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Sample records for aedes triseriatus mosquitoes

  1. Laboratory evaluation of mosquito repellents against Aedes albopictus, Culex nigripalpus, and Ochierotatus triseriatus (Diptera: Culicidae).

    Science.gov (United States)

    Barnard, Donald R; Xue, Rui-De

    2004-07-01

    Four synthetic mosquito repellents (Autan [10% KBR3023], IR3535 [7.5%], Off! [15% deet], Skinsations [7% deet]) and eight natural (primarily plant extracts and/or essential oils) product-based repellents (Bite Blocker [2% soybean oil], ByGone, GonE!, Natrapel [10% citronella], Neem Aura, Sunswat, MosquitoSafe [25% geraniol], and Repel [26% p-menthane-3,8-diol]) were tested in the laboratory against Aedes albopictus Skuse, Culex nigripalpus Theobald, and Ochlerotatus triseriatus (Say). When estimated mean protection time (eMPT) responses for each repellent were averaged for all three mosquito species, Autan, Bite Blocker, Off!, and Repel prevented biting for > or =7.2 h; IR3535, MosquitoSafe, and Skinsations for 3.2-4.8 h; and ByGone, Natrapel, GonE, NeemAura, and SunSwat for 0.9-2.3 h. Against Ae. albopictus, the eMPT for Off! and Repel exceeded 7.0 h and ranged from 5.0 to 5.7 h for Autan, Bite Blocker, and Skinsations. Bygone, GonE, NeemAura, and SunSwat provided 0.2 h protection against Ae. albopictus and Oc. triseriatus, whereas Autan, Bite Blocker, Off., and Repel prevented bites by Oc. triseriatus for > or =7.3 h. All 12 repellents provided an eMPT > or =2.8 h against Cx. nigripalpus (maximum: 8.5 h for Bite Blocker). When the average eMPT for each repellent (for all species) was divided by the eMPT for 7% deet (Skinsations), the order of repellent effectiveness and the corresponding repellency index (R,) was Repel (1.7) > Bite Blocker (1.5) = Autan (1.5) = Off! (1.5) > Skinsations (1.0) > IR3535 (0.8) > MosquitoSafe (0.6) > Natrapel (0.5) > Neem Aura (0.3) = SunSwat (0.3) = Bygone (0.3) > GonE (0.2). PMID:15311467

  2. Effects of Larval Mosquitoes (Aedes triseriatus) and Stemflow on Microbial Community Dynamics in Container Habitats†

    OpenAIRE

    Kaufman, Michael G.; Walker, Edward D; Smith, Tracy W.; Merritt, Richard W.; Klug, Michael J.

    1999-01-01

    The dynamics of the microbial food sources for Aedes triseriatus larvae in microcosms were found to be strongly influenced by larval presence. The total abundance of bacteria in water samples generally increased in response to larvae, including populations of cultivable, facultatively anaerobic bacteria. Additionally, a portion of the community shifted from Pseudomonaceae to Enterobacteriaceae. Bacterial abundance on leaf material was significantly reduced in the presence of actively feeding ...

  3. Prior Hydrologic Disturbance Affects Competition between Aedes Mosquitoes via Changes in Leaf Litter.

    Science.gov (United States)

    Smith, Cassandra D; Freed, T Zachary; Leisnham, Paul T

    2015-01-01

    Allochthonous leaf litter is often the main resource base for invertebrate communities in ephemeral water-filled containers, and detritus quality can be affected by hydrologic conditions. The invasive mosquito Aedes albopictus utilizes container habitats for its development where it competes as larvae for detritus and associated microorganisms with the native Aedes triseriatus. Different hydrologic conditions that containers are exposed to prior to mosquito utilization affect litter decay and associated water quality. We tested the hypothesis that larval competition between A. albopictus and A. triseriatus would be differentially affected by prior hydrologic conditions. Experimental microcosms provisioned with Quercus alba L. litter were subjected to one of three different hydrologic treatments prior to the addition of water and mosquito larvae: dry, flooded, and a wet/dry cycle. Interspecific competition between A. albopictus and A. triseriatus was mediated by hydrologic treatment, and was strongest in the dry treatment vs. the flooded or wet/dry treatments. Aedes triseriatus estimated rate of population change (λ') was lowest in the dry treatment. Aedes albopictus λ' was unaffected by hydrologic treatment, and was on average always increasing (i.e., > 1). Aedes triseriatus λ' was affected by the interaction of hydrologic treatment with interspecific competition, and was on average declining (i.e., Changing rainfall patterns with climate change are likely to affect competition between A. triseriatus and A. albopictus, probably enhancing negative competitive effects of A. albopictus on A. triseriatus in areas that experience drought. PMID:26035819

  4. Midgut fungal and bacterial microbiota of Aedes triseriatus and Aedes japonicus shift in response to La Crosse virus infection.

    Science.gov (United States)

    Muturi, Ephantus J; Bara, Jeffrey J; Rooney, Alejandro P; Hansen, Allison K

    2016-08-01

    Understanding how midgut microbial communities of field-collected mosquitoes interact with pathogens is critical for controlling vector infection and disease. We used 16S rRNA and internal transcribed spacer sequencing to characterize the midgut bacterial and fungal communities of adult females of Aedes triseriatus and Aedes japonicus collected as pupae in tree holes, plastic bins and waste tires and their response to La Crosse virus (LACV) infection. For both mosquito species and across all habitat and virus treatments, a total of 62 bacterial operational taxonomic units (OTUs) from six phyla and 21 fungal OTUs from two phyla were identified. The majority of bacterial (92%) and fungal (71%) OTUs were shared between the mosquito species; however, several OTUs were unique to each species. Bacterial and fungal communities of individuals that took either infectious or noninfectious bloodmeals were less diverse and more homogeneous compared to those of newly emerged adults. Interestingly, LACV-infected A. triseriatus and A. japonicus had higher bacterial richness and lower fungal richness compared to individuals that took a noninfectious bloodmeal, suggesting that viral infection was associated with an increase in bacterial OTUs and a decrease in fungal OTUs. For both mosquito species, several OTUs were identified that had both high fidelity and specificity to mosquito midguts that were infected with LACV. Overall, these findings demonstrate that bacterial and fungal communities that reside in mosquito midguts respond to host diet and viral infection and could play a role in modulating vector susceptibility to LACV. PMID:27357374

  5. Residual toxicity of four insecticides to Aedes triseriatus in scrap tires.

    Science.gov (United States)

    Beehler, J W; Quick, T C; DeFoliart, G R

    1991-03-01

    Four insecticides were tested for residual activity to Aedes triseriatus in scrap tires. Abate (temephos) granules applied at 10 ppm (AI) resulted in 100% mortality of 4th instar larvae for more than one year. The other insecticides caused no mortality within 4 wk after application. PMID:2045803

  6. Successional mosquito dynamics in surrogate treehole and ground-container habitats in the northeastern United States: where does Aedes albopictus fit in?

    Science.gov (United States)

    Johnson, B J; Sukhdeo, M V K

    2013-06-01

    This study assessed the risk of larval displacement of the eastern treehole mosquito, Aedes triseriatus, and the northern house mosquito, Culex pipiens, by Aedes albopictus, the Asian tiger mosquito, during the establishment and successional stages of novel larval mosquito treehole and ground-container habitats in the state of New Jersey, U.S.A. Culex pipiens and Culex restuans were the first mosquito species to colonize ground-container habitats and were the dominant larval species throughout the study period, whereas Ae. albopictus was late to colonize ground habitats and accounted for less than 15% of weekly larval collections once established. Ae. albopictus had a much stronger community presence within treehole ovitraps; however, Ae. albopictus never reached the average larval densities of the expected primary colonizer, Ae. triseriatus. Throughout the study period, the weekly abundances of Ae. triseriatus and Ae. albopictus were positively correlated and there were no significant differences between the abundances of each species. The larval dominance of Ae. triseriatus appears to be enhanced by the presence of Toxorhynchites rutilus septentrionalis, a large predatory mosquito species. When Tx. rut. septentrionalis was present, mature larvae (3(rd) -4(th) instar) of Ae. albopictus were also present in only 16.7% of collections, whereas mature larvae of Ae. triseriatus were collected concurrently with Tx. rut. septentrionalis in 53.8% of collections. These data suggest that Ae. triseriatus is at a greater risk of displacement by Ae. albopictus than are Cx. pipiens and Cx. restuans. PMID:23701622

  7. Leaf-Associated Bacterial and Fungal Taxa Shifts in Response to Larvae of the Tree Hole Mosquito, Ochlerotatus triseriatus

    OpenAIRE

    Kaufman, Michael G.; Chen, Shicheng; Walker, Edward D

    2008-01-01

    Larvae of the eastern tree hole mosquito, Ochlerotatus triseriatus (Say), and related container-breeding species are known to feed upon substrate-associated microorganisms. Although the importance of these microbial resources to larval growth has been established, almost nothing is known about the taxonomic composition and dynamics of these critical microbial food sources. We examined bacterial and fungal community compositional changes on oak leaves tethered in natural tree hole habitats of ...

  8. Promising new tools to fight Aedes mosquitoes.

    Science.gov (United States)

    2016-08-01

    Two new tools for suppressing Aedes aegypti mosquito populations have been recommended for pilot testing. Carefully designed trials will be needed to see whether they actually reduce disease as well. Andréia Azevedo Soares reports. PMID:27516632

  9. 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...

  10. 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 ...

  11. History of Aedes mosquitoes in Hawaii.

    Science.gov (United States)

    Winchester, Jonathan C; Kapan, Durrell D

    2013-06-01

    As a geographically isolated island chain with no native mosquitoes, Hawaii is a model for examining the mechanisms behind insect vector invasions and their subsequent interactions with each other and with human populations. The yellow fever mosquito, Aedes aegypti, and the Asian tiger mosquito, Ae. albopictus, have been responsible for epidemics of dengue in Hawaii. As one of the world's earliest locations to be invaded by both species, Hawaii's history is particularly relevant because both species are currently invading new areas worldwide and are implicated in outbreaks of emergent or reemergent pathogens such as dengue, chikungunya, and yellow fever. Here we analyze the historical records of mosquito introductions in order to understand the factors that have led to the current distribution of these 2 mosquitoes in the Hawaiian Islands. PMID:23923330

  12. 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...

  13. Comparison of Mosquito Magnet and Biogents Sentinel Traps for Operational Surveillance of Container-Inhabiting Aedes (Diptera: Culicidae) Species.

    Science.gov (United States)

    Rochlin, Ilia; Kawalkowski, Margaret; Ninivaggi, Dominick V

    2016-03-01

    Container-inhabiting Aedes are among the most medically important mosquito vectors of diseases. They also impact health and quality of life by their persistent and severe biting. Monitoring of container-inhabiting Aedes species is challenging due to the need for specialized traps and lures. Biogents Sentinel (BGS) trap has become a standard for Aedes albopictus (Skuse) surveillance; however, it has substantial problems with durability, quality of construction, and sample exposure to the elements. The goal of this study was to develop a methodology for collecting medically important container-inhabiting Aedes species in numbers sufficient for population trend analysis, control efficacy studies, and pathogen testing. Mosquito Magnets (MM) baited with BG lure and R-octenol were selected as the most practical alternative to BGS, collecting significantly more Ae. albopictus (32.1 ± 0.7 vs. 5.6 ± 0.1), Aedes japonicus (Theobald) (10.1 ± 0.4 vs. 1.2 ± 0.02), and Aedes triseriatus (Say) (0.9 ± 0.04 vs. 0.04 ± 0.004) females on average per trapping under a variety of weather conditions. MM can be particularly useful for long-term surveillance or when large numbers of specimens are required for pathogen isolation, such as at the sites with suspected dengue or chikungunya transmission. PMID:26520482

  14. Dispersal of Engineered Male Aedes aegypti Mosquitoes.

    Directory of Open Access Journals (Sweden)

    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.

  15. Male reproductive biology of Aedes mosquitoes.

    Science.gov (United States)

    Oliva, Clelia F; Damiens, David; Benedict, Mark Q

    2014-04-01

    Among Aedes mosquitoes are species responsible for transmission of serious pathogens to humans. To cope with the current threats to long-term effectiveness of the traditional vector control methods, non-conventional control strategies are being developed. These include autocidal control such as the release of sterile males (sterile insect technique) and the release of Wolbachia-infected males to induce sexual sterility (incompatible insect technique) and pathogen-refractory strain replacement variations using Wolbachia. Sterile male types of techniques particularly depend on released males' ability to successfully mate with wild females. For that reason, a good understanding of male mating biology, including a thorough understanding of the reproductive system and mating capacity, increases the likelihood of success of such genetic vector control programmes. Here we review the literature concerning the reproduction of Aedes mosquitoes with an emphasis on the male biology. We consider sexual maturation, mate finding, insemination, male reproductive capacity, and the occurrence of multiple matings. We also discuss which parameters are of greatest importance for the successful implementation of autocidal control methods and propose questions for future research. PMID:24308996

  16. Dirofilaria repens microfilariae in Aedes vexans mosquitoes in Slovakia

    Czech Academy of Sciences Publication Activity Database

    Bocková, E.; Rudolf, Ivo; Kočišová, A.; Betášová, Lenka; Venclíková, Kristýna; Mendel, Jan; Hubálek, Zdeněk

    2013-01-01

    Roč. 112, č. 10 (2013), s. 3465-3470. ISSN 0932-0113 Institutional support: RVO:68081766 Keywords : Dirofilaria * mosquitoes * Aedes vexans Subject RIV: GJ - Animal Vermins ; Diseases, Veterinary Medicine Impact factor: 2.327, year: 2013

  17. MULTIPLICATION OF DENGUE AND CHIKUNGUNYA VIRUSES IN AEDES MOSQUITOES

    OpenAIRE

    Soedarto Soekiman

    2012-01-01

    Colonies of Aedes aegypti (Surabaya strain) and Aedes albopictus (Malang strain) were studied to compare their susceptibility to oral infection with dengue type 3 and Chikungunya viruses. Growth curves of dengue type 3 and Chikungunya viruses in these mosquitoes indicated that both mosquito species were susceptible to oral infection with these viruses. Electron microscopic observation of the salivary glands of A. aegypti and A. albopictus infected with Chikungunya virus showed that this organ...

  18. Control methods against invasive Aedes mosquitoes in Europe : a review

    OpenAIRE

    Baldacchino, F; Caputo, B.; Chandre, Fabrice; Drago, A.; A. Della Torre; Montarsi, F.; Rizzoli, A.

    2015-01-01

    Five species of invasive Aedes mosquitoes have recently become established in Europe: Ae. albopictus, Ae. aegypti, Ae. japonicus japonicus, Ae. koreicus and Ae. atropalpus. These mosquitoes are a serious nuisance for people and are also competent vectors for several exotic pathogens such as dengue and chikungunya viruses. As they are a growing public health concern, methods to control these mosquitoes need to be implemented to reduce their biting and their potential for disease transmission. ...

  19. Control methods against invasive Aedes mosquitoes in Europe: a review.

    Science.gov (United States)

    Baldacchino, Frédéric; Caputo, Beniamino; Chandre, Fabrice; Drago, Andrea; della Torre, Alessandra; Montarsi, Fabrizio; Rizzoli, Annapaola

    2015-11-01

    Five species of invasive Aedes mosquitoes have recently become established in Europe: Ae. albopictus, Ae. aegypti, Ae. japonicus japonicus, Ae. koreicus and Ae. atropalpus. These mosquitoes are a serious nuisance for people and are also competent vectors for several exotic pathogens such as dengue and chikungunya viruses. As they are a growing public health concern, methods to control these mosquitoes need to be implemented to reduce their biting and their potential for disease transmission. There is a crucial need to evaluate methods as part of an integrated invasive mosquito species control strategy in different European countries, taking into account local Aedes infestations and European regulations. This review presents the control methods available or in development against invasive Aedes mosquitoes, with a particular focus on those that can be implemented in Europe. These control methods are divided into five categories: environmental (source reduction), mechanical (trapping), biological (e.g. copepods, Bacillus thuringiensis var. israelensis, Wolbachia), chemical (insect growth regulators, pyrethroids) and genetic (sterile insect technique and genetically modified mosquitoes). We discuss the effectiveness, ecological impact, sustainability and stage of development of each control method. PMID:26037532

  20. Yellow Fever Virus Infectivity for Bolivian Aedes aegypti Mosquitoes

    OpenAIRE

    Mutebi, John-Paul; Gianella, Alberto; Travassos da Rosa, Amelia; Tesh, Robert B; Barrett, Alan D. T.; Higgs, Stephen

    2004-01-01

    The absence of urban yellow fever virus (YFV) in Bolivian cities has been attributed to the lack of competent urban mosquito vectors. Experiments with Aedes aegypti from Santa Cruz, Bolivia, demonstrated infection (100%), dissemination (20%), and transmission of a Bolivian YFV strain (CENETROP-322).

  1. Rainfall triggered dynamics of Aedes mosquito aggressiveness

    OpenAIRE

    P.I. Ndiaye; Bicout, D J; Mondet, Bernard; Sabatier, P.

    2006-01-01

    Inspired by Davidson method of estimating daily survivals of a structureless population of mosquitoes, we present a model which describes the behavior of floodwater mosquitoes in terms of emergence functions following a rainfall event, blood feeding frequency and parous stages, and survival at various stages. As a generalization of the Davidson formula, we have developed an approach for dealing with the dynamics of structured population of mosquitoes, and derived various formulas allowing ass...

  2. 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...

  3. Factors influencing stakeholders attitudes toward genetically modified aedes mosquito.

    Science.gov (United States)

    Amin, Latifah; Hashim, Hasrizul

    2015-06-01

    Dengue fever is a debilitating and infectious disease that could be life-threatening. It is caused by the dengue virus which affects millions of people in the tropical area. Currently, there is no cure for the disease as there is no vaccine available. Thus, prevention of the vector population using conventional methods is by far the main strategy but has been found ineffective. A genetically modified (GM) mosquito is among the favoured alternatives to curb dengue fever in Malaysia. Past studies have shown that development and diffusion of gene technology products depends heavily upon public acceptance. The purpose of this study is to identify the relevant factors influencing stakeholders' attitudes toward the GM Aedes mosquito and to analyse the relationships between all the factors using the structural equation model. A survey was carried out on 509 respondents from various stakeholder groups in the Klang Valley region of Malaysia. Results of the survey have confirmed that public perception towards complex issues such as gene technology should be seen as a multi-faceted process. The perceived benefit-perceived risk balance is very important in determining the most predominant predictor of attitudes toward a GM mosquito. In this study the stakeholders perceived the benefit of the GM mosquito as outweighing its risk, translating perceived benefit as the most important direct predictor of attitudes toward the GM mosquito. Trust in key players has a direct influence on attitudes toward the GM mosquito while moral concern exhibited an indirect influence through perceived benefits. Other factors such as attitudes toward technology and nature were also indirect predictors of attitudes toward the GM mosquito while religiosity and engagement did not exhibited any significant roles. The research findings serve as a useful database to understand public acceptance and the social construct of public attitudes towards the GM mosquito to combat dengue. PMID:24906652

  4. "MOSQUITO FAUNA OF IRAN I- AEDES (DIPTERA: CULICIDAE "

    Directory of Open Access Journals (Sweden)

    M.Zaim

    1984-06-01

    Full Text Available Biological research of all kinds on mosquitoes must be built upon a foundation of correct identification and sound classification. Except for the anopheline vectors of malaria, relatively little is known about other mosquitoes in Iran and other countries in Southwest Asia. In view of this a comprehensive study on the mosquito fauna of Iran has started since 1981. In this report the list of the Aedes species of Iran is updated. Previous studies by Iranian and foreign investigators have revealed the occurrence of 6 Aedes species in Iran. Ae. vexans, Ae. geniculatus, Ae. caballus, Ae. Caspius, Ae pulchritarsis and Ae. aegypti. In the present study not only all named species, except one, were recollected but 5 additional species were also captured which formerly have not been know to occur in Iran. These species are Ae. Vittatus, Ae. echinus, Ae. detritus, Ae. flavescens, and Ae. leucomelas. Ae. aegypti has not been collected in Iran since the previous report in 1946. The present list of 10 species should not be regarded as final since other species, which occur in neighboring countries, may eventually be found in Iran.

  5. Susceptibility of Aedes flavopictus miyarai and Aedes galloisi mosquito species in Japan to dengue type 2 virus

    Institute of Scientific and Technical Information of China (English)

    Raweewan Srisawat; Ikuo Takashima; Tomohiko Takasaki; Ichiro Kurae; Narihiro Narita; Takashi Kobayashi; Yuki Eshita; Thipruethai Phanitchat; Narumon Komalamisra; Naoki Tamori; Lucky Runtuwene; Kaori Noguchi; Kyoko Hayashida; Shinya Hidano; Naganori Kamiyama

    2016-01-01

    Objective: To evaluate the potential of local mosquitoes to act as vectors for dengue transmission in Japan. Methods: Serotype 2 ThNH28/93 was used to test the dengue susceptibility profiles of Aedes flavopictus miyarai (Ae. f. miyarai), Aedes galloisi (Ae. galloisi) and Aedes albopictus (Ae. albopictus), which were collected in Japan. We used Aedes aegypti from Thailand as a positive control. The mosquitoes were infected with the virus intrathoracically or orally. At 10 or 14 days post infection, the mosquitoes were dissected and total RNA was extracted from their abdomens, thoraxes, heads and legs. Mosquito susceptibility to dengue virus was evaluated using RT-PCR with dengue virus-specific primers. Differences in the infection and mortality rates of the different mosquito species were tested using Fisher's exact probability test. Results: The infection rates for dengue virus administered intrathoracically to Ae. f. miyarai, Ae. galloisi and Aedes aegypti mosquitoes were identical by RT-PCR on Day 10 post infection. All of the body parts we tested were RT-PCR-positive for dengue virus. For the orally admin-istered virus, the infection rates in the different body parts of the Ae. f. miyarai mosquitoes were slightly higher than those of Ae. albopictus mosquitoes, but were similar to the control mosquitoes (P>0.05). The mortality rates for Ae. f. miyarai and Ae. albopictus mosquitoes were similar (P=0.19). Our data indicated that dengue virus was able to replicate and disseminate to secondary infection sites in all of the four mosquito species (Japanese and Thai). Conclusions: Ae. albopictus is a well-known candidate for dengue transmission in Japan. However, our data suggest that Ae. f. miyarai from Ishigaki Island (near Okinawa Island) and Ae. galloisi from Hokkaido (Northern Japan) should also be regarded as potential vectors for dengue transmission in these regions. Further studies on these mosquitoes should be conducted.

  6. 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

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

    Science.gov (United States)

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

    2013-01-01

    The mosquito Aedes aegypti is an epidemic vector of several diseases such as dengue fever and yellow fever. Several pesticides are used to control the mosquito population. Because of their frequent use, some mosquitoes have developed resistance. In this study, we used the Y-tube olfactometer to test essential oils of Cymbopogon species and screened specific formulas of components as repellents against Ae. aegypti. At 400 μL, the extracted oil of citronella grass (Cymbopogon nardus) and myrcene produced a low-active response by inhibiting mosquito host-seeking activity. Citronella grass, lemon grass (Cymbopogon citratus), citral and myrcene also produced a low-treatment response to repellents, for more potential to affect host-seeking behavior. Furthermore, the mixture of citral, myrcene, and citronellal oil (C:M:Ci = 6:4:1) greatly affected and inhibited host-seeking behavior (76% active response; 26% treatment response with 40 μL; 42.5%, 18% with 400 μL; and 19%, 23% with 1000 μL). As compared with the result for N,N-diethyl-3-methylbenzamide (DEET; 44%, 22% with 400 μL), adjusting the composition formulas of citronella oil had a synergistic effect, for more effective repellent against Ae. aegypti. PMID:23998314

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

    Institute of Scientific and Technical Information of China (English)

    NANNAN LIU; QIANG XU; LEE ZHANG

    2006-01-01

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

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

    Science.gov (United States)

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

    2016-03-01

    Mosquitoes transmit a variety of pathogens that have devastating consequences for global public and veterinary health. Despite their capacity to serve as vectors, these insects have a robust capacity to respond to invading organisms with strong cellular and humoral immune responses. In Egypt, Aedes caspius (Pallas, 1771) has been suspected to act as a bridge vector of Rift Valley Fever virus between animals and humans. Microscopic analysis of Ae. caspius hemolymph revealed the presence of phagocytic cells called granulocytes. We further evaluated cellular immune responses produced by Ae. caspius as a result of exposure to a Gram-negative, and Gram-positive bacterium, and to latex beads. After challenge, a rapid and strong phagocytic response against either a natural or synthetic invader was evident. Hemocyte integrity in bacteria-inoculated mosquitoes was not morphologically affected. The number of circulating granulocytes decreased with age, reducing the overall phagocytic capacity of mosquitoes over time. The magnitude and speed of the phagocytic response suggested that granulocytes act as an important force in the battle against foreign invaders, as has been characterized in other important mosquito vector species. PMID:26792848

  10. Host-feeding patterns of potential mosquito vectors in Connecticut, U.S.A.: molecular analysis of bloodmeals from 23 species of Aedes, Anopheles, Culex, Coquillettidia, Psorophora, and Uranotaenia.

    Science.gov (United States)

    Molaei, Goudarz; Andreadis, Theodore G; Armstrong, Philip M; Diuk-Wasser, Maria

    2008-11-01

    We evaluated the blood-feeding patterns in several mosquito species that may serve as vectors of disease agents in the northeastern United States. Blood-fed mosquitoes were collected from 91 different sites throughout Connecticut over a 6-yr period (June-October 2002-2007), and the host-feeding patterns of 23 mosquito species representing six genera were examined by using a polymerase chain reaction-based assay and sequencing portions of the cytochrome b gene of mitochondrial DNA. This study was part of a statewide surveillance program and for some of the mosquito species a limited number of specimens were examined [e.g., Aedes communis (De Geer) (1), Anopheles barberi Coquillett (1), Uranotaenia sapphirina (Osten Sacken) (5)]. With the exception of Culex territans Walker that acquired bloodmeals from all four classes of vertebrates--birds, reptiles, amphibians, and mammals--all species of Aedes, Anopheles, Coquillettidia, Psorophora, and to a lesser degree, Uranotaenia, were found to feed predominately upon mammalian hosts. Fourteen mammalian species were identified as sources of blood, but the majority of feedings were taken from the white-tailed deer, Odocoileus virginianus. Human-derived bloodmeals were identified from 13 of the 23 mosquito species. Limited avian-derived bloodmeals were detected in Aedes canadensis (Theobald), Aedes cantator (Coquillett), Aedes cinereus Meigen, Aedes triseriatus (Coquillett), Aedes trivittatus (Coquillett), Coquillettidia perturbans (Walker) Cx. territans, Psorophoraferox (von Humboldt), and Ur. sapphirina. American robin, Turdus migratorius, was the most common source of avian blood, followed by a few other mostly Passeriformes birds. We conclude that the white-tailed deer serve as the main vertebrate host for these mammalophilic mosquitoes in this region of the United States. This feeding pattern supports enzootic amplification of arboviruses, including Jamestown Canyon, Cache Valley, and Potosi viruses that perpetuate in

  11. 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...

  12. The invasive mosquito Aedes japonicus in Central Europe.

    Science.gov (United States)

    Schaffner, F; Kaufmann, C; Hegglin, D; Mathis, A

    2009-12-01

    Complaints about a biting pest led to the recognition of invasive Aedes (Finlaya) japonicus japonicus (Theobald) (Diptera: Culicidae) in Central Europe. Larval collections from cemetery vases revealed a colonized area of approximately 1400 km(2) in northern Switzerland spreading into bordering Germany, suggesting that the mosquito has been established in this region for several years. Within this range, larvae of Ae. japonicus were recovered from more containers than the most common resident culicid species Culex pipiens. Possible introduction sites (used tyre yards and international airports) revealed few or no larvae, and the mode of introduction remains unclear. Given the vector potential of this species for arboviruses, implementation of surveillance and control measures should be considered. PMID:19941611

  13. 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...

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

    Directory of Open Access Journals (Sweden)

    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.

  15. 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.

  16. 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

  17. Potency of Pandanus amaryllifolius and Notophanax scutellarium as Aedes albopictus Mosquito Repellent

    OpenAIRE

    Rina Marina; Endang Puji Astuti

    2012-01-01

    Aedes aegypti and Ae. albopictus mosquitoes being the vector of Dengue Haemorrhagic Fever (DHF). Various effort have been done to control the mosquitoes, including using plant extract as repellent. Pandanus amaryllifolius and Notophanax scutellarium leaf were known to posses repellent activity for mosquito species. The study aimed to examine efJectiveness of P. amaryllifolius and N. scutellarium leaves as repellent for Ae. albopictus. The result study on 1 hr treatment showed that power prote...

  18. Preliminary Analysis of Several Attractants and Spatial Repellents for the Mosquito, Aedes albopictus using an Olfactometer

    OpenAIRE

    Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

    2012-01-01

    Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Further...

  19. Chikungunya Virus Replication in Salivary Glands of the Mosquito Aedes albopictus

    Directory of Open Access Journals (Sweden)

    Anubis Vega-Rúa

    2015-11-01

    Full Text Available Chikungunya virus (CHIKV is an emerging arbovirus transmitted to humans by mosquitoes such as Aedes albopictus. To be transmitted, CHIKV must replicate in the mosquito midgut, then disseminate in the hemocele and infect the salivary glands before being released in saliva. We have developed a standardized protocol to visualize viral particles in the mosquito salivary glands using transmission electron microscopy. Here we provide direct evidence for CHIKV replication and storage in Ae. albopictus salivary glands.

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

    Directory of Open Access Journals (Sweden)

    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

  1. COEXISTENCE, EXCLUSION, OR NEUTRALITY? A META-ANALYSIS OF COMPETITION BETWEEN AEDES ALBOPICTUS AND RESIDENT MOSQUITOES

    OpenAIRE

    Juliano, Steven A.

    2010-01-01

    Competition experiments estimating the relative effects of inter- and intraspecific competition can help to resolve whether interspecific competition results in coexistence or exclusion. For mosquitoes, most such experiments have focused on invasive Aedes albopictus and its interactions with resident Aedes. A meta-analysis of such experiments tested whether the effect of interspecific competition is greater than, less than, or equal to that of intraspecific competition, and whether competitiv...

  2. 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...

  3. Aedes aegypti (Diptera : Culicidae) in Mauritania : first report on the presence of the arbovirus mosquito vector in Nouakchott

    OpenAIRE

    Lekweiry, K.M.; Ould Ahmedou Salem, M. S.; Ould Brahim, K.; Lemrabott, M. A. O.; Brengues, Cécile; Faye, O.; Simard, Frédéric; Ould Mohamed Salem Boukhary, A.

    2015-01-01

    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 c...

  4. Larval mosquito habitat utilization and community dynamics of Aedes albopictus and Aedes japonicus (Diptera: Culicidae).

    Science.gov (United States)

    Bartlett-Healy, Kristen; Unlu, Isik; Obenauer, Peter; Hughes, Tony; Healy, Sean; Crepeau, Taryn; Farajollahi, Ary; Kesavaraju, Banu; Fonseca, Dina; Schoeler, George; Gaugler, Randy; Strickman, Daniel

    2012-07-01

    Aedes albopictus (Skuse) and Ae. japonicus (Theobald) are important container-inhabiting mosquitoes that transmit disease agents, outcompete native species, and continue to expand their range in the United States. Both species deposit eggs in natural and artificial containers and thrive in peridomestic environments. The goal of our study was to examine the types and characteristics of containers that are most productive for these species in the northeastern United States. In total, 306 containers were sampled in urban, suburban, and rural areas of New Jersey. Multiple biotic and abiotic factors were recorded in an attempt to identify variables associated with the productivity of each species. Based on pupal abundance and density of container types, results showed that tires, trash cans, and planter dishes were the most important containers for Ae. albopictus, while planter dishes were the most important containers for Ae. japonicus. Container color (black and gray), material (rubber), and type (tires) were correlated with species presence for Ae. albopictus and Ae. japonicus. These factors may play a role in the selection of oviposition sites by female mosquitoes or in the survival of their progeny. Differences in species composition and abundance were detected between areas classified as urban, suburban, and rural. In urban and suburban areas, Ae. albopictus was more abundant in container habitats than Ae. japonicus; however, Ae. japonicus was more abundant in rural areas, and when water temperatures were below 14 degrees C. Our results suggest many variables can influence the presence of Ae. albopictus and Ae. japonicus in container habitats in northeastern United States. PMID:22897041

  5. 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 ...

  6. Detection of dengue virus in individual Aedes aegypti mosquitoes in Delhi, India

    Directory of Open Access Journals (Sweden)

    Kumar Vikram

    2015-01-01

    Interpretation & conclusion: The study concludes that there was high MIR in the identified localities of low and medium income groups. Estimation of MIR in a female Aedes mosquito in the existing arsenals for dengue surveillance would be an added advantage for early warning of dengue outbreak. The presence of infected mosquitoes in identified localities of Delhi was alarming and require rigorous vector surveillance so that the severe outbreaks can be prevented.

  7. 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...

  8. Potential of selected Senegalese Aedes spp. mosquitoes (Diptera: Culicidae) to transmit Zika virus

    OpenAIRE

    Diagne, Cheikh Tidiane; Diallo, Diawo; Faye, Oumar; Ba, Yamar; Gaye, Alioune; Dia, Ibrahima; Faye, Ousmane; Weaver, Scott C.; Sall, Amadou Alpha; Diallo, Mawlouth

    2015-01-01

    Background Zika virus (ZIKV; genus Flavivirus, family Flaviviridae) is an emerging virus of medical importance maintained in a zoonotic cycle between arboreal Aedes spp. mosquitoes and nonhuman primates in African and Asian forests. Serological evidence and virus isolations have demonstrated widespread distribution of the virus in Senegal. Several mosquito species have been found naturally infected by ZIKV but little is known about their vector competence. Methods We assessed the vector compe...

  9. Zoonotic Dirofilaria repens (Nematoda: Filarioidea) in Aedes vexans mosquitoes, Czech Republic

    Czech Academy of Sciences Publication Activity Database

    Rudolf, Ivo; Šebesta, Oldřich; Mendel, Jan; Betášová, Lenka; Bocková, E.; Jedličková, Petra; Venclíková, Kristýna; Blažejová, Hana; Šikutová, Silvie; Hubálek, Zdeněk

    2014-01-01

    Roč. 113, č. 12 (2014), s. 4663-4667. ISSN 0932-0113 EU Projects: European Commission(XE) 261504 - EDENEXT Institutional support: RVO:68081766 Keywords : Aedes vexans * Mosquito vectors * Dirofilaria repens * Dogs * Zoonotic dirofilariosis * Setaria spp. Subject RIV: EG - Zoology Impact factor: 2.098, year: 2014

  10. 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...

  11. 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

  12. Zika virus in Brazil and the danger of infestation by Aedes (Stegomyia mosquitoes

    Directory of Open Access Journals (Sweden)

    Carlos Brisola Marcondes

    2015-01-01

    Full Text Available Abstract Zika virus, already widely distributed in Africa and Asia, was recently reported in two Northeastern Brazilian: State of Bahia and State of Rio Grande do Norte, and one Southeastern: State of São Paulo. This finding adds a potentially noxious virus to a list of several other viruses that are widely transmitted by Aedes (Stegomyia aegypti and Aedes (Stegomyia albopictus in Brazil. The pathology and epidemiology, including the distribution and vectors associated with Zika virus, are reviewed. This review is focused on viruses transmitted by Aedes (Stegomyia mosquitoes, including dengue, Chikungunya, Zika, Mayaro, and yellow fever virus, to emphasize the risks of occurrence for these arboviruses in Brazil and neighboring countries. Other species of Aedes (Stegomyia are discussed, emphasizing their involvement in arbovirus transmission and the possibility of adaptation to environments modified by human activities and introduction in Brazil.

  13. Zika virus in Brazil and the danger of infestation by Aedes (Stegomyia) mosquitoes.

    Science.gov (United States)

    Marcondes, Carlos Brisola; Ximenes, Maria de Fátima Freire de Melo

    2016-02-01

    Zika virus, already widely distributed in Africa and Asia, was recently reported in two Northeastern Brazilian: State of Bahia and State of Rio Grande do Norte, and one Southeastern: State of São Paulo. This finding adds a potentially noxious virus to a list of several other viruses that are widely transmitted by Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus in Brazil. The pathology and epidemiology, including the distribution and vectors associated with Zika virus, are reviewed. This review is focused on viruses transmitted by Aedes (Stegomyia) mosquitoes, including dengue, Chikungunya, Zika, Mayaro, and yellow fever virus, to emphasize the risks of occurrence for these arboviruses in Brazil and neighboring countries. Other species of Aedes (Stegomyia) are discussed, emphasizing their involvement in arbovirus transmission and the possibility of adaptation to environments modified by human activities and introduction in Brazil. PMID:26689277

  14. 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

  15. Potency of Pandanus amaryllifolius and Notophanax scutellarium as Aedes albopictus Mosquito Repellent

    Directory of Open Access Journals (Sweden)

    Rina Marina

    2012-12-01

    Full Text Available Aedes aegypti and Ae. albopictus mosquitoes being the vector of Dengue Haemorrhagic Fever (DHF. Various effort have been done to control the mosquitoes, including using plant extract as repellent. Pandanus amaryllifolius and Notophanax scutellarium leaf were known to posses repellent activity for mosquito species. The study aimed to examine efJectiveness of P. amaryllifolius and N. scutellarium leaves as repellent for Ae. albopictus. The result study on 1 hr treatment showed that power protection of pandan leaves (N. scutellarium was 93.55%, while mangkokan leaves (P. amaryllifolius was 87.5%. Based on ANOVA analysis, there was not significantly different of power protection between N. scutellarium leaves and P. amaryllifolius leaves extracts against Ae. albopictus mosquitoes. Both of these test, plants has showed the potential to be a repellent and eliminate the emergence of Ae. albopictus mosquitoes, so it may effectively reduce contact between host and dengue vector.

  16. 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

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

    Directory of Open Access Journals (Sweden)

    Leon E Hugo

    2014-02-01

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

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

    Science.gov (United States)

    Arbaoui, A A; Chua, T H

    2014-03-01

    Since a safe and effective mass vaccination program against dengue fever is not presently available, a good way to prevent and control dengue outbreaks depends mainly on controlling the mosquito vectors. Aedes aegypti mosquito populations can be monitored and reduced by using ovitraps baited with organic infusions. A series of laboratory experiments were conducted which demonstrated that the bacteria in bamboo leaf infusion produce volatile attractants and contact chemical stimulants attractive to the female mosquitoes. The results showed that the female mosquitoes laid most of their eggs (59.9 ± 8.1 vs 2.9 ± 2.8 eggs, P<0.001) in bamboo leaf infusions when compared to distilled water. When the fresh infusion was filtered with a 0.45 μm filter membrane, the female mosquitoes laid significantly more eggs (64.1 ± 6.6 vs 4.9 ± 2.6 eggs, P<0.001) in unfiltered infusion. However when a 0.8 μm filter membrane was used, the female laid significantly more eggs (62.0 ± 4.3 vs 10.1 ± 7.8 eggs, P<0.001) in filtrate compared to a solution containing the residue. We also found that a mixture of bacteria isolated from bamboo leaf infusion serve as potent oviposition stimulants for gravid Aedes mosquitoes. Aedes aegypti laid significantly more eggs (63.3 ± 6.5 vs 3.1 ± 2.4 eggs, P<0.001) in bacteria suspension compared to sterile R2A medium. Our results suggest microbial activity has a role in the production of odorants that mediate the oviposition response of gravid mosquitoes. PMID:24862053

  19. 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...

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

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    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.

  1. miRNA genes of an invasive vector mosquito, Aedes albopictus.

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    Jinbao Gu

    Full Text Available Aedes albopictus, a vector of Dengue and Chikungunya viruses, is a robust invasive species in both tropical and temperate environments. MicroRNAs (miRNAs regulate gene expression and biological processes including embryonic development, innate immunity and infection. While a number of miRNAs have been discovered in some mosquitoes, no comprehensive effort has been made to characterize them from different developmental stages from a single species. Systematic analysis of miRNAs in Ae. albopictus will improve our understanding of its basic biology and inform novel strategies to prevent virus transmission. Between 10-14 million Illumina sequencing reads per sample were obtained from embryos, larvae, pupae, adult males, sugar-fed and blood-fed adult females. A total of 119 miRNA genes represented by 215 miRNA or miRNA star (miRNA* sequences were identified, 15 of which are novel. Eleven, two, and two of the newly-discovered miRNA genes appear specific to Aedes, Culicinae, and Culicidae, respectively. A number of miRNAs accumulate predominantly in one or two developmental stages and the large number that showed differences in abundance following a blood meal likely are important in blood-induced mosquito biology. Gene Ontology (GO analysis of the targets of all Ae. albopictus miRNAs provides a useful starting point for the study of their functions in mosquitoes. This study is the first systematic analysis of miRNAs based on deep-sequencing of small RNA samples of all developmental stages of a mosquito species. A number of miRNAs are related to specific physiological states, most notably, pre- and post-blood feeding. The distribution of lineage-specific miRNAs is consistent with mosquito phylogeny and the presence of a number of Aedes-specific miRNAs likely reflects the divergence between the Aedes and Culex genera.

  2. 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.

  3. 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.

  4. Limited dengue virus replication in field-collected Aedes aegypti mosquitoes infected with Wolbachia.

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    Francesca D Frentiu

    2014-02-01

    Full Text Available INTRODUCTION: Dengue is one of the most widespread mosquito-borne diseases in the world. The causative agent, dengue virus (DENV, is primarily transmitted by the mosquito Aedes aegypti, a species that has proved difficult to control using conventional methods. The discovery that A. aegypti transinfected with the wMel strain of Wolbachia showed limited DENV replication led to trial field releases of these mosquitoes in Cairns, Australia as a biocontrol strategy for the virus. METHODOLOGY/PRINCIPAL FINDINGS: Field collected wMel mosquitoes that were challenged with three DENV serotypes displayed limited rates of body infection, viral replication and dissemination to the head compared to uninfected controls. Rates of dengue infection, replication and dissemination in field wMel mosquitoes were similar to those observed in the original transinfected wMel line that had been maintained in the laboratory. We found that wMel was distributed in similar body tissues in field mosquitoes as in laboratory ones, but, at seven days following blood-feeding, wMel densities increased to a greater extent in field mosquitoes. CONCLUSIONS/SIGNIFICANCE: Our results indicate that virus-blocking is likely to persist in Wolbachia-infected mosquitoes after their release and establishment in wild populations, suggesting that Wolbachia biocontrol may be a successful strategy for reducing dengue transmission in the field.

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

    Science.gov (United States)

    Monaghan, Andrew J.; Morin, Cory W.; Steinhoff, Daniel F.; Wilhelmi, Olga; Hayden, Mary; Quattrochi, Dale A.; Reiskind, Michael; Lloyd, Alun L.; 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 analyzed alongside travel and socioeconomic factors that are proxies of viral introduction and vulnerability to human-vector contact.     Results: Meteorological conditions are largely unsuitable for Aedes aegypti over the U.S. during winter months (December-March), except in southern Florida and south Texas where comparatively warm conditions can sustain low-to-moderate potential mosquito abundance. Meteorological conditions are suitable for Aedes aegypti across all fifty cities during peak summer months (July-September), though the mosquito has not been documented in all cities. Simulations indicate the highest mosquito abundance occurs in the Southeast and south Texas where locally acquired cases of Aedes-transmitted viruses have been reported previously. Cities in southern Florida and south Texas are at the nexus of high seasonal suitability for Aedes aegypti and strong potential for travel-related virus introduction. Higher poverty rates in cities along the U.S.-Mexico border may correlate with factors that increase human exposure to Aedes aegypti.     Discussion: Our results can inform baseline risk for local Zika virus transmission in the U.S. and the optimal timing of vector control activities, and underscore the need for enhanced surveillance for Aedes mosquitoes and Aedes-transmitted viruses. PMID:27066299

  6. 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 ...

  7. The Dengue Virus Mosquito Vector Aedes aegypti at High Elevation in México

    OpenAIRE

    Lozano-Fuentes, Saul; Hayden, Mary H.; Welsh-Rodriguez, Carlos; Ochoa-Martinez, Carolina; Tapia-Santos, Berenice; Kobylinski, Kevin C.; Uejio, Christopher K.; Zielinski-Gutierrez, Emily; Monache, Luca Delle; Monaghan, Andrew J; Steinhoff, Daniel F; Eisen, Lars

    2012-01-01

    México has cities (e.g., México City and Puebla City) located at elevations > 2,000 m and above the elevation ceiling below which local climates allow the dengue virus mosquito vector Aedes aegypti to proliferate. Climate warming could raise this ceiling and place high-elevation cities at risk for dengue virus transmission. To assess the elevation ceiling for Ae. aegypti and determine the potential for using weather/climate parameters to predict mosquito abundance, we surveyed 12 communities ...

  8. Results of a survey to detect the mosquito Aedes albopictus in the French Riviera.

    Science.gov (United States)

    Fauran, P; Marty, P; Izri, M A; Le Fichoux, Y

    1998-09-01

    A programme of surveillance was initiated in 1992, in the French Riviera, to detect a possible introduction of Aedes albopictus from Italy and to prevent nuisances caused by mosquitoes in the touristic localities of the Côte d'Azur. In five years, numerous mosquito breeding places have been located. Nine species have been collected: Anopheles claviger, An. plumbeus, Aedes geniculatus, Ae. vittatus, Culex hortensis, Cx. impudicus, Cx. pipiens, Culiseta fumipennis, Cs. longiareolata but no Ae. albopictus was found. Nuisances were mainly due to hypogean populations of Cx. pipiens. Breeding places in urban sites have been controlled or suppressed. The discovery of an important larval population of An. plumbeus in an urban area might further stress the importance of this species already suspected to transmit indigenous malaria in cities. PMID:10376290

  9. Proteomic profiling of a robust Wolbachia infection in an Aedes albopictus mosquito cell line

    OpenAIRE

    Baldridge, Gerald D; Baldridge, Abigail S.; Witthuhn, Bruce A.; Higgins, LeeAnn; Markowski, Todd W.; FALLON, ANN M.

    2014-01-01

    Wolbachia pipientis a widespread vertically transmitted intracellular bacterium, provides a tool for insect control through manipulation of host-microbe interactions. We report proteomic characterization of wStr, a Wolbachia strain associated with a strong cytoplasmic incompatibility phenotype in its native host, Laodelphax striatellus. In the Aedes albopictus C/wStr1 mosquito cell line, wStr maintains a robust, persistent infection. MS/MS analyses of gel bands revealed a protein “footprint” ...

  10. Invasive leaf resources alleviate density dependence in the invasive mosquito, Aedes albopictus

    OpenAIRE

    Reiskind, Michael H.; Zarrabi, Ali A.; LOUNIBOS, L. PHILIP

    2009-01-01

    Interactions between invasive species can have important consequences for the speed and impact of biological invasions. Containers occupied by the invasive mosquito, Aedes albopictus Skuse, may be sensitive to invasive plants whose leaves fall into this larval habitat. To examine the potential for interactions between invasive leaf species and larval A. albopictus, we conducted a field survey of leaf material found with A. albopictus in containers in Palm Beach County, Florida and measured de...

  11. The molecular physiology of increased egg desiccation resistance during diapause in the invasive mosquito, Aedes albopictus

    OpenAIRE

    Urbanski, Jennifer M.; BENOIT, JOSHUA B.; Michaud, M. Robert; Denlinger, David L.; Armbruster, Peter

    2010-01-01

    Photoperiodic diapause is a crucial adaptation to seasonal environmental variation in a wide range of arthropods, but relatively little is known regarding the molecular basis of this important trait. In temperate populations of the mosquito Aedes albopictus, exposure to short-day (SD) lengths causes the female to produce diapause eggs. Tropical populations do not undergo a photoperiodic diapause. We identified a fatty acyl coA elongase transcript that is more abundant under SD versus long-day...

  12. 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...

  13. 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...

  14. 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...

  15. 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...

  16. Differential responses of the mosquito Aedes albopictus from the Indian Ocean region to two chikungunya isolates

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    Failloux Anna-Bella

    2010-03-01

    Full Text Available Abstract Background Aedes aegypti and Aedes albopictus are both vectors of chikungunya virus (CHIKV. The two Aedes species co-exist in the Indian Ocean region and were involved in the 2005-2006 CHIKV outbreaks. In the Reunion Island, a single mutation in the viral envelope has been selected that leads to high levels of replication in Ae. albopictus, and a short extrinsic incubation period as the virus could be found in saliva as early as two days after infection. An important question is whether this variant is associated with adverse effects impacting some mosquito life-history traits such as survival and reproduction. Results We performed experimental infections using three mosquito strains of Ae. aegypti Mayotte and Ae. albopictus (Mayotte and Reunion, and two CHIKV strains (E1-226A and E1-226V. Ae. aegypti Mayotte were similarly susceptible to both viral strains, whereas Ae. albopictus Mayotte and Ae. albopictus Reunion were more susceptible to CHIKV E1-226V than to E1-226A. In terms of life-history traits measured by examining mosquito survival and reproduction, we found that: (1 differences were observed between responses of mosquito species to the two viruses, (2 CHIKV infection only affected significantly some life-history traits of Ae. albopictus Reunion and not of the other two mosquito strains, and (3 CHIKV reduced the lifespan of Ae. albopictus Reunion and shortened the time before egg laying. Conclusion We demonstrated that CHIKV only reduces the survival of Ae. albopictus from the Reunion Island. By laying eggs just before death, reproduction of Ae. albopictus from the Reunion Island is not reduced since other parameters characterizing oviposition and hatching were not affected.

  17. 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

  18. 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.

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

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    Ashish Uniyal

    2016-01-01

    Full Text Available 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 in laboratory conditions using Y-tube olfactometer.  Results: The essential oils exhibited varying degree of repellency. Litsea oil showed 50.31%, 60.2 %, and 77.26% effective mean repellency at 1 ppm, 10 ppm and 100 ppm respectively, while DEET exhibited 59.63%, 68.63%, 85.48% and DEPA showed 57.97%, 65.43%, and 80.62% repellency at respective above concentrations. Statistical analysis revealed that among the tested essential oils, litsea oil had effective repellency in comparison with DEET and DEPA against Ae. aegypti mosquito at all concentration. Essential oils, DEET and DEPA showed significant repellence against Ae. aegypti (P< 0.05 at all 3 concentration tested.Conclusion: Litsea oil exhibited effective percentage repellency similar to DEET and DEPA. The essential oils are natural plant products that may be useful for developing safer and newer herbal based effective mosquito repellents.

  20. Control of DF/DHF Vector, Aedes Mosquito, with Insecticides

    OpenAIRE

    Itoh, Takaaki

    1994-01-01

    Aedes aegypti, the principal vector of DF/DHF, mainly breeds in household water jars. The breeding sites are definite and, thus, the larviciding will become the most effective measures as well as source reduction. However, the following facts make it difficult. 1) Water in the jars is used and refilled. The replenishment of water leads to dilution of larvicides. 2) Many small breeding sites are overlooked, such as water at the bottom of household plant pots. To solve these problems, two new l...

  1. Web mapping GIS: GPS under the GIS umbrella for Aedes species dengue and chikungunya vector mosquito surveillance and control

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    M. Palaniyandi

    2014-09-01

    Full Text Available The mosquito nuisance and the mosquito borne diseases have become major important challenging public health problems in India especially in the fast developing city like Pondicherry urban agglomeration. The Pondicherry government has been implemented full-fledged mosquito control measures, however, dengue and chikungunya epidemics was accelerating trend in Pondicherry for the recent years, and therefore, the directorate of public health, Pondicherry was requested vector control research centre (VCRC, to conduct a mosquito control evaluation survey. A team of field staff of VCRC headed by the author, Pondicherry, have conducted a detailed reconnaissance survey for collecting the site specifications of houses and the streetwise mosquito data for analyzing the density of vector mosquitoes in the wards / blocks and delineating the areas vulnerable to disease epidemics in the urban areas. The GPS GARMIN 12 XL was used to collect the field data. The ARC GIS 10.0 software was used to map the site locations (houses with mosquito’s data. The digital map of block boundary of Pondicherry was used for mapping purpose. A systematic grid sampling was applied to conduct a rapid survey for mapping Aedes species mosquito genic condition in the urban areas and the coordinates of sites of house information with breeding habitats positive in the grid sectors was collected using GPS, and the mean value of positive habitats was analyzed by quintiles method for mapping. The four blocks were selected for Aedes mosquito survey where the mosquito problem was identified as comparatively high, four numbers of wards were selected from each block, and the 40 number of houses was selected with 100 meter interval distance for mosquito breeding survey in the domestic and peripheral domestic areas in each wards. The problematic areas were identified, highlighted and recommended for web mapping GIS for Aedes mosquito surveillance continuously for monitoring the mosquito control

  2. Heritable CRISPR/Cas9-mediated genome editing in the yellow fever mosquito, Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    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.

  3. Repellent Action Of Neem (Azadiracta India Seed Oil Against Aedes Aegypti Mosquitoes

    Directory of Open Access Journals (Sweden)

    Hati A K

    1995-01-01

    Full Text Available 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 mosquitoes alighted on the skin of which 2% only took the blood meal when 2 ml of the oil was used to cover the hand. In the control cages cent percent of the mosquitoes alighted and sucked blood. The repellent action was directly proportional to the hour of exposure to the oil. It was also observed that even after alighting on a oil- smeared skin a sizeable proportion of mosquitoes were not able to imbibe blood meal. Neem seed oil was non-toxic, non- irritating to skin.

  4. Preliminary analysis of several attractants and spatial repellents for the mosquito, Aedes albopictus using an olfactometer.

    Science.gov (United States)

    Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

    2012-01-01

    Mosquito attractants and spatial repellents hold great promise in controlling mosquito pests. In assessing the effectiveness of mosquito attractants and repellents, a good olfactometer system, and optimized testing conditions, are essential. In this research, we demonstrated the usefulness of an olfactometer system, and optimized testing conditions for Aedes albopictus (Diptera: Culicidae). We found no significant difference in the biting activity of the insect between 8:00 and 22:00. Furthermore, 5-10 day old mosquitoes were relatively strongly attracted, with bloodsucking rate 75.8%. The random capture rate (entered trap in absence of odor) was less than 20% for the 20-40 tested insects. Capture rates and systematic errors increased as the number of testing insects increased. Wind speed affected the capture rate significantly, whereas variations in temperature between 25-28°C did not result in significant difference. The wind speed of 0.2 m/s exhibited a higher capture rate, which was significantly different from those at either 0.1 m/s or 0.4 m/s (P mosquitoes to successfully trace human odor or 1% of L-lactic acid in dichloromethane. The results of these two tests indicate that the L-lactic acid/dichloromethane mixture may be used as an effective attractant to evaluate the effect of possible spatial repellents on Ae. albopictus. PMID:23418948

  5. Eco-virological survey of Aedes mosquito larvae in selected dengue outbreak areas in Malaysia

    Directory of Open Access Journals (Sweden)

    A. Rohani

    2014-12-01

    Full Text Available Background & objectivesi: Transovarial transmission of dengue virus in the Aedes vectors is now a well-documented phenomenon reported from many parts of the endemic areas in the world, which played an important role in initiating and maintaining the outbreak in human populations. This study investigated the factors affecting breeding habitats and the relationship with transovarial dengue virus in larvae of Aedes aegypti and Ae. albopictus. Methods: Larval surveillance was conducted in dengue outbreak areas in Malaysia from 2008 until 2009. Sampling was carried out based on habitat type, water condition (substrate type, canopy coverage, temperature and pH at breeding habitats. RT-PCR was performed to detect presence of transovarial dengue virus in larvae collected in the study areas. Results: A total of 789 breeding habitats were identified during this study and the majority of these breeding sites were plastic containers (57.46%. Aedes albopictus dominated most of the water condition surveyed, while Ae. aegypti indicated preference toward habitats with clear water. Aedes aegypti was selective in selecting ovipositional sites compared to Ae. albopictus where shaded areas were shown to be the most preferred. From a total of 363 mosquito larvae pools, 23 (6.3% pools were positive for dengue virus where 18 of them were from Ae. albopictus and five were from Ae. aegypti mosquito larvae pools. Interpretation & conclusion: This study indicated the presence of transovarial transmission of dengue virus in immature Ae. aegypti and Ae. albopictus in the field. This study also showed that combination of water conditions, canopy coverage, temperature and pH of breeding habitats were the factors affecting the larval population. The study suggested that larval survey programme could serve as a tool not only to monitor the local dengue vector distribution but also to provide objective information for taking appropriate action by the community against dengue

  6. An experimental quality control related to the regional monitoring plan against Aedes albopticus (tiger-mosquito

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    Samantha Morelli

    2009-06-01

    Full Text Available Following the epidemic disease caused by the Chikungunya virus detected in the Provinces of Romagna during 2007, a specific monitoring-plan against the bug-vector Aedes albopticus was set up by the Agenzia Regionale Prevenzione e Ambiente dell’Emilia Romagna (ARPA in the he Emilia-Romagna region (Italy. The analytical method consisted in the simple enumeration of the mosquitoes eggs spawned on a appropriate substratum, using an optic microscope.The aim of this study was to guarantee data comparability among the several laboratories involved in the project. Using the Analysis of Variance (ANOVA, homogeneous and comparable analytical data were emphasised.

  7. 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.

  8. Investigation of mosquito oviposition pheromone as lethal lure for the control of Aedes aegypti (L.) (Diptera: Culicidae)

    OpenAIRE

    Ong, Song-Quan; Jaal, Zairi

    2015-01-01

    Background The trend in chemical insecticide development has focused on improving the efficacy against mosquitoes while reducing the environmental impact. Lethal lures apply an “attract-and-kill” strategy that draws the insect to the killing agent rather than bringing the killing agent to the insect. Methods In this study, the mosquito oviposition pheromone was extracted from the eggs of Aedes aegypti (L.) and further investigated with a combination of pheromone and granular temephos as a let...

  9. Effects of intraspecific larval competition on adult longevity in the mosquitoes Aedes aegypti and Aedes albopictus

    OpenAIRE

    Reiskind, M.H.; Lounibos, L. P.

    2009-01-01

    Larval competition is common in container-breeding mosquitoes. The impact of competition on larval growth has been thoroughly examined and findings that larval competition can lead to density-dependent effects on adult body size have been documented. The effects of larval competition on adult longevity have been less well explored. The effects of intraspecific larval densities on the longevity of adults maintained under relatively harsh environmental conditions were tested in the laboratory b...

  10. The effects of x-irradiation in the mosquito Aedes aegypti (L)

    International Nuclear Information System (INIS)

    Newly emerged mosquitoes (Aedes aegypti (L)) were exposed to doses of 500 to 32,000 rad X-irradiation and the LD50 and mean survival time determined. Radiation doses between 500 and 8,000 rad had only a slight effect on longevity whereas exposure to 32,000 had an appreciable effect. The midgut structure of newly emerged, X-irradiated female Aedes aegypti imagines was examined at set intervals after irradiation. The cytochemical localization of midgut acid phosphatase, alkaline phosphatase and adenosine triphosphatase, and also quantitative estimates of midgut acid and alkaline phosphatase were carried out on mosquitoes exposed to 32,000 rad. Considerable changes in the structure of the midgut cells were apparent. With 500, 4,000 and 8,000 rad there was evidence of cellular repair and recovery. However, with 32,000 rad cellular damage was most extensive, with considerable loss of cell structure. The ultrastructural changes noted suggest that the primary radiation damage was to the plasma and organelle membranes, which is in agreement with the membrane-damage/enzyme release hypothesis. (author)

  11. 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...

  12. Gustatory receptor neuron responds to DEET and other insect repellents in the yellow fever mosquito, aedes aegypti

    Science.gov (United States)

    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 DEET and other insect repellents. Two other ...

  13. Importance of socioeconomic status and tree holes in distribution of Aedes mosquitoes (Diptera: Culicidae) in Jodhpur, Rajasthan, India.

    Science.gov (United States)

    Joshi, Vinod; Sharma, R C; Sharma, Yogesh; Adha, Sandeep; Sharma, Keerti; Singh, Himmat; Purohit, Anil; Singhi, Manju

    2006-03-01

    Immature Aedes mosquitoes were found in domestic, peridomestic, and tree hole habitats within three socioeconomic strata of Jodhpur, a city within an arid area of Rajasthan, India, endemic for dengue. Peridomestic habitats served as a persistent source of Aedes vectors, especially those used for watering cows for religious reasons that were located within high socioeconomic areas. Domestic (indoor) containers within low socioeconomic strata showed a higher container index (27.0%) than periurban areas with cattle sheds (14.3%) or high socioeconomic areas (18.1%). Mosquitoes were collected in tree holes at zoos and gardens supporting several species of monkeys. Six of 67 Aedes albopictus Skuse reared from immatures collected in tree holes tested positive for dengue antigen acquired through vertical transmission, possibly indicating a persistence mechanism for dengue virus within an urban environment. PMID:16619619

  14. The Insect Growth Regulator Pyriproxyfen Terminates Egg Diapause in the Asian Tiger Mosquito, Aedes albopictus.

    Science.gov (United States)

    Suman, Devi S; Wang, Yi; Gaugler, Randy

    2015-01-01

    The Asian tiger mosquito, Aedes albopictus, is a highly invasive mosquito species that transmits chikungunya and dengue. This species overwinters as diapausing eggs in temperate climates. Early diapause termination may be a beneficial strategy for winter mosquito control; however, a mechanism to terminate the diapause process using chemicals is not known. We tested the hypothesis that a hormonal imbalance caused by the administration of juvenile hormone analog would terminate egg diapause in A. albopictus. We tested the insect growth regulator pyriproxyfen on all developmental stages to identify a susceptible stage for diapause termination. We found that pyriproxyfen treatment of mosquito eggs terminated embryonic diapause. The highest rates of diapause termination were recorded in newly deposited (78.9%) and fully embryonated (74.7%) eggs at 0.1 and 1 ppm, respectively. Hatching was completed earlier in newly deposited eggs (25-30 days) compared to fully embryonated eggs (71-80 days). The combined mortality from premature diapause termination and ovicidal activity was 98.2% in newly deposited and >98.9% in fully embryonated eggs at 1 ppm. The control diapause eggs did not hatch under diapausing conditions. Pyriproxyfen exposure to larvae, pupae and adults did not prevent the females from ovipositing diapausing eggs. There was no effect of pyriproxyfen on diapausing egg embryonic developmental time. We also observed mortality in diapausing eggs laid by females exposed to pyriproxyfen immediately after blood feeding. There was no mortality in eggs laid by females that survived larval and pupal exposures. In conclusion, diapausing eggs were the more susceptible to pyriproxyfen diapause termination compared to other life stages. This is the first report of diapause termination in A. albopictus with a juvenile hormone analog. We believe our findings will be useful in developing a new control strategy against overwintering mosquito populations. PMID:26090954

  15. 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

  16. The Insect Growth Regulator Pyriproxyfen Terminates Egg Diapause in the Asian Tiger Mosquito, Aedes albopictus.

    Directory of Open Access Journals (Sweden)

    Devi S Suman

    Full Text Available The Asian tiger mosquito, Aedes albopictus, is a highly invasive mosquito species that transmits chikungunya and dengue. This species overwinters as diapausing eggs in temperate climates. Early diapause termination may be a beneficial strategy for winter mosquito control; however, a mechanism to terminate the diapause process using chemicals is not known. We tested the hypothesis that a hormonal imbalance caused by the administration of juvenile hormone analog would terminate egg diapause in A. albopictus. We tested the insect growth regulator pyriproxyfen on all developmental stages to identify a susceptible stage for diapause termination. We found that pyriproxyfen treatment of mosquito eggs terminated embryonic diapause. The highest rates of diapause termination were recorded in newly deposited (78.9% and fully embryonated (74.7% eggs at 0.1 and 1 ppm, respectively. Hatching was completed earlier in newly deposited eggs (25-30 days compared to fully embryonated eggs (71-80 days. The combined mortality from premature diapause termination and ovicidal activity was 98.2% in newly deposited and >98.9% in fully embryonated eggs at 1 ppm. The control diapause eggs did not hatch under diapausing conditions. Pyriproxyfen exposure to larvae, pupae and adults did not prevent the females from ovipositing diapausing eggs. There was no effect of pyriproxyfen on diapausing egg embryonic developmental time. We also observed mortality in diapausing eggs laid by females exposed to pyriproxyfen immediately after blood feeding. There was no mortality in eggs laid by females that survived larval and pupal exposures. In conclusion, diapausing eggs were the more susceptible to pyriproxyfen diapause termination compared to other life stages. This is the first report of diapause termination in A. albopictus with a juvenile hormone analog. We believe our findings will be useful in developing a new control strategy against overwintering mosquito populations.

  17. Dengue virus type 2: replication and tropisms in orally infected Aedes aegypti mosquitoes

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    Olson Ken E

    2007-01-01

    Full Text Available Abstract Background To be transmitted by its mosquito vector, dengue virus (DENV must infect midgut epithelial cells, replicate and disseminate into the hemocoel, and finally infect the salivary glands, which is essential for transmission. The extrinsic incubation period (EIP is very relevant epidemiologically and is the time required from the ingestion of virus until it can be transmitted to the next vertebrate host. The EIP is conditioned by the kinetics and tropisms of virus replication in its vector. Here we document the virogenesis of DENV-2 in newly-colonized Aedes aegypti mosquitoes from Chetumal, Mexico in order to understand better the effect of vector-virus interactions on dengue transmission. Results After ingestion of DENV-2, midgut infections in Chetumal mosquitoes were characterized by a peak in virus titers between 7 and 10 days post-infection (dpi. The amount of viral antigen and viral titers in the midgut then declined, but viral RNA levels remained stable. The presence of DENV-2 antigen in the trachea was positively correlated with virus dissemination from the midgut. DENV-2 antigen was found in salivary gland tissue in more than a third of mosquitoes at 4 dpi. Unlike in the midgut, the amount of viral antigen (as well as the percent of infected salivary glands increased with time. DENV-2 antigen also accumulated and increased in neural tissue throughout the EIP. DENV-2 antigen was detected in multiple tissues of the vector, but unlike some other arboviruses, was not detected in muscle. Conclusion Our results suggest that the EIP of DENV-2 in its vector may be shorter that the previously reported and that the tracheal system may facilitate DENV-2 dissemination from the midgut. Mosquito organs (e.g. midgut, neural tissue, and salivary glands differed in their response to DENV-2 infection.

  18. Mosquito density forecast from flooding: population dynamics model for Aedes caspius (Pallas).

    Science.gov (United States)

    Balenghien, T; Carron, A; Sinègre, G; Bicout, D J

    2010-06-01

    Insect population dynamics depend strongly on environmental factors. For floodwater mosquitoes, meteorological conditions are crucial in the rhythm of mosquito abundances. Indeed, rainfall triggers the egg hatching after flooding breeding sites, and temperature controls the duration of the aquatic immature development up to adult emergence. According to this, we have developed a simple mechanistic and tractable model that describes the population dynamics of floodwater mosquitoes as a function only of the most accessible meteorological variables, rainfall and temperature. The model involves three parameters: development duration tdev of the immature aquatic stages, the adult emergence rate function f(t) (characterized by the emergence time scale tau and shaping the profile of adult population abundance), and the depletion rate, alpha, of adult disappearance. The developed model was subsequently applied to fit experimental field data of the dynamics of Aedes caspius (Pallas), the main pest mosquito in southern France. First, it was found that the emergence rate function of adult mosquitoes very well reproduce experimental data of the dynamics of immature development for all sampled temperatures. The estimated values of tdev and tau both exhibit Arrhenius behaviour as a function of temperature. Second, using the meteorological records of rainfall and temperature as inputs, the model correctly fit data from a two-site CO2 trapping survey conducted in 2004 and 2005. The estimated depletion rates (summation of the mortality and the emigration rates) were found to be a concave quadratic function of temperature with a maximum of 0.5 per days at about 22 degrees C. PMID:20170592

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

    Directory of Open Access Journals (Sweden)

    Suzane Alves dos Santos

    2014-12-01

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

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

    OpenAIRE

    K. Vijayakumar; T. K. Sudheesh Kumar; Zinia T Nujum; Farook Umarul; Anu Kuriakose

    2014-01-01

    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 ...

  1. Identification and genetic characterization of chikungunya virus from Aedes mosquito vector collected in the Lucknow district, North India.

    Science.gov (United States)

    Nyari, N; Maan, H S; Sharma, S; Pandey, S N; Dhole, T N

    2016-06-01

    Chikungunya fever is an emerging mosquito-borne disease caused by the infection with chikungunya virus (CHIKV). The CHIKV has been rarely detected in mosquito vectors from Northern India, since vector surveillance is an effective strategy in controlling and preventing CHIKV transmission. Thus, virological investigation for CHIKV among mosquitoes of Aedes (A.) species was carried out in the Lucknow district during March 2010 to October 2011. We collected adult mosquitoes from areas with CHIKV positive patients. The adult Aedes mosquito samples were pooled, homogenized, clarified and tested for CHIKV by nonstructural protein 1 (nsP1) gene based polymerase chain reaction (PCR). A total 91 mosquito pools comprising of adult A. aegypti and A. albopictus were tested for CHIKV. The partial envelope protein (E1) gene sequences of mosquito-borne CHIKV strains were analyzed for genotyping. Of 91 pools, 6 pools of A. aegypti; and 2 pools of A. albopictus mosquitoes were identified positive for CHIKV by PCR. The phylogenetic analysis revealed clustering of CHIKV strains in two sub-lineages within the monophyletic East-Central South African (ECSA) genotype. Novel amino acid changes at the positions 294 (P294L) and 295 (S295F) were observed during analysis of amino acid sequence of the partial E1 gene. This study demonstrates the genetic diversity of circulating CHIKV strains and reports the first detection of CHIKV strains in Aedes vector species from the state of Uttar Pradesh. These findings have implication for vector control strategies to mitigate vector population to prevent the likelihood of CHIKV epidemic in the near future. PMID:26943997

  2. The Identification of Suberosin from Prangos pabularia Essential Oil and Its Mosquito Activity against Aedes aegypti

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    Nurhayat Tabanca

    2015-10-01

    Full Text Available A detailed analysis of Prangos pabularia Lindl. (Apiaceae fruit oil was performed by gas chromatography (GC-FID and gas chromatography-mass spectrometry (GC-MS. Bicyclogermacrene (21%, (Z- b -ocimene (19%, a -humulene (8%, a -pinene (8% and spathulenol (6% were the main constituents of the oil. One compound with 1.8% at RI 3420 remained unidentified or tentatively identified as suberosin from the Wiley GC-MS Library. T he assumed compound, suberosin was synthesized in two steps and its structure was confirmed by 1D NMR and GC- MS analyses. As part of our continued research to discover new chemicals for use in mosquito control agents as repellents and larvicides, suberosin and its parent compound coumarin were investigated for the mosquito biting deterrent and larvicidal activity against Aedes aegypti. Both suberosin and coumarin showed biting deterrent activity but the activity was lower than the positive control, DEET (N,N-diethyl-3-methylbenzamide. In larval bioassays, suberosin with LC 50 value of 8.1 ppm was significantly more toxic than c oumarin (LC 50 = 49.6 ppm at 24-h post treatment. These results indicate that suberosin may be useful for use as mosquito larvicidal agent .

  3. 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.

  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. First report of behavioural lateralisation in mosquitoes: right-biased kicking behaviour against males in females of the Asian tiger mosquito, Aedes albopictus.

    Science.gov (United States)

    Benelli, Giovanni; Romano, Donato; Messing, Russell H; Canale, Angelo

    2015-04-01

    Lateralisation (i.e. functional and/or structural specialisations of left and right sides of the brain) of aggressive traits has been studied in a number of vertebrates, while evidence for invertebrates is scarce. Mosquito females display aggressive responses against undesired males, performing rejection kicks with the hind legs. In this research, we examined lateralisation of kicking behaviour in females of the Asian tiger mosquito, Aedes albopictus. We found a right-biased population-level lateralisation of kicking behaviour. Four repeated testing phases on mosquito females confirmed the preferential use of right legs. However, when left legs were used, the mean number of kicks per rejection event was not different to that performed with right legs. Both left and right kicking behaviour lead to successful displacement of undesired partners. This is the first report about behavioural lateralisation in mosquitoes. PMID:25648446

  6. Inhibition of luciferase expression in transgenic Aedes aegypti mosquitoes by Sindbis virus expression of antisense luciferase RNA.

    Science.gov (United States)

    Johnson, B W; Olson, K E; Allen-Miura, T; Rayms-Keller, A; Carlson, J O; Coates, C J; Jasinskiene, N; James, A A; Beaty, B J; Higgs, S

    1999-11-01

    A rapid and reproducible method of inhibiting the expression of specific genes in mosquitoes should further our understanding of gene function and may lead to the identification of mosquito genes that determine vector competence or are involved in pathogen transmission. We hypothesized that the virus expression system based on the mosquito-borne Alphavirus, Sindbis (Togaviridae), may efficiently transcribe effector RNAs that inhibit expression of a targeted mosquito gene. To test this hypothesis, germ-line-transformed Aedes aegypti that express luciferase (LUC) from the mosquito Apyrase promoter were intrathoracically inoculated with a double subgenomic Sindbis (dsSIN) virus TE/3'2J/anti-luc (Anti-luc) that transcribes RNA complementary to the 5' end of the LUC mRNA. LUC activity was monitored in mosquitoes infected with either Anti-luc or control dsSIN viruses expressing unrelated antisense RNAs. Mosquitoes infected with Anti-luc virus exhibited 90% reduction in LUC compared with uninfected and control dsSIN-infected mosquitoes at 5 and 9 days postinoculation. We demonstrate that a gene expressed from the mosquito genome can be inhibited by using an antisense strategy. The dsSIN antisense RNA expression system is an important tool for studying gene function in vivo. PMID:10557332

  7. An integrated linkage, chromosome, and genome map for the yellow fever mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    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

  8. Distribution and habitat characterization of the recently introduced invasive mosquito Aedes koreicus [Hulecoeteomyia koreica], a new potential vector and pest in north-eastern Italy

    OpenAIRE

    Montarsi, Fabrizio; Martini, Simone; Dal Pont, Marco; Delai, Nicola; Ferro Milone, Nicola; Mazzucato, Matteo; Soppelsa, Fabio; Cazzola, Luigi; Cazzin, Stefania; Ravagnan, Silvia; Ciocchetta, Silvia; Russo, Francesca; Capelli, Gioia

    2013-01-01

    Background The container breeding species belonging to the genus Aedes (Meigen) are frequently recorded out of their place of origin. Invasive Aedes species are proven or potential vectors of important Arboviruses and their establishment in new areas pose a threat for human and animal health. A new species of exotic mosquito was recorded in 2011 in north-eastern Italy: Aedes (Finlaya) koreicus [Hulecoeteomyia koreica]. The aim of this study was to characterize the biology, the environment and...

  9. 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

  10. Dose-dependent behavioral response of the mosquito Aedes albopictus to floral odorous compounds.

    Science.gov (United States)

    Hao, Huiling; Sun, Jingcheng; Dai, Jianqing

    2013-01-01

    The value of using plant volatiles as attractants for trapping and spatial repellents to protect hosts against mosquitoes has been widely recognized. The current study characterized behavioral responses of Aedes albopictus (Skuse) (Diptera: Culicidae) to different concentrations, ranging from 6 to 96%, of several common floral odorous compounds, including linalool, geraniol, citronellal, eugenol, anisaldehyde, and citral, using a wind tunnel olfactometer system. The results indicated that female mosquitoes reacted differently to different concentrations of the tested compounds, and the reactions also were different when those chemicals were tested alone or in the presence of human host odor. When tested alone, anisaldehyde was attractive at all tested concentrations, eugenol was attractive only at concentrations of 48-96%, while citronellal, linalool, citral, and geraniol were attractive at lower concentrations and repellent at higher concentrations. When tested in the presence of a human host, all compounds except for anisaldehyde at all tested concentrations showed host-seeking inhibition to certain degrees. Based on the results, it was concluded that anisaldehyde was effective in attracting Ae. albopictus when used alone but could also remarkably inhibit the host-seeking ability at a concentration of 96%, while citral, geraniol, linalool, citronellal, and eugenol are suitable as spatial repellents. PMID:24779928

  11. Effects on male fitness of removing Wolbachia infections from the mosquito Aedes albopictus.

    Science.gov (United States)

    Calvitti, M; Moretti, R; Porretta, D; Bellini, R; Urbanelli, S

    2009-06-01

    Cytoplasmic incompatibility (CI) induced by maternally inherited Wolbachia bacteria is a potential tool for the suppression of insect pest species with appropriate patterns of infection. The Asian tiger mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) is known to be infected by two strains of Wolbachia pipientis Hertig (Rickettsiales: Rickettsiaceae), wAlb A and wAlb B, throughout its geographical distribution. This infection pattern theoretically restricts the application of CI-based control strategies. However, Wolbachia can be horizontally transferred using embryonic microinjection to generate incompatible transfected lines harbouring a single new strain of Wolbachia. In order to assess the feasibility of this approach, the effects of Wolbachia removal on mosquito fitness need to be clearly evaluated as the removal of natural superinfection is an inescapable step of this approach. Previous research has shown that uninfected females, produced by antibiotic treatment, showed a decrease in fitness compared with those infected with Wolbachia. In this study, the effect of Wolbachia removal on male fitness was investigated. Longevity and reproductive potential (mating competitiveness and sperm capacity) were assessed in both laboratory cages and greenhouses. No differences were observed between uninfected and infected males with respect to longevity, mating rate, sperm capacity and mating competitiveness in either laboratory conditions or greenhouses. The preservation of fitness in males of Ae. albopictus deprived of natural Wolbachia infection is discussed in relation to the development of incompatible insect technique suppression strategies. Finally, the potential application of aposymbiotic males in mark-release-recapture studies is suggested. PMID:19292821

  12. Ecdysis triggering hormone signaling in the yellow fever mosquito Aedes aegypti.

    Science.gov (United States)

    Dai, Li; Adams, Michael E

    2009-05-15

    At the end of each developmental stage, the yellow fever mosquito Aedes aegypti performs the ecdysis behavioral sequence, a precisely timed series of behaviors that culminates in shedding of the old exoskeleton. Here we describe ecdysis triggering hormone-immunoreactive Inka cells located at branch points of major tracheal trunks and loss of staining coincident with ecdysis. Peptides (AeaETH1, AeaETH2) purified from extracts of pharate 4th instar larvae have--PRXamide C-terminal amino acid sequence motifs similar to ETHs previously identified in moths and flies. Injection of synthetic AeaETHs induced premature ecdysis behavior in pharate larvae, pupae and adults. Two functionally distinct subtypes of ETH receptors (AeaETHR-A, AeaETHR-B) of A. aegypti are identified and show high sensitivity and selectivity to ETHs. Increased ETHR transcript levels and behavioral sensitivity to AeaETHs arising in the hours preceding the 4th instar larva-to-pupa ecdysis are correlated with rising ecdysteroid levels, suggesting steroid regulation of receptor gene expression. Our description of natural and ETH-induced ecdysis in A. aegypti should facilitate future approaches directed toward hormone-based interference strategies for control of mosquitoes as human disease vectors. PMID:19298818

  13. Effect of mosquito midgut trypsin activity on dengue-2 virus infection and dissemination in Aedes aegypti.

    Science.gov (United States)

    Molina-Cruz, Alvaro; Gupta, Lalita; Richardson, Jason; Bennett, Kristine; Black, William; Barillas-Mury, Carolina

    2005-05-01

    The effect of mosquito midgut trypsins in dengue serotype 2 flavivirus (DENV-2) infectivity to Aedes aegypti was studied. Addition of soybean trypsin inhibitor (STI) in a DENV-2 infectious blood meal resulted in a 91-97% decrease in midgut DENV-2 RNA copies (qRT-PCR analysis). STI treatment also resulted in slower DENV-2 replication in the midgut, less DENV-2 E protein expression, and decreased dissemination to the thorax and the head. A second uninfected blood meal, 7 days after the STI-treated infectious meal, significantly increased DENV-2 replication in the midgut and recovered oogenesis, suggesting that the lower viral infection caused by STI was in part due to a nutritional effect. Mosquitoes fed DENV-2 digested in vitro with bovine trypsin (before STI addition) exhibited a transient increase in midgut DENV-2 4 days postinfection. Blood digestion and possibly DENV-2 proteolytic processing, mediated by midgut trypsins, influence the rate of DENV-2 infection, replication, and dissemination in Ae. aegypti. PMID:15891140

  14. 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

  15. First isolation of Aedes flavivirus in the Western Hemisphere and evidence of vertical transmission in the mosquito Aedes (Stegomyia) albopictus (Diptera: Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Haddow, Andrew D., E-mail: adhaddow@gmail.com [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Guzman, Hilda; Popov, Vsevolod L. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Wood, Thomas G.; Widen, Steven G. [Department of Biochemistry and Molecular Biology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States); Haddow, Alastair D. [Mercy Clinic, 2115 S. Fremont, Springfield, MO 65804 (United States); Tesh, Robert B.; Weaver, Scott C. [Institute for Human Infections and Immunity, Center for Emerging Infectious Diseases and Biodefense, Department of Pathology, University of Texas Medical Branch, Galveston, TX 77555-0609 (United States)

    2013-06-05

    We report here the first evidence of vertical transmission of Aedes flavivirus (AEFV) and its first isolation in the Western Hemisphere. AEFV strain SPFLD-MO-2011-MP6 was isolated in C6/36 cells from a pool of male Aedes albopictus mosquitoes that were reared to adults from larvae collected in southwest Missouri, USA, in 2011. Electron micrographs of the virus showed virions of approximately 45 nm in diameter with morphological characteristics associated with flaviviruses. The genomic sequence demonstrated that AEFV-SPFLD-MO-2011-MP6 shares a high degree of nucleotide and amino acid sequence identity with the AEFV Narita-21 strain, isolated in Japan in 2003. Intracerebral inoculation of newborn mice with the virus failed to produce observable illness or death and the virus did not replicate in vertebrate cells, consistent with a lack of vertebrate host range. - Highlights: ► The first report of Aedes flavivirus (AEFV) in the Western Hemisphere. ► The first evidence of vertical transmission of AEFV in mosquitoes. ► The first electron micrograph of AEFV. ► The first attempt to infect animals with AEFV.

  16. Odonate Nymphs: Generalist Predators and their Potential in the Management of Dengue Mosquito, Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Waseem Akram

    2016-01-01

    Full Text Available Background: Dengue is amongst the most serious mosquito-borne infectious disease with hot spots in tropical and subtropical parts of the world. Unfortunately, no licensed vaccine for the disease is currently available in medicine markets. The only option available is the management of dengue vector mosquito, Aedes aegypti (Diptera: Culicidae.Method: Predatory potential of five odonate nymphs namely Anax parthenope, Bradinopyga geminate, Ischnura forcipata, Rhinocypha quadrimaculata, and Orthetrum sabina were evaluated against the 4th instar larvae of the den­gue vector mosquito, Aedes aegypti, under laboratory conditions. The consumption of the mosquito larvae was eval­uated at three water volume levels viz., 1 liter, 2 liter and 3 liter.Results: The number of Ae. aegypti larvae consumed varied significantly among the five species, and at different levels of water volume (P< 0.01. However, the interaction between odonate nymphs and the water volumes was statistically non-significant (P> 0.05. Ischnura forcipata consumed the highest number of Ae. aegypti larvae (n=56 followed by A. parthenope (n=47 and B. geminate (n=46. The number of larvae consumed was decreased with in­creasing search area or water volume, and the highest predation was observed at 1-liter water volume.Conclusion: The odonate nymphs could be a good source of biological agents for the management of the mosquitoes at larval stages. 

  17. 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.

  18. 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.

  19. Leucokinin mimetic elicits aversive behavior in mosquito Aedes aegypti (L.) and inhibits the sugar taste neuron.

    Science.gov (United States)

    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

  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. 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.

  2. A spatial model with pulsed releases to compare strategies for the sterile insect technique applied to the mosquito Aedes aegypti

    OpenAIRE

    Evans, T. P. O.; Bishop, S.R.

    2014-01-01

    We present a simple mathematical model to replicate the key features of the sterile insect technique (SIT) for controlling pest species, with particular reference to the mosquito Aedes aegypti, the main vector of dengue fever. The model differs from the majority of those studied previously in that it is simultaneously spatially explicit and involves pulsed, rather than continuous, sterile insect releases. The spatially uniform equilibria of the model are identified and analysed. Simulations a...

  3. 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...

  4. Retrospective search for dengue vector mosquito Aedes albopictus in areas visited by a German traveler who contracted dengue in Japan

    OpenAIRE

    Mutsuo Kobayashi; Osamu Komagata; Mayuko Yonejima; Yoshihide Maekawa; Kimio Hirabayashi; Toshihiko Hayashi; Naoko Nihei; Masahiro Yoshida; Yoshio Tsuda; Kyoko Sawabe

    2014-01-01

    A German traveler developed dengue fever in late August 2013, following a direct flight from Germany. Autochthonous dengue virus (DENV) infection has not been reported in Japan. To evaluate the risk of autochthonous DENV transmission in Japan, the authors performed a retrospective search of the five areas visited by the German patient to determine the population density of dengue vector mosquito, Aedes albopictus. The annual mean temperature of each area was higher than 12 °C, which is consid...

  5. Ovicidal and Oviposition Deterrent Activities of Medicinal Plant Extracts Against Aedes aegypti L. and Culex quinquefasciatus Say Mosquitoes (Diptera: Culicidae)

    OpenAIRE

    Reegan, Appadurai Daniel; Gandhi, Munusamy Rajiv; Paulraj, Micheal Gabriel; Ignacimuthu, Savarimuthu

    2014-01-01

    Objectives To evaluate the ovicidal and oviposition deterrent activities of five medicinal plant extracts namely Aegle marmelos (Linn.), Limonia acidissima (Linn.), Sphaeranthus indicus (Linn.), Sphaeranthus amaranthoides (burm.f), and Chromolaena odorata (Linn.) against Culex quinquefasciatus and Aedes aegypti mosquitoes. Three solvents, namely hexane, ethyl acetate, and methanol, were used for the preparation of extracts from each plant. Methods Four different concentrations—62.5 parts per ...

  6. Surveillance of Aedes aegypti (L. Mosquitoes in Mumbai International Seaport (India to Monitor Potential Global Health Risks

    Directory of Open Access Journals (Sweden)

    Kaushal Kumar

    2014-01-01

    Full Text Available Aedes mosquitoes are highly invasive and can survive almost any climatic conditions. They transmit a number of major world's deadly diseases. Therefore, a study was undertaken during December 2010 to evaluate the entomo-epidemiological risk of Aedes mosquito borne diseases (VBD in Mumbai international seaport areas to minimize potential global health risks and prevent introduction of new VBD in India. Surveys were undertaken in operational and residential areas of Mumbai Port Trust (MPT. All the entomological indices were found to be above the critical level, prescribed for seaports by International Health Regulations Act, 2005. The operational areas where large goods are handled from cargo ships were found to be more prone to mosquito breeding comparing to residential areas. High insecticide tolerance of Aedes aegypti population against temephos and fenthion from Mumbai port area is reported for the first time. A careful and regular invigilation of the international seaports to prevent building up of vector density of dengue/chikungunya and yellow fever is recommended.

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

    Science.gov (United States)

    Pérez-Castro, Rosalía; Castellanos, Jaime E; Olano, Víctor A; Matiz, María Inés; Jaramillo, Juan F; Vargas, Sandra L; Sarmiento, Diana M; Stenström, Thor Axel; Overgaard, Hans J

    2016-01-01

    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. PMID:27074252

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Bacterial Community Structure in Tree Hole Habitats of Ochlerotatus Triseriatus: Influences of Larval Feeding

    OpenAIRE

    Xu, Y.; Chen, S.; Kaufman, M. G.; Maknojia, S.; Bagdasarian, M; WALKER, E. D.

    2008-01-01

    We investigated the bacterial community composition of tree holes in relation to the presence and absence of larvae of the mosquito Ochlerotatus triseriatus. Larvae were eliminated from a subset of natural tree holes with Bacillus thuringiensis serovar israelensis, and total bacterial numbers, slow- and fast-growing colony-forming units on minimal media, and 16S rRNA gene sequence data from water column and leaf material were obtained. Total bacterial counts did not change significantly with ...

  10. 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 ...

  11. 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

  12. 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.

  13. Mosquito-Producing Containers, Spatial Distribution, and Relationship between Aedes aegypti Population Indices on the Southern Boundary of its Distribution in South America (Salto, Uruguay)

    Science.gov (United States)

    Basso, César; Caffera, Ruben M.; García da Rosa, Elsa; Lairihoy, Rosario; González, Cristina; Norbis, Walter; Roche, Ingrid

    2012-01-01

    A study was conducted in the city of Salto, Uruguay, to identify mosquito-producing containers, the spatial distribution of mosquitoes and the relationship between the different population indices of Aedes aegypti. On each of 312 premises visited, water-filled containers and immature Ae. aegypti mosquitoes were identified. The containers were counted and classified into six categories. Pupae per person and Stegomyia indices were calculated. Pupae per person were represented spatially. The number of each type of container and number of mosquitoes in each were analyzed and compared, and their spatial distribution was analyzed. No significant differences in the number of the different types of containers with mosquitoes or in the number of mosquitoes in each were found. The distribution of the containers with mosquito was random and the distribution of mosquitoes by type of container was aggregated or highly aggregated. PMID:23128295

  14. 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

  15. First report in italy of the exotic mosquito species Aedes (Finlaya koreicus, a potential vector of arboviruses and filariae

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    Capelli Gioia

    2011-09-01

    Full Text Available Abstract Background In the Veneto region (north-eastern Italy an entomological surveillance system has been implemented since the introduction of the Asian tiger mosquito (Aedes albopictus in 1991. During the routine monitoring activity in a tiger mosquito-free area, an unexpected mosquito was noticed, which clearly did not belong to the recorded Italian fauna. Findings At the end of May 2011, twelve larvae and pupae were collected in a small village in Belluno province (Veneto region from a single manhole. Ten adults reared in the laboratory were morphologically and genetically identified as Aedes (Finlaya koreicus (Edwards, 1917, a species native to Southeast Asia. The subsequent investigations carried out in the following months in the same village provided evidence that this species had become established locally. Entomological and epidemiological investigations are currently ongoing in the surrounding area, to verify the eventual extension of the species outside the village and to trace back the route of entry into Italy. Conclusions This is the first report in Italy of the introduction of the exotic mosquito Ae. koreicus. This species has been shown experimentally to be competent in the transmission of the Japanese encephalitis virus and of the dog heartworm Dirofilaria immitis and is considered a potential vector of other arboviruses. Thus, the establishment of this species may increase the current risk or pose new potential threats, for human and animal health. This finding considerably complicates the entomological monitoring of the Asian tiger mosquito Ae. albopictus in Italy and stresses the importance of implementing the entomological surveillance for the early detection of and the rapid response against invasive mosquito species.

  16. Proteomic profiling of a robust Wolbachia infection in an Aedes albopictus mosquito cell line.

    Science.gov (United States)

    Baldridge, Gerald D; Baldridge, Abigail S; Witthuhn, Bruce A; Higgins, LeeAnn; Markowski, Todd W; Fallon, Ann M

    2014-11-01

    Wolbachia pipientis, a widespread vertically transmitted intracellular bacterium, provides a tool for insect control through manipulation of host-microbe interactions. We report proteomic characterization of wStr, a Wolbachia strain associated with a strong cytoplasmic incompatibility phenotype in its native host, Laodelphax striatellus. In the Aedes albopictus C/wStr1 mosquito cell line, wStr maintains a robust, persistent infection. MS/MS analyses of gel bands revealed a protein 'footprint' dominated by Wolbachia-encoded chaperones, stress response and cell membrane proteins, including the surface antigen WspA, a peptidoglycan-associated lipoprotein and a 73 kDa outer membrane protein. Functional classifications and estimated abundance levels of 790 identified proteins suggested that expression, stabilization and secretion of proteins predominate over bacterial genome replication and cell division. High relative abundances of cysteine desulphurase, serine/glycine hydroxymethyl transferase, and components of the α-ketoglutarate dehydrogenase complex in conjunction with above average abundances of glutamate dehydrogenase and proline utilization protein A support Wolbachia genome-based predictions for amino acid metabolism as a primary energy source. wStr expresses 15 Vir proteins of a Type IV secretion system and its transcriptional regulator. Proteomic characterization of a robust insect-associated Wolbachia strain provides baseline information that will inform further development of in vitro protocols for Wolbachia manipulation. PMID:25155417

  17. Population genetics of the Asian tiger mosquito Aedes albopictus, an invasive vector of human diseases.

    Science.gov (United States)

    Goubert, C; Minard, G; Vieira, C; Boulesteix, M

    2016-09-01

    The Asian tiger mosquito Aedes albopictus is currently one of the most threatening invasive species in the world. Native to Southeast Asia, the species has spread throughout the world in the past 30 years and is now present in every continent but Antarctica. Because it was the main vector of recent Dengue and Chikungunya outbreaks, and because of its competency for numerous other viruses and pathogens such as the Zika virus, A. albopictus stands out as a model species for invasive diseases vector studies. A synthesis of the current knowledge about the genetic diversity of A. albopictus is needed, knowing the interplays between the vector, the pathogens, the environment and their epidemiological consequences. Such resources are also valuable for assessing the role of genetic diversity in the invasive success. We review here the large but sometimes dispersed literature about the population genetics of A. albopictus. We first debate about the experimental design of these studies and present an up-to-date assessment of the available molecular markers. We then summarize the main genetic characteristics of natural populations and synthesize the available data regarding the worldwide structuring of the vector. Finally, we pinpoint the gaps that remain to be addressed and suggest possible research directions. PMID:27273325

  18. Genome Engineering with CRISPR-Cas9 in the Mosquito Aedes aegypti

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    Kathryn E. Kistler

    2015-04-01

    Full Text Available 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. This system relies on RNA-DNA base-pairing to generate targeting specificity, resulting in efficient and flexible genome-editing reagents. We investigate the efficiency of injection mix compositions, demonstrate the ability of CRISPR-Cas9 to generate different types of mutations via disparate repair mechanisms, and report stable germline mutations in several genomic loci. This work offers a detailed exploration into the use of CRISPR-Cas9 in Ae. aegypti that should be applicable to non-model organisms previously out of reach of genetic modification.

  19. The molecular physiology of increased egg desiccation resistance during diapause in the invasive mosquito, Aedes albopictus

    Science.gov (United States)

    Urbanski, Jennifer M.; Benoit, Joshua B.; Michaud, M. Robert; Denlinger, David L.; Armbruster, Peter

    2010-01-01

    Photoperiodic diapause is a crucial adaptation to seasonal environmental variation in a wide range of arthropods, but relatively little is known regarding the molecular basis of this important trait. In temperate populations of the mosquito Aedes albopictus, exposure to short-day (SD) lengths causes the female to produce diapause eggs. Tropical populations do not undergo a photoperiodic diapause. We identified a fatty acyl coA elongase transcript that is more abundant under SD versus long-day (LD) photoperiods in mature oocyte tissue of replicate temperate, but not tropical, A. albopictus populations. Fatty acyl CoA elongases are involved in the synthesis of long chain fatty acids (hydrocarbon precursors). Diapause eggs from a temperate population had one-third more surface hydrocarbons and one-half the water loss rates of non-diapause eggs. Eggs from a tropical population reared under SD and LD photoperiods did not differ in surface hydrocarbon abundance or water loss rates. In both a temperate and tropical population, composition of hydrocarbon chain lengths did not differ between eggs from SD versus LD conditions. These results implicate the expression of fatty acyl coA elongase and changes in quantity, but not composition, of egg surface hydrocarbons as important components of increased desiccation resistance during diapause in A. albopictus. PMID:20410035

  20. 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.

  1. 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

  2. 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.

  3. Effect of Polygonum hydropiper L. against dengue vector mosquito Aedes albopictus L.

    Science.gov (United States)

    Maheswaran, Rajan; Ignacimuthu, Savarimuthu

    2014-09-01

    The present study aimed to evaluate the essential oil and an isolated compound from the leaves of Polygonum hydropiper L. against dengue vector mosquito Aedes albopictus L. The plant material was macerated and steam distilled using clavenger apparatus for oil extraction. The essential oil was tested at different concentrations of 100, 50, 25, 12.5 and 6.25 ppm concentrations against the larvae of Ae. albopictus. The isolated compound was tested for larvicidal, ovicidal, repellent, oviposition deterrent and adulticidal activities at 10, 5, 2.5, 1.25 and 0.625 ppm concentrations. The essential oil exhibited LC₅₀ values of 194.63 and 199.65 and confertifolin exhibited LC₅₀ values of 2.02 and 3.16 against the second and fourth instar larvae of Ae. albopictus, respectively. The ovicidal activity of 100% on 0- to 6-h-old eggs, repellent activity of 320.6 min, oviposition deterrent activity of 98.51% and adulticidal activity of 100% at 10 ppm concentration of confertifolin were recorded. No mortality of was observed in negative control. To the best of our knowledge, this is the first report on the potential mosquitocidal activities of confertifolin against Ae. albopictus. PMID:25033815

  4. 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.

  5. Spatial genetic structure of Aedes aegypti mosquitoes in mainland Southeast Asia.

    Science.gov (United States)

    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

  6. From lab to field: the influence of urban landscapes on the invasive potential of Wolbachia in Brazilian Aedes aegypti mosquitoes.

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    Heverton Leandro Carneiro Dutra

    2015-04-01

    Full Text Available The symbiotic bacterium Wolbachia is currently being trialled as a biocontrol agent in several countries to reduce dengue transmission. Wolbachia can invade and spread to infect all individuals within wild mosquito populations, but requires a high rate of maternal transmission, strong cytoplasmic incompatibility and low fitness costs in the host in order to do so. Additionally, extensive differences in climate, field-release protocols, urbanization level and human density amongst the sites where this bacterium has been deployed have limited comparison and analysis of Wolbachia's invasive potential.We examined key phenotypic effects of the wMel Wolbachia strain in laboratory Aedes aegypti mosquitoes with a Brazilian genetic background to characterize its invasive potential. We show that the wMel strain causes strong cytoplasmic incompatibility, a high rate of maternal transmission and has no evident detrimental effect on host fecundity or fertility. Next, to understand the effects of different urban landscapes on the likelihood of mosquito survival, we performed mark-release-recapture experiments using Wolbachia-uninfected Brazilian mosquitoes in two areas of Rio de Janeiro where Wolbachia will be deployed in the future. We characterized the mosquito populations in relation to the socio-demographic conditions at these sites, and at three other future release areas. We then constructed mathematical models using both the laboratory and field data, and used these to describe the influence of urban environmental conditions on the likelihood that the Wolbachia infection frequency could reach 100% following mosquito release. We predict successful invasion at all five field sites, however the conditions by which this occurs vary greatly between sites, and are strongly influenced by the size of the local mosquito population.Through analysis of laboratory, field and mathematical data, we show that the wMel strain of Wolbachia possesses the characteristics

  7. Repellent and mosquitocidal effects of leaf extracts of Clausena anisata against the Aedes aegypti mosquito (Diptera: Culicidae).

    Science.gov (United States)

    Mukandiwa, Lillian; Eloff, Jacobus Nicolaas; Naidoo, Vinny

    2016-06-01

    Mosquitoes are rapidly developing resistance to insecticides that millions of people relied on to protect themselves from the diseases they carry, thereby creating a need to develop new insecticides. Clausena anisata is used traditionally as an insect repellent by various communities in Africa and Asia. For this study, the repellency and adulticidal activities of leaf extracts and compounds isolated from this plant species were evaluated against the yellow fever mosquito, Aedes aegypti. In the topical application assays, using total bites as an indicator, repellency was dose dependent, with the acetone crude extract (15 %) having 93 % repellence and the hexane fraction (7.5 %) 67 % repellence after 3 h. Fractionation resulted in a loss of total repellence. As mosquito-net treating agents, the acetone and hexane extracts of C. anisata, both at 15 %, had average repellences of 46.89 ± 2.95 and 50.13 ± 2.02 %, respectively, 3 h after exposure. The C. anisata acetone extract and its hexane fraction caused mosquito knockdown and eventually death when nebulised into the testing chamber, with an EC50 of 78.9 mg/ml (7.89 %) and 71.6 mg/ml (7.16 %) in the first 15 min after spraying. C. anisata leaf extracts have potential to be included in protection products against mosquitoes due to the repellent and cidal compounds contained therein. PMID:26924698

  8. Mosquito larvicidal properties of volatile oil from salt marsh mangrove plant of Sesuvium portulacastrum against Anopheles stephensi and Aedes aegypti

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    Mohamed Yacoob Syed Ali

    2013-08-01

    Full Text Available Objective: To identify the larvicidal activity of the volatile oil from Sesuvium portulacastrum (S. portulacastrum against Anopheles stephensi and Aedes aegypti. Methods: Volatile oil extract of S. portulacastrum was prepared in a graded series of concentration. The test for the larvicidal effect of volatile oil against mosquitos larvae was conducted in accordance with the WHO standard method. Batches of 25 early 4th instar larvae of two mosquitoes were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts. Each experiment was conducted with triplicate with concurrent a control group. Results: Volatile oil extract of S. portulacastrum showed toxicity against 4th instar larvae of Aedes aegypti and Anopheles stephensi with equivalent LC50 value [(63±7.8 µL/mL, LCL-UCL=55.2-64.0] and LC90 value [(94.2±3.9 µL/mL] in maximum activity with minimum concentration (200 µL/mL of volatile oil and followed by maximum activity of 250 µL concentration showed LC50 value=(68.0±8.2 µL/mL, LCL-UCL=66.26-69.2 and LC50 value of (55.2±2.8 µL/mL, LCL-UCL=53.7-56.9, LC90=(95.2±1.25 µL/mL and followed by 250 µL of oil extract against 4th instar larvae of Aedes aegypti respectively. Conclusions: It is inferred from the present study that, the extracts from salt marsh mangrove plan of S. portulacastum are identified as a potential source of safe and efficacious mosquito control agents for the management of vector borne diseases of malaria and dengue.

  9. Mosquito larvicidal properties of volatile oil from salt marsh mangrove plant of Sesuvium portulacastrum against Anopheles stephensi and Aedes aegypti

    Institute of Scientific and Technical Information of China (English)

    Mohamed Yacoob Syed Ali; Venkatraman Anuradha; SyedAbudhair Sirajudeen; Prathasarathy Vijaya; Nagarajan Yogananth; Ramachandran Rajan; Peer Mohamed Kalitha Parveen

    2013-01-01

    Objective: To identify the larvicidal activity of the volatile oil from Sesuvium portulacastrum (S.portulacastrum ) against Anopheles stephensi and Aedes aegypti. Methods: Volatile oil extract of S. portulacastrum was prepared in a graded series of concentration. The test for the larvicidal effect of volatile oil against mosquitos larvae was conducted in accordance with the WHO standard method. Batches of 25 early 4th instar larvae of two mosquitoes were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts. Each experiment was conducted with triplicate with concurrent a control group.Results:Volatile oil extract of S. portulacastrum showed toxicity against 4th instar larvae of Aedes aegypti and Anopheles stephensi with equivalent LC50 value [(63±7.8) µL/mL, LCL-UCL=55.2-64.0] and LC90 value [(94.2±3.9) µL/mL)] in maximum activity with minimum concentration (200 µL/mL) of volatile oil and followed by maximum activity of 250 µL concentration showed LC50 value=(68.0±8.2) µL/mL, LCL-UCL=66.26-69.2 and LC50 value of (55.2±2.8) µL/mL, LCL-UCL=53.7-56.9, LC90=(95.2±1.25) µL/mL and followed by 250 µL of oil extract against 4th instar larvae of Aedes aegypti respectively.Conclusions:It is inferred from the present study that, the extracts from salt marsh mangrove plan of S. portulacastum are identified as a potential source of safe and efficacious mosquito control agents for the management of vector borne diseases of malaria and dengue.

  10. Pharmacological and Genetic Evidence for Gap Junctions as Potential New Insecticide Targets in the Yellow Fever Mosquito, Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Travis L Calkins

    Full Text Available The yellow fever mosquito Aedes aegypti is an important vector of viral diseases that impact global health. Insecticides are typically used to manage mosquito populations, but the evolution of insecticide resistance is limiting their effectiveness. Thus, identifying new molecular and physiological targets in mosquitoes is needed to facilitate insecticide discovery and development. Here we test the hypothesis that gap junctions are valid molecular and physiological targets for new insecticides. Gap junctions are intercellular channels that mediate direct communication between neighboring cells and consist of evolutionarily distinct proteins in vertebrate (connexins and invertebrate (innexins animals. We show that the injection of pharmacological inhibitors of gap junctions (i.e., carbenoxolone, meclofenamic acid, or mefloquine into the hemolymph of adult female mosquitoes elicits dose-dependent toxic effects, with mefloquine showing the greatest potency. In contrast, when applied topically to the cuticle, carbenoxolone was the only inhibitor to exhibit full efficacy. In vivo urine excretion assays demonstrate that both carbenoxolone and mefloquine inhibit the diuretic output of adult female mosquitoes, suggesting inhibition of excretory functions as part of their mechanism of action. When added to the rearing water of 1st instar larvae, carbenoxolone and meclofenamic acid both elicit dose-dependent toxic effects, with meclofenamic acid showing the greatest potency. Injecting a double-stranded RNA cocktail against innexins into the hemolymph of adult female mosquitoes knock down whole-animal innexin mRNA expression and decreases survival of the mosquitoes. Taken together these data indicate that gap junctions may provide novel molecular and physiological targets for the development of insecticides.

  11. Retrospective search for dengue vector mosquito Aedes albopictus in areas visited by a German traveler who contracted dengue in Japan

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    Mutsuo Kobayashi

    2014-09-01

    Full Text Available A German traveler developed dengue fever in late August 2013, following a direct flight from Germany. Autochthonous dengue virus (DENV infection has not been reported in Japan. To evaluate the risk of autochthonous DENV transmission in Japan, the authors performed a retrospective search of the five areas visited by the German patient to determine the population density of dengue vector mosquito, Aedes albopictus. The annual mean temperature of each area was higher than 12 °C, which is considered suitable for the establishment of A. albopictus populations. Our retrospective search revealed the population density of A. albopictus to be high in the urban areas of Japan.

  12. 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

  13. Assessing key safety concerns of a Wolbachia-based strategy to control dengue transmission by Aedes mosquitoes

    Directory of Open Access Journals (Sweden)

    Jean Popovici

    2010-12-01

    Full Text Available Mosquito-borne diseases such as dengue fever, chikungunya or malaria affect millions of people each year and control solutions are urgently needed. An international research program is currently being developed that relies on the introduction of the bacterial endosymbiont Wolbachia pipientis into Aedes aegypti to control dengue transmission. In order to prepare for open-field testing releases of Wolbachia-infected mosquitoes, an intensive social research and community engagement program was undertaken in Cairns, Northern Australia. The most common concern expressed by the diverse range of community members and stakeholders surveyed was the necessity of assuring the safety of the proposed approach for humans, animals and the environment. To address these concerns a series of safety experiments were undertaken. We report in this paper on the experimental data obtained, discuss the limitations of experimental risk assessment and focus on the necessity of including community concerns in scientific research.

  14. 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

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

    OpenAIRE

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

    2015-01-01

    Control of aedine mosquito vectors, either by mosquito population reduction or replacement with refractory mosquitoes, may play an essential role in the fight against arboviral diseases. In this review, we will focus on the development and application of biological approaches, both natural or engineered, to limit mosquito vector competence for arboviruses. The study of mosquito antiviral immunity has led to the identification of a number of host response mechanisms and proteins that are requi...

  16. Analysis of the wild-type and mutant genes encoding the enzyme kynurenine monooxygenase of the yellow fever mosquito, Aedes aegypti

    OpenAIRE

    Han, Q; Calvo, E.; Marinotti, O.; Fang, J; Rizzi, M; James, A A; Li, J.

    2003-01-01

    Kynurenine 3-monooxygenase (KMO) catalyses the hydroxylation of kynurenine to 3-hydroxykynurenine. KMO has a key role in tryptophan catabolism and synthesis of ommochrome pigments in mosquitoes. The gene encoding this enzyme in the yellow fever mosquito, Aedes aegypti, is called kynurenine hydroxylase (kh) and a mutant allele that produces white eyes has been designated khw. A number of cDNA clones representative of wild-type and mutant genes were isolated. Sequence analyses of the wild-type ...

  17. 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...

  18. Insecticidal and repellent activity of Clausena dentata (Rutaceae) plant extracts against Aedes aegypti and Culex quinquefasciatus mosquitoes (Diptera: Culicidae).

    Science.gov (United States)

    Ramkumar, Govindaraju; Karthi, Sengodan; Muthusamy, Ranganathan; Natarajan, Devarajan; Shivakumar, Muthugounder Subramanian

    2015-03-01

    Mosquito control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol agents. The present study is to evaluate adulticidal activity of Clausena dentata plant extract against Aedes aegypti and Culex quinquefasciatus mosquitoes. The adult mortality was observed after 24 h of exposure. The highest mortality was found in acetone extracts against Ae. aegypti and Cx. quinquefasciatus with the LC50 and LC90 4.1783 mg/ml (3.8201-7.1026), 9.3884 mg/ml (7. 8258-13.1820) and 4.2451 mg/ml (3.8547-8.0254), 12.3214 mg/ml (10.9287-16.2220), respectively. Smoke toxicity was observed at 10-min interval for 40 min, and the mortality data were recorded. Result shows that Ae. aegypti and Cx. quinquefasciatus are 85 ± 2 and 89 ± 1.5, respectively. A mortality of 100 % was recorded in the commercial mosquito control. These results suggest that the leaf extracts of C. dentata have a potential to be used as an ideal eco-friendly approach for the control of mosquitoes. PMID:25573693

  19. Optimal barrier zones for stopping the invasion of Aedes aegypti mosquitoes via transgenic or sterile insect techniques

    KAUST Repository

    Lee, S. Seirin

    2013-03-27

    Biological invasions have dramatically altered the natural world by threatening native species and their communities. Moreover, when the invading species is a vector for human disease, there are further substantive public health and economic impacts. The development of transgenic technologies is being explored in relation to new approaches for the biological control of insect pests. We investigate the use of two control strategies, classical sterile insect techniques and transgenic late-acting bisex lethality (Release of Insects carrying a Dominant Lethal), for controlling invasion of the mosquito Aedes aegypti using a spatial stage-structured mathematical model. In particular, we explore the use of a barrier zone of sterile/transgenic insects to prevent or impede the invasion of mosquitoes. We show that the level of control required is not only highly sensitive to the rate at which the sterile/transgenic males are released in the barrier zone but also to the spatial range of release. Our models characterise how the distribution of sterile/transgenic mosquitoes in the barrier zone can be controlled so as to minimise the number of mass-produced insects required for the arrest of species invasion. We predict that, given unknown rates of mosquito dispersal, management strategies should concentrate on larger release areas rather than more intense release rates for optimal control. © 2013 Springer Science+Business Media Dordrecht.

  20. Climatic factors driving invasion of the tiger mosquito (Aedes albopictus into new areas of Trentino, northern Italy.

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    David Roiz

    Full Text Available BACKGROUND: The tiger mosquito (Aedes albopictus, vector of several emerging diseases, is expanding into more northerly latitudes as well as into higher altitudes in northern Italy. Changes in the pattern of distribution of the tiger mosquito may affect the potential spread of infectious diseases transmitted by this species in Europe. Therefore, predicting suitable areas of future establishment and spread is essential for planning early prevention and control strategies. METHODOLOGY/PRINCIPAL FINDINGS: To identify the areas currently most suitable for the occurrence of the tiger mosquito in the Province of Trento, we combined field entomological observations with analyses of satellite temperature data (MODIS Land Surface Temperature: LST and human population data. We determine threshold conditions for the survival of overwintering eggs and for adult survival using both January mean temperatures and annual mean temperatures. We show that the 0°C LST threshold for January mean temperatures and the 11°C threshold for annual mean temperatures provide the best predictors for identifying the areas that could potentially support populations of this mosquito. In fact, human population density and distance to human settlements appear to be less important variables affecting mosquito distribution in this area. Finally, we evaluated the future establishment and spread of this species in relation to predicted climate warming by considering the A2 scenario for 2050 statistically downscaled at regional level in which winter and annual temperatures increase by 1.5 and 1°C, respectively. CONCLUSIONS/SIGNIFICANCE: MODIS satellite LST data are useful for accurately predicting potential areas of tiger mosquito distribution and for revealing the range limits of this species in mountainous areas, predictions which could be extended to an European scale. We show that the observed trend of increasing temperatures due to climate change could facilitate further

  1. 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.

  2. 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

  3. Pupal productivity & nutrient reserves of Aedes mosquitoes breeding in sewage drains & other habitats of Kolkata, India: Implications for habitat expansion & vector management

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    Soumyajit Banerjee

    2015-01-01

    Full Text Available Background & objectives: The quality of breeding sites is reflected through the pupal productivity and the life history traits of Aedes mosquitoes. Using nutrient reserves and pupal productivity of Aedes as indicators, the larval habitats including sewage drains were characterized to highlight the habitat expansion and vector management. Methods: The pupae and adults collected from the containers and sewage drains were characterized in terms of biomass and nutrient reserves and the data were subjected to three way factorial ANOVA. Discriminant function analyses were performed to highlight the differences among the habitats for sustenance of Aedes mosquitoes. Results: Survey of larval habitats from the study area revealed significant differences (P<0.05 in the pupal productivity of Aedes among the habitats and months. Despite sewage drains being comparatively less utilized for breeding, the pupae were of higher biomass with corresponding adults having longer wings in contrast to other habitats. The nutrient reserve of the adults emerging from pupae of sewage drains was significantly higher (P<0.05, compared to other habitats, as reflected through the discriminant function analysis. Interpretation & conclusions: The present results showed that for both Ae. aegypti and Ae. albopictus, sewage drains were equally congenial habitat as were plastic, porcelain and earthen habitats. Availability of Aedes immature in sewage drains poses increased risk of dengue, and thus vector control programme should consider inclusion of sewage drains as breeding habitat of dengue vector mosquitoes.

  4. Effects of Cohabitation on the Population Performance and Survivorship of the Invasive Mosquito Aedes albopictus and the Resident Mosquito Aedes notoscriptus (Diptera: Culicidae) in Australia.

    Science.gov (United States)

    Nicholson, J; Ritchie, S A; Russell, R C; Webb, C E; Cook, A; Zalucki, M P; Williams, C R; Ward, P; van den Hurk, A F

    2015-05-01

    The presence of Aedes albopictus (Skuse) in the Torres Strait of northern Australia increases the potential for colonization and establishment on the mainland. However, there is a possibility that native species that occupy the same habitats may influence the population performance of Ae. albopictus, potentially affecting the establishment of this species in Australia. Cohabitation experiments were performed with the endemic Aedes notoscriptus (Skuse), which has been found occupying the same larval habitats as Ae. albopictus in the Torres Strait and is the most widespread container-inhabiting Aedes species in Australia. The influence of environmental factors and cohabitation between the two species was examined using different climates, food resource levels, food resource types, and species densities. Survivorship proportions and a population performance index (λ') were calculated and compared. The consequences of increased Ae. notoscriptus densities were reduced survivorship and λ' for Ae. albopictus. Despite this, the mean λ' of Ae. albopictus and Ae. notoscriptus was consistently ≥ 1.06, indicating both species could increase under all conditions, potentially due to increasing conspecific densities negatively affecting Ae. notoscriptus. The outcomes from this study suggest that the preexisting presence of Ae. notoscriptus may not prevent the establishment of Ae. albopictus in Australia. PMID:26334811

  5. Elevation of dopamine level reduces host-seeking activity in the adult female mosquito Aedes albopictus

    OpenAIRE

    Fukumitsu Yuki; Irie Keiichi; Satho Tomomitsu; Aonuma Hitoshi; Dieng Hamady; Ahmad Abu; Nakashima Yukihiko; Mishima Kenichi; Kashige Nobuhiro; Miake Fumio

    2012-01-01

    Abstract Background Mosquito-borne viruses are transmitted to human hosts via blood-feeding behavior of female mosquitoes. Female mosquitoes seek a host to take blood meals (host-seeking behavior). In order to prevent virus infections, it is important to understand how they modulate host-seeking behavior. Dopamine (DA) in the central nervous system acts as a neuromediator that regulates a variety of behaviors in insects. In female mosquitoes, host-seeking behavior increases when DA levels in ...

  6. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Forattini Oswaldo Paulo

    1995-01-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.

  7. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1995-06-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.

  8. Comparación de 2 poblaciones de mosquitos Aedes aegypti de Santiago de Cuba con diferente conducta de reposo

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    Juan A Bisset

    2005-08-01

    Full Text Available Se separaron 2 poblaciones de Aedes aegypti que se colectaron en Santiago de Cuba durante la epidemia de 1997, por manifestar diferentes hábitos de reposo, unos mosquitos reposaban de forma natural en las paredes hasta 1 m de altura (Cepa Santiago de Cuba y otros se encontraron reposando en los techos de las viviendas (Cepa Santiago de Cuba Techo. Ambas cepas no mostraron diferencias significativas en cuanto a sus características morfológicas. Los mosquitos pertenecientes a Santiago de Cuba Techo presentaronn los mismos parches que los de Santiago de Cuba. La resistencia a los insecticidas organofosforados es muy similar en ambas poblaciones, sin embargo, difieren en la alta resistencia al piretroide deltametrina en Santiago de Cuba Techo en comparación con Santiago de Cuba. Desde el punto de vista bioquímico y mediante el uso del sinergista DEF se demostró que las esterasas están asociadas con la alta resistencia a clorpirifos en ambas cepas, no resultando así las MFO, lo cual se demostró con el sinergista piperonil butóxido. Sin embargo, la enzima GST parece ser la responsable de la alta resistencia detectada a deltametrina en Santiago de Cuba Techo por el valor elevado de frecuencia de ese gen en esta cepa. Se utilizó la técnica del ADN polimórfico amplificado a la azar para observar la variabilidad genética entre las 2 poblaciones; los resultados revelaron que existió polimorfismo genético entre las poblaciones en estudio, lo cual pudiera tener una implicación en la ecología y epidemiología del vector.Comparison of 2 populations of Aedes aegypti mosquitoes from Santiago de Cuba with different rest conduct

  9. Reduced Incidence of Chikungunya Virus Infection in Communities with Ongoing Aedes Aegypti Mosquito Trap Intervention Studies - Salinas and Guayama, Puerto Rico, November 2015-February 2016.

    Science.gov (United States)

    Lorenzi, Olga D; Major, Chelsea; Acevedo, Veronica; Perez-Padilla, Janice; Rivera, Aidsa; Biggerstaff, Brad J; Munoz-Jordan, Jorge; Waterman, Stephen; Barrera, Roberto; Sharp, Tyler M

    2016-01-01

    Aedes species mosquitoes transmit chikungunya virus, as well as dengue and Zika viruses, and bite most often during the day.* Infectious mosquito bites frequently occur in and around homes (1,2). Caribbean countries first reported local transmission of chikungunya virus in December 2013, and soon after, chikungunya virus spread throughout the Americas (3). Puerto Rico reported its first laboratory-positive chikungunya case in May 2014 (4), and subsequently identified approximately 29,000 suspected cases throughout the island by the end of 2015.(†) Because conventional vector control approaches often fail to result in effective and sustainable prevention of infection with viruses transmitted by Aedes mosquitoes (5), and to improve surveillance of mosquito population densities, CDC developed an Autocidal Gravid Ovitrap (AGO) (6) to attract and capture the female Aedes aegypti mosquitoes responsible for transmission of infectious agents to humans (Figure). The AGO trap is a simple, low-cost device that requires no use of pesticides and no servicing for an extended period of time (6). PMID:27171600

  10. Genome sequence of the Asian Tiger mosquito, Aedes albopictus, reveals insights into its biology, genetics, and evolution.

    Science.gov (United States)

    Chen, Xiao-Guang; Jiang, Xuanting; Gu, Jinbao; Xu, Meng; Wu, Yang; Deng, Yuhua; Zhang, Chi; Bonizzoni, Mariangela; Dermauw, Wannes; Vontas, John; Armbruster, Peter; Huang, Xin; Yang, Yulan; Zhang, Hao; He, Weiming; Peng, Hongjuan; Liu, Yongfeng; Wu, Kun; Chen, Jiahua; Lirakis, Manolis; Topalis, Pantelis; Van Leeuwen, Thomas; Hall, Andrew Brantley; Jiang, Xiaofang; Thorpe, Chevon; Mueller, Rachel Lockridge; Sun, Cheng; Waterhouse, Robert Michael; Yan, Guiyun; Tu, Zhijian Jake; Fang, Xiaodong; James, Anthony A

    2015-11-01

    The Asian tiger mosquito, Aedes albopictus, is a highly successful invasive species that transmits a number of human viral diseases, including dengue and Chikungunya fevers. This species has a large genome with significant population-based size variation. The complete genome sequence was determined for the Foshan strain, an established laboratory colony derived from wild mosquitoes from southeastern China, a region within the historical range of the origin of the species. The genome comprises 1,967 Mb, the largest mosquito genome sequenced to date, and its size results principally from an abundance of repetitive DNA classes. In addition, expansions of the numbers of members in gene families involved in insecticide-resistance mechanisms, diapause, sex determination, immunity, and olfaction also contribute to the larger size. Portions of integrated flavivirus-like genomes support a shared evolutionary history of association of these viruses with their vector. The large genome repertory may contribute to the adaptability and success of Ae. albopictus as an invasive species. PMID:26483478

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

    Directory of Open Access Journals (Sweden)

    Joy Kean

    2015-03-01

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

  12. Eco-virological survey of Aedes mosquito larvae in selected dengue outbreak areas in Malaysia

    OpenAIRE

    Rohani, A.; A.R. Aidil Azahary; M. Malinda; M.N. Zurainee; H. Rozilawati; W.M.A. Wan Najdah; Lee, H L

    2014-01-01

    Background & objectivesi: Transovarial transmission of dengue virus in the Aedes vectors is now a well-documented phenomenon reported from many parts of the endemic areas in the world, which played an important role in initiating and maintaining the outbreak in human populations. This study investigated the factors affecting breeding habitats and the relationship with transovarial dengue virus in larvae of Aedes aegypti and Ae. albopictus. Methods: Larval surveillance was conducted in den...

  13. Zika virus in Brazil and the danger of infestation by Aedes (Stegomyia) mosquitoes

    OpenAIRE

    Carlos Brisola Marcondes; Maria de Fátima Freire de Melo Ximenes

    2015-01-01

    Abstract Zika virus, already widely distributed in Africa and Asia, was recently reported in two Northeastern Brazilian: State of Bahia and State of Rio Grande do Norte, and one Southeastern: State of São Paulo. This finding adds a potentially noxious virus to a list of several other viruses that are widely transmitted by Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus in Brazil. The pathology and epidemiology, including the distribution and vectors associated with Zika virus, are ...

  14. Potential impacts of climate change on the ecology of dengue and its mosquito vector the Asian tiger mosquito (Aedes albopictus)

    International Nuclear Information System (INIS)

    Shifts in temperature and precipitation patterns caused by global climate change may have profound impacts on the ecology of certain infectious diseases. We examine the potential impacts of climate change on the transmission and maintenance dynamics of dengue, a resurging mosquito-vectored infectious disease. In particular, we project changes in dengue season length for three cities: Atlanta, GA; Chicago, IL and Lubbock, TX. These cities are located on the edges of the range of the Asian tiger mosquito within the United States of America and were chosen as test cases. We use a disease model that explicitly incorporates mosquito population dynamics and high-resolution climate projections. Based on projected changes under the Special Report on Emissions Scenarios (SRES) A1fi (higher) and B1 (lower) emission scenarios as simulated by four global climate models, we found that the projected warming shortened mosquito lifespan, which in turn decreased the potential dengue season. These results illustrate the difficulty in predicting how climate change may alter complex systems. (letter)

  15. Potential impacts of climate change on the ecology of dengue and its mosquito vector the Asian tiger mosquito (Aedes albopictus)

    Science.gov (United States)

    Erickson, R. A.; Hayhoe, K.; Presley, S. M.; Allen, L. J. S.; Long, K. R.; Cox, S. B.

    2012-09-01

    Shifts in temperature and precipitation patterns caused by global climate change may have profound impacts on the ecology of certain infectious diseases. We examine the potential impacts of climate change on the transmission and maintenance dynamics of dengue, a resurging mosquito-vectored infectious disease. In particular, we project changes in dengue season length for three cities: Atlanta, GA; Chicago, IL and Lubbock, TX. These cities are located on the edges of the range of the Asian tiger mosquito within the United States of America and were chosen as test cases. We use a disease model that explicitly incorporates mosquito population dynamics and high-resolution climate projections. Based on projected changes under the Special Report on Emissions Scenarios (SRES) A1fi (higher) and B1 (lower) emission scenarios as simulated by four global climate models, we found that the projected warming shortened mosquito lifespan, which in turn decreased the potential dengue season. These results illustrate the difficulty in predicting how climate change may alter complex systems.

  16. Establishment of a Wolbachia Superinfection in Aedes aegypti Mosquitoes as a Potential Approach for Future Resistance Management.

    Science.gov (United States)

    Joubert, D Albert; Walker, Thomas; Carrington, Lauren B; De Bruyne, Jyotika Taneja; Kien, Duong Hue T; Hoang, Nhat Le Thanh; Chau, Nguyen Van Vinh; Iturbe-Ormaetxe, Iñaki; Simmons, Cameron P; O'Neill, Scott L

    2016-02-01

    Wolbachia pipientis is an endosymbiotic bacterium estimated to chronically infect between 40-75% of all arthropod species. Aedes aegypti, the principle mosquito vector of dengue virus (DENV), is not a natural host of Wolbachia. The transinfection of Wolbachia strains such as wAlbB, wMel and wMelPop-CLA into Ae. aegypti has been shown to significantly reduce the vector competence of this mosquito for a range of human pathogens in the laboratory. This has led to wMel-transinfected Ae. aegypti currently being released in five countries to evaluate its effectiveness to control dengue disease in human populations. Here we describe the generation of a superinfected Ae. aegypti mosquito line simultaneously infected with two avirulent Wolbachia strains, wMel and wAlbB. The line carries a high overall Wolbachia density and tissue localisation of the individual strains is very similar to each respective single infected parental line. The superinfected line induces unidirectional cytoplasmic incompatibility (CI) when crossed to each single infected parental line, suggesting that the superinfection would have the capacity to replace either of the single constituent infections already present in a mosquito population. No significant differences in fitness parameters were observed between the superinfected line and the parental lines under the experimental conditions tested. Finally, the superinfected line blocks DENV replication more efficiently than the single wMel strain when challenged with blood meals from viremic dengue patients. These results suggest that the deployment of superinfections could be used to replace single infections and may represent an effective strategy to help manage potential resistance by DENV to field deployments of single infected strains. PMID:26891349

  17. Impact of Wolbachia on infection with chikungunya and yellow fever viruses in the mosquito vector Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Andrew F van den Hurk

    Full Text Available Incidence of disease due to dengue (DENV, chikungunya (CHIKV and yellow fever (YFV viruses is increasing in many parts of the world. The viruses are primarily transmitted by Aedes aegypti, a highly domesticated mosquito species that is notoriously difficult to control. When transinfected into Ae. aegypti, the intracellular bacterium Wolbachia has recently been shown to inhibit replication of DENVs, CHIKV, malaria parasites and filarial nematodes, providing a potentially powerful biocontrol strategy for human pathogens. Because the extent of pathogen reduction can be influenced by the strain of bacterium, we examined whether the wMel strain of Wolbachia influenced CHIKV and YFV infection in Ae. aegypti. Following exposure to viremic blood meals, CHIKV infection and dissemination rates were significantly reduced in mosquitoes with the wMel strain of Wolbachia compared to Wolbachia-uninfected controls. However, similar rates of infection and dissemination were observed in wMel infected and non-infected Ae. aegypti when intrathoracic inoculation was used to deliver virus. YFV infection, dissemination and replication were similar in wMel-infected and control mosquitoes following intrathoracic inoculations. In contrast, mosquitoes with the wMelPop strain of Wolbachia showed at least a 10(4 times reduction in YFV RNA copies compared to controls. The extent of reduction in virus infection depended on Wolbachia strain, titer and strain of the virus, and mode of exposure. Although originally proposed for dengue biocontrol, our results indicate a Wolbachia-based strategy also holds considerable promise for YFV and CHIKV suppression.

  18. Establishment of a Wolbachia Superinfection in Aedes aegypti Mosquitoes as a Potential Approach for Future Resistance Management.

    Directory of Open Access Journals (Sweden)

    D Albert Joubert

    2016-02-01

    Full Text Available Wolbachia pipientis is an endosymbiotic bacterium estimated to chronically infect between 40-75% of all arthropod species. Aedes aegypti, the principle mosquito vector of dengue virus (DENV, is not a natural host of Wolbachia. The transinfection of Wolbachia strains such as wAlbB, wMel and wMelPop-CLA into Ae. aegypti has been shown to significantly reduce the vector competence of this mosquito for a range of human pathogens in the laboratory. This has led to wMel-transinfected Ae. aegypti currently being released in five countries to evaluate its effectiveness to control dengue disease in human populations. Here we describe the generation of a superinfected Ae. aegypti mosquito line simultaneously infected with two avirulent Wolbachia strains, wMel and wAlbB. The line carries a high overall Wolbachia density and tissue localisation of the individual strains is very similar to each respective single infected parental line. The superinfected line induces unidirectional cytoplasmic incompatibility (CI when crossed to each single infected parental line, suggesting that the superinfection would have the capacity to replace either of the single constituent infections already present in a mosquito population. No significant differences in fitness parameters were observed between the superinfected line and the parental lines under the experimental conditions tested. Finally, the superinfected line blocks DENV replication more efficiently than the single wMel strain when challenged with blood meals from viremic dengue patients. These results suggest that the deployment of superinfections could be used to replace single infections and may represent an effective strategy to help manage potential resistance by DENV to field deployments of single infected strains.

  19. RNA-seq analyses of blood-induced changes in gene expression in the mosquito vector species, Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Olson Ken E

    2011-01-01

    Full Text Available Abstract Background Hematophagy is a common trait of insect vectors of disease. Extensive genome-wide transcriptional changes occur in mosquitoes after blood meals, and these are related to digestive and reproductive processes, among others. Studies of these changes are expected to reveal molecular targets for novel vector control and pathogen transmission-blocking strategies. The mosquito Aedes aegypti (Diptera, Culicidae, a vector of Dengue viruses, Yellow Fever Virus (YFV and Chikungunya virus (CV, is the subject of this study to look at genome-wide changes in gene expression following a blood meal. Results Transcriptional changes that follow a blood meal in Ae. aegypti females were explored using RNA-seq technology. Over 30% of more than 18,000 investigated transcripts accumulate differentially in mosquitoes at five hours after a blood meal when compared to those fed only on sugar. Forty transcripts accumulate only in blood-fed mosquitoes. The list of regulated transcripts correlates with an enhancement of digestive activity and a suppression of environmental stimuli perception and innate immunity. The alignment of more than 65 million high-quality short reads to the Ae. aegypti reference genome permitted the refinement of the current annotation of transcript boundaries, as well as the discovery of novel transcripts, exons and splicing variants. Cis-regulatory elements (CRE and cis-regulatory modules (CRM enriched significantly at the 5'end flanking sequences of blood meal-regulated genes were identified. Conclusions This study provides the first global view of the changes in transcript accumulation elicited by a blood meal in Ae. aegypti females. This information permitted the identification of classes of potentially co-regulated genes and a description of biochemical and physiological events that occur immediately after blood feeding. The data presented here serve as a basis for novel vector control and pathogen transmission

  20. Mosquito larvicidal properties ofOrthosiphon thymiflorus(Roth) Sleesen. (Family:Labiatae) against mosquito vectors,Anopheles stephensi, Culex quinquefasciatus and Aedes aegypti (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    K Kovendan; K Murugan; S Vincent; Donald R Barnard

    2012-01-01

    ABSTRACT Objective:To determine the mosquito larvicidal activities of hexane, chloroform, ethyl acetate, acetone and methanol leaf extract ofOrthosiphon thymiflorus (O. thymiflorus) againstAnopheles stephensi (An. stephensi), Culex quinquefasciatus (Cx. quinquefasciatus) andAedes aegypti (Ae. aegypti).Methods: The larvicidal activity was assayed against three mosquito species at various concentrations ranging from (50-450 ppm) under the laboratory conditions. TheLC50and LC90value of theO. thymiflorus leaf extract was determined by Probit analysis.Results: The LC50values of hexane, chloroform, ethyl acetate, acetone and methanol extract ofO. thymiflorus third instar larvae ofAn. stephensiwereLC50= 201.39, 178.76, 158.06, 139.22 and118.74 ppm;Cx. quinquefasciatus were LC50=228.13, 209.72, 183.35, 163.55 and149.96 ppm andAe. aegyptiwere LC50=215.65, 197.91, 175.05, 154.80 and137.26 ppm, respectively. Maximum larvicidal activity was observed in the methanolic extract followed by acetone, ethyl acetate chloroform and hexane extract. The larval mortality was observed after24h exposure. No mortality was observed in control.Conclusions:The present results suggest that the effective plant crude extracts have potential to be used as an ideal eco-friendly approach for the control of mosquito vectors. This study provides the first report on the larvicidal activity of this plant crude solvent extract of againstAn. stephensi, Cx. quinquefasciatus andAe. aegyptimosquitoes.

  1. A de novo transcriptome of the Asian tiger mosquito, Aedes albopictus, to identify candidate transcripts for diapause preparation

    Directory of Open Access Journals (Sweden)

    Poelchau Monica F

    2011-12-01

    Full Text Available Abstract Background Many temperate insects survive the harsh conditions of winter by undergoing photoperiodic diapause, a pre-programmed developmental arrest initiated by short day lengths. Despite the well-established ecological significance of photoperiodic diapause, the molecular basis of this crucial adaptation remains largely unresolved. The Asian tiger mosquito, Aedes albopictus (Skuse, represents an outstanding emerging model to investigate the molecular basis of photoperiodic diapause in a well-defined ecological and evolutionary context. Ae. albopictus is a medically significant vector and is currently considered the most invasive mosquito in the world. Traits related to diapause appear to be important factors contributing to the rapid spread of this mosquito. To generate novel sequence information for this species, as well as to discover transcripts involved in diapause preparation, we sequenced the transcriptome of Ae. albopictus oocytes destined to become diapausing or non-diapausing pharate larvae. Results 454 GS-FLX transcriptome sequencing yielded >1.1 million quality-filtered reads, which we assembled into 69,474 contigs (N50 = 1,009 bp. Our contig filtering approach, where we took advantage of strong sequence similarity to the fully sequenced genome of Aedes aegypti, as well as other reference organisms, resulted in 11,561 high-quality, conservative ESTs. Differential expression estimates based on normalized read counts revealed 57 genes with higher expression, and 257 with lower expression under diapause-inducing conditions. Analysis of expression by qPCR for 47 of these genes indicated a high correlation of expression levels between 454 sequence data and qPCR, but congruence of statistically significant differential expression was low. Seven genes identified as differentially expressed based on qPCR have putative functions that are consistent with the insect diapause syndrome; three genes have unknown function and represent

  2. 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...

  3. Excretion of dengue virus RNA by Aedes aegypti allows non-destructive monitoring of viral dissemination in individual mosquitoes

    Science.gov (United States)

    Fontaine, Albin; Jiolle, Davy; Moltini-Conclois, Isabelle; Lequime, Sebastian; Lambrechts, Louis

    2016-01-01

    Successful transmission of a vector-borne pathogen relies on a complex life cycle in the arthropod vector that requires initial infection of the digestive tract followed by systemic viral dissemination. The time interval between acquisition and subsequent transmission of the pathogen, called the extrinsic incubation period, is one of the most influential parameters of vector-borne pathogen transmission. However, the dynamic nature of this process is often ignored because vector competence assays are sacrificial and rely on end-point measurements. Here, we report that individual Aedes aegypti mosquitoes release large amounts of dengue virus (DENV) RNA in their excreta that can be non-sacrificially detected over time following oral virus exposure. Further, we demonstrate that detection of DENV RNA in excreta from individual mosquitoes is correlated to systemic viral dissemination with high specificity (0.9–1) albeit moderate sensitivity (0.64–0.89). Finally, we illustrate the potential of our finding to detect biological differences in the dynamics of DENV dissemination in a proof-of-concept experiment. Individual measurements of the time required for systemic viral dissemination, a prerequisite for transmission, will be valuable to monitor the dynamics of DENV vector competence, to carry out quantitative genetics studies, and to evaluate the risk of DENV transmission in field settings. PMID:27117953

  4. Midgut epithelial responses of different mosquito-Plasmodium combinations: the actin cone zipper repair mechanism in Aedes aegypti.

    Science.gov (United States)

    Gupta, Lalita; Kumar, Sanjeev; Han, Yeon Soo; Pimenta, Paulo F P; Barillas-Mury, Carolina

    2005-03-15

    In vivo responses of midgut epithelial cells to ookinete invasion of three different vector-parasite combinations, Aedes aegypti-Plasmodium gallinaceum, Anopheles stephensi-Plasmodium berghei, and A. stephensi-P. gallinaceum, were directly compared by using enzymatic markers and immunofluorescence stainings. Our studies indicate that, in A. aegypti and A. stephensi ookinetes traverse the midgut via an intracellular route and inflict irreversible damage to the invaded cells. These two mosquito species differ, however, in their mechanisms of epithelial repair. A. stephensi detaches damaged cells by an actin-mediated budding-off mechanism when invaded by either P. berghei or P. gallinaceum. In A. aegypti, the midgut epithelium is repaired by a unique actin cone zipper mechanism that involves the formation of a cone-shaped actin aggregate at the base of the cell that closes sequentially, expelling the cellular contents into the midgut lumen as it brings together healthy neighboring cells. Invasion of A. stephensi by P. berghei induced expression of nitric oxide synthase and peroxidase activities, which mediate tyrosine nitration. These enzymes and nitrotyrosine, however, were not induced in the other two vector-parasite combinations examined. These studies indicate that the epithelial responses of different mosquito-parasite combinations are not universal. The implications of these observations to validate animal experimental systems that reflect the biology of natural vectors of human malarias are discussed. PMID:15753303

  5. Using Stable Isotopes of Carbon and Nitrogen to Mark Wild Populations of Anopheles and Aedes Mosquitoes in South-Eastern Tanzania

    Science.gov (United States)

    Opiyo, Mercy A.; Hamer, Gabriel L.; Lwetoijera, Dickson W.; Auckland, Lisa D.; Majambere, Silas; Okumu, Fredros O.

    2016-01-01

    Background Marking wild mosquitoes is important for understanding their ecology, behaviours and role in disease transmission. Traditional insect marking techniques include using fluorescent dyes, protein labels, radioactive labels and tags, but such techniques have various limitations; notably low marker retention and inability to mark wild mosquitoes at source. Stable isotopes are gaining wide spread use for non-invasive marking of arthropods, permitting greater understanding of mosquito dispersal and responses to interventions. We describe here a simple technique for marking naturally-breeding malaria and dengue vectors using stable isotopes of nitrogen (15N) and carbon (13C), and describe potential field applications. Methods We created man-made aquatic mosquito habitats and added either 15N-labelled potassium nitrate or 13C-labelled glucose, leaving non-adulterated habitats as controls. We then allowed wild mosquitoes to lay eggs in these habitats and monitored their development in situ. Pupae were collected promptly as they appeared and kept in netting cages. Emergent adults (in pools of ~4 mosquitoes/pool) and individually stored pupae were desiccated and analysed using Isotope Ratio Mass Spectrometry (IRMS). Findings Anopheles gambiae s.l and Aedes spp. from enriched 13C and enriched 15N larval habitats had significantly higher isotopic levels than controls (P = 0.005), and both isotopes produced sufficient distinction between marked and unmarked mosquitoes. Mean δ15N for enriched females and males were 275.6±65.1 and 248.0±54.6, while mean δ15N in controls were 2.1±0.1 and 3.9±1.7 respectively. Similarly, mean δ13C for enriched females and males were 36.08±5.28 and 38.5±6.86, compared to -4.3±0.2 and -7.9±3.6 in controls respectively. Mean δ15N and δ13C was significantly higher in any pool containing at least one enriched mosquito compared to pools with all unenriched mosquitoes, P<0.001. In all cases, there were variations in standardized

  6. Diet and density dependent competition affect larval performance and oviposition site selection in the mosquito species Aedes albopictus (Diptera: Culicidae

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    Yoshioka Miho

    2012-10-01

    Full Text Available Abstract Background Oviposition-site choice is an essential component of the life history of all mosquito species. According to the oviposition-preference offspring-performance (P-P hypothesis, if optimizing offspring performance and fitness ensures high overall reproductive fitness for a given species, the female should accurately assess details of the heterogeneous environment and lay her eggs preferentially in sites with conditions more suitable to offspring. Methods We empirically tested the P-P hypothesis using the mosquito species Aedes albopictus by artificially manipulating two habitat conditions: diet (measured as mg of food added to a container and conspecific density (CD; number of pre-existing larvae of the same species. Immature development (larval mortality, development time to pupation and time to emergence and fitness (measured as wing length were monitored from first instar through adult emergence using a factorial experimental design over two ascending gradients of diet (2.0, 3.6, 7.2 and 20 mg food/300 ml water and CD (0, 20, 40 and 80 larvae/300 ml water. Treatments that exerted the most contrasting values of larval performance were recreated in a second experiment consisting of single-female oviposition site selection assay. Results Development time decreased as food concentration increased, except from 7.2 mg to 20.0 mg (Two-Way CR ANOVA Post-Hoc test, P > 0.1. Development time decreased also as conspecific density increased from zero to 80 larvae (Two-Way CR ANOVA Post-Hoc test, P . Combined, these results support the role of density-dependent competition for resources as a limiting factor for mosquito larval performance. Oviposition assays indicated that female mosquitoes select for larval habitats with conspecifics and that larval density was more important than diet in driving selection for oviposition sites. Conclusions This study supports predictions of the P-P hypothesis and provides a mechanistic understanding

  7. 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.

  8. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: endemics and emerging outbreaks

    OpenAIRE

    Seirin Lee, S.; Baker, R. E.; Gaffney, E.A.; White, S. M.

    2013-01-01

    The invasion of pest insects often changes or destroys a native ecosystem,and can result in food shortages and disease endemics.Issues such as the environmental effects of chemical control methods,the economic burden of maintaining control strategies and the risk of pestresistance still remain,and mosquito-borne diseases such as malaria and dengue fever prevail in many countries,infecting over100 million worldwide in 2010.One environmentally friendly method for mosquito control is the Sterile...

  9. Container productivity, daily survival rates and dispersal of Aedes aegypti mosquitoes in a high income dengue epidemic neighbourhood of Rio de Janeiro: presumed influence of differential urban structure on mosquito biology

    OpenAIRE

    Mariana Rocha David; Ricardo Lourenço-de-Oliveira; Rafael Maciel de Freitas

    2009-01-01

    Different urban structures might affect the life history parameters of Aedes aegypti and, consequently, dengue transmission. Container productivity, probability of daily survival (PDS) and dispersal rates were estimated for mosquito populations in a high income neighbourhood of Rio de Janeiro. Results were contrasted with those previously found in a suburban district, as well as those recorded in a slum. After inspecting 1,041 premises, domestic drains and discarded plastic pots were identifi...

  10. Molecular characterization of Chikungunya virus isolates from clinical samples and adult Aedes albopictus mosquitoes emerged from larvae from Kerala, South India

    Directory of Open Access Journals (Sweden)

    Niyas Kudukkil P

    2010-08-01

    Full Text Available Abstract Chikungunya virus (CHIKV, an arthritogenic alphavirus, is transmitted to humans by infected Aedes (Ae. aegypti and Ae.albopictus mosquitoes. In the study, reverse-transcription PCR (RT PCR and virus isolation detected CHIKV in patient samples and also in adult Ae.albopictus mosquitoes that was derived from larvae collected during a chikungunya (CHIK outbreak in Kerala in 2009. The CHIKV strains involved in the outbreak were the East, Central and South African (ECSA genotype that had the E1 A226V mutation. The viral strains from the mosquitoes and CHIK patients from the same area showed a close relationship based on phylogenetic analysis. Genetic characterization by partial sequencing of non-structural protein 2 (nsP2; 378 bp, envelope E1 (505 bp and E2 (428 bp identified one critical mutation in the E2 protein coding region of these CHIKV strains. This novel, non-conservative mutation, L210Q, consistently present in both human and mosquito-derived samples studied, was within the region of the E2 protein (amino acids E2 200-220 that determines mosquito cell infectivity in many alpha viruses. Our results show the involvement of Ae. albopictus in this outbreak in Kerala and appearance of CHIKV with novel genetic changes. Detection of virus in adult mosquitoes, emerged in the laboratory from larvae, also points to the possibility of transovarial transmission (TOT of mutant CHIKV strains in mosquitoes.

  11. Molecular characterization of Chikungunya virus isolates from clinical samples and adult Aedes albopictus mosquitoes emerged from larvae from Kerala, South India.

    Science.gov (United States)

    Niyas, Kudukkil P; Abraham, Rachy; Unnikrishnan, Ramakrishnan Nair; Mathew, Thomas; Nair, Sajith; Manakkadan, Anoop; Issac, Aneesh; Sreekumar, Easwaran

    2010-01-01

    Chikungunya virus (CHIKV), an arthritogenic alphavirus, is transmitted to humans by infected Aedes (Ae.) aegypti and Ae.albopictus mosquitoes. In the study, reverse-transcription PCR (RT PCR) and virus isolation detected CHIKV in patient samples and also in adult Ae.albopictus mosquitoes that was derived from larvae collected during a chikungunya (CHIK) outbreak in Kerala in 2009. The CHIKV strains involved in the outbreak were the East, Central and South African (ECSA) genotype that had the E1 A226V mutation. The viral strains from the mosquitoes and CHIK patients from the same area showed a close relationship based on phylogenetic analysis. Genetic characterization by partial sequencing of non-structural protein 2 (nsP2; 378 bp), envelope E1 (505 bp) and E2 (428 bp) identified one critical mutation in the E2 protein coding region of these CHIKV strains. This novel, non-conservative mutation, L210Q, consistently present in both human and mosquito-derived samples studied, was within the region of the E2 protein (amino acids E2 200-220) that determines mosquito cell infectivity in many alpha viruses. Our results show the involvement of Ae. albopictus in this outbreak in Kerala and appearance of CHIKV with novel genetic changes. Detection of virus in adult mosquitoes, emerged in the laboratory from larvae, also points to the possibility of transovarial transmission (TOT) of mutant CHIKV strains in mosquitoes. PMID:20704755

  12. The Eye of the Tiger, the Thrill of the Fight: Effective Larval and Adult Control Measures Against the Asian Tiger Mosquito, Aedes albopictus (Diptera: Culicidae), in North America.

    Science.gov (United States)

    Faraji, Ary; Unlu, Isik

    2016-09-01

    The Asian tiger mosquito, Aedes albopictus (Skuse), is a highly invasive container-inhabiting species with a global distribution. This mosquito, similar to other Stegomyia species such as Aedes aegypti (L.), is highly adapted to urban and suburban areas, and commonly oviposits in artificial containers, which are ubiquitous in these peridomestic environments. The increase in speed and amount of international travel and commerce, coupled with global climate change, have aided in the resurgence and expansion of Stegomyia species into new areas of North America. In many parts of their range, both species are implicated as significant vectors of emerging and re-emerging arboviruses such as dengue, chikungunya, and now Zika. Although rapid and major advances have been made in the field of biology, ecology, genetics, taxonomy, and virology, relatively little has changed in the field of mosquito control in recent decades. This is particularly discouraging in regards to container-inhabiting mosquitoes, because traditional integrated mosquito management (IMM) approaches have not been effective against these species. Many mosquito control programs simply do not possess the man-power or necessary financial resources needed to suppress Ae. albopictus effectively. Therefore, control of mosquito larvae, which is the foundation of IMM approaches, is exceptionally difficult over large areas. This review paper addresses larval habitats, use of geographic information systems for habitat preference detection, door-to-door control efforts, source reduction, direct application of larvicides, biological control agents, area-wide low-volume application of larvicides, hot spot treatments, autodissemination stations, public education, adult traps, attractive-toxic sugar bait methods, lethal ovitraps, barrier-residual adulticides, hand-held ultra-low-volume adulticides, area-wide adulticides applied by ground or air, and genetic control methods. The review concludes with future

  13. Deletion of the NSm virulence gene of Rift Valley fever virus inhibits virus replication in and dissemination from the midgut of Aedes aegypti mosquitoes.

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    Rebekah C Kading

    2014-02-01

    Full Text Available BACKGROUND: Previously, we investigated the role of the Rift Valley fever virus (RVFV virulence genes NSs and NSm in mosquitoes and demonstrated that deletion of NSm significantly reduced the infection, dissemination, and transmission rates of RVFV in Aedes aegypti mosquitoes. The specific aim of this study was to further characterize midgut infection and escape barriers of RVFV in Ae. aegypti infected with reverse genetics-generated wild type RVFV (rRVF-wt or RVFV lacking the NSm virulence gene (rRVF-ΔNSm by examining sagittal sections of infected mosquitoes for viral antigen at various time points post-infection. METHODOLOGY AND PRINCIPAL FINDINGS: Ae. aegypti mosquitoes were fed an infectious blood meal containing either rRVF-wt or rRVF-ΔNSm. On days 0, 1, 2, 3, 4, 6, 8, 10, 12, and 14 post-infection, mosquitoes from each experimental group were fixed in 4% paraformaldehyde, paraffin-embedded, sectioned, and examined for RVFV antigen by immunofluorescence assay. Remaining mosquitoes at day 14 were assayed for infection, dissemination, and transmission. Disseminated infections were observed in mosquitoes as early as three days post infection for both virus strains. However, infection rates for rRVF-ΔNSm were statistically significantly less than for rRVF-wt. Posterior midgut infections in mosquitoes infected with rRVF-wt were extensive, whereas midgut infections of mosquitoes infected with rRVF-ΔNSm were confined to one or a few small foci. CONCLUSIONS/SIGNIFICANCE: Deletion of NSm resulted in the reduced ability of RVFV to enter, replicate, and disseminate from the midgut epithelial cells. NSm appears to have a functional role in the vector competence of mosquitoes for RVFV at the level of the midgut barrier.

  14. 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

  15. Adaptation of the BG-Sentinel trap to capture male and female Aedes albopictus mosquitoes

    OpenAIRE

    Lacroix, R.; Delatte, Hélène; Hue, T.; Dehecq, J. S.; Reiter, P.

    2009-01-01

    In recent years, the remarkable spread of Aedes albopictus (Skuse) (Diptera: Culicidae) throughout the world has drawn attention to this hitherto poorly studied species, particularly after its role in outbreaks of chikungunya fever in the western Indian Ocean and in Italy. Variants of sterile insect technique (SIT), including the release of transgenic males with a dominant lethal gene (RIDL), have been proposed in the search for new and innovative methods of control. Knowledge of male dispers...

  16. 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...

  17. Aedes mosquito salivary immune peptides: boost or block dengue viral infections

    Directory of Open Access Journals (Sweden)

    Natthanej Luplertlop

    2014-02-01

    Full Text Available Dengue virus, one of the most important arthropod-borne viruses, infected to human can severely cause dengue hemorrhagic fever and dengue shock syndrome. There are expected about 50 million dengue infections and 500 000 individuals are hospitalized with dengue hemorrhagic fever, mainly in Southeast Asia, Pacific, and in Americas reported each year. The rapid expansion of global dengue is one of a major public health challenge, together with not yet successful solutions of dengue epidemic control strategies. Thus, these dynamic dengue viral infections exhibited high demographic, societal, and public health infrastructure impacts on human. This review aimed to highlight the current understanding of dengue mosquito immune responses and role of mosquito salivary glands on dengue infection. These information may provide a valuable knowledge of disease pathogenesis, especially in mosquito vector and dengue virus interaction, which may help to control and prevent dengue distribution.

  18. Aedes mosquito salivary immune peptides:boost or block dengue viral infections

    Institute of Scientific and Technical Information of China (English)

    Natthanej Luplertlop

    2014-01-01

    Dengue virus, one of the most important arthropod-borne viruses, infected to human can severely cause dengue hemorrhagic fever and dengue shock syndrome. There are expected about 50 million dengue infections and 500 000 individuals are hospitalized with dengue hemorrhagic fever, mainly in Southeast Asia, Pacific, and in Americas reported each year. The rapid expansion of global dengue is one of a major public health challenge, together with not yet successful solutions of dengue epidemic control strategies. Thus, these dynamic dengue viral infections exhibited high demographic, societal, and public health infrastructure impacts on human. This review aimed to highlight the current understanding of dengue mosquito immune responses and role of mosquito salivary glands on dengue infection. These information may provide a valuable knowledge of disease pathogenesis, especially in mosquito vector and dengue virus interaction, which may help to control and prevent dengue distribution.

  19. Functional characterization of the octenol receptor neuron on the maxillary palps of the yellow fever mosquito, Aedes aegypti.

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    Alan J Grant

    Full Text Available BACKGROUND: 1-Octen-3-ol (octenol is a common attractant released by vertebrates which in combination with carbon dioxide (CO(2 attracts hematophagous arthropods including mosquitoes. A receptor neuron contained within basiconic sensilla on the maxillary palps of adult mosquitoes responds selectively to 1-octen-3-ol. Recently, an odorant receptor (AaegOR8 known to occur on the maxillary palps was expressed in a heterologous system and demonstrated to be selectively sensitive to (R-(--1-octen-3-ol, one of two enantiomeric forms. Lesser responses were elicited by stimulation with the (S-enantiomer and various structural analogs. METHODOLOGY/PRINCIPAL FINDINGS: Here we characterize the specificity of the octenol receptor neuron in the yellow fever mosquito, Aedes aegypti (L., in vivo using single cell recordings. The octenol neuron is exquisitely sensitive to (R-(--1-octen-3-ol; comparable responses to (S-(+-1-octen-3-ol were elicited only at stimulus doses over 100× that required for the (R-enantiomer. An intermediate response closer to that elicited by the (R-(--enantiomer was elicited by racemic 1-octen-3-ol. Small structural changes in (R-(--1-octen-3-ol resulted in large decreases in responses. Increases in spike activity were also elicited in the octenol neuron by 2-undecanone, a known repellent; other repellents (DEET, IR3535 and picaridin were inactive. CONCLUSIONS/SIGNIFICANCE: The results of our electrophysiological studies of the octenol receptor neuron in vivo approximates results of a previous study of the octenol receptor (AaegOR8 with its obligate partner Aaeg\\ORco expressed heterologously in Xenopus oocytes. By comparison of our current results with those of the heterologous expression study, we conclude that specificity of the octenol receptor neuron can be explained largely by characteristics of the OR alone without other associated proteins present in vivo. Our findings show that repellents may have specific stimulatory effects

  20. Transcriptome Profiling and Genetic Study Reveal Amplified Carboxylesterase Genes Implicated in Temephos Resistance, in the Asian Tiger Mosquito Aedes albopictus.

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    Linda Grigoraki

    2015-05-01

    Full Text Available The control of Aedes albopictus, a major vector for viral diseases, such as dengue fever and chikungunya, has been largely reliant on the use of the larvicide temephos for many decades. This insecticide remains a primary control tool for several countries and it is a potential reliable reserve, for emergency epidemics or new invasion cases, in regions such as Europe which have banned its use. Resistance to temephos has been detected in some regions, but the mechanism responsible for the trait has not been investigated.Temephos resistance was identified in an Aedes albopictus population isolated from Greece, and subsequently selected in the laboratory for a few generations. Biochemical assays suggested the association of elevated carboxylesterases (CCE, but not target site resistance (altered AChE, with this phenotype. Illumina transcriptomic analysis revealed the up-regulation of three transcripts encoding CCE genes in the temephos resistant strain. CCEae3a and CCEae6a showed the most striking up-regulation (27- and 12-folds respectively, compared to the reference susceptible strain; these genes have been previously shown to be involved in temephos resistance also in Ae. aegypti. Gene amplification was associated with elevated transcription levels of both CCEae6a and CCEae3a genes. Genetic crosses confirmed the genetic link between CCEae6a and CCEae3a amplification and temephos resistance, by demonstrating a strong association between survival to temephos exposure and gene copy numbers in the F2 generation. Other transcripts, encoding cytochrome P450s, UDP-glycosyltransferases (UGTs, cuticle and lipid biosynthesis proteins, were upregulated in resistant mosquitoes, indicating that the co-evolution of multiple mechanisms might contribute to resistance.The identification of specific genes associated with insecticide resistance in Ae. albopictus for the first time is an important pre-requirement for insecticide resistance management. The genomic

  1. Lantana montevidensis Essential Oil: Chemical Composition and Mosquito Repellent Activity against Aedes aegypti

    Science.gov (United States)

    The essential oil (EO) of Lantana montevidensis (Spreng.) Briq. (L. sellowiana Link & Otto) was investigated for its chemical composition and mosquito repellent activity. The essential oil obtained by hydrodistillation of aerial plant parts was analyzed by GC-FID and GC-MS. The major constituents we...

  2. Wolbachia infection does not alter attraction of the mosquito Aedes (Stegomyia) aegypti to human odours

    NARCIS (Netherlands)

    Turley, A.P.; Smallegange, R.C.; Takken, W.; Zalucki, M.P.; O'Neill, S.L.; McGraw, E.A.

    2014-01-01

    The insect endosymbiont Wolbachia pipientis (Rickettsiales: Rickettsiaceae) is undergoing field trials around the world to determine if it can reduce transmission of dengue virus from the mosquito Stegomyia aegypti to humans. Two different Wolbachia strains have been released to date. The primary ef

  3. Modelling Aedes aegypti mosquito control via transgenic and sterile insect techniques: Endemics and emerging outbreaks

    KAUST Repository

    Seirin Lee, S.

    2013-08-01

    The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the Sterile Insect Technique (SIT). This species-specific method of insect control relies on the mass rearing, sterilization and release of large numbers of sterile insects. An alternative transgenic method is the Release of Insects carrying a Dominant Lethal (RIDL). Our objective is to consider contrasting control strategies for two invasive scenarios via SIT and RIDL: an endemic case and an emerging outbreak. We investigate how the release rate and size of release region influence both the potential for control success and the resources needed to achieve it, under a range of conditions and control strategies, and we discuss advantageous strategies with respect to reducing the release resources and strategy costs (in terms of control mosquito numbers) required to achieve complete eradication of wild-type mosquitoes. © 2013 Elsevier Ltd.

  4. Biting activity of Aedes scapularis (Rondani and Haemagogus mosquitoes in Southern Brazil (Diptera: Culicidae Atividade hematófaga de mosquitos Aedes scapularis (Rondani e Haemagogus no sul do Brasil (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1988-04-01

    Full Text Available The biting activity of a population of Aedes scapularis (Rondani, Haemagogus capricornii Lutz and Hg. leucocelaenus (Dyar and Shannon in Southern Brazil was studied between March 1980 and April 1983. Data were obtained with 25-hour human bait catches in three areas with patchy residual forests, named "Jacaré-Pepira", "Lupo" Farm, and "Sta. Helena" Farm, in the highland region of S. Paulo State (Brazil. Data obtained on Ae. scapularis were compared with those formerly gathered in the "Ribeira'' Valley lowlands, and were similar, except in the "Lupo" Farm study area, where a precrepuscular peak was observed, not recorded at the "Jacaré-Pepira" site or in the "Ribeira" Valley. In all the areas this mosquito showed diurnal and nocturnal activity, but was most active during the evening crepuscular period. These observations support the hypothesis about the successful adaptation of Ae. scapularis to man-made environments and have epidemiological implications that arise from it. As for Haemagogus, results obtained on the "Lupo" and "Sta. Helena" regions agree with previous data obtained in several other regions and show its diurnal activity. The proximity of "Lupo" Farm, where Hg. capricornii and Hg. leucocelaenus showed considerable activity, to "Araraquara" city where Aedes aegypti was recently found, raises some epidemiological considerations about the possibility of urban yellow fever resurgence.No período de março de 1980 a abril de 1983 foi estudada a atividade hematófaga de uma população de Aedes scapularis (Rondani, Haemagogus capricornii Lutz, Hg. leucocelaenus (Dyar e Shannon, na região sul do Brasil. Os dados foram obtidos com o emprego de isca humana, mediante captura de 25 horas de duração e correspondente a três áreas, contendo manchas de floresta residual, denominadas Jacaré-Pepira, Fazenda Lupo e Fazenda Santa Helena. Os resultados relativos a Ae. scapularis foram comparados com as coletas anteriormente feitas em áreas de

  5. 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.

  6. 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.

  7. Deltamethrin-mediated survival, behavior, and oenocyte morphology of insecticide-susceptible and resistant yellow fever mosquitos (Aedes aegypti).

    Science.gov (United States)

    Marriel, Nadja Biondine; Tomé, Hudson Vaner Ventura; Guedes, Raul Carvalho Narciso; Martins, Gustavo Ferreira

    2016-06-01

    Insecticide use is the prevailing control tactic for the mosquito Aedes aegypti, a vector of several human viruses, which leads to ever-increasing problems of insecticide resistance in populations of this insect pest species. The underlying mechanisms of insecticide resistance may be linked to the metabolism of insecticides by various cells, including oenocytes. Oenocytes are ectodermal cells responsible for lipid metabolism and detoxification. The goal of this study was to evaluate the sublethal effects of deltamethrin on survival, behavior, and oenocyte structure in the immature mosquitoes of insecticide-susceptible and resistant strains of A. aegypti. Fourth instar larvae (L4) of both strains were exposed to different concentrations of deltamethrin (i.e., 0.001, 0.003, 0.005, and 0.007 ppm). After exposure, L4 were subjected to behavioral bioassays. Insecticide effects on cell integrity after deltamethrin exposure (at 0.003 or 0.005 ppm) were assessed by processing pupal oenocytes for transmission electron microscopy or TUNEL reaction. The insecticide resistant L4 survived all the tested concentrations, whereas the 0.007-ppm deltamethrin concentration had lethal effects on susceptible L4. Susceptible L4 were lethargic and exhibited less swimming activity than unexposed larvae, whereas the resistant L4 were hyperexcited following exposure to 0.005 ppm deltamethrin. No sublethal effects and no significant cell death were observed in the oenocytes of either susceptible or resistant insects exposed to deltamethrin. The present study illustrated the different responses of susceptible and resistant strains of A. aegypti following exposure to sublethal concentration of deltamethrin, and demonstrated how the behavior of the immature stage of the two strains varied, as well as oenocyte structure following insecticide exposure. PMID:26943998

  8. Infection with a Virulent Strain of Wolbachia Disrupts Genome Wide-Patterns of Cytosine Methylation in the Mosquito Aedes aegypti.

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    Yixin H Ye

    Full Text Available Cytosine methylation is one of several reversible epigenetic modifications of DNA that allow a greater flexibility in the relationship between genotype and phenotype. Methylation in the simplest models dampens gene expression by modifying regions of DNA critical for transcription factor binding. The capacity to methylate DNA is variable in the insects due to diverse histories of gene loss and duplication of DNA methylases. Mosquitoes like Drosophila melanogaster possess only a single methylase, DNMT2.Here we characterise the methylome of the mosquito Aedes aegypti and examine its relationship to transcription and test the effects of infection with a virulent strain of the endosymbiont Wolbachia on the stability of methylation patterns.We see that methylation in the A. aegypti genome is associated with reduced transcription and is most common in the promoters of genes relating to regulation of transcription and metabolism. Similar gene classes are also methylated in aphids and honeybees, suggesting either conservation or convergence of methylation patterns. In addition to this evidence of evolutionary stability, we also show that infection with the virulent wMelPop Wolbachia strain induces additional methylation and demethylation events in the genome. While most of these changes seem random with respect to gene function and have no detected effect on transcription, there does appear to be enrichment of genes associated with membrane function. Given that Wolbachia lives within a membrane-bound vacuole of host origin and retains a large number of genes for transporting host amino acids, inorganic ions and ATP despite a severely reduced genome, these changes might represent an evolved strategy for manipulating the host environments for its own gain. Testing for a direct link between these methylation changes and expression, however, will require study across a broader range of developmental stages and tissues with methods that detect splice variants.

  9. Further extension of the range of the rock pool mosquito, Aedes atropalpus, via tire breeding.

    Science.gov (United States)

    Nawrocki, S J; Craig, G B

    1989-03-01

    In the past, Aedes atropalpus was limited to those areas of the eastern U.S. and Canada that had rivers or shorelines with large rocks containing rock pools. In the last 10 years, many new records of larval breeding in scrap tires have accumulated. We present records of larval breeding in non-rock pool containers for 54 counties; most are far from the original range. The species has not only found a new habitat but has greatly extended its range via commercial transport of scrap tires. PMID:2708986

  10. Larvicidal and repellent effect of some Tribulus terrestris L., (Zygophyllaceae extracts against the dengue fever mosquito, Aedes aegypti (Diptera: Culicidae

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    Tarek M.Y. El-Sheikh

    2016-01-01

    Full Text Available 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 by acetone extract with LC50 173.2 ppm and finally ethanolic extract with LC50 376.4 ppm. Moreover, the acetone and petroleum ether extracts exerted a highly delayed toxic effect on the pupae and adults resulted from treated larvae, where the pupal mortality was 57.1% and 100% at concentrations 400 and 100 ppm, respectively. Also, the petroleum ether and acetone extracts showed reduction effects on adult emergence. The repellent action of the plant extracts tested was varied depending on the solvent used in extraction and the dose of the extract. The most effective plant extract that evoked 100% repellency or biting deterrence was petroleum ether extract at a dose of 1.5 mg/cm2 compared with 100% repellency for commercial formulation, N,N-diethyl-3-methylbenzamide (DEET at the same dose. Hence, these extracts can be used as an effective alternative to the existing synthetic pesticides for the control of Ae. aegypti.

  11. Human impacts have shaped historical and recent evolution in Aedes aegypti, the dengue and yellow fever mosquito.

    Science.gov (United States)

    Brown, Julia E; Evans, Benjamin R; Zheng, Wei; Obas, Vanessa; Barrera-Martinez, Laura; Egizi, Andrea; Zhao, Hongyu; Caccone, Adalgisa; Powell, Jeffrey R

    2014-02-01

    Although anthropogenic impacts are often considered harmful to species, human modifications to the landscape can actually create novel niches to which other species can adapt. These "domestication" processes are especially important in the context of arthropod disease vectors, where ecological overlap of vector and human populations may lead to epidemics. Here, we present results of a global genetic study of one such species, the dengue and yellow fever mosquito, Aedes aegypti, whose evolutionary history and current distribution have been profoundly shaped by humans. We used DNA sequences of four nuclear genes and 1504 single nucleotide polymorphism (SNP) markers developed with restriction-site associated DNA (RAD) sequencing to test the hypothesis that Ae. aegypti originated in Africa, where a domestic form arose and spread throughout the tropical and subtropical world with human trade and movement. Results confirmed African ancestry of the species, and supported a single subspeciation event leading to the pantropical domestic form. In addition, genetic data strongly supported the hypothesis that human trade routes first moved domestic Ae. aegypti out of Africa into the New World, followed by a later invasion from the New World into Southeast Asia and the Pacific. These patterns of domestication and invasion are relevant to many species worldwide, as anthropogenic forces increasingly impact evolutionary processes. PMID:24111703

  12. First report of field evolved resistance to agrochemicals in dengue mosquito, Aedes albopictus (Diptera: Culicidae, from Pakistan

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    Shehzad Khurram

    2011-07-01

    Full Text Available Abstract Background Agrochemicals have been widely used in Pakistan for several years. This exposes mosquito populations, particularly those present around agricultural settings, to an intense selection pressure for insecticide resistance. The aim of the present study was to investigate the toxicity of representative agrochemicals against various populations of Aedes albopictus (Skuse collected from three different regions from 2008-2010. Results For organophosphates and pyrethroids, the resistance ratios compared with susceptible Lab-PK were in the range of 157-266 fold for chlorpyrifos, 24-52 fold for profenofos, 41-71 fold for triazofos, and 15-26 fold for cypermethrin, 15-53 fold for deltamethrin and 21-58 fold for lambdacyhalothrin. The resistance ratios for carbamates and new insecticides were in the range of 13-22 fold for methomyl, 24-30 fold for thiodicarb, and 41-101 fold for indoxacarb, 14-27 fold for emamectin benzoate and 23-50 fold for spinosad. Pair wise comparisons of the log LC50s of insecticides revealed correlation among several insecticides, suggesting a possible cross resistance mechanism. Moreover, resistance remained stable across 3 years, suggesting field selection for general fitness had also taken place for various populations of Ae. albopictus. Conclusion Moderate to high level of resistance to agrochemicals in Pakistani field populations of Ae. albopictus is reported here first time. The geographic extent of resistance is unknown but, if widespread, may lead to problems in future vector control.

  13. Identification of a major Quantitative Trait Locus determining resistance to the organophosphate temephos in the dengue vector mosquito Aedes aegypti.

    Science.gov (United States)

    Paiva, Marcelo H S; Lovin, Diane D; Mori, Akio; Melo-Santos, Maria A V; Severson, David W; Ayres, Constância F J

    2016-01-01

    Organophosphate insecticides (OP) have extensively been used to control mosquitoes, such as the vector Aedes aegypti. Unfortunately, OP resistance has hampered control programs worldwide. We used Quantitative Trait Locus (QTL) mapping to evaluate temephos resistance in two F1 intercross populations derived from crosses between a resistant Ae. aegypti strain (RecR) and two susceptible strains (MoyoD and Red). A single major effect QTL was identified on chromosome 2 of both segregating populations, named rtt1 (resistance to temephos 1). Bioinformatics analyses identified a cluster of carboxylesterase genes (CCE) within the rtt1 interval. qRT-PCR demonstrated that different CCEs were up-regulated in F2 resistant individuals from both crosses. However, none exceeded the 2-fold expression. Primary mechanisms for temephos resistance may vary between Ae. aegypti populations, yet also appear to support previous findings suggesting that multiple linked esterase genes may contribute to temephos resistance in the RecR strain as well as other populations. PMID:26576515

  14. Mosquito larvicidal and ovicidal properties of Eclipta alba (L.) Hassk (Asteraceae) against chikungunya vector, Aedes aegypti (Linn.) (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    M Govindarajan; P Karuppannan

    2011-01-01

    Objective: The present study deals with the investigation of larvicidal and ovicidal activities of benzene, hexane, ethyl acetate, methanol and chloroform leaf extract of Eclipta alba (E. alba) against dengue vector, Aedes aegypti (Ae. Aegypti). Methods: Twenty five early III instar larvae of Ae. aegypti was exposed to various concentrations (50-300 ppm) and was assayed in the laboratory by using the protocol of WHO 2005; the 24 h LC50 values of the E. alba leaf extract was determined by Probit analysis. For ovicidal activity, slightly modified method of Su and Mulla was performed. The ovicidal activity was determined against Ae. aegypti to various concentrations ranging from 100-350 ppm under the laboratory conditions. The egg hatch rates were assessed 48 h post treatment. Results: The LC50 values of benzene, hexane, ethyl acetate, methanol and chloroform extract of E. alba against early third instar larvae of Ae. aegypti were 151.38, 165.10, 154.88, 127.64 and 146.28 ppm, respectively. Maximum larvicidal activity was observed in the methanol extract followed by chloroform, benzene, ethyl acetate and hexane extract. No mortality was observed in control. Among five solvent tested the methanol extract was found to be most effective for ovicidal activity against Ae. aegypti. The methanol extracts exerted 100% mortality (zero hatchability) at 300 ppm. Conclusions: From the results it can be concluded the crude extract of E. alba was an excellent potential for controlling Ae. aegypti mosquito.

  15. Delivery of chitosan/dsRNA nanoparticles for silencing of wing development vestigial (vg) gene in Aedes aegypti mosquitoes.

    Science.gov (United States)

    Ramesh Kumar, D; Saravana Kumar, P; Gandhi, M Rajiv; Al-Dhabi, Naif Abdullah; Paulraj, M Gabriel; Ignacimuthu, S

    2016-05-01

    RNA interference (RNAi) has been used as a gene silencing strategy by the introduction of long double stranded RNA (dsRNA) for the control of pest insects. The aim of the present study was to examine whether the expression of vg gene which is responsible for wing development, can be repressed by chitosan/dsRNA based nanoparticles in Aedes aegypti. The vestigial gene (vg) was amplified from adult mosquito and cloned in pLitmus28i vector. Genetically engineered recombinant plasmid was transformed into RNase III deficient strain for synthesis of bacterially expressed dsRNA. Nanoparticles were prepared via electrostatic interaction between cationic polymer chitosan and anionic nucleic acids (dsRNA). The formation of chitosan/dsRNAnanoparticles and their size were confirmed by Atomic force microscopy (AFM). Chitosan/dsRNA mediated knockdown of Enhanced Green Fluorescence Protein (EGFP) was demonstrated in Sf21 cells. Further, we tested whether such an approach could be used to target vg gene in Ae. aegypti. The results showed that chitosan/dsRNA caused significant mortality, delayed growth development and caused adult wing-malformation. A qRT-PCR analysis confirmed that the chitosan/dsRNA mediated transcriptional level was downregulated. Our findings suggest that vg gene intervention strategies through RNAi can emerge as viable option for pest control. PMID:26794313

  16. Mosquito larvicidal properties of Impatiens balsamina (Balsaminaceae) against Anopheles stephensi, Aedes aegypti and Culex quinquefasciatus (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan; Mohan Rajeswary

    2014-01-01

    Objective: To assess the larvicidal potential of the crude benzene, chloroform, ethyl acetate and methanol solvent extracts of the medicinal plant Impatiens balsamina against Anopheles stephensi(An. stephensi), Aedes aegypti (Ae. aegypti) and Culex quinquefasciatus (Cx. quinquefasciatus). Methods: Twenty five third instar larvae of An. stephensi, Ae. aegypti and Cx. quinquefasciatus were exposed to various concentrations and were assayed in the laboratory by using the protocol recommended by WHO. The larval mortality was observed after 24 h of treatment. Results: Among extracts tested, the highest larvicidal activity was observed in leaf methanol extract of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus with the LC50 and LC90 values 98.04, 119.68, 125.06 and 172.93, 210.14, 220.60 mg/L, respectively. Conclusions:From the results it can be concluded that the larvicidal effect of Impatiens balsamina against An. stephensi, Ae. aegypti and Cx. quinquefasciatus make this plant product promising as an alternative to synthetic insecticide in mosquito control programs.

  17. Yellow Fever Virus in Haemagogus leucocelaenus and Aedes serratus Mosquitoes, Southern Brazil, 2008

    OpenAIRE

    Cardoso, Jáder da C.; de Almeida, Marco A.B.; dos Santos, Edmilson; da Fonseca, Daltro F.; Sallum, Maria A.M.; Noll, Carlos A.; Monteiro, Hamilton A. de O.; Cruz, Ana C.R.; Carvalho, Valéria L.; Pinto, Eliana V.; Castro, Francisco C.; Neto, Joaquim P. Nunes; Segura, Maria N.O.; Vasconcelos, Pedro F.C.

    2010-01-01

    Yellow fever virus (YFV) was isolated from Haemagogus leucocelaenus mosquitoes during an epizootic in 2001 in the Rio Grande do Sul State in southern Brazil. In October 2008, a yellow fever outbreak was reported there, with nonhuman primate deaths and human cases. This latter outbreak led to intensification of surveillance measures for early detection of YFV and support for vaccination programs. We report entomologic surveillance in 2 municipalities that recorded nonhuman primate deaths. Mosq...

  18. In vitro characterization and mosquito (Aedes aegypti) repellent activity of essential-oils-loaded nanoemulsions.

    Science.gov (United States)

    Nuchuchua, Onanong; Sakulku, Usawadee; Uawongyart, Napaporn; Puttipipatkhachorn, Satit; Soottitantawat, Apinan; Ruktanonchai, Uracha

    2009-01-01

    The nanoemulsions composed of citronella oil, hairy basil oil, and vetiver oil with mean droplet sizes ranging from 150 to 220 nm were prepared and investigated both in vitro and in vivo. Larger emulsion droplets (195-220 nm) shifted toward a smaller size (150-160 nm) after high-pressure homogenization and resulted in higher release rate. We proposed that thin films obtained from the nanoemulsions with smaller droplet size would have higher integrity, thus increasing the vaporization of essential oils and subsequently prolonging the mosquito repellant activity. The release rates were fitted with Avrami's equations and n values were in the same range of 0.6 to 1.0, implying that the release of encapsulated limonene was controlled by the diffusion mechanism from the emulsion droplet. By using high-pressure homogenization together with optimum concentrations of 5% (w/w) hairy basil oil, 5% (w/w) vetiver oil (5%), and 10% (w/w) citronella oil could improve physical stability and prolong mosquito protection time to 4.7 h due to the combination of these three essential oils as well as small droplet size of nanoemulsion. PMID:19862624

  19. Household survey of container-breeding mosquitoes and climatic factors influencing the prevalence of Aedes aegypti (Diptera:Culicidae) in Makkah City, Saudi Arabia

    Institute of Scientific and Technical Information of China (English)

    Al Thabiany Aziz; Hamdan Ahmad; Wan Fatma Zuharah; Ahmad Saad Ramli; Fumio Miake; Hamady Dieng; Abu Hassan Ahmad; Jazem A Mahyoub; Abdulhafis M Turkistani; Hatabbi Mesed; Salah Koshike; Tomomitsu Satho; MR Che Salmah

    2012-01-01

    Objective: To investigate the prevalence of container breeding mosquitoes with emphasis on the seasonality and larval habitats of Aedes aegypti (Ae. aegypti) in Makkah City, adjoining an environmental monitoring and dengue incidence. Methods: Monthly visits were performed between April 2008 and March 2009 to randomly selected houses. During each visit, mosquito larvae were collected from indoors and outdoors containers by either dipping or pipetting. Mosquitoes were morphologically identified. Data on temperature, relative humidity, rain/precipitations during the survey period was retrieved from governmental sources and analyzed. Results: The city was warmer in dry season (DS) than wet season (WS). No rain occurred at all during DS and even precipitations did fall, wetting events were much greater during WS. Larval survey revealed the co-breeding of Aedes, Culex and Anopheles in a variety of artificial containers in and around homes. 32109 larvae representing 1st , 2nd, 3rd, and 4th stages were collected from 22618 container habitats. Culicines was far the commonest and Aedes genus was as numerous as the Culex population. Ae. aegypti larval abundance exhibited marked temporal variations, overall, being usually more abundant during WS. Ten types of artificial containers were found with developing larvae. 70% of these habitats were located indoors. 71.42% of indoor containers were permanent and 28.58% was semi-permanent during WS. Cement tanks was the only container type permanent during DS. Ae. aegypti larval indices (CI, HI, BI) recorded were greater during WS. Conclusions: Taken together, these results indicate a high risk of dengue transmission in the holy city.

  20. Insecticidal potency of Aspergillus terreus against larvae and pupae of three mosquito species Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-11-01

    Microbial control agents offer alternatives to chemical pest control, as they can be more selective than chemical insecticides. The present study evaluates the mosquito larvicidal and pupicidal potential of fungus mycelia using ethyl acetate and methanol solvent extracts produced by Aspergillus terreus against Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti. The A. terreus mycelia were extracted after 15 days from Sabouraud dextrose broth medium. The ethyl acetate extracts showed lethal concentration that kills 50% of the exposed larvae (LC50) and lethal concentration that kills 90% of the exposed larvae (LC90) values of the first, second, third, and fourth instar larvae of An. stephensi (LC50 = 97.410, 102.551, 29.802, and 8.907; LC90 = 767.957, 552.546, 535.474, and 195.677 μg/ml), Cx. quinquefasciatus (LC50 = 89.584, 74.689, 68.265, and 67.40; LC90 = 449.091, 337.355, 518.793, and 237.347 μg/ml), and Ae. aegypti (LC50 = 83.541, 84.418, 80.407, and 95.926; LC90 = 515.464, 443.167, 387.910, and 473.998 μg/ml). Pupicidal activity of mycelium extracts was tested against An. stephensi (LC50 = 25.228, LC90 = 140.487), Cx. quinquefasciatus (LC50 = 54.525, LC90 = 145.366), and Ae. aegypti (LC50 = 10.536, LC90 = 63.762 μg/ml). At higher concentration (500 μg/ml), mortality starts within the first 6 h of exposure. One hundred percent mortality occurs at 24-h exposure. The overall result observed that effective activity against selected mosquito larvae and pupae after 24 h was a dose and time-dependent activity. These ensure that the resultant mosquito population reduction is substantial even where the larvicidal and pupicidal potential is minimal. The FTIR spectra of ethyl acetate extract reflect prominent peaks (3448.32, 3000.36, 2914.59, 2118.73, 1668.21, 1436.87, 1409.02, 954.33, 901.13, and 704.67 cm(-1)). The spectra showed a sharp absorption band at 1314.66 cm(-1) assigned to wagging vibration of

  1. Winter refuge for Aedes aegypti and Ae. albopictus mosquitoes in Hanoi during Winter.

    Science.gov (United States)

    Tsunoda, Takashi; Cuong, Tran Chi; Dong, Tran Duc; Yen, Nguyen Thi; Le, Nguyen Hoang; Phong, Tran Vu; Minakawa, Noboru

    2014-01-01

    Dengue occurs throughout the year in Hanoi, Vietnam, despite winter low temperatures concrete tanks and this preference increased in winter. Even in winter, the lowest water temperature found in concrete tanks was >14°C, exceeding the developmental zero point of Ae. aegypti. Although jars, drums and concrete tanks were the dominant containers previously (1994-97) in Hanoi, currently the percentage of residences with concrete tanks was still high while jars and drums were quite low. Our study showed that concrete tanks with broken lids allowing mosquitoes access were important winter refuge for Ae. aegypti. We also indicate a concern about concrete tanks serving as foci for Ae. aegypti to expand their distribution in cooler regions. PMID:24752230

  2. Infestation by the Aedes aegypti (Diptera: Culicidae mosquito in the town of Chapeco, Santa Catarina, Brazil

    Directory of Open Access Journals (Sweden)

    Samara Tessaro Balsan

    2013-06-01

    Full Text Available Dengue fever became a public health problem and it has caused concern among health professionals. This study aimed to evaluate the conditioning factors for the occurrence of dengue fever in the town of Chapeco, Santa Catarina, Brazil. One analyzed the information available on the Information System on Yellow Fever and Dengue Fever (SISFAD and conducted a survey through a semi-structured questionnaire applied to the population. The analyses indicate the association of infestation by the mosquito which transmits dengue to improperly handled garbage and to the rainwater collection deposit, as well as to the residential environment. The prevention of dengue in the town of Chapeco involves the implementation of public policies on health environmental education for proper separation and disposal of solid waste and improvements in the public water supply system. Educational campaigns aimed at care in the home environment are also needed.

  3. Evaluation of some aromatic plant extracts for mosquito larvicidal potential against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi.

    Science.gov (United States)

    Jayaraman, M; Senthilkumar, A; Venkatesalu, V

    2015-04-01

    In the present investigation, larvicidal potential of hexane, choloroform, ethyl acetate, acetone, and methanol extracts of seven aromatic plants, viz., Blumea mollis, Chloroxylon swietenia, Clausena anisata, Feronia limnonia, Lantana camera, Plectranthus amboinicus, and Tagetes erecta were screened against Culex quinquefasciatus, Aedes aegypti, and Anopheles stephensi. The larval mortality was observed after 12 and 24 h of exposure period. The results revealed that all the extracts showed varied levels of larvicidal activity against the mosquito species tested. However, the ethyl acetate extract of Chloroxylon swietenia showed the remarkable larvicidal activity against C. quinquefasciatus, Ae. aegypti, and An. stephensi. After 12 h of exposure period, the larvicidal activity was LC50 = 194.22 and LC90 = 458.83 ppm (C. quinquefasciatus), LC50 = 173.04 and LC90 = 442.73 ppm (Ae. aegypti), and LC50 = 167.28 and LC90 = 433.07 ppm (An. stephensi), and the larvicidal activity after 24-h exposure period was LC50 = 94.12 and LC90 = 249.83 ppm (C. quinquefasciatus), LC50 = 80.58 and LC90 = 200.96 ppm (Ae. aegypti), and LC50 = 76.24 and LC90 = 194.51 ppm (An. stephensi). The larvicidal potential of other plant extracts were in order of ethyl acetate extract of Clausena anisata > methanol extract of P. amboinicus > acetone extract of F. limonia > methanol extract of T. erecta > methanol extract of B. mollis > and methanol extract of L. camera. The results of the present study offer a possible way for further investigations to find out the active molecule responsible for the activity. PMID:25630696

  4. Host-Feeding Patterns of Native Culex pipiens and Invasive Aedes albopictus Mosquitoes (Diptera: Culicidae) in Urban Zones From Barcelona, Spain

    DEFF Research Database (Denmark)

    Muñoz, Joaquin; Eritja, Roger; Alcaide, Miguel;

    2011-01-01

    mosquito Aedes albopictus (Skuse) represents an example of how an invasive species can alter the risk of viral transmission to humans. Blood meal molecular identiÞcation from two sympatric mosquito species (the invasive Ae. albopictus and the native Culex pipiens) was carried out by polymerase chain...... tropical viruses such as dengue and chikungunya. However, in the studied area, the presence of this invasive species would have a negligible effect on the transmission of zoonotic agents such as West Nile virus. However, Cx. pipiens could amplify and transmit West Nile virus, but avian contribution to its...... reaction-based methods. Samples were collected in Barcelona metropolitan area, Spain, from June to October 2009 as part of a monitoring-control program. Blood meals were identiÞed to the species level in 30 Ae. albopictus and 43 Cx. pipiens. Ae. albopictus acquired blood exclusively from human hosts (100...

  5. Characterization of a novel circo-like virus in Aedes vexans mosquitoes from Germany: evidence for a new genus within the family Circoviridae.

    Science.gov (United States)

    Garigliany, Mutien-Marie; Börstler, Jessica; Jöst, Hanna; Badusche, Marlis; Desmecht, Daniel; Schmidt-Chanasit, Jonas; Cadar, Daniel

    2015-04-01

    Over recent decades, metagenomic studies have expanded the number of newly described, often unclassified, viruses within the family Circoviridae. Using broad-spectrum circovirus and cyclovirus PCRs, we characterized a novel circo-like virus in Aedes vexans mosquitoes from Germany whose main putative ORFs shared very low amino acid identity with those of previously characterized circoviruses and cycloviruses. Phylogenetic and genetic distance analysis revealed that this new virus species defined, together with previously described mosquito- and bat faeces-derived circo-like viruses, a different genus, tentatively called Krikovirus, within the family Circoviridae. We further demonstrated that viruses of the putative genus Krikovirus all shared a genomic organization that was unique among the family Circoviridae. Further investigations are needed to determine the host range, tissue tropism and transmission route(s). This report increases the current knowledge of the genetic diversity and evolution of the members of the family Circoviridae. PMID:25535324

  6. Bioactivity of seagrass against the dengue fever mosquito Aedes aegypti larvae

    Institute of Scientific and Technical Information of China (English)

    M Syed Ali; S Ravikumar; J Margaret Beula

    2012-01-01

    Objective: To identify the larvicidal activity of the seagrass extracts. Methods: Seagrass extracts, Syringodium isoetifolium (S. isoetifolium), Cymodocea serrulata and Halophila beccarii, were dissolved in DMSO to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Aedes aegypti (Ae. aegypti) were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01 mg–0.1 mg). After 24 h the mortality rate was identified with the formulae [(%of test mortality- %of control mortality)/(100- %of control mortality)]í100. Each experiment was conducted with three replicates and a concurrent control group. A control group consisted of 1 mL of DMSO and 199 mL of distilled water only. Results:The root extract of S. isoetifolium showed maximum larvicidal activity with minimum concentration of extract of LC50= 0.0 604± 0.0 040)μg/mL with lower confidence limit (LCL)-upper confidence limit (UCL)=(0.051-0.071) and LC90=0.0 972μg/mL followed by leaf extract of S. isoetifolium showed LC50= (0.062± 0.005)μg/mL. The regression equation of root and leaf extract of S. isoetifolium for 4th instar larvae were Y=4.909+1.32x (R2=0.909) and Y=2.066+1.21x (R2=0.897) respectively. The results of the preliminary phytochemical constituents shows the presence of saponin, steroids, terpenoid, phenols, protein and sugars. Conclusions: From the present study the ethanolic extracts of seagrass of S. isoetifolium possesses lead compound for development of larvicidal activity.

  7. Mosquito larvicidal efficacy of seaweed extracts against dengue vector of Aedes aegypti

    Institute of Scientific and Technical Information of China (English)

    Ravikumar S; M Syed Ali; J Margaret Beula

    2011-01-01

    Objective:To identify the larvicidal activity of the seaweed extracts. Methods:Seaweed extracts of Enteromorpha intestinalis (E. intestinalis), Dictyota dichotoma (D. dichotoma) and Acanthopora spicifera (A. spicifera) were dissolved in dimethylsulfoxide (DMSO) to prepare a graded series of concentration. Batches of 25 early 4th instars larvae of Aedes aegypti were transferred to 250 mL enamel bowl containing 199 mL of distilled water and 1 mL of plant extracts (0.01-0.1 mg). Each experiment was conducted in three replicates. A control group consisted of 1 mL of DMSO and 99 mL of distilled water only. After 24 h, the percentage of mortality was identified with the formula: %of mortality=[(%of test mortality-%of control mortality)/(100-%of control mortality)]×100. Results:The extract of D. dichotoma showed minimum level of LC50 value (0.068 3±0.008 4 μg/mL) and LC90 value was 0.140 1. The regression equations of D. dichotoma and E. intestinalis for 4th instar larvae were Y=0.333 + 0.684x (R2=0.946) and Y=0.600 + 0.781x (R2=0.812), respectively. The results of the preliminary phytochemical constituents showed the presence of saponin, steroids, terpenoid, phenols, protein and sugars. Conclusions:It can be concluded from the present study that, the ethanolic extracts of seaweed of D. dichotoma possess active compounds for development of larvicidal ativity.

  8. Aerial ultra-low-volume application of naled: impact on nontarget imperiled butterfly larvae (Cyclargus thomasi bethunebakeri) and efficacy against adult mosquitoes (Aedes taeniorhynchus).

    Science.gov (United States)

    Zhong, H; Hribar, L J; Daniels, J C; Feken, M A; Brock, C; Trager, M D

    2010-12-01

    We assessed the exposure and acute toxicity of naled, applied aerially as an ultra-low-volume spray for mosquito control, on late instar larvae of the Miami blue (Cyclargus thomasi bethunebakeri) (Comstock and Huntington 1943) (Lepidoptera: Lycaenidae), an imperiled South Florida butterfly. We concurrently evaluated the control efficacy against caged adult female salt-marsh mosquitoes (Aedes taeniorhynchus) (Wiedemann 1821) (Diptera: Culicidae). This 3-yr study was conducted in north Key Largo (Monroe County, FL) beginning in 2006. The field trials incorporated 15 sampling stations: nine in the target spray zone, three in the spray drift zone at varying distances from the target zone, and three in the control zone not subjected to naled spray drift. A total of six field spray trials were completed, three at an altitude of 30.5 m (100 feet), and three at 45.7 m (150 feet). For all trials, the ultra-low-volume application of Trumpet EC insecticide (78% naled) at a rate of 54.8 ml/ha (0.75 fl. oz/acre) was effective in killing caged adult mosquitoes in the target zone. Butterfly larvae survival was significantly reduced in the spray zone compared with drift and control zones. Analysis of insecticide residue data revealed that the mortality of the late instar butterfly larvae was a result of exposure to excess residues of naled. Additional research is needed to determine mitigation strategies that can limit exposure of sensitive butterflies to naled while maintaining mosquito control efficacy. PMID:22182563

  9. Structure of an Odorant-Vinding Protein form the Mosquito Aedes aegypti Suggests a Binding Pocket Covered by a pH-Sensitive

    Energy Technology Data Exchange (ETDEWEB)

    N Leite; R Krogh; W Xu; Y Ishida; J Iulek; W Leal; G Oliva

    2011-12-31

    The yellow fever mosquito, Aedes aegypti, is the primary vector for the viruses that cause yellow fever, mostly in tropical regions of Africa and in parts of South America, and human dengue, which infects 100 million people yearly in the tropics and subtropics. A better understanding of the structural biology of olfactory proteins may pave the way for the development of environmentally-friendly mosquito attractants and repellents, which may ultimately contribute to reduction of mosquito biting and disease transmission. Previously, we isolated and cloned a major, female-enriched odorant-binding protein (OBP) from the yellow fever mosquito, AaegOBP1, which was later inadvertently renamed AaegOBP39. We prepared recombinant samples of AaegOBP1 by using an expression system that allows proper formation of disulfide bridges and generates functional OBPs, which are indistinguishable from native OBPs. We crystallized AaegOBP1 and determined its three-dimensional structure at 1.85 {angstrom} resolution by molecular replacement based on the structure of the malaria mosquito OBP, AgamOBP1, the only mosquito OBP structure known to date. The structure of AaegOBP1 (= AaegOBP39) shares the common fold of insect OBPs with six {alpha}-helices knitted by three disulfide bonds. A long molecule of polyethylene glycol (PEG) was built into the electron-density maps identified in a long tunnel formed by a crystallographic dimer of AaegOBP1. Circular dichroism analysis indicated that delipidated AaegOBP1 undergoes a pH-dependent conformational change, which may lead to release of odorant at low pH (as in the environment in the vicinity of odorant receptors). A C-terminal loop covers the binding cavity and this 'lid' may be opened by disruption of an array of acid-labile hydrogen bonds thus explaining reduced or no binding affinity at low pH.

  10. Characterizing the Aedes aegypti population in a Vietnamese village in preparation for a Wolbachia-based mosquito control strategy to eliminate dengue.

    Directory of Open Access Journals (Sweden)

    Jason A L Jeffery

    Full Text Available BACKGROUND: A life-shortening strain of the obligate intracellular bacteria Wolbachia, called wMelPop, is seen as a promising new tool for the control of Aedes aegypti. However, developing a vector control strategy based on the release of mosquitoes transinfected with wMelPop requires detailed knowledge of the demographics of the target population. METHODOLOGY/PRINCIPAL FINDINGS: In Tri Nguyen village (611 households on Hon Mieu Island in central Vietnam, we conducted nine quantitative entomologic surveys over 14 months to determine if Ae. aegypti populations were spatially and temporally homogenous, and to estimate population size. There was no obvious relationship between mosquito (larval, pupal or adult abundance and temperature and rainfall, and no area of the village supported consistently high numbers of mosquitoes. In almost all surveys, key premises produced high numbers of Ae. aegypti. However, these premises were not consistent between surveys. For an intervention based on a single release of wMelPop-infected Ae. aegypti, release ratios of infected to uninfected adult mosquitoes of all age classes are estimated to be 1.8-6.7ratio1 for gravid females (and similarly aged males or teneral adults, respectively. We calculated that adult female mosquito abundance in Tri Nguyen village could range from 1.1 to 43.3 individuals of all age classes per house. Thus, an intervention could require the release of 2-78 wMelPop-infected gravid females and similarly aged males per house, or 7-290 infected teneral female and male mosquitoes per house. CONCLUSIONS/SIGNIFICANCE: Given the variability we encountered, this study highlights the importance of multiple entomologic surveys when evaluating the spatial structure of a vector population or estimating population size. If a single release of wMelPop-infected Ae. aegypti were to occur when wild Ae. aegypti abundance was at its maximum, a preintervention control program would be necessary to ensure that

  11. Swarming mechanisms in the yellow fever mosquito: aggregation pheromones involved in the mating behavior of Aedes aegypti

    Science.gov (United States)

    Mosquitoes of various species mate in swarms comprised of tens to thousands flying males. Yet little information is known about mosquito swarming mechanism. Discovering chemical cues involved in mosquito biology leads to better adaptation of disease control interventions. In this study, we aimed ...

  12. A novel in vitro bioassay to explore the repellent effects of compounds against mosquito Aedes Aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Mosquitoes are vectors for many pathogens that can cause human diseases which can result in high rates of human morbidity and mortality at significant levels of transmission. Repellents play an important role in reducing mosquito bites and hence the risk of spread of mosquito borne diseases. Current...

  13. Localization and role of inward rectifier K(+) channels in Malpighian tubules of the yellow fever mosquito Aedes aegypti.

    Science.gov (United States)

    Piermarini, Peter M; Dunemann, Sonja M; Rouhier, Matthew F; Calkins, Travis L; Raphemot, Rene; Denton, Jerod S; Hine, Rebecca M; Beyenbach, Klaus W

    2015-12-01

    Malpighian tubules of adult female yellow fever mosquitoes Aedes aegypti express three inward rectifier K(+) (Kir) channel subunits: AeKir1, AeKir2B and AeKir3. Here we 1) elucidate the cellular and membrane localization of these three channels in the Malpighian tubules, and 2) characterize the effects of small molecule inhibitors of AeKir1 and AeKir2B channels (VU compounds) on the transepithelial secretion of fluid and electrolytes and the electrophysiology of isolated Malpighian tubules. Using subunit-specific antibodies, we found that AeKir1 and AeKir2B localize exclusively to the basolateral membranes of stellate cells and principal cells, respectively; AeKir3 localizes within intracellular compartments of both principal and stellate cells. In isolated tubules bathed in a Ringer solution containing 34 mM K(+), the peritubular application of VU590 (10 μM), a selective inhibitor of AeKir1, inhibited transepithelial fluid secretion 120 min later. The inhibition brings rates of transepithelial KCl and fluid secretion to 54% of the control without a change in transepithelial NaCl secretion. VU590 had no effect on the basolateral membrane voltage (Vbl) of principal cells, but it significantly reduced the cell input conductance (gin) to values 63% of the control within ∼90 min. In contrast, the peritubular application of VU625 (10 μM), an inhibitor of both AeKir1 and AeKir2B, started to inhibit transepithelial fluid secretion as early as 60 min later. At 120 min after treatment, VU625 was more efficacious than VU590, inhibiting transepithelial KCl and fluid secretion to ∼35% of the control without a change in transepithelial NaCl secretion. Moreover, VU625 caused the Vbl and gin of principal cells to respectively drop to values 62% and 56% of the control values within only ∼30 min. Comparing the effects of VU590 with those of VU625 allowed us to estimate that AeKir1 and AeKir2B respectively contribute to 46% and 20% of the transepithelial K

  14. Risk associated with the release of Wolbachia-infected Aedes aegypti mosquitoes into the environment in an effort to control Dengue.

    Directory of Open Access Journals (Sweden)

    Justine V Murray

    2016-03-01

    Full Text Available Background: In an effort to eliminate dengue, a successful technology was developed with the stable introduction of the obligate intracellular bacteria Wolbachia pipientis into the mosquito Aedes aegypti to reduce its ability to transmit dengue fever due to life shortening and inhibition of viral replication effects. An analysis of risk was required before considering release of the modified mosquito into the environment.Methods: Expert knowledge and a risk assessment framework was used to identify risk associated with the release of the modified mosquito. Individual and group expert elicitation was performed to identify potential hazards. A Bayesian network (BN was developed to capture the relationship between hazards and the likelihood of events occurring. Risk was calculated from the expert likelihood estimates populating the BN and the consequence estimates elicited from experts.Results: The risk model for ‘Don’t Achieve Release’ provided an estimated 46% likelihood that the release would not occur by a nominated time, but generated an overall risk rating of very low. The ability to obtain compliance had the greatest influence on the likelihood of release occurring. The risk model for ‘Cause More Harm’ provided a 12.5% likelihood that more harm would result from the release, but the overall risk was considered negligible. The efficacy of mosquito management had the most influence, with the perception that the threat of dengue fever had been eliminated, resulting in less household mosquito control, was scored as the highest ranked individual hazard (albeit low risk.Conclusions: The risk analysis was designed to incorporate the interacting complexity of hazards that may affect the release of the technology into the environment. The risk analysis was a small but important implementation phase in the success of this innovative research introducing a new technology to combat dengue transmission in the environment.

  15. Spectral and HRTEM analyses of Annona muricata leaf extract mediated silver nanoparticles and its Larvicidal efficacy against three mosquito vectors Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti.

    Science.gov (United States)

    Santhosh, Shanthi Bhupathi; Ragavendran, Chinnasamy; Natarajan, Devarajan

    2015-12-01

    Mosquitoes transmit various diseases which mainly affect the human beings and every year cause millions of deaths globally. Currently available chemical and synthetic mosquitocidal agents pose severe side effects, pollute the environment vigorously, and become resistance. There is an urgent need to identify and develop the cost effective, compatible and eco-friendly product for mosquito control. The present study was aimed to find out the larvicidal potential of aqueous crude extract and green synthesized silver nanoparticles (AgNPs) from Annona muricata leaves were tested against fourth instar larvae of three important mosquitoes i.e. Anopheles stephensi, Culex quinquefasciatus, and Aedes aegypti using different concentrations of AgNPs (10, 20, 30, 40 and 50 ppm) and the aqueous leaf extract (100, 200, 300, 400, and 500 ppm) for 24 and 48 h. The maximum mortality was noticed in AgNPs than aqueous leaf extract of A. muricata against tested mosquitoes with least LC50 values of 37.70, 31.29, and 20.65 ppm (24h) and 546.7, 516.2, and 618.4 ppm (48 h), respectively. All tested concentrations of AgNps exhibited 100% mortality in A. aegypti larvae at 48 hour observation. In addition, the plant mediated AgNPs were characterized by UV-vis spectrum, Fourier transform infrared spectroscopy, particle size analyser, X-ray diffraction, high resonance transmission electron microscopy, and energy-dispersive X-ray spectroscopy analysis for confirmation of nanoparticle synthesis. Based on the findings of the study suggests that the use of A. muricata plant mediated AgNPs can act as an alternate insecticidal agents for controlling target mosquitoes. PMID:26410042

  16. The effects of climate change and globalization on mosquito vectors: evidence from Jeju Island, South Korea on the potential for Asian tiger mosquito (Aedes albopictus influxes and survival from Vietnam rather than Japan.

    Directory of Open Access Journals (Sweden)

    Su Hyun Lee

    Full Text Available BACKGROUND: Climate change affects the survival and transmission of arthropod vectors as well as the development rates of vector-borne pathogens. Increased international travel is also an important factor in the spread of vector-borne diseases (VBDs such as dengue, West Nile, yellow fever, chikungunya, and malaria. Dengue is the most important vector-borne viral disease. An estimated 2.5 billion people are at risk of infection in the world and there are approximately 50 million dengue infections and an estimated 500,000 individuals are hospitalized with dengue haemorrhagic fever annually. The Asian tiger mosquito (Aedes albopictus is one of the vectors of dengue virus, and populations already exist on Jeju Island, South Korea. Currently, colder winter temperatures kill off Asian tiger mosquito populations and there is no evidence of the mosquitos being vectors for the dengue virus in this location. However, dengue virus-bearing mosquito vectors can inflow to Jeju Island from endemic area such as Vietnam by increased international travel, and this mosquito vector's survival during colder winter months will likely occur due to the effects of climate change. METHODS AND RESULTS: In this section, we show the geographical distribution of medically important mosquito vectors such as Ae. albopictus, a vector of both dengue and chikungunya viruses; Culex pipiens, a vector of West Nile virus; and Anopheles sinensis, a vector of Plasmodium vivax, within Jeju Island, South Korea. We found a significant association between the mean temperature, amount of precipitation, and density of mosquitoes. The phylogenetic analyses show that an Ae. albopictus, collected in southern area of Jeju Island, was identical to specimens found in Ho Chi Minh, Vietnam, and not Nagasaki, Japan. CONCLUSION: Our results suggest that mosquito vectors or virus-bearing vectors can transmit from epidemic regions of Southeast Asia to Jeju Island and can survive during colder winter

  17. Distribution and seasonality of vertically transmitted dengue viruses in Aedes mosquitoes in arid and semi-arid areas of Rajasthan, India

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    Bennet Angel

    2008-02-01

    Full Text Available Background & objectives: Transovarial transmission of dengue virus is a crucial etiological phenomenon responsible for persistence of virus during inter-epidemic period of the disease. Distribution and seasonality of this phenomenon in disease endemic areas may contribute to explain emergence of dengue and its subsequent prevention. The study on seasonal and area distribution of transovarial transmission of dengue virus in Aedes aegypti, Ae. albopictus and Ae. vittatus has been made in desert and non-desert districts of Rajasthan, India from 2006 to 2007. The observations revealed role of different Aedes species in transmission and retention of dengue virus.Methods: The larvae of Ae. aegypti, Ae. albopictus and Ae. vittatus were collected during each of the study seasons from rural and urban areas of three districts—Jodhpur, Jaipur and Kota. The larvae were collected from domestic and peri-domestic containers and from tree holes of peri-urban foci such as gardens and parks and were reared into adults in the laboratory at room temperature. The laboratory reared adults were subjected to Indirect fluorescence antibody test (IFAT. The laboratory-reared adult mosquitoes showing positive IFA were treated as the sample showing vertically transmitted dengue virus.Results: Pooled data for all the four seasons revealed maximum (15.7% mosquito infectivity in Ae. albopictus followed by Ae. aegypti (12.6% in Jodhpur district. In Jaipur district, Ae. vittatus showed highest infection (20% of vertically transmitted virus followed by Ae. albopictus (18.7% and least in Ae. aegypti (13.3%. In Kota district, pooled data for all the four seasons showed maximum vertical infection of mosquitoes in Ae. albopictus (14.2%.Interpretation & conclusion: Transovarial transmission of dengue virus by available vector species in a dengue endemic setting could be the key etiological phenomenon responsible for re-emergence of the disease from inter-epidemic to epidemic phase

  18. Correlating Remote Sensing Data with the Abundance of Pupae of the Dengue Virus Mosquito Vector, Aedes aegypti, in Central Mexico

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    Max J. Moreno-Madriñán

    2014-05-01

    Full Text Available Using a geographic transect in Central Mexico, with an elevation/climate gradient, but uniformity in socio-economic conditions among study sites, this study evaluates the applicability of three widely-used remote sensing (RS products to link weather conditions with the local abundance of the dengue virus mosquito vector, Aedes aegypti (Ae. aegypti. Field-derived entomological measures included estimates for the percentage of premises with the presence of Ae. aegypti pupae and the abundance of Ae. aegypti pupae per premises. Data on mosquito abundance from field surveys were matched with RS data and analyzed for correlation. Daily daytime and nighttime land surface temperature (LST values were obtained from Moderate Resolution Imaging Spectroradiometer (MODIS/Aqua cloud-free images within the four weeks preceding the field survey. Tropical Rainfall Measuring Mission (TRMM-estimated rainfall accumulation was calculated for the four weeks preceding the field survey. Elevation was estimated through a digital elevation model (DEM. Strong correlations were found between mosquito abundance and RS-derived night LST, elevation and rainfall along the elevation/climate gradient. These findings show that RS data can be used to predict Ae. aegypti abundance, but further studies are needed to define the climatic and socio-economic conditions under which the correlations observed herein can be assumed to apply.

  19. 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

    Anopheles gambiae orthologue. In Aedes aegypti, the dsx gene is sex-specifically regulated and encodes two female-specific and one male-specific isoforms, all sharing a doublesex/mab-3 (DM domain-containing N-terminus and different C-termini. The sex-specific regulation is based on a combination of exon skipping, 5' alternative splice site choice and, most likely, alternative polyadenylation. Interestingly, when the Aeadsx gene is compared to the Anopheles dsx ortholog, there are differences in the in silico predicted default and regulated sex-specific splicing events, which suggests that the upstream regulators either are different or act in a slightly different manner. Furthermore, this study is a premise for the future development of transgenic sexing strains in mosquitoes useful for sterile insect technique (SIT programs.

  20. 伊蚊诱捕器监测法在社区蚊媒监测中的应用%The application of Aedes traps for the mosquito monitoring in community

    Institute of Scientific and Technical Information of China (English)

    李美青; 俞守义; 刘彬; 罗雷; 吴辉绪; 刘颖; 邓旭林; 程燎原; 胡贵方; 陈清

    2012-01-01

    Objective To study the relationship between Aedes traps monitoring index and the traditional mosquito monitoring index, and climatic factors on the effect of the density of Aedes. Methods The density of the mosquito was monitored routinely with the Aedes traps for 11 months in a community of the Haizhu district in Guangzhou. We had done the correlation and regression analysis on Aedes traps monitoring index and traditional index. Regression analysis was also done for climate factors (temperature and humidity) and the density of Aedes. Results There is a correlation between Aedes traps monitoring index (Mosquito-trap positive index,Oviposition index,Mosquito and oviposition positive index) and traditional index(r=0.758,P=0.007;r=0.667,P=0.025;r=0.758,P=0.007) ,and the regression equation is Y=1.045+ 0.677a-0.590b, where "Y" is the Breteau index, "a" is Mosquito-trap positive index, and "b" is Oviposition index. The regression equation of climate factor and the density of mosquito is Y=-18.358+1.297a, where "Y" is the total number of Aedes albopictus, and "a" is temperature. Another regression equation of climate factor and the density of mosquito is Y=-702.837+47.035a, where "Y" is the total number of mosquito eggs, and "a" is temperature. Conclusion The close relationship between Aedes traps monitoring index and traditional index demonstrates that Aedes traps monitoring has strong credibility, and the climate factor plays an important role in the density of mosquito.%目的 探讨伊蚊诱捕器监测指标与传统蚊媒监测指标之间的关系,并分析气候因素对伊蚊密度的影响.方法 利用伊蚊诱捕器在广州市海珠区某社区对蚊媒密度进行为期11个月的常规监测.对伊蚊诱捕器监测指标与传统指标进行相关回归分析,并对气候因素(温度、湿度)与伊蚊密度进行回归分析.结果 伊蚊诱捕器监测指标诱蚊指数、诱卵指数、诱蚊诱卵指数与传统指标(布雷图

  1. Direct sequencing and expression analysis of a large number of miRNAs in Aedes aegypti and a multi-species survey of novel mosquito miRNAs

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    Liang Shaohui

    2009-12-01

    Full Text Available Abstract Background MicroRNAs (miRNAs are a novel class of gene regulators whose biogenesis involves hairpin structures called precursor miRNAs, or pre-miRNAs. A pre-miRNA is processed to make a miRNA:miRNA* duplex, which is then separated to generate a mature miRNA and a miRNA*. The mature miRNAs play key regulatory roles during embryonic development as well as other cellular processes. They are also implicated in control of viral infection as well as innate immunity. Direct experimental evidence for mosquito miRNAs has been recently reported in anopheline mosquitoes based on small-scale cloning efforts. Results We obtained approximately 130, 000 small RNA sequences from the yellow fever mosquito, Aedes aegypti, by 454 sequencing of samples that were isolated from mixed-age embryos and midguts from sugar-fed and blood-fed females, respectively. We also performed bioinformatics analysis on the Ae. aegypti genome assembly to identify evidence for additional miRNAs. The combination of these approaches uncovered 98 different pre-miRNAs in Ae. aegypti which could produce 86 distinct miRNAs. Thirteen miRNAs, including eight novel miRNAs identified in this study, are currently only found in mosquitoes. We also identified five potential revisions to previously annotated miRNAs at the miRNA termini, two cases of highly abundant miRNA* sequences, 14 miRNA clusters, and 17 cases where more than one pre-miRNA hairpin produces the same or highly similar mature miRNAs. A number of miRNAs showed higher levels in midgut from blood-fed female than that from sugar-fed female, which was confirmed by northern blots on two of these miRNAs. Northern blots also revealed several miRNAs that showed stage-specific expression. Detailed expression analysis of eight of the 13 mosquito-specific miRNAs in four divergent mosquito genera identified cases of clearly conserved expression patterns and obvious differences. Four of the 13 miRNAs are specific to certain lineage

  2. Creams formulated with Ocimum gratissimum L. and Lantana camara L. crude extracts and fractions as mosquito repellents against Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Keziah, Ezeike Amarachi; Nukenine, Elias Nchiwan; Danga, Simon Pierre Yinyang; Younoussa, Lame; Esimone, Charles Okechukwu

    2015-01-01

    Mosquitoes are the most deadly vectors of parasites that cause diseases such as malaria, yellow fever, and filariasis. In view of the recent increased interest in developing plant origin insecticides as an alternative to chemical insecticides, the objective of this study was to determine the repellent activity of creams formulated with methanol crude extract (MCE), hexane fraction (HF), and ethyl acetate fractions (EAFs) of Ocimum gratissimum and Lantana camara leaves in single and combined actions against female Aedes aegypti. Evaluation was carried out in the net cages (30 by 30 by 30 cm) containing 60 blood-starved female mosquitoes each and were assayed in the laboratory condition following World Health Organization 2009 protocol. All formulations (single and mixture) were applied at 2, 4, 6, and 8 mg/cm(2) in the exposed area of human hands. Only acetone + white soft paraffin served as negative control and odomos (12% DEET) as positive control. All the formulations presented good protection against mosquito bites without any allergic reaction by the human volunteers. The repellent activity was dependent on the strength of the extracts and fractions. Among the tested formulations, the maximum protection time was observed in MCE (120 min) and EAF (150 min) of O. gratissimum; MCE:MCE (150 min) and HF:HF (120 min) mixtures of both plants. In addition, MCE:MCE and HF:HF mixtures from both plants showed possible synergistic effect. From the results, the combination of O. gratissimum and L. camara to formulate natural mosquito repellent using small amount of extracts can be encouraging to be an alternative to conventional DEET. PMID:25881633

  3. The best time to have sex: mating behaviour and effect of daylight time on male sexual competitiveness in the Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Benelli, Giovanni

    2015-03-01

    Aedes albopictus is the most invasive mosquito worldwide and works as a vector for many important pathogens. Control tools rely to chemical treatments against larvae, indoor residual spraying and insecticide-treated bed nets. Recently, huge efforts have been carried out to propose new eco-friendly alternatives, such as evaluation of plant-borne compounds and sterile insect technique (SIT) programs. Success of SIT is dependent to the ability of sterile males to compete for mates with wild ones. Little is still known about mating behaviour of Aedes males. Most of the studies focus on comparisons of insemination ability in sterilised and wild males, while behavioural analyses of mating behaviour are lacking. Here, I quantified the courtship and mating behaviour of A. albopictus and evaluated how daylight hours affect male mating behaviour and success. A. albopictus males chased females facing them frontally, from behind, or from a lateral side. If the female allowed genital contact, copulation followed. Otherwise, females performed rejection kicks and/or flew away. Thirty-seven percent of males obtained a successful copulation (i.e. sperm transfer occurs), lasting 63 ± 4 s. Unsuccessful copulation (20 % of males) had shorter duration (18 ± 1 s). Successful copulations followed longer male courtships (39 ± 3 s), over courtships preceding unsuccessful copulation (20 ± 2 s) or male's rejection (22 ± 2 s). After copulation, the male rested 7 ± 0.4 s close to the female, then move off. In a semi-natural environment, male mating success was lower in early afternoon, over morning and late afternoon. However, little differences in courtship duration over daylight periods were found. This study adds knowledge to the reproductive behaviour of A. albopictus, which can be used to perform comparisons among courtship and mating ethograms from different mosquito species and strains, allowing monitoring and optimisation of mass rearing quality over time in SIT programs. PMID

  4. The Importance of Interspecific Interactions on the Present Range of the Invasive Mosquito Aedes albopictus (Diptera: Culicidae) and Persistence of Resident Container Species in the United States.

    Science.gov (United States)

    Fader, Joseph E

    2016-09-01

    Aedes albopictus (Skuse) established in the United States over 30 yr ago and quickly spread throughout the entire eastern half of the country. It has recently spread into western regions and projected climate change scenarios suggest continued expansion to the west and north. Aedes albopictus has had major impacts on, and been impacted by, a diverse array of resident mosquito species. Laying eggs at the edges of small, water-holding containers, hatched larvae develop within these containers feeding on detritus-based resources. Under limited resource conditions, Ae. albopictus has been shown to be a superior competitor to essentially all native and resident species in the United States. Adult males also mate interspecifically with at least one resident species with significant negative impacts on reproductive output for susceptible females. Despite these strong interference effects on sympatric species, competitor outcomes have been highly variable, ranging from outright local exclusion by Ae. albopictus, to apparent exclusion of Ae. albopictus in the presence of the same species. Context-dependent mechanisms that alter the relative strengths of inter- and intraspecific competition, as well as rapid evolution of satyrization-resistant females, may help explain these patterns of variable coexistence. Although there is a large body of research on interspecific interactions of Ae. albopictus in the United States, there remain substantial gaps in our understanding of the most important species interactions. Addressing these gaps is important in predicting the future distribution of this species and understanding consequences for resident species, including humans, that interact with this highly invasive mosquito. PMID:27354436

  5. Cloning and sequencing of the blood meal-induced late trypsin gene from the mosquito Aedes aegypti and characterization of the upstream regulatory region.

    Science.gov (United States)

    Barillas-Mury, C; Wells, M A

    1993-01-01

    A 4.1 kb genomic clone of the late trypsin gene from the mosquito Aedes aegypti was isolated, mapped and subcloned. A 1.6 kb subclone, corresponding to 1.1 kb of upstream regulatory region and 0.5 kb of coding region, was sequenced. The gene has no introns within the coding region. The 5' end of the mature mRNA was mapped using primer extension analysis. A TATA box consensus sequence (TATAAA) was found at position -31 from the 5' end of the mature mRNA. A cluster of five repeat sequences homologous to the yeast GCN4 DNA binding site was found within 200 nucleotides upstream of the cap site. GCN4 is required for derepression mediated control of general amino acid biosynthesis in response to amino acid starvation in yeast. It activates the transcription of at least twenty different genes coding for enzymes involved in amino acid biosynthesis. The presence of this cluster of consensus sequences suggests that a protein similar to GCN4 might regulate expression of the late trypsin gene in the mosquito. Southern blot analysis of genomic DNA indicates that late trypsin is a single copy gene. PMID:9087537

  6. Structure, expression, and hormonal control of genes from the mosquito, Aedes aegypti, which encode proteins similar to the vitelline membrane proteins of Drosophila melanogaster.

    Science.gov (United States)

    Lin, Y; Hamblin, M T; Edwards, M J; Barillas-Mury, C; Kanost, M R; Knipple, D C; Wolfner, M F; Hagedorn, H H

    1993-02-01

    Genomic and cDNA clones of a gene expressed after a blood meal in the mosquito, Aedes aegypti, were identified as having significant similarity to the vitelline membrane protein genes of Drosophila melanogaster. The predicted protein had unusually high contents of alanine, histidine, and proline and contained a region of hydrophobic amino acids that was highly conserved in the predicted protein of the D. melanogaster vitelline membrane protein genes. The 15a gene was expressed from 5 to 40 hr after a blood meal. It was expressed only in the follicle cells of the ovary, particularly in the cells surrounding the oocyte. The 15a gene was expressed in ovaries of the blood-fed, decapitated female in response to an injection of 20-hydroxyecdysone, and in ovaries from non-blood-fed females incubated with the hormone, even in the presence of cycloheximide. A second gene, with weaker homology to 15a, is presumably another member of a family of related genes, as is the case with D. melanogaster vitelline membrane protein genes. This second gene contained a coding sequence similar to a decapeptide recently isolated from mosquito ovaries as an "oostatic factor" (Borovsky et al., FASEB J. 4, 3015-3020, 1990). PMID:8432405

  7. In vitro Mosquito Larvicidal Activity of Marine Algae Against the Human Vectors, Culex quinquefasciatus (Say and Aedes aegypti (Linnaeus (Diptera: Culicidae

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    Akbar Idhayadhulla

    2011-01-01

    Full Text Available A total of twenty marine algae were collected from the rocky intertidal and subtidal regions of the southwest coast of India and extracted in methanol. The extracts were evaluated for larvicidal activity against the second and third instar larvae of the human vector mosquito Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae. Analysis on the activity profile of the above marine algae indicated that the early stage larvae were very sensitive to seven seaweed extracts that had been tested. Among the seven marine algae, Lobophora variegata was highly potential, showing LD50 value of 70.38 and 79.43 g mL-1 on the 2nd instar larvae of A. aegypti and C. quinquefasciatus respectively. The rank of larvicidal potency in highly active algae in the descending order is as follows: Lobophora variegata (Dictyotaceae>Spatoglossum asperum (Dictyotaceae>Stoechospermum marginatum (Dictyotaceae>Sargassum wightii (Sargassaceae >Acrosiphonia orientalis (Acrosiphoniaceae>Centroceras clavulatum (Ceramiacea>Padina tetrastromatica (Dictyotaceae. This is the first report that envisaged the mosquito larvicidal efficacy of L. variegata from the Indian coast. Therefore, this marine alga could be recognized as a potential resource of natural insecticide and can be developed to replace synthetic insecticides in future.

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

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-03-01

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

  9. Container productivity, daily survival rates and dispersal of Aedes aegypti mosquitoes in a high income dengue epidemic neighbourhood of Rio de Janeiro: presumed influence of differential urban structure on mosquito biology

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    Mariana Rocha David

    2009-09-01

    Full Text Available Different urban structures might affect the life history parameters of Aedes aegypti and, consequently, dengue transmission. Container productivity, probability of daily survival (PDS and dispersal rates were estimated for mosquito populations in a high income neighbourhood of Rio de Janeiro. Results were contrasted with those previously found in a suburban district, as well as those recorded in a slum. After inspecting 1,041 premises, domestic drains and discarded plastic pots were identified as the most productive containers, collectively holding up to 80% of the total pupae. In addition, three cohorts of dust-marked Ae. aegypti females were released and recaptured daily using BGS-Traps, sticky ovitraps and backpack aspirators in 50 randomly selected houses; recapture rate ranged from 5-12.2% within cohorts. PDS was determined by two models and ranged from 0.607-0.704 (exponential model and 0.659-0.721 (non-linear model, respectively. Mean distance travelled varied from 57-122 m, with a maximum dispersal of 263 m. Overall, lower infestation indexes and adult female survival were observed in the high income neighbourhood, suggesting a lower dengue transmission risk in comparison to the suburban area and the slum. Since results show that urban structure can influence mosquito biology, specific control strategies might be used in order to achieve cost-effective Ae. aegypti control.

  10. Comparative host feeding patterns of the Asian tiger mosquito, Aedes albopictus, in urban and suburban Northeastern USA and implications for disease transmission.

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    Ary Faraji

    2014-08-01

    Full Text Available Aedes albopictus is an invasive species which continues expanding its geographic range and involvement in mosquito-borne diseases such as chikungunya and dengue. Host selection patterns by invasive mosquitoes are critically important because they increase endemic disease transmission and drive outbreaks of exotic pathogens. Traditionally, Ae. albopictus has been characterized as an opportunistic feeder, primarily feeding on mammalian hosts but occasionally acquiring blood from avian sources as well. However, limited information is available on their feeding patterns in temperate regions of their expanded range. Because of the increasing expansion and abundance of Ae. albopictus and the escalating diagnoses of exotic pathogens in travelers returning from endemic areas, we investigated the host feeding patterns of this species in newly invaded areas to further shed light on its role in disease ecology and assess the public health threat of an exotic arbovirus outbreak.We identified the vertebrate source of 165 blood meals in Ae. albopictus collected between 2008 and 2011 from urban and suburban areas in northeastern USA. We used a network of Biogents Sentinel traps, which enhance Ae. albopictus capture counts, to conduct our collections of blooded mosquitoes. We also analyzed blooded Culex mosquitoes collected alongside Ae. albopictus in order to examine the composition of the community of blood sources. We found no evidence of bias since as expected Culex blood meals were predominantly from birds (n = 149, 93.7% with only a small proportion feeding on mammals (n = 10, 6.3%. In contrast, Aedes albopictus fed exclusively on mammalian hosts with over 90% of their blood meals derived from humans (n = 96, 58.2% and domesticated pets (n = 38, 23.0% cats; and n = 24, 14.6% dogs. Aedes albopictus fed from humans significantly more often in suburban than in urban areas (χ(2, p = 0.004 and cat-derived blood meals were greater in urban habitats (χ(2, p

  11. Optimal strategies for Aedes aegypti mosquito control via transgenic and sterile insect techniques: endemics and emerging outbreaks

    OpenAIRE

    Seirin Lee, S.; Baker, R. E.; Gaffney, E.A.; White, S. M.

    2013-01-01

    The invasion of pest insects often changes or destroys a native ecosystem, and can result in food shortages and disease endemics. Issues such as the environmental effects of chemical control methods, the economic burden of maintaining control strategies and the risk of pest resistance still remain, and mosquito-borne diseases such as malaria and dengue fever prevail in many countries, infecting over 100 million worldwide in 2010. One environmentally friendly method for mosquito control is the...

  12. Investigating the Potential Range Expansion of the Vector Mosquito Aedes Aegypti in Mexico with NASA Earth Science Remote Sensing Results

    Science.gov (United States)

    Estes, Sue M.

    2011-01-01

    Dengue (Breakbone) fever is caused by one of four viruses carried by mosquitoes in tropical and subtropical areas. Cases have increased dramatically in the past few decades; there are currently approximately 100 million infections annually around the globe. Our project will integrate environmental observations, including weather, land use, vegetation type, amount and greenness, soil moisture, and mosquito populations with investigations of the human dynamics of the system via household surveys.

  13. Nanoparticles in the fight against mosquito-borne diseases: bioactivity of Bruguiera cylindrica-synthesized nanoparticles against dengue virus DEN-2 (in vitro) and its mosquito vector Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Murugan, Kadarkarai; Dinesh, Devakumar; Paulpandi, Manickam; Althbyani, Abdulaziz Dakhellah Meqbel; Subramaniam, Jayapal; Madhiyazhagan, Pari; Wang, Lan; Suresh, Udaiyan; Kumar, Palanisamy Mahesh; Mohan, Jagathish; Rajaganesh, Rajapandian; Wei, Hui; Kalimuthu, Kandasamy; Parajulee, Megha N; Mehlhorn, Heinz; Benelli, Giovanni

    2015-12-01

    Mosquitoes are blood-feeding insects serving as the most important vectors for spreading human pathogens and parasites. Dengue is a viral disease mainly vectored through the bite of Aedes mosquitoes. Its transmission has recently increased in urban and semi-urban areas of tropical and subtropical regions worldwide, becoming a major international public health concern. There is no specific treatment for dengue. Its prevention and control solely depend on effective vector control measures. Mangrove plants have been used in Indian traditional medicine for a wide array of purposes. In this research, we proposed a method for biosynthesis of antiviral and mosquitocidal silver nanoparticles (AgNP) using the aqueous extract of Bruguiera cylindrica leaves. AgNP were characterized using a variety of biophysical analyses, including UV-visible spectrophotometry, Fourier-transform infrared spectroscopy, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. Bruguiera cilyndrica aqueous extract and green-synthesized AgNP were tested against the primary dengue vector Aedes aegypti. AgNP were the most effective. LC50 values ranged from 8.93 ppm (larva I) to 30.69 ppm (pupa). In vitro experiments showed that 30 μg/ml of AgNP significantly inhibited the production of dengue viral envelope (E) protein in vero cells and downregulated the expression of dengue viral E gene. Concerning nontarget effects, we observed that the predation efficiency of Carassius auratus against A. aegypti was not affected by exposure at sublethal doses of AgNP. Predation in the control was 71.81 % (larva II) and 50.43 % (larva III), while in an AgNP-treated environment, predation was boosted to 90.25 and 76.81 %, respectively. Overall, this study highlights the concrete potential of green-synthesized AgNP in the fight against dengue virus. Furthermore, B. cylindrica-synthesized AgNP can be employed at low doses to reduce larval and pupal population of A. aegypti, without detrimental

  14. In vitro Mosquito Larvicidal Activity of Marine Algae Against the Human Vectors, Culex quinquefasciatus (Say) and Aedes aegypti (Linnaeus) (Diptera: Culicidae)

    OpenAIRE

    Akbar Idhayadhulla; Joseph Selvin; Nooruddin Thajuddin; Radhakrishnan Surendra Kumar; Aseer Manilal; Sugathan Sujith

    2011-01-01

    A total of twenty marine algae were collected from the rocky intertidal and subtidal regions of the southwest coast of India and extracted in methanol. The extracts were evaluated for larvicidal activity against the second and third instar larvae of the human vector mosquito Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae). Analysis on the activity profile of the above marine algae indicated that the early stage larvae were very sensitive to seven seaweed extracts that had been t...

  15. Performance of the plant-based repellent TT-4302 against mosquitoes in the laboratory and field and comparative efficacy to 16 mosquito repellents against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Bissinger, B W; Schmidt, J P; Owens, J J; Mitchell, S M; Kennedy, M K

    2014-03-01

    Repellent efficacy of the plant-based repellent, TT-4302 (5% geraniol), was compared with 16 other products in laboratory arm-in-cage trials against Aedes aegypti (L). Eight repellents (Badger, BioUD, Burt's bees, California Baby, Cutter Natural, EcoSMART, Herbal Armor, and SkinSmart) exhibited a mean repellency below 90% to Ae. aegypti at 0.5 h after application. Three repellents (Buzz Away Extreme, Cutter Advanced, and OFF! Botanicals lotion) fell below 90% repellency 1.5 h after application. TT-4302 exhibited 94.7% repellency 5 h posttreatment, which was a longer duration than any of the other repellents tested. The positive control, 15% DEET (OFF! Active), was repellent for 3 h before activity dropped below 90%. Additional arm-in-cage trials comparing TT-4302 with 15% DEET were carried out against Anopheles quadrimaculatus Say. At 6 h after treatment, TT-4302 provided 95.2% repellency while DEET exhibited 72.2%. In North Carolina field trials, TT-4302 provided 100% repellency 5 h after application against Aedes albopictus Skuse while DEET provided 77.6% repellency. These results demonstrate that TT-4302 is an efficacious plant-based repellent that provides an extended duration of protection compared with many other commercially available products. PMID:24724289

  16. Transcriptome Profiling and Genetic Study Reveal Amplified Carboxylesterase Genes Implicated in Temephos Resistance, in the Asian Tiger Mosquito Aedes albopictus.

    OpenAIRE

    Linda Grigoraki; Jacques Lagnel; Ilias Kioulos; Anastasia Kampouraki; Evangelia Morou; Pierrick Labbé; Mylene Weill; John Vontas

    2015-01-01

    Background The control of Aedes albopictus, a major vector for viral diseases, such as dengue fever and chikungunya, has been largely reliant on the use of the larvicide temephos for many decades. This insecticide remains a primary control tool for several countries and it is a potential reliable reserve, for emergency epidemics or new invasion cases, in regions such as Europe which have banned its use. Resistance to temephos has been detected in some regions, but the mechanism responsible fo...

  17. Landmark-based geometric morphometric analysis of wing shape among certain species of Aedes mosquitoes in District Dehradun (Uttarakhand), India

    OpenAIRE

    Ritwik Mondal; Pemola Devi, N.; R.K. Jauhari

    2015-01-01

    Background & objectives: Insect wing morphology has been used in many studies to describe variations among species and populations using traditional morphometrics, and more recently geometric morphometrics. A landmark-based geometric morphometric analysis of the wings of three species of Aedes (Diptera: Culicidae), viz. Ae. aegypti, Ae. albopictus and Ae. pseudotaeniatus, at District Dehradun was conducted belling on the fact that it can provide insight into the population structure, ecology ...

  18. Studies on mosquitoes (Diptera: Culicidae and anthropic environment: 9- Synanthropy and epidemiological vector role of Aedes scapularis in South-Eastern Brazil

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    Oswaldo Paulo Forattini

    1995-06-01

    Full Text Available Behaviour comparisons of Aedes scapularis and Ae. serratus are presented. Results were obtained by sampling Aedes adult mosquitoes at several places in the rural anthropic environment in the Ribeira Valley region of S. Paulo State, Brazil. Aedes dominance was shared by those two species, but Ae. scapularis Sshowed a clear tendency to frequent the modified environment, while Ae. serratus was to be found in the more preserved ones, here represented by the vestigial patchy forests. Regarding the open cultivated land and the dwelling environments, Ae. scapularis preponderates. Considering the regional developmental phases, this mosquito showed a remarkable increase in the modified environment differently from Ae. serratus that underwent a considerable decrease in migrating from the forest to the anthropic environment. As a consequence of these results it is reasonable to conclude that Ae. scapularis may be considered as an epidemiologically efficient vector and that it quite probably played this role in the Rocio encephalitis and other arbovirus epidemics.Relatam-se os resultados de coletas regulares de adultos de culicídeos Aedes, levadas a efeito em ambiente antrópico do Vale do Ribeira, SP, Brasil, ao longo do período de agosto de 1992 a dezembro de 1993. As coletas foram realizadas em várias áreas correspondentes a matas residuais, a ambiente aberto cultivado e a meio domiciliar. A dominância dividiu-se entre Ae. scapularis e Ae. serratus, porém não de maneira equivalente para as diversas áreas pesquisadas. O primeiro revelou nítida tendência ao predomínio no ambiente artificial representado pela área aberta cultivada e pelo domicílio humano. Quanto ao segundo, evidenciou-se nítida preferência pelo meio das matas residuais. Considerando este como remanescente da primitiva cobertura florestal da área, os outros foram tidos como fase posteriormente desenvolvida em virtude da atividade humana. Assim procedendo, compararam-se as

  19. A Novel in vitro Bioassay to Explore the Repellent Effects of Compounds Against Mosquito Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Rehman, Junaid U; Tabanca, Nurhayat; Khan, Ikhlas A

    2016-01-01

    Mosquitoes are vectors for many pathogens resulting in many deaths of humans. Repellents play an important role in reducing mosquito bites and the spread of mosquito-borne diseases. Currently, Klun & Debboun (K & D) and human-arm-based bioassay systems are used to identify repellent properties of compounds, extracts, and essential oils. Risks involved with human-arm-based systems are allergic reactions and limited replicates. We are reporting an in vitro bioassay method “NCNPR repellent bioassay (NCNPR-RB)” that can closely simulate the results of the cloth patch bioassay system used to determine repellency against mosquitoes. The NCNPRRB method uses heat to attract mosquito and edible collagen sheets as an alternate to human skin. Multiple plant compounds with documented repellency were tested. DEET (N,N-diethyl-3-methylbenzamide) was used as a positive control. Treatments were prepared in EtOH and applied in dosages ranging from 0.011–1.5mg/cm2 to a 20-cm2 collagen sheet. The number of mosquitoes commencing to bite per probe was recorded visually for 1 min. The minimum effective dosage (mg/cm2) of compounds: DEET (0.021), carvacrol (0.011), thymol (0.013), undecanoic acid (0.023), thymol methyl ether (0.269), and 2-nonanone (>0.375 mg/cm2) determined in NCNPRRB were similar to those reported in literature using a cloth patch bioassay system. The NCNPR-RB can be used to screen compounds with reasonable reproducibility of the data at a faster rate than the cloth patch bioassay, which involves the use of human subjects. PMID:26590191

  20. Design and Testing of Novel Lethal Ovitrap to Reduce Populations of Aedes Mosquitoes: Community-Based Participatory Research between Industry, Academia and Communities in Peru and Thailand

    Science.gov (United States)

    Yukich, Josh; Soonthorndhada, Amara; Giron, Maziel; Apperson, Charles S.; Ponnusamy, Loganathan; Schal, Coby; Morrison, Amy C.; Keating, Joseph; Wesson, Dawn M.

    2016-01-01

    Background Dengue virus (and Chikungunya and Zika viruses) is transmitted by Aedes aegypti and Aedes albopictus mosquitoes and causes considerable human morbidity and mortality. As there is currently no vaccine or chemoprophylaxis to protect people from dengue virus infection, vector control is the only viable option for disease prevention. The purpose of this paper is to illustrate the design and placement process for an attractive lethal ovitrap to reduce vector populations and to describe lessons learned in the development of the trap. Methods This study was conducted in 2010 in Iquitos, Peru and Lopburi Province, Thailand and used an iterative community-based participatory approach to adjust design specifications of the trap, based on community members’ perceptions and feedback, entomological findings in the lab, and design and research team observations. Multiple focus group discussions (FGD) were held over a 6 month period, stratified by age, sex and motherhood status, to inform the design process. Trap testing transitioned from the lab to within households. Results Through an iterative process of working with specifications from the research team, findings from the laboratory testing, and feedback from FGD, the design team narrowed trap design options from 22 to 6. Comments from the FGD centered on safety for children and pets interacting with traps, durability, maintenance issues, and aesthetics. Testing in the laboratory involved releasing groups of 50 gravid Ae. aegypti in walk-in rooms and assessing what percentage were caught in traps of different colors, with different trap cover sizes, and placed under lighter or darker locations. Two final trap models were mocked up and tested in homes for a week; one model was the top choice in both Iquitos and Lopburi. Discussion The community-based participatory process was essential for the development of novel traps that provided effective vector control, but also met the needs and concerns of community

  1. Landmark-based geometric morphometric analysis of wing shape among certain species of Aedes mosquitoes in District Dehradun (Uttarakhand, India

    Directory of Open Access Journals (Sweden)

    Ritwik Mondal

    2015-01-01

    Interpretation & conclusion: It has been marked out that the geometric morphometrics utilizes powerful and comprehensive statistical procedures to analyze the shape differences of a morphological feature, assuming that the studied mosquitoes may represent different genotypes and probably come from one diverse gene pool.

  2. The genetic architecture of a complex trait: Resistance to multiple toxins produced by Bacillus thuringiensis israelensis in the dengue and yellow fever vector, the mosquito Aedes aegypti.

    Science.gov (United States)

    Bonin, Aurélie; Paris, Margot; Frérot, Hélène; Bianco, Erica; Tetreau, Guillaume; Després, Laurence

    2015-10-01

    The bacterial insecticide Bacillus thuringiensis subsp. israelensis (Bti) is an increasingly popular alternative to chemical insecticides for controlling mosquito populations. Because Bti toxicity relies on the action of four main toxins, resistance to Bti is very likely a complex phenotype involving several genes simultaneously. Dissecting the underlying genetic basis thus requires associating a quantitative measure of resistance to genetic variation at many loci in a segregating population. Here, we undertake this task using the dengue and yellow fever vector, the mosquito Aedes aegypti, as a study model. We conducted QTL (Quantitative Trait Locus) and admixture mapping analyses on two controlled crosses and on an artificial admixed population, respectively, all obtained from resistant and susceptible lab strains. We detected 16 QTL regions, among which four QTLs were revealed by different analysis methods. These four robust QTLs explained altogether 29.2% and 62.2% of the total phenotypic variance in the two QTL crosses, respectively. They also all showed a dominant mode of action. In addition, we found six loci showing statistical association with Bti resistance in the admixed population. Five of the supercontigs highlighted in this study contained candidate genes as suggested by their function, or by prior evidence from expression and/or outlier analyses. These genomic regions are thus good starting points for fine mapping of resistance to Bti or functional analyses aiming at identifying the underlying genes and mutations. Moreover, for the purpose of this work, we built the first Ae. aegypti genetic map based on markers associated with genes expressed in larvae. This genetic map harbors 229 SNP markers mapped across the three chromosomes for a total length of 311.9cM. It brought to light several assembly discrepancies with the reference genome, suggesting a high level of genome plasticity in Ae. aegypti. PMID:26238211

  3. Larvicidal activity and GC-MS analysis of flavonoids of Vitex negundo and Andrographis paniculata against two vector mosquitoes Anopheles stephensi and Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Keerti Gautam

    2013-08-01

    Full Text Available Background & objectives: Development of insect resistance to synthetic pesticides, high operational cost and environmental pollution have created the need for developing alternative approaches to control vector-borne diseases. In the present study, larvicidal activity of flavonoid extracts of different parts of Vitex negundo (Linnaeus and Andrographis paniculata (Nees have been studied against the late III or early IV instar larvae of Aedes aegypti and Anopheles stephensi (Liston. Methods: Flavonoids were extracted from different parts of the selected plants using standard method. Bioassay test was carried out by WHO method for determination of larvicidal activity against mosquitoes. Different compounds of the most active extract were identified by the gas chromatography-mass spectrometry (GC-MS analysis. Results: Flavonoid extract of whole aerial part of A. paniculata was found to be inactive against the selected larvae of Ae. aegypti even at the concentration of 600 ppm, whereas it caused 70% mortality in An. stephensi at the concentration of 200 ppm. Flavonoid extract of flower-buds produced highest mortality (100% at the concentration of 600 ppm for the late III or early IV instar larvae of Ae. aegypti and at the concentration of 200 ppm for the larvae of An. stephensi. GC-MS analysis of the most active flavonoid extract from flower-buds of Vitex showed 81 peaks. Phenol (26.83% area, naphthalene (4.95% area, 2,3-dihydrobenzofuran (6.79% area, Phenol-2,4-Bis (1,1-dimethyl (4.49% area, flavones 4'-OH,5-OH,7-di-O-glucoside (0.25% area and 5-hydroxy- 3,6,7,3',4'-pentamethoxy flavones (0.80% area were present in major amount. Conclusion: Flavonoid extracts from different parts of two selected plants possess larvicidal activity against two selected mosquito species, hence, could be utilized for developing flavonoid-based, ecofriendly insecticide as an alternative to synthetic insecticides.

  4. Mapping of zones potentially occupied by Aedes vexans and Culex poicilipes mosquitoes, the main vectors of Rift Valley fever in Senegal

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    Yves M. Tourre

    2008-11-01

    Full Text Available A necessary condition for Rift Valley fever (RVF emergence is the presence of Aedes (Aedimorphus vexans and Culex (Culex poicilipes mosquitoes carrying the arbovirus and responsible for the infection. This paper presents a detailed mapping in the Sahelian region of Senegal of zones potentially occupied by these mosquitoes (ZPOMs whose population density is directly linked to ecozones in the vicinity of small ponds. The vectors habitats and breeding sites have been characterized through an integrated approach combining remote sensing technology, geographical information systems, geographical positioning systems and field observations for proper geo-referencing. From five SPOT-5 images (~10 m spatial resolution with appropriate channels, a meridional composite transect of 290 x 60 km was first constructed at the height of the summer monsoon. Subsequent ZPOMs covered major ecozones from north to south with different hydrological environments and different patterns pond distributions. It was found that an overall area of 12,817 ha ± 10% (about 0.8% of the transect is occupied by ponds with an average ZPOM 17 times larger than this (212,813 ha ± 10% or about 14% of the transect. By comparing the very humid year of 2003 with 2006 which had just below normal rainfall, the ZPOMs inter-annual variability was analyzed in a sandy-clayey ecozone with an important hydrofossil riverbed within the Ferlo region of Senegal. Very probably contributing to an increased abundance of vectors by the end of August 2003, it was shown that the aggregate pond area was already about 22 times larger than in August 2006, corresponding to an approximately five times larger total ZPOM. The results show the importance of pin-pointing small ponds (sizes down to 0.1 ha and their geographical distribution in order to assess animal exposure to the RVF vectors.

  5. Effects of diapause and cold acclimation on egg ultrastructure: new insights into the cold hardiness mechanisms of the Asian tiger mosquito Aedes (Stegomyia) albopictus.

    Science.gov (United States)

    Kreß, Aljoscha; Kuch, Ulrich; Oehlmann, Jörg; Müller, Ruth

    2016-06-01

    The Asian tiger mosquito, Aedes albopictus (Diptera: Culicidae, SKUSE), is an important threat to public health due to its rapid spread and its potential as a vector. The eggs of Ae. albopictus are the most cold resistant life stage and thus, the cold hardiness of eggs is used to predict the future occurrence of the species in distribution models. However, the mechanism of cold hardiness has yet to be revealed. To address this question, we analyzed the layers of diapausing and cold acclimatized eggs of a temperate population of Ae. albopictus in a full factorial test design using transmission electron microscopy. We reviewed the hypotheses that a thickened wax layer or chorion is the cause of cold hardiness but found no evidence. As a result of the induced diapause, the thickness of the dark endochorion as a layer of high electron density and thus an assumed location for waxes was decreasing. We therefore hypothesized a qualitative alteration of the wax layer due to compaction. Cold acclimation was causing an increase in the thickness of the middle serosa cuticle indicating a detachment of serosa membrane from the endochorion as a potential adaptation strategy to isolate inoculating ice formations in the inter-membranous space. PMID:27232137

  6. Persistent Wolbachia and cultivable bacteria infection in the reproductive and somatic tissues of the mosquito vector Aedes albopictus.

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    Karima Zouache

    Full Text Available BACKGROUND: Commensal and symbiotic microbes have a considerable impact on the behavior of many arthropod hosts, including hematophagous species that transmit pathogens causing infectious diseases to human and animals. Little is known about the bacteria associated with mosquitoes other than the vectorized pathogens. This study investigated Wolbachia and cultivable bacteria that persist through generations in Ae. albopictus organs known to host transmitted arboviruses, such as dengue and chikungunya. METHODOLOGY/PRINCIPAL FINDINGS: We used culturing, diagnostic and quantitative PCR, as well as in situ hybridization, to detect and locate bacteria in whole individual mosquitoes and in dissected tissues. Wolbachia, cultivable bacteria of the genera Acinetobacter, Comamonas, Delftia and Pseudomonas co-occurred and persisted in the bodies of both males and females of Ae. albopictus initially collected in La Réunion during the chikungunya outbreak, and maintained as colonies in insectaries. In dissected tissues, Wolbachia and the cultivable Acinetobacter can be detected in the salivary glands. The other bacteria are commonly found in the gut. Quantitative PCR estimates suggest that Wolbachia densities are highest in ovaries, lower than those of Acinetobacter in the gut, and approximately equal to those of Acinetobacter in the salivary glands. Hybridization using specific fluorescent probes successfully localized Wolbachia in all germ cells, including the oocytes, and in the salivary glands, whereas the Acinetobacter hybridizing signal was mostly located in the foregut and in the anterior midgut. CONCLUSIONS/SIGNIFICANCE: Our results show that Proteobacteria are distributed in the somatic and reproductive tissues of mosquito where transmissible pathogens reside and replicate. This location may portend the coexistence of symbionts and pathogens, and thus the possibility that competition or cooperation phenomena may occur in the mosquito vector Ae

  7. Droplet Characterization and Penetration of an Ultra-Low Volume Mosquito Adulticide Spray Targeting the Asian Tiger Mosquito, Aedes albopictus, within Urban and Suburban Environments of Northeastern USA.

    Science.gov (United States)

    Faraji, Ary; Unlu, Isik; Crepeau, Taryn; Healy, Sean; Crans, Scott; Lizarraga, Griffith; Fonseca, Dina; Gaugler, Randy

    2016-01-01

    Adult control of Aedes albopictus via ultra-low volume is difficult because this species occurs primarily in peridomestic habitats where obstacles such as buildings and vegetation can disrupt spray plumes and droplet dispersion. We determined droplet penetration and characterization of a pyrethroid adulticide applied from the ground at mid (46.77 ml/ha) and maximum (93.53 ml/ha) label rates within cryptic habitats of urban and suburban environments. Droplets were collected from all habitats, with no significant differences detected between locations within the same application rate or collection method. No differences were detected in droplet densities (drops per mm2) between rates within urban environments, but more droplets were collected in urban (149.93 ± 11.07 SE) than suburban sites (114.37 ± 11.32) at the maximum label rate (P = 0.003). The excellent penetration of aerosols into cryptic habitats of an urban site was likely due to the shorter spray paths afforded by our network of roads and alleys. Mid label rates displayed similar droplet density values as maximum label rates in urban areas, indicating that lower rates may be used effectively to reduce costs, lessen non-target effects, and increase environmental stewardship. Advances in formulations and technology are driving changes in adulticide applications, leading to use of the minimum effective dose for maximum efficacy, precision, and accountability. PMID:27116103

  8. Droplet Characterization and Penetration of an Ultra-Low Volume Mosquito Adulticide Spray Targeting the Asian Tiger Mosquito, Aedes albopictus, within Urban and Suburban Environments of Northeastern USA

    Science.gov (United States)

    Faraji, Ary; Unlu, Isik; Crepeau, Taryn; Healy, Sean; Crans, Scott; Lizarraga, Griffith; Fonseca, Dina; Gaugler, Randy

    2016-01-01

    Adult control of Aedes albopictus via ultra-low volume is difficult because this species occurs primarily in peridomestic habitats where obstacles such as buildings and vegetation can disrupt spray plumes and droplet dispersion. We determined droplet penetration and characterization of a pyrethroid adulticide applied from the ground at mid (46.77 ml/ha) and maximum (93.53 ml/ha) label rates within cryptic habitats of urban and suburban environments. Droplets were collected from all habitats, with no significant differences detected between locations within the same application rate or collection method. No differences were detected in droplet densities (drops per mm2) between rates within urban environments, but more droplets were collected in urban (149.93 ± 11.07 SE) than suburban sites (114.37 ± 11.32) at the maximum label rate (P = 0.003). The excellent penetration of aerosols into cryptic habitats of an urban site was likely due to the shorter spray paths afforded by our network of roads and alleys. Mid label rates displayed similar droplet density values as maximum label rates in urban areas, indicating that lower rates may be used effectively to reduce costs, lessen non-target effects, and increase environmental stewardship. Advances in formulations and technology are driving changes in adulticide applications, leading to use of the minimum effective dose for maximum efficacy, precision, and accountability. PMID:27116103

  9. Evolutionary analysis of the kinesin light chain genes in the yellow fever mosquito Aedes aegypti: gene duplication as a source for novel early zygotic genes

    Directory of Open Access Journals (Sweden)

    Tu Zhijian

    2010-07-01

    Full Text Available Abstract Background The maternal zygotic transition marks the time at which transcription from the zygotic genome is initiated and a subset of maternal RNAs are progressively degraded in the developing embryo. A number of early zygotic genes have been identified in Drosophila melanogaster and comparisons to sequenced mosquito genomes suggest that some of these early zygotic genes such as bottleneck are fast-evolving or subject to turnover in dipteran insects. One objective of this study is to identify early zygotic genes from the yellow fever mosquito Aedes aegypti to study their evolution. We are also interested in obtaining early zygotic promoters that will direct transgene expression in the early embryo as part of a Medea gene drive system. Results Two novel early zygotic kinesin light chain genes we call AaKLC2.1 and AaKLC2.2 were identified by transcriptome sequencing of Aedes aegypti embryos at various time points. These two genes have 98% nucleotide and amino acid identity in their coding regions and show transcription confined to the early zygotic stage according to gene-specific RT-PCR analysis. These AaKLC2 genes have a paralogous gene (AaKLC1 in Ae. aegypti. Phylogenetic inference shows that an ortholog to the AaKLC2 genes is only found in the sequenced genome of Culex quinquefasciatus. In contrast, AaKLC1 gene orthologs are found in all three sequenced mosquito species including Anopheles gambiae. There is only one KLC gene in D. melanogaster and other sequenced holometabolous insects that appears to be similar to AaKLC1. Unlike AaKLC2, AaKLC1 is expressed in all life stages and tissues tested, which is consistent with the expression pattern of the An. gambiae and D. melanogaster KLC genes. Phylogenetic inference also suggests that AaKLC2 genes and their likely C. quinquefasciatus ortholog are fast-evolving genes relative to the highly conserved AaKLC1-like paralogs. Embryonic injection of a luciferase reporter under the control of a

  10. 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.

  11. Efficacy of a mermithid nematode Romanomermis iyengari (Welch) (Nematoda: Mermithidae) in controlling tree hole-breeding mosquito Aedes albopictus (Skuse) (Diptera: Culicidae) in a rubber plantation area of Kerala, India.

    Science.gov (United States)

    Paily, K P; Chandhiran, K; Vanamail, P; Kumar, N Pradeep; Jambulingam, P

    2013-03-01

    In rubber plantations, tree holes are one of the major types of breeding habitats of Aedes mosquitoes which transmit dengue and chikungunya. A mermithid nematode, Romanomermis iyengari, was evaluated in tree holes for its efficacy in controlling Aedes albopictus. Infection of mosquito larvae by the nematode was determined through microscopic examination on the next day of application, and evaluation of immature density of mosquito was done on the seventh day. After application of the infective stage of the nematode in a host-parasite ratio of 1:3 or 1:4, the infection rates on the different larval instars of mosquito were similar, 85.7-95.8 % in first to third instars and 79.3 % in fourth instar larvae or 100 and 92.9 %, respectively. Parasite burden varied from 1.1 to 2.4, respectively, among first and third instar larvae applied at 1:3. At 1:4, the parasite burden was between 1.6 (fourth instar) and 4 (second instar). The increase in parasite burden due to parasite density was significant in all the larval instars (P < 0.05). High parasite burden is detrimental to parasite recycling as it can cause premature mortality of the host. Hence, the dosage of 1:3 could be considered as suitable for rubber tree hole habitats. In the nematode-applied tree holes, there was a significant level (P < 0.05) of reduction in the immature density of A. albopictus, especially late instars and pupae, confirming the efficacy of R. iyengari in infecting the mosquito and controlling pupal emergence. PMID:23306387

  12. Rhamnolipids: solution against Aedes aegypti?

    Directory of Open Access Journals (Sweden)

    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.

  13. Primera cita de mosquito tigre, Aedes albopictus (Diptera, Culicidae), para Andalucía y primera corroboración de los datos de la aplicación Tigatrapp

    OpenAIRE

    Delacour-Estrella, Sarah; Collantes, Francisco; Ruiz-Arrondo, Ignacio; Alarcón-Elbal, Pedro María; Delgado, Juan Antonio; Eritja, Roger; Bartumeus, Frederic; Oltra, Aitana; Palmer, John R.B.; Lucientes, Javier

    2014-01-01

    A partir de los datos proporcionados por los ciudadanos sobre la posible presencia de mosquito tigre a través de la innovadora aplicación Tigatrapp del proyecto AtrapaelTigre.com, se ratifica la presencia de esta especie invasora en el municipio de Alhaurín de la Torre (Málaga). Este trabajo representa la primera cita del vector potencial Aedes albopictus para la Comunidad Autónoma de Andalucía. Aparte de las molestias que causa como insecto fuertemente antropófilo y agre...

  14. Analysis of lipids by gas-liquid chromatography and complementary methods in four strains of Aedes aegypti mosquitoes.

    Science.gov (United States)

    Miller, S; Novak, R J

    1985-01-01

    Fatty acid composition of total lipids, neutral lipids and phospholipids of strains of Aedes aegypti were determined. The fatty acid composition of the strains differed quantitatively with regard to the relative percentage of commonly occurring fatty acids. Gas-liquid chromatography of fatty acid methyl esters showed 18:1 (oleic or elaidic) to be the predominant fatty acid. The fatty acid was identified as oleic by argentation thin-layer chromatography. A modified colorimetric method was used to determine tissue-free fatty acids. The lipids were predominantly triacylglycerol with lesser amounts of free fatty acids and decreasing amount of sterol ester, sterol, monoacylglycerol, diacylglycerol and hydrocarbons. The data show considerable lipid differences between the Caribbean strains (Les Cayes, Haiti, and San Juan, Puerto Rico) and the Jakarta (Indonesia) strain. The Shimba Hills (Kenya) strain was more similar to Jakarta than to the Caribbean strains. The results obtained with the different strains are discussed in relation to the established oral susceptibility to Dengue 1 and Dengue 2, yellow fever, and genetic analysis by isoenzyme studies. PMID:4017543

  15. Diminished reproductive fitness associated with the deltamethrin resistance in an Indian strain of dengue vector mosquito, Aedes aegypti L.

    Science.gov (United States)

    Kumar, Sarita; Thomas, Anita; Samuel, Thomas; Sahgal, Arunima; Verma, Anita; Pillai, M K K

    2009-08-01

    The susceptible (SS) and resistant (DLR) strains of Aedes aegypti selected with deltamethrin and combination of deltamethrin and PBO (1:5) at the larval/adult stage were studied in the laboratory for their reproductive fitness in terms of fecundity, hatchability and longevity of gonotrophic cycles. The DLR strains exhibited 73-88% reduction in the duration of gonotrophic cycles as compared to their SS counterparts. There was a considerable decrease in egg production and hatchability rates in the selected strains of Ae. aegypti, as compared to that of the SS strain. Data indicate deltamethrin being an effective insecticide against Ae. aegypti and a possible correlation between the deltamethrin resistance and disadvantages during reproduction. The most drastic and significant effect was observed in DLR1b strains exhibiting 36.7% decrease in fecundity and 32.4% reduction in hatchability. Another important observation was diminished reproductive fitness in DLR2 strains. This suggests the usefulness of synergized deltamethrin selections in reducing the frequency of resistant individuals. A significant finding was to observe the reproductive disadvantage in adult-selected strains having negligible resistance to deltamethrin implicating the efficacy of deltamethrin as an adulticide rather than as a larvicide. Various probable reasons for the reduction in the reproductive potential and the possible resistance-management strategies of Ae. aegypti are discussed. PMID:19901902

  16. Synergistic effect of Andrographis echioides and Cadaba trifoliata leaf extracts against larvae of dengue mosquito Aedes aegypti L

    Institute of Scientific and Technical Information of China (English)

    Sankaran Rajkumar; Arulsamy Jebanesan; Rajarathinavelu Nagarajan

    2012-01-01

    Objective: The larvicidal potential of Andrographis echioides and Cadaba trifoliata leaf extract was tested separately against larvae of Aedes aegypti and also tested mixture of these two plant extracts for synergistic effect against the larvae. Methods: Pulverized leaves of A. echioides and C.trifoliata were subjected separately to soxhlet extraction using organic solvent of ethanol. These two plant extracts were examined separately against 4th instar larvae of A.aegypti with gradually increasing concentration i.e. from 50 to 250mg/l using WHO protocol. To observe the synergistic effect, extracts of these two plants were mixed at different concentrations and tested against the larva. The 24h LC50 values of individual plant extract and mixed extracts were determined following probit analysis. Results: A. echioides extract shows more lethal effect than C. trifoliata extract towards larvae of A.aegypti with LC50 values of 108.3 and 123.4 mg/l, respectively, whereas , synergistic larvicidal effect was found to be even more effective than the plant extract tested separately in terms of LC50 being 68.3 mg/l. Conclusions: From the results, it is evident that synergistic effect of A. echioides and C. trifoliata can be considered as a more powerful arsenal for the control of A.aegypti than the usage of these two extract separately.

  17. Insecticidal activity of isobutylamides derived from Piper nigrum against adult of two mosquito species, Culex pipiens pallens and Aedes aegypti.

    Science.gov (United States)

    Park, Il-Kwon

    2012-01-01

    The insecticidal activity of Piper nigrum fruit-derived piperidine alkaloid (piperine) and N-isobutylamide alkaloids (pellitorine, guineensine, pipercide and retrofractamide A) against female adults of Culex pipiens pallens and Aedes aegypti was examined. On the basis of 24-h LD(50) values, the compound most toxic to female C. pipiens pallens was pellitorine (0.4 µg/♀) followed by guineensine (1.9 µg/♀), retrofractamide A (2.4 µg/♀) and pipercide (3.2 µg/♀). LD(50) value of chlorpyrifos was 0.03 µg/♀. Against female A. aegypti, the insecticidal activity was more pronounced in pellitorine (0.17 µg/♀) than in retrofractamide A (1.5 µg/♀), guineensine (1.7 µg/♀), and pipercide (2.0 µg/♀). LD(50) value of chlorpyrifos was 0.0014 µg/♀. PMID:22010905

  18. Effects of atmospheric CO{sub 2}, light availability and tree species on the quality of leaf detritus as a resource for treehole mosquitoes

    Energy Technology Data Exchange (ETDEWEB)

    Strand, M.; Herms, D.A.; Walker, E.D.; Merritt, R.W. [Michigan State Univ., Dept. of Entomology, East Lansing, MI (United States); Ayres, M.P. [Dartmouth College, Dept. of Biological Sciences, Hanover, NH (United States); Kubiske, M.E.; Pregitzer, K.S. [Michigan Technological Univ., School of Forestry and Lake Superior Ecosystems Research Center, Houghton, MI (United States); Kaufman, M.G. [Michigan State Univ., W.K. Kellogg Biological Station, Hickory Corners, MI (United States)

    1999-07-01

    Elevated CO{sub 2} could alter the productivity of heterotrophic aquatic ecosystems through effects on allochthonous litter inputs. The effects of atmospheric CO{sub 2} concentration, light availability to trees and tree species, on leaf detritus quality as a food resource for eastern treehole mosquitoes (Aedes triseriatus) were examined. Larvae were reared in laboratory microcosms (simulated treeholes) with naturally-senesced, abscised foliage from seedlings of red oak (Quercus rubra) and paper birch (Betula papyrifera) grown in ambient and elevated atmospheric CO{sub 2} environments. Elevated CO{sub 2} did not have significant effects on any measure of mosquito performance. In contrast, host species and light availability had dramatic effects on mosquito development time and survival; light availability had additional effects on adult size. Mosquito reproductive potential ({+-} SE) averaged 8.4 {+-} 1.5 females female{sup -1}) generation{sup -1} when litter input was from birch-sun leaves, but was 19.6 {+-} 1.8 when the litter was from birch-shade leaves and 13.0 {+-} 1.8 when from oak-sun leaves. Mosquito development time was nearly halved when the litter input was from oak-sun leaves versus birch-sun leaves, suggesting a potential for even greater demographic effects (e.g. two generations per year instead of one could yield a 20-fold increase in annual growth rate). Trophic transfer rates (mg insect detritivore g litter{sup -1} d{sup -1}) were 3-fold greater on birch-shade leaves than on birch-sun leaves. Changes in insolation and tree species composition can have important consequences for forest ecosystems, because of effects on litter quality that impact microbial saprobes and, ultimately, invertebrate detritivores. (au)

  19. A de novo transcriptome of the Malpighian tubules in non-blood-fed and blood-fed Asian tiger mosquitoes Aedes albopictus: insights into diuresis, detoxification, and blood meal processing

    Science.gov (United States)

    Esquivel, Carlos J.; Cassone, Bryan J.

    2016-01-01

    Background. In adult female mosquitoes, the renal (Malpighian) tubules play an important role in the post-prandial diuresis, which removes excess ions and water from the hemolymph of mosquitoes following a blood meal. After the post-prandial diuresis, the roles that Malpighian tubules play in the processing of blood meals are not well described. Methods. We used a combination of next-generation sequencing (paired-end RNA sequencing) and physiological/biochemical assays in adult female Asian tiger mosquitoes (Aedes albopictus) to generate molecular and functional insights into the Malpighian tubules and how they may contribute to blood meal processing (3–24 h after blood ingestion). Results/Discussion. Using RNA sequencing, we sequenced and assembled the first de novo transcriptome of Malpighian tubules from non-blood-fed (NBF) and blood-fed (BF) mosquitoes. We identified a total of 8,232 non-redundant transcripts. The Malpighian tubules of NBF mosquitoes were characterized by the expression of transcripts associated with active transepithelial fluid secretion/diuresis (e.g., ion transporters, water channels, V-type H+-ATPase subunits), xenobiotic detoxification (e.g., cytochrome P450 monoxygenases, glutathione S-transferases, ATP-binding cassette transporters), and purine metabolism (e.g., xanthine dehydrogenase). We also detected the expression of transcripts encoding sodium calcium exchangers, G protein coupled-receptors, and septate junctional proteins not previously described in mosquito Malpighian tubules. Within 24 h after a blood meal, transcripts associated with active transepithelial fluid secretion/diuresis exhibited a general downregulation, whereas those associated with xenobiotic detoxification and purine catabolism exhibited a general upregulation, suggesting a reinvestment of the Malpighian tubules’ molecular resources from diuresis to detoxification. Physiological and biochemical assays were conducted in mosquitoes and isolated Malpighian

  20. Suppression of a Field Population of Aedes aegypti in Brazil by Sustained Release of Transgenic Male Mosquitoes.

    Directory of Open Access Journals (Sweden)

    Danilo O Carvalho

    Full Text Available The increasing burden of dengue, and the relative failure of traditional vector control programs highlight the need to develop new control methods. SIT using self-limiting genetic technology is one such promising method. A self-limiting strain of Aedes aegypti, OX513A, has already reached the stage of field evaluation. Sustained releases of OX513A Ae. aegypti males led to 80% suppression of a target wild Ae. aegypti population in the Cayman Islands in 2010. Here we describe sustained series of field releases of OX513A Ae. aegypti males in a suburb of Juazeiro, Bahia, Brazil. This study spanned over a year and reduced the local Ae. aegypti population by 95% (95% CI: 92.2%-97.5% based on adult trap data and 81% (95% CI: 74.9-85.2% based on ovitrap indices compared to the adjacent no-release control area. The mating competitiveness of the released males (0.031; 95% CI: 0.025-0.036 was similar to that estimated in the Cayman trials (0.059; 95% CI: 0.011-0.210, indicating that environmental and target-strain differences had little impact on the mating success of the OX513A males. We conclude that sustained release of OX513A males may be an effective and widely useful method for suppression of the key dengue vector Ae. aegypti. The observed level of suppression would likely be sufficient to prevent dengue epidemics in the locality tested and other areas with similar or lower transmission.

  1. Suppression of a Field Population of Aedes aegypti in Brazil by Sustained Release of Transgenic Male Mosquitoes.

    Science.gov (United States)

    Carvalho, Danilo O; McKemey, Andrew R; Garziera, Luiza; Lacroix, Renaud; Donnelly, Christl A; Alphey, Luke; Malavasi, Aldo; Capurro, Margareth L

    2015-01-01

    The increasing burden of dengue, and the relative failure of traditional vector control programs highlight the need to develop new control methods. SIT using self-limiting genetic technology is one such promising method. A self-limiting strain of Aedes aegypti, OX513A, has already reached the stage of field evaluation. Sustained releases of OX513A Ae. aegypti males led to 80% suppression of a target wild Ae. aegypti population in the Cayman Islands in 2010. Here we describe sustained series of field releases of OX513A Ae. aegypti males in a suburb of Juazeiro, Bahia, Brazil. This study spanned over a year and reduced the local Ae. aegypti population by 95% (95% CI: 92.2%-97.5%) based on adult trap data and 81% (95% CI: 74.9-85.2%) based on ovitrap indices compared to the adjacent no-release control area. The mating competitiveness of the released males (0.031; 95% CI: 0.025-0.036) was similar to that estimated in the Cayman trials (0.059; 95% CI: 0.011-0.210), indicating that environmental and target-strain differences had little impact on the mating success of the OX513A males. We conclude that sustained release of OX513A males may be an effective and widely useful method for suppression of the key dengue vector Ae. aegypti. The observed level of suppression would likely be sufficient to prevent dengue epidemics in the locality tested and other areas with similar or lower transmission. PMID:26135160

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

    Directory of Open Access Journals (Sweden)

    Analía Francia

    2011-12-01

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

  3. Repellent effect of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) essential oils against the mosquito Aedes albopictus Skuse (Diptera: Culicidae).

    Science.gov (United States)

    Conti, Barbara; Benelli, Giovanni; Leonardi, Michele; Afifi, Fatma U; Cervelli, Claudio; Profeti, Raffaele; Pistelli, Luisa; Canale, Angelo

    2012-07-01

    Aedes albopictus (Diptera: Culicidae) has been one of the fastest spreading insects over the past 20 years. Its medical importance is due to the aggressive daytime human-biting behavior and the ability to vector many viruses, including dengue, LaCrosse, Eastern Equine encephalitis and West Nile viruses. In this research, the essential oils (EOs) extracted from fresh air dried leaves of Salvia dorisiana, S. longifolia, and S. sclarea (Lamiaceae) were evaluated for their repellent activity against A. albopictus by using the human-bait technique. The EOs chemical composition was also investigated, and EOs were divided in three different profiles on the basis of their chemical composition: EO with large amount of monoterpenes from S. sclarea, EO rich in oxygenated sesquiterpenes from S. dorisiana, and S. longifolia EO characterized by similar percentages of monoterpenes and sesquiterpenes. The efficacy protection from S. dorisiana, S. longifolia, and S. sclarea EOs, at dosages ranging from 0.004 to 0.4 μL cm(-2) of skin, was evaluated during 120 min of observation. Results indicated that S. dorisiana, S. longifolia, and S. sclarea EOs had a significant repellent activity (RD(50) =0.00035, 0.00049, and 0.00101 μL cm(-2), respectively), with differences in repellency rates, as a function of oil, dosage, and observation time. S. dorisiana was the most effective oil: at the two higher dosages, it gave almost complete protection (with a protective efficacy of 90.99% and 95.62%, respectively) for 90 min. The best protection time was achieved with S. dorisiana essential oil. It ranged from 9.2 to 92.4 min. Protection times of S. longifolia and S. sclarea oils ranged from 3.2 to 60 min, and from 3.6 to 64.2 min, respectively. Our findings clearly reveal that these EOs have a good repellent activity against A. albopictus, therefore they can be proposed to improve the efficacy of repellent formulations against the Asian tiger mosquito. PMID:22350673

  4. Use of different coloured ovitraps in the surveillance of Aedes mosquitoes in an arid-urban area of western Rajasthan, India

    Directory of Open Access Journals (Sweden)

    Rina Kumawat

    2014-12-01

    Full Text Available Background & objectives: In the absence of any commercially available dengue vaccine or antiviral therapy, controlling the primary mosquito vector, Aedes aegypti, is currently the only means to prevent dengue outbreaks. Ovitraps are being employed as a sensitive method for detecting the presence of Ae. aegypti. Size, colour, material, paddle and use of oviposition attractant have been reported as important factors influencing the efficacy of ovitraps. Methods: For the study of coloured ovitraps baited with grass infusion, 24 households were randomly selected in a locality and five ovitraps/premises were installed. Weekly ovitrap surveys were conducted during the study for four times. Ovitrap data were analyzed on the basis of its location, day-wise percent positivity, presence of eggs laid and inference of different ovitrap parameters were drawn. Results: Grass infusion, used in the ovitraps has highest attractiveness on Day 6 in comparison to other days. Percent positivity of different coloured ovitraps revealed that red coloured ovitraps have highest positivity (92.7%, followed by black and orange (91.7% each, green (76.3% and transparent (45.8%. The individual colour-wise ovitrap positivity revealed that the highest ovitrap positivity on Day 1 was recorded for black colour (21.8%, which on D2 and D3, in case of red colour (37.5 and 26%. However, on D4, D5 and D6 highest number of positive ovitraps was recorded in orange coloured (12.5, 21.9 and 31.3%, respectively and on D7 highest number of positive ovitraps were recorded in transparent (21.9%, followed by green coloured ovitrap (20.8%. The overall location-wise ovitraps positivity revealed that highest positivity was recorded among the ovitraps installed inside bathrooms (92.0%, followed by bedrooms (85.0%, lobby (66.7% and stores (48.3%. Interpretation & conclusion: The study revealed that for immediate detection of the presence of gravid females in a particular locality during epidemics

  5. Salinity-tolerant larvae of mosquito vectors in the tropical coast of Jaffna, Sri Lanka and the effect of salinity on the toxicity of Bacillus thuringiensis to Aedes aegypti larvae

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    Jude Pavilupillai J

    2012-11-01

    Full Text Available Abstract Background Dengue, chikungunya, malaria, filariasis and Japanese encephalitis are common mosquito-borne diseases endemic to Sri Lanka. Aedes aegypti and Aedes albopictus, the major vectors of dengue, were recently shown to undergo pre-imaginal development in brackish water bodies in the island. A limited survey of selected coastal localities of the Jaffna district in northern Sri Lanka was carried out to identify mosquito species undergoing pre-imaginal development in brackish and saline waters. The effect of salinity on the toxicity of Bacillus thuringiensis israelensis larvicide to Ae. aegypti larvae at salinity levels naturally tolerated by Ae. aegypti was examined. Methods Larvae collected at the selected sites along the Jaffna coast were identified and salinity of habitat water determined in the laboratory. The LC50 and LC90 of B. thuringiensis toxin, the active ingredient of a commercial formulation of the larvicide BACTIVEC®, were determined with Ae. aegypti larvae. Bioassays were also carried out at salinities varying from 0 to18 ppt to determine the toxicity of Bacillus thuringiensis to fresh and brackish water-derived larvae of Ae. aegypti. Results Larvae of four Anopheles, two Aedes, one Culex and one Lutzia species were collected from brackish and saline sites with salinity in the range 2 to 68 ppt. The LC50 and LC90 of B. thuringiensis toxin for the second instar larvae of Ae. aegypti in fresh water were 0.006 ppm and 0.013 ppm respectively, with corresponding values for brackish water populations of 0.008 and 0.012 ppm respectively. One hundred percent survival of second instar fresh water and brackish water-derived Ae. aegypti larvae was recorded at salinity up to 10 and 12 ppt and 100% mortality at 16 and 18 ppt, yielding an LC 50 for salinity of 13.9 ppt and 15.4 ppt at 24 h post-treatment respectively for the two populations. Statistical analysis showed significantly reduced toxicity of B. thuringiensis to fresh and

  6. 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.

  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. Efficacy of essential oil from Cananga odorata (Lamk.) Hook.f. & Thomson (Annonaceae) against three mosquito species Aedes aegypti (L.), Anopheles dirus (Peyton and Harrison), and Culex quinquefasciatus (Say).

    Science.gov (United States)

    Soonwera, Mayura

    2015-12-01

    The essential oil of Cananga odorata flowers was evaluated for oviposition-deterrent, ovicidal, insecticidal, and repellent activities toward three mosquito species: Aedes aegypti, Anopheles dirus, and Culex quinquefasciatus. Oviposition deterrence of the oil was evaluated on gravid females using oviposition deterrence bioassay. The results showed that 10 % Ca. odorata exhibited high percent effective repellency against oviposition at 99.4 % to Ae. aegypti, 97.1 % to An. dirus, and 100 % to Cx. quinquefasciatus. Ca. odorata oil was tested for ovicidal activity. Regression equations revealed that the ovicidal rates were positively correlated with the concentrations of the essential oil. As the concentration of essential oil increased from 1, 5, and up to 10 % concentration, the ovicidal rate increased accordingly. Larvicidal activity of the oils was used on immature stages (third and fourth instar lavae and pupae). The maximum larval mortality was found with 10 % Ca. odorata against immature stages, and there were LC50 values ranged from 10.4 to 10.5 % (for Ae. aegypti), mosquito species at 96 % (for Ae. aegypti), 98.4 % (for An. dirus), and 100 % (for Cx. quinquefasciatus), with EC50 values of 6.2, 4.7, and 5.4 %, respectively. It gave moderate mortality rates after 24 and 48 h of exposure. Ca. odorata oil was assessed for repellency to females by using the modified K&D module. Ten percent Ca. odorata oil gave the strongest value against Ae. aegypti, An. dirus, and Cx. quinquefasciatus, with percentage repellency of 66, 92, and 90 %, respectively. This study demonstrates the potential for the essential oil of Ca. odorata essential oil to be used as a botanical insecticide against three mosquito species. PMID:26337270

  9. Radiation cytogenetics of the yellow-fever mosquito Aedes aegypti and the plant genus Collinsia. Final report, April 1967--September 1977

    International Nuclear Information System (INIS)

    The major objectives of the project on Aedes aegypti, which is one of the most important disease vectors of man, were to study the cytogenetic effects of radiation and certain chemical mutagens, the genetics of radiation-induced chromosomal rearrangements with particular attention to reciprocal translocations, and the possibility of using translocations for genetic control of natural populations. Results reported on work done during the years 1967 and 1977 show these objectives have been mostly accomplished

  10. Distribution and seasonality of vertically transmitted dengue viruses in Aedes mosquitoes in arid and semi-arid areas of Rajasthan, India

    OpenAIRE

    Bennet Angel; Vinod Joshi

    2008-01-01

    Background & objectives: Transovarial transmission of dengue virus is a crucial etiological phenomenon responsible for persistence of virus during inter-epidemic period of the disease. Distribution and seasonality of this phenomenon in disease endemic areas may contribute to explain emergence of dengue and its subsequent prevention. The study on seasonal and area distribution of transovarial transmission of dengue virus in Aedes aegypti, Ae. albopictus and Ae. vittatus has been made in desert...

  11. Radiation cytogentics of the yellow-fever mosquito Aedes aegypti and the plant genus Collinsia. Final report, April 1967--September 1977

    Energy Technology Data Exchange (ETDEWEB)

    Rai, K.S.

    1977-01-01

    The major objectives of the project on Aedes aegypti, which is one of the most important disease vectors of man, were to study the cytogenetic effects of radiation and certain chemical mutagens, the genetics of radiation-induced chromosomal rearrangements with particular attention to reciprocal translocations, and the possibility of using translocations for genetic control of natural populations. Results reported on work done during the years 1967 and 1977 show these objectives have been mostly accomplished.

  12. Dopamine levels in the mosquito Aedes aegypti during adult development, following blood feeding and in response to heat stress

    DEFF Research Database (Denmark)

    Andersen, Janne Pleidrup; Schwartz, Alex; Gramsbergen, Jan Bert;

    2006-01-01

    concentrations of dopamine than females, and that dopamine concentrations decrease with age in both sexes. Dopamine levels increase in females following a blood meal suggesting that dopamine might be involved in ovarian- and/or egg-development. We also found that female mosquitoes have a higher tolerance to a...... short term thermal stress in a water bath than males up to 44 degrees C, however, both sexes die if exposed to short term temperatures between 44 and 45 degrees C. Finally, we did not find any indication that dopamine levels were associated with short time thermal stress response in female mosquitoes....

  13. Dopamine levels in the mosquito Aedes aegypti  during adult development, following blood feeding and in response to heat stress

    DEFF Research Database (Denmark)

    Andersen, Janne Pleidrup; Schwartz, Alex Mark; Gramsbergen, J.B.;

    2006-01-01

    concentrations of dopamine than females, and that dopamine concentrations decrease with age in both sexes. Dopamine levels increase in females following a blood meal suggesting that dopamine might be involved in ovarian- and/or egg-development. We also found that female mosquitoes have a higher tolerance to a...... short term thermal stress in a water bath than males up to 44 °C, however, both sexes die if exposed to short term temperatures between 44 and 45 °C. Finally, we did not find any indication that dopamine levels were associated with short time thermal stress response in female mosquitoes. Keywords: HPLC...

  14. Binding of a fluorescence reporter and a ligand to an odorant-binding protein of the yellow fever mosquito, Aedes aegypti

    Science.gov (United States)

    Leal, Gabriel M.; Leal, Walter S.

    2015-01-01

    Odorant-binding proteins (OBPs), also named pheromone-binding proteins when the odorant is a pheromone, are essential for insect olfaction. They solubilize odorants that reach the port of entry of the olfactory system, the pore tubules in antennae and other olfactory appendages. Then, OBPs transport these hydrophobic compounds through an aqueous sensillar lymph to receptors embedded on dendritic membranes of olfactory receptor neurons. Structures of OBPs from mosquito species have shed new light on the mechanism of transport, although there is considerable debate on how they deliver odorant to receptors. An OBP from the southern house mosquito, Culex quinquefasciatus, binds the hydrophobic moiety of a mosquito oviposition pheromone (MOP) on the edge of its binding cavity. Likewise, it has been demonstrated that the orthologous protein from the malaria mosquito binds the insect repellent DEET on a similar edge of its binding pocket. A high school research project was aimed at testing whether the orthologous protein from the yellow fever mosquito, AaegOBP1, binds DEET and other insect repellents, and MOP was used as a positive control. Binding assays using the fluorescence reporter N-phenyl-1-naphtylamine (NPN) were inconclusive. However, titration of NPN fluorescence emission in AaegOBP1 solution with MOP led to unexpected and intriguing results. Quenching was observed in the initial phase of titration, but addition of higher doses of MOP led to a stepwise increase in fluorescence emission coupled with a blue shift, which can be explained at least in part by formation of MOP micelles to house stray NPN molecules. PMID:25671088

  15. Identification of Essential Containers for Aedes Larval Breeding to Control Dengue in Dhaka, Bangladesh

    OpenAIRE

    Ferdousi, Farhana; Yoshimatsu, Shoji; Ma, Enbo; Sohel, Nazmul; Wagatsuma, Yukiko

    2015-01-01

    Dengue fever (DF), one of the most important emerging arboviral diseases, is transmitted through the bite of container breeding mosquitoes Aedes aegypti and Aedes albopictus. A household entomological survey was conducted in Dhaka from August through October 2000 to inspect water-holding containers in indoor, outdoor, and rooftop locations for Aedes larvae. The objective of this study was to determine mosquito productivity of each container type and to identify some risk factors of households...

  16. 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

  17. 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...

  18. 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...

  19. 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...

  20. Creams Formulated with Ocimum gratissimum L. and Lantana camara L. Crude Extracts and Fractions as Mosquito Repellents Against Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Keziah, Ezeike Amarachi; Nukenine, Elias Nchiwan; Danga, Simon Pierre Yinyang; Younoussa, Lame; Esimone, Charles Okechukwu

    2015-01-01

    Mosquitoes are the most deadly vectors of parasites that cause diseases such as malaria, yellow fever, and filariasis. In view of the recent increased interest in developing plant origin insecticides as an alternative to chemical insecticides, the objective of this study was to determine the repellent activity of creams formulated with methanol crude extract (MCE), hexane fraction (HF), and ethyl acetate fractions (EAFs) of Ocimum gratissimum and Lantana camara leaves in single and combined a...

  1. Evaluation of fifteen local plants as larvicidal agents against an Indian strain of dengue fever mosquito, Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Sarita eKumar; Naim eWahab; Monika eMishra; Radhika eWarikoo

    2012-01-01

    The adverse effects of chemical insecticides-based intervention measures for the control of mosquito vectors have received wide public apprehension because of several problems like insecticide resistance, resurgence of pest species, environmental pollution, toxic hazards to humans and non-target organisms. These problems have necessitated the need to explore and development of alternative strategies using eco-friendly, environmentally safe, bio-degradable plant products which are non-toxic to...

  2. Evaluation of 15 Local Plant Species as Larvicidal Agents Against an Indian Strain of Dengue Fever Mosquito, Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Kumar, Sarita; Wahab, Naim; Mishra, Monika; Warikoo, Radhika

    2012-01-01

    The adverse effects of chemical insecticides-based intervention measures for the control of mosquito vectors have received wide public apprehension because of several problems like insecticide resistance, resurgence of pest species, environmental pollution, toxic hazards to humans, and non-target organisms. These problems have necessitated the need to explore and develop alternative strategies using eco-friendly, environmentally safe, bio-degradable plant products which are non-toxic to non-t...

  3. Application of remotely sensed multispectral data to automated analysis of marshland vegetation. Inference to the location of breeding habitats of the salt marsh mosquito (Aedes Sollicitans)

    Science.gov (United States)

    Cibula, W. G.

    1976-01-01

    The techniques used for the automated classification of marshland vegetation and for the color-coded display of remotely acquired data to facilitate the control of mosquito breeding are presented. A multispectral scanner system and its mode of operation are described, and the computer processing techniques are discussed. The procedures for the selection of calibration sites are explained. Three methods for displaying color-coded classification data are presented.

  4. Binding of a fluorescence reporter and a ligand to an odorant-binding protein of the yellow fever mosquito, Aedes aegypti

    OpenAIRE

    Leal, Gabriel M.; Leal, Walter S.

    2015-01-01

    Odorant-binding proteins (OBPs), also named pheromone-binding proteins when the odorant is a pheromone, are essential for insect olfaction. They solubilize odorants that reach the port of entry of the olfactory system, the pore tubules in antennae and other olfactory appendages. Then, OBPs transport these hydrophobic compounds through an aqueous sensillar lymph to receptors embedded on dendritic membranes of olfactory receptor neurons. Structures of OBPs from mosquito species have shed new li...

  5. 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

  6. Comparison of the functional features of the pump organs of Anopheles sinensis and Aedes togoi

    OpenAIRE

    Young-Ran Ha; Seung-Chul Lee; Seung-Jun Seo; Jeongeun Ryu; Dong-Kyu Lee; Sang-Joon Lee

    2015-01-01

    Mosquitoes act as vectors for severe tropical diseases. Mosquito-borne diseases are affected by various factors such as environmental conditions, host body susceptibility, and mosquito feeding behavior. Among these factors, feeding behavior is affected by the feeding pump system located inside the mosquito head and also depends on the species of mosquito. Therefore, the 3D morphological structures of the feeding pumps of Aedes togoi and Anopheles sinensis were comparatively investigated using...

  7. Interspecific Larval Competition Between Aedes albopictus and Aedes japonicus (Diptera: Culicidae) in Northern Virginia

    OpenAIRE

    Armistead, J. S.; Arias, J. R.; Nishimura, N; Lounibos, L. P.

    2008-01-01

    Aedes albopictus (Skuse) and Aedes japonicus (Theobald) are two of the most recent and widespread invasive mosquito species to have become established in the United States. The two species co-occur in water-filled artificial containers, where crowding and limiting resources are likely to promote inter- or intraspecific larval competition. The performance of northern Virginia populations of Ae. japonicus and Ae. albopictus competing as larvae under field conditions was evaluated. Per capita ra...

  8. Antimicrobial activity of mosquito cecropin peptides against Francisella.

    Science.gov (United States)

    Kaushal, Akanksha; Gupta, Kajal; Shah, Ruhee; van Hoek, Monique L

    2016-10-01

    Francisella tularensis is the cause of the zoonotic disease tularemia. In Sweden and Scandinavia, epidemiological studies have implicated mosquitoes as a vector. Prior research has demonstrated the presence of Francisella DNA in infected mosquitoes but has not shown definitive transmission of tularemia from a mosquito to a mammalian host. We hypothesized that antimicrobial peptides, an important component of the innate immune system of higher organisms, may play a role in mosquito host-defense to Francisella. We established that Francisella sp. are susceptible to two cecropin antimicrobial peptides derived from the mosquito Aedes albopictus as well as Culex pipiens. We also demonstrated induced expression of Aedes albopictus antimicrobial peptide genes by Francisella infection C6/36 mosquito cell line. We demonstrate that mosquito antimicrobial peptides act against Francisella by disrupting the cellular membrane of the bacteria. Thus, it is possible that antimicrobial peptides may play a role in the inability of mosquitoes to establish an effective natural transmission of tularemia. PMID:27235883

  9. Mapping urban and peri-urban breeding habitats of Aedes mosquitoes using a fuzzy analytical hierarchical process based on climatic and physical parameters.

    Science.gov (United States)

    Sarfraz, Muhammad Shahzad; Tripathi, Nagesh K; Faruque, Fazlay S; Bajwa, Usama Ijaz; Kitamoto, Asanobu; Souris, Marc

    2014-01-01

    The spread of dengue fever depends mainly on the availability of favourable breeding sites for its mosquito vectors around human dwellings. To investigate if the various factors influencing breeding habitats can be mapped from space, dengue indices, such as the container index, the house index and the Breteau index, were calculated from Ministry of Public health data collected three times annually in Phitsanulok, Thailand between 2009 and 2011. The most influential factors were found to be temperature, humidity, rainfall, population density, elevation and land cover. Models were worked out using parameters mostly derived from freely available satellite images and fuzzy logic software with parameter synchronisation and a predication algorithm based on data mining and the Decision Tree method. The models developed were found to be sufficiently flexible to accommodate additional parameters and sampling data that might improve prediction of favourable breeding hotspots. The algorithm applied can not only be used for the prediction of near real-time scenarios with respect to dengue, but can also be applied for monitoring other diseases influenced by environmental and climatic factors. The multi-criteria model presented is a cost-effective way of identifying outbreak hotspots and early warning systems lend themselves for development based on this strategy. The proposed approach demonstrates the successful utilisation of remotely sensed images to map mosquito breeding habitats. PMID:25599639

  10. Mapping urban and peri-urban breeding habitats of Aedes mosquitoes using a fuzzy analytical hierarchical process based on climatic and physical parameters

    Directory of Open Access Journals (Sweden)

    Muhammad Shahzad Sarfraz

    2014-12-01

    Full Text Available The spread of dengue fever depends mainly on the availability of favourable breeding sites for its mosquito vectors around human dwellings. To investigate if the various factors influencing breeding habitats can be mapped from space, dengue indices, such as the container index, the house index and the Breteau index, were calculated from Ministry of Public health data collected three times annually in Phitsanulok, Thailand between 2009 and 2011. The most influential factors were found to be temperature, humidity, rainfall, population density, elevation and land cover. Models were worked out using parameters mostly derived from freely available satellite images and fuzzy logic software with parameter synchronisation and a predication algorithm based on data mining and the Decision Tree method. The models developed were found to be sufficiently flexible to accommodate additional parameters and sampling data that might improve prediction of favourable breeding hotspots. The algorithm applied can not only be used for the prediction of near real-time scenarios with respect to dengue, but can also be applied for monitoring other diseases influenced by environmental and climatic factors. The multi-criteria model presented is a cost-effective way of identifying outbreak hotspots and early warning systems lend themselves for development based on this strategy. The proposed approach demonstrates the successful utilisation of remotely sensed images to map mosquito breeding habitats.

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

    OpenAIRE

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2015-01-01

    The three main mosquito genera, Anopheles, Aedes and Culex, transmit respectively malaria, dengue and lymphatic filariasis. Current mosquito control strategies have proved unsuccessful, and there still is a substantial number of morbidity and mortality from these diseases. Genetic control methods have now arisen as promising alternative strategies, based on two approaches: the replacement of a vector population by disease-refractory mosquitoes and the release of mosquitoes carrying a lethal g...

  12. Residual efficacy of bifenthrin treated mosquito nets for Aedes albopictus after washing%洗涤对防虫蚊帐中联苯菊酯残效的影响

    Institute of Scientific and Technical Information of China (English)

    吴华; 黄鸿; 刘桂清; 欧剑峰

    2011-01-01

    目的 实验室评价标准洗涤对防虫蚊帐中联苯菊酯残效的影响.方法 防虫蚊帐按照WHO标准洗涤程序洗涤不同次数后,以强迫接触法进行击倒率及死亡率的生物测试,以气相色谱法检测蚊帐中联苯菊酯的残留量.结果 随着洗涤次数的增加,击倒率及死亡率均呈快速下降趋势,洗涤15、20次时,平均击倒率下降39.4%和70.0%,平均死亡率下降25.0%和69.7%,表明洗涤次数对蚊帐的残效影响很大;蚊帐中联苯菊酯含量逐渐减少,洗脱方程C=137.3746e-0.0696t,半衰期T1/2=9.97次,R2=0.9868.结论 蚊帐经标准洗涤后联苯菊酯的含量<28.15 mg/m2则对蚊虫无效果,要取得明显的防蚊效果,蚊帐中联苯菊酯的最终含量必须>42.99 mg/m2.%Objective To evaluate the residual efficacy of bifenthrin against Aedes albopictus on washed mosquito nets. Methods The knockout and fatality rates of mosquito nets after several WHO standard washing procedures were determined using forced exposure tests. Residues were measured using gas chromatography. Results The knockout and fatality rates decreased sharply as the number of washing increased. At the 15th and 20th wash, the average knockout rate decreased by 39.4% and 70.0% respectively, and the average fatality rate dropped 25.0% and 69.7%, respectively, indicating a significant impact of washing on the effect of agent - treated nets. The residue and degradation of bifenthrin conformed to the first - order kinetics equation: C=137.3746e-0.0696t, T1/2=9.97 times, R2=0.9868. Conclusion After washing, mosquito nets were no longer effective when residual bifenthrin content was lower than 28.15 mg/m2. A final content of more than 42.99 mg/m2 should be ensured to maintain noticeable mosquito control efficacy.

  13. Diversity and distribution of tree hole mosquitoes in Puducherry Union Territory, India

    Institute of Scientific and Technical Information of China (English)

    Periyasamy Senthamarai Selvan; Arulsamy Jebanesan; Chinnusamy Makesh Kumar

    2015-01-01

    Objective:To study diversity and distribution of tree hole mosquitoes at Puducherry Union Territory. Methods:Random collections were carried out in tree holes at collection sites by using suction tube. Mosquitoes are identified by standard entomological procedures. Results: A total of 235 mosquitoes were collected from tree holes, comprising 3 genera and 12 species. They are,Aedes aegypti, Aedes albopictus, Aedes stokesi, Aedes simpsoni, Anopheles subpictus, Anopheles stephensi, Anopheles culiciformis, Anopheles maculatus, Culex quinquefasciatus, Culex pseudovishnui, Culex tritaeniorhynchus, and Culex decens. The results reveal thatAedes species is the dominant species in tree holes. Simpson’s dominance index and Shanon-Wiener diversity index of 0.182 7 and 0.833 6 were respectively recorded for all tree hole mosquitoes. Conclusions:The diversity studies of tree hole mosquitoes in the study area are necessary for the implementation of appropriate control strategies.

  14. Diversity and distribution of tree hole mosquitoes in Puducherry Union Territory, India

    Directory of Open Access Journals (Sweden)

    Periyasamy Senthamarai Selvan

    2015-07-01

    Full Text Available Objective: To study diversity and distribution of tree hole mosquitoes at Puducherry Union Territory. Methods: Random collections were carried out in tree holes at collection sites by using suction tube. Mosquitoes are identified by standard entomological procedures. Results: A total of 235 mosquitoes were collected from tree holes, comprising 3 genera and 12 species. They are, Aedes aegypti, Aedes albopictus, Aedes stokesi, Aedes simpsoni, Anopheles subpictus, Anopheles stephensi, Anopheles culiciformis, Anopheles maculatus, Culex quinquefasciatus, Culex pseudovishnui, Culex tritaeniorhynchus, and Culex decens. The results reveal that Aedes species is the dominant species in tree holes. Simpson’s dominance index and Shanon-Wiener diversity index of 0.182 7 and 0.833 6 were respectively recorded for all tree hole mosquitoes. Conclusions: The diversity studies of tree hole mosquitoes in the study area are necessary for the implementation of appropriate control strategies.

  15. 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)

  16. Larvicidal Potential of the Halogenated Sesquiterpene (+)-Obtusol, Isolated from the Alga Laurencia dendroidea J. Agardh (Ceramiales: Rhodomelaceae), against the Dengue Vector Mosquito Aedes aegypti (Linnaeus) (Diptera: Culicidae)

    Science.gov (United States)

    Salvador-Neto, Orlando; Gomes, Simone Azevedo; Soares, Angélica Ribeiro; Machado, Fernanda Lacerda da Silva; Samuels, Richard Ian; Nunes da Fonseca, Rodrigo; Souza-Menezes, Jackson; Moraes, Jorge Luiz da Cunha; Campos, Eldo; Mury, Flávia Borges; Silva, José Roberto

    2016-01-01

    Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (−)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (−)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (−)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound. PMID:26821032

  17. Glytube: a conical tube and parafilm M-based method as a simplified device to artificially blood-feed the dengue vector mosquito, Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    André Luis Costa-da-Silva

    Full Text Available Aedes aegypti, the main vector of dengue virus, requires a blood meal to produce eggs. Although live animals are still the main blood source for laboratory colonies, many artificial feeders are available. These feeders are also the best method for experimental oral infection of Ae. aegypti with Dengue viruses. However, most of them are expensive or laborious to construct. Based on principle of Rutledge-type feeder, a conventional conical tube, glycerol and Parafilm-M were used to develop a simple in-house feeder device. The blood feeding efficiency of this apparatus was compared to a live blood source, mice, and no significant differences (p = 0.1189 were observed between artificial-fed (51.3% of engorgement and mice-fed groups (40.6%. Thus, an easy to assemble and cost-effective artificial feeder, designated "Glytube" was developed in this report. This simple and efficient feeding device can be built with common laboratory materials for research on Ae. aegypti.

  18. Larvicidal Potential of the Halogenated Sesquiterpene (+)-Obtusol, Isolated from the Alga Laurencia dendroidea J. Agardh (Ceramiales: Rhodomelaceae), against the Dengue Vector Mosquito Aedes aegypti (Linnaeus) (Diptera: Culicidae).

    Science.gov (United States)

    Salvador-Neto, Orlando; Gomes, Simone Azevedo; Soares, Angélica Ribeiro; Machado, Fernanda Lacerda da Silva; Samuels, Richard Ian; Nunes da Fonseca, Rodrigo; Souza-Menezes, Jackson; Moraes, Jorge Luiz da Cunha; Campos, Eldo; Mury, Flávia Borges; Silva, José Roberto

    2016-02-01

    Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (-)-elatol and (+)-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (-)-elatol showed moderate larvicidal activity, whereas (+)-obtusol presented higher toxic activity than (-)-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+)-obtusol revealed damage to the intestinal epithelium. Moreover, (+)-obtusol-treated larvae incubated with 2 µM CM-H₂DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+)-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound. PMID:26821032

  19. Larvicidal Potential of the Halogenated Sesquiterpene (+-Obtusol, Isolated from the Alga Laurencia dendroidea J. Agardh (Ceramiales: Rhodomelaceae, against the Dengue Vector Mosquito Aedes aegypti (Linnaeus (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Orlando Salvador-Neto

    2016-01-01

    Full Text Available Dengue is considered a serious public health problem in many tropical regions of the world including Brazil. At the moment, there is no viable alternative to reduce dengue infections other than controlling the insect vector, Aedes aegypti Linnaeus. In the continuing search for new sources of chemicals targeted at vector control, natural products are a promising alternative to synthetic pesticides. In our work, we investigated the toxicity of a bioactive compound extracted from the red alga Laurencia dendroidea J. Agardh. The initial results demonstrated that crude extracts, at a concentration of 5 ppm, caused pronounced mortality of second instar A. aegypti larvae. Two molecules, identified as (−-elatol and (+-obtusol were subsequently isolated from crude extract and further evaluated. Assays with (−-elatol showed moderate larvicidal activity, whereas (+-obtusol presented higher toxic activity than (−-elatol, with a LC50 value of 3.5 ppm. Histological analysis of the larvae exposed to (+-obtusol revealed damage to the intestinal epithelium. Moreover, (+-obtusol-treated larvae incubated with 2 µM CM-H2DCFDA showed the presence of reactive oxygen species, leading us to suggest that epithelial damage might be related to redox imbalance. These results demonstrate the potential of (+-obtusol as a larvicide for use against A. aegypti and the possible mode of action of this compound.

  20. 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...

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

    Science.gov (United States)

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

  2. Early trypsin activity is part of the signal transduction system that activates transcription of the late trypsin gene in the midgut of the mosquito, Aedes aegypti.

    Science.gov (United States)

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

    1995-02-01

    Trypsin activity during the first hours after feeding is essential to induce late trypsin gene expression. These results are consistent with the idea that free amino acids or other products released during digestion might be the initial signal for transcriptional activation of late trypsin. Besides early trypsin, some other factor(s) have to be translated for induction of late trypsin. This is the first case in which the proteolytic activity of a digestive enzyme is part of the signal transduction system which regulates expression of a second gene. The presence of two trypsins allows the mosquito to assess the quality of the meal and adjust the levels of late trypsin for a particular meal with remarkable flexibility. PMID:7711754

  3. Mosquito larvicidal activity of silver nanoparticles synthesised using actinobacterium, Streptomyces sp. M25 against Anopheles subpictus, Culex quinquefasciatus and Aedes aegypti.

    Science.gov (United States)

    Shanmugasundaram, T; Balagurunathan, R

    2015-12-01

    The present work reports the larvicidal potential of microbially synthesised silver nanoparticles (AgNPs) by using an actinobacterium, Streptomyces sp. M25 isolated from Western Ghats, Tamil Nadu, India. The biomass of Streptomyces sp. was exposed to 1 mM silver nitrate (AgNO3) solution. The synthesis of AgNPs was confirmed by visual inspection followed by instrumental analysis such as UV-vis spectroscopy, fourier transform infrared spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy and transmission electron microscopy (TEM) with selected area electron diffraction. Based on the TEM and XRD analysis, the average size of the AgNPs was determined to be 10-35 nm. The biosynthesised AgNPs exhibited significant larvicidal activity against malarial vector, Anopheles subpictus (LC50 51.34 mg/L and χ (2) value of 8.228), filarial vector, Culex quinquefasciatus (LC50 48.98 mg/L and χ (2) value of 14.307) and dengue vector, Aedes aegypti (LC50 60.23 mg/L and χ (2) value of 4.042), respectively. Similarly, AgNO3 had larvicidal activity against malarial vector, A. subpictus (LC50 42.544 mg/L and χ (2) value of 2.561), filarial vector, C. quinquefasciatus (LC50 44.922 mg/L and χ (2) value of 1.693) and dengue vector, A. aegypti (LC50 39.664 mg/L and χ (2) value of 5.724), respectively. The current study is a rapid, cost effective, eco-friendly and single step approach. The Streptomyces sp. M25 is a newly added source for the synthesis of AgNPs with improved larvicidal activity. PMID:26688633

  4. THAP and ATF-2 regulated sterol carrier protein-2 promoter activities in the larval midgut of the yellow fever mosquito, Aedes aegypti.

    Science.gov (United States)

    Peng, Rong; Fu, Qiang; Hong, Huazhu; Schwaegler, Tyler; Lan, Que

    2012-01-01

    Expression of sterol carrier protein-2 (SCP-2) in Aedes aegypti shows a distinct temporal/spatial pattern throughout the life cycle. In order to identify the transcription factors responsible for the larval temporal/spatial regulation of AeSCP-2 transcription, AeSCP-2 promoter activities were studied in vivo via transient transfection of promoter/reporter gene assays. Regulatory sequences upstream -1.3 kb of the transcription start site of AeSCP-2 were found to be critical for the in vivo temporal/spatial promoter activity. Interestingly, the -1.6 kb promoter sequence efficiently drove the larval midgut-specific siRNA expression, indicating that the -1.6 kb upstream sequence is sufficient for temporal/spatial AeSCP-2 transcriptional activity. Four transcription factors were identified in the midgut nuclear extract from feeding larvae via labeled -1.6/-1.3 kb DNA probe pull-down and proteomic analysis. Co-transfection of the promoter/reporter gene with inducible siRNA expression of each transcription factor was performed to confirm the regulatory function of individual transcription factor on AeSCP-2 transcriptional activities in the larval midgut. The results indicate that two of the identified transcription factors, Thanatos-associated protein (THAP) and activating transcription factor-2 (ATF-2), antagonistically control AeSCP-2 transcriptional activity in the midgut of feeding larvae via the regulatory sequences between -1.6 to -1.3 kb 5' upstream of the transcription start site. In vivo expression knockdown of THAP and ATF-2 resulted in significant changes in developmental progression, which may be partially due to their effects on AeSCP-2 expression. PMID:23056538

  5. THAP and ATF-2 regulated sterol carrier protein-2 promoter activities in the larval midgut of the yellow fever mosquito, Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Rong Peng

    Full Text Available Expression of sterol carrier protein-2 (SCP-2 in Aedes aegypti shows a distinct temporal/spatial pattern throughout the life cycle. In order to identify the transcription factors responsible for the larval temporal/spatial regulation of AeSCP-2 transcription, AeSCP-2 promoter activities were studied in vivo via transient transfection of promoter/reporter gene assays. Regulatory sequences upstream -1.3 kb of the transcription start site of AeSCP-2 were found to be critical for the in vivo temporal/spatial promoter activity. Interestingly, the -1.6 kb promoter sequence efficiently drove the larval midgut-specific siRNA expression, indicating that the -1.6 kb upstream sequence is sufficient for temporal/spatial AeSCP-2 transcriptional activity. Four transcription factors were identified in the midgut nuclear extract from feeding larvae via labeled -1.6/-1.3 kb DNA probe pull-down and proteomic analysis. Co-transfection of the promoter/reporter gene with inducible siRNA expression of each transcription factor was performed to confirm the regulatory function of individual transcription factor on AeSCP-2 transcriptional activities in the larval midgut. The results indicate that two of the identified transcription factors, Thanatos-associated protein (THAP and activating transcription factor-2 (ATF-2, antagonistically control AeSCP-2 transcriptional activity in the midgut of feeding larvae via the regulatory sequences between -1.6 to -1.3 kb 5' upstream of the transcription start site. In vivo expression knockdown of THAP and ATF-2 resulted in significant changes in developmental progression, which may be partially due to their effects on AeSCP-2 expression.

  6. Infectivity and pathogenicity of a novel baculovirus, CuniNPV from Culex nigripalpus (Diptera: Culicidae) for thirteen species and four genera of mosquitoes.

    Science.gov (United States)

    Andreadis, Theodore G; Becnel, James J; White, Susan E

    2003-07-01

    The infectivity and pathogenicity of newly discovered baculovirus, CuniNPV (family Baculoviridae, genus Nucleopolyhedrovirus) originally isolated from the mosquito Culex nigripalpus Theobald, was evaluated in laboratory bioassys against thirteen species and four genera of mosquitoes native to the northeastern U.S. Purified virus at a dosage rate of 1.6 x 10(7) occlusion bodies/ml with 10 mM Mg2+ added was used in exposures with second through fourth instars at temperatures ranging from 17 to 27 degrees C. High infection rates and accompanying mortality were achieved in Cx. pipiens L. (83.0-14.4%), Cx. pipiens f. molestus (80.4% infection), and Cx. salinarius Coquillett (48.0-43.1%). Cx. restuans Theobald was also susceptible but infection rates were lower (21.3-12.5%). The gross pathology associated with infection was identical to that reported in Cx. nigripalpus. Infected larvae were lethargic and were often suspended at the water surface. Development of CuniNPV was observed in the nuclei of the midgut epitheial cells in the gastric caeca and posterior region of the stomach of host larvae. One hundred percent mortality was observed in all larvae that exhibited gross symptoms of infection within 4-d p.i. Cx. territans Walker (subgenus Neoculex Dyar) was the only Culex mosquito that was not susceptible. No infections were obtained with any species of Aedes [Ae. vexans (Meigen)], Culiseta [Culiseta morsitans (Theobald)] or Ochlerotatus [Ochlerotatus canadensis (Theobald), Oc. cantator (Coquillett), Oc. communis (De Geer), Oc. excrucians (Walker), Oc. japonicus (Theobald), Ochlerotatus stimulans (Walker), and Ochlerotatus triseriatus (Coquillett)]. The host range of CuniNPV appears to be restricted to Culex mosquitoes within the subgenus Culex. An inhibitory effect on transmission of CuniNPV was observed when a liver powder/Brewer's yeast mixture was used as a source of food reinforcing the critical role of Mg2+ and sensitivity of the infection process to the presence

  7. Evaluation of botanicals as repellents against mosquitoes

    Directory of Open Access Journals (Sweden)

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

    2003-03-01

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

  8. Molecular Perspectives on the Genetics of Mosquitoes

    International Nuclear Information System (INIS)

    Mosquitoes have been a focus of scientific study since the turn of the century, when they were first linked with human diseases. This review concentrates on the three most intensely studied genera, Anopheles, Culex, and Aedes. These genera include the principal vectors of three major groups of human pathogens: malaria parasites of the genus Plasmodium, filarial worms of the genera Wuchereria and Brugia, and numerous arboviruses. Anophelines are the only mosquitoes known to transmit human malaria parasites, a group of organisms that may be responsible for more morbidity and mortality worldwide than any other human pathogen. Anophelines also transmit filarial worms, as do Culex and Aedes species. Among the 14 or more different mosquito genera known to harbor arboviruses (Mattingly, 1973), the most important are Culex and Aedes, which include the principal vectors of yellow fever, dengue, and most encephalitis-causing arboviruses.

  9. Evaluation of botanicals as repellents against mosquitoes

    OpenAIRE

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

    2003-01-01

    Repellent properties of three plant extracts—essential oil (steam distillate) of Zanthoxylumlimonella (fruits), Citrus aurantifolia (leaf) and petroleum ether extract of Z. limonella (fruits)were evaluated as repellent against Aedes (S.) albopictus mosquitoes in mustard (Dhara) and coconut(Parachute) oil base under laboratory conditions. Three concentrations—10, 20 and 30% of therepellents were evaluated. Repellents in mustard oil afforded longer protection time against thebites of Aedes (S.)...

  10. Risk Factors for the Presence of Chikungunya and Dengue Vectors (Aedes aegypti and Aedes albopictus), Their Altitudinal Distribution and Climatic Determinants of Their Abundance in Central Nepal

    OpenAIRE

    Dhimal, Meghnath; Gautam, Ishan; Joshi, Hari Datt; O’Hara, Robert B.; Ahrens, Bodo; Kuch, Ulrich

    2015-01-01

    Background The presence of the recently introduced primary dengue virus vector mosquito Aedes aegypti in Nepal, in association with the likely indigenous secondary vector Aedes albopictus, raises public health concerns. Chikungunya fever cases have also been reported in Nepal, and the virus causing this disease is also transmitted by these mosquito species. Here we report the results of a study on the risk factors for the presence of chikungunya and dengue virus vectors, their elevational cei...

  11. Risk factors for the presence of chikungunya and dengue vectors (Aedes aegypti and Aedes albopictus), their altitudinal distribution and climatic determinants of their abundance in central Nepal

    OpenAIRE

    Dhimal, Meghnath; Gautam, Ishan; Joshi, Hari Datt; O'Hara, Robert B.; Ahrens, Bodo; Kuch, Ulrich

    2015-01-01

    Background: The presence of the recently introduced primary dengue virus vector mosquito Aedes aegypti in Nepal, in association with the likely indigenous secondary vector Aedes albopictus, raises public health concerns. Chikungunya fever cases have also been reported in Nepal, and the virus causing this disease is also transmitted by these mosquito species. Here we report the results of a study on the risk factors for the presence of chikungunya and dengue virus vectors, their elevational ce...

  12. Influence of competing and predatory invertebrate taxa on larval populations of mosquitoes in temporary ponds of wetland areas in Germany

    NARCIS (Netherlands)

    Elono, Alvine Larissa Meyabeme; Liess, Matthias; Duquesne, Sabine

    2010-01-01

    Abundances of mosquito larvae and associated invertebrate communities were assessed in 27 temporary ponds during the spring season in wetland areas of Germany. Four genera of mosquitoes were identified: Aedes, Anopheles, Culex, and Culiseta. We focused our analyses on Aedes spp. because this genus w

  13. Botanicals as Mosquito Larvicides

    Directory of Open Access Journals (Sweden)

    D.R. Nath,

    2006-10-01

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

  14. Resting and Energy Reserves of Aedes albopictus Collected in Common Landscaping Vegetation in St. Augustine, Florida

    OpenAIRE

    Samson, Dayana M.; Qualls, Whitney A.; Roque, Deborah; Naranjo, Diana P.; Alimi, Temitope; Arheart, Kristopher L.; Müller, Günter C; Beier, John C.; Xue, Rui-De

    2013-01-01

    The resting behavior of Aedes albopictus was evaluated by aspirating diurnal resting mosquitoes from common landscape vegetation in residential communities in St. Augustine, FL. Energy reserves of the resting mosquitoes were analyzed to determine if there was a correlation between mosquito resting habitat and energy accumulation. Six species of plants were selected and 9 collections of resting mosquitoes were aspirated from each plant using a modified John W. Hock backpack aspirator during Ju...

  15. A polymerase chain reaction assay to determine infection of Aedes polynesiensis by Wuchereria bancrofti

    OpenAIRE

    Nicolas, L.; Luquiaud, P.; Lardeux, Frédéric; Mercer, D.R.

    1996-01-01

    The sensitivity of a previously described polymerase chain reaction (PCR) assay was improved to detect a single mosquito, infected by as few as 1-2 microfilariae of #Wuchereria bancrofti$, among 20-50 uninfected mosquitoes. Wild-caught #Aedes polynesiensis$ were used to compare assessment of infection by dissection of individuals with the PCR assay of pools of mosquitoes. The PCR assay was at least as sensitive as dissection for detection of mosquitoes infected with #W. bancrofti$. (Résumé d'...

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

    Directory of Open Access Journals (Sweden)

    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.

  17. Field evaluation of three botanical repellents against Psorophora ferox, Aedes atlanticus, and Aedes mitchellae.

    Science.gov (United States)

    Qualls, Whitney A; Xue, Rui-De

    2009-09-01

    Three botanical natural repellents, Swamp Buddy Bug Chaser (AI 12% plant-based essential oils), All Sport (AI plant-based essential oils, benzophenone-3, octinoxate, and octisalate), and Geraniol (AI 25% geraniol oil and lemongrass extract) were evaluated at a field site in Elkton, Florida, to determine the protection time provided against Psorophora ferox, Aedes atlanticus, and Ae. mitchellae. These three products provided different protection times against biting mosquitoes. Geraniol provided the longest protection time from mosquito bites (4 h), followed by All Sport (1.5 h) and Swamp Buddy Bug Chaser (1 h). This study provides the first information about botanical insect repellents against these floodwater mosquito species. PMID:19852232

  18. [Occurrence of Aedes albopictus in the state of Pará, Brazil].

    Science.gov (United States)

    Segura, Maria de Nazaré de Oliveira; Monteiro, Hamilton Antonio de Oliveira; Lopes, Ernani da Silva; da Silva, Orlando Vaz; Castro, Francisco Corrêa; Vasconcelos, Pedro Fernando da Costa

    2003-06-01

    It is first reported the detection of Aedes (Stg) albopictus mosquitoes in state of Par , Brazil, in the urban area of Medicil ndia, a municipality far 90 km from Altamira, where 42 adult mosquitoes were baited using human attraction. All mosquitoes were pooled and inoculated into C6/36 and suckling mice in attempts for virus isolation. No virus was isolated. The occurrence of Aedes albopictus in urban areas of the Amazon region is of concern since dengue and yellow fever viruses are endemic in the Amazon and thus there is a potential risk for this mosquito species to become infected with both viruses. PMID:12792693

  19. Genetically Modified Mosquito: Myth and Reality

    OpenAIRE

    Teh Su Yean; Koh Hock Lye; Yeap Kiew Lee

    2013-01-01

    Sterile Insect Technique (SIT) has been applied successfully in some agricultural pest control programs in the past, but in many cases, success has not been sustainable in the long run. Various attempts have been made to duplicate this limited success SIT application in agriculture to other areas of applications, particularly in vector control. For example, a recent mosquito control program has been initiated in Malaysia to eliminate dengue-mosquitoes Aedes aegypti by releasing large amount o...

  20. 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...

  1. Pengaruh Ekstrak Daun Kenikir (Tagetes erecta L.) Sebagai Repellent Terhadap Nyamuk Aedes spp.

    OpenAIRE

    Hutagalung, Dwisyahputra

    2013-01-01

    Recently, in Indonesia Dengue Hemorrhagic Fever (DHF) is still public health problems. The morbidity rate for this desease tends to raise for the period of 2005-2009. This desease is an contagious desease caused by the dengue virus and transmitted through the Aedes aegypti Aedes albopictus mosquitoes. The aim of this research was to analyze the effect of extract marigolds (Tagetes erecta L.) leaves as the repellent to the Aedes spp. The design of this research was the quasi-experimental...

  2. 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...

  3. NO BUG: biobased mosquitoes repellent personal protective equipment (PPE)

    OpenAIRE

    Ciera, Lucy Wanjiru; Nierstrasz, Vincent; Van Langenhove, Lieva

    2012-01-01

    In tropical regions (South America, Asia and Africa) diseases like malaria and dengue cause many deaths. These diseases are transmitted through mosquitoes bites (Anopheles sp. and Aedes aegypti respectively). The current practice to protect against transmission of these diseases is by use of mosquito repellents. Common mosquito repellents used today are synthetic in nature and are suspected or have been proved to be harmful to the user and environment (e.g. DEET, DDT, dimethylphylphthalate, p...

  4. Cues of mosquito host finding and oviposition site selection

    OpenAIRE

    Afify, Ali

    2014-01-01

    The aim of this work was to study odor cues that affect mosquito host seeking and oviposition behavior. Due to the vastness (and sometimes contradictions) of mosquito oviposition cues available in literature, I started by reviewing these cues, their source in nature, and their role in mosquito oviposition. Then, I tested the oviposition response of Aedes aegypti towards the contradictory oviposition odor p-cresol and its isomer m-cresol in different situations.p-cresol showed an oviposition d...

  5. Mosquitoes rely on their gut microbiota for development

    OpenAIRE

    Coon, Kerri L.; Vogel, Kevin J.; Brown, Mark R.; Strand, Michael R

    2014-01-01

    Field studies indicate adult mosquitoes (Culicidae) host low diversity communities of bacteria that vary greatly among individuals and species. In contrast, it remains unclear how adult mosquitoes acquire their microbiome, what influences community structure, and whether the microbiome is important for survival. Here we used pyrosequencing of 16S rRNA to characterize the bacterial communities of three mosquito species reared under identical conditions. Two of these species, Aedes aegypti and ...

  6. Algae and blue-green algae as mosquito food

    OpenAIRE

    Rettich, František; Popovský, Jiří; Cepák, Vladimír

    2001-01-01

    Ten genera of cyanophytes and 73 genera of algae were found in the guts of Aedes, Culex, Anopheles and Culiseta larvae collected in various breeding places of the Elbe-Lowland (Bohemia) and Prague. The quality and quantity of blue-green algae and algae found in mosquito guts depended on their presence in the water of mosquito breeding places and on the feeding type (filter fieders, scrapers) of mosquito larvae. Chlorophycean algae possesing cell wall with sporopollenin and algae with a mucila...

  7. Infestation status Aedes albopictus and related mosquito-borne infectious disease risk in central urban area in Shanghai%上海中心城区白纹伊蚊侵害状况及蚊媒传染病危险性分析

    Institute of Scientific and Technical Information of China (English)

    高强; 熊成龙; 周毅彬; 曹晖; 姜庆五

    2016-01-01

    目的 了解白纹伊蚊在上海中心城区的侵害状况,分析蚊媒传染病在上海城市环境的流行与传播风险.方法 采用CO2法在上海城区绿地与居民区环境进行连续性成蚊观察,分析白纹伊蚊种群密度及季节消长趋势特点及新变化;对城区采集的白纹伊蚊样本进行核酸提取并测序,通过与疫区伊蚊进行序列比对,分析上海城区白纹伊蚊对相关蚊媒病毒的易感性及流行风险.结果 白纹伊蚊是上海中心城区的优势蚊种,住区白纹伊蚊构成比(78.53%)高于绿地(19.99%),差异有统计学意义(x2=15 525.168,P<0.001).白纹伊蚊在住区环境的密度[分别为11.91、42.02只/(天·观察点)]均高于绿地环境[分别为3.65、2.18、2.73只/(天·观察点)],差异有统计学意义(F=7.704,均P<0.001);2014年住区环境白纹伊蚊呈明显上升的趋势[构成比94.69%,平均密度42.02只/(天·观察点)],其中旧式里弄环境白纹伊蚊密度最高.上海市的白纹伊蚊与2005-2011年非洲开展白纹伊蚊基因分型在进化树上的遗传距离甚大.结论 上海及相邻地区不存在埃及伊蚊,但市中心白纹伊蚊侵害明显,大幅降低白纹伊蚊的侵害是控制寨卡病毒传播的关键.%Objective To evaluate Aedes albopictus infestation status in the central urban area of Shanghai,and analyze the related epidemic risk of mosquito-borne infectious disease.Methods Consecutive mosquito surveillance was conducted in the green lands and residential areas in the central urban area of Shanghai during 2012-2014,the Aedes albopictas density and its seasonal fluctuation were observed;the sequence ofAedes albopictus in Shanghai was aligned with that in other epidemic area abroad,and the susceptibility ofAedes albopictus to mosquito-borne virus and endemic risk were analyzed.Results No Aedes aegypti was found in the central urban area of Shanghai.As predominant species in both the residential area and the green lands

  8. Geographic distribution of wolbachial infections in mosquitoes from Thailand.

    Science.gov (United States)

    Wiwatanaratanabutr, Itsanun

    2013-11-01

    Members of the genus Wolbachia are inherited intracellular bacterial endosymbionts that infect a diverse range of arthropods. Here I report the results of a survey of these endosymbionts in different mosquito species from six geographic regions of Northern, Northeastern, Western, Central, Eastern and Southern Thailand. Using gene amplification assays with wsp and groE gene primers, wolbachiae were detected in 999 mosquitoes representing 28 species of 1622 specimens collected representing 74 species of wild-caught mosquitoes from all regions of Thailand. Results using wsp primers were similar to those using groE primers in all cases. Wolbachiae had not been reported previously from five of the species tested, namely, Aedes lineatopennis, Aedes vexans, Aedes vittatus, Culex pallidothorax and Culex whitmorei. Infections were found in all major disease vector genera except Anopheles. These results indicate that wolbachial infections are distributed throughout many mosquito species in Thailand. PMID:23660513

  9. 云南省蚊媒传播性疾病的控制问题%VECTOR OF MOSQUITO BORNE DISEASE CONTROL PROBLEMS IN YUNNAN PROVINCE OF CHINA

    Institute of Scientific and Technical Information of China (English)

    周红宁; 董学书; Chris Curtis

    2005-01-01

    @@ Mosquito-borne diseases in Yunnan, mainly consist of malaria (Plasmodium vivax and Plasmodium falcipurium) [1,2] and Japanese encephalitis (JE).No clinic dengue fever and filariasis patients were reported in Yunnan.But in neighboring region Guangxi, these two diseases occur [3,4].In Yunnan, some Aedes mosquitoes such as Aedes albopitus have been detected carrying dengue virus[5].

  10. 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.

  11. Preferências alimentares e domiciliação de mosquitos Culicidae no Vale do Ribeira, São Paulo, Brasil, com especial referência a Aedes scapularis e a Culex (Melanoconion Feeding preferences and domiciliation of Culicidae mosquitoes in the Ribeira Valley, S. Paulo State, Brazil, with particular reference to Aedes scapularis and Culex (Melanoconion

    Directory of Open Access Journals (Sweden)

    Oswaldo Paulo Forattini

    1989-02-01

    Full Text Available Apresentam-se novos dados sobre a identificação do sangue ingerido por culicídeos ingurgitados e coletados em quatro localidades do Vale do Ribeira, Estado de São Paulo (Brasil, no período de fevereiro a novembro de 1986, e que já tinham sido sede de observações anteriores. São fornecidos dados sobre a distribuição de algumas espécies relacionadas ao tipo de ambiente. Focalizam-se Ae. scapularis e representantes de Culex (Melanoconion, principalmente Cx. ribeirensis e Cx. sacchettae. Foi possível a identificação de 651 repastos sangüíneos. Confirmou-se a preferência de Ae. scapularis por mamíferos de grande porte representados por bovinos, eqüinos e o próprio homem, tendo reagido a todos os anti-soros testados, com exceção do correspondente a animais de sangue frio representados por anfíbio. Cx. ribeirensis revelou resultados que sugerem possível preferência por mamíferos. As duas espécies supracitadas mostram tendência nítida para adaptação ao ambiente modificado pelo homem e capacidade de evolução de seus hábitos de possível domiciliação. Quanto aos outros culicídeos, as coletas de An. bellator, An. cruzii e Cq. chrysonotum limitaram-se à isca humana que a segunda dessas espécies rendeu 31,6% do total de fêmeas capturadas.New results on blood-meal identification and the environmental distribution of mosquitoes collected in four different Ribeira Valley (S. Paulo State, Brazil environments, during the period February to November 1986, are presented. Sources of 651 blood-meals were identified. The preference of Ae. scapularis for large mammals, chiefly cattle, horse and even man, was confirmed. Data suggests that a similar behavioral pattern is presented by Cx. ribeirensis. Both mosquitoes seem to be strongly attracted by peridomiciliar blood sources represented by domestic animals sheltered in that environment. Nevertheless, the female of Ae. scapularis females may use the extradomiciliary environment

  12. Alternativas biológicas para el control de los mosquitos Aedes aegypti y Culex pipiens : Transmisores de enfermedades en la ciudad de La Plata

    OpenAIRE

    Tranchida, María Cecilia

    2010-01-01

    Los mosquitos son insectos conocidos por las molestias que causan sus picaduras y porque mediante ellas transmiten importantes enfermedades a los humanos y a otros mamíferos. Esta capacidad de transmitir enfermedades, es conocida como capacidad vectorial. Debido a esta capacidad de actuar como vectores, es que nace la necesidad de controlar a los mosquitos, manteniendo las poblaciones en bajas densidades.

  13. An Odorant Receptor from the Southern House Mosquito Culex pipiens quinquefasciatus Sensitive to Oviposition Attractants

    OpenAIRE

    Pelletier, Julien; Hughes, David T.; Luetje, Charles W.; Leal, Walter S.

    2010-01-01

    Background Insect odorant receptors (ORs) are heteromers comprised of highly variable odorant-binding subunits associated with one conserved co-receptor. They are potential molecular targets for the development of novel mosquito attractants and repellents. ORs have been identified in the malaria mosquito, Anopheles gambiae, and in the yellow fever mosquito, Aedes aegypti. However, they are still unknown in the Southern house mosquito, Culex quinquefasciatus, which transmits pathogens that cau...

  14. Evidence of multiple inseminations in the field in Aedes albopictus.

    Directory of Open Access Journals (Sweden)

    Sebastien Boyer

    Full Text Available Studies on the biology and mating behaviour of male mosquitoes are of major importance in a frame of a Sterile Insect Technique which could be used against mosquito vector species. Most particularly, the assumption of possible multiple inseminations in mosquito species must be investigated in order to optimize alternative mosquito control methods (Sterile Insect Techniques with genetically modified mosquitoes, cytoplasmic incompatibility, radiation…. The occurrence of multiple insemination events was investigated after 2 field samplings of Aedes albopictus (Diptera: Culicidae in La Reunion Island using microsatellite markers. Respectively, 14 and 13 females after the first and the second sampling laid eggs. Seven wild females out of the 27 laying females were found with a progeny involving more than one father. This result is important for the new alternative mosquito control methods and raises the importance of pre- and post-copulatory competition.

  15. The maxillary palp of aedes aegypti, a model of multisensory integration

    Science.gov (United States)

    Female yellow-fever mosquitoes, Aedes aegypti, are obligate blood-feeders and vectors of the pathogens that cause dengue fever, yellow fever and Chikungunya. This feeding behavior concludes a series of multisensory events guiding the mosquito to its host from a distance. The antennae and maxillary...

  16. Bionomic response of Aedes aegypti to two future climate change scenarios in far north Queensland, Australia: implications for dengue outbreaks

    OpenAIRE

    Williams, Craig R.; Mincham, Gina; Ritchie, Scott A.; Viennet, Elvina; Harley, David

    2014-01-01

    Background Dengue viruses are transmitted by anthropophilic mosquitoes and infect approximately 50 million humans annually. To investigate impacts of future climate change on dengue virus transmission, we investigated bionomics of the mosquito vector, Aedes aegypti. Methods Using a dynamic life table simulation model (the Container inhabiting mosquito simulation CIMSiM) and statistically downscaled daily values for future climate, we assessed climate change induced changes to mosquito bionomi...

  17. Globally invasive, withdrawing at home: Aedes albopictus and Aedes japonicus facing the rise of Aedes flavopictus

    Science.gov (United States)

    Chaves, Luis Fernando

    2016-04-01

    It has been suggested that climate change may have facilitated the global expansion of invasive disease vectors, since several species have expanded their range as temperatures have warmed. Here, we present results from observations on two major global invasive mosquito vectors (Diptera: Culicidae), Aedes albopictus (Skuse) and Aedes japonicus (Theobald), across the altitudinal range of Mt. Konpira, Nagasaki, Japan, a location within their native range, where Aedes flavopictus Yamada, formerly a rare species, has now become dominant. Spatial abundance patterns of the three species suggest that temperature is an important factor influencing their adult distribution across the altitudinal range of Mt. Konpira. Temporal abundance patterns, by contrast, were associated with rainfall and showed signals of density-dependent regulation in the three species. The spatial and temporal analysis of abundance patterns showed that Ae. flavopictus and Ae. albopictus were negatively associated, even when accounting for differential impacts of weather and other environmental factors in their co-occurrence patterns. Our results highlight a contingency in the expansion of invasive vectors, the potential emergence of changes in their interactions with species in their native communities, and raise the question of whether these changes might be useful to predict the emergence of future invasive vectors.

  18. Vector competence of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) for the DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus in Fujian, China.

    Science.gov (United States)

    Guo, Xiao-Xia; Li, Chun-Xiao; Zhang, Ying-Mei; Xing, Dan; Dong, Yan-De; Zhang, Heng-Duan; Qin, Cheng-Feng; Zhao, Tong-Yan

    2016-09-01

    Dengue is an acute, emerging, infectious disease transmitted by Aedes mosquitoes that has become a serious global public health problem. The DEN2-FJ10 and DEN2-FJ11 strains of the dengue 2 virus were originally isolated from the serum of a patient with dengue fever in Fujian Province, China, in 1999. Our data provide the first assessment of the vector competence of Aedes mosquitoes with respect to the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus. There were significant differences in the replication rates of these two viral strains in Aedes albopictus and Aedes aegypti (P0.05). In summary, our results indicate that Ae. albopictus and Ae. aegypti mosquitoes are moderately competent vectors of the DEN2-FJ10 and DEN2-FJ11 strains of the dengue virus and provide the first evidence of the effect of these two viral strains on the vector competence of mosquitoes in China. PMID:27260668

  19. 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

  20. 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...

  1. Distribution and occurrence of mosquito species in the municipal areas of Imo State, Nigeria

    OpenAIRE

    Ifeyinwa Celestina MGBEMENA; Tochi EBE

    2012-01-01

    A study of the ecology of drainage - breeding mosquito vectors was conducted in the three urban centers (Owerri, Orlu and Okigwe) of Imo State, Nigeria. Four drainage sites located around markets, residential, stream and hotel premises were selected in each urban centre. Dipping method of sampling was employed and a total of 8,820 mosquitoes comprising eight species namely; Aedes aegypti, Aedes vittatus, Culex quinquefasciatus, Culex tigripes, Culex horridus, Culex cinereus, Culex annuliorus ...

  2. 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...

  3. 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...

  4. 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...

  5. 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.

  6. Genetically Modified Mosquito: Myth and Reality

    Directory of Open Access Journals (Sweden)

    Teh Su Yean

    2013-02-01

    Full Text Available Sterile Insect Technique (SIT has been applied successfully in some agricultural pest control programs in the past, but in many cases, success has not been sustainable in the long run. Various attempts have been made to duplicate this limited success SIT application in agriculture to other areas of applications, particularly in vector control. For example, a recent mosquito control program has been initiated in Malaysia to eliminate dengue-mosquitoes Aedes aegypti by releasing large amount of genetically modified GM male mosquitoes into the field to outcompete the wild male mosquitoes. Field experimental data that has been made available in the literature is limited, rendering it difficult to make independent assessment on its short-term efficacy and long-term sustainability of this GM control strategy. This paper presents a preliminary assessment of the effectiveness of GM mosquito in controlling dengue mosquito population by means of model simulations via DEER (Dengue Encephalitis Eradication Routines. Preliminary results indicate negative conclusion regarding the effectiveness of GM mosquitoes in controlling wild A. aegypti population over the long-term. Essentially, significant reduction of wild mosquito population is possible only if large over-flooding ratios are applied. Further, repeated releases must be maintained over an infinite time horizon to continue to sustain low population of mosquitoes. Major difficulty remains to be resolved. In particular, in-depth costbenefit analysis on this control program is essential to ensure long-term institutional and social support.

  7. The monitoring of mosquitoes (Diptera, Culicidae) in the area affected by the Gabcikovo hydroelectric power structures

    International Nuclear Information System (INIS)

    Monitoring of the impact of the Gabcikovo hydroelectric power structures on mosquitoes (Diptera, Culicidae) in 8 areas and 16 stationary stands during 1990-1994 is presented. The following 9 species of mosquitoes were ascertained: Anopheles maculipennis, s.1, Culiseta annulata, Aedes vexans, Aedes sticticus, Aedes dorsalis, Aedes cinereus, Culex pipiens, Culex territans a Culex modestus. Important changes in the quantity as well as the quality of mosquitoes, were observed in connection with the changes in the ground water level. In 1994 we recorded only 4 species of mosquitoes: Anopheles maculipennis s.1, Aedes vexans, Aedes sticticus, Culex territans. The quantity of mosquitoes decreased significantly at all monitored stands near the river Danube upstream of the confluence with the tail race canal. Cunovo reservoir acted positively on the adjacent monitoring localities Kopac Island and Cunovo-Ostrovne lucky. The recorded communities of mosquitoes Anopheles maculipennis s.1 a Culex territans, are, according to our observations, typical for stabilised water levels. (author). 1 tab., 2 refs

  8. Post-hurricane Rita mosquito surveillance and the efficacy of Air Force aerial applications for mosquito control in east Texas.

    Science.gov (United States)

    Breidenbaugh, Mark S; Haagsma, Karl A; Walker, Wes W; Sanders, David M

    2008-06-01

    Post-Hurricane Rita mosquito surveillance was carried out in 4 east Texas counties to determine mosquito abundance, species composition, and need for mosquito control. Subsequently, aerial applications of naled (Dibrom) for mosquito control were made by the Air Force Aerial Spray Flight, while continued surveillance documented the efficacy of the applications. Psorophora columbiae was the predominant species in landing counts. Twenty-two mosquito species were represented in light trap collections with Aedes atlanitcus/tormentor, Culex nigripalpus, Ae. vexans, and Ps. columbiae making up 91% of the total. A total of 102,001 ha (252,052 acres) were aerially treated based on high mosquito abundance, exposure of first responders and residents to nuisance biting, and local interruption of electric utilities. A significant 90% decline in mosquito abundance was observed posttreatment. PMID:18666545

  9. 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.

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

    Directory of Open Access Journals (Sweden)

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

    Science.gov (United States)

    Vazeille, Marie; Yebakima, André; Girod, Romain; Goindin, Daniella; Dupont-Rouzeyrol, Myrielle; Lourenço-de-Oliveira, Ricardo; Failloux, Anna-Bella

    2016-01-01

    Background 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. Methodology/Principal Findings 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. Conclusions/Significance 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. PMID:26938868

  12. Identification of Essential Containers for Aedes Larval Breeding to Control Dengue in Dhaka, Bangladesh.

    Science.gov (United States)

    Ferdousi, Farhana; Yoshimatsu, Shoji; Ma, Enbo; Sohel, Nazmul; Wagatsuma, Yukiko

    2015-12-01

    Dengue fever (DF), one of the most important emerging arboviral diseases, is transmitted through the bite of container breeding mosquitoes Aedes aegypti and Aedes albopictus. A household entomological survey was conducted in Dhaka from August through October 2000 to inspect water-holding containers in indoor, outdoor, and rooftop locations for Aedes larvae. The objective of this study was to determine mosquito productivity of each container type and to identify some risk factors of households infested with Aedes larvae. Of 9,222 households inspected, 1,306 (14.2%) were positive for Aedes larvae. Of 38,777 wet containers examined, 2,272 (5.8%) were infested with Aedes larvae. Containers used to hold water, such as earthen jars, tanks, and drums were the most common containers for larval breeding. Tires in outdoor and rooftop locations of the households were also important for larval breeding. Although present in abundance, buckets were of less importance. Factors such as independent household, presence of a water storage system in the house, and fully/partly shaded outdoors were found to be significantly associated with household infestation of Aedes larvae. Identification and subsequent elimination of the most productive containers in a given area may potentially reduce mosquito density to below a level at which dengue transmission may be halted. PMID:26865829

  13. Integrating the Public in Mosquito Management: Active Education by Community Peers Can Lead to Significant Reduction in Peridomestic Container Mosquito Habitats

    OpenAIRE

    Healy, Kristen; Hamilton, George; Crepeau, Taryn; Healy, Sean; Unlu, Isik; Farajollahi, Ary; Fonseca, Dina M

    2014-01-01

    Mosquito species that utilize peridomestic containers for immature development are commonly aggressive human biters, and because they often reach high abundance, create significant nuisance. One of these species, the Asian tiger mosquito Aedes albopictus, is an important vector of emerging infectious diseases, such as dengue, chikungunya, and Zika fevers. Integrated mosquito management (IMM) of Ae. albopictus is particularly difficult because it requires access to private yards in urban and s...

  14. Mosquito consumption by insectivorous bats: does size matter?

    Science.gov (United States)

    Gonsalves, Leroy; Bicknell, Brian; Law, Brad; Webb, Cameron; Monamy, Vaughan

    2013-01-01

    Insectivorous bats have often been touted as biological control for mosquito populations. However, mosquitoes generally represent only a small proportion of bat diet. Given the small size of mosquitoes, restrictions imposed on prey detectability by low frequency echolocation, and variable field metabolic rates (FMR), mosquitoes may not be available to or profitable for all bats. This study investigated whether consumption of mosquitoes was influenced by bat size, which is negatively correlated with echolocation frequency but positively correlated with bat FMR. To assess this, we investigated diets of five eastern Australian bat species (Vespadelus vulturnus Thomas, V. pumilus Gray, Miniopterus australis Tomes, Nyctophilus gouldi Tomes and Chalinolobus gouldii Gray) ranging in size from 4-14 g in coastal forest, using molecular analysis of fecal DNA. Abundances of potential mosquito and non-mosquito prey were concurrently measured to provide data on relative prey abundance. Aedes vigilax was locally the most abundant mosquito species, while Lepidoptera the most abundant insect order. A diverse range of prey was detected in bat feces, although members of Lepidoptera dominated, reflecting relative abundance at trap sites. Consumption of mosquitoes was restricted to V. vulturnus and V. pumilus, two smaller sized bats (4 and 4.5 g). Although mosquitoes were not commonly detected in feces of V. pumilus, they were present in feces of 55 % of V. vulturnus individuals. To meet nightly FMR requirements, Vespadelus spp. would need to consume ~600-660 mosquitoes on a mosquito-only diet, or ~160-180 similar sized moths on a moth-only diet. Lower relative profitability of mosquitoes may provide an explanation for the low level of mosquito consumption among these bats and the absence of mosquitoes in feces of larger bats. Smaller sized bats, especially V. vulturnus, are likely to be those most sensitive to reductions in mosquito abundance and should be monitored during mosquito

  15. Multiple chemosensory targets for discovery of novel chemicals for disruption of mosquito behavior

    Science.gov (United States)

    The yellow-fever mosquito Aedes aegypti is an important vector of diseases including dengue fever, yellow fever, chikungunya and West Nile virus. Olfactory and gustatory signals play important roles in the orientation of female mosquitoes to vertebrate hosts and initiation of blood feeding. Using re...

  16. Retrogenes Reveal the Direction of Sex-Chromosome Evolution in Mosquitoes

    Science.gov (United States)

    Toups, Melissa A.; Hahn, Matthew W.

    2010-01-01

    The mosquito Anopheles gambiae has heteromorphic sex chromosomes, while the mosquito Aedes aegypti has homomorphic sex chromosomes. We use retrotransposed gene duplicates to show an excess of movement off the An. gambiae X chromosome only after the split with Ae. aegypti, suggesting that their ancestor had homomorphic sex chromosomes. PMID:20660646

  17. 具有不育控制的埃及伊蚊种群模型的全局动态%Global Dynamics of a Mathematical Model for the Control of Aedes aegypti Mosquitoes by the Sterile Insect Release Technique

    Institute of Scientific and Technical Information of China (English)

    聂玉稳; 刘贤宁; 宋杨

    2012-01-01

    给出了一个描述具有不育雄蚊作为生物控制的埃及伊蚊种群动力系统的模型.研究了边界平衡点及正平衡点存在和稳定的条件,得到了当正平衡点不存在时,边界平衡点全局渐近稳定的条件,即投放不育雄蚊使得野生蚊子种群灭亡的充分条件.%In this paper, a mathematical model is presented describing the dynamics of mosquito population with biological control by sterile male mosquito releasing. The existence and stability of the boundary and positive equilibria are investigated. We obtain the conditions for the global asymptotical stability of the boundary equilibrium when the positive equilibria do not exist, that is, the threshold for making wild mosquito population extinct by releasing sterile male mosquitoes.

  18. Binding of a fluorescence reporter and a ligand to an odorant-binding protein of the yellow fever mosquito, Aedes aegypti [v2; ref status: indexed, http://f1000r.es/4yp

    Directory of Open Access Journals (Sweden)

    Gabriel M. Leal

    2015-01-01

    Full Text Available Odorant-binding proteins (OBPs, also named pheromone-binding proteins when the odorant is a pheromone, are essential for insect olfaction. They solubilize odorants that reach the port of entry of the olfactory system, the pore tubules in antennae and other olfactory appendages. Then, OBPs transport these hydrophobic compounds through an aqueous sensillar lymph to receptors embedded on dendritic membranes of olfactory receptor neurons. Structures of OBPs from mosquito species have shed new light on the mechanism of transport, although there is considerable debate on how they deliver odorant to receptors. An OBP from the southern house mosquito, Culex quinquefasciatus, binds the hydrophobic moiety of a mosquito oviposition pheromone (MOP on the edge of its binding cavity. Likewise, it has been demonstrated that the orthologous protein from the malaria mosquito binds the insect repellent DEET on a similar edge of its binding pocket. A high school research project was aimed at testing whether the orthologous protein from the yellow fever mosquito, AaegOBP1, binds DEET and other insect repellents, and MOP was used as a positive control. Binding assays using the fluorescence reporter N-phenyl-1-naphtylamine (NPN were inconclusive. However, titration of NPN fluorescence emission in AaegOBP1 solution with MOP led to unexpected and intriguing results. Quenching was observed in the initial phase of titration, but addition of higher doses of MOP led to a stepwise increase in fluorescence emission coupled with a blue shift, which can be explained at least in part by formation of MOP micelles to house stray NPN molecules.

  19. Pathogenicity Tests on Nine Mosquito Species and Several Non-target Organisms with Strelkovimermis spiculatus (Nemata Mermithidae)

    OpenAIRE

    BECNEL, JAMES J.; Johnson, Margaret A

    1998-01-01

    Nine species of mosquitoes and several species of non-target aquatic organisms were tested for susceptibility to the mernaithid nematode, Strelkovimermis spiculatus. All species of Anopheles, Aedes, Culex, and Toxorhynchites exposed to S. spiculatus were susceptible. Of the nine mosquito species tested, C. pipiens quinquefasciatus had the greatest tolerance to initial invasion and the highest percent infection of those that survived. High levels of infection were also achieved with Aedes taen...

  20. Global stability of a delayed mosquito-transmitted disease model with stage structure

    OpenAIRE

    B. G. Sampath Aruna Pradeep; Wanbiao Ma

    2015-01-01

    This article presents a new eco-epidemiological deterministic delay differential equation model considering a biological controlling approach on mosquitoes, for endemic dengue disease with variable host (human) and variable vector (Aedes aegypti) populations, and stage structure for mosquitoes. In this model, predator-prey interaction is considered by using larvae as prey and mosquito-fish as predator. We give a complete classification of equilibria of the model, ...

  1. Germline transformation of Aedes fluviatilis (Diptera:Culicidae) with the piggyBac transposable element.

    Science.gov (United States)

    Rodrigues, Flávia Guimarães; Oliveira, Sabrina Barbosa; Rocha, Bruno Coelho; Moreira, Luciano Andrade

    2006-11-01

    The technique to generate transgenic mosquitoes requires adaptation for each target species because of aspects related to species biology, sensitivity to manipulation and rearing conditions. Here we tested different parameters on the microinjection procedure in order to obtain a transgenic Neotropical mosquito species. By using a transposon-based strategy we were able to successfully transform Aedes fluviatilis (Lutz), which can be used as an avian malaria model. These results demonstrate the usefulness of the piggyBac transposable element as a transformation vector for Neotropical mosquito species and opens up new research frontiers for South American mosquito vectors. PMID:17160283

  2. Germline transformation of Aedes fluviatilis (Diptera:Culicidae with the piggyBac transposable element

    Directory of Open Access Journals (Sweden)

    Flávia Guimarães Rodrigues

    2006-11-01

    Full Text Available The technique to generate transgenic mosquitoes requires adaptation for each target species because of aspects related to species biology, sensitivity to manipulation and rearing conditions. Here we tested different parameters on the microinjection procedure in order to obtain a transgenic Neotropical mosquito species. By using a transposon-based strategy we were able to successfully transform Aedes fluviatilis (Lutz, which can be used as an avian malaria model. These results demonstrate the usefulness of the piggyBac transposable element as a transformation vector for Neotropical mosquito species and opens up new research frontiers for South American mosquito vectors.

  3. 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.

  4. Aedes aegypti Control Strategies in Brazil: Incorporation of New Technologies to Overcome the Persistence of Dengue Epidemics

    OpenAIRE

    Helena R. C. Araújo; Carvalho, Danilo O.; Ioshino, Rafaella S.; Costa-da-Silva, André L.; Capurro, Margareth L.

    2015-01-01

    Dengue is considered to be the most important mosquito-borne viral disease in the world. The Aedes aegypti mosquito, its vector, is highly anthropophilic and is very well adapted to urban environments. Although several vaccine candidates are in advanced stages of development no licensed dengue vaccine is yet available. As a result, controlling the spread of dengue still requires that mosquitoes be targeted directly. We review the current methods of dengue vector control focusing on recent tec...

  5. 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...

  6. How dengue vector Aedes albopictus (Diptera: Culicidae survive during the dry season in Dhaka City, Bangladesh?

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    Rajib Chowdhury

    2014-08-01

    Full Text Available Background & objectives: In 2000, a dengue outbreak occurred in Bangladesh that included Dhaka City. Both dengue vectors, Aedes aegypti and Ae. albopictus are present in Bangladesh. Aedes aegypti mosquitoes mainly breed in and around houses and Ae. albopictus is an outside breeder. There are many old trees throughout Dhaka City in different parks, streets and the university campus which may have holes that can contribute as potential breeding habitat for the dengue vector. Therefore, a survey was conducted to investigate the presence of eggs of the dengue vector mosquitoes in treeholes during the dry season in February 2001 to know their contribution on dengue outbreaks. Methods: All treeholes in 10 different localities (parks, streets and university campus of Dhaka City were surveyed. All trees were examined for treeholes up to the height of approximately 3 m and sampled. Debris were collected and packed in poly bags and brought to the laboratory for detailed studies. These were then soaked with tap water to observe egg hatching. The soaked materials were kept up to 20 days covered by a fine mosquito net. After 2-3 days, the eggs started hatching and larvae were separated from the sample for rearing up to IV instar. Results: A total of 245 treeholes were surveyed in 49 identified tree species and 18 unidentified trees. Altogether, 1365 Aedes larvae were found, of which 1096 were Aedes albopictus and 269 were other Aedes species. The largest number of larvae was observed in Delonix regia of Leguminosae family. The number of Aedes albopictus found in the treeholes have perfect positive correlation with the number of other Aedes species. Not a single egg of Aedes aegypti was found in this survey. Interpretation & conclusion: This information will inform public health workers as well as the national control programme to help to solve mosquito borne diseases specially that of dengue. This is critical in planning for vector control operations due to

  7. 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

    OpenAIRE

    Tsunoda Takashi; Kawada Hitoshi; Huynh Trang TT; Le Luu Loan; Le San Hoang; Tran Huu Ngoc; Vu Huong Thi Que; Le Hieu Minh; Hasebe Futoshi; Tsuzuki Ataru; Takagi Masahiro

    2013-01-01

    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...

  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

    OpenAIRE

    Tsunoda, Takashi; Kawada, Hitoshi; Huynh, Trang TT; Le Luu, Loan; Le, San Hoang; Tran, Huu Ngoc; Vu, Huong Thi Que; Le, Hieu Minh; Hasebe, Futoshi; Tsuzuki, Ataru; Takagi, Masahiro

    2013-01-01

    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 aegyp...

  9. Mosquito surveillance revealed lagged effects of mosquito abundance on mosquito-borne disease transmission: a retrospective study in Zhejiang, China.

    Science.gov (United States)

    Guo, Song; Ling, Feng; Hou, Juan; Wang, Jinna; Fu, Guiming; Gong, Zhenyu

    2014-01-01

    Mosquito-borne diseases (MBDs) are still threats to public health in Zhejiang. In this study, the associations between the time-lagged mosquito capture data and MBDs incidence over five years were used to examine the potential effects of mosquito abundance on patterns of MBDs epidemiology in Zhejiang during 2008-2012. Light traps were used to collect adult mosquitoes at 11 cities. Correlation tests with and without time lag were performed to investigate the correlations between MBDs incidence rates and mosquito abundance by month. Selected MBDs consisted of Japanese encephalitis (JE), dengue fever (DF) and malaria. A Poisson regression analysis was performed by using a generalized estimating equations (GEE) approach, and the most parsimonious model was selected based on the quasi-likelihood based information criterion (QICu). We identified five mosquito species and the constituent ratio of Culex pipiens pallens, Culex tritaeniorhynchus, Aedes albopictus, Anopheles sinensis and Armigeres subalbatus was 66.73%, 21.47%, 6.72%, 2.83% and 2.25%, respectively. The correlation analysis without and with time lag showed that Culex mosquito abundance at a lag of 0 or 1 month was positively correlated with JE incidence during 2008-2012, Ae. albopictus abundance at a lag of 1 month was positively correlated with DF incidence in 2009, and An. sinensis abundance at a lag of 0-2 months was positively correlated with malaria incidence during 2008-2010. The Poisson regression analysis showed each 0.1 rise of monthly mosquito abundance corresponded to a positive increase of MBD cases for the period of 2008-2012. The rise of mosquito abundance with a lag of 0-2 months increased the risk of human MBDs infection in Zhejiang. Our study provides evidence that mosquito monitoring could be a useful early warning tool for the occurrence and transmission of MBDs. PMID:25393834

  10. Mosquito surveillance revealed lagged effects of mosquito abundance on mosquito-borne disease transmission: a retrospective study in Zhejiang, China.

    Directory of Open Access Journals (Sweden)

    Song Guo

    Full Text Available Mosquito-borne diseases (MBDs are still threats to public health in Zhejiang. In this study, the associations between the time-lagged mosquito capture data and MBDs incidence over five years were used to examine the potential effects of mosquito abundance on patterns of MBDs epidemiology in Zhejiang during 2008-2012. Light traps were used to collect adult mosquitoes at 11 cities. Correlation tests with and without time lag were performed to investigate the correlations between MBDs incidence rates and mosquito abundance by month. Selected MBDs consisted of Japanese encephalitis (JE, dengue fever (DF and malaria. A Poisson regression analysis was performed by using a generalized estimating equations (GEE approach, and the most parsimonious model was selected based on the quasi-likelihood based information criterion (QICu. We identified five mosquito species and the constituent ratio of Culex pipiens pallens, Culex tritaeniorhynchus, Aedes albopictus, Anopheles sinensis and Armigeres subalbatus was 66.73%, 21.47%, 6.72%, 2.83% and 2.25%, respectively. The correlation analysis without and with time lag showed that Culex mosquito abundance at a lag of 0 or 1 month was positively correlated with JE incidence during 2008-2012, Ae. albopictus abundance at a lag of 1 month was positively correlated with DF incidence in 2009, and An. sinensis abundance at a lag of 0-2 months was positively correlated with malaria incidence during 2008-2010. The Poisson regression analysis showed each 0.1 rise of monthly mosquito abundance corresponded to a positive increase of MBD cases for the period of 2008-2012. The rise of mosquito abundance with a lag of 0-2 months increased the risk of human MBDs infection in Zhejiang. Our study provides evidence that mosquito monitoring could be a useful early warning tool for the occurrence and transmission of MBDs.

  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. Morphometric Wing Characters as a Tool for Mosquito Identification.

    Science.gov (United States)

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

    2016-01-01

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

  13. 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

    Directory of Open Access Journals (Sweden)

    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

  14. 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

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

    Science.gov (United States)

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

    2016-01-01

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

  16. First molecular identification of Dirofilaria spp. (Onchocercidae) in mosquitoes from Serbia.

    Science.gov (United States)

    Kurucz, Kornélia; Kepner, Anett; Krtinic, Bosiljka; Zana, Brigitta; Földes, Fanni; Bányai, Krisztián; Oldal, Miklós; Jakab, Ferenc; Kemenesi, Gábor

    2016-08-01

    Dirofilariosis is a common and widespread veterinary health issue in several European countries with notable zoonotic potential. The causative agents are Dirofilaria immitis and Dirofilaria repens nematoda species which are transmitted by different mosquito vectors. Similar to other mosquito-borne infections, the knowledge about mosquito species involved in disease transmission is crucial for the complex understanding of local transmission cycles. Since there is no available data on mosquito species, potentially involved in disease transmission from Serbia, 6369 female mosquito individuals were retrospectively tested for Dirofilaria nematodes, collected from 13 localities in Vojvodina province, Serbia, in 2013. Altogether, 8.33 % of tested pools showed positivity, composed of five mosquito species, mainly, Culex pipiens and Aedes vexans. D. immitis and D. repens were both detected from multiple localities, during the whole period of mosquito breeding season, which provides the first data on local transmission characteristics regarding mosquitoes from the Balkans. PMID:27193348

  17. West Nile Virus Viremia in Eastern Chipmunks (Tamias striatus) Sufficient for Infecting Different Mosquitoes

    OpenAIRE

    Platt, Kenneth B.; Tucker, Bradley J.; Halbur, Patrick G.; Tiawsirisup, Sonthaya; Blitvich, Bradley J; Fabiosa, Flor G.; BARTHOLOMAY, LYRIC C.; Rowley, Wayne A.

    2007-01-01

    In eastern chipmunks (Tamias striatus) inoculated intramuscularly with 101.5 to 105.7 PFU of West Nile virus (WNV), serum titers developed sufficient to infect Aedes triseriatus (Say), Ae. vexans (Meigen), and Culex pipiens (L.). Mean titers (95% confidence interval) of 8 chipmunks were 103.9(3.3–4.5), 106.7(6.4–7.0), and 105.8(4.1–7.5) PFU/mL on days 1–3 postinoculation (p.i.) and 105.8 PFU/mL in 1 chipmunk on day 4 p.i. Mean estimated days that WNV titers were >104.8 and >105.6 were 1.7 (1....

  18. Sampling of adult mosquito vectors with Mosquito Magnet Pro in Panaji, Goa, India.

    Science.gov (United States)

    Korgaonkar, Nandini S; Kumar, Ashwani; Yadav, Rajpal S; Kabadi, Dipak; Dash, Aditya P

    2008-12-01

    For mosquito vector population monitoring, a new commercial trap, Mosquito Magnet Pro (MM-PRO), was tested for its usefulness in Goa, India. Anopheles stephensi was tested for the presence of Plasmodium sporozoite infection in the salivary glands. Using the MM-PRO 24 h a day for 34 days, 2,329 mosquitoes belonging to 16 species were collected. These included 6 species each of the genera Anopheles and Culex, 2 species of Aedes, and 1 each of Mansonia and Armigeres. Most (91%) of the mosquitoes caught were females. Among these the number and percentage of each species were Anopheles stephensi 59 (2.78%), Culex quinquefasciatus 1013 (47.78%), Culex vishnui 551 (26.0%), Mansonia uniformis 216 (10.19%), and Aedes albopictus 1 (0.04%). Of the 54 An. stephensi females tested for the presence of circumsporozoite protein (CSP) by an ELISA technique, 1 was found to be Plasmodium falciparum CSP positive. The MM-PRO device was found useful for mosquito population sampling in the urban setting of Goa. PMID:19181075

  19. 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.

  20. 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.

  1. Seasonal monitoring of Aedes albopictus: practical applications and outcomes

    OpenAIRE

    Stefano Gavaudan; Anna Duranti; Francesca Barchiesi; Sara Ruschioni; Elisa Antognini; Erica Calandri; Paolo Mancini; Paola Riolo

    2014-01-01

    The introduction of the Asian tiger mosquito Aedes (Stegomya) albopictus (Diptera: Culicidae) into temperate regions poses serious concerns for the risk of the spreading of arboviral epidemics, as confirmed by the Chikungunya fever outbreak in Italy. This article describes the implementation and the results of a strategy for the pest management implemented over 4 years in Pesaro (a city in the Marche region, Italy). The strategy used 60 integrated wide‑sized ovitraps for monitoring purposes. ...

  2. Ecology of mosquitoes of Midwestern Nigeria

    Directory of Open Access Journals (Sweden)

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

    2005-03-01

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

  3. 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...

  4. Validation of Aedes aegypti Aag-2 cells as a model for insect immune studies

    OpenAIRE

    Barletta Ana; Silva Maria Clara L Nascimento; Sorgine Marcos

    2012-01-01

    Abstract Background The understanding of mosquito immune responses can provide valuable tools for development of novel mosquito control strategies. Aiming the study at insect innate immunity, continuous insect cell lines have been established and used as research tools due to the fact that they constitute more homogeneous, sensitive, and reproducible systems than the insects from which they originated. More recently, Aag-2, an Aedes aegypti cell lineage, began to be frequently used as a model...

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

    OpenAIRE

    Ricardo Lourenço-de-Oliveira; Marie Vazeille; Ana Maria Bispo de Filippis; Anna-Bella Failloux

    2002-01-01

    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 cyc...

  6. The role of environmental variables on Aedes albopictus biology and chikungunya epidemiology

    OpenAIRE

    Waldock, Joanna; Chandra, Nastassya L.; Lelieveld, Jos; Proestos, Yiannis; Michael, Edwin; Christophides, George; Parham, Paul E

    2013-01-01

    Aedes albopictus is a vector of dengue and chikungunya viruses in the field, along with around 24 additional arboviruses under laboratory conditions. As an invasive mosquito species, Ae. albopictus has been expanding in geographical range over the past 20 years, although the poleward extent of mosquito populations is limited by winter temperatures. Nonetheless, population densities depend on environmental conditions and since global climate change projections indicate increasing temperatures ...

  7. 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.

  8. 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...

  9. Tackling the growing threat of dengue: Phyllanthus niruri-mediated synthesis of silver nanoparticles and their mosquitocidal properties against the dengue vector Aedes aegypti (Diptera: Culicidae)

    Science.gov (United States)

    Mosquitoes transmit pathogens that cause millions of human deaths each year. Dengue virus is transmitted to humans in tropical and subtropical areas by Aedes aegypti (Diptera: Culicidae). The use of synthetic insecticides to control this mosquito is accompanied by high operational costs and adverse...

  10. Aedes albopictus em área rural do Brasil e implicações na transmissão de febre amarela silvestre Aedes albopictus in rural zone of Brazil and its implication in the sylvatic yellow fever transmission

    Directory of Open Access Journals (Sweden)

    Almério de Castro Gomes

    1999-02-01

    Full Text Available Durante estudos ecológicos sobre mosquitos anofelíneos no município de Bataguassu, Estado de Mato Grosso do Sul, foram encontradas larvas e adultos de Aedes albopictus. Pela primeira vez sua introdução ocorre numa área enzoótica do vírus selvático da febre amarela no Brasil. Isto sugere risco potencial para transferência desse vírus para área urbana infestada com Aedes aegypti.Larvae and adult forms of Aedes albopictus were found during ecological study of anopheline mosquitos in the rural zone of the state of Mato Grosso do Sul in Brazil. This occurrence was registered, for the first time in Brazil, in an enzoootic area if sylvatic yellow fever virus. This implies a potential risk of the transfer of this virus to an urban area infested with Aedes aegypti.

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

    Science.gov (United States)

    Wilke, André Barretto Bruno; Marrelli, Mauro Toledo

    2015-01-01

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

  12. Transmission of tularemia from a water source by transstadial maintenance in a mosquito vector

    Science.gov (United States)

    Bäckman, Stina; Näslund, Jonas; Forsman, Mats; Thelaus, Johanna

    2015-01-01

    Mosquitoes are thought to function as mechanical vectors of Francisella tularensis subspecies holarctica (F. t. holarctica) causing tularemia in humans. We investigated the clinical relevance of transstadially maintained F. t. holarctica in mosquitoes. Aedes egypti larvae exposed to a fully virulent F. t. holarctica strain for 24 hours, were allowed to develop into adults when they were individually homogenized. Approximately 24% of the homogenates tested positive for F. t. DNA in PCR. Mice injected with the mosquito homogenates acquired tularemia within 5 days. This novel finding demonstrates the possibility of transmission of bacteria by adult mosquitoes having acquired the pathogen from their aquatic larval habitats.

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

    Science.gov (United States)

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

    2015-06-01

    The flood plains of the Upper Rhine Valley provide excellent conditions for the proliferation of mosquitoes as well as for the development of dragon and damselflies. It could be assumed that mosquitoes belong to the diet of the Odonata and that the latter could be harmed by the reduction of the mosquito population with the purpose of diminishing the massive nuisance for the people living there. A total of 41 adult dragonflies and damselflies were examined by immunoblot for remnants of mosquitoes in their guts. A rabbit antiserum against Aedes vexans proteins was used for the immunoblot. Only 3 Aeshna cyanea and 1 Platycnemis pennipes could be shown to have fed on mosquitoes. In specimens of the genus Sympetrum no mosquitoes were detected. It seems very doubtful that mosquitoes are an essential part of the Odonata diet. PMID:26181697

  14. Aedes albopictus and the reemergence of Dengue

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    Rezza Giovanni

    2012-01-01

    Full Text Available Abstract Dengue is a vector-borne disease that is estimated to affect millions of individuals each year in tropical and subtropical areas, and it is reemerging in areas that have been disease-free for relatively long periods of time. In this issue of the journal, Peng et al. report on a Dengue outbreak in a city in southern China that had been disease-free for more than two decades. The infection, which was due to serotype 1, was introduced by a traveler from South-east Asia and transmitted by Aedes albopictus, the Asian tiger mosquito. Compared to Aedes aegypti, which is the most important vector of Dengue, Ae albopictus is a less competent vector of arboviruses, and the epidemics it causes are milder. However, Ae albopictus is becoming an increasingly important vector because of its rapidly changing global distribution. In particular, the worldwide trade in second hand tires, which often contain water and are an ideal place for eggs and larvae, has been a key factor in the large-scale conquest of Ae albopictus, which easily adapts to new environments, even in a temperate climate. This expansion is creating new opportunities for viruses to circulate in new areas, becoming a common cause of epidemics in Ae aegypti-free countries, from Hawaii to Mauritius. The outbreak in China, like similar events, was mild and short-lived. Because epidemics due to Ae albopictus are milder, the replacement of Ae aegypti with the tiger mosquito could even result in public-health benefits. However, there is no solid evidence of this, and the milder course of the outbreak could be in part explained by the relatively short duration of the hot season in some affected areas. Since it is almost impossible to prevent Ae albopictus from being introduced in a country, mosquito-control measures at local level remain the most effective means of controlling arbovirus outbreaks.

  15. Zika virus emergence in mosquitoes in southeastern Senegal, 2011.

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    Diawo Diallo

    Full Text Available Zika virus (ZIKV; genus Flavivirus, family Flaviviridae is maintained in a zoonotic cycle between arboreal Aedes spp. mosquitoes and nonhuman primates in African and Asian forests. Spillover into humans has been documented in both regions and the virus is currently responsible for a large outbreak in French Polynesia. ZIKV amplifications are frequent in southeastern Senegal but little is known about their seasonal and spatial dynamics. The aim of this paper is to describe the spatio-temporal patterns of the 2011 ZIKV amplification in southeastern Senegal.Mosquitoes were collected monthly from April to December 2011 except during July. Each evening from 18:00 to 21:00 hrs landing collections were performed by teams of 3 persons working simultaneously in forest (canopy and ground, savannah, agriculture, village (indoor and outdoor and barren land cover sites. Mosquitoes were tested for virus infection by virus isolation and RT-PCR. ZIKV was detected in 31 of the 1,700 mosquito pools (11,247 mosquitoes tested: Ae. furcifer (5, Ae. luteocephalus (5, Ae. africanus (5, Ae. vittatus (3, Ae. taylori, Ae. dalzieli, Ae. hirsutus and Ae. metallicus (2 each and Ae. aegypti, Ae. unilinaetus, Ma. uniformis, Cx. perfuscus and An. coustani (1 pool each collected in June (3, September (10, October (11, November (6 and December (1. ZIKV was detected from mosquitoes collected in all land cover classes except indoor locations within villages. The virus was detected in only one of the ten villages investigated.This ZIKV amplification was widespread in the Kédougou area, involved several mosquito species as probable vectors, and encompassed all investigated land cover classes except indoor locations within villages. Aedes furcifer males and Aedes vittatus were found infected within a village, thus these species are probably involved in the transmission of Zika virus to humans in this environment.

  16. Assessing Seasonal Risks for the Introduction and Mosquito-borne Spread of Zika Virus in Europe

    OpenAIRE

    Rocklöv, Joacim; Quam, Mikkel Brandon; Sudre, Bertrand; German, Matthew; Kraemer, Moritz U G; Brady, Oliver; Bogoch, Isaac I.; Liu-Helmersson, Jing; Wilder-Smith, Annelies; Jan C Semenza; Ong, Mark; Aaslav, Kaja Kaasik; Khan, Kamran

    2016-01-01

    The explosive Zika virus epidemic in the Americas is amplifying spread of this emerging pathogen into previously unaffected regions of the world, including Europe (Gulland, 2016), where local populations are immunologically naïve. As summertime approaches in the northern hemisphere, Aedes mosquitoes in Europe may find suitable climatic conditions to acquire and subsequently transmit Zika virus from viremic travellers to local populations. While Aedes albopictus has proven to be a vector for t...

  17. Superior reproductive success on human blood without sugar is not limited to highly anthropophilic mosquito species

    OpenAIRE

    Braks, M.A.H.; JULIANO, S. A.; LOUNIBOS, L. P.

    2006-01-01

    Anthropophilic mosquitoes such as Aedes aegypti L. (Diptera: Culicidae) have been shown to have superior reproductive success on human blood when sugar is not available. Life-table experiments were conducted with Aedes albopictus Skuse and Ae. aegypti to compare the effects of sugar availability on age-specific survivorship, lifetime and daily fecundity, and blood-feeding frequency when offered human blood daily. There were no significant interactions between the effects of sugar availability...

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

    Directory of Open Access Journals (Sweden)

    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.

  19. 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

  20. 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,

  1. High Resolution Spatial Analysis of Habitat Preference of Aedes Albopictus (Diptera Culicidae) in an Urban Environment

    NARCIS (Netherlands)

    Cianci, Daniela; Hartemink, Nienke; Zeimes, Caroline B; Vanwambeke, Sophie O; Ienco, Annamaria; Caputo, Beniamino

    2015-01-01

    Over the past decades, the Asian tiger mosquito (Aedes albopictus (Skuse, 1895)) has emerged in many countries, and it has colonized new environments, including urban areas. The species is a nuisance and a potential vector of several human pathogens, and a better understanding of the habitat prefere

  2. High Resolution Spatial Analysis of Habitat Preference of Aedes Albopictus (Diptera: Culicidae) in an Urban Environment

    NARCIS (Netherlands)

    D. Cianci; N. Hartemink; C.B. Zeimes; S.O. Vanwambeke; A. Ienco; B. Caputo

    2015-01-01

    Over the past decades, the Asian tiger mosquito (Aedes albopictus (Skuse, 1895)) has emerged in many countries, and it has colonized new environments, including urban areas. The species is a nuisance and a potential vector of several human pathogens, and a better understanding of the habitat prefere

  3. How dengue vector Aedes albopictus (Diptera: Culicidae) survive during the dry season in Dhaka City, Bangladesh?

    OpenAIRE

    Rajib Chowdhury; Vashkar Chowdhury; Shyla Faria; M. Mamun Huda; Runa Laila; Indrani Dhar; Maheswary, Narayan P.; Aditya Prasad Dash

    2014-01-01

    Background & objectives: In 2000, a dengue outbreak occurred in Bangladesh that included Dhaka City. Both dengue vectors, Aedes aegypti and Ae. albopictus are present in Bangladesh. Aedes aegypti mosquitoes mainly breed in and around houses and Ae. albopictus is an outside breeder. There are many old trees throughout Dhaka City in different parks, streets and the university campus which may have holes that can contribute as potential breeding habitat for the dengue vector. Therefore, a survey...

  4. Species diversity of mosquito breeding in rubber plantations of Kerala, India.

    Science.gov (United States)

    Sumodan, P K

    2012-06-01

    During south-west monsoon season, rubber plantations in Kerala have been found to provide ideal conditions for the proliferation of mosquitoes. In a study conducted from June 2005 to September 2010 in Kannur, Wayanad, and Kozhikode districts, 12 species of mosquitoes in 6 genera--Aedes, Armigeres, Culex, Heizmannia, Toxorhynchites, and Verrallina--were found to breed in rain water-filled cups used for collecting rubber latex. The only vector species found was Aedes albopictus, known for its ability to transmit dengue and chikungunya. The combinations of species found associated in the latex cups is also presented. PMID:22894122

  5. 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.

  6. 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

  7. Successful overwintering of Aedes albopictus in Germany.

    Science.gov (United States)

    Pluskota, Björn; Jöst, Artur; Augsten, Xenia; Stelzner, Lilith; Ferstl, Ina; Becker, Norbert

    2016-08-01

    The Asian tiger mosquito (Aedes albopictus) is of great concern to public health authorities due to its vector competence and rapid spread across the globe. In 2015, two large local breeding populations of Ae. albopictus were discovered in southwest Germany. In spring 2016, we were able to demonstrate the first evidence of a successful overwintering in Germany of this originally tropical mosquito species in different research projects. Particularly noteworthy is the successful hatching of diapause eggs of an Italian strain (Calabria), which overwintered successfully in the field in St. Georgen im Schwarzwald (Baden-Wuerttemberg) at 820 m above sea level. Furthermore, within the scope of a larvae monitoring, the first larvae that hatched in the field were detected on the April 09, 2016 in a rain barrel within the Heidelberg population. Our first results show that self-extinction due to an unsuccessful overwintering cannot be assumed for populations of the Asian tiger mosquito which settled in Germany in previous years. The evidence of a successful overwintering of a large number of diapause eggs and the hatching of the first larvae in field conditions opens the control year against Ae. albopictus in southwest Germany. PMID:27112761

  8. Zika virus in Gabon (Central Africa--2007: a new threat from Aedes albopictus?

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    Gilda Grard

    2014-02-01

    Full Text Available Chikungunya and dengue viruses emerged in Gabon in 2007, with large outbreaks primarily affecting the capital Libreville and several northern towns. Both viruses subsequently spread to the south-east of the country, with new outbreaks occurring in 2010. The mosquito species Aedes albopictus, that was known as a secondary vector for both viruses, recently invaded the country and was the primary vector involved in the Gabonese outbreaks. We conducted a retrospective study of human sera and mosquitoes collected in Gabon from 2007 to 2010, in order to identify other circulating arboviruses.Sample collections, including 4312 sera from patients presenting with painful febrile disease, and 4665 mosquitoes belonging to 9 species, split into 247 pools (including 137 pools of Aedes albopictus, were screened with molecular biology methods. Five human sera and two Aedes albopictus pools, all sampled in an urban setting during the 2007 outbreak, were positive for the flavivirus Zika (ZIKV. The ratio of Aedes albopictus pools positive for ZIKV was similar to that positive for dengue virus during the concomitant dengue outbreak suggesting similar mosquito infection rates and, presumably, underlying a human ZIKV outbreak. ZIKV sequences from the envelope and NS3 genes were amplified from a human serum sample. Phylogenetic analysis placed the Gabonese ZIKV at a basal position in the African lineage, pointing to ancestral genetic diversification and spread.We provide the first direct evidence of human ZIKV infections in Gabon, and its first occurrence in the Asian tiger mosquito, Aedes albopictus. These data reveal an unusual natural life cycle for this virus, occurring in an urban environment, and potentially representing a new emerging threat due to this novel association with a highly invasive vector whose geographic range is still expanding across the globe.

  9. The further spread of Aedes japonicus japonicus (Diptera, Culicidae) towards northern Germany.

    Science.gov (United States)

    Werner, Doreen; Kampen, Helge

    2013-10-01

    After its first detection in 2008 in the south German federal state of Baden-Wuerttemberg, another distinct population of the invasive Asian bush mosquito Aedes japonicus japonicus was unexpectedly found in western Germany in 2012. Range expansion had already been observed for the southern German population and was anticipated for the western German one. Here, we report on a third, apparently independent and even more northerly German colonization area of Aedes j. japonicus in southern Lower Saxony and northeastern North Rhine-Westphalia, which was discovered in spring 2013. In a snapshot study, intended to determine the presence or absence of Aedes j. japonicus in an area close to Hanover, the capital of the northern German federal state of Lower Saxony, where a specimen had been collected in late 2012, central water basins of cemeteries were checked for pre-imaginal mosquito stages at the beginning of the mosquito season 2013. Almost 20% of the inspected cemeteries were found positive (25 out of 129), with many of them being located in towns and villages close to the motorways A2 and A7. Being of Far Eastern origin, the Asian bush mosquito is well adapted to moderate climates and appears to be further expanding its distribution area in Central Europe. As it is a proven laboratory vector of several mosquito-borne disease agents, its present and future distribution areas should be carefully monitored. PMID:23974325

  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. The wMelPop strain of Wolbachia interferes with dopamine levels in Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Eyles Darryl W

    2011-02-01

    Full Text Available Abstract Wolbachia is an intracellular bacterium that has been stably transinfected into the mosquito vector of dengue, Aedes aegypti. This inherited infection causes a range of metabolic and phenotypic alterations in the mosquito, which might be related to neuronal abnormalities. In order to determine if these alterations were caused by the manipulation of neuroamines by this bacterium, we studied the expression of genes involved in the dopamine biosynthetic pathway and also measured the amount of dopamine in infected and uninfected mosquitoes of different ages. Wolbachia-infected mosquitoes exhibit greater expression of some genes related to the melanization pathway, but not for those directly linked to dopamine production. Although dopamine levels were higher in Wolbachia-positive mosquitoes this was not consistent across all insect ages nor was it related to the previously described Wolbachia induced "bendy" and "shaky" phenotypes.

  12. Evaluation of Mosquito Repellent Activity of Isolated Oleic Acid, Eicosyl Ester from Thalictrum javanicum

    OpenAIRE

    Abinaya Gurunathan; Jamuna Senguttuvan; S Paulsamy

    2016-01-01

    To evaluate the traditional use, the mosquito repellent property of Thalictrum javanicum and to confirm the predicted larvicidal activity of the isolated compound, oleic acid, eicosyl ester from its aerial parts by PASS software, the present study was carried out using 4th instar stage larvae of the mosquitoes, Aedes aegypti (dengue vector) and Culex quinquefasciatus (filarial vector). Insecticidal susceptibility tests were conducted and the mortality rate was observed after 24 h exposure. Th...

  13. Comparative Susceptibility of Mosquito Populations in North Queensland, Australia to Oral Infection with Dengue Virus

    OpenAIRE

    Ye, Yixin H; Ng, Tat Siong; Frentiu, Francesca D.; Walker, Thomas; van den Hurk, Andrew F.; O' Neill, Scott L; Beebe, Nigel W; McGraw, Elizabeth A.

    2014-01-01

    Dengue is the most prevalent arthropod-borne virus, with at least 40% of the world's population at risk of infection each year. In Australia, dengue is not endemic, but viremic travelers trigger outbreaks involving hundreds of cases. We compared the susceptibility of Aedes aegypti mosquitoes from two geographically isolated populations to two strains of dengue virus serotype 2. We found, interestingly, that mosquitoes from a city with no history of dengue were more susceptible to virus than m...

  14. Extensive circadian and light regulation of the transcriptome in the malaria mosquito Anopheles gambiae

    OpenAIRE

    Rund, Samuel SC; James E. Gentile; Duffield, Giles E.

    2013-01-01

    Background Mosquitoes exhibit 24 hr rhythms in flight activity, feeding, reproduction and development. To better understand the molecular basis for these rhythms in the nocturnal malaria vector Anopheles gambiae, we have utilized microarray analysis on time-of-day specific collections of mosquitoes over 48 hr to explore the coregulation of gene expression rhythms by the circadian clock and light, and compare these with the 24 hr rhythmic gene expression in the diurnal Aedes aegypti dengue vec...

  15. Experimental investigation of the susceptibility of Italian Culex pipiens mosquitoes to Zika virus infection.

    Science.gov (United States)

    Boccolini, Daniela; Toma, Luciano; Di Luca, Marco; Severini, Francesco; Romi, R; Remoli, Maria Elena; Sabbatucci, Michela; Venturi, Giulietta; Rezza, Giovanni; Fortuna, Claudia

    2016-09-01

    We investigated the susceptibility of an Italian population of Culex pipiens mosquitoes to Zika virus (ZIKV) infection, tested in parallel with Aedes aegypti, as a positive control. We analysed mosquitoes at 0, 3, 7, 10, 14, 20 and 24 days after an infectious blood meal. Viral RNA was detected in the body of Cx. pipiens up to three days post-infection, but not at later time points. Our results indicate that Cx. pipiens is not susceptible to ZIKV infection. PMID:27605056

  16. Genes and Odors Underlying the Recent Evolution of Mosquito Preference for Humans.

    Science.gov (United States)

    McBride, Carolyn S

    2016-01-11

    Mosquito species that specialize in biting humans are few but dangerous. They include the African malaria vectors Anopheles gambiae and Anopheles coluzzii, as well as Aedes aegypti, the cosmopolitan vector of dengue, chikungunya, and yellow fever. These mosquitoes have evolved a remarkable innate preference for human odor that helps them find and bite us. Here I review what is known about this important evolutionary adaptation, from its historical documentation to its chemical and molecular basis. PMID:26766234

  17. An optimal control model of mosquito reduction management in a dengue endemic region

    OpenAIRE

    Wijaya, Karunia Putra; Goetz, Thomas; Soewono, Edy

    2015-01-01

    Aedes aegypti is known as the responsible vector in transmitting dengue flavivirus. Unavailability of medication to cure the transmission in human blood becomes a global health issue in recent decades. World epidemiologists are encouraged to focus on inves- tigation toward an effective and inexpensive way to prevent dengue transmission, i.e. mosquito control. In this paper, we present a model depicting the dynamics of mosquito population based on indoor-outdoor life cycle classification. The ...

  18. Foraging Ranges of Insectivorous Bats Shift Relative to Changes in Mosquito Abundance

    OpenAIRE

    Leroy Gonsalves; Brad Law; Cameron Webb; Vaughan Monamy

    2013-01-01

    The need to develop effective management strategies for insectivorous bat populations requires an understanding of factors influencing habitat use. Availability of pest prey, such as mosquitoes is likely to be one such factor. To assess whether this is the case, we radio-tracked Vespadelus vulturnus Thomas (little forest bat), a predator of Aedes vigilax Skuse (saltmarsh mosquito), in saltmarsh and adjacent coastal swamp forest during periods of high and low Ae. vigilax abundance. When mosqui...

  19. A device for monitoring and control of mosquitoes by behaviour manipulation.

    Science.gov (United States)

    Vartak, P H; Tungikar, V B; Sharma, R N

    1994-09-01

    A trap was designed and fabricated for capturing mosquito larvae based on their behavioural responses to food and light. The larvae upon entering the trap died ultimately due to asphyxiation. Maximum success was achieved with Aedes aegypti larvae in lesser water volumes. The usefulness of the device for studying the response of mosquito larvae and aquatic organisms to chemicals, baits, light, various stimuli and possible pest/vector monitoring and management in aquatic eco-system is discussed. PMID:7814048

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

    Science.gov (United States)

    Berec, Ludĕk; Gelbic, Ivan; Sebesta, Oldrich

    2014-01-01

    An understanding of how climate variables drive seasonal dynamics of mosquito populations is critical to mitigating negative impacts of potential outbreaks, including both nuisance effects and risk of mosquito-borne infectious disease. Here, we identify climate variables most affecting seasonal dynamics of two major floodwater mosquitoes, Aedes vexans (Meigen, 1830) and Aedes sticticus (Meigen, 1838) (Diptera: Culicidae), along the lower courses of the Dyje River, at the border between the Czech Republic and Austria. Monthly trap counts of both floodwater mosquitoes varied both across sites and years. Despite this variability, both models used to fit the observed data at all sites (and especially that for Ae. sticticus) and site-specific models fitted the observed data quite well. The most important climate variables we identified-temperature and especially flooding-were driving seasonal dynamics of both Aedes species. We suggest that flooding determines seasonal peaks in the monthly mosquito trap counts while temperature modulates seasonality in these counts. Hence, floodwater mosquitoes indeed appear worthy of their name. Moreover, the climate variables we considered for modeling were able reasonably to predict mosquito trap counts in the month ahead. Our study can help in planning flood management; timely notification of people, given that these mosquitoes are a real nuisance in this region; public health policy management to mitigate risk from such mosquito-borne diseases as that caused in humans by the Tahyna virus; and anticipating negative consequences of climate change, which are expected only to worsen unless floods, or the mosquitoes themselves, are satisfactorily managed. PMID:24605456

  1. Bloodmeal microfilariae density and the uptake and establishment of Wuchereria bancrofti infections in Culex quinquefasciatus and Aedes aegypti

    OpenAIRE

    Albuquerque Cleide MR; Cavalcanti Vânia MS; Melo Maria Alice V; Verçosa Paulo; Regis Lêda N; Hurd Hilary

    1999-01-01

    The relationship between ingestion of microfilariae (mf), production of infective larvae (L3) and mf density in human blood has been suggested as an important determinant in the transmission dynamics of lymphatic filariasis. Here we assess the role of these factors in determining the competence of a natural vector Culex quinquefasciatus and a non vector Aedes aegypti to transmit Wuchereria bancrofti. Mosquitoes were infected via a membrane feeding procedure. Both mosquito species ingested mor...

  2. Wolbachia Density and Cytoplasmic Incompatibility in Aedes albopictus: Concerns with Using Artificial Wolbachia Infection as a Vector Suppression Tool

    OpenAIRE

    Maurizio Calvitti; Francesca Marini; Angiola Desiderio; Arianna Puggioli; Riccardo Moretti

    2015-01-01

    The mosquito Aedes albopictusi is a competent vector of harmful human pathogens, including viruses causing dengue and chikungunya. Cytoplasmic incompatibility (CI) induced by endosymbiotic Wolbachia can be used to produce functionally sterile males that can be released in the field as a suppression tool against this mosquito. Because the available sexing methods are not efficient enough to avoid unintentional release of a few transinfected females, we assessed the CI pattern in crosses betwee...

  3. Effect of Larval Competition on Extrinsic Incubation Period and Vectorial Capacity of Aedes albopictus for Dengue Virus

    OpenAIRE

    Bara, Jeffrey; Rapti, Zoi; Cáceres, Carla E.; Muturi, Ephantus J.

    2015-01-01

    Despite the growing awareness that larval competition can influence adult mosquito life history traits including susceptibility to pathogens, the net effect of larval competition on human risk of exposure to mosquito-borne pathogens remains poorly understood. We examined how intraspecific larval competition affects dengue-2 virus (DENV-2) extrinsic incubation period and vectorial capacity of its natural vector Aedes albopictus. Adult Ae. albopictus from low and high-larval density conditions ...

  4. The significance of ratios of detritus types and micro-organism productivity to competitive interactions between aquatic insect detritivores

    OpenAIRE

    YEE, DONALD A.; Kaufman, Michael G.; Juliano, Steven A.

    2007-01-01

    Investigations of competitive interactions emphasize non-detrital resources, even though detritus is a major component of most food webs. Studies of competing species focus usually on single resource types, although consumers in nature are likely to encounter mixtures of resource types that may affect whether competition results in exclusion or coexistence.The invasive mosquito Aedes albopictus is capable of excluding the native mosquito Ochlerotatus triseriatus in competition for single detr...

  5. Larvicidal and Adulticidal Activity of Chroman and Chromene Analogues against Susceptible and Permethrin-Resistant Mosquito Strains.

    Science.gov (United States)

    Meepagala, Kumudini M; Estep, Alden S; Becnel, James J

    2016-06-22

    Mosquitoes play a major role as vectors that transmit parasitic and viral diseases worldwide, especially in tropical and subtropical countries. Mosquito borne diseases not only affect humans but they also affect livestock in many parts of the world. They carry diseases that are lethal to dogs and horses. Dog heartworm disease (Dirofilaria immitis) is a parasitic disease spread through mosquitoes. This disease is not limited to dogs, but it can affect other animals and humans as well. Eastern equine encephalitis (EEE) and West Nile virus (WNV) are also mosquito borne diseases that affect the central nervous system of horses and cause severe complications and death. Emergence of resistance among mosquitoes to current pesticides has increased the importance of the search for alternate compounds that are effective and environmentally benign with diverse modes of actions than those that are commercially available. Aedes aegypti mosquitoes are the primary vector for transmission of Zika viral fever, yellow fever, dengue fever, and chikungunya. Mosquito control is currently the best strategy to prevent mosquito borne diseases. There are numerous approaches for control of potentially dangerous mosquito populations. These approaches include the use of adulticides (insecticides), larvicides, and, to a limited extent, the use of repellents. Our previous studies have shown the mosquito repellent activity of chromenes. In the present study, we demonstrate larvicidal and adulticidal activity of chroman and chromene analogues against a permethrin susceptible laboratory strain as well as activity against a permethrin-resistant strain of Aedes aegypti. PMID:27249182

  6. Potential for Extrinsic Incubation Temperature to Alter Interplay Between Transmission Potential and Mortality of Dengue-Infected Aedes aegypti

    Science.gov (United States)

    Christofferson, Rebecca C.; Mores, Christopher N.

    2016-01-01

    The extrinsic incubation period is a critical component in the assessment of arboviral transmission potential. It defines the time it takes for a mosquito to become infectious following exposure to an arbovirus. Since this is a temporal process, the lifespan of a mosquito is intimately tied to the extrinsic incubation period and thus transmission potential of these viruses. Temperature is a known effector of both vector competence (the ability of a vector to transmit a pathogen) and mosquito mortality, but the interaction among temperature, vector competence, and mosquito mortality is not well characterized. Herein, we investigate this interaction for dengue virus, serotype 2, and its primary vector Aedes aegypti where we found that at 30 °C, infection and/or dissemination shortened the average lifespan of the mosquito and that when considering only mosquitoes with a disseminated infection, those incubated at 26 °C lived significantly longer.

  7. Potential for Extrinsic Incubation Temperature to Alter Interplay Between Transmission Potential and Mortality of Dengue-Infected Aedes aegypti.

    Science.gov (United States)

    Christofferson, Rebecca C; Mores, Christopher N

    2016-01-01

    The extrinsic incubation period is a critical component in the assessment of arboviral transmission potential. It defines the time it takes for a mosquito to become infectious following exposure to an arbovirus. Since this is a temporal process, the lifespan of a mosquito is intimately tied to the extrinsic incubation period and thus transmission potential of these viruses. Temperature is a known effector of both vector competence (the ability of a vector to transmit a pathogen) and mosquito mortality, but the interaction among temperature, vector competence, and mosquito mortality is not well characterized. Herein, we investigate this interaction for dengue virus, serotype 2, and its primary vector Aedes aegypti where we found that at 30 °C, infection and/or dissemination shortened the average lifespan of the mosquito and that when considering only mosquitoes with a disseminated infection, those incubated at 26 °C lived significantly longer. PMID:27478382

  8. Zika Virus Emergence in Mosquitoes in Southeastern Senegal, 2011

    OpenAIRE

    Diallo, Diawo; Sall, Amadou A; Diagne, Cheikh T.; Faye, Oumar; Faye, Ousmane; Ba, Yamar; Hanley, Kathryn A.; Buenemann, Michaela; Weaver, Scott C.; Diallo, Mawlouth

    2014-01-01

    Background Zika virus (ZIKV; genus Flavivirus, family Flaviviridae) is maintained in a zoonotic cycle between arboreal Aedes spp. mosquitoes and nonhuman primates in African and Asian forests. Spillover into humans has been documented in both regions and the virus is currently responsible for a large outbreak in French Polynesia. ZIKV amplifications are frequent in southeastern Senegal but little is known about their seasonal and spatial dynamics. The aim of this paper is to describe the spat...

  9. Alterations in the Aedes aegypti transcriptome during infection with West Nile, dengue and yellow fever viruses.

    Directory of Open Access Journals (Sweden)

    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.

  10. Larval habitats of mosquito fauna in Osogbo metropolis, Southwestern Nigeria

    Institute of Scientific and Technical Information of China (English)

    Monsuru Adebayo Adeleke; Wasiu Olalekan Adebimpe; AbdulWasiu Oladele Hassan; Sunday Olukayode Oladejo; Ismail Olaoye; Ganiyu Olatunji Olatunde; Taiwo Adewole

    2013-01-01

    Objective:To determine the larval habitats of mosquito fauna and possible impact of land use/land cover changes on the epidemiology of mosquito-borne diseases in Osogbo metropolis, Southwestern, Nigeria. Methods: All accessible larval habitats were surveyed between May and September, 2011 in Osogbo metropolis while Land Use/ Land cover of the city was analyzed using 2 Lansat Multispectral Scanner satellite imagery of SPOT 1986 and LANDSAT TM 2009. Results:A total of six species namely, Aedes aegypti, Aedes albopictus, Aedes vittatus, Anopheles gambiae complex, Culex quinquefasciatus and Eretmapodite chrysogaster were encountered during the study. The occurrence and contribution of disused tyres was significantly higher (P0.05). The accessible land use/land covered of the study area between 1986 and 2009 showed that the wet land coverage and settlement area increased from 0.19 to 9.09 hectare and 1.00 to 2.01 hectare respectively while the forest area decreased from 60.18 to 50.14 hectare. Conclusion: The contribution of the habitats coupled with the increasing rate of flooded environment which could provide ample breeding sites for mosquitoes call for sustained environmental sanitation and management in Osogbo metropolis.

  11. The effect of photoperiod on life history and blood-feeding activity in Aedes albopictus and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Costanzo, K S; Schelble, S; Jerz, K; Keenan, M

    2015-06-01

    Several studies have examined how climatic variables such as temperature and precipitation may affect life history traits in mosquitoes that are important to disease transmission. Despite its importance as a seasonal cue in nature, studies investigating the influence of photoperiod on such traits are relatively few. This study aims to investigate how photoperiod alters life history traits, survival, and blood-feeding activity in Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus). We performed three experiments that tested the effects of day length on female survival, development time, adult size, fecundity, adult life span, and propensity to blood feed in Ae. albopictus and Ae. aegypti. Each experiment had three photoperiod treatments: 1) short-day (10L:14D), 2) control (12L:12D), and 3) long-day (14L:10D). Aedes albopictus adult females were consistently larger in size when reared in short-day conditions. Aedes aegypti adult females from short-day treatments lived longer and were more likely to take a blood meal compared to other treatments. We discuss how species-specific responses may reflect alternative strategies evolved to increase survival during unfavorable conditions. We review the potential impacts of these responses on seasonal transmission patterns, such as potentially increasing vectorial capacity of Ae. aegypti during periods of shorter day lengths. PMID:26047197

  12. Towards the genetic manipulation of mosquito disease vectors

    International Nuclear Information System (INIS)

    Our research is aimed at developing the technologies necessary to undertake the genetic manipulation of insect vector genomes. In the longer term, we wish to explore the potential that this technology may have for developing novel strategies for the control of vector-borne diseases. The focus of our current research has been to: i) identify and characterise endogenous transposable elements in the genomes of mosquito vectors -research has focussed on identifying both Class I and Class 11 elements and determining their structure and distribution within mosquito genomes; ii) develop and use transfection systems for mosquito cells in culture as a test bed for transformation vectors and promoters - transfection techniques, vector constructs and different promoters driving reporter genes have been utilised to optimise the transformation of both Aedes aegypti and Anopheles gambiae cells in culture; iii) identify putative promoter sequences which are induced in the female mosquito midgut when it takes a blood meal - the Anopheles gambiae trypsin gene locus has been cloned and sequenced and the intergenic regions assessed for their ability to induce reporter gene expression in mosquito gut cells. The progress we have made in each of these areas will be described and discussed in the context of our longer term aim which is to introduce genes coding for antiparasitic agents into mosquito genomes in such a way that they are expressed in the mosquito midgut and disrupt transmission of the malaria parasite. (author)

  13. Behavioral responses of Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles minimus against various synthetic and natural repellent compounds.

    Science.gov (United States)

    Sathantriphop, Sunaiyana; White, Sabrina A; Achee, Nicole L; Sanguanpong, Unchalee; Chareonviriyaphap, Theeraphap

    2014-12-01

    The behavioral responses of colony populations of Aedes aegypti, Aedes albopictus, Culex quinquefasciatus, and Anopheles minimus to four essential oils (citronella, hairy basil, catnip, and vetiver), two standard repellents (DEET and picaridin), and two synthetic pyrethroids (deltamethrin and permethrin) were conducted in the laboratory using an excito-repellency test system. Results revealed that Cx. quinquefasciatus and An. minimus exhibited much stronger behavioral responses to all test compounds (65-98% escape for contact, 21.4-94.4% escape for non-contact) compared to Ae. aegypti (3.7-72.2% escape (contact), 0-31.7% (non-contact)) and Ae. albopictus (3.5-94.4% escape (contact), 11.2-63.7% (non-contact)). In brief, essential oil from vetiver elicited the greatest irritant responses in Cx. quinquefasciatus (96.6%) and An. minimus (96.5%) compared to the other compounds tested. The synthetic pyrethroids caused a stronger contact irritant response (65-97.8% escape) than non-contact repellents (0-50.8% escape for non-contact) across all four mosquito species. Picaridin had the least effect on all mosquito species. Findings from the current study continue to support the screening of essential oils from various plant sources for protective properties against field mosquitoes. PMID:25424262

  14. Mosquito infection responses to developing filarial worms.

    Directory of Open Access Journals (Sweden)

    Sara M Erickson

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

  15. Host-feeding pattern of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in heterogeneous landscapes of South Andaman, Andaman and Nicobar Islands, India.

    Science.gov (United States)

    Sivan, Arun; Shriram, A N; Sunish, I P; Vidhya, P T

    2015-09-01

    Mosquito foraging behavior is a determinant of host-vector contact and has an impact on the risk of arboviral epidemics. Therefore, blood-feeding patterns is a useful tool for assessing the role in pathogen transmission by vector mosquitoes. Competent vectors of dengue and chikungunya viz. Aedes aegypti and Aedes albopictus are widely prevalent in the Andaman and Nicobar archipelago. Considering the vector potential, medical importance of both these mosquito species and lack of information on host-feeding patterns, blood meal analysis of both these vector mosquitoes was undertaken. Biogents Sentinel traps were used for sampling blooded mosquitoes, for identifying the source of blood meal by agar gel-precipitin test. We identified vertebrate source of 147 and 104 blood meals in Ae. aegypti and Ae. albopictus from heterogeneous landscapes in South Andaman district. Results revealed that Ae. aegypti (88 %) and Ae. albopictus (49 %) fed on human and a small proportion on mammals and fowls, indicative of predominance of anthropophilism. Ae. aegypti predominantly fed on human blood (94.2 %-densely built urban, 89.8 %-low vegetation coverage, and 78.3 %-medium vegetation coverage). Anthropophilism in Ae. albopictus was maximal in densely built urban (90.5 %) and progressively decreased from low vegetation-vegetation/forested continuum (66.7, 36.4, and 8.7 %), indicating plasticity in feeding across these landscapes. Epidemiological significance of the findings is discussed. PMID:26220560

  16. Vector Competence of Aedes aegypti and Aedes vittatus (Diptera: Culicidae) from Senegal and Cape Verde Archipelago for West African Lineages of Chikungunya Virus

    OpenAIRE

    Diagne, Cheikh T.; Faye, Oumar; Guerbois, Mathilde; Knight, Rachel; Diallo, Diawo; Ba, Yamar; Dia, Ibrahima; Faye, Ousmane; Weaver, Scott C.; Sall, Amadou A; Diallo, Mawlouth

    2014-01-01

    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 rev...

  17. Host-pathogen interactions and genome evolution in two generalist and specialist microsporidian pathogens of mosquitoes

    Science.gov (United States)

    The adaptation of two distantly related microsporidia to their mosquito hosts was investigated. Edhazardia aedis is a specialist pathogen that infects Aedes aegypti, the main vector of dengue and yellow fever arboviruses. Vavraia culicis is a generalist pathogen of several insects including Anophele...

  18. Mosquito studies on the Isla de la Juventud, Cuba, at the beginning of rain period.

    Science.gov (United States)

    Ryba, J; Fuentes, O; Danielová, V; Fernández, A

    1984-01-01

    A total of 8418 mosquitoes belonging to 16 species were collected in 11 localities of the Isla de la Juventud. The most abundant species was Aedes taeniorhynchus (92% of specimens collected). The species Wyeomyia vanduzeei and Mansonia nigricans were encountered on the island for the first time. PMID:6146558

  19. Efficacy of extracts of Bacillus thuringiensis israelensis for the control of mosquito vectors.

    Science.gov (United States)

    More than 1 million human cases of Chikungunya were recently reported in India. Aedes aegypti (the yellow fever mosquito) is an important disease vector in India where it transmits Chikungunya, dengue, and yellow fever viruses to humans. In this study, scientists from Bharathiar University in Coim...

  20. Larvicidal potential of commercially available pine (Pinus longifolia) and cinnamon ( Cinnamnomum zeylanicum) oils against dengue fever mosquito, Aedes aegypti L.( Diptera: Culicidae)%市售长叶松油和锡兰肉桂油对登革热媒蚊埃及伊蚊的灭幼效果

    Institute of Scientific and Technical Information of China (English)

    Radhika WARIKOO; Naim WAHAB; Sarita KUMAR

    2011-01-01

    The aromatic nature of pine and cinnamon oils has established them as good adult repellents but their larvicidal efficacy against mosquitoes has not been explored much.Keeping this in view,laboratory studies were conducted to uncover the larvicidal potential of commercially available pine ( Pinus longifolia) oil and cinnamon ( Cinnamomum zeylanicum) oil against the early 4th instar larvae of Aedes aegypti, originating from Delhi, India.The larvicidal effects were investigated in terms of the larval mortality, behavioural and morphological changes, if any.Our studies revealed the larvicidal efficiency of both the oils against 4th instar larvae of Ae.aegypti, the pine oil proving to be more effective than the cinnamon oil.The LC50 and LC70values exhibited by pine oil were 0.33093 mg/L and 0.54476 mg/L,respectively, while the values obtained with cinnamon oil were 0.63159 mg/L and 0.77736 mg/L,respectively.It was further observed that at LC90 the larvicidal potential of cinnamon oil surpassed that of the pine oil, exhibiting a value of 1.11879 mg/L as in comparison to 1.04915 mg/L shown by pine oil.The behavioural changes as excitation, restlessness, tremors, and convulsions followed by paralysis observed in the treated larvae suggest a probable effect of the oils on their neuromuscular system.Microscopic study of morphological alterations in the treated larvae revealed that most of their organs had a normal structural appearance as that of controls except the little internal shrinkage in anal gills leading to the structural deformity.This indicates the anal gills as the probable action sites of the oil extracts and dysfunction of the gills leading to larval mortality.The potential of oils as new types of larvicides for the control of mosquitoes are explored.%松油和桂皮油由于具有芳香性气味,因而成为良好的成虫驱避剂,但是关于它们对蚊虫的杀幼虫作用研究不多.为揭示市售的长叶松Pinus longifolia

  1. Prevalence of Ascogregarina spp. in the container breeding Aedes albopictus from Chikungunya fever affected areas of Kerala State, India.

    Science.gov (United States)

    Muniaraj, M; Rajendran, R; Arunachalam, N; Paramasivan, R; Samuel, P Philip

    2010-06-01

    The prevalence of protozoan, Ascogregarina sp. had been determined in the container breeding mosquitoes, Aedes albopictus. Since, the cyst of Ascogregarina might play role in the maintenance of the Chik virus during silent period, the presence of Ascogregarina has gained importance in recent days. The prevalence was found to be 71.62. PMID:22471176

  2. 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

  3. Encontro de Aedes (Stegomyia albopictus (Skuse em Bromeliaceae na periferia de São Paulo, SP, Brasil

    Directory of Open Access Journals (Sweden)

    Natal Delsio

    1997-01-01

    Full Text Available Foram coletadas larvas de Aedes albopictus em uma planta da família Bromeliaceae, na periferia da cidade de São Paulo, SP, Brasil. Esse encontro abre perspectivas de estudo para avaliação do potencial desse vegetal como criadouro desse mosquito no País.

  4. Chapter 3. Integration of botanicals and microbial pesticides for the control of dengue vector, Aedes aegypti (Insecta: Diptera: Culicidae)

    Science.gov (United States)

    Mosquitoes are the single most important group of insects in terms of public health significance and causing diseases such as malaria, filariasis, dengue fever, Japanese encephalitis and other fevers. There has been an outbreak of Chikungunya and dengue all over the India from 2006 – 2009. Aedes ae...

  5. Global stability of a delayed mosquito-transmitted disease model with stage structure

    Directory of Open Access Journals (Sweden)

    B. G. Sampath Aruna Pradeep

    2015-01-01

    Full Text Available This article presents a new eco-epidemiological deterministic delay differential equation model considering a biological controlling approach on mosquitoes, for endemic dengue disease with variable host (human and variable vector (Aedes aegypti populations, and stage structure for mosquitoes. In this model, predator-prey interaction is considered by using larvae as prey and mosquito-fish as predator. We give a complete classification of equilibria of the model, and sufficient conditions for global stability/global attractivity of some equilibria are given by constructing suitable Lyapunov functionals and using Lyapunov-LaSalle invariance principle. Also, numerical simulations are presented to show the validity of our results.

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

    Directory of Open Access Journals (Sweden)

    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

  7. 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

  8. Mosquito Bite Prevention For Travelers

    Science.gov (United States)

    Mosquito Bite Prevention for Travelers Mosquitoes spread many types of viruses and parasites that can cause diseases ... be available. Protect yourself and your family from mosquito bites. Here’s how: Keep mosquitoes out of your ...

  9. Effects of combination of leaf resources on competition in container mosquito larvae.

    Science.gov (United States)

    Reiskind, M H; Zarrabi, A A; Lounibos, L P

    2012-08-01

    Resource diversity is critical to fitness in many insect species, and may determine the coexistence of competitive species and the function of ecosystems. Plant material provides the nutritional base for numerous aquatic systems, yet the consequences of diversity of plant material have not been studied in aquatic container systems important for the production of mosquitoes. To address how diversity in leaf detritus affects container-inhabiting mosquitoes, we examined how leaf species affect competition between two container inhabiting mosquito larvae, Aedes aegypti and Aedes albopictus, that co-occur in many parts of the world. We tested the hypotheses that leaf species changes the outcome of intra- and interspecific competition between these mosquito species, and that combinations of leaf species affect competition in a manner not predictable based upon the response to each leaf species alone (i.e. the response to leaf combinations is non-additive). We find support for our first hypothesis that leaf species can affect competition, evidence that, in general, leaf combination alters competitive interactions, and no support that leaf combination impacts interspecific competition differently than intraspecific competition. We conclude that combinations of leaves increase mosquito production non-additively such that combinations of leaves act synergistically, in general, and result in higher total yield of adult mosquitoes in most cases, although certain leaf combinations for A. albopictus are antagonistic. We also conclude that leaf diversity does not have a different effect on interspecific competition between A. aegypti and A. albopictus, relative to intraspecific competition for each mosquito. PMID:22314102

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

    Directory of Open Access Journals (Sweden)

    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.

  11. 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

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

    International Nuclear Information System (INIS)

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2014-01-15

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

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

    Directory of Open Access Journals (Sweden)

    M. Deepa

    2014-12-01

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

  15. Attractiveness test of attractants toward dengue virus vector (Aedes aegypti into lethal mosquiTrap modifications (LMM

    Directory of Open Access Journals (Sweden)

    Munawir Sazali

    2014-12-01

    Full Text Available Laboratory tests have been conducted to determine the ability of Lethal MosquiTRAP Modification (LMM. Modification is basically done to maximize the capture ability toward Aedes aegypti mosquitoes with the addition of black color, sticky material and attractants. Disposable plastic bottles were transformed to Lethal mosquiTRAP modification with the addition of attractant sources obtained from hay (Oriza sativa and red chili (Capsicum annum infusion and palm sugar (Arenga pinnata fermentation. Aedes mosquitoes attracted towards different attractant sources are simultaneously killed directly in the trap. Response analysis of Aedes aegypti mosquitoes using different attractant sources was done. There is no significant difference (p=0.984 between different type of attractants, but, the attractant concentrations (10%, 30% and 60% showed a significant difference (p=0.00<0.05 against number of mosquitoes caught in the trap. Statistical average of mosquitoes trapped showed that concentration of 30% was the best combination in the mosquiTRAP. Thus, expected from laboratory tests such mosquiTRAP can be installed in the environment as a dengue vector control measure.

  16. UV light and urban pollution: bad cocktail for mosquitoes?

    Science.gov (United States)

    Tetreau, Guillaume; Chandor-Proust, Alexia; Faucon, Frédéric; Stalinski, Renaud; Akhouayri, Idir; Prud'homme, Sophie M; Régent-Kloeckner, Myriam; Raveton, Muriel; Reynaud, Stéphane

    2014-01-01

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

  17. Surveillance of adult Aedes mosquitoes in response to the outbreak of dengue fever in Xishuangbanna using BG-Sentinel mosquito trap%西双版纳州登革热暴发现场BGS-trap媒介蚊虫监测研究

    Institute of Scientific and Technical Information of China (English)

    刘小波; 郭玉红; 李金海; 王君; 周红宁; 孟凤霞; 陈然; 任东升; 来明月

    2014-01-01

    目的 评价BG-Sentinel mosquito trap (BGS-trap)对登革热媒介成蚊的监测效果,为我国登革热暴发现场伊蚊成蚊监测、风险评估及预测预警提供基础数据.方法 在西双版纳州所辖景洪市、勐腊及勐海县,利用BGS-Trap进行伊蚊成蚊监测,捕获蚊种经形态学鉴定.利用描述流行病学方法对日捕获所有蚊虫进行分析.结果 景洪市5d研究期内,共布放20台BGS-trap,累计捕蚊240 h,捕获蚊虫26只,其中,埃及伊蚊雌性1只,白纹伊蚊8只(雌7只,雄1只),致倦库蚊17只(雌16只,雄1只).勐腊、勐海县各放置BGS-trap 3台,捕蚊时间各108 h,均未捕到埃及伊蚊及白纹伊蚊.勐腊县捕获三带喙库蚊2只(雌雄各1只),勐海县捕获致倦库蚊2只(雌雄各1只).结论 BGS-trap在此次云南省西双版纳州登革热暴发现场伊蚊成蚊监测中效果不理想,需在现场和实验室对该装置进行进一步媒介伊蚊成蚊监测效果评价工作.

  18. Peculiar liquid-feeding and pathogen transmission behavior of Aedes togoi and comparison with Anopheles sinensis

    Science.gov (United States)

    Lee, Sang Joon; Kang, Dooho; Lee, Seung Chul; Ha, Young-Ran

    2016-02-01

    Female mosquitoes transmit various diseases as vectors during liquid-feeding. Identifying the determinants of vector efficiency is a major scientific challenge in establishing strategies against these diseases. Infection rate and transmission efficiency are interconnected with the mosquito-induced liquid-feeding flow as main indexes of vector efficiency. However, the relationship between liquid-feeding characteristics and pathogen remains poorly understood. The liquid-feeding behavior of Aedes togoi and Anopheles sinensis was comparatively investigated in conjunction with vector efficiency via micro-particle image velocimetry. The flow rates and ratio of the ejection volume of Aedes togoi were markedly higher than those of Anophels sinensis. These differences would influence pathogen re-ingestion. Wall shear stresses of these mosquito species were also clearly discriminatory affecting the infective rates of vector-borne diseases. The variations in volume of two pump chambers and diameter of proboscis of these mosquito species were compared to determine the differences in the liquid-feeding process. Liquid-feeding characteristics influence vector efficiency; hence, this study can elucidate the vector efficiency of mosquitoes and the vector-pathogen interactions and contribute to the development of strategies against vector-borne diseases.

  19. Play the Mosquito Game

    Science.gov (United States)

    ... Life and Work Teachers' Questionnaire Malaria Play the Mosquito Game Play the Parasite Game About the games ... that is transmitted to humans by a female mosquito's bite. Read More » The Nobel Prize The 1902 ...

  20. Mosquito, adult (image)

    Science.gov (United States)

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

  1. Breeding patterns of Aedes stegomyia albopictus in periurban areas of Calicut, Kerala, India.

    Science.gov (United States)

    Rao, B Bhaskar; George, Biju

    2010-05-01

    Aedes albopictus has been shown to be a vector for diseases which have been on the increase, such as dengue fever and chikungunya infection. We conducted a study of 100 homes from 2006-2009 to determine the breeding sites for Ae. albopictus mosquitoes in Calicut, Kerala, India. We found the larvae of Ae. albopictus mosquitoes most often in coconut shells and plastic waste, followed by tires, flower pots, glass products, egg shells and dumped grinding stones. Ae. albopictus control programs in Calicut, Kerala, India should target these objects as part of a control program. PMID:20578539

  2. 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

  3. Biology and Role of Aedes albopictus (Skuse) 1894 as Vector of Diseases

    OpenAIRE

    Hasan Boesri

    2011-01-01

    Behavior of the mosquito Aedes albopictus is generally res ting outside the home with the brood in a natural or artificial containers protected from sunlight. Human biting activity between the hours of9:00 to 11:00 and between the hours of 17:00 to 18:00 inside and outside the home. The period of rest after sucking the blood 4-5 days and is ready to lie. Habitat or the environment that most coveted of th is mosquito is a forest or gar­den with temperatures of 24-30 0 C. eggs hatch after 4-5 d...

  4. Controlling Mosquitoes Outside

    Centers for Disease Control (CDC) Podcasts

    2016-08-09

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

  5. Encontro de Aedes albopictus no Estado do Pará, Brasil

    Directory of Open Access Journals (Sweden)

    Segura Maria de Nazaré de Oliveira

    2003-01-01

    Full Text Available Pela primeira vez é registrada a presença do Aedes (Stg albopictus no Estado do Pará, Brasil, em área urbana no município de Medicilândia distante cerca de 90 km de Altamira, onde foram capturados por meio de isca humana 42 exemplares de mosquitos adultos. Estes foram inoculados em C6/36 e em camundongos recém-nascidos na tentativa de isolamento viral, não tendo sido isolado nenhum vírus. A presença de Aedes albopictus em áreas da Amazônia onde circulam os vírus de dengue e de febre amarela é preocupante e representa um risco potencial desta espécie de mosquito se tornar infectada com tais vírus.

  6. 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

  7. Modified technique of Wolbachia removal from Malaysian Aedes albopictus

    Institute of Scientific and Technical Information of China (English)

    Sylvia; Joanne; Indra; Vythilingam; Nava; Yugavathy; Jonathan; Inbaraj; Doss

    2014-01-01

    Objective:To develop an artificial and modified Wolbaehia removal technique using tetracycline from naturally Wolbachia infected Aedes albopictus(Ae.albopictus)so as to be able to produce generations of Wolbaehia free offsprings.Methods:In this study,seven different tetracycline treatment methods were conducted to obtain the best removal method.Four methods focused on larvae tetracycline treatment,one method on both larvae and adult tetracycline treatment and the last two methods on adult mosquito sucrose treatment.Results:All larval tetracycline treatments resulted in either high larvae mortality,sterile F_o adult mosquitoes or unsuccessful Wolbaehia removal.Treatment of both larvae and adults resulted in reduced larvae mortality,successful Wolbachia removal but slow mosquito fecundity.As for the adult treatment,1.0 mg/mL as previously published was not aisle to completely remove Wolbaehia in F,generation whereas 1.25 mg/mL successfully removed Wolbachia from F,and F,mosquitoes in 2 weeks.Conclusions:This method is different from the previously published methods as it provides an improved Watbachia removal technique from Ae.albopictus with high egg hatchability.low larvae mortality,increased fecundity and better Wolbaehia removal rate.

  8. Modified technique of Wolbachia removal from Malaysian Aedes albopictus

    Institute of Scientific and Technical Information of China (English)

    Sylvia Joanne; Indra Vythilingam; Nava Yugavathy; Jonathan Inbaraj Doss

    2014-01-01

    Objective: To develop an artificial and modified Wolbachia removal technique using tetracycline from naturally Wolbachia infected Aedes albopictus (Ae. albopictus) so as to be able to produce generations of Wolbachia free offsprings.Methods:In this study, seven different tetracycline treatment methods were conducted to obtain the best removal method. Four methods focused on larvae tetracycline treatment, one method on both larvae and adult tetracycline treatment and the last two methods on adult mosquito sucrose treatment.Results:All larval tetracycline treatments resulted in either high larvae mortality, sterile F0 adult mosquitoes or unsuccessful Wolbachia removal. Treatment of both larvae and adults resulted in reduced larvae mortality, successful Wolbachia removal but slow mosquito fecundity. As for the adult treatment, 1.0 mg/mL as previously published was not able to completely remove Wolbachia in F1 generation whereas 1.25 mg/mL successfully removed Wolbachia from F1 and F2 mosquitoes in 2 weeks. Conclusions: This method is different from the previously published methods as it provides an improved Wolbachia removal technique from Ae. albopictus with high egg hatchability, low larvae mortality, increased fecundity and better Wolbachia removal rate.

  9. Reproductive strategies of Aedes albopictus (Diptera : Culicidae) and implications for the sterile insect technique

    OpenAIRE

    Oliva, Clelia F; David Damiens; Vreysen, Marc J. B.; Guy Lemperière; Jérémie Gilles

    2013-01-01

    Male insects are expected to optimize their reproductive strategy according to the availability of sperm or other ejaculatory materials, and to the availability and reproductive status of females. Here, we investigated the reproductive strategy and sperm management of male and virgin female Aedes albopictus, a mosquito vector of chikungunya and dengue viruses. The dynamics of semen transfer to the female bursa inseminalis and spermathecae were observed. Double-mating experiments were conducte...

  10. 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...

  11. 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...

  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. Aedes albopictus in the United States: ten-year presence and public health implications.

    OpenAIRE

    Moore, C. G.; Mitchell, C J

    1997-01-01

    Since its discovery in Houston, Texas, in 1987, the Asian "tiger mosquito" Aedes albopictus has spread to 678 counties in 25 states. This species, which readily colonizes container habitats in the peridomestic environment, was probably introduced into the continental United States in shipments of scrap tires from northern Asia. The early pattern of dispersal followed the interstate highway system, which suggests further dispersal by human activities. The Public Health Service Act of 1988 requ...

  14. Detection of Wolbachia from field collected Aedes albopictus Skuse in Malaysia

    OpenAIRE

    A Noor Afizah; Roziah, A.; Nazni, W.A.; Lee, H L

    2015-01-01

    Background & objectives: Wolbachia-based vector control strategies have been proposed as a mean to augment the existing measures for controlling dengue vector. Prior to utilizing Wolbachia in novel vector control strategies, it is crucial to understand the Wolbachia-mosquito interactions. Many studies have only focused on the prevalence of Wolbachia in female Aedes albopictus with lack of attention on Wolbachia infection on the male Ae. albopictus which also affects the effective expression o...

  15. 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...

  16. Susceptibility of Aedes albopictus from dengue outbreak areas to temephos and Bacillus thuringiensis subsp. israelensis

    OpenAIRE

    Ahmad Mohiddin; Asmalia Md Lasim; Wan Fatma Zuharah

    2016-01-01

    Objective: To monitor the current duration of the application rates in vector programme and the level of Aedes albopictus larvae susceptibility from three selected areas in northeast district of Penang on two selected larvicides, temephos and Bacillus thuringiensis subsp. israelensis (Bti) which are commonly used by Penang Health Department for vector control. Methods: The mosquito larvae were tested against two types of larvicides: (1) temephos (Abate®) with diagnostic dosage (0.012 mg/L)...

  17. 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...

  18. 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...

  19. 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...

  20. 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...