposed uninfected females to Wolbachia-infected and uninfected males simultaneously. We scored the competitiveness of infected males according to the proportion of females producing non-viable eggs due to incompatibility. We found that infected males were equally successful to uninfected males in securing a mate within experimental tents and semi-field cages. This was true for males infected by the benign wMel Wolbachia strain, but also for males infected by the virulent wMelPop (popcorn strain. By manipulating male size we found that larger males had a higher success than smaller underfed males in the semi-field cages, regardless of their infection status.The results indicate that Wolbachia infection does not reduce the competitiveness of A. aegypti males. Moreover, the body size effect suggests a potential advantage for lab-reared Wolbachia-males during a field release episode, due to their better nutrition and larger size. This may promote Wolbachia spread via CI in wild mosquito populations and underscores its potential use for disease control.

  9. Presumed unconstrained dispersal of Aedes aegypti in the city of Rio de Janeiro, Brazil Dispersión ilimitada de Aedes aegypti en la ciudad de Río de Janeiro, Brasil Dispersão de Aedes aegypti em local presumidamente sem barreira limitante ao vôo na cidade do Rio de Janeiro

    Directory of Open Access Journals (Sweden)

    Rafael Maciel-de-Freitas

    2009-02-01

    Full Text Available OBJECTIVE: To evaluate dispersal of Aedes aegypti females in an area with no container manipulation and no geographic barriers to constrain mosquito flight. METHODS: A mark-release-recapture experiment was conducted in December 2006, in the dengue endemic urban district of Olaria in Rio de Janeiro, Southeastern Brazil, where there is no evident obstacle to the dispersal of Ae. aegypti females. Mosquito traps were installed in 192 houses (96 Adultraps and 96 MosquiTRAPs. RESULTS: A total of 725 dust-marked gravid females were released and recapture rate was 6.3%. Ae. aegypti females traveled a mean distance of 288.12 m and their maximum displacement was 690 m; 50% and 90% of females flew up to 350 m and 500.2 m, respectively. CONCLUSIONS: Dispersal of Ae. aegypti females in Olaria was higher than in areas with physical and geographical barriers. There was no evidence of a preferred direction during mosquito flight, which was considered random or uniform from the release point.OBJETIVO: Evaluar la dispersión de hembras de Aedes aegypti en un área sin manipulación de recipientes y sin barreras geográficas que limiten el vuelo del mosquito. MÉTODOS: Se realizó un experimento de marcaje y recaptura en diciembre de 2006, en el distrito urbano Olaria, Rio de Janeiro (Sureste de Brasil, área endémica para dengue, donde no hay obstáculo evidente para la dispersión de hembras de Ae. aegypti. Trampas para mosquitos fueron instaladas en 192 casas (96 Adultraps y 96 MosquiTraps. RESULTADOS: Un total de 725 hembras grávidas marcadas con polvo fueron liberadas y recapturadas siendo la tasa de 6,3%. Las hembras de Ae. Aegypti viajaron una distancia promedio de 288,12 m y su máximo desplazamiento fue de 690 m; 50% y 90% de las hembras volaron hasta los 350 m y 500,2 m, respectivamente. CONCLUSIONES: Dispersión de las hembras de Ae. aegypti en Olaria fue mayor que en las áreas con barreras físicas y geográficas. No hube evidencia de una direcci

  10. PENGARUH SUMBER NUTRISI TERHADAP UMUR VEKTOR DEMAM BERDARAH DENGUE Aedes aegypti DI LABORATORIUM

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    Riyani Setiyaningsih

    2011-12-01

    Full Text Available ENGLISHAedes aegypti is a major vector of DHF in several areas of Indonesia. The longetivity of Ae. aegypti female mosquitoes could be up to 10 days nature. Whereas in laboratorium condition, they could survive for 2 months by feeding on sugar water and blood. Based on that background, this research is intended to find out the influence of the nutrition sources. Such as sugar solution, vitamin solution and blood of rabbit. As a control, nutrition will not be given at all. The death procentage of the mosquitoes was examined every day until the death reached up to 100%. The result showed that there was no significant difference between giving variations of sugar solution, vitamin and blood toward the longivity at Ae. aegypti. The 100% mortality of female mosquitos, fed on sugar solution, vitamin, blood and the control were observed on 22 days, 20 days, 18 days and 13 daysINDONESIAAedes aegypti merupakan vektor utama Demam Berdarah Dangue ( DBD di beberapa darah di Indonesia. Umur nyamuk Ae. aegypti betina di alam dapat mencapai 10 hari, sedangkan pada kondisi laboratorium Ae. aegypti dapat bertahan hidup selama 2 bulan dengan menggunakan nutrisi berupa air gula dan darah. Penelitian ini bertujuan untuk mengetahui pengaruh sumber nutrisi yang berupa larutan gula, larutan vitamin (provit dan darah terhadap umur nyamuk Ae. aegypti. Nyamuk Ae. aegypti jantan dan betina di masukkan di dalam gelas plastik. Nyamuk Ae. aegypti diberikan beberapa variasi perlakuan yaitu nutrisi yang berupa larutan gula, larutan vitamin (provit, dan darah marmut. Sebagai kontrol tidak diberikan nutrisi apapun. Persentase kematian nyamuk diamati tiap hari sampai kematian mencapai 100%. Hasil penelitian menunjukkan bahwa tidak ada perbedaan yang nyata antara pemberian variasi nutrisi larutan gula, vitamin, dan darah terhadap umur Ae. aegypti. Kematian 100% pada nyamuk betina yang diberi nutrisi gula, vitamin, darah , dan kontrol masing-masing terjadi setelah, 22 hari, 20 hari

  11. Insecticide susceptibility status of Aedes aegypti and Anopheles stephensi larvae against temephos in Delhi, India

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    R.K. Singh

    2014-09-01

    Full Text Available Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortality was recorded from Sangam Vihar (98.22% and lowest was recorded from Majnu ka tila (64.88%. Ae. aegypti larvae collected from Sangam Vihar locality was found fully susceptible to temephos, from two localities viz. Uttam Nagar and Pitampura of study area were tolerant to temephos, and from five localities viz. Majnu ka tila, Shastri Park, Mayur Vihar II, Tilak Bridge and Nagal Dewat showed development of resistance against temephos at diagnostic concentrations. However, larval populations of An. stephensi were fully susceptible to temephos in all the localities. The present study indicates the possible development of resistance against temephos in the larvae of Ae. aegypti in some areas in Delhi.

  12. QTL mapping of genome regions controlling temephos resistance in larvae of the mosquito Aedes aegypti.

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    Guadalupe Del Carmen Reyes-Solis

    2014-10-01

    Full Text Available The mosquito Aedes aegypti is the principal vector of dengue and yellow fever flaviviruses. Temephos is an organophosphate insecticide used globally to suppress Ae. aegypti larval populations but resistance has evolved in many locations.Quantitative Trait Loci (QTL controlling temephos survival in Ae. aegypti larvae were mapped in a pair of F3 advanced intercross lines arising from temephos resistant parents from Solidaridad, México and temephos susceptible parents from Iquitos, Peru. Two sets of 200 F3 larvae were exposed to a discriminating dose of temephos and then dead larvae were collected and preserved for DNA isolation every two hours up to 16 hours. Larvae surviving longer than 16 hours were considered resistant. For QTL mapping, single nucleotide polymorphisms (SNPs were identified at 23 single copy genes and 26 microsatellite loci of known physical positions in the Ae. aegypti genome. In both reciprocal crosses, Multiple Interval Mapping identified eleven QTL associated with time until death. In the Solidaridad×Iquitos (SLD×Iq cross twelve were associated with survival but in the reciprocal IqxSLD cross, only six QTL were survival associated. Polymorphisms at acetylcholine esterase (AchE loci 1 and 2 were not associated with either resistance phenotype suggesting that target site insensitivity is not an organophosphate resistance mechanism in this region of México.Temephos resistance is under the control of many metabolic genes of small effect and dispersed throughout the Ae. aegypti genome.

  13. Genome Investigations of Vector Competence in Aedes aegypti to Inform Novel Arbovirus Disease Control Approaches

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    David W. Severson

    2016-10-01

    Full Text Available Dengue (DENV, yellow fever, chikungunya, and Zika virus transmission to humans by a mosquito host is confounded by both intrinsic and extrinsic variables. Besides virulence factors of the individual arboviruses, likelihood of virus transmission is subject to variability in the genome of the primary mosquito vector, Aedes aegypti. The “vectorial capacity” of A. aegypti varies depending upon its density, biting rate, and survival rate, as well as its intrinsic ability to acquire, host and transmit a given arbovirus. This intrinsic ability is known as “vector competence”. Based on whole transcriptome analysis, several genes and pathways have been predicated to have an association with a susceptible or refractory response in A. aegypti to DENV infection. However, the functional genomics of vector competence of A. aegypti is not well understood, primarily due to lack of integrative approaches in genomic or transcriptomic studies. In this review, we focus on the present status of genomics studies of DENV vector competence in A. aegypti as limited information is available relative to the other arboviruses. We propose future areas of research needed to facilitate the integration of vector and virus genomics and environmental factors to work towards better understanding of vector competence and vectorial capacity in natural conditions.

  14. Aedes aegypti on Madeira Island (Portugal: genetic variation of a recently introduced dengue vector

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    Goncalo Seixas

    2013-01-01

    Full Text Available The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA genes [cytochrome oxidase subunit I (COI and NADH dehydrogenase subunit 4 (ND4] and knockdown resistance ( kdr mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources. The Ae. aegypti population from Madeira showed extremely low mtDNA genetic variability, with a single haplotype for COI and ND4. We also detected the presence of two important kdr mutations and the quasi-fixation of one of these mutations (F1534C. These results are consistent with a unique recent founder event that occurred on the island of Ae. aegypti mosquitoes that carry kdr mutations associated with insecticide resistance. Finally, we also report the presence of the F1534C kdr mutation in the Brazil and Venezuela populations. To our knowledge, this is the first time this mutation has been found in South American Ae. aegypti mosquitoes. Given the present risk of Ae. aegypti re-invading continental Europe from Madeira and the recent dengue outbreaks on the island, this information is important to plan surveillance and control measures.

  15. Excito-repellency of essential oils against an Aedes aegypti (L.) field population in Thailand.

    Science.gov (United States)

    Boonyuan, Wasana; Grieco, John P; Bangs, Michael J; Prabaripai, Atchariya; Tantakom, Siripun; Chareonviriyaphap, Theeraphap

    2014-06-01

    An investigation of the behavioral responses of Aedes aegypti (= Stegomyia aegypti) to various concentrations of essential oils (2.5, 5, and 10%) extracted from hairy basil (Ocimum americanum Linn), ginger (Zingiber officinale Roscoe), lemongrass (Cymbopogon citratus Stapf), citronella grass (Cymbopogon nardus Rendle), and plai (Zingiber cassumunar Roxb) were performed using an excito-repellency test chamber. Results showed that Ae. aegypti exhibited varying levels of escape response in both the contact and noncontact chambers in response to different essential oils. The magnitude of the behaviors changed in a dose-response fashion depending on the percent volume to volume concentration of oil used. A 2.5% concentration of hairy basil oil produced a significantly greater escape response compared to the other extracts at the same concentration (Pinsecticidal activity to Ae. aegypti, with LC50 values of 6.3 and 6.7 percent, respectively. We conclude that the essential oils from native plants tested, and likely many other extracts found in plants, have inherent repellent and irritant qualities that should to be screened and optimized for their behavior-modifying properties against Ae. aegypti and other biting arthropods of public health and pest importance.

  16. Laboratory and field evaluation of the effects of the neonicotinoid imidacloprid on the oviposition response of Aedes (Stegomyia aegypti Linnaeus (Diptera: Culicidae

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    Gloria Elsa Antonio-Arreola

    2011-12-01

    Full Text Available In this paper, we assessed the suitability of using the neonicotinoid imidacloprid with standard ovitraps by evaluating the ovicidal properties of imidacloprid and its influence on the oviposition response of gravid females of Aedes (Stegomyia aegypti Linnaeus (Diptera: Culicidae. First, we calculated the imidacloprid lethal dose 99 (LD99 by exposing third instar larvae of the target species to different concentrations of the insecticide. Next, Ae. aegypti eggs were exposed to the imidacloprid LD99 for 24 h and hatching inhibition was recorded. Finally, we investigated any potential repellent effect of the imidacloprid solution on the oviposition response of gravid Aedes females in field and laboratory conditions. The LD99 obtained from larvae tests proved to be sufficient to keep any exposed eggs from hatching. No repellent effect was observed; females laid as many eggs in imidacloprid-treated ovitraps as in traps containing either clean water or temephos-treated water in both field and laboratory conditions. Our results indicate that imidacloprid is a suitable insecticide for treating ovitraps against Ae. aegypti.

  17. Increased fecundity of Aedes aegypti fed human blood before release in a mark-recapture study in Puerto Rico.

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    Morrison, A C; Costero, A; Edman, J D; Clark, G G; Scott, T W

    1999-06-01

    Laboratory experiments suggest that utilization of blood rather than natural sugar sources for energetic needs affords female Aedes aegypti a reproductive advantage over conspecifics that use sugar. To test this hypothesis under field conditions, we carried out a mark-release-recapture study in Florida, PR. Adult females (F1) reared from field-collected eggs were provided with a diet of human blood alone or human blood plus a 20% honey solution before their release. Backpack aspirators were used to collect mosquitoes from release houses for 5 consecutive days beginning the 2nd day after release. Survival was estimated from the slope of the regression line of the log-transformed daily number of recaptures for each treatment group. To compare fecundity of the treatment groups, each recaptured female was dissected, ovaries were removed, oocytes counted, and Christophers' stages of oocyte development scored. Recapture rates were 30% for the blood-only group and 23% for blood plus honey group. The daily survival rate of the blood-only group (55%) was not statistically different from that of the blood plus honey group (69%) (t = 0.32, P > 0.05). By analysis of variance, fecundity (average number of stage III-V oocytes) was significantly higher in the females fed human blood alone (n = 103, 109 oocytes/female) than in the group fed on blood and honey (n = 50, 95 oocytes/female) (P = 0.0007). The observed gonotrophic cycle length of the recaptured females ranged from 3 to 7 days. Results from our field study are consistent with laboratory life-table experiments that suggest feeding exclusively on human blood provides a reproductive advantage for female A. aegypti. PMID:10412105

  18. Effect of two commercial herbicides on life history traits of a human disease vector, Aedes aegypti, in the laboratory setting.

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    Morris, Alexandra; Murrell, Ebony G; Klein, Talan; Noden, Bruce H

    2016-07-01

    Some mosquito species utilize the small niches of water that are abundant in farmland habitats. These niches are susceptible to effects from agricultural pesticides, many of which are applied aerially over large tracts of land. One principal form of weed control in agricultural systems involves the development of herbicide-tolerant crops. The impact of sub-agricultural levels of these herbicides on mosquito survival and life-history traits of resulting adults have not been determined. The aim of this study was to test the effect of two commercial herbicides (Beyond and Roundup) on the survivorship, eclosion time, and body mass of Aedes aegypti. First instar A. aegypti larvae were exposed to varying concentrations (270, 550 and 820 μg/m(2) of glyphosate and 0.74, 1.49, 2.24 μL imazamox/m(2)), all treatments being below recommended application rates, of commercial herbicides in a controlled environment and resulting adult mosquitoes were collected and weighed. Exposure to Roundup had a significant negative effect on A. aegypti survivorship at medium and high sub-agricultural application concentrations, and negatively affected adult eclosion time at the highest concentration. However, exposure to low concentrations of Beyond significantly increased A. aegypti survivorship, although adult female mass was decreased at medium sub-agricultural concentrations. These results demonstrate that low concentrations of two different herbicides, which can occur in rural larval habitats as a result of spray drift, can affect the same species of mosquito in both positive and negative ways depending on the herbicide applied. The effects of commercial herbicides on mosquito populations could have an important effect on disease transmission within agricultural settings, where these and other herbicides are extensively applied to reduce weed growth. PMID:26965703

  19. Toxicological evaluation of essential oil from the leaves of Croton tetradenius (Euphorbiaceae) on Aedes aegypti and Mus musculus.

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    Carvalho, Karine da Silva; E Silva, Sandra Lúcia da Cunha; de Souza, Ivone Antonia; Gualberto, Simone Andrade; da Cruz, Rômulo Carlos Dantas; Dos Santos, Frances Regiane; de Carvalho, Mário Geraldo

    2016-09-01

    For control of Aedes aegypti, the main vector of dengue, botanical insecticides can be a viable alternative. Herein, we evaluated the chemical composition and insecticidal activity of the essential oils of the leaves of Croton tetradenius on Ae. aegypti larvae and adults. We also evaluated the acute toxicity in Mus musculus. The essential oil chemical analysis was performed using chromatography coupled with mass spectrometry and flame ionization detection. Female mice were used for assessing toxicity according to the Organization for Economic Cooperation and Development's Test Guideline 423/2001. Doses administered to mice orally and intraperitoneally were 5, 50, 300, and 2000 mg kg(-1). There was a greater toxic effect on larvae (LC50 = 0.152 mg mL(-1) and LC90 = 0.297 mg mL(-1)) and on adults (LC50 = 1.842 mg mL(-1) and LC90 = 3.156 mg mL(-1)) of Ae. aegypti after 24 h of exposure, when compared to other periods of exposure. Chemical analysis revealed 26 components, with camphor (25.49 %) as the major component. The acute toxicity via the intraperitoneal route identified an LD50 = 200 mg kg(-1) and by the oral route an LD50 = 500 mg kg(-1). Thus, the essential oil of C. tetradenius presents insecticidal potential for Ae. aegypti and has high safety threshold at the concentrations evaluated in this study. PMID:27169864

  20. Repellent and insecticidal efficacy of a new combination of fipronil and permethrin against three mosquito species (Aedes albopictus, Aedes aegypti and Culex pipiens) on dogs

    OpenAIRE

    Fankhauser, Becky; Dumont, Pascal; Hunter, James S; McCall, John W.; Kaufmann, Christian; Mathis, Alexander; Young, David R.; Carroll, Scott P; McCall, Scott; Chester, S. Theodore; Soll, Mark D

    2015-01-01

    Background Three laboratory studies were conducted to assess the repellent and insecticidal efficacy of a combination of fipronil and permethrin (Frontline Tri- Act®/Frontect®) against three mosquito species (Aedes albopictus, Aedes aegypti and Culex pipiens) on dogs. Methods In each study, 16 healthy adult dogs were allocated to two groups. Eight dogs were treated with the new topical spot-on combination of fipronil and permethrin on Day 0 and the other eight dogs served as untreated control...

  1. Repellent and insecticidal efficacy of a new combination of fipronil and permethrin against three mosquito species (Aedes albopictus, Aedes aegypti and Culex pipiens) on dogs

    OpenAIRE

    Fankhauser, Becky; Dumont, Pascal; Hunter, James S; McCall, John W.; Kaufmann, Christian; Mathis, Alexander; Young, David R.; Carroll, Scott P; McCall, Scott; Chester, S. Theodore; Soll, Mark D

    2015-01-01

    BACKGROUND: Three laboratory studies were conducted to assess the repellent and insecticidal efficacy of a combination of fipronil and permethrin (Frontline Tri- Act®/Frontect®) against three mosquito species (Aedes albopictus, Aedes aegypti and Culex pipiens) on dogs. METHODS: In each study, 16 healthy adult dogs were allocated to two groups. Eight dogs were treated with the new topical spot-on combination of fipronil and permethrin on Day 0 and the other eight dogs served as untreated co...

  2. Aedes aegypti and Aedes albopictus (Diptera: Culicidae): coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization

    OpenAIRE

    Josiane Somariva Prophiro; Onilda Santos Silva; Jonny Edward Duque Luna; Carla Fernanda Piccoli; Luiz Alberto Kanis; Mario Antonio Navarro da Silva

    2011-01-01

    INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggr...

  3. Surveillance and control of Aedes aegypti in epidemic areas of Taiwan.

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    Lin, T H

    1994-12-01

    Aedes aegypti is the main, if not the only, vector of dengue fever in Taiwan. The dengue epidemics that have occurred in Taiwan correlate with the distribution of Aedes aegypti which is limited to south of the Tropic of Cancer. During the 1987 outbreak of dengue fever in Taiwan, the average larval density for the months July-December in the five cities and counties of southern Taiwan was 2,284 larvae per 100 households. After control measures were taken, the average annual larval density in the years from 1988 to 1993 declined to 1,580, 671, 442, 178, 110, and 88 larvae per 100 households, respectively. During 1987-1988, the number of confirmed cases and the Breteau index of Aedes aegypti showed an obvious positive relationship (r = 0.74) in the most heavily infected 25 cities and towns. Our Institute has conducted eight training courses since 1989 for 176 health workers who serve in their respective areas as local scouts for monitoring Aedes larval density. The number of cities and towns surveyed by them in the years 1990-1993 was 116, 149, 254, and 156, respectively. The number of households covered by space spraying with permethrin was 43, 183 in 1991, 11,186 in 1992 and 4,856 in 1993. Residual spraying with alphacypermethrin was applied to houses in areas where the Breteau index was above 35. The number of houses treated in the years 1990-1993 was 4,735, 32,279, 33,726 and 17,848, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  4. Ecological modeling of Aedes aegypti (L. pupal production in rural Kamphaeng Phet, Thailand.

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    Jared Aldstadt

    Full Text Available BACKGROUND: Aedes aegypti (L. is the primary vector of dengue, the most important arboviral infection globally. Until an effective vaccine is licensed and rigorously administered, Ae. aegypti control remains the principal tool in preventing and curtailing dengue transmission. Accurate predictions of vector populations are required to assess control methods and develop effective population reduction strategies. Ae. aegypti develops primarily in artificial water holding containers. Release recapture studies indicate that most adult Ae. aegypti do not disperse over long distances. We expect, therefore, that containers in an area of high development site density are more likely to be oviposition sites and to be more frequently used as oviposition sites than containers that are relatively isolated from other development sites. After accounting for individual container characteristics, containers more frequently used as oviposition sites are likely to produce adult mosquitoes consistently and at a higher rate. To this point, most studies of Ae. aegypti populations ignore the spatial density of larval development sites. METHODOLOGY: Pupal surveys were carried out from 2004 to 2007 in rural Kamphaeng Phet, Thailand. In total, 84,840 samples of water holding containers were used to estimate model parameters. Regression modeling was used to assess the effect of larval development site density, access to piped water, and seasonal variation on container productivity. A varying-coefficients model was employed to account for the large differences in productivity between container types. A two-part modeling structure, called a hurdle model, accounts for the large number of zeroes and overdispersion present in pupal population counts. FINDINGS: The number of suitable larval development sites and their density in the environment were the primary determinants of the distribution and abundance of Ae. aegypti pupae. The productivity of most container types

  5. Imidacloprid impairs the post-embryonic development of the midgut in the yellow fever mosquito Stegomyia aegypti (=Aedes aegypti).

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    Fernandes, K M; Gonzaga, W G; Pascini, T V; Miranda, F R; Tomé, H V V; Serrão, J E; Martins, G F

    2015-09-01

    The mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) is a vector for the dengue and yellow fever viruses. As blood digestion occurs in the midgut, this organ constitutes the route of entry of many pathogens. The effects of the insecticide imidacloprid on the survival of St. aegypti were investigated and the sub-lethal effects of the insecticide on midgut development were determined. Third instar larvae were exposed to different concentrations of imidacloprid (0.15, 1.5, 3.0, 6.0 and 15.0 p.p.m.) and survival was monitored every 24 h for 10 days. Midguts from imidacloprid-treated insects at different stages of development were dissected and processed for analyses by transmission electron microscopy, immunofluorescence microscopy and terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assays. Imidacloprid concentrations of 3.0 and 15.0 p.p.m. were found to affect midgut development similarly. Digestive cells of the fourth instar larvae (L4) midgut exposed to imidacloprid had more multilamellar bodies, abundantly found in the cell apex, and more electron-lucent vacuoles in the basal region compared with those from untreated insects. Moreover, imidacloprid interfered with the differentiation of regenerative cells, dramatically reducing the number of digestive and endocrine cells and leading to malformation of the midgut epithelium in adults. The data demonstrate that imidacloprid can reduce the survival of mosquitoes and thus indicate its potentially high efficacy in the control of St. aegypti populations.

  6. Leucokinin mimetic elicits aversive behavior in mosquito Aedes aegypti (L.) and inhibits the sugar taste neuron.

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    Kwon, Hyeogsun; Ali Agha, Moutaz; Smith, Ryan C; Nachman, Ronald J; Marion-Poll, Frédéric; Pietrantonio, Patricia V

    2016-06-21

    Insect kinins (leucokinins) are multifunctional peptides acting as neurohormones and neurotransmitters. In females of the mosquito vector Aedes aegypti (L.), aedeskinins are known to stimulate fluid secretion from the renal organs (Malpighian tubules) and hindgut contractions by activating a G protein-coupled kinin receptor designated "Aedae-KR." We used protease-resistant kinin analogs 1728, 1729, and 1460 to evaluate their effects on sucrose perception and feeding behavior. In no-choice feeding bioassays (capillary feeder and plate assays), the analog 1728, which contains α-amino isobutyric acid, inhibited females from feeding on sucrose. It further induced quick fly-away or walk-away behavior following contact with the tarsi and the mouthparts. Electrophysiological recordings from single long labellar sensilla of the proboscis demonstrated that mixing the analog 1728 at 1 mM with sucrose almost completely inhibited the detection of sucrose. Aedae-KR was immunolocalized in contact chemosensory neurons in prothoracic tarsi and in sensory neurons and accessory cells of long labellar sensilla in the distal labellum. Silencing Aedae-KR by RNAi significantly reduced gene expression and eliminated the feeding-aversion behavior resulting from contact with the analog 1728, thus directly implicating the Aedae-KR in the aversion response. To our knowledge, this is the first report that kinin analogs modulate sucrose perception in any insect. The aversion to feeding elicited by analog 1728 suggests that synthetic molecules targeting the mosquito Aedae-KR in the labellum and tarsi should be investigated for the potential to discover novel feeding deterrents of mosquito vectors. PMID:27274056

  7. Maya Index and Larva Density Aedes Aegypti Toward Dengue Infection

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    Sang G. Purnama; Tri Baskoro

    2012-01-01

    South Denpasar District was of there as with the highest dengue cases in Bali province. The number of mosquito breeding places and larvae density become risk factor that influenced the spreading of mosquitoes. Maya index was an indicator to measure the amount of waterreservoirs can be breeding places for mosquitoes. Knowing the relationship between maya index and density of larvae and pupae of Ae.aegypti toward dengue infection in South Denpasar District. The study was observational analytic ...

  8. Costs of Three Wolbachia Infections on the Survival of Aedes aegypti Larvae under Starvation Conditions.

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    Perran A Ross

    2016-01-01

    Full Text Available The mosquito Aedes aegypti, the principal vector of dengue virus, has recently been infected experimentally with Wolbachia: intracellular bacteria that possess potential as dengue biological control agents. Wolbachia depend on their hosts for nutrients they are unable to synthesize themselves. Consequently, competition between Wolbachia and their host for resources could reduce host fitness under the competitive conditions commonly experienced by larvae of Ae. aegypti in the field, hampering the invasion of Wolbachia into natural mosquito populations. We assess the survival and development of Ae. aegypti larvae under starvation conditions when infected with each of three experimentally-generated Wolbachia strains: wMel, wMelPop and wAlbB, and compare their fitness to wild-type uninfected larvae. We find that all three Wolbachia infections reduce the survival of larvae relative to those that are uninfected, and the severity of the effect is concordant with previously characterized fitness costs to other life stages. We also investigate the ability of larvae to recover from extended food deprivation and find no effect of Wolbachia on this trait. Aedes aegypti larvae of all infection types were able to resume their development after one month of no food, pupate rapidly, emerge at a large size, and exhibit complete cytoplasmic incompatibility and maternal transmission. A lowered ability of Wolbachia-infected larvae to survive under starvation conditions will increase the threshold infection frequency required for Wolbachia to establish in highly competitive natural Ae. aegypti populations and will also reduce the speed of invasion. This study also provides insights into survival strategies of larvae when developing in stressful environments.

  9. Germ band retraction as a landmark in glucose metabolism during Aedes aegypti embryogenesis

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    Logullo Carlos

    2010-02-01

    Full Text Available Abstract Background The mosquito A. aegypti is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of A. aegypty life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during A. aegypti embryogenesis are unknown. Results Glucose metabolism was investigated throughout Aedes aegypti (Diptera embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE and germ band retraction (GBr, 24 HAE may be considered landmarks regarding glucose 6-phosphate (G6P destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP, of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK and pyruvate kinase (PK activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3 activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis. Conclusions The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose

  10. Fitness evaluation of two Brazilian Aedes aegypti field populations with distinct levels of resistance to the organophosphate temephos

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    Thiago Affonso Belinato

    2012-11-01

    Full Text Available In Brazil, decades of dengue vector control using organophosphates and pyrethroids have led to dissemination of resistance. Although these insecticides have been employed for decades against Aedes aegypti in the country, knowledge of the impact of temephos resistance on vector viability is limited. We evaluated several fitness parameters in two Brazilian Ae. aegypti populations, both classified as deltamethrin resistant but with distinct resistant ratios (RR for temephos. The insecticide-susceptible Rockefeller strain was used as an experimental control. The population presenting the higher temephos resistance level, Aparecida de Goiânia, state of Goiás (RR95 of 19.2, exhibited deficiency in the following four parameters: blood meal acceptance, amount of ingested blood, number of eggs and frequency of inseminated females. Mosquitoes from Boa Vista, state of Roraima, the population with lower temephos resistance level (RR95 of 7.4, presented impairment in only two parameters, blood meal acceptance and frequency of inseminated females. These results indicate that the overall fitness handicap was proportional to temephos resistance levels. However, it is unlikely that these disabilities can be attributed solely to temephos resistance, since both populations are also resistant to deltamethrin and harbour the kdr allele, which indicates resistance to pyrethroids. The effects of reduced fitness in resistant populations are discussed.

  11. UJI REPELEN (DAYA TOLAK BEBERAPA EKSTRAK TUMBUHAN TERHADAP GIGITAN NYAMUK Aedes aegypti VEKTOR DEMAM BERDARAH DENGUE

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    Hasan Boesri Boesri

    2015-10-01

    Full Text Available AbstrakPenyakit­ Demam ­Berdarah ­Dengue,­Malaria,­filaria­sejauh­ini­masih­menjadi­masalah­kesehatan­masyarakat.Penggunaan insektisida nabati banyak memberikan keuntungan diantaranya ramah lingkungan, tidak memberikan dampak buruk pada kesehatan dan bahan dasar ada di sekitar pemukiman. Berdasarkan banyaknya keuntungan yang didapatkan, maka dipandang perlu untuk mencari insektisida nabati sebagai repelen untuk  menolak gigitan nyamuk  penular penyakit. Penelitian ini merupakan eksperimen murni, tentang pembuatan ekstrak dari berbagai­bahan­tanaman­serta­uji­efektifitas­daya­tolak­nyamuknya­dan­dilakukan­di­laboratorium.­Pembuatanekstrak dilakukan di Laboratorium Farmasi Universitas Gajah Mada Yogyakarta, sedangkan  untuk pengujian ekstrak terhadap nyamuk Aedes aegypti dilakukan di laboratorium uji insektisida Balai Besar Litbang Vektor dan Reservoir Penyakit. Hasil penelitian uji  repelen beberapa ekstrak tumbuhan adalah pada dosis 100%  yang mampu menolak gigitan nyamuk di atas 80% per jam  antara lain ekstrak daun Zodia mampu menolak sampai 2 jam sebanyak 88,2%. Ekstrak daun tembakau  mampu menolak  selama 3 jam sebanyak  84,9%, ekstrak daun gondopuro mampu menolak selama 1 jam sebanyak  83,3%,  ekstrak daun Serai Wangi mampu menolak selama 2 jam sebanyak 85,1%. Ekstrak daun cengkeh mampu menolak selama 4 jam sebanyak, 81,7%. Ekstrak bunga krisan mampu menolak selama 1 jam sebanyak 89,6%, Sedangkan ekstrak daun suren, akar tuba dan lavender hanya mampu menolak gigitan nyamuk Aedes aegypti di bawah 80%.Kata kunci : ekstrak, repelen, Aedes aegyptiAbstractDengue­Haemorrhagic­Fever,­malaria,­filaria­so­far­are­public­health­problem.­The­use­of­plant-based­­insecticidesare­many­eco-friendly­benefits,­do­not­give­bad­impact­on­­health­and­basic­materials­are­all­around­settlements.­Itis necessary to look for botanical insecticides as repellent to resist bites mosquito

  12. UDP-N-Acetyl glucosamine pyrophosphorylase as novel target for controlling Aedes aegypti – molecular modeling, docking and simulation studies

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    Bhagath Kumar Palaka

    2014-12-01

    Full Text Available Aedes aegypti is a vector that transmits diseases like dengue fever, chikungunya, and yellow fever. It is distributed in all tropical and subtropical regions of the world. According to WHO reports, 40% of the world’s population is currently at risk for dengue fever. As vaccines are not available for such diseases, controlling mosquito population becomes necessary. Hence, this study aims at UDP-N-acetyl glucosamine pyrophosphorylase of Aedes aegypti (AaUAP, an essential enzyme for chitin metabolim in insects, as a drug target. Structure of AaUAP was predicted and validated using in-silico approach. Further, docking studies were performed using a set of 10 inhibitors out of which NAG9 was found to have good docking score, which was further supported by simulation studies. Hence, we propose that NAG9 can be considered as a potential hit in designing new inhibitors to control Aedes aegypti.

  13. Weather Variability Associated with Aedes (Stegomyia) aegypti (Dengue Vector) Oviposition Dynamics in Northwestern Argentina.

    Science.gov (United States)

    Estallo, Elizabet L; Ludueña-Almeida, Francisco F; Introini, María V; Zaidenberg, Mario; Almirón, Walter R

    2015-01-01

    This study aims to develop a forecasting model by assessing the weather variability associated with seasonal fluctuation of Aedes aegypti oviposition dynamic at a city level in Orán, in northwestern Argentina. Oviposition dynamics were assessed by weekly monitoring of 90 ovitraps in the urban area during 2005-2007. Correlations were performed between the number of eggs collected weekly and weather variables (rainfall, photoperiod, vapor pressure of water, temperature, and relative humidity) with and without time lags (1 to 6 weeks). A stepwise multiple linear regression analysis was performed with the set of meteorological variables from the first year of study with the variables in the time lags that best correlated with the oviposition. Model validation was conducted using the data from the second year of study (October 2006- 2007). Minimum temperature and rainfall were the most important variables. No eggs were found at temperatures below 10 °C. The most significant time lags were 3 weeks for minimum temperature and rains, 3 weeks for water vapor pressure, and 6 weeks for maximum temperature. Aedes aegypti could be expected in Orán three weeks after rains with adequate min temperatures. The best-fit forecasting model for the combined meteorological variables explained 70 % of the variance (adj. R(2)). The correlation between Ae. aegypti oviposition observed and estimated by the forecasting model resulted in rs = 0.80 (P vector activity can be predicted three or four weeks in advance. PMID:25993415

  14. Heritable CRISPR/Cas9-mediated genome editing in the yellow fever mosquito, Aedes aegypti.

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    Shengzhang Dong

    Full Text Available In vivo targeted gene disruption is a powerful tool to study gene function. Thus far, two tools for genome editing in Aedes aegypti have been applied, zinc-finger nucleases (ZFN and transcription activator-like effector nucleases (TALEN. As a promising alternative to ZFN and TALEN, which are difficult to produce and validate using standard molecular biological techniques, the clustered regularly interspaced short palindromic repeats/CRISPR-associated sequence 9 (CRISPR/Cas9 system has recently been discovered as a "do-it-yourself" genome editing tool. Here, we describe the use of CRISPR/Cas9 in the mosquito vector, Aedes aegypti. In a transgenic mosquito line expressing both Dsred and enhanced cyan fluorescent protein (ECFP from the eye tissue-specific 3xP3 promoter in separated but tightly linked expression cassettes, we targeted the ECFP nucleotide sequence for disruption. When supplying the Cas9 enzyme and two sgRNAs targeting different regions of the ECFP gene as in vitro transcribed mRNAs for germline transformation, we recovered four different G1 pools (5.5% knockout efficiency where individuals still expressed DsRed but no longer ECFP. PCR amplification, cloning, and sequencing of PCR amplicons revealed indels in the ECFP target gene ranging from 2-27 nucleotides. These results show for the first time that CRISPR/Cas9 mediated gene editing is achievable in Ae. aegypti, paving the way for further functional genomics related studies in this mosquito species.

  15. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

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    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.

  16. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

    Directory of Open Access Journals (Sweden)

    Stein Marina

    2002-01-01

    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.

  17. Larvicidal efficacy screening of Anacardaciae crude extracts on the dengue hemorrhagic vector, Aedes aegypti.

    Science.gov (United States)

    Zuharah, W F; Fadzly, N; Ali, Y; Zakaria, R; Juperi, S; Asyraf, M; Dieng, H

    2014-06-01

    Vector-borne diseases are still rife because of the re-emergence of diseases transmitted by mosquitoes. The objective of this paper is to evaluate the larvicidal efficacy of crude leaf extract of Mangifera indica, Gluta renghas, and Melanochyla fasciculiflora against vector of dengue hemorrhagic fever, Aedes aegypti. These plant species are endemic species and widely distributed in Malaysian forests. Leaves of Ma. indica, G. renghas and M. fascculiflora were collected from Teluk Bahang National Park, Penang Malaysia. Fractions of leaves were segregated, air-dried, powdered and extracted using Soxhlet with methanol. The solvent was removed by using rotary evaporator to obtain the crude extract. Using WHO standard larval bioassay test method, third instar larvae of Aedes aegypti were exposed to concentration ranging from 200- 4500 ppm of methanol extract for all plant species. Larval mortality was observed after 24 hours exposure. The highest susceptibility and toxicity was recorded by Mangifera indica with the lowest concentration at 800 ppm followed by M. fasciculiflora and G. renghas. This indicates that crude plant extract is very effective in killing Ae. aegypti mosquitoes. This finding may lead to new low cost alternative, environmentally friendly method for mosquito control programs. To our knowledge, this is the first report on larvicidal bioefficacy from endemic Malaysian plants. PMID:25134898

  18. Towards a Casa Segura: a consumer product study of the effect of insecticide-treated curtains on Aedes aegypti and dengue virus infections in the home.

    Science.gov (United States)

    Loroño-Pino, María Alba; García-Rejón, Julián E; Machain-Williams, Carlos; Gomez-Carro, Salvador; Nuñez-Ayala, Guadalupe; Nájera-Vázquez, Maria del Rosario; Losoya, Arturo; Aguilar, Lyla; Saavedra-Rodriguez, Karla; Lozano-Fuentes, Saul; Beaty, Meaghan K; Black, William C; Keefe, Thomas J; Eisen, Lars; Beaty, Barry J

    2013-08-01

    The home, or domicile, is the principal environment for transmission of dengue virus (DENV) between humans and mosquito vectors. Community-wide distribution of insecticide-treated curtains (ITCs), mimicking vector control program-driven interventions, has shown promise to reduce DENV infections. We conducted a Casa Segura consumer product intervention study in Mérida, Mexico to determine the potential to reduce intradomicillary DENV transmission through ITC use in individual homes. Dengue virus infections in mosquitoes and in humans were reduced in homes with ITCs in one of two study subareas. Overall, ITCs reduced intradomicillary DENV transmission; ITC homes were significantly less likely to experience multiple DENV infections in humans than NTC homes. Dengue virus-infected Aedes aegypti females were reduced within the ITC homes where curtain use was highest. Some homes yielded up to nine infected Ae. aegypti females. This study provides insights regarding best practices for Casa Segura interventions to protect homes from intradomicillary DENV transmission.

  19. A secure semi-field system for the study of Aedes aegypti.

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    Scott A Ritchie

    inside to outside of the insectary, and screened (0.25 mm mesh drains within the insectary and the cage. A set of standard operating procedures (SOP has been developed to ensure that security is maintained and for enhanced surveillance for escaping mosquitoes on the JCU campus where the MRF is located. A cohort of male and female Aedes aegypti mosquitoes were released in the cage and sampled every 3-4 days to determine daily survival within the cage; log linear regression from BG-sentinel trapping collections produced an estimated daily survival of 0.93 and 0.78 for females and males, respectively. CONCLUSIONS/SIGNIFICANCE: The MRF SFS allows us to test novel control strategies within a secure, contained environment. The air-conditioning system maintains conditions within the MRF cages comparable to outside ambient conditions. This cage provides a realistic transitional platform between the laboratory and the field in which to test novel control measures on quarantine level insects.

  20. Analisis Fakto - Faktor Densitas Larva Aedes aegypti dan Endimisitas Penyakit Demam Berdarah Dengue di Kabupaten Bulukumba, Sulawasi Selatan

    OpenAIRE

    Hasanuddin, ishak; Abbas; arsin, arsunan

    2008-01-01

    Penyakit Demam Berdarah Dengue (DBD) masih merupakan masalah kesehatan masyarakat di Indonesia. Upaya gerakan 3M, abatisasi dan fogging sudah dilakukan namun densitas Aedes aegypti masih tinggi dan daerah endemism akin meluas. Penelitian ini bertujuan untuk menganalisis faktor ??? faktor yang berhubungan dengan densitas larva A. aegypti dan endemisitas Penyakit Demam Berdarah Dengue. Desain penelitian ini menggunakan cross sectional study dan dilaksanakan di 4 kelurahan endemis di Kecamatan U...

  1. Larvicidal and repellent effect of some Tribulus terrestris L., (Zygophyllaceae) extracts against the dengue fever mosquito, Aedes aegypti (Diptera: Culicidae)

    OpenAIRE

    Tarek M.Y. El-Sheikh; Zarrag I.A. Al-Fifi; Mohamed A. Alabboud

    2016-01-01

    Aedes aegypti transmits etiologic agents of yellow fever and dengue. Vaccine for dengue virus is not available and vector control is essential to minimize dengue incidence. The larvicidal and repellent effect of the crude ethanol, acetone and petroleum ether extract leaves of Tribulus terrestris, against 3rd instar larvae and adults of mosquito, Ae. aegypti the vector of dengue fever was evaluated. The efficacy of petroleum ether extract seemed to be more effective with LC50 64.6 ppm followed...

  2. Field Efficacy of New Larvicide Products for Control of Multi-Resistant Aedes aegypti Populations in Martinique (French West Indies)

    OpenAIRE

    Marcombe, Sébastien; Darriet, Frédéric; Agnew, Philip; Etienne, Manuel; Yp-Tcha, Marie-Michelle; Yébakima, André; Corbel, Vincent

    2011-01-01

    World-wide dengue vector control is hampered by the spread of insecticide resistance in Aedes aegypti. We report the resistance status of a wild Ae. aegypti population from Martinique (Vauclin) to conventional larvicides (Bacillus thuringiensis var israeliensis [Bti] and temephos) and potential alternatives (spinosad, diflubenzuron, and pyriproxyfen). The efficacy and residual activity of these insecticides were evaluated under simulated and field conditions. The Vauclin strain exhibited a hi...

  3. Fitness evaluation of two Brazilian Aedes aegypti field populations with distinct levels of resistance to the organophosphate temephos

    OpenAIRE

    Thiago Affonso Belinato; Ademir Jesus Martins; Denise Valle

    2012-01-01

    In Brazil, decades of dengue vector control using organophosphates and pyrethroids have led to dissemination of resistance. Although these insecticides have been employed for decades against Aedes aegypti in the country, knowledge of the impact of temephos resistance on vector viability is limited. We evaluated several fitness parameters in two Brazilian Ae. aegypti populations, both classified as deltamethrin resistant but with distinct resistant ratios (RR) for temephos. The insecticide-sus...

  4. Expression Profile of Genes during Resistance Reversal in a Temephos Selected Strain of the Dengue Vector, Aedes aegypti

    OpenAIRE

    Clare Strode; Maria de Melo-Santos; Tereza Magalhães; Ana Araújo; Contancia Ayres

    2012-01-01

    BACKGROUND: The mosquito Aedes aegypti is one of the most important disease vectors because it transmits two major arboviruses, dengue and yellow fever, which cause significant global morbidity and mortality. Chemical insecticides form the cornerstone of vector control. The organophosphate temephos a larvicide recommended by WHO for controlling Ae. aegypti, however, resistance to this compound has been reported in many countries, including Brazil. METHODOLOGY/PRINCIPAL FINDINGS: The aim of th...

  5. The efficacy of a chitin synthesis inhibitor against field populations of organophosphate-resistant Aedes aegypti in Brazil

    OpenAIRE

    Nathalia Giglio Fontoura; Diogo Fernandes Bellinato; Denise Valle; José Bento Pereira Lima

    2012-01-01

    The mosquito Aedes aegypti is the main focus of dengue control campaigns. Because of widespread resistance against conventional chemical insecticides, chitin synthesis inhibitors (CSIs) are considered control alternatives. We evaluated the resistance status of four Brazilian Ae. aegypti populations to both the organophosphate temephos and the pyrethroid deltamethrin, which are used in Brazil to control larvae and adults, respectively. All vector populations exhibited high levels of temephos r...

  6. The susceptibility of Aedes aegypti populations displaying temephos resistance to Bacillus thuringiensis israelensis: a basis for management

    OpenAIRE

    Araújo, Ana Paula; Araujo Diniz, Diego Felipe; Helvecio, Elisama; de Barros, Rosineide Arruda; de Oliveira, Cláudia Maria Fontes; Ayres, Constância Flávia Junqueira; de Melo-Santos, Maria Alice Varjal; Regis, Lêda Narcisa; Silva-Filha, Maria Helena Neves Lobo

    2013-01-01

    Background Aedes aegypti is the vector of dengue virus, and its control is essential to prevent disease transmission. Among the agents available to control this species, biolarvicides based on Bacillus thuringiensis serovar israelensis (Bti) are an effective alternative to replace the organophosphate temephos for controlling populations that display resistance to this insecticide. The major goal of this study was to determine the baseline susceptibility of Brazilian Ae. aegypti populations to...

  7. Molecular characterization of Aedes aegypti (L.) (Diptera: Culicidae) of Easter Island based on analysis of the mitochondrial ND4 gene

    OpenAIRE

    Claudia Andrea Núñez; Christian Raúl González; Víctor Obreque; Brenda Riquelme; Carolina Reyes; Mabel Rojas

    2016-01-01

    ABSTRACT Aedes aegypti mosquitoes are the main vector of viruses Dengue, Zika and Chikungunya. Shortly after the first report of the dengue vector Ae. aegypti in Easter Island (Rapa Nui) in late 2000, the first disease outbreak dengue occurred. Viral serotyping during the 2002 outbreak revealed a close relationship with Pacific DENV-1 genotype IV viruses, supporting the idea that the virus most likely originated in Tahiti. Mitochondrial NADH dehydrogenase subunit 4 (ND4) DNA sequences generat...

  8. Permethrin-treated clothing as protection against the Dengue vector, Aedes aegypti : extent and duration of protection.

    OpenAIRE

    Sarah DeRaedt Banks; James Orsborne; Salvador A. Gezan; Harparkash Kaur; Annelies Wilder-Smith; Lindsey, Steve W.; Logan, James G

    2015-01-01

    INTRODUCTION: Dengue transmission by the mosquito vector, Aedes aegypti, occurs indoors and outdoors during the day. Personal protection of individuals, particularly when outside, is challenging. Here we assess the efficacy and durability of different types of insecticide-treated clothing on laboratory-reared Ae. aegypti. METHODS: Standardised World Health Organisation Pesticide Evaluation Scheme (WHOPES) cone tests and arm-in-cage assays were used to assess knockdown (KD) and mortality of Ae...

  9. 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

  10. VECTOR RESISTANCE STATUS OF DENGUE HEMORRHAGIC FEVER (Aedes aegypti IN THE SIDOREJO DISTRICT SALATIGA CITY AGAINST TEMEPHOS (ORGANOPHOSPHATES

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    Ary Oktsari Yanti S

    2014-06-01

    Full Text Available One of the efforts to control the incidence of Dengue Hemorrhagic Fever (DHF is contrled thedengue vector larvae using larvasida. The most widely larvasida used to control larvae Ae.aegypti is temephos. In Indonesia 1% temephos (abate 1SG has been used since 1976, and since1980 has been used for the eradication program ofAe. aegypti larvae. The purpose of this studyis to determine the resistance status of vectors of dengue hemorrhagic fever (Ae. aegypti ofendemic, sporadic, and potentially in Sub District Sidorejo Salatiga City to temephos(organofosfat. This research was conducted using experimental research design (TrueExperiment, posttcst design with control groups (posttest-only Control Group Design. Thepopulation of the research were larvae of Ae. aegypti collected from the study area. Samples testlarvae were used of Ae. aegypti third and early fourth instars larvae which were maintenance ofthe first generation. The result showed that the mortality percentages of Ae. aegypti larvaeof endemic, sporadic and potential administratives against temephos using WHO standardconcentration (0,625; 0,125; 0,025 mg/1 indicates the mortality of Ae. aegypti larvae by 100%Based on the status resistance criteria, Ae. aegypti larvae from endemic, sporadic, and potentialadministratives of Sidorejo Sub-District, Salatiga City is still susceptible to temephos.Keywords : Status of resistance, Aedes aegypti. TemephosSalah satu upaya menurunkan Demam Berdarah Dengue (DBD adalah melaluipengcndalian jentik vektor DBD dengan larvasida. Larvasida yang digunakan untukmengcndalikan jentik Ae. aegypti adalah temephos. Temephos 1% (abate ISG sudah programdi Indonesia sejak 1976, scjak 1980 telah digunakan secara massal untuk programpemberantasan jentik Ae. aegypti. Tujuan penelitian ini adalah untuk mengetahui status resistensivektor demam berdarah dengue Ae. aegypti di kclurahan endemis, sporadis, dan potensialKecamatan Sidorejo Kota Salatiga terhadap temephos

  11. Synthesis and biological activity of acetates of copper (II and iron (III for the control of Aedes aegypti (Diptera: Culicidae

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    Jéssica V. Nardeli

    2012-06-01

    Full Text Available This work aimed to the synthesis of basic acetates of Cu (II and Fe(III against larvae of Aedes aegypti and Gram negative and Gram positive. The transition metal ions Cu (II and Fe (III have bactericidal activity and are toxic to Aedes aegypti larvae in the eggs and larval stages of initial, precludes the eggs hatch and slow reproductive cycle of the insect. The theme investigates the importance of carboxyl groups in complex formation, transport and cellular internalization of the toxic ions. It is known that the bactericide or insecticide activity is due to metal ions and Cu (IIor Fe (III.

  12. Aspectos bioecológicos de importancia para el control de Aedes aegypti y otros culicidos en el ecosistema urbano

    OpenAIRE

    Marquetti Fernández, María del Carmen

    2007-01-01

    Conocer la influencia del Programa de Erradicación de Aedes aegypti en la incidencia, y abundancia de culícidos incluyendo el vector del dengue en el ecosistema urbano es de importancia ya que las enfermedades transmitidas por estos constituyen problemas prioritarios de salud en Cuba. El presente trabajo aporta conocimientos novedosos con relación a la bioecologia de Aedes aegypti y otros culícidos, como Culex quinquefasciatus y Gymnometopa mediovittata, así como la caracterización de los háb...

  13. Embryonic desiccation resistance in Aedes aegypti: presumptive role of the chitinized Serosal Cuticle

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    Peixoto Alexandre

    2008-09-01

    Full Text Available Abstract Background One of the major problems concerning dengue transmission is that embryos of its main vector, the mosquito Aedes aegypti, resist desiccation, surviving several months under dry conditions. The serosal cuticle (SC contributes to mosquito egg desiccation resistance, but the kinetics of SC secretion during embryogenesis is unknown. It has been argued that mosquito SC contains chitin as one of its components, however conclusive evidence is still missing. Results We observed an abrupt acquisition of desiccation resistance during Ae. aegypti embryogenesis associated with serosal cuticle secretion, occurring at complete germ band extension, between 11 and 13 hours after egglaying. After SC formation embryos are viable on dry for at least several days. The presence of chitin as one of the SC constituents was confirmed through Calcofluor and WGA labeling and chitin quantitation. The Ae. aegypti Chitin Synthase A gene (AaCHS1 possesses two alternatively spliced variants, AaCHS1a and AaCHS1b, differentially expressed during Ae. aegypti embryonic development. It was verified that at the moment of serosal cuticle formation, AaCHS1a is the sole variant specifically expressed. Conclusion In addition to the peritrophic matrix and exoskeleton, these findings confirm chitin is also present in the mosquito serosal cuticle. They also point to the role of the chitinized SC in the desiccation resistance of Ae. aegypti eggs. AaCHS1a expression would be responsible for SC chitin synthesis. With this embryological approach we expect to shed new light regarding this important physiological process related to the Ae. aegypti life cycle.

  14. Human-Mediated Marine Dispersal Influences the Population Structure of Aedes aegypti in the Philippine Archipelago.

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    Eugenio Fonzi

    Full Text Available Dengue virus (DENV is an extraordinary health burden on global scale, but still lacks effective vaccine. The Philippines is endemic for dengue fever, but massive employment of insecticides favored the development of resistance mutations in its major vector, Aedes aegypti. Alternative vector control strategies consist in releasing artificially modified mosquitos in the wild, but knowledge on their dispersal ability is necessary for a successful implementation. Despite being documented that Ae. aegypti can be passively transported for long distances, no study to date has been aimed at understanding whether human marine transportation can substantially shape the migration patterns of this mosquito. With thousands of islands connected by a dense network of ships, the Philippines is an ideal environment to fill this knowledge gap.Larvae of Ae. aegypti from 15 seaports in seven major islands of central-western Philippines were collected and genotyped at seven microsatellite loci. Low genetic structure and considerable gene flow was found in the area. Univariate and multivariate regression analyses suggested that anthropic factors (specifically the amount of processed cargo and human population density can explain the observed population structure, while geographical distance was not correlated. Interestingly, cargo shipments seem to be more efficient than passenger ships in transporting Ae. aegypti. Bayesian clustering confirmed that Ae. aegypti from busy ports are more genetically similar, while populations from idle ports are relatively structured, regardless of the geographical distance that separates them.The results confirmed the pivotal role of marine human-mediated long-range dispersal in determining the population structure of Ae. aegypti. Hopefully corroborated by further research, the present findings could assist the design of more effective vector control strategies.

  15. Vector competence of Aedes aegypti and Aedes vittatus (Diptera: Culicidae) from Senegal and Cape Verde archipelago for West African lineages of chikungunya virus.

    Science.gov (United States)

    Diagne, Cheikh T; Faye, Oumar; Guerbois, Mathilde; Knight, Rachel; Diallo, Diawo; Faye, Ousmane; Ba, Yamar; Dia, Ibrahima; Faye, Ousmane; Weaver, Scott C; Sall, Amadou A; Diallo, Mawlouth

    2014-09-01

    To assess the risk of emergence of chikungunya virus (CHIKV) in West Africa, vector competence of wild-type, urban, and non-urban Aedes aegypti and Ae. vittatus from Senegal and Cape Verde for CHIKV was investigated. Mosquitoes were fed orally with CHIKV isolates from mosquitoes (ArD30237), bats (CS13-288), and humans (HD180738). After 5, 10, and 15 days of incubation following an infectious blood meal, presence of CHIKV RNA was determined in bodies, legs/wings, and saliva using real-time reverse transcription-polymerase chain reaction. Aedes vittatus showed high susceptibility (50-100%) and early dissemination and transmission of all CHIKV strains tested. Aedes aegypti exhibited infection rates ranging from 0% to 50%. Aedes aegypti from Cape Verde and Kedougou, but not those from Dakar, showed the potential to transmit CHIKV in saliva. Analysis of biology and competence showed relatively high infective survival rates for Ae. vittatus and Ae. aegypti from Cape Verde, suggesting their efficient vector capacity in West Africa. PMID:25002293

  16. Chemical constituents of the stems of Spathelia excelsa (rutaceae) and activity against Aedes aegypti; Constituintes quimicos do caule de Spathelia excelsa (rutaceae) e atividade contra Aedes aegypti

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    Freitas, Aline Carvalho de; Lima, Maria da Paz [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Produtos Naturais], e-mail: mdapaz@inpa.gov.br; Ferreira, Antonio Gilberto [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Tadei, Wanderli Pedro; Pinto, Ana Cristina da Silva [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Lab. de Vetores de Malaria e Dengue

    2009-07-01

    Phytochemical investigation from the stems of Spathelia excelsa (Rutaceae) collected in Amazonas yielded deacetylspathelin (1), 7,8-dimethoxyflindersine (2), new glabretal-type triterpenoid 3{beta}-angeloyl-21,24-epoxy-7{alpha}, 21{alpha}, 23{alpha}, 25-tetrahydroxy-4{alpha}, 4{beta}, 8{beta}, 10{beta}-tetramethyl-25-dimethyl-14,18-cyclo-5{alpha}, 13{alpha}, 14{alpha}, 17{alpha}-cholestane (3), in addition to the known steroids s-sitosterol and stigmasterol. Their structures were established on the basis of spectral data. The compounds 1 and 3 were assayed on Aedes aegypti (larvicidal and adulticidal activities and compound 3 exhibited larvicidal properties with LC{sub 50} of 4,8 {mu}g/mL. (author)

  17. Experimental Infection of Culex (Culex quinquefasciatus and Aedes (Stegomyia aegypti with Wuchereria bancrofti

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    Calheiros Cláudia ML

    1998-01-01

    Full Text Available A study was conducted to determine the susceptibility of local strains of Culex quinquefasciatus and Aedes aegypti to infection with the strain of Wuchereria bancrofti that occurs in Maceió, State of Alagoas, Brazil. Cx. quinquefasciatus blood fed simultaneously on the same microfilariae carrier ingested more blood and 2-3x more microfilariae than Ae. aegypti. Survival rates of both species of insects living for 21 days after blood feeding on microfilaraemic patients were not significantly different from the survival rates of mosquitoes that blood fed on amicrofilaraemic individuals. W. bancrofti parasites underwent normal development in Cx. quinquefasciatus, with third stage larvae first being recorded on the 11th day post infection, and their numbers increasing thereafter. Development of filariae in Ae. aegypti did not proceed beyond the first larval stage, and there was a progressively increasing number of non-viable larvae with the passage of time. It is concluded that Ae. aegypti is not involved in the transmission of W. bancrofti in Maceió.

  18. TALEN-based gene disruption in the dengue vector Aedes aegypti.

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    Azadeh Aryan

    Full Text Available In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20-40% of fertile survivors produced kmo alleles that failed to complement an existing kh(w mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1-7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector.

  19. Semaphorin-1a is required for Aedes aegypti embryonic nerve cord development.

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    Morgan Haugen

    Full Text Available Although mosquito genome projects have uncovered orthologues of many known developmental regulatory genes, extremely little is known about mosquito development. In this study, the role of semaphorin-1a (sema1a was investigated during vector mosquito embryonic ventral nerve cord development. Expression of sema1a and the plexin A (plexA receptor are detected in the embryonic ventral nerve cords of Aedes aegypti (dengue vector and Anopheles gambiae (malaria vector, suggesting that Sema1a signaling may regulate mosquito nervous system development. Analysis of sema1a function was investigated through siRNA-mediated knockdown in A. aegypti embryos. Knockdown of sema1a during A. aegypti development results in a number of nerve cord phenotypes, including thinning, breakage, and occasional fusion of the longitudinal connectives, thin or absent commissures, and general distortion of the nerve cord. Although analysis of Drosophila melanogaster sema1a loss-of-function mutants uncovered many similar phenotypes, aspects of the longitudinal phenotypes differed between D. melanogaster and A. aegypti. The results of this investigation suggest that Sema1a is required for development of the insect ventral nerve cord, but that the developmental roles of this guidance molecule have diverged in dipteran insects.

  20. Larvicidal activity of some Euphorbiaceae plant extracts against Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Rahuman, A Abdul; Gopalakrishnan, Geetha; Venkatesan, P; Geetha, Kannappan

    2008-04-01

    Larvicidal activity of ethyl acetate, butanol, and petroleum ether extracts of five species of Euphorbiaceae plants, Jatropha curcas, Pedilanthus tithymaloides, Phyllanthus amarus, Euphorbia hirta, and Euphorbia tirucalli, were tested against the early fourth instar larvae of Aedes aegypti L. and Culex quinquefasciatus (Say). The larval mortality was observed after 24 h of exposure. All extracts showed low larvicidal effects; however, the highest larval mortality was found in petroleum ether extract. The LC50 value of petroleum ether extracts of J. curcas, P. tithymaloides, P. amarus, E. hirta, and E. tirucalli were 8.79, 55.26, 90.92, 272.36, and 4.25 ppm, respectively, against A. aegypti and 11.34, 76.61, 113.40, 424.94, and 5.52 ppm, respectively, against C quinquefasciatus. Of the various ratios tested, the petroleum ether extracts of J. curcas and E. tirucalli were observed to be more efficient than the other plant extracts. It is, therefore, suggested that E. tirucalli can be applied as an ideal potential larvicide against A. aegypti and C. quinquefasciatus. This is an ideal ecofriendly approach for the control of the dengue vector, A. aegypti, and the lymphatic filariasis vector, C. quinquefasciatus.

  1. Lethal ovitrap deployment for Aedes aegypti control: potential implications for non-target organisms.

    Science.gov (United States)

    Long, Sharron A; Jacups, Susan P; Ritchie, Scott A

    2015-06-01

    In Australia, dengue control combines source reduction with lethal ovitraps to reduce Aedes aegypti populations during outbreaks. Lethal ovitraps are considered a sustainable and environmentally friendly method of controlling container-inhabiting mosquitoes, however, to-date, this claim has not been quantified. This study assesses the potential impact of lethal ovitraps on non-target organisms when used to control Ae. aegypti in tropical Australia. For retention of specimens, we substituted standard sticky ovitraps for lethal ovitraps. We collected 988 Ae. aegypti and 44,132 non-target specimens over 13 months from 16 sites. Although Ae. aegypti comprised only 2.2% of the total collection, they were were the eighth most dominant taxa collected, on the 93(rd) percentile. Of the non-target organisms, Collembola were the dominant taxa, 44.2%, with 36.8% and 10.5% Diptera and Hymenoptera, respectively. Of the Dipterans, 61% were family Phoridae. Lethal ovitraps were visited by 90 insect or invertebrate families in total. Ovitraps are attractive to Collembola, Phoridae, Sciaridae, Formicidae, and Culicidae, with minimal attraction by Apidae and other commonly monitored non-target organisms. For container-inhabiting mosquitoes, LOs are cost effective operationally, requiring minimal staff resources for placement and retrieval.

  2. Multiple Modes of Action of the Squamocin in the Midgut Cells of Aedes aegypti Larvae

    Science.gov (United States)

    de Paula, Sérgio Oliveira; Martins, Gustavo Ferreira; Zanuncio, José Cola

    2016-01-01

    Annonaceous acetogenins are botanical compounds with good potential for use as insecticides. In the vector, Aedes aegypti (L.) (Diptera: Culicidae), squamocin (acetogenin) has been reported to be a larvicide and cytotoxic, but the modes of action of this molecule are still poorly understood. This study evaluated the changes in the cell morphology, and in the expression of genes, for autophagy (Atg1 and Atg8), for membrane ion transporter V-ATPase, and for water channel aquaporin-4 (Aqp4) in the midgut of A. aegypti larvae exposed to squamocin from Annona mucosa Jacq. (Annonaceae). Squamocin showed cytotoxic action with changes in the midgut epithelium and digestive cells of A. aegypti larvae, increase in the expression for autophagy gene Atg1 and Atg8, decrease in the expression of V-ATPase, decrease in the expression of Aqp4 gene in LC20 and inhibition of Apq4 genes in the midgut of this vector in LC50. These multiple modes of action for squamocin are described for the first time in insects, and they are important because different sites of action of squamocin from A. mucosa may reduce the possibility of resistance of A. aegypti to this molecule. PMID:27532504

  3. STUDIES ON AEDES AEGYPTI RESISTANCE TO SOME INSECTICIDES IN THE JAZAN DISTRICT, SAUDI ARABIA.

    Science.gov (United States)

    Alsheikh, Adel A; Mohammed, W S; Noureldin, E M; Daffalla, O M; Shrwani, Y A; Hobani, K J; Alsheikh, F A; Alzahrani, M H; Binsaeed, A A

    2016-04-01

    The present study provided information on the susceptibility status of the adult and larvae of Aedes aegypti mosquitoes in Jazan region of Saudi Arabia. Bioassay tests were performed on adults and larvae by using WHO recommended concentrations and test kits. Adults of Ae. aegypti mosquitoes were exposed to test papers impregnated with Lambda-cyhalothrin (0.05%), Cyfluthrin (0.15%), Deltamethrin (0.05%), Permethrin (0.75%), Fenitrothion (1%), Bendiocarb (0.1%) and DDT (4%) insecticides. Ae. aegypti mosquitoes were found to be susceptible only to Cyfluthrin; (mortality rate was 100%), whereas variable resistances were observed from the rest of the other insecticides tested (mortality rates ranged between 93.6 and 17%). Larvae were subjected to different concentrations of Diflubenzuron, Methoprene (IGRs) and Temephos (Organophosphate). Adult emergence inhibition (IE₅₀ & IE₉₅) values for the IGRs and the (LC₅₀ & LC₉₅) for Temephos were determined by log-probit regression analysis. Ae. aegypti larvae were resistant to Temephos (LC₅₀ 61.8-LC₉₅ 35600.1 mg/l) and showed high susceptibility to Methoprene than Diflubenzuron (IE₅₀ 0.49-IE₉₅ 10.9 mg/l) and (IE₅₀ 0.86 and IE₉₅ 93.8 mg/l), respectively. Larvae were more susceptible to Methoprene than Diflubenzuron by 1.8 folds.

  4. Toxicity of Cephalaria Species and their Individual Constituents against Aedes aegypti.

    Science.gov (United States)

    Sarikahya, Nazli Boke; Kayce, Peyker; Tabanca, Nurhayat; Estep, Alden S; Becnel, James J; Khan, Ikhlas A; Kirmizigul, Suheyla

    2015-07-01

    Crude acetone and ethanol extracts of the aerial parts of 21 Cephalaria species collected from Turkey were investigated for larvicidal and adult topical activity against Aedes aegypti. The ethanol extracts from C. elazigensis var. purpurea, C. anatolica, and C. elmaliensis possessed the highest mortality against first instar Ae. aegypti larvae. Luteolin-7-O-β-D-glycoside (1), isolated from C. elmaliensis ethanol extract, demonstrated 33% and 53% mortality at 0.1 μg/mL concentration against first instar ORL (susceptible) and PR (pyrethroid resistant) strains, respectively. C. scoparia acetone extract showed 100% mortality against adult Ae. aegypti. From this extract compounds 2-8 were isolated. Compound 2 (isoorientin) possessed the highest toxicity with 31.7% and 65% mortality at a 10 μg/mL concentration against adult ORL and PR strains, respectively. This is the first screening report of potential insecticides from Cephalaria species against the yellow fever mosquito, Ae. aegypti, and the active compounds (1 and 2) could lead to the development of a new class of insecticide.

  5. Toxicity of Cephalaria Species and their Individual Constituents against Aedes aegypti.

    Science.gov (United States)

    Sarikahya, Nazli Boke; Kayce, Peyker; Tabanca, Nurhayat; Estep, Alden S; Becnel, James J; Khan, Ikhlas A; Kirmizigul, Suheyla

    2015-07-01

    Crude acetone and ethanol extracts of the aerial parts of 21 Cephalaria species collected from Turkey were investigated for larvicidal and adult topical activity against Aedes aegypti. The ethanol extracts from C. elazigensis var. purpurea, C. anatolica, and C. elmaliensis possessed the highest mortality against first instar Ae. aegypti larvae. Luteolin-7-O-β-D-glycoside (1), isolated from C. elmaliensis ethanol extract, demonstrated 33% and 53% mortality at 0.1 μg/mL concentration against first instar ORL (susceptible) and PR (pyrethroid resistant) strains, respectively. C. scoparia acetone extract showed 100% mortality against adult Ae. aegypti. From this extract compounds 2-8 were isolated. Compound 2 (isoorientin) possessed the highest toxicity with 31.7% and 65% mortality at a 10 μg/mL concentration against adult ORL and PR strains, respectively. This is the first screening report of potential insecticides from Cephalaria species against the yellow fever mosquito, Ae. aegypti, and the active compounds (1 and 2) could lead to the development of a new class of insecticide. PMID:26411009

  6. Multiple Modes of Action of the Squamocin in the Midgut Cells of Aedes aegypti Larvae.

    Science.gov (United States)

    da Silva Costa, Marilza; de Paula, Sérgio Oliveira; Martins, Gustavo Ferreira; Zanuncio, José Cola; Santana, Antônio Euzébio Goulart; Serrão, José Eduardo

    2016-01-01

    Annonaceous acetogenins are botanical compounds with good potential for use as insecticides. In the vector, Aedes aegypti (L.) (Diptera: Culicidae), squamocin (acetogenin) has been reported to be a larvicide and cytotoxic, but the modes of action of this molecule are still poorly understood. This study evaluated the changes in the cell morphology, and in the expression of genes, for autophagy (Atg1 and Atg8), for membrane ion transporter V-ATPase, and for water channel aquaporin-4 (Aqp4) in the midgut of A. aegypti larvae exposed to squamocin from Annona mucosa Jacq. (Annonaceae). Squamocin showed cytotoxic action with changes in the midgut epithelium and digestive cells of A. aegypti larvae, increase in the expression for autophagy gene Atg1 and Atg8, decrease in the expression of V-ATPase, decrease in the expression of Aqp4 gene in LC20 and inhibition of Apq4 genes in the midgut of this vector in LC50. These multiple modes of action for squamocin are described for the first time in insects, and they are important because different sites of action of squamocin from A. mucosa may reduce the possibility of resistance of A. aegypti to this molecule. PMID:27532504

  7. STUDIES ON AEDES AEGYPTI RESISTANCE TO SOME INSECTICIDES IN THE JAZAN DISTRICT, SAUDI ARABIA.

    Science.gov (United States)

    Alsheikh, Adel A; Mohammed, W S; Noureldin, E M; Daffalla, O M; Shrwani, Y A; Hobani, K J; Alsheikh, F A; Alzahrani, M H; Binsaeed, A A

    2016-04-01

    The present study provided information on the susceptibility status of the adult and larvae of Aedes aegypti mosquitoes in Jazan region of Saudi Arabia. Bioassay tests were performed on adults and larvae by using WHO recommended concentrations and test kits. Adults of Ae. aegypti mosquitoes were exposed to test papers impregnated with Lambda-cyhalothrin (0.05%), Cyfluthrin (0.15%), Deltamethrin (0.05%), Permethrin (0.75%), Fenitrothion (1%), Bendiocarb (0.1%) and DDT (4%) insecticides. Ae. aegypti mosquitoes were found to be susceptible only to Cyfluthrin; (mortality rate was 100%), whereas variable resistances were observed from the rest of the other insecticides tested (mortality rates ranged between 93.6 and 17%). Larvae were subjected to different concentrations of Diflubenzuron, Methoprene (IGRs) and Temephos (Organophosphate). Adult emergence inhibition (IE₅₀ & IE₉₅) values for the IGRs and the (LC₅₀ & LC₉₅) for Temephos were determined by log-probit regression analysis. Ae. aegypti larvae were resistant to Temephos (LC₅₀ 61.8-LC₉₅ 35600.1 mg/l) and showed high susceptibility to Methoprene than Diflubenzuron (IE₅₀ 0.49-IE₉₅ 10.9 mg/l) and (IE₅₀ 0.86 and IE₉₅ 93.8 mg/l), respectively. Larvae were more susceptible to Methoprene than Diflubenzuron by 1.8 folds. PMID:27363057

  8. Deltamethrin:Promising mosquito control agent against adult stage of Aedes aegypti L

    Institute of Scientific and Technical Information of China (English)

    Sarita Kumar; Anita Thomas; Pillai MKK

    2011-01-01

    Objective:To evaluate the effects of deltamethrin against field-collected adults of Aedes aegypti L. (Ae. aegypti). Methods: The adults were selected with 0.025%deltamethrin for 40 successive generations. The selected adults were tested with 4%DDT and the emerging larvae were tested with various insecticides to study the cross-resistance spectrum. The knockdown and irritability studies were carried out in adult mosquitoes to investigate their behavioural response to deltamethrin. Results:Forty generations of selection with deltamethrin resulted in only 3.8-fold resistance in the adults of Ae. aegypti. The adults of parent (PS) and selected strains (DAS) exhibited only 0.8-fold cross resistance to 4%DDT. The larvae emerging from the PS and DAS strains did not develop appreciable levels of resistance to various insecticides tested. The knockdown studies revealed KT50 of 14.4 min in PS adults with no signs of recovery even after 24 h. The DAS strains could develop only 1.2 to 1.3-fold knockdown resistance (KDR). The knockdown response of DDT was though 5-6 times slower than deltamethrin but the continued response in deltamethrin-selected adults caused only 1.2-fold KDR. The PS and DAS strains exhibited significant irritability response towards deltamethrin and DDT. The DAS strains showed 5-6 fold increased irritability to deltamethrin as compared to the PS strain. Conclusions:The above results suggest the prolonged effective use of deltamethrin against Ae. aegypti as an adulticide.

  9. Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Rosario; Ruiz-Guerrero; Mario; Alberto; Rodríguez-Pérez; Mariano; Norzagaray-Campos

    2015-01-01

    Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and Pseudosmodingium perniciosum(P. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue vector.Results: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(LC50 values ranged between 20 and 890 μg/mL). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of P. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(LC50 values were80, 50, and 20 μg/mL, respectively), thus making them potential candidates as biolarvicides.Efforts are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue vector.Conclusions: A. mexicana and P. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

  10. Agave sisalana extract induces cell death in Aedes aegypti hemocytes increasing nitric oxide production

    Institute of Scientific and Technical Information of China (English)

    Fabrine Felipe Hilario; Gabriel Joventino Nascimento; Joo Paulo Saraiva Morais; Everaldo Paulo de Medeiros; Manoel Francisco de Sousa; Fabiola da Cruz Nunes

    2016-01-01

    Objective: To investigate the effects of Agave sisalana (A. sisalana) extract on Aedes aegypti (Ae. aegypti) primary cell culture. Methods: Cells of Ae. aegypti were exposed to different concentrations of A. sisalana crude extract (0.18–6.00 mg/mL) for 24 h. Then, the cells were labeled with propidium iodide and subjected to fluorescence microscopy to verify cell viability. In addition, nitric oxide production was measured. Results: Results showed that cells exposed to 6 mg/mL of the crude extract presented a greater percentage of death when compared to control (73.8%± 9.6%vs. 34.6%± 9.6%). Furthermore, there was an increase in the nitric oxide production in cells exposed to 6 mg/mL of A. sisalana crude extract [(0.81 ± 0.08) mmol/L] compared to control group [(0.41 ± 0.18) mmol/L]. Conclusions: The results show that A. sisalana is cytotoxic to Ae. aegypti and may be used as raw material for new eco-friendly and inexpensive insecticides, since sisal in-dustry discards the liquid waste for the extraction of plant fiber.

  11. Genetics and morphology of Aedes aegypti (Diptera: Culicidae) in septic tanks in Puerto Rico.

    Science.gov (United States)

    Somers, Gerard; Brown, Julia E; Barrera, Roberto; Powell, Jeffrey R

    2011-11-01

    Dengue viruses, primarily transmitted by the mosquito Aedes aegypti (L.), affect an estimated 50-100 million people yearly. Traditional approaches to control mosquito population numbers, such as the use of pesticides, have had only limited success. Atypical mosquito behavior may be one reason why current vector control efforts have been less efficacious than expected. In Puerto Rico, for example, adult Ae. aegypti have been observed emerging from septic tanks. Interestingly, adults emerging from septic tanks are larger on average than adults collected from surface containers. To determine whether adults colonizing septic tanks constitute a separate Ae. aegypti population, we used 12 previously validated microsatellite loci to examine adult mosquitoes collected from both septic tanks and surface containers, but found no evidence to suggest genetic differentiation. Size differences between septic tank and surface mosquitoes were reduced when nutrient levels were held constant across experimental groups. Despite the absence of evidence suggesting a genetic difference between experimental groups in this study, Ae. aegypti emerging from septic tanks may still represent a more dangerous phenotype and should be given special consideration when developing vector control programs and designing public health interventions in the future.

  12. Complement-related proteins control the flavivirus infection of Aedes aegypti by inducing antimicrobial peptides.

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    Xiaoping Xiao

    2014-04-01

    Full Text Available The complement system functions during the early phase of infection and directly mediates pathogen elimination. The recent identification of complement-like factors in arthropods indicates that this system shares common ancestry in vertebrates and invertebrates as an immune defense mechanism. Thioester (TE-containing proteins (TEPs, which show high similarity to mammalian complement C3, are thought to play a key role in innate immunity in arthropods. Herein, we report that a viral recognition cascade composed of two complement-related proteins limits the flaviviral infection of Aedes aegypti. An A. aegypti macroglobulin complement-related factor (AaMCR, belonging to the insect TEP family, is a crucial effector in opposing the flaviviral infection of A. aegypti. However, AaMCR does not directly interact with DENV, and its antiviral effect requires an A. aegypti homologue of scavenger receptor-C (AaSR-C, which interacts with DENV and AaMCR simultaneously in vitro and in vivo. Furthermore, recognition of DENV by the AaSR-C/AaMCR axis regulates the expression of antimicrobial peptides (AMPs, which exerts potent anti-DENV activity. Our results both demonstrate the existence of a viral recognition pathway that controls the flaviviral infection by inducing AMPs and offer insights into a previously unappreciated antiviral function of the complement-like system in arthropods.

  13. Impact of small variations in temperature and humidity on the reproductive activity and survival of Aedes aegypti (Diptera, Culicidae); Impacto de pequenas variacoes de temperatura e umidade na atividade reprodutiva e sobrevivencia de Aedes aegypti (Diptera, Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ethiene Arruda Pedrosa de Almeida; Santos, Eloina Maria de Mendonca; Correia, Juliana Cavalcanti; Albuquerque, Cleide Maria Ribeiro de, E-mail: cleide.ufpe@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Ciencias Biologicas. Dept. de Zoologia

    2010-07-01

    In short space of time increase in temperature and rainfall can affect vector populations and, consequently, the diseases for them transmitted. The present study analyzed the effect of small temperature and humidity variations on the fecundity, fertility and survival of Aedes aegypti. These parameters were analyzed using individual females at temperatures ranging from 23 to 27 deg C (mean 25 deg C); 28 to 32 deg C (mean 30 deg C) and 33 to 37 deg C (mean 35 deg C) associated to 60 +- 8% and 80 +- 6% relative humidity. Females responded to an increase in temperature by reducing egg production, oviposition time and changing oviposition patterns. At 25 deg C and 80% relative humidity, females survived two-fold more and produced 40% more eggs when compared to those kept at 35 deg C and 80% relative humidity. However, in 45% of females kept at 35 deg C and 60% relative humidity oviposition was inhibited and only 15% females laid more than 100 eggs, suggesting that the intensity of the temperature effect was influenced by humidity. Gradual reductions in egg fertility at 60% relative humidity were observed with the increase in temperature, although such effect was not found in the 80% relative humidity at 25 deg C and 30 deg C. These results suggest that the reduction in population densities recorded in tropical areas during seasons when temperatures reach over 35 deg C is likely to be strongly influenced by temperature and humidity, with a negative effect on several aspects of mosquito biology. (author)

  14. Immunotoxicity activity of sesquiterpenoids from black galingale (Kaempferia parviflora Wall. Ex. Baker) against Aedes aegypti L.

    Science.gov (United States)

    Moon, Hyung-In; Cho, Sang-Buem; Lee, Jun-Hyeong; Paik, Hyun-Dong; Kim, Soo-Ki

    2011-06-01

    The roots of black galingale (Kaempferia parviflora) were chloroform-extracted and the isolated two sesquiterpene and immunotoxicity effects were studied. The structures and stereochemistry of these compounds were established on the basis of analysis of spectra including UV, MS, (1)H-NMR, and (13)C-NMR as follows: 1 (4α-acetoxycadina-2,9-diene-1,8-dione), 2 (1α,3α,4β-trihydroxy-9-cadinen-8-one). Compound 2 had a significant toxic effect against early fourth-stage larvae of Aedes aegypti L. with an LC(50) value of 0.7 μM and an LC(90) value of 3.8 μM. The results could be useful in search for newer, safer, and more effective natural immunotoxicity agents against A. aegypti. PMID:20925462

  15. Effect of Wolbachia on insecticide susceptibility in lines of Aedes aegypti.

    Science.gov (United States)

    Endersby, N M; Hoffmann, A A

    2013-06-01

    Two stable infections of Wolbachia pipientis, wMelPop and wMel, now established in Aedes aegypti, are being used in a biocontrol program to suppress the transmission of dengue. Any effects of Wolbachia infection on insecticide resistance of mosquitoes may undermine the success of this program. Bioassays of Ae. aegypti were conducted to test for differences in response to insecticides between Wolbachia infected (wMelPop, wMel) and uninfected lines. Insecticides screened were bifenthrin, the pyrethroid commonly used for adult knockdown, as well as larvicides: Bacillus thuringiensis var. israelensis, the organophosphate, temephos and the insect growth regulator, s-methoprene. While differences in response between lines were detected for some insecticides, no obvious or consistent effects related to presence of Wolbachia infection were observed. Spreading Wolbachia infections are, therefore, unlikely to affect the efficacy of traditional chemical control of mosquito outbreaks. PMID:23149015

  16. Resistance Status to the Insecticides Temephos, Deltamethrin, and Diflubenzuron in Brazilian Aedes aegypti Populations

    Science.gov (United States)

    Viana-Medeiros, Priscila Fernandes; Araújo, Simone Costa; Martins, Ademir J.; Lima, José Bento Pereira

    2016-01-01

    Insecticides are still largely applied in public health to control disease vectors. In Brazil, organophosphates (OP) and pyrethroids (PY) are used against Aedes aegypti for years. Since 2009 Insect Growth Regulators (IGR) are also employed in the control of larvae. We quantified resistance to temephos (OP), deltamethrin (PY), and diflubenzuron (IGR) of A. aegypti samples from 12 municipalities distributed throughout the country, collected between 2010 and 2012. High levels of resistance to neurotoxic insecticides were detected in almost all populations: RR95 to temephos varied between 4.0 and 27.1; the lowest RR95 to deltamethrin was 13.1, and values higher than 70.0 were found. In contrast, all samples were susceptible to diflubenzuron (RR95 insecticides during dengue epidemic seasons in the evaluated municipalities. PMID:27419140

  17. Repellence of essential oils of aromatic plants growing in Argentina against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Gleiser, Raquel M; Bonino, Maria A; Zygadlo, Julio A

    2011-01-01

    Mosquitoes are vectors of pathogens to humans and domestic animals and may also have economical impacts. One approach to prevent mosquito-borne diseases is bite deterrence through the application of repellents. Currently, there is an interest to search for alternative bioactive products to the synthetic active ingredients most widely used in insect repellents. Repellence against Aedes aegypti of essential oils extracted from Acantholippia salsoloides, Aloysia catamarcensis, Aloysia polystachya, Lippia integrifolia, Lippia junelliana (Verbenaceae), Baccharis salicifolia, Euphatorium buniifolium, and Tagetes filifolia (Asteraceae) were assessed. Tests were conducted by alternatively exposing untreated and treated forehand to the mosquitoes and counting probing attempts. All essential oils tested were significantly repellent against A. aegypti when compared to untreated controls; L. junelliana was the most repellent and T. filifolia was the least based on the response of the mosquitoes to different concentrations of the essential oils (EO). Repellence may be attributed to the respective main components of each EO. PMID:20838809

  18. HPTLC analysis of Scoparia dulcis Linn (Scrophulariaceae) and its larvicidal potential against dengue vector Aedes aegypti.

    Science.gov (United States)

    Wankhar, Wankupar; Srinivasan, Sakthivel; Rathinasamy, Sheeladevi

    2015-01-01

    This study evaluates the larvicidal activity of Scoparia dulcis aqueous extract against dengue vector and determines its major chemical components. The extract was tested at various concentrations ranging from 0.1 to 2 mg/mL against Aedes aegypti larvae. The extracts displayed significant larvicidal efficacy against Ae. aegypt species after 24 h exposure revealing LC50 of 3.3835 (mg/mL) and LC90 of 5.7578 (mg/mL). Finger printing profile carried out by CAMAG automatic TLC sample applicator programmed through WIN CATS software revealed peaks with different Rf values for three different volumes injected: 16, 15 and 18 peaks were spotted for 3, 6 and 9 μL, respectively. Ascending order of Rf values was also ascertained for each peak recorded. This study clearly signifies that S. dulcis extract contains numerous compounds that are known to have larvicidal properties which clearly substantiates its efficacy on Ae. aegypti larvae. PMID:25573588

  19. Effects of larval crowding on development time, survival and weight at metamorphosis in Aedes aegypti (Diptera: Culicidae Efectos del hacinamiento larval en el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis de Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Arnaldo Maciá

    2009-06-01

    Full Text Available The effects of larval crowding on survival, weight at metamorphosis and development time were assessed in the dengue mosquito, Aedes aegypti L., under a controlled environment. Larval cohorts were bred at 7 different densities (4, 8, 16, 32, 64, 128 and 256 larvae / 175 ml pot, while keeping constant water volume and food amount and quality, under controlled temperature and photoperiod. Natural detritus, mainly leaves, obtained from containers naturally colonized by A. aegypti, were used as a source of nutrients for larvae. Development time, mortality, mass at metamorphosis, and total biomass were recorded for each density. Development time ranged from 4 to 23 days in males, and from 5 to 24 in females, whereby larvae took longer to develop at 64 (females and 128 (males larvae per recipient. At high densities there was a male-biased sex proportion. At densities equal to or higher than 0.4 larvae/ml (0.32 larvae/cm² there was an increase of mortality. An inverse relationship between larval density and pupal weight was detected. Biomass per individual reached asymptotic values of about 1 mg/individual at a density of 128 individuals/pot (0.64 larvae/cm². This experiment shows that this southern strain of A. aegypti is sensitive to crowding in small containers.Los efectos del hacinamiento larval sobre el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis fueron estudiados en el mosquito del dengue, Aedes aegypti L., en el laboratorio. Se criaron cohortes de larvas en 7 densidades (4, 8, 16, 32, 64, 128 y 256 larvas/ recipiente de 175 ml mientras se mantuvo constante el volumen de agua y la calidad y cantidad de alimento, bajo fotoperíodo y temperatura controlados. Se usaron detritos naturales, principalmente hojas, obtenidos de contenedores colonizados naturalmente por A. aegypti como fuente de nutrientes para las larvas. En cada densidad se registraron el tiempo de desarrollo, la mortalidad, el peso en la metamorfosis y la

  20. Dual African origins of global Aedes aegypti s.l. populations revealed by mitochondrial DNA.

    Directory of Open Access Journals (Sweden)

    Michelle Moore

    Full Text Available BACKGROUND: Aedes aegypti is the primary global vector to humans of yellow fever and dengue flaviviruses. Over the past 50 years, many population genetic studies have documented large genetic differences among global populations of this species. These studies initially used morphological polymorphisms, followed later by allozymes, and most recently various molecular genetic markers including microsatellites and mitochondrial markers. In particular, since 2000, fourteen publications and four unpublished datasets have used sequence data from the NADH dehydrogenase subunit 4 mitochondrial gene to compare Ae. aegypti collections and collectively 95 unique mtDNA haplotypes have been found. Phylogenetic analyses in these many studies consistently resolved two clades but no comprehensive study of mtDNA haplotypes have been made in Africa, the continent in which the species originated. METHODS AND FINDINGS: ND4 haplotypes were sequenced in 426 Ae. aegypti s.l. from Senegal, West Africa and Kenya, East Africa. In Senegal 15 and in Kenya 7 new haplotypes were discovered. When added to the 95 published haplotypes and including 6 African Aedes species as outgroups, phylogenetic analyses showed that all but one Senegal haplotype occurred in a basal clade while most East African haplotypes occurred in a second clade arising from the basal clade. Globally distributed haplotypes occurred in both clades demonstrating that populations outside Africa consist of mixtures of mosquitoes from both clades. CONCLUSIONS: Populations of Ae. aegypti outside Africa consist of mosquitoes arising from one of two ancestral clades. One clade is basal and primarily associated with West Africa while the second arises from the first and contains primarily mosquitoes from East Africa.

  1. SEASONAL ABUNDANCE OF ADULT AND IMMATURE AEDES AEGYPTI (L.) IN JAKARTA

    OpenAIRE

    M. J. Nelson; Salim Usman; C. P. Pant; Self, L. S.

    2012-01-01

    Dari bulan Mei 1973 sampai bulan Juni 1974 telah dilakukan pengamatan nyamuk Aedes aegypti stadium dewasa dan larva di keempat daerah kota yang berpenduduk padat di Jakarta Raya. Pengamatan dikerjakan 2 kali dalam satu bulan Daya tarik nyamuk terhadap manusia rata-rata 1.2 induk betina dan 1.6 untuk nyamuk jantan tiap orang tiap jam. Dalam 100 rumah diketemukan rata-rata 180 buah bejana berisi air, dimana 58 buah positif; Container index (persentasi bejana yang tositif) 32 persen House index ...

  2. Repellent Action Of Neem (Azadiracta India) Seed Oil Against Aedes Aegypti Mosquitoes

    OpenAIRE

    Hati A K; Bhowmik Keya; Banerjee A; Mukherjee H; Poddar G; Basu D; Dhara K P

    1995-01-01

    Neem (Azadiracta India) seed oil in appropriate amount when smeared on the surface of the hand showed excellent repellent action against Aedes aegypti mosquitoes. When 1 ml of oil was spread on the hand, with an approximate area of 160 sq cm the percentage of alighting and blood fed mosquitoes in the experimental cages varied from 14 to 78 and 4 to 46 respectively. This percentage decreased to 6 to 18 and 0 to 16 respectively when the amount of oil applied was 1.5 ml. Only 0-4% of the ...

  3. Rotenoids from Tephrosia toxicaria with larvicidal activity against Aedes aegypti, the main vector of dengue fever

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    Jackson Nunes e Vasconcelos

    2012-01-01

    Full Text Available In the search for new larvicides from plants, we have investigated the potential activity of the rotenoids deguelin (1, 12a-hydroxy-α-toxicarol (2 and tephrosin (3, isolated from the bioactive ethanol extract of roots of Tephrosia toxicaria Pers., against Aedes aegypti, the main vector of dengue. The absolute configuration of these compounds was determined by circular dichroism (CD spectra. The LC50 values of the compounds evaluated justify the potential of T. toxicaria as a new natural larvicide.

  4. Promising Aedes aegypti repellent chemotypes identified through integrated QSAR, virtual screening, synthesis, and bioassay.

    Science.gov (United States)

    Oliferenko, Polina V; Oliferenko, Alexander A; Poda, Gennadiy I; Osolodkin, Dmitry I; Pillai, Girinath G; Bernier, Ulrich R; Tsikolia, Maia; Agramonte, Natasha M; Clark, Gary G; Linthicum, Kenneth J; Katritzky, Alan R

    2013-01-01

    Molecular field topology analysis, scaffold hopping, and molecular docking were used as complementary computational tools for the design of repellents for Aedes aegypti, the insect vector for yellow fever, chikungunya, and dengue fever. A large number of analogues were evaluated by virtual screening with Glide molecular docking software. This produced several dozen hits that were either synthesized or procured from commercial sources. Analysis of these compounds by a repellent bioassay resulted in a few highly active chemicals (in terms of minimum effective dosage) as viable candidates for further hit-to-lead and lead optimization effort.

  5. Efeito residual de temephós em larvas de Aedes aegypti

    OpenAIRE

    Maria de Lourdes G Macoris; Maria Teresa M Andrighetti; Luiz Takaku

    1995-01-01

    Uma das estratégias de controle do Aedes aegypti é o uso do larvicida temephós, cujo efeito residual prolongado permite a programação de tratamentos focais. O objetivo deste estudo é verificar a duração do efeito residual do temephós simulando-se uma situação de campo. Recipientes plásticos com capacidade de um e cinco litros, foram tratados com temephós e seu efeito residual testado a cada trinta dias. Foram observadas diferentes durações do efeito residual, o qual foi maior nos recipientes ...

  6. Optimization of the Aedes aegypti Control Strategies for Integrated Vector Management

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    Marat Rafikov

    2015-01-01

    Full Text Available We formulate an infinite-time quadratic functional minimization problem of Aedes aegypti mosquito population. Three techniques of mosquito population management, chemical insecticide control, sterile insect technique control, and environmental carrying capacity reduction, are combined in order to obtain the most sustainable strategy to reduce mosquito population and consequently dengue disease. The solution of the optimization control problem is based on the ideas of the Dynamic Programming and Lyapunov Stability using State-Dependent Riccati Equation (SDRE control method. Different scenarios are analyzed combining three mentioned population management efforts in order to assess the most sustainable policy to reduce the mosquito population.

  7. Comportamento de formas imaturas de Aedes aegypti, no litoral do Estado de São Paulo

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    Carmen Moreno Glasser

    2011-06-01

    Full Text Available INTRODUÇÃO: Em região de alta incidência de dengue, no litoral do Estado de São Paulo, selecionaram-se 9 áreas, com objetivo de avaliar o comportamento de formas imaturas de Aedes aegypti. MÉTODOS: As 9 áreas foram agrupadas em 4 estratos, diferenciados pelo uso e ocupação do solo. Foram coletadas larvas e pupas numa amostra de cerca de 500 imóveis em cada área. RESULTADOS: Apesar do pneu e lona apresentarem as maiores taxas de positividade para Aedes aegypti, o ralo, juntamente com outros recipientes fixos nas edificações foram altamente predominantes entre os recipientes positivos (32 a 76% dos recipientes positivos. As áreas coletivas de prédios e os imóveis não residenciais de grande porte apresentaram as maiores taxas de positividade para Aedes aegypti enquanto os apartamentos, as menores. Os níveis de infestação foram maiores na área residencial com predominância de prédios de apartamentos, onde 76% dos criadouros detectados foram recipientes fixos nas edificações. CONCLUSÕES: Esses conhecimentos são importantes subsídios para a estratégia de controle, pois reforçam a necessidade de atenção especial para determinados tipos de imóveis, bem como da adequação da norma técnica de ralo de água pluvial e da melhoria de manutenção das edificações. Além disso, são necessárias observações sistemáticas que permitam acompanhar a dinâmica de ocupação de diferentes imóveis e recipientes por Aedes aegypti e a incorporação desses conhecimentos nas ações de controle do vetor na região.

  8. The combination of the entomopathogenic fungus Metarhizium anisopliae with the insecticide Imidacloprid increases virulence against the dengue vector Aedes aegypti (Diptera: Culicidae

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    Samuels Richard I

    2011-01-01

    Full Text Available Abstract Background Dengue fever transmitted by the mosquito Aedes aegypti, is one of the most rapidly spreading insect borne diseases, stimulating the search for alternatives to current control measures. The dengue vector A. aegypti has received less attention than anophelene species, although more than 2.5 billion people are at risk of infection worldwide. Entomopathogenic fungi are emerging as potential candidates for the control of mosquitoes. Here we continue our studies on the pathogenicity of the entomopathogenic fungus Metarhizium anisopliae against adult A. aegypti females. With the aim of further reducing mean survival times of A. aegypti exposed to fungus impregnated surfaces, a sub-lethal concentration of the neonicotinoid insecticide Imidacloprid (IMI was added to fungal suspensions. Results A sub-lethal concentration of IMI that did not significantly alter the daily survival rates or mean survival percentages of mosquitoes was identified to be 0.1 ppm. This sub-lethal concentration was combined with M. anisopliae conidia (1 × 109 conidia mL-1. Both the combined treatment and the conidia alone were able to reduce the survival of A. aegypti compared with untreated or IMI treated mosquitoes. Importantly, mosquito survival following exposure to the combined treatment for 6 and 12 hrs was significantly reduced when compared with mosquitoes exposed to conidia alone. Conclusions This is the first time that a combination of an insecticide and an entomopathogenic fungus has been tested against A. aegypti. Firstly, the study showed the potential of IMI as an alternative to the currently employed pyrethroid adulticides. Secondly, as an alternative to applications of high concentrations of chemical insecticides, we suggest that adult A. aegypti could be controlled by surface application of entomopathogenic fungi and that the efficiency of these fungi could be increased by combining the fungi with ultra-low concentrations of insecticides

  9. Seasonal Differences in Density But Similar Competitive Impact of Aedes albopictus (Skuse) on Aedes aegypti (L.) in Rio de Janeiro, Brazil

    Science.gov (United States)

    Camara, Daniel Cardoso Portela; Codeço, Claudia Torres; Juliano, Steven A.; Lounibos, L. Philip; Riback, Thais Irene Souza; Pereira, Glaucio Rocha; Honorio, Nildimar Alves

    2016-01-01

    Previous studies have shown that the negative effects of density of Ae. albopictus on Ae. aegypti exceed those of Ae. aegypti on Ae. albopictus for population growth, adult size, survivorship, and developmental rate. This competitive superiority has been invoked to explain the displacement of Ae. aegypti by Ae. albopictus in the southeastern USA. In Brazil, these species coexist in many vegetated suburban and rural areas. We investigated a related, but less-well-studied question: do effects of Ae. albopictus on Ae. aegypti larval development and survival occur under field conditions at realistic densities across multiple seasons in Brazil? We conducted additive competition experiments in a vegetated area of Rio de Janeiro where these species coexist. We tested the hypothesis that Ae. aegypti (the focal species, at a fixed density) suffers negative effects on development and survivorship across a gradient of increasing densities of Ae. albopictus (the associate species) in three seasons. The results showed statistically significant effects of both season and larval density on Ae. aegypti survivorship, and significant effects of season on development rate, with no significant season-density interactions. Densities of Aedes larvae in these habitats differed among seasons by a factor of up to 7x. Overall, Spring was the most favorable season for Ae. aegypti survivorship and development. Results showed that under natural conditions the negative competitive effects of Ae. albopictus on Ae. aegypti were expressed primarily as lower survivorship. Coexistence between Ae. aegypti and Ae. albopictus in vegetated areas is likely affected by seasonal environmental differences, such as detrital resource levels or egg desiccation, which can influence competition between these species. Interactions between these Aedes are important in Brazil, where both species are well established and widely distributed and vector dengue, Zika and chikungunya viruses. PMID:27322537

  10. Seasonal Differences in Density But Similar Competitive Impact of Aedes albopictus (Skuse on Aedes aegypti (L. in Rio de Janeiro, Brazil.

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    Daniel Cardoso Portela Camara

    Full Text Available Previous studies have shown that the negative effects of density of Ae. albopictus on Ae. aegypti exceed those of Ae. aegypti on Ae. albopictus for population growth, adult size, survivorship, and developmental rate. This competitive superiority has been invoked to explain the displacement of Ae. aegypti by Ae. albopictus in the southeastern USA. In Brazil, these species coexist in many vegetated suburban and rural areas. We investigated a related, but less-well-studied question: do effects of Ae. albopictus on Ae. aegypti larval development and survival occur under field conditions at realistic densities across multiple seasons in Brazil? We conducted additive competition experiments in a vegetated area of Rio de Janeiro where these species coexist. We tested the hypothesis that Ae. aegypti (the focal species, at a fixed density suffers negative effects on development and survivorship across a gradient of increasing densities of Ae. albopictus (the associate species in three seasons. The results showed statistically significant effects of both season and larval density on Ae. aegypti survivorship, and significant effects of season on development rate, with no significant season-density interactions. Densities of Aedes larvae in these habitats differed among seasons by a factor of up to 7x. Overall, Spring was the most favorable season for Ae. aegypti survivorship and development. Results showed that under natural conditions the negative competitive effects of Ae. albopictus on Ae. aegypti were expressed primarily as lower survivorship. Coexistence between Ae. aegypti and Ae. albopictus in vegetated areas is likely affected by seasonal environmental differences, such as detrital resource levels or egg desiccation, which can influence competition between these species. Interactions between these Aedes are important in Brazil, where both species are well established and widely distributed and vector dengue, Zika and chikungunya viruses.

  11. Evaluación del efecto residual del Temephos en larvas de Aedes aegypti en Lima, Perú

    OpenAIRE

    Miriam Palomino S; Lely Solari; Walter León C; Rosario Vega H; Máximo Vergaray C; Luis Cubillas; Rosa Mosqueda C; Norma García A

    2006-01-01

    El temephos ha sido usado como la única estrategia de control para Aedes aegypti en Lima durante los últimos años. Objetivo: Evaluar la eficacia residual de temephos para el control de Ae. aegypti en condiciones de campo y laboratorio en Lima, Perú. Materiales y métodos: Se eligieron ocho tanques bajos de concreto (TBC) depósitos predominantemente infestados con Ae. aegypti en el distrito de San Juan de Lurigancho, situado al norte del área suburbana de Lima. Se cuantificó el número de larvas...

  12. Isolation and selection of local isolates of chitinolitic bacteria that potent to biocontrol of larva stadia of Aedes aegypti L.

    Directory of Open Access Journals (Sweden)

    SRI PUJIYANTO

    2008-01-01

    Full Text Available The dengue fever was the most dangerously epidemic in Indonesia, so it is important to prevent the population of Aedes aegypti L. The larva stages of Ae. aegypti had an exosceleton from chitin, so if its exosceleton had been degraded the larva would be died. Many bacteria had chitin degradation activities, and the bacteria had potential as a biocontrol for Ae. aegypti larva stages. This research was got many of the local chitinolitic bacteria that had been potential as a biocontrol for Ae. aegypti larva stages. The chitinolitic bacteria were isolated with selective agar medium. The sources of isolates were collected from Central Java and West Java water resources. Selected isolates was done to get the higher chitinolitic activity in mineral water medium. The isolate LMB1-5 was potential as a bioinsecticide for Ae. aegypti larva stages. This isolate decreased 86.7% of the larva population in 7 days.

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

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    M. Deepa

    2014-12-01

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

  14. The Efficacy of Some Commercially Available Insect Repellents for Aedes aegypti (Diptera: Culicidae) and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Rodriguez, Stacy D; Drake, Lisa L; Price, David P; Hammond, John I; Hansen, Immo A

    2015-01-01

    Reducing the number of host-vector interactions is an effective way to reduce the spread of vector-borne diseases. Repellents are widely used to protect humans from a variety of protozoans, viruses, and nematodes. DEET (N,N-Diethyl-meta-toluamide), a safe and effective repellent, was developed during World War II. Fear of possible side effects of DEET has created a large market for "natural" DEET-free repellents with a variety of active ingredients. We present a comparative study on the efficacy of eight commercially available products, two fragrances, and a vitamin B patch. The products were tested using a human hand as attractant in a Y-tube olfactometer setup with Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse), both major human disease vectors. We found that Ae. albopictus were generally less attracted to the test subject's hand compared with Ae, aegypti. Repellents with DEET as active ingredient had a prominent repellency effect over longer times and on both species. Repellents containing p-menthane-3,8-diol produced comparable results but for shorter time periods. Some of the DEET-free products containing citronella or geraniol did not have any significant repellency effect. Interestingly, the perfume we tested had a modest repellency effect early after application, and the vitamin B patch had no effect on either species. This study shows that the different active ingredients in commercially available mosquito repellent products are not equivalent in terms of duration and strength of repellency. Our results suggest that products containing DEET or p-menthane-3,8-diol have long-lasting repellent effects and therefore provide good protection from mosquito-borne diseases. PMID:26443777

  15. Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents.

    Science.gov (United States)

    Qualls, Whitney A; Day, Jonathan F; Xue, Rui-de; Bowers, Doria F

    2012-06-01

    Changes in the time to first bite (TFB) and the bloodfeeding behavior of adult female Aedes aegypti (L.) mosquitoes following dissemination of Sindbis virus (SINV) were observed after exposure to repellents with the active ingredients (AI) DEET, picaridin, 2-undecanone (2-U), and oil of lemon eucalyptus. Dissemination of SINV significantly decreased (PTFB of DEET (15%) and picaridin (15%) by 46% and 37%, respectively. Significant (PTFB and time to complete the four bloodfeeding stages will lessen the prey-status, and enhance both the chances of mosquito survival and arbovirus transmission. PMID:22289669

  16. Determination of juvenile hormone titers by means of LC-MS/MS/MS and a juvenile hormone-responsive Gal4/UAS system in Aedes aegypti mosquitoes.

    Science.gov (United States)

    Zhao, Bo; Hou, Yuan; Wang, Jianjun; Kokoza, Vladimir A; Saha, Tusar T; Wang, Xue-Li; Lin, Ling; Zou, Zhen; Raikhel, Alexander S

    2016-10-01

    In anautogenous mosquitoes, juvenile hormone III (JH) plays an essential role in female post-eclosion (PE) development, preparing them for subsequent blood feeding and egg growth. We re-examined the JH titer during the reproductive cycle of female Aedes aegypti mosquitoes. Using liquid chromatography coupled with triple tandem mass spectrometry (LC-MS/MS/MS), we have shown that it reaches its peak at 48-54 h PE in the female hemolymph and at 72 h PE in whole body extracts. This method represents an effective assay for determination of JH titers. The 2.1-kb 5' promoter region of the Early Trypsin (ET) gene, which is specifically expressed in the female midgut under the control of JH during the PE phase, was utilized to genetically engineer the Ae. aegypti mosquito line with the ET-Gal4 activator. We then established the ET-GAL4>UAS-enhanced green fluorescent protein (EGFP) system in Ae. aegypti. In ET-Gal4>UAS-EGFP female mosquitoes, the intensity of the midgut-specific EGFP signal was observed to correspond to the ET gene transcript level and follow the JH titer during the PE phase. The EGFP signal and the EGFP transcript level were significantly diminished in midguts of transgenic female mosquitoes after RNA interference depletion of the JH receptor Methoprene-tolerant (Met), providing evidence of the control of ET gene expression by Met. Topical JH application caused premature enhancement of the EGFP signal and the EGFP transcript level in midguts of newly eclosed ET-Gal4>UAS-EGFP female mosquitoes, in which endogenous JH titer is still low. Hence, this novel ET-Gal4>UAS system permits JH-dependent gene overexpression in the midgut of Ae. aegypti female mosquitoes prior to a blood meal. PMID:27530057

  17. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae population in California [version 3; referees: 2 approved

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    Anthony J. Cornel

    2016-08-01

    Full Text Available The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B, when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV trials using a new formulation of deltamethrin (DeltaGard® demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath after a single truck mounted aerial ULV application in residential areas.

  18. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae population in California [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Anthony J. Cornel

    2016-03-01

    Full Text Available The invasion and subsequent establishment in California of Aedes aegypti in 2013 has created new challenges for local mosquito abatement and vector control districts. Studies were undertaken to identify effective and economical strategies to monitor the abundance and spread of this mosquito species as well as for its control. Overall, BG Sentinel (BGS traps were found to be the most sensitive trap type to measure abundance and spread into new locations. Autocidal-Gravid-Ovitraps (AGO-B, when placed at a site for a week, performed equally to BGS in detecting the presence of female Ae. aegypti. Considering operational cost and our findings, we recommend use of BGS traps for surveillance in response to service requests especially in locations outside the known infestation area. We recommend AGO-Bs be placed at fixed sites, cleared and processed once a week to monitor mosquito abundance within a known infestation area. Long-term high density placements of AGO-Bs were found to show promise as an environmentally friendly trap-kill control strategy. California Ae. aegypti were found to be homozygous for the V1016I mutation in the voltage gated sodium channel gene, which is implicated to be involved in insecticide resistance. This strain originating from Clovis, California was resistant to some pyrethroids but not to deltamethrin in bottle bio-assays. Sentinel cage ultra-low-volume (ULV trials using a new formulation of deltamethrin (DeltaGard® demonstrated that it provided some control (average of 56% death in sentinel cages in a 91.4 m spray swath after a single truck mounted aerial ULV application in residential areas.

  19. An integrated linkage, chromosome, and genome map for the yellow fever mosquito Aedes aegypti.

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    Vladimir A Timoshevskiy

    Full Text Available BACKGROUND: Aedes aegypti, the yellow fever mosquito, is an efficient vector of arboviruses and a convenient model system for laboratory research. Extensive linkage mapping of morphological and molecular markers localized a number of quantitative trait loci (QTLs related to the mosquito's ability to transmit various pathogens. However, linking the QTLs to Ae. aegypti chromosomes and genomic sequences has been challenging because of the poor quality of polytene chromosomes and the highly fragmented genome assembly for this species. METHODOLOGY/PRINCIPAL FINDINGS: Based on the approach developed in our previous study, we constructed idiograms for mitotic chromosomes of Ae. aegypti based on their banding patterns at early metaphase. These idiograms represent the first cytogenetic map developed for mitotic chromosomes of Ae. aegypti. One hundred bacterial artificial chromosome clones carrying major genetic markers were hybridized to the chromosomes using fluorescent in situ hybridization. As a result, QTLs related to the transmission of the filarioid nematode Brugia malayi, the avian malaria parasite Plasmodium gallinaceum, and the dengue virus, as well as sex determination locus and 183 Mbp of genomic sequences were anchored to the exact positions on Ae. aegypti chromosomes. A linear regression analysis demonstrated a good correlation between positions of the markers on the physical and linkage maps. As a result of the recombination rate variation along the chromosomes, 12 QTLs on the linkage map were combined into five major clusters of QTLs on the chromosome map. CONCLUSION: This study developed an integrated linkage, chromosome, and genome map-iMap-for the yellow fever mosquito. Our discovery of the localization of multiple QTLs in a few major chromosome clusters suggests a possibility that the transmission of various pathogens is controlled by the same genomic loci. Thus, the iMap will facilitate the identification of genomic determinants of

  20. Spatial Patterns of High Aedes aegypti Oviposition Activity in Northwestern Argentina

    Science.gov (United States)

    Estallo, Elizabet Lilia; Más, Guillermo; Vergara-Cid, Carolina; Lanfri, Mario Alberto; Ludueña-Almeida, Francisco; Scavuzzo, Carlos Marcelo; Introini, María Virginia; Zaidenberg, Mario; Almirón, Walter Ricardo

    2013-01-01

    Background In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. Methodology Oviposition activity was detected in Orán City (Salta province) using ovitraps, weekly replaced (October 2005–2007). Spatial autocorrelation was measured with Moran’s Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR) sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. Principal Findings Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC = 0.77), obtaining 99% of sensitivity and 75.29% of specificity. Conclusions Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist National Health

  1. Evaluation of herbal essential oil as repellents against Aedes aegypti (L.) and Anopheles dirus Peyton & Harrion

    Institute of Scientific and Technical Information of China (English)

    Duangkamon Sritabutra; Mayura Soonwera; Sirirat Waltanachanobon; Supaporn Poungjai

    2011-01-01

    Objective: To investigate the repellent activity of herbal essential oils from garlic (Allium sativum), clove (Syzygium aromaticum), lemon grass (Cybopogon citratus), citronella grass (Cymbopogon nardus), peppermint (Mentha piperita), eucalyptus (Eucalyptus globulus), orange (Citrus sinensis) and sweet basil (Ocimum basilicum) and their combinations against Aedes aegypti (Ae. aegypti) (L.) and Anopheles dirus (An. dirus) Peyton & Harrion under laboratory conditions.Methods:In laboratory condition, 0.1 mL of each essential oil was applied to 3-10 cm of exposed area on a volunteer’s forearm. The test was carried out every 30 min until fewer than two mosquitoes bit or land during the 3 min study period and then the repellency test was stopped.Results:Essential oil from lemon grass exhibited protection against biting from two mosquito species, for Ae. aegypti [(98.66±11.56) min protection time and 0.97% biting rate] and for An. dirus [(98.00±15.28) min protection time and 0.80% biting rate]. The combinations from eucalyptus oil and sweet basil oil were effective as repellents and feeding deterrents against Ae. aegypti [(98.87±10.28) min protection time and 0.90% biting rate] and An. dirus [(210±10.70) min protection time and 0.93% biting rate]. All herbal repellents exhibited the period of protection time against Ae. aegypti which was lower than 120 min. Conlussions: It can be concluded that oils of lemon grass and combination from eucalyptus-sweet basil are the most effective in repellent activity.

  2. The wMel Strain of Wolbachia Reduces Transmission of Chikungunya Virus in Aedes aegypti.

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    Matthew T Aliota

    2016-04-01

    Full Text Available New approaches to preventing chikungunya virus (CHIKV are needed because current methods are limited to controlling mosquito populations, and they have not prevented the invasion of this virus into new locales, nor have they been sufficient to control the virus upon arrival. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against CHIKV. Although this approach holds much promise for limiting virus transmission, at present our understanding of the ability of CHIKV to infect, disseminate, and be transmitted by wMel-infected Ae. aegypti currently being used at Wolbachia release sites is limited.Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for CHIKV, even with extremely high viral titers in the bloodmeal. In addition, we examined the dynamics of CHIKV infection over the course of four to seven days post feeding. Wolbachia-infected mosquitoes remained non-infective over the duration of seven days, i.e., no infectious virus was detected in the saliva when exposed to bloodmeals of moderate viremia, but CHIKV-exposed, wild type mosquitoes did have viral loads in the saliva consistent with what has been reported elsewhere. Finally, the presence of wMel infection had no impact on the lifespan of mosquitoes as compared to wild type mosquitoes following CHIKV infection.These results could have an impact on vector control strategies in areas where Ae. aegypti are transmitting both DENV and CHIKV; i.e., they argue for further exploration, both in the laboratory and the field, on the feasibility of expanding this technology beyond DENV.

  3. Aedes aegypti Global Suitability Maps Using a Water Container Energy Balance Model for Dengue Risk Applications

    Science.gov (United States)

    Steinhoff, D.

    2015-12-01

    Dengue infections are estimated to total nearly 400 million per year worldwide, with both the geographic range and the magnitude of infections having increased in the past 50 years. The primary dengue vector mosquito Aedes aegypti is closely associated with humans. It lives exclusively in urban and semi-urban areas, preferentially bites humans, and spends its developmental stages in artificial water containers. Climate regulates the development of Ae. aegypti immature mosquitoes in artificial containers. Potential containers for Ae. aegypti immature development include, but are not limited to, small sundry items (e.g., bottles, cans, plastic containers), buckets, tires, barrels, tanks, and cisterns. Successful development of immature mosquitoes from eggs to larvae, pupae, and eventually adults is largely dependent on the availability of water and the thermal properties of the water in the containers. Recent work has shown that physics-based approaches toward modeling container water properties are promising for resolving the complexities of container water dynamics and the effects on immature mosquito development. An energy balance container model developed by the author, termed the Water Height And Temperature in Container Habitats Energy Model (WHATCH'EM), solves for water temperature and height for user-specified containers with readily available weather data. Here we use WHATCH'EM with NASA Earth Science products used as input to construct global suitability maps based on established water temperature ranges for immature Ae. aegypti mosquitoes. A proxy for dengue risk is provided from habitat suitability, but also population estimates, as Ae. aegypti is closely associated with human activity. NASA gridded Global Population of the World data is used to mask out rural areas with low dengue risk. Suitability maps are illustrated for a variety of containers (size, material, color) and shading scenarios.

  4. Oral susceptibility of Singapore Aedes (Stegomyia aegypti (Linnaeus to Zika virus.

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    MeiZhi Irene Li

    Full Text Available Zika virus (ZIKV is a little known flavivirus that caused a major outbreak in 2007, in the South-western Pacific Island of Yap. It causes dengue-like syndromes but with milder symptoms. In Africa, where it was first isolated, ZIKV is mainly transmitted by sylvatic Aedes mosquitoes. The virus has also been isolated from Ae. aegypti and it is considered to be the vector involved in the urban transmission of the virus. Transmission of the virus by an African strain of Ae. aegypti has also been demonstrated under laboratory conditions. The aim of the present study is to describe the oral susceptibility of a Singapore strain of Ae. aegypti to ZIKV, under conditions that simulate local climate.To assess the receptivity of Singapore's Ae. aegypti to the virus, we orally exposed a local mosquito strain to a Ugandan strain of ZIKV. Upon exposure, fully engorged mosquitoes were maintained in an environmental chamber set at 29 °C and 70-75% RH. Eight mosquitoes were then sampled daily from day 1 to day 7, and subsequently on days 10 and 14 post exposure (pe. The virus titer of the midgut and salivary glands of each mosquito were determined using a tissue culture infectious dose(50 (TCID(50 assay. High midgut infection and salivary gland dissemination rates were observed. By day 5 after the infectious blood meal, ZIKV was found in the salivary glands of more than half of the mosquitoes tested (62%; and by day 10, all mosquitoes were potentially infective.This study showed that Singapore's urban Ae. aegypti are susceptible and are potentially capable of transmitting ZIKV. The virus could be established in Singapore should it be introduced. Nevertheless, Singapore's current dengue control strategy is applicable to control ZIKV.

  5. Excito-repellency of essential oils against an Aedes aegypti (L.) field population in Thailand.

    Science.gov (United States)

    Boonyuan, Wasana; Grieco, John P; Bangs, Michael J; Prabaripai, Atchariya; Tantakom, Siripun; Chareonviriyaphap, Theeraphap

    2014-06-01

    An investigation of the behavioral responses of Aedes aegypti (= Stegomyia aegypti) to various concentrations of essential oils (2.5, 5, and 10%) extracted from hairy basil (Ocimum americanum Linn), ginger (Zingiber officinale Roscoe), lemongrass (Cymbopogon citratus Stapf), citronella grass (Cymbopogon nardus Rendle), and plai (Zingiber cassumunar Roxb) were performed using an excito-repellency test chamber. Results showed that Ae. aegypti exhibited varying levels of escape response in both the contact and noncontact chambers in response to different essential oils. The magnitude of the behaviors changed in a dose-response fashion depending on the percent volume to volume concentration of oil used. A 2.5% concentration of hairy basil oil produced a significantly greater escape response compared to the other extracts at the same concentration (P< 0.05). Oils of ginger, lemongrass, and citronella produced stronger irritant and repellent responses at the median 5% concentration compared to the lowest and highest concentrations. There was marked suppression of escape for both contact and noncontact tests using 10% concentrations of hairy basil, lemongrass, and citronella, with high knockdown for all three oils after 30 min. Hairy basil and lemongrass had the highest insecticidal activity to Ae. aegypti, with LC50 values of 6.3 and 6.7 percent, respectively. We conclude that the essential oils from native plants tested, and likely many other extracts found in plants, have inherent repellent and irritant qualities that should to be screened and optimized for their behavior-modifying properties against Ae. aegypti and other biting arthropods of public health and pest importance. PMID:24820563

  6. Spatial patterns of high Aedes aegypti oviposition activity in northwestern Argentina.

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    Elizabet Lilia Estallo

    Full Text Available BACKGROUND: In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. METHODOLOGY: Oviposition activity was detected in Orán City (Salta province using ovitraps, weekly replaced (October 2005-2007. Spatial autocorrelation was measured with Moran's Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. PRINCIPAL FINDINGS: Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC=0.77, obtaining 99% of sensitivity and 75.29% of specificity. CONCLUSIONS: Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist

  7. The wMel Strain of Wolbachia Reduces Transmission of Chikungunya Virus in Aedes aegypti

    Science.gov (United States)

    Aliota, Matthew T.; Walker, Emma C.; Uribe Yepes, Alexander; Dario Velez, Ivan; Christensen, Bruce M.; Osorio, Jorge E.

    2016-01-01

    Background New approaches to preventing chikungunya virus (CHIKV) are needed because current methods are limited to controlling mosquito populations, and they have not prevented the invasion of this virus into new locales, nor have they been sufficient to control the virus upon arrival. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against CHIKV. Although this approach holds much promise for limiting virus transmission, at present our understanding of the ability of CHIKV to infect, disseminate, and be transmitted by wMel-infected Ae. aegypti currently being used at Wolbachia release sites is limited. Methodology/Principal Findings Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for CHIKV, even with extremely high viral titers in the bloodmeal. In addition, we examined the dynamics of CHIKV infection over the course of four to seven days post feeding. Wolbachia-infected mosquitoes remained non-infective over the duration of seven days, i.e., no infectious virus was detected in the saliva when exposed to bloodmeals of moderate viremia, but CHIKV-exposed, wild type mosquitoes did have viral loads in the saliva consistent with what has been reported elsewhere. Finally, the presence of wMel infection had no impact on the lifespan of mosquitoes as compared to wild type mosquitoes following CHIKV infection. Conclusions/Significance These results could have an impact on vector control strategies in areas where Ae. aegypti are transmitting both DENV and CHIKV; i.e., they argue for further exploration, both in the laboratory and the field, on the feasibility of expanding this

  8. Screening of Methanolic Plant Extracts against Larvae of Aedes aegypti and Anopheles stephensi in Mysore

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    Thirumalapura Krishnaiah Mohankumar

    2016-01-01

    Full Text Available Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anoph­eles stephensi to a series of concentrations of the methanolic extracts.Methods: Susceptibility tests on Ae. aegypti and An. stephensi were conducted using standard WHO methods. The larvae of two mosquito species were exposed to methanolic extracts and mortality counts were made after 24 hours of exposure as per WHO method. Larvae of Ae. aegypti were more susceptible than that of An. stephensi.Results: Among the nine plant species tested, Annona reticulata leaf extract was more effective against Ae. aegypti larvae with LC50 and LC90 values of 95.24 and 262.64 ppm respectively and against An. stephensi larvae 262.71 and 636.94 ppm respectively. The least efficacy was in Cosmos bipinnatus with LC50 and LC90 values of 442.6 and 1225.93 ppm against Ae. aegypti and LC50 and LC90 values of 840.69 and 1334.01 ppm of Thespesia populnea against An. stephensi.Conclusion: The crude methanolic extract of the An. reticulata with good larvicidal efficacy could be considered for further characterization to control mosquito vectors instead of chemical insecticides. High efficacy found in An. re­ticulata extract will be considered for further studies to isolate the bioactive compound.

  9. Genetic Diversity and Phylogeny of Aedes aegypti, the Main Arbovirus Vector in the Pacific.

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    Elodie Calvez

    2016-01-01

    Full Text Available The Pacific region is an area unique in the world, composed of thousands of islands with differing climates and environments. The spreading and establishment of the mosquito Aedes aegypti in these islands might be linked to human migration. Ae. aegypti is the major vector of arboviruses (dengue, chikungunya and Zika viruses in the region. The intense circulation of these viruses in the Pacific during the last decade led to an increase of vector control measures by local health authorities. The aim of this study is to analyze the genetic relationships among Ae. aegypti populations in this region.We studied the genetic variability and population genetics of 270 Ae. aegypti, sampled from 9 locations in New Caledonia, Fiji, Tonga and French Polynesia by analyzing nine microsatellites and two mitochondrial DNA regions (CO1 and ND4. Microsatellite markers revealed heterogeneity in the genetic structure between the western, central and eastern Pacific island countries. The microsatellite markers indicate a statistically moderate differentiation (FST = 0.136; P < = 0.001 in relation to island isolation. A high degree of mixed ancestry can be observed in the most important towns (e.g. Noumea, Suva and Papeete compared with the most isolated islands (e.g. Ouvea and Vaitahu. Phylogenetic analysis indicated that most of samples are related to Asian and American specimens.Our results suggest a link between human migrations in the Pacific region and the origin of Ae. aegypti populations. The genetic pattern observed might be linked to the island isolation and to the different environmental conditions or ecosystems.

  10. Aedes aegypti uses RNA interference in defense against Sindbis virus infection

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    Wilusz Jeffrey

    2008-03-01

    Full Text Available Abstract Background RNA interference (RNAi is an important anti-viral defense mechanism. The Aedes aegypti genome encodes RNAi component orthologs, however, most populations of this mosquito are readily infected by, and subsequently transmit flaviviruses and alphaviruses. The goal of this study was to use Ae. aegypti as a model system to determine how the mosquito's anti-viral RNAi pathway interacts with recombinant Sindbis virus (SINV; family Togaviridae, genus Alphavirus. Results SINV (TR339-eGFP (+ strand RNA, infectious virus titers and infection rates transiently increased in mosquitoes following dsRNA injection to cognate Ago2, Dcr2, or TSN mRNAs. Detection of SINV RNA-derived small RNAs at 2 and 7 days post-infection in non-silenced mosquitoes provided important confirmation of RNAi pathway activity. Two different recombinant SINV viruses (MRE16-eGFP and TR339-eGFP with significant differences in infection kinetics were used to delineate vector/virus interactions in the midgut. We show virus-dependent effects on RNAi component transcript and protein levels during infection. Monitoring midgut Ago2, Dcr2, and TSN transcript levels during infection revealed that only TSN transcripts were significantly increased in midguts over blood-fed controls. Ago2 protein levels were depleted immediately following a non-infectious bloodmeal and varied during SINV infection in a virus-dependent manner. Conclusion We show that silencing RNAi components in Ae. aegypti results in transient increases in SINV replication. Furthermore, Ae. aegypti RNAi is active during SINV infection as indicated by production of virus-specific siRNAs. Lastly, the RNAi response varies in a virus-dependent manner. These data define important features of RNAi anti-viral defense in Ae. aegypti.

  11. Sitios de Cría del Aedes aegypti en la Provincia de Limón, Costa Rica Breeding sites of Aedes aegypti in the province of Limón, Costa Rica

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    Rodrigo Marín Rodríguez

    2012-06-01

    Full Text Available En Costa Rica el dengue constituye la principal enfermedad de transmisión vectorial. Su control requiere un conocimiento integral de su vector Aedes aegypti, el cual utiliza gran variedad de recipientes artificiales para su cría. Objetivos: Identificar y describir los principales sitios de cría del A. aegypti en la provincia de Limón. Materiales y Métodos: El muestreo se realizó por el personal del programa de control de vectores durante el año 2011; de forma simultánea en los seis cantones que conforman la provincia de Limón. Resultados: Se identifico la presencia de A. aegypti en los seis cantones de la provincia de Limón. Los sitios de cría mas frecuentes fueron las llantas, los tarros o depósitos inservibles, los baldes y los tanques. Conclusiones: La proliferación del A. aegypti está directamente relacionado con el hombre, sus malos hábitos, y por la calidad de los servicios de salud de protección y mejoramiento del ambiente humano. Estos resultados demuestran que el abordaje del control del A. aegypti debe ser integral.Dengue is the main disease due to vectorial transmission in Costa Rica. Its control requires comprehensive knowledge of its vector which uses a wide variety of artificial containers for breeding. Objectives: To identify and describe Aedes aegypti breeding sites present in the Limon province of Costa Rica. Materials and methods: this survey was carried out during the year 2011 by personnel of the Vector Control Program working simultaneously in six municipalities of the studied region. Results: We identified the presence of Aedes aegypti in six municipalities in the province of Limon. The most frequent breeding sites were tires, cans or unusable deposits, buckets and tanks. Conclusions: Proliferation of Aedes aegypti is directly related to man, his bad habits, and to the quality of health care models regarding protection and improvement of the human environment. These results show that the approach to

  12. Spatial and temporal patterns in pupal and adult production of the dengue vector Aedes aegypti in Kamphaeng Phet, Thailand

    NARCIS (Netherlands)

    Koenraadt, C.J.M.; Aldstadt, J.; Kijchalao, U.; Sithiprasasna, R.; Getis, A.; Jones, J.W.; Scott, T.W.

    2008-01-01

    We investigated how temporal and spatial effects confound the functional relationship between pupal and adult populations of Aedes aegypti and thus the value of pupal numbers as predictors of dengue transmission risk in Kamphaeng Phet, Thailand. We found considerable seasonal shifts in productivity

  13. Spatial distribution and esterase activity in populations of Aedes (Stegomyia aegypti (Linnaeus (Diptera: Culicidae resistant to temephos

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    Wanessa Porto Tito Gambarra

    2013-04-01

    Full Text Available INTRODUCTION: The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypti collected in municipalities of the State of Paraíba. METHODS: Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a./L and multiple concentrations that caused mortalities between 5% and 99%. Electrophoresis of isoenzymes was used to verify the patterns of esterase activity among populations of the vector. RESULTS: All populations of Aedes aegypti were resistant to temephos, presenting a resistance rate (RR greater than 20. The greatest lethal dose 50% of the sample (CL50 was found for the municipality of Lagoa Seca, approximately forty-one times the value of CL50 for the Rockefeller population. The populations characterized as resistant showed two to six regions of α and β-esterase, called EST-1 to EST-6, while the susceptible population was only seen in one region of activity. CONCLUSIONS: Aedes aegypti is widely distributed and shows a high degree of resistance to temephos in all municipalities studied. In all cases, esterases are involved in the metabolism and, consequently, in the resistance to temephos.

  14. The potential attractant or repellent effects of different water types on oviposition in Aedes aegypti L. (Dipt., Culicidae)

    NARCIS (Netherlands)

    Navarro, D.M.A.F.; Oliveira, de P.E.S.; Potting, R.P.J.; Brito, A.C.; Fital, S.J.F.; Goulart Sant Ana, A.E.

    2003-01-01

    The selection of oviposition sites by the yellow-fever mosquito, Aedes aegypti , was studied in the laboratory. The repellent or attractant effects of salinity and the presence of bacteria in water collected from a local community on the Brazilian coast were investigated. Water contaminated with bac

  15. Spatial distribution and esterase activity in populations of Aedes (Stegomyia aegypti (Linnaeus (Diptera: Culicidae resistant to temephos

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    Wanessa Porto Tito Gambarra

    2013-09-01

    Full Text Available INTRODUCTION: The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypti collected in municipalities of the State of Paraíba. METHODS: Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a./L and multiple concentrations that caused mortalities between 5% and 99%. Electrophoresis of isoenzymes was used to verify the patterns of esterase activity among populations of the vector. RESULTS: All populations of Aedes aegypti were resistant to temephos, presenting a resistance rate (RR greater than 20. The greatest lethal dose 50% of the sample (CL50 was found for the municipality of Lagoa Seca, approximately forty-one times the value of CL50 for the Rockefeller population. The populations characterized as resistant showed two to six regions of α and β-esterase, called EST-1 to EST-6, while the susceptible population was only seen in one region of activity. CONCLUSIONS: Aedes aegypti is widely distributed and shows a high degree of resistance to temephos in all municipalities studied. In all cases, esterases are involved in the metabolism and, consequently, in the resistance to temephos.

  16. Papyracillic acid and its derivatives as biting deterrents against Aedes aegypti(Diptera: Culicidae): structure–activity relationships

    Science.gov (United States)

    Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Papyracillic acid, the main phytotoxin produced by Ascochyta agropyrina var. nana, was evaluated in a preliminary screening together with other fungal phytotoxins, cyclo...

  17. Microclimate and human factors in the divergent ecology of Aedes aegypti along the Arizona, U.S./Sonora, MX border.

    Science.gov (United States)

    Hayden, Mary H; Uejio, Christopher K; Walker, Kathleen; Ramberg, Frank; Moreno, Rafael; Rosales, Cecilia; Gameros, Mercedes; Mearns, Linda O; Zielinski-Gutierrez, Emily; Janes, Craig R

    2010-08-01

    This study examined the association of human and environmental factors with the presence of Aedes aegypti, the vector for dengue fever and yellow fever viruses, in a desert region in the southwest United States and northwest Mexico. Sixty-eight sites were longitudinally surveyed along the United States-Mexico border in Tucson, AZ, Nogales, AZ, and Nogales, Sonora during a 3-year period. Aedes aegypti presence or absence at each site was measured three times per year using standard oviposition traps. Maximum and minimum temperature and relative humidity were measured hourly at each site. Field inventories were conducted to measure human housing factors potentially affecting mosquito presence, such as the use of air-conditioning and evaporative coolers, outdoor vegetation cover, and access to piped water. The results showed that Ae. aegypti presence was highly variable across space and time. Aedes aegypti presence was positively associated with highly vegetated areas. Other significant variables included microclimatic differences and access to piped water. This study demonstrates the importance of microclimate and human factors in predicting Ae. aegypti distribution in an arid environment.

  18. DAMPAK FOGGING INSEKTISIDA MALATHION, FENDONA, CYNOFF DAN ICON TERHADAP ANGKA JENTIK NYAMUK Aedes aegypti

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    M. Hasyimi

    2012-09-01

    Full Text Available Insektisida malathion, fendona, cynoff dan icon adalah jenis insektisida yang sasarannya adalah nyamuk Aedes aegypti dewasa. Jumlah kematian nyamuk dewasa akan berdampak terhadap angka jentik. Penelitian lapangan berskala kecil untuk mengetahui dampaknya terhadap angka jentik yang terdiri Container index (CI, House index (HI dan Breteau index (BI telah dilakukan pada bulan Juni 2004. Penelitian dilakukan di Kelurahan Kramatjati Jakarta Timur pada RW yang berbeda-beda.Pengambilan data angka jentik dilakukan dengan single larva methode. Sehari sebelum penyemprotan dilakukan, diambil data angka jentik untuk mengetahui kepadatan awal. Pengambilan data setelah penyemprotan dilakukan pada 5 hari dan 11 hari kemudian. Hasil penelitian menunjukkan bahwa penyemprotan dengan malathion dapat menurunkan angka CIsebesar 7,3; HI sebesar 5,8% dan BI sebesar 11,2. Penyemprotan dengan fendona dapat menurunkan angka CI sebesar 4,7%; HI sebesar 6% dan BI sebesar 6 dari angka jentik 5 hari setelah penyemprotan. Sedangkan penyemprotan cynoff dan icon tidak menurunkan angka jentik sama sekali.   Kata kunci .Angkajentik Aedes aegypti, malathion .fendona, icon, cynoff

  19. Effects of gamma radiation on reproductive parameters of Aedes aegypti (L.) - a dengue vector

    International Nuclear Information System (INIS)

    Aedes aegypti is an important vector for dengue, dengue haemorrhagic fever and chikungunya. Such diseases have resurged in developing countries and are also emerging as clear threats for epidemic outbreaks in developed countries. The said species is one of the best-known insects from the standpoint of both basic and applied sciences. Because of its medical importance and as well emerged model organism for radiation/toxicology and biochemical studies. The purpose of the present study to evaluate the impact of various doses gamma radiation on Aedes aegypti including 1, 2, 3, 4, 6, 8, 10, 15, 20, 25, 30, 35, 40, 45 and 50 Gy on different reproductive parameters i.e. fecundity, hatchability, fertility, pupation for three generations. When the flies were exposed to 1 and 2 Gy did not show any change for the above said doses. However, changes observed in hatchability from 3 Gy onwards. Reduction in fecundity was observed after exposure to 8 Gy onwards. While considerable reduction in hatchability was observed when they are exposed to 30 to 50 Gy. Sterility increased from 5 to 98% as the dose increased from 3 to 50 Gy. Furthermore, reduction in pupation and adult emergence were observed as dose increases. Dose response curve for egg hatchability and fertility for three generations were constructed and presented. From the data, it has been shown that, radiation induced dominant lethal mutations cause cessation of development prior to egg hatchability although in some cases mortality was observed in larval or pupal stages. (author)

  20. Dengue Virus Infection of Aedes aegypti Requires a Putative Cysteine Rich Venom Protein.

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    Berlin Londono-Renteria

    2015-10-01

    Full Text Available Dengue virus (DENV is a mosquito-borne flavivirus that causes serious human disease and mortality worldwide. There is no specific antiviral therapy or vaccine for DENV infection. Alterations in gene expression during DENV infection of the mosquito and the impact of these changes on virus infection are important events to investigate in hopes of creating new treatments and vaccines. We previously identified 203 genes that were ≥5-fold differentially upregulated during flavivirus infection of the mosquito. Here, we examined the impact of silencing 100 of the most highly upregulated gene targets on DENV infection in its mosquito vector. We identified 20 genes that reduced DENV infection by at least 60% when silenced. We focused on one gene, a putative cysteine rich venom protein (SeqID AAEL000379; CRVP379, whose silencing significantly reduced DENV infection in Aedes aegypti cells. Here, we examine the requirement for CRVP379 during DENV infection of the mosquito and investigate the mechanisms surrounding this phenomenon. We also show that blocking CRVP379 protein with either RNAi or specific antisera inhibits DENV infection in Aedes aegypti. This work identifies a novel mosquito gene target for controlling DENV infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

  1. Breeding Sites of Aedes aegypti: Potential Dengue Vectors in Dire Dawa, East Ethiopia

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    Dejene Getachew

    2015-01-01

    Full Text Available Background and Objectives. Entomological survey was carried out from May-June to September-October 2014 to investigate the presence of dengue vectors in discarded tires and artificial water containers in houses and peridomestic areas. Methods. A cross-sectional immature stage survey was done indoors and outdoors in 301 houses. Mosquito larval sampling was conducted using pipette or dipper depending on container types. Larvae were identified morphologically and larval indices were also calculated. Results. A total of 750 containers were inspected, and of these 405 were positive for mosquito larvae. A total of 1,873 larvae were collected and morphologically identified as Aedes aegypti (n=1580: 84.4% and Culex (n=293: 15.6%. The larval indices, house index, container index, and breteau index, varied from 33.3 to 86.2, from 23.2 to 73.9, and from 56.5 to 188.9, respectively. Conclusion. Aedes aegypti is breeding in a wide range of artificial containers. To control these mosquitoes, the integration of different methods should be taken into consideration.

  2. Socioeconomic and Ecological Factors Influencing Aedes aegypti Prevalence, Abundance, and Distribution in Dhaka, Bangladesh.

    Science.gov (United States)

    Dhar-Chowdhury, Parnali; Haque, C Emdad; Lindsay, Robbin; Hossain, Shakhawat

    2016-06-01

    This study examined household risk factors and prevalence, abundance, and distribution of immature Aedes aegypti and Aedes albopictus, and their association with socioeconomic and ecological factors at urban zonal and household levels in the city of Dhaka, Bangladesh. During the 2011 monsoon, 826 households in 12 randomly selected administrative wards were surveyed for vector mosquitoes. Results revealed that the abundance and distribution of immature Ae. aegypti and Ae. albopictus, and pupae-per-person indices did not vary significantly among the zones with varied socioeconomic status. Of 35 different types of identified wet containers, 30 were infested, and among the 23 pupae-positive container types, nine were defined as the "most productive" for pupae including: disposable plastic containers (12.2% of 550), sealable plastic barrels (12.0%), tires (10.4%), abandoned plastic buckets (9.6%), flower tub and trays (8.5%), refrigerator trays (6.5%), plastic bottles (6.4%), clay pots (4.9%), and water tanks (1.6%). When the function of the containers was assessed, ornamental, discarded, and household repairing and reconstruction-related container categories were found significantly associated with the number of pupae in the households. The purpose of storing water and income variables were significant predictors of possession of containers that were infested by vector mosquitoes. PMID:27022149

  3. The combined action of phytolarvicides for the control of dengue fever vector, Aedes aegypti

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    Adelia Grzybowski

    2012-06-01

    Full Text Available Amongst other botanical sources, Annona muricata L., Annonaceae, seeds and Piper nigrum L., Piperaceae, fruits are particularly enriched with acetogenins and piperine-related amides, respectively. These crude ethanolic extracts are potent Aedes aegypti bioactives that can kill Aedes aegypti larvae (dengue fever mosquito. A. muricata displayed a 93.48 µg/mL LC50 and P. nigrum an 1.84 µg/mL LC50. An uncommon pharmacognostical/toxicological approach was used, namely different combinations of both extracts to achieve an improved lethal effect on the larvae. The independence test (χ² was utilized to evaluate the combination of the two crude extracts. All of the tested combinations behaved synergistically and these novel results were attributed to the completely different biochemical mechanisms of the differentiated chemical substances that were present in the two botanical sources. Besides the two above selected plants, Melia azedarach L., Meliaceae, Origanum vulgare L., Lamiaceae, and Ilex paraguariensis A. St.-Hil., Aquifoliaceae, in order of decreasing toxicity, may also be sought as potential extracts for the sake of synergic combinations.

  4. Association of insecticide use and alteration on Aedes aegypti susceptibility status

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    Maria de Lourdes da Graça Macoris

    2007-12-01

    Full Text Available Dengue and dengue hemorrhagic fever, vector-borne diseases transmitted by the mosquito Aedes aegypti, are presently important public health problems in Brazil. As the strategy for disease control is based on vector control through the use of insecticides, the development of resistance is a threat to programs efficacy. The objective of this study was to compare the Aedes aegypti susceptibility in nine vector populations from the state of São Paulo and seven from Northeast region of Brazil, since there was a difference on group of insecticide used between the areas. Bioassays with larvae and adult were performed according to the World Health Organization methods.The results showed higher resistance levels to organophosphates group in populations from the Northeast region where this group was used for both larvae and adult control than in São Paulo where organophosphates were used for larvae and pyretroids for adult control. Resistance to pyretroids in adults was widespread in São Paulo after ten years of use of cypermethrin while in vector populations from the Northeast region it was punctual. The difference in resistance profile between the areas is in accordance to the group of insecticide used.

  5. Alterations in the Aedes aegypti transcriptome during infection with West Nile, dengue and yellow fever viruses.

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    Tonya M Colpitts

    2011-09-01

    Full Text Available West Nile (WNV, dengue (DENV and yellow fever (YFV viruses are (reemerging, mosquito-borne flaviviruses that cause human disease and mortality worldwide. Alterations in mosquito gene expression common and unique to individual flaviviral infections are poorly understood. Here, we present a microarray analysis of the Aedes aegypti transcriptome over time during infection with DENV, WNV or YFV. We identified 203 mosquito genes that were ≥ 5-fold differentially up-regulated (DUR and 202 genes that were ≥ 10-fold differentially down-regulated (DDR during infection with one of the three flaviviruses. Comparative analysis revealed that the expression profile of 20 DUR genes and 15 DDR genes was quite similar between the three flaviviruses on D1 of infection, indicating a potentially conserved transcriptomic signature of flaviviral infection. Bioinformatics analysis revealed changes in expression of genes from diverse cellular processes, including ion binding, transport, metabolic processes and peptidase activity. We also demonstrate that virally-regulated gene expression is tissue-specific. The overexpression of several virally down-regulated genes decreased WNV infection in mosquito cells and Aedes aegypti mosquitoes. Among these, a pupal cuticle protein was shown to bind WNV envelope protein, leading to inhibition of infection in vitro and the prevention of lethal WNV encephalitis in mice. This work provides an extensive list of targets for controlling flaviviral infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

  6. Efficacy of photodynamic therapy against larvae of Aedes aegypti: confocal microscopy and fluorescence-lifetime imaging

    Science.gov (United States)

    de Souza, L. M.; Pratavieira, S.; Inada, N. M.; Kurachi, C.; Corbi, J.; Guimarães, F. E. G.; Bagnato, V. S.

    2014-03-01

    Recently a few demonstration on the use of Photodynamic Reaction as possibility to eliminate larvae that transmit diseases for men has been successfully demonstrated. This promising tool cannot be vastly used due to many problems, including the lake of investigation concerning the mechanisms of larvae killing as well as security concerning the use of photosensitizers in open environment. In this study, we investigate some of the mechanisms in which porphyrin (Photogem) is incorporated on the Aedes aegypti larvae previously to illumination and killing. Larvae at second instar were exposed to the photosensitizer and after 30 minutes imaged by a confocal fluorescence microscope. It was observed the presence of photosensitizer in the gut and at the digestive tract of the larva. Fluorescence-Lifetime Imaging showed greater photosensitizer concentration in the intestinal wall of the samples, which produces a strong decrease of the Photogem fluorescence lifetime. For Photodynamic Therapy exposition to different light doses and concentrations of porphyrin were employed. Three different light sources (LED, Fluorescent lamp, Sun light) also were tested. Sun light and fluorescent lamp shows close to 100% of mortality after 24 hrs. of illumination. These results indicate the potential use of photodynamic effect against the LARVAE of Aedes aegypti.

  7. Aedes aegypti and Aedes albopictus (Diptera: Culicidae: coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization Aedes aegypti e Aedes albopictus (Diptera: Culicidae: coexistência e susceptibilidade ao temephos, em municípios com ocorrência de casos de dengue e diferentes características de urbanização

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2011-06-01

    Full Text Available INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion. Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina presented survival when exposed to the organophosphate temephos.INTRODUÇÃO: O presente estudo teve como objetivo verificar a coexistência de populações de Aedes aegypti e de Aedes albopictus em municípios do Estado do Paraná e Santa Catarina com diferentes formas de urbanização, onde ocorrem casos de dengue, e avaliar a susceptibilidade ao organofosforado temephos. MÉTODOS: O número de ovos por ovitrampa foram contados (sem distinguir a espécie e colocados para eclosão e posterior identificação das espécies. A análise das populacões foi conduzida para determinar aleatoriedade e agregação usando a razão variância/média (índice de dispersão. A susceptibilidade ao

  8. Field trial on a novel control method for the dengue vector, Aedes aegypti by the systematic use of Olyset® Net and pyriproxyfen in Southern Vietnam

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    Tsunoda Takashi

    2013-01-01

    Full Text Available Abstract Background Jars, tanks, and drums provide favorable rearing/breeding sites for Aedes aegypti in Vietnam. However, the use of insecticides to control mosquitoes at such breeding sites has not been approved in Vietnam since they are also often sources of drinking water, making larval vector control difficult. Mosquito nets pre-treated with long-lasting insecticide treated nets (LLITNs form an effective measure for malaria control. We examined changes in the abundance of immature Aedes aegypti to evaluate the efficacy of covering ceramic jars with lids comprising one type of LLITN, Olyset® Net, in inhibiting oviposition by adult females, and to evaluate the effect of treating other breeding containers, such as flower vases, inside and around the outside of houses with a slow-release pyriproxyfen formulation to kill pupae. Methods We selected 313 households for the trial and 363 households for the control in Tan Chanh, Long An province, Vietnam. In the trial area, Olyset® Net lids were used to cover five major types of water container (ceramic jars, cylindrical concrete tanks, other concrete tanks, plastic drums, and plastic buckets, while pyriproxyfen was used to treat flower vases and ant traps. We also monitored dengue virus transmission by measuring anti-dengue IgM and IgG levels in healthy residents in both control and trial areas to estimate the effectiveness of Olyset® Net at controlling the dengue vector, Aedes aegypti. Results The container-index and house-index for immature Ae. aegypti fell steeply one month after treatment in the trial area. Lids with Olyset® Net that fit container openings clearly seemed to reduce the presence of immature Ae. aegypti as the density of pupae decreased 1 month after treatment in the trial area. Pyriproxyfen was also effective at killing pupae in the water containers in the trial area. Although the dengue seroconversion rate was not influenced by Olyset® Net, it was lower in two-five year old

  9. Maya Index and Larva Density Aedes Aegypti Toward Dengue Infection

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    Sang G. Purnama

    2012-12-01

    Full Text Available South Denpasar District was of there as with the highest dengue cases in Bali province. The number of mosquito breeding places and larvae density become risk factor that influenced the spreading of mosquitoes. Maya index was an indicator to measure the amount of waterreservoirs can be breeding places for mosquitoes. Knowing the relationship between maya index and density of larvae and pupae of Ae.aegypti toward dengue infection in South Denpasar District. The study was observational analytic with case-control design. Data was collected through interviews and field observations to 150 respondents. The survey entomologist with indicators maya index, house index (HI, container index (CI, breteau index (BI and pupa index (PI to see the density of larvae and pupae in survey area. Dengue transmission risk was categorized mild, moderate and severe based on density figure. Water storage containers inspected in 1215 containers that as many as 675 containers in the case and 540 containers in control. Water reservoirs (TPA that the most larvae was tub (29.27%, dispenser (18.29%, container tirta (10.98%, wells (10.98%. Maya index status was lower in the case (24% smaller thancontrols (37.33%. Value of HI = 23.33; CI=10.69; BI=55; PI=15.33. Based on HI and CI indicator South Denpasar District means have moderate the risk of transmission spread of dengue disease. Based on the BI, have a high risk of transmission to the spread of dengue disease. Based on the maya index showed house cases have highest risk as breeding place compare than control house. House index, Breteau index, container index, pupa index and maya index have correlation with dengue infection. Kind of breeding place have the high risk is bath tub

  10. Aedes aegypti and Aedes albopictus (Diptera: Culicidae): coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization Aedes aegypti e Aedes albopictus (Diptera: Culicidae): coexistência e susceptibilidade ao temephos, em municípios com ocorrência de casos de dengue e diferentes características de urbanização

    OpenAIRE

    Josiane Somariva Prophiro; Onilda Santos Silva; Jonny Edward Duque Luna; Carla Fernanda Piccoli; Luiz Alberto Kanis; Mario Antonio Navarro da Silva

    2011-01-01

    INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggr...

  11. Genomic organization and splicing evolution of the doublesex gene, a Drosophila regulator of sexual differentiation, in the dengue and yellow fever mosquito Aedes aegypti

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    Arcà Bruno

    2011-02-01

    Full Text Available Abstract Background In the model system Drosophila melanogaster, doublesex (dsx is the double-switch gene at the bottom of the somatic sex determination cascade that determines the differentiation of sexually dimorphic traits. Homologues of dsx are functionally conserved in various dipteran species, including the malaria vector Anopheles gambiae. They show a striking conservation of sex-specific regulation, based on alternative splicing, and of the encoded sex-specific proteins, which are transcriptional regulators of downstream terminal genes that influence sexual differentiation of cells, tissues and organs. Results In this work, we report on the molecular characterization of the dsx homologue in the dengue and yellow fever vector Aedes aegypti (Aeadsx. Aeadsx produces sex-specific transcripts by alternative splicing, which encode isoforms with a high degree of identity to Anopheles gambiae and Drosophila melanogaster homologues. Interestingly, Aeadsx produces an additional novel female-specific splicing variant. Genomic comparative analyses between the Aedes and Anopheles dsx genes revealed a partial conservation of the exon organization and extensive divergence in the intron lengths. An expression analysis showed that Aeadsx transcripts were present from early stages of development and that sex-specific regulation starts at least from late larval stages. The analysis of the female-specific untranslated region (UTR led to the identification of putative regulatory cis-elements potentially involved in the sex-specific splicing regulation. The Aedes dsx sex-specific splicing regulation seems to be more complex with the respect of other dipteran species, suggesting slightly novel evolutionary trajectories for its regulation and hence for the recruitment of upstream splicing regulators. Conclusions This study led to uncover the molecular evolution of Aedes aegypti dsx splicing regulation with the respect of the more closely related Culicidae

  12. Effect of Moringa oleifera flower extract on larval trypsin and acetylcholinesterase activities in Aedes aegypti.

    Science.gov (United States)

    Pontual, Emmanuel Viana; Napoleão, Thiago Henrique; Dias de Assis, Caio Rodrigo; de Souza Bezerra, Ranilson; Xavier, Haroudo Satiro; Navarro, Daniela Maria do Amaral Ferraz; Coelho, Luana Cassandra Breitenbach Barroso; Paiva, Patrícia Maria Guedes

    2012-03-01

    Aedes aegypti control is crucial to reducing dengue fever. Aedes aegypti larvae have developed resistance to organophosporous insecticides and the use of natural larvicides may help manage larval resistance by increasing elements in insecticide rotation programs. Here, we report on larvicidal activity of Moringa oleifera flower extract against A. aegypti L(1), L(2), L(3), and L(4) as well as the effect of flower extract on gut trypsin and whole-larval acetylcholinesterase from L(4.) In addition, the heated flower extract was investigated for larvicidal activity against L(4) and effect on larval gut trypsin. Moringa oleifera flower extract contains a proteinaceous trypsin inhibitor (M. oleifera flower trypsin inhibitor, MoFTI), triterpene (β-amyrin), sterol (β-sitosterol) as well as flavonoids (kaempferol and quercetin). Larvicidal activity was detected against L(2), L(3), and L(4) (LC(50) of 1.72%, 1.67%, and 0.92%, respectively). Flower extract inhibited L(4) gut trypsin (MoFTI K(i) = 0.6 nM) and did not affect acetylcholinesterase activity. In vivo assay showed that gut trypsin activity from L(4) treated with M. oleifera flower extract decreased over time (0-1,440 min) and was strongly inhibited (98.6%) after 310 min incubation; acetylcholinesterase activity was not affected. Thermal treatment resulted in a loss of trypsin inhibitor and larvicidal activities, supporting the hypothesis that flower extract contains a proteinaceous trypsin inhibitor that may be responsible for the deleterious effects on larval mortality. PMID:22392801

  13. Climate change and the potential global distribution of Aedes aegypti: spatial modelling using GIS and CLIMEX.

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    Khormi, Hassan M; Kumar, Lalit

    2014-05-01

    We examined the potential added risk posed by global climate change on the dengue vector Aedes aegypti abundance using CLIMEX, a powerful tool for exploring the relationship between the fundamental and realised niche of any species. After calibrating the model using data from several knowledge domains, including geographical distribution records, we estimated potential distributions of the mosquito under current and future potential scenarios. The impact of climate change on its potential distribution was assessed with two global climate models, the CSIRO-Mk3.0 and the MIROC-H, run with two potential, future emission scenarios (A1B and A2) published by the Intergovernmental Panel on Climate Change. We compared today's climate situation with two arbitrarily chosen future time points (2030 and 2070) to see the impact on the worldwide distribution of A. aegypti . The model for the current global climate indicated favourable areas for the mosquito within its known distribution in tropical and subtropical areas. However, even if much of the tropics and subtropics will continue to be suitable, the climatically favourable areas for A. aegypti globally are projected to contract under the future scenarios produced by these models, while currently unfavourable areas, such as inland Australia, the Arabian Peninsula, southern Iran and some parts of North America may become climatically favourable for this mosquito species. The climate models for the Aedes dengue vector presented here should be useful for management purposes as they can be adapted for decision/making regarding allocation of resources for dengue risk toward areas where risk infection remains and away from areas where climatic suitability is likely to decrease in the future. PMID:24893017

  14. Expansión del Aedes aegypti a localidades rurales de Cajamarca

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    Lucinda Troyes R

    2006-07-01

    Full Text Available Objetivos: Determinar la presencia, magnitud y expansión de Aedes aegypti en las localidades rurales de las provincias de Jaén y San Ignacio, departamento de Cajamarca. Materiales y métodos: Estudio transversal realizado entre abril y mayo de 2004, en 21 (100% localidades rurales ubicadas en las márgenes de la carretera Jaén-San Ignacio y al interior de ella, hasta en 90 minutos. Se inspeccionó recipientes de 1460 viviendas para la búsqueda de larvas y adultos del mosquito, se determinaron los índices aédicos, de recipiente y de Breteau. Resultados: Se demostró la presencia de Aedes aegypti en tres localidades rurales de la provincia de Jaén y en cuatro de la provincia de San Ignacio. Los índices aédicos variaron de 1,2 a 16,6%. Los recipientes infestados con mayor frecuencia fueron las llantas y los artículos en desuso. Conclusiones: Se reporta la expansión de A. aegypti en la tercera parte de localidades rurales de las provincias de Jaén y San Ignacio; esta expansión necesita ser más estudiada y considerada al implementarse las estrategias de prevención y control del dengue en la DISA Jaén, para evitar la aparición de brotes de dengue clásico, dengue hemorrágico, incluso fiebre amarilla urbana.

  15. Identification of carboxylesterase genes implicated in temephos resistance in the dengue vector Aedes aegypti.

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    Rodolphe Poupardin

    2014-03-01

    Full Text Available BACKGROUND: Thailand is currently experiencing one of its worst dengue outbreaks in decades. As in most countries where this disease is endemic, dengue control in Thailand is largely reliant on the use of insecticides targeting both immature and adult stages of the Aedes mosquito, with the organophosphate insecticide, temephos, being the insecticide of choice for attacking the mosquito larvae. Resistance to temephos was first detected in Aedes aegypti larvae in Thailand approximately 25 years ago but the mechanism responsible for this resistance has not been determined. PRINCIPAL FINDINGS: Bioassays on Ae. aegypti larvae from Thailand detected temephos resistance ratios ranging from 3.5 fold in Chiang Mai to nearly 10 fold in Nakhon Sawan (NS province. Synergist and biochemical assays suggested a role for increased carboxylesterase (CCE activities in conferring temephos resistance in the NS population and microarray analysis revealed that the CCE gene, CCEae3a, was upregulated more than 60 fold in the NS population compared to the susceptible population. Upregulation of CCEae3a was shown to be partially due to gene duplication. Another CCE gene, CCEae6a, was also highly regulated in both comparisons. Sequencing and in silico structure prediction of CCEae3a showed that several amino acid polymorphisms in the NS population may also play a role in the increased resistance phenotype. SIGNIFICANCE: Carboxylesterases have previously been implicated in conferring temephos resistance in Ae aegypti but the specific member(s of this family responsible for this phenotype have not been identified. The identification of a strong candidate is an important step in the development of new molecular diagnostic tools for management of temephos resistant populations and thus improved control of dengue.

  16. PENGARUH PENYULUHAN TERHADAP TINGKAT PENGET MASYARAKAT DAN KEPADATAN Aedes aegypti DI KECAMATAN BAYAH, PROVINSI BANTEN

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    Agnes Kurniawan

    2010-12-01

    Full Text Available The Effect of Health Education to Community Knowledge and Aedes aegypti Density in Bayah Subdistrict, Banten Province. Dengue Haemorrhagic Fever (DHF is a public health problem in Bayah, Banten Province thus, control of mosquitoes breeding sites (CMBS and health education is necessary. This study aimed to evaluate the effect of health education on people’s level of knowledge on CMBS and the density of Ae. aegypti. This study involved 106 villagers from Bayah in August (pretest and October (postest 2009. Data was collected through questionnaires, followed by observation of containers available in the house using single larval method and identified microscopically. Data was analyzed using marginal homogeneity test. The result showed, 64.2% and 1.3% villagers had poor and good knowledge on CMBS. This finding was in accordance to their education level and socio-economic status. After education, there were 14% had good and 54% poor knowledge (p = 0,001. Container index (CI and house index (HI were 18% and 52% respectively, suggesting high density of Ae. aegypti in that area. Following health education, CI and HI became 16% and 42% which were still above WHO level of indicator; which gave no significant difference in CI (p =0,523 and HI (p = 0,174. In conclusion, the level of knowledge increased after health education which was not followed by significant decrease in vector density, suggesting Bayah is still categorized as highly transmitted area of DHF.

  17. Spatial and temporal country-wide survey of temephos resistance in Brazilian populations of Aedes aegypti.

    Science.gov (United States)

    Chediak, Mateus; G Pimenta, Fabiano; Coelho, Giovanini E; Braga, Ima A; Lima, José Bento P; Cavalcante, Karina Ribeiro Lj; Sousa, Lindemberg C de; Melo-Santos, Maria Alice V de; Macoris, Maria de Lourdes da G; Araújo, Ana Paula de; Ayres, Constância Flávia J; Andrighetti, Maria Teresa M; Gomes, Ricristhi Gonçalves de A; Campos, Kauara B; Guedes, Raul Narciso C

    2016-05-01

    The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites. PMID:27143489

  18. Dengue virus type 2 infections of Aedes aegypti are modulated by the mosquito's RNA interference pathway.

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    Irma Sánchez-Vargas

    2009-02-01

    Full Text Available A number of studies have shown that both innate and adaptive immune defense mechanisms greatly influence the course of human dengue virus (DENV infections, but little is known about the innate immune response of the mosquito vector Aedes aegypti to arbovirus infection. We present evidence here that a major component of the mosquito innate immune response, RNA interference (RNAi, is an important modulator of mosquito infections. The RNAi response is triggered by double-stranded RNA (dsRNA, which occurs in the cytoplasm as a result of positive-sense RNA virus infection, leading to production of small interfering RNAs (siRNAs. These siRNAs are instrumental in degradation of viral mRNA with sequence homology to the dsRNA trigger and thereby inhibition of virus replication. We show that although dengue virus type 2 (DENV2 infection of Ae. aegypti cultured cells and oral infection of adult mosquitoes generated dsRNA and production of DENV2-specific siRNAs, virus replication and release of infectious virus persisted, suggesting viral circumvention of RNAi. We also show that DENV2 does not completely evade RNAi, since impairing the pathway by silencing expression of dcr2, r2d2, or ago2, genes encoding important sensor and effector proteins in the RNAi pathway, increased virus replication in the vector and decreased the extrinsic incubation period required for virus transmission. Our findings indicate a major role for RNAi as a determinant of DENV transmission by Ae. aegypti.

  19. Spatial genetic structure of Aedes aegypti mosquitoes in mainland Southeast Asia.

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    Hlaing, Thaung; Tun-Lin, Willoughby; Somboon, Pradya; Socheat, Duong; Setha, To; Min, Sein; Thaung, Sein; Anyaele, Okorie; De Silva, Babaranda; Chang, Moh Seng; Prakash, Anil; Linton, Yvonne; Walton, Catherine

    2010-07-01

    Aedes aegypti mosquitoes originated in Africa and are thought to have spread recently to Southeast Asia, where they are the major vector of dengue. Thirteen microsatellite loci were used to determine the genetic population structure of A. aegypti at a hierarchy of spatial scales encompassing 36 sites in Myanmar, Cambodia and Thailand, and two sites in Sri Lanka and Nigeria. Low, but significant, genetic structuring was found at all spatial scales (from 5 to >2000 km) and significant F IS values indicated genetic structuring even within 500 m. Spatially dependent genetic-clustering methods revealed that although spatial distance plays a role in shaping larger-scale population structure, it is not the only factor. Genetic heterogeneity in major port cities and genetic similarity of distant locations connected by major roads, suggest that human transportation routes have resulted in passive long-distance migration of A. aegypti. The restricted dispersal on a small spatial scale will make localized control efforts and sterile insect technology effective for dengue control. Conversely, preventing the establishment of insecticide resistance genes or spreading refractory genes in a genetic modification strategy would be challenging. These effects on vector control will depend on the relative strength of the opposing effects of passive dispersal. PMID:25567928

  20. Larvicidal activity of the essential oil from Lippia sidoides cham. against Aedes aegypti linn

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    Carvalho Ana Fontenele Urano

    2003-01-01

    Full Text Available The aim of this work was to study the larvicidal activity of Lippia sidoides essential oil against Aedes aegypti larvae. The essential oil and its hydrolate (saturated solution of essential oil in water were obtained by vapor extraction and their chemical composition determined by GL-chromatography coupled to mass spectroscopy. Bioassays were run with the essential oil, pure and diluted hydrolate and with their main constituents thymol and carvacrol. The results obtained showed that L. sidoides essential oil and its hydrolate have larvicidal action against the mosquito A. aegypti, causing an almost instantaneous mortality. Thymol, an alkylated phenol derivative and one of the major components of L. sidoides essential oil, was identified as the active principle responsible for the larvicidal action, causing 100% larval mortality at the lowest tested concentration of 0.017% (w/v. These results suggest that the essential oil of L. sidoides is promising as larvicide against A. aegypti and could be useful in the search of newer, more selective, and biodegradable larvicidal natural compounds to be used in official combat programs and at home.

  1. Silencing of P-glycoprotein increases mortality in temephos-treated Aedes aegypti larvae.

    Science.gov (United States)

    Figueira-Mansur, J; Ferreira-Pereira, A; Mansur, J F; Franco, T A; Alvarenga, E S L; Sorgine, M H F; Neves, B C; Melo, A C A; Leal, W S; Masuda, H; Moreira, M F

    2013-12-01

    Re-emergence of vector-borne diseases such as dengue and yellow fever, which are both transmitted by the Aedes aegypti mosquito, has been correlated with insecticide resistance. P-glycoproteins (P-gps) are ATP-dependent efflux pumps that are involved in the transport of substrates across membranes. Some of these proteins have been implicated in multidrug resistance (MDR). In this study, we identified a putative P-glycoprotein in the Ae. aegypti database based on its significantly high identity with Anopheles gambiae, Culex quinquefasciatus, Drosophila melanogaster and human P-gps. The basal ATPase activity of ATP-binding cassette transporters in larvae was significantly increased in the presence of MDR modulators (verapamil and quinidine). An eightfold increase in Ae. aegypti P-gp (AaegP-gp) gene expression was detected in temephos-treated larvae as determined by quantitative PCR. To analyse the potential role of AaegP-gp in insecticide efflux, a temephos larvicide assay was performed in the presence of verapamil. The results showed an increase of 24% in temephos toxicity, which is in agreement with the efflux reversing effect. RNA interference (RNAi)-mediated silencing of the AaegP-gp gene caused a significant increase in temephos toxicity (57%). In conclusion, we have demonstrated for the first time in insects that insecticide-induced P-gp expression can be involved in the modulation of insecticide efflux.

  2. Biosynthesis of silver nanoparticles using Bacillus thuringiensis against dengue vector, Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Banu, A Najitha; Balasubramanian, C; Moorthi, P Vinayaga

    2014-01-01

    The present study reveals the larvicidal activity of silver nanoparticles (AgNPs) synthesized by Bacillus thuringiensis (Bt) against Aedes aegypti responsible for the diseases of public health importance. The Bt-AgNPs were characterized by using UV-visible spectrophotometer followed by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy. A surface plasmon resonance spectrum of AgNps was obtained at 420 nm. The particle sizes were measured through SEM imaging ranging from 43.52 to 142.97 nm. The Bt-AgNPs has also given a characteristic peak at 3 keV in EDX image. Interestingly, the mortality rendered by Bt-AgNPs was comparatively high than that of the control against third-instar larvae of A. aegypti (LC50 0.10 ppm and LC90 0.39 ppm) in all the tested concentrations, viz. 0.03, 0.06, 0.09, 0.12, and 0.15 ppm. Hence, Bt-AgNPs would be significantly used as a potent mosquito larvicide against A. aegypti.

  3. Spatial and temporal country-wide survey of temephos resistance in Brazilian populations of Aedes aegypti

    Science.gov (United States)

    Chediak, Mateus; G Pimenta, Fabiano; Coelho, Giovanini E; Braga, Ima A; Lima, José Bento P; Cavalcante, Karina Ribeiro LJ; de Sousa, Lindemberg C; de Melo-Santos, Maria Alice V; Macoris, Maria de Lourdes da G; de Araújo, Ana Paula; Ayres, Constância Flávia J; Andrighetti, Maria Teresa M; Gomes, Ricristhi Gonçalves de A; Campos, Kauara B; Guedes, Raul Narciso C

    2016-01-01

    The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti) in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites. PMID:27143489

  4. Essential oils and their compounds as Aedes aegypti L. (Diptera: Culicidae) larvicides: review.

    Science.gov (United States)

    Dias, Clarice Noleto; Moraes, Denise Fernandes Coutinho

    2014-02-01

    This review aims to describe essential oils and their constituent compounds that exhibit bioactivity against Aedes aegypti L. (Diptera: Culicidae) larvae, the immature stage of the primary vector of dengue. This review is based on original articles obtained by searching on major databases. Our literature review revealed that 361 essential oils from 269 plant species have been tested for their larvicidal activity. More than 60 % of these essential oils were considered active (LC50temephos in container breeding. Approximately 27 % of the plants studied for their larvicidal activity against A. aegypti were collected in Brazil. Essential oils rich in phenylpropanoids, oxygenated sesquiterpenes, and monoterpene hydrocarbons were found to be the most active. When the isolates were tested, phenylpropanoids and monoterpene hydrocarbons were the most active compound classes. We describe the plant parts used and the major constituents of the essential oils. In addition, we discuss factors affecting the activity (such as plant parts, age of the plant, chemotypes, larval source, and methods used), structure-activity relationships, and mechanisms of action of the essential oils and their compounds. Essential oils have been widely investigated and show high larvicidal activity against A. aegypti. This review reveals that the essential oils are effective alternatives for the production of larvicides, which can be used in vector-borne disease control programmes. PMID:24265058

  5. Differential transcription profiles in Aedes aegypti detoxification genes after temephos selection.

    Science.gov (United States)

    Saavedra-Rodriguez, K; Strode, C; Flores, A E; Garcia-Luna, S; Reyes-Solis, G; Ranson, H; Hemingway, J; Black, W C

    2014-04-01

    The mosquito Aedes aegypti is the main vector of Dengue and Yellow Fever flaviviruses. The organophosphate insecticide temephos is a larvicide that is used globally to control Ae. aegypti populations; many of which have in turn evolved resistance. Target site alteration in the acetylcholine esterase of this species has not being identified. Instead, we tracked changes in transcription of metabolic detoxification genes using the Ae. aegypti 'Detox Chip' microarray during five generations of temephos selection. We selected for temephos resistance in three replicates in each of six collections, five from Mexico, and one from Peru. The response to selection was tracked in terms of lethal concentrations. Uniform upregulation was seen in the epsilon class glutathione-S-transferase (eGST) genes in strains from Mexico prior to laboratory selection, while eGSTs in the Iquitos Peru strain became upregulated after five generations of temephos selection. While expression of many carboxyl/cholinesterase esterase (CCE) genes increased with selection, no single esterase was consistently upregulated and this same pattern was noted in the cytochrome P450 monooxygenase (CYP) genes and in other genes involved in reduction or oxidation of xenobiotics. Bioassays using glutathione-S-transferase (GST), CCE and CYP inhibitors suggest that various CCEs instead of GSTs are the main metabolic mechanism conferring resistance to temephos. We show that temephos-selected strains show no cross resistance to permethrin and that genes associated with temephos selection are largely independent of those selected with permethrin in a previous study. PMID:24299217

  6. The use of Aedes aegypti larvae attractants to enhance the effectiveness of larvicides.

    Science.gov (United States)

    Gonzalez, Paula V; Harburguer, Laura; González-Audino, Paola A; Masuh, Héctor M

    2016-06-01

    Aedes aegypti (L.) is an important dengue, chikungunya, and yellow fever vector. Immature stages of this species inhabit human-made containers placed in residential landscapes, and the application of larvicides inside containers that cannot be eliminated is still considered a priority in control programs. Larvicidal efficacy is influenced by several factors, including the formulation used, the water quality, and the susceptibility of larvae, among others. If an attractant can be incorporated into a slow-release larvicide formulation, it will be feasible to direct the larvae into the source of insecticide and thereby improving its efficacy. We studied the influence of 1-octen-3ol and 3-methylphenol on the rate of Ae. aegypti larvae mortality using the larvicides Bacillus thuringiensis var. israelensis (Bti), temephos, and spinosad. These chemicals were combined with the larvicides mixed with agar during the bioassays. Mortality was registered every 10 min, and a lethal time 50 (LT50) was calculated. The inclusion of the Ae. aegypti larvae attractants with the larvicides into a solid agar matrix improved their efficiency obtaining a strong and marked reduction in the LT50 compared with the use of larvicides alone. PMID:26922177

  7. Silencing of P-glycoprotein increases mortality in temephos-treated Aedes aegypti larvae.

    Science.gov (United States)

    Figueira-Mansur, J; Ferreira-Pereira, A; Mansur, J F; Franco, T A; Alvarenga, E S L; Sorgine, M H F; Neves, B C; Melo, A C A; Leal, W S; Masuda, H; Moreira, M F

    2013-12-01

    Re-emergence of vector-borne diseases such as dengue and yellow fever, which are both transmitted by the Aedes aegypti mosquito, has been correlated with insecticide resistance. P-glycoproteins (P-gps) are ATP-dependent efflux pumps that are involved in the transport of substrates across membranes. Some of these proteins have been implicated in multidrug resistance (MDR). In this study, we identified a putative P-glycoprotein in the Ae. aegypti database based on its significantly high identity with Anopheles gambiae, Culex quinquefasciatus, Drosophila melanogaster and human P-gps. The basal ATPase activity of ATP-binding cassette transporters in larvae was significantly increased in the presence of MDR modulators (verapamil and quinidine). An eightfold increase in Ae. aegypti P-gp (AaegP-gp) gene expression was detected in temephos-treated larvae as determined by quantitative PCR. To analyse the potential role of AaegP-gp in insecticide efflux, a temephos larvicide assay was performed in the presence of verapamil. The results showed an increase of 24% in temephos toxicity, which is in agreement with the efflux reversing effect. RNA interference (RNAi)-mediated silencing of the AaegP-gp gene caused a significant increase in temephos toxicity (57%). In conclusion, we have demonstrated for the first time in insects that insecticide-induced P-gp expression can be involved in the modulation of insecticide efflux. PMID:23980723

  8. Intraspecific DNA variation in nuclear genes of the mosquito Aedes aegypti.

    Science.gov (United States)

    Morlais, I; Severson, D W

    2003-12-01

    Single nucleotide polymorphisms (SNPs) are an abundant source of genetic variation among individual organisms. To assess the usefulness of SNPs for genome analysis in the yellow fever mosquito, Aedes aegypti, we sequenced 25 nuclear genes in each of three strains and analysed nucleotide diversity. The average frequency of nucleotide variation was 12 SNPs per kilobase, indicating that nucleotide variation in Ae. aegypti is similar to that in other organisms, including Drosophila and the malaria vector Anopheles gambiae. Transition polymorphisms outnumbered transversion polymorphisms, at a ratio of about 2:1. We examined codon usage and confirmed that mutational bias favours G and C ending codons. Codon bias was most pronounced in highly expressed genes. Nucleotide diversity estimates indicated that substitution rates are positively correlated in coding and non-coding regions. Nucleotide diversity varied from one gene to another. The unequal distribution of SNPs among Ae. aegypti nuclear genes suggests that single base variations are non-neutral and are subject to selective constraints. Our analysis showed that ubiquitously expressed genes have lower polymorphism rates and are likely under strong purifying selection, whereas tissue specific genes and genes with a putative role in parasite defence exhibit higher levels of polymorphism that may be associated with diversifying selection. PMID:14986924

  9. The endosymbiotic bacterium Wolbachia induces resistance to dengue virus in Aedes aegypti.

    Science.gov (United States)

    Bian, Guowu; Xu, Yao; Lu, Peng; Xie, Yan; Xi, Zhiyong

    2010-04-01

    Genetic strategies that reduce or block pathogen transmission by mosquitoes have been proposed as a means of augmenting current control measures to reduce the growing burden of vector-borne diseases. The endosymbiotic bacterium Wolbachia has long been promoted as a potential vehicle for introducing disease-resistance genes into mosquitoes, thereby making them refractory to the human pathogens they transmit. Given the large overlap in tissue distribution and intracellular localization between Wolbachia and dengue virus in mosquitoes, we conducted experiments to characterize their interactions. Our results show that Wolbachia inhibits viral replication and dissemination in the main dengue vector, Aedes aegypti. Moreover, the virus transmission potential of Wolbachia-infected Ae. aegypti was significantly diminished when compared to wild-type mosquitoes that did not harbor Wolbachia. At 14 days post-infection, Wolbachia completely blocked dengue transmission in at least 37.5% of Ae. aegypti mosquitoes. We also observed that this Wolbachia-mediated viral interference was associated with an elevated basal immunity and increased longevity in the mosquitoes. These results underscore the potential usefulness of Wolbachia-based control strategies for population replacement. PMID:20368968

  10. Dispersal of Aedes aegypti: Field study in temperate areas using a novel method

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    Paula E. Bergero

    2013-08-01

    Full Text Available Background & objectives: Since Aedes aegypti was identified as vector of yellow fever and dengue, its dispersal is relevant for disease control. We studied the dispersal of Ae. aegypti in temperate areas of Argentina during egglaying, using the existing population and egg traps. Methods: Two independent replicas of a unique experimental design involving mosquitoes dispersing from an urbanized area to adjacent non-urbanized locations were carried out and analyzed in statistical terms. Results: We found relationship between stochastic variables related to the egg-laying mosquito activity (ELMA, useful to assess dispersal probabilities, despite the lack of knowledge of the total number of ovipositions in the zone. We propose to evaluate the egg-laying activity as minus the logarithm of the fraction of negative ovitraps at different distances from the buildings. Interpretation & conclusion: Three zones with different oviposition activity were determined, a corridor surrounding the urbanization, a second region between 10 and 25 m and the third region extending from 30 to 45 m from the urbanization. The landscape (plant cover and the human activity in the area appear to have an influence in the dispersal of Ae. aegypti. The proposed method worked consistently in two different replicas.

  11. Status Resistensi Aedes aegypti (Linn. terhadap Organofosfat di Tiga Kotamadya DKI Jakarta

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    Heni Prasetyowati

    2016-07-01

    Full Text Available High cases of Dengue Fever in Jakarta  increased efforts to control the population of Aedes aegypti by using insecticides. Insecticides which are often used in that control are malathion and temefos which derived from the class of organophospat. Associated with resistance in many areas, the purpose of this article is to know the susceptibility of Ae. aegypti in endemic areas in Jakarta to insecticide malathion and temefos. This study was an observational study with cross sectional design. Research sites in nine Puskesmas in East Jakarta, West Jakarta and South Jakarta. The study population was all the houses located in  highest endemic area  in nine regions of Puskesmas. Sample survey in the form of 100 homes / buildings in each area. Larvae survey conducted in the home / building, then the larvae obtained were collected for later colonization to  3rd generation. Susceptibility test to 0.8% malathion is done by using impregnated paper refers to the WHO method, whereas susceptibility test to temefos test was conducted by elliot.   Result of this research shows that  in all research areas have been resistant to organophosphate insecticides (Temefos and Malathion 0.8%. The use in the long term is suspected to be the cause of resistance to the insecticide malathion Ae.aegypti 0.8% and temefos 0,02ppm.  

  12. Mobility properties of the Hermes transposable element in transgenic lines of Aedes aegypti.

    Science.gov (United States)

    Smith, Ryan C; Atkinson, Peter W

    2011-01-01

    The Hermes transposable element has been used to genetically transform a wide range of insect species, including the mosquito, Aedes aegypti, a vector of several important human pathogens. Hermes integrations into the mosquito germline are characterized by the non-canonical integration of the transposon and flanking plasmid and, once integrated, Hermes is stable in the presence of its transposase. In an effort to improve the post-integration mobility of Hermes in the germline of Ae. aegypti, a transgenic helper Mos1 construct expressing Hermes transposase under the control of a testis-specific promoter was crossed to a separate transgenic strain containing a target Hermes transposon. In less than 1% of the approximately 1,500 progeny from jumpstarter lines analyzed, evidence of putative Hermes germline remobilizations were detected. These recovered transposition events occur through an aberrant mechanism and provide insight into the non-canonical cut-and-paste transposition of Hermes in the germ line of Ae. aegypti. PMID:20596755

  13. Identification and characterisation of Aedes aegypti aldehyde dehydrogenases involved in pyrethroid metabolism.

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    Nongkran Lumjuan

    Full Text Available Pyrethroid insecticides, especially permethrin and deltamethrin, have been used extensively worldwide for mosquito control. However, insecticide resistance can spread through a population very rapidly under strong selection pressure from insecticide use. The upregulation of aldehyde dehydrogenase (ALDH has been reported upon pyrethroid treatment. In Aedes aegypti, the increase in ALDH activity against the hydrolytic product of pyrethroid has been observed in DDT/permethrin-resistant strains. The objective of this study was to identify the role of individual ALDHs involved in pyrethroid metabolism.Three ALDHs were identified; two of these, ALDH9948 and ALDH14080, were upregulated in terms of both mRNA and protein levels in a DDT/pyrethroid-resistant strain of Ae. aegypti. Recombinant ALDH9948 and ALDH14080 exhibited oxidase activities to catalyse the oxidation of a permethrin intermediate, phenoxybenzyl aldehyde (PBald, to phenoxybenzoic acid (PBacid.ALDHs have been identified in association with permethrin resistance in Ae. aegypti. Characterisation of recombinant ALDHs confirmed the role of this protein in pyrethroid metabolism. Understanding the biochemical and molecular mechanisms of pyrethroid resistance provides information for improving vector control strategies.

  14. Differential transcription profiles in Aedes aegypti detoxification genes after temephos selection.

    Science.gov (United States)

    Saavedra-Rodriguez, K; Strode, C; Flores, A E; Garcia-Luna, S; Reyes-Solis, G; Ranson, H; Hemingway, J; Black, W C

    2014-04-01

    The mosquito Aedes aegypti is the main vector of Dengue and Yellow Fever flaviviruses. The organophosphate insecticide temephos is a larvicide that is used globally to control Ae. aegypti populations; many of which have in turn evolved resistance. Target site alteration in the acetylcholine esterase of this species has not being identified. Instead, we tracked changes in transcription of metabolic detoxification genes using the Ae. aegypti 'Detox Chip' microarray during five generations of temephos selection. We selected for temephos resistance in three replicates in each of six collections, five from Mexico, and one from Peru. The response to selection was tracked in terms of lethal concentrations. Uniform upregulation was seen in the epsilon class glutathione-S-transferase (eGST) genes in strains from Mexico prior to laboratory selection, while eGSTs in the Iquitos Peru strain became upregulated after five generations of temephos selection. While expression of many carboxyl/cholinesterase esterase (CCE) genes increased with selection, no single esterase was consistently upregulated and this same pattern was noted in the cytochrome P450 monooxygenase (CYP) genes and in other genes involved in reduction or oxidation of xenobiotics. Bioassays using glutathione-S-transferase (GST), CCE and CYP inhibitors suggest that various CCEs instead of GSTs are the main metabolic mechanism conferring resistance to temephos. We show that temephos-selected strains show no cross resistance to permethrin and that genes associated with temephos selection are largely independent of those selected with permethrin in a previous study.

  15. The endosymbiotic bacterium Wolbachia induces resistance to dengue virus in Aedes aegypti.

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    Guowu Bian

    2010-04-01

    Full Text Available Genetic strategies that reduce or block pathogen transmission by mosquitoes have been proposed as a means of augmenting current control measures to reduce the growing burden of vector-borne diseases. The endosymbiotic bacterium Wolbachia has long been promoted as a potential vehicle for introducing disease-resistance genes into mosquitoes, thereby making them refractory to the human pathogens they transmit. Given the large overlap in tissue distribution and intracellular localization between Wolbachia and dengue virus in mosquitoes, we conducted experiments to characterize their interactions. Our results show that Wolbachia inhibits viral replication and dissemination in the main dengue vector, Aedes aegypti. Moreover, the virus transmission potential of Wolbachia-infected Ae. aegypti was significantly diminished when compared to wild-type mosquitoes that did not harbor Wolbachia. At 14 days post-infection, Wolbachia completely blocked dengue transmission in at least 37.5% of Ae. aegypti mosquitoes. We also observed that this Wolbachia-mediated viral interference was associated with an elevated basal immunity and increased longevity in the mosquitoes. These results underscore the potential usefulness of Wolbachia-based control strategies for population replacement.

  16. Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro - Are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

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    Márcio Goulart Mocellin

    2009-12-01

    Full Text Available Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07% and five of Ae. albopictus(0.18% were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats.

  17. Spatial and Temporal Variation in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Numbers in the Yogyakarta Area of Java, Indonesia, With Implications for Wolbachia Releases.

    Science.gov (United States)

    Tantowijoyo, W; Arguni, E; Johnson, P; Budiwati, N; Nurhayati, P I; Fitriana, I; Wardana, S; Ardiansyah, H; Turley, A P; Ryan, P; O'Neill, S L; Hoffmann, A A

    2016-01-01

    of mosquito vector populations, particularly through Wolbachia endosymbionts. The success of these strategies depends on understanding the dynamics of vector populations. In preparation for Wolbachia releases around Yogyakarta, we have studied Aedes populations in five hamlets. Adult monitoring with BioGent- Sentinel (BG-S) traps indicated that hamlet populations had different dynamics across the year; while there was an increase in Aedes aegypti (L.) and Aedes albopictus (Skuse) numbers in the wet season, species abundance remained relatively stable in some hamlets but changed markedly (>2 fold) in others. Local rainfall a month prior to monitoring partly predicted numbers of Ae. aegypti but not Ae. albopictus. Site differences in population size indicated by BG-S traps were also evident in ovitrap data. Egg or larval collections with ovitraps repeated at the same location suggested spatial autocorrelation (<250 m) in the areas of the hamlets where Ae. aegypti numbers were high. Overall, there was a weak negative association (r<0.43) between Ae. aegypti and Ae. albopictus numbers in ovitraps when averaged across collections. Ae. albopictus numbers in ovitraps and BG-S traps were positively correlated with vegetation around areas where traps were placed, while Ae. aegypti were negatively correlated with this feature. These data inform intervention strategies by defining periods when mosquito densities are high, highlighting the importance of local site characteristics on populations, and suggesting relatively weak interactions between Ae. aegypti and Ae. albopictus. They also indicate local areas within hamlets where consistently high mosquito densities may influence Wolbachia invasions and other interventions.

  18. Investigating the Potential Range Expansion of the Vector Mosquito Aedes Aegypti in Mexico with NASA Earth Science Remote Sensing Results

    Science.gov (United States)

    Crosson, W. L.; Estes, M. G.; Estes, S. M.; Hayden, M.; Monaghan, A. J.; Eisen, L.; Lozano-Fuentes, S.; Ochoa, C.; Tapia, B.; Welsh-Rodriquez, C. M.; Quattrochi, D.; MorenoMadrinan, M. J.

    2012-01-01

    In tropical and sub ]tropical regions, the mosquito Aedes aegypti is the major vector for the virus causing dengue, a serious public health issue in these areas. Through ongoing NSF- and NASA-funded studies, field surveys of Aedes aegypti and an integrated modeling approach are being used to improve our understanding of the potential range of the mosquito to expand toward heavily populated high elevation areas such as Mexico City under various climate change and socio ]economic scenarios. This work serves three primary objectives: (1) Employ NASA remotely-sensed data to supplement the environmental monitoring and modeling component of the project. These data-- for example, surface temperature, precipitation, vegetation indices, soil moisture and elevation-- are critical for understanding the habitat necessary for mosquito survival and abundance; (2) Implement training sessions to instruct scientists and students from Mexico and the U.S. on how to use remote sensing and implement the NASA SERVIR Regional Visualization and Monitoring System; (3) Employ the SERVIR framework to optimize the dissemination of key project results in order to increase their societal relevance and benefits in developing climate adaptation strategies. Field surveys of larval, pupal and adult Aedes aegypti, as well as detailed physical and social household characteristics, were conducted in the summers of 2011and 2012 at geographic scales from the household to the community along a transect from sea level to 2400 m ASL. These data are being used in models to estimate Aedes aegypti habitat suitability. In 2011, Aedes aegypti were identified at an elevation of over 2150 m in Puebla, the highest elevation at which this species has been observed.

  19. Genome-based polymorphic microsatellite development and validation in the mosquito Aedes aegypti and application to population genetics in Haiti

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    Streit Thomas G

    2009-12-01

    Full Text Available Abstract Background Microsatellite markers have proven useful in genetic studies in many organisms, yet microsatellite-based studies of the dengue and yellow fever vector mosquito Aedes aegypti have been limited by the number of assayable and polymorphic loci available, despite multiple independent efforts to identify them. Here we present strategies for efficient identification and development of useful microsatellites with broad coverage across the Aedes aegypti genome, development of multiplex-ready PCR groups of microsatellite loci, and validation of their utility for population analysis with field collections from Haiti. Results From 79 putative microsatellite loci representing 31 motifs identified in 42 whole genome sequence supercontig assemblies in the Aedes aegypti genome, 33 microsatellites providing genome-wide coverage amplified as single copy sequences in four lab strains, with a range of 2-6 alleles per locus. The tri-nucleotide motifs represented the majority (51% of the polymorphic single copy loci, and none of these was located within a putative open reading frame. Seven groups of 4-5 microsatellite loci each were developed for multiplex-ready PCR. Four multiplex-ready groups were used to investigate population genetics of Aedes aegypti populations sampled in Haiti. Of the 23 loci represented in these groups, 20 were polymorphic with a range of 3-24 alleles per locus (mean = 8.75. Allelic polymorphic information content varied from 0.171 to 0.867 (mean = 0.545. Most loci met Hardy-Weinberg expectations across populations and pairwise FST comparisons identified significant genetic differentiation between some populations. No evidence for genetic isolation by distance was observed. Conclusion Despite limited success in previous reports, we demonstrate that the Aedes aegypti genome is well-populated with single copy, polymorphic microsatellite loci that can be uncovered using the strategy developed here for rapid and efficient

  20. Investigating the Potential Range Expansion of the Vector Mosquito Aedes aegypti in Mexico with NASA Earth Science Remote Sensing Results

    Science.gov (United States)

    Crosson, W. L.; Eisen, L.; Estes, M. G.; Estes, S. M.; Hayden, M.; Lozano-Fuentes, S.; Monaghan, A. J.; Moreno Madriñán, M. J.; Ochoa, C.; Quattrochi, D.; Tapia, B.; Welsh-Rodriguez, C. M.

    2012-12-01

    In tropical and sub-tropical regions, the mosquito Aedes aegypti is the major vector for the virus causing dengue, a serious public health issue in these areas. Through ongoing NSF- and NASA-funded studies, field surveys of Aedes aegypti and an integrated modeling approach are being used to improve our understanding of the potential range of the mosquito to expand toward heavily populated high elevation areas such as Mexico City under various climate change and socio-economic scenarios. This work serves three primary objectives: (1) Employ NASA remotely-sensed data to supplement the environmental monitoring and modeling component of the project. These data -- for example, surface temperature, precipitation, vegetation indices, soil moisture and elevation -- are critical for understanding the habitat necessary for mosquito survival and abundance; (2) Implement training sessions to instruct scientists and students from Mexico and the U.S. on how to use remote sensing and implement the NASA SERVIR Regional Visualization and Monitoring System; (3) Employ the SERVIR framework to optimize the dissemination of key project results in order to increase their societal relevance and benefits in developing climate adaptation strategies. Field surveys of larval, pupal and adult Aedes aegypti, as well as detailed physical and social household characteristics, were conducted in the summers of 2011and 2012 at geographic scales from the household to the community along a transect from sea level to 2400 m ASL. These data are being used in models to estimate Aedes aegypti habitat suitability. In 2011, Aedes aegypti were identified at an elevation of over 2150 m in Puebla, the highest elevation at which this species has been observed.

  1. Comparison of Aedes aegypti (Diptera: Culicidae) resting behavior on two fabric types under consideration for insecticide treatment in a push-pull strategy.

    Science.gov (United States)

    Tainchum, Krajana; Polsomboon, Suppaluck; Grieco, John P; Suwonkerd, Wannapa; Prabaripai, Atchariya; Sungvornyothin, Sungsit; Chareonviriyaphap, Theeraphap; Achee, Nicole L

    2013-01-01

    Aedes aegypti (L.), the primary vector of dengue and dengue hemorrhagic fever, breeds and rests predominately inside human dwellings. With no current vaccine available, vector control remains the mainstay for dengue management and novel approaches continue to be needed to reduce virus transmission. This requires a full understanding of Ae. aegypti ecology to design effective strategies. One novel approach is the use of contact irritants at target resting sites inside homes to make the surface unacceptable and cause vectors to escape before biting. The objective of the current study was to observe indoor resting behavior patterns of female Ae. aegypti within experimental huts in response to two fabrics under consideration for insecticide treatment: cotton and polyester. Results indicate that fabric type, coverage ratio of dark to light fabric and placement configuration (vertical vs. horizontal) all influenced the resting pattern of mosquito cohorts. Findings from this study will guide evaluations of a push-pull strategy designed to exploit contact irritant behaviors and drive Ae. aegypti out of homes prefeeding.

  2. Larvicidal activity against Aedes aegypti of Foeniculum vulgare essential oils from Portugal and Cape Verde.

    Science.gov (United States)

    Rocha, Diara Kady; Matosc, Olivia; Novoa, Maria Teresa; Figueiredo, Ana Cristina; Delgado, Manuel; Moiteiro, Cristina

    2015-04-01

    Dengue is a potentially fatal mosquito-borne infection with 50 million cases per year and 2.5 billion people vulnerable to the disease. This major public health problem has recurrent epidemics in Latin America and occurred recently in Cape Verde and Madeira Island. The lack of anti-viral treatment or vaccine makes the control of mosquito vectors a high option to prevent virus transmission. Essential oil (EO) constituents can affect insect's behaviour, being potentially effective in pest control. The present study evaluated the potential use of Foenicultm vulgare (fennel) EO in the control of the dengue vector Aedes aegypti. EOs isolated from fennel aerial parts collected in Cape Verde and from a commercial fennel EO of Portugal were analysed by NMR, GC and GC-MS. trans-Anethole (32 and 30%, respectively), limonene (28 and 18%, respectively) and fenchone (10% in both cases) were the main compounds identified in the EOs isolated from fennel from Cape Verde and Portugal, respectively. The larvicidal activity of the EOs and its major constituents were evaluated, using WHO procedures, against third instar larvae ofAe. aegypti for 24 h. Pure compounds, such as limonene isomers, were also assayed. The lethal concentrations LC50, C90 and LC99 were determined by probit analysis using mortality rates of bioassays. A 99% mortality of Ae. aegypti larvae was estimated at 37.1 and 52.4 µL L-1 of fennel EOs from Cape Verde and Portugal, respectively. Bioassays showed that fennel EOs from both countries displayed strong larvicidal effect against Ae. aegypti, the Cape Verde EO being as active as one of its major constituents, (-)-limonene. PMID:25973508

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

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    Leon E Hugo

    2014-02-01

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

  4. Suppression of RNA interference increases alphavirus replication and virus-associated mortality in Aedes aegypti mosquitoes

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    Geiss Brian J

    2009-03-01

    Full Text Available Abstract Background Arthropod-borne viruses (arboviruses can persistently infect and cause limited damage to mosquito vectors. RNA interference (RNAi is a mosquito antiviral response important in restricting RNA virus replication and has been shown to be active against some arboviruses. The goal of this study was to use a recombinant Sindbis virus (SINV; family Togaviridae; genus Alphavirus that expresses B2 protein of Flock House virus (FHV; family Nodaviridae; genus Alphanodavirus, a protein that inhibits RNAi, to determine the effects of linking arbovirus infection with RNAi inhibition. Results B2 protein expression from SINV (TE/3'2J inhibited the accumulation of non-specific small RNAs in Aedes aegypti mosquito cell culture and virus-specific small RNAs both in infected cell culture and Ae. aegypti mosquitoes. More viral genomic and subgenomic RNA accumulated in cells and mosquitoes infected with TE/3'2J virus expressing B2 (TE/3'2J/B2 compared to TE/3'2J and TE/3'2J virus expressing GFP. TE/3'2J/B2 exhibited increased infection rates, dissemination rates, and infectious virus titers in mosquitoes following oral bloodmeal. Following infectious oral bloodmeal, significantly more mosquitoes died when TE/3'2J/B2 was ingested. The virus was 100% lethal following intrathoracic inoculation of multiple mosquito species and lethality was dose-dependent in Ae. aegypti. Conclusion We show that RNAi is active in Ae. aegypti cell culture and that B2 protein inhibits RNAi in mosquito cells when expressed by a recombinant SINV. Also, SINV more efficiently replicates in mosquito cells when RNAi is inhibited. Finally, TE/3'2J/B2 kills mosquitoes in a dose-dependent manner independent of infection route and mosquito species.

  5. Larvicidal activity of Annona senegalensis and Boswellia dalzielii leaf fractions against Aedes aegypti (Diptera: Culicidae

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    Younoussa Lame

    2014-12-01

    Full Text Available The purpose of the present study was to evaluate the larvicidal activity of leaf fractions of Annona senegalensis and Boswellia dalzielii against fourth instar larvae of Aedes aegypti. Fourth instar larvae of Ae. aegypti were exposed for 24 hours to various concentrations (312.5-2500 mg/L of methanolic crude extract and its fractions obtained with n-hexane, chloroform, ethyl-acetate and methanol solvents, following WHO method. The mortalities recorded were subjected to ANOVA test for mean comparison and Probit analysis to determine LC50. Preliminary phytochemical screening test for some components of the plants assessed were also evaluated. The phytochemical screening of the two plants revealed the presence of alkaloids, steroids, phenolic compounds, terpenoids, fats and oils in the crude extracts which, after splitting were most distributed in n-hexane and chloroform fractions. Apart from methanol fraction, all products used showed a significant (P<0.001 concentration-dependent toxicity against Ae. aegypti larvae. The LC50 recorded with crude extract were 759.6 and 830.4 mg/L for A. senegalensis and B. dalzielli respectively. After fractionation, n-hexane and chloroform fractions of A. senegalensis revealed more effective activity than others with CL50 values of 379.3 and 595.2 mg/L respectively. As for B. dalzielli, n-hexane (LC50=537.1 mg/L and chloroform (LC50=585.5 mg/L fractions were also the most effective. These results suggest that the n-hexane and chloroform fractions of these plants as a promising larvicide against Ae. aegypti and can constitute the best basic and vital step in the development of a botanical insecticide source.

  6. Bioefficacy of Mentha piperita essential oil against dengue fever mosquito Aedes aegypti L

    Science.gov (United States)

    Kumar, Sarita; Wahab, Naim; Warikoo, Radhika

    2011-01-01

    Objective To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant, Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti). Methods The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae of Ae. aegypti using WHO protocol. The mortality counts were made after 24 and 48 h, and LC50 and LC90 values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for 3 min after every 15 min. The experiment continued for 3 h and the percent protection was calculated. Results The essential oil extracted from M. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC50 and LC90 value of 111.9 and 295.18 ppm, respectively after 24 h of exposure. The toxicity of the oil increased 11.8% when the larvae were exposed to the oil for 48 h. The remarkable repellent properties of M. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in 100% protection till 150 min. After next 30 min, only 1-2 bites were recorded as compared with 8-9 bites on the control arm. Conclusions The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control. PMID:23569733

  7. Insecticide resistance in two Aedes aegypti (Diptera: Culicidae) strains from Costa Rica.

    Science.gov (United States)

    Bisset, J A; Marín, R; Rodríguez, M M; Severson, D W; Ricardo, Y; French, L; Díaz, M; Pérez, O

    2013-03-01

    Dengue (family Flaviridae, genus Flavivirus, DENV) and dengue hemorrhagic fever (DHF) are presently important public health problems in Costa Rica. The primary strategy for disease control is based on reducing population densities of the main mosquito vector Aedes aegypti (L.) (Diptera: Culicidae). This is heavily dependent on use of chemical insecticides, thus the development of resistance is a frequent threat to control program effectiveness. The objective of this study was to determine the levels of insecticide resistance and the metabolic resistance mechanisms involved in two Ae. aegypti strains collected from two provinces (Puntarenas and Limon) in Costa Rica. Bioassays with larvae were performed according to World Health Organization guidelines and resistance in adults was measured through standard bottle assays. The activities of beta-esterases, cytochrome P450 monooxygenases, and glutathione S-transferases (GST), were assayed through synergists and biochemical tests, wherein the threshold criteria for each enzyme was established using the susceptible Rockefeller strain. The results showed higher resistance levels to the organophosphate (OP) temephos and the pyrethroid deltamethrin in larvae. The efficacy of commercial formulations of temephos in controlling Ae. aegypti populations was 100% mortality up to 11 and 12 d posttreatment with daily water replacements in test containers. Temephos and deltamethrin resistance in larvae were associated with high esterase activity, but not to cytochrome P450 monooxygenase or GST activities. Adult mosquitoes were resistant to deltamethrin, and susceptible to bendiocarb, chlorpyrifos, and cypermethrin. Because temephos and deltamethrin resistance are emerging at the studied sites, alternative insecticides should be considered. The insecticides chlorpyrifos and cypermethrin could be good candidates to use as alternatives for Ae. aegypti control. PMID:23540124

  8. Application of wMelPop Wolbachia Strain to Crash Local Populations of Aedes aegypti.

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    Scott A Ritchie

    Full Text Available The endosymbiotic bacteria Wolbachia pipientis (wMel strain has been successfully established in several populations of Aedes aegypti, the primary dengue vector. The virulent Wolbachia strain wMelPop is known to cause several pathological impacts (increased egg mortality, life shortening, etc. reducing overall fitness in the mosquito Ae. aegypti. Increased egg mortality could substantially reduce egg banks in areas with a lengthy monsoonal dry season, and be employed to eliminate local populations. We tested this application under semi-field cage conditions. First, we determined that wMelPop infection significantly reduced the survival of desiccation-resistant eggs of the dengue vector Ae. aegypti, with shade and temperature having a significant impact; nearly all wMelPop-infected eggs failed to hatch after 6 and 10 weeks in summer and winter conditions, respectively. In laboratory selection experiments we found that egg desiccation resistance can be increased by selection, and that this effect of wMelPop infection is due to the nuclear background of the host rather than Wolbachia. We then conducted an invasion of wMelPop within a semi-field cage using sustained weekly releases of wMelPop infected mosquitoes, with fixation achieved after 9 weeks. The egg populations wMelPop infected and an uninfected control were then subjected to a simulated prolonged monsoonal dry season (2.5 months before flooding to induce hatching. The wMelPop infected eggs suffered significantly greater mortality than the controls, with only 0.67% and 4.35% of respective infected and uninfected eggs held in 99% shade hatching after 80 days. These studies suggest that wMelPop could be used to locally eliminate populations of Ae. aegypti that are exposed to prolonged dry conditions, particularly if combined with vector control.

  9. Redeployment of a conserved gene regulatory network during Aedes aegypti development.

    Science.gov (United States)

    Suryamohan, Kushal; Hanson, Casey; Andrews, Emily; Sinha, Saurabh; Scheel, Molly Duman; Halfon, Marc S

    2016-08-15

    Changes in gene regulatory networks (GRNs) underlie the evolution of morphological novelty and developmental system drift. The fruitfly Drosophila melanogaster and the dengue and Zika vector mosquito Aedes aegypti have substantially similar nervous system morphology. Nevertheless, they show significant divergence in a set of genes co-expressed in the midline of the Drosophila central nervous system, including the master regulator single minded and downstream genes including short gastrulation, Star, and NetrinA. In contrast to Drosophila, we find that midline expression of these genes is either absent or severely diminished in A. aegypti. Instead, they are co-expressed in the lateral nervous system. This suggests that in A. aegypti this "midline GRN" has been redeployed to a new location while lost from its previous site of activity. In order to characterize the relevant GRNs, we employed the SCRMshaw method we previously developed to identify transcriptional cis-regulatory modules in both species. Analysis of these regulatory sequences in transgenic Drosophila suggests that the altered gene expression observed in A. aegypti is the result of trans-dependent redeployment of the GRN, potentially stemming from cis-mediated changes in the expression of sim and other as-yet unidentified regulators. Our results illustrate a novel "repeal, replace, and redeploy" mode of evolution in which a conserved GRN acquires a different function at a new site while its original function is co-opted by a different GRN. This represents a striking example of developmental system drift in which the dramatic shift in gene expression does not result in gross morphological changes, but in more subtle differences in development and function of the late embryonic nervous system.

  10. Bioefficacy ofMentha piperita essential oil against dengue fever mosquito Aedes aegypti L

    Institute of Scientific and Technical Information of China (English)

    Sarita Kumar; Naim Wahab; Radhika Warikoo

    2011-01-01

    Objective:To assess the larvicidal and repellent potential of the essential oil extracted from the leaves of peppermint plant,Mentha piperita (M. piperita) against the larval and adult stages of Aedes aegypti (Ae. Aegypti).Methods: The larvicidal potential of peppermint oil was evaluated against early fourth instar larvae ofAe. aegypti usingWHO protocol. The mortality counts were made after 24 and48 h, and LC50 and LC90values were calculated. The efficacy of peppermint oil as mosquito repellent was assessed using the human-bait technique. The measured area of one arm of a human volunteer was applied with the oil and the other arm was applied with ethanol. The mosquito bites on both the arms were recorded for3 min after every15 min. The experiment continued for 3 h and the percent protection was calculated.Results:The essential oil extracted fromM. piperita possessed excellent larvicidal efficiency against dengue vector. The bioassays showed an LC50 and LC90 value of111.9 and295.18 ppm, respectively after24 h of exposure. The toxicity of the oil increased11.8% when the larvae were exposed to the oil for48 h. The remarkable repellent properties ofM. piperita essential oil were established against adults Ae. aegypti. The application of oil resulted in100% protection till150 min. After next30min, only1-2 bites were recorded as compared with8-9 bites on the control arm.Conclusions:The peppermint essential oil is proved to be efficient larvicide and repellent against dengue vector. Further studies are needed to identify the possible role of oil as adulticide, oviposition deterrent and ovicidal agent. The isolation of active ingredient from the oil could help in formulating strategies for mosquito control.

  11. [Detection of Aedes aegypti and Aedes albopictus, in an urban zone of the municipality of Catanduva, SP, after control of a Dengue epidemic].

    Science.gov (United States)

    Cardoso Júnior, R P; Scandar, S A; de Mello, N V; Ernandes, S; Botti, M V; Nascimento, E M

    1997-01-01

    After the realization of control research that had in view the transmission of dengue virus, we started to monitor two kinds of entomological vigilance, Breteau Index and ovitrap. We intended to evaluate the necessary time elapsed before Aedes sp mosquitoes were again detected at the urban area of Catanduva s town (SP). The ovitraps showed positiveness for the Aedes aegypti two months after the control research, while the Breteau Index became positive only at the fourth month after the end of the referred research.

  12. Mosquito larvicidal effect of orthophosporic acid and lactic acid individually or their combined form on Aedes aegypti

    Institute of Scientific and Technical Information of China (English)

    Supratik Chakraborty; Someshwar Singha; Goutam Chandra

    2010-01-01

    Objective: To observe the effect of two common organic acids on the larvae of Aedes aegypti (Ae. aegypti) (L), the natural vector of dengue fever/dengue hemorrhage fever, chikugunya and allergic skin reaction especially in children. Methods: Two common organic acids (lactic acid and orthophosporic acid of gradually increasing concentration) were used against laboratory reared third instars larvae of Ae. aegypti in order to observe the rate of mortality after 8, 16 and 24 h of post exposure respectively in laboratory. Results: Larval mortality rates recorded were in the following sequences: orthophosphoric acid and lactic acid at 1:1 combination >orthophosphoric acid>lactic acid. Conclusions: These two organic acids may be used perfectly in combination (1:1) along with other conventional vector control methods to reduce the Ae. aegypti population, especially in those areas where surveillance and supervisory mechanism are poor or insufficient.

  13. Field efficacy of new larvicide products for control of multi-resistant Aedes aegypti populations in Martinique (French West Indies).

    Science.gov (United States)

    Marcombe, Sébastien; Darriet, Frédéric; Agnew, Philip; Etienne, Manuel; Yp-Tcha, Marie-Michelle; Yébakima, André; Corbel, Vincent

    2011-01-01

    World-wide dengue vector control is hampered by the spread of insecticide resistance in Aedes aegypti. We report the resistance status of a wild Ae. aegypti population from Martinique (Vauclin) to conventional larvicides (Bacillus thuringiensis var israeliensis [Bti] and temephos) and potential alternatives (spinosad, diflubenzuron, and pyriproxyfen). The efficacy and residual activity of these insecticides were evaluated under simulated and field conditions. The Vauclin strain exhibited a high level of resistance to temephos, a tolerance to insect growth regulators, and full susceptibility to spinosad and Bti. In simulated trials, pyriproxyfen and Bti showed long residual activities in permanent breeding containers (28 and 37 weeks), whereas under field conditions they failed to curtail Ae. aegypti populations after four weeks. Conversely, diflubenzuron and spinosad showed a residual efficacy of 16 weeks, suggesting that these chemicals may be promising alternatives to Bti and temephos for controlling insecticide-resistant Ae. aegypti populations.

  14. Mosquito adulticidal properties of Delonix elata (Family:Fabaceae) against dengue vector, Aedes aegypti (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Mohan Rajeswary; Marimuthu Govindarajan

    2014-01-01

    Objective:To determine the adulticidal activity of hexane, benzene, chloroform, ethyl acetate and methanol leaf and seed extracts of Delonix elata (D. elata) against Aedes aegypti (Ae. aegypti). Methods:The bioassay was conducted in an experimental kit consisting of two cylindrical plastic tubes both measuring 125 mm×44 mm following the WHO method;mortality of the mosquitoes was recorded after 24 h. Results: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 D. elata against Ae. aegypti with the LC50 and LC90 values 162.87 and 309.32 mg/L, respectively. Conclusions:From this result, it can be concluded the crude extract of D. elata was an excellent potential for controlling Ae. aegypti mosquitoes.

  15. Toxicity studies for indigenous Bacillus thuringiensis isolates from Malang city, East Java on Aedes aegypti larvae

    Institute of Scientific and Technical Information of China (English)

    Zulfaidah Penata Gama; Nobukazu Nakagoshi; Suharjono; Faridah Setyowati

    2013-01-01

    Objective: To investigate the toxicity of indigenous Bacillus thuringiensis (B. thuringiensis) isolates from Malang City for controlling Aedes aegypti (Ae. aegypti) larvae. Methods: Soil samples were taken from Purwantoro and Sawojajar sub-districts. Bacterial isolation was performed using B. thuringiensis selective media. Phenotypic characteristics of the isolates were obtained with the simple matching method. The growth and prevalence of spores were determined by the Total Plate Count method, and toxicity tests were also performed on the third instar larval stage of Ae. aegypti. The percentage of larval mortality was analysed using probit regression. The LC50 was analysed by ANOVA, and the Tukey HSD interval was 95%. Results:Among the 33 selected bacterial isolates, six were obtained (PWR4-31, PWR4-32, SWJ4-2b, SWJ4-4b, SWJ-4k and SWJ5-1) that had a similar phenotype to reference B. thuringiensis. Based on the dendrogram, all of the bacterial isolates were 71%similar. Three isolates that had a higher prevalence of reference B. thuringiensis were PWR4-32, SWJ4-4b and SW5-1, of which the spore prevalence was 52.44%, 23.59%, 34.46%, respectively. These three indigenous isolates from Malang City successfully killed Ae. aegypti larvae. The PWR4-32 isolates were the most effective at killing the larvae. Conclusions:Six indigenous B. thuringiensis isolates among the 33 bacterial isolates found in the Sawojajar and Purwantoro sub-districts were toxic to the third instar larvae of Ae. aegypti. The PWR4-32 isolates were identical to the reference B. thuringiensis and had 88%phenotype similarity. The PWR4-32 isolates had the highest spore prevalence (52.44%), and the early stationary phase occurred at 36 h. The PWR4-32 isolates were the most effective at killing Ae. aegypti larvae (LC50-72 h=2.3í108 cells/mL).

  16. The consequences of co-infections for parasite transmission in the mosquito Aedes aegypti.

    Science.gov (United States)

    Duncan, Alison B; Agnew, Philip; Noel, Valérie; Michalakis, Yannis

    2015-03-01

    Co-infections may modify parasite transmission opportunities directly as a consequence of interactions in the within-host environment, but also indirectly through changes in host life history. Furthermore, host and parasite traits are sensitive to the abiotic environment with variable consequences for parasite transmission in co-infections. We investigate how co-infection of the mosquito Aedes aegypti with two microsporidian parasites (Vavraia culicis and Edhazardia aedis) at two levels of larval food availability affects parasite transmission directly, and indirectly through effects on host traits. In a laboratory infection experiment, we compared how co-infection, at low and high larval food availability, affected the probability of infection, within-host growth and the transmission potential of each parasite, compared to single infections. Horizontal transmission was deemed possible for both parasites when infected hosts died harbouring horizontally transmitting spores. Vertical transmission was judged possible for E. aedis when infected females emerged as adults. We also compared the total input number of spores used to seed infections with output number, in single and co-infections for each parasite. The effects of co-infection on parasite fitness were complex, especially for V. culicis. In low larval food conditions, co-infection increased the chances of mosquitoes dying as larvae or pupae, thus increasing opportunities for V. culicis' horizontal transmission. However, co-infection reduced larval longevity and hence time available for V. culicis spore production. Overall, there was a negative net effect of co-infection on V. culicis, whereby the number of spores produced was less than the number used to seed infection. Co-infections also negatively affected horizontal transmission of the more virulent parasite, E. aedis, through reduced longevity of pre-adult hosts. However, its potential transmission suffered less relative to V. culicis. Our results