WorldWideScience

Sample records for aedes aegypti diptera

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

    Science.gov (United States)

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

    2015-07-01

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

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2008-12-01

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

  4. 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

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

    Directory of Open Access Journals (Sweden)

    Almério de Castro Gomes

    2007-04-01

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

  6. Essential oils and their compounds as Aedes aegypti L. (Diptera: Culicidae) larvicides: review.

    Science.gov (United States)

    Dias, Clarice Noleto; Moraes, Denise Fernandes Coutinho

    2014-02-01

    This review aims to describe essential oils and their constituent compounds that exhibit bioactivity against Aedes aegypti L. (Diptera: Culicidae) larvae, the immature stage of the primary vector of dengue. This review is based on original articles obtained by searching on major databases. Our literature review revealed that 361 essential oils from 269 plant species have been tested for their larvicidal activity. More than 60 % of these essential oils were considered active (LC50temephos in container breeding. Approximately 27 % of the plants studied for their larvicidal activity against A. aegypti were collected in Brazil. Essential oils rich in phenylpropanoids, oxygenated sesquiterpenes, and monoterpene hydrocarbons were found to be the most active. When the isolates were tested, phenylpropanoids and monoterpene hydrocarbons were the most active compound classes. We describe the plant parts used and the major constituents of the essential oils. In addition, we discuss factors affecting the activity (such as plant parts, age of the plant, chemotypes, larval source, and methods used), structure-activity relationships, and mechanisms of action of the essential oils and their compounds. Essential oils have been widely investigated and show high larvicidal activity against A. aegypti. This review reveals that the essential oils are effective alternatives for the production of larvicides, which can be used in vector-borne disease control programmes. PMID:24265058

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

    Science.gov (United States)

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

    2014-11-01

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

  8. Insecticide resistance in two Aedes aegypti (Diptera: Culicidae) strains from Costa Rica.

    Science.gov (United States)

    Bisset, J A; Marín, R; Rodríguez, M M; Severson, D W; Ricardo, Y; French, L; Díaz, M; Pérez, O

    2013-03-01

    Dengue (family Flaviridae, genus Flavivirus, DENV) and dengue hemorrhagic fever (DHF) are presently important public health problems in Costa Rica. The primary strategy for disease control is based on reducing population densities of the main mosquito vector Aedes aegypti (L.) (Diptera: Culicidae). This is heavily dependent on use of chemical insecticides, thus the development of resistance is a frequent threat to control program effectiveness. The objective of this study was to determine the levels of insecticide resistance and the metabolic resistance mechanisms involved in two Ae. aegypti strains collected from two provinces (Puntarenas and Limon) in Costa Rica. Bioassays with larvae were performed according to World Health Organization guidelines and resistance in adults was measured through standard bottle assays. The activities of beta-esterases, cytochrome P450 monooxygenases, and glutathione S-transferases (GST), were assayed through synergists and biochemical tests, wherein the threshold criteria for each enzyme was established using the susceptible Rockefeller strain. The results showed higher resistance levels to the organophosphate (OP) temephos and the pyrethroid deltamethrin in larvae. The efficacy of commercial formulations of temephos in controlling Ae. aegypti populations was 100% mortality up to 11 and 12 d posttreatment with daily water replacements in test containers. Temephos and deltamethrin resistance in larvae were associated with high esterase activity, but not to cytochrome P450 monooxygenase or GST activities. Adult mosquitoes were resistant to deltamethrin, and susceptible to bendiocarb, chlorpyrifos, and cypermethrin. Because temephos and deltamethrin resistance are emerging at the studied sites, alternative insecticides should be considered. The insecticides chlorpyrifos and cypermethrin could be good candidates to use as alternatives for Ae. aegypti control. PMID:23540124

  9. Derris (Lonchocarpus urucu (Leguminosae Extract Modifies the Peritrophic Matrix Structure of Aedes aegypti (Diptera:Culicidae

    Directory of Open Access Journals (Sweden)

    Gusmão Desiely Silva

    2002-01-01

    Full Text Available Aqueous suspension of ethanol extracts of Derris (Lonchocarpus urucu (Leguminosae, collected in the state of Amazonas, Brazil, were tested for larvicidal activity against the mosquito Aedes aegypti (Diptera:Culicidae. The aim of this study was to observe the alterations of peritrophic matrix in Ae. aegypti larvae treated with an aqueous suspension of D. urucu extract. Different concentrations of D. urucu root extract were tested against fourth instar larvae. One hundred percent mortality was observed at 150 µg/ml (LC50 17.6 µg/ml 24 h following treatment. In response to D. urucu feeding, larvae excreted a large amount of amorphous feces, while control larvae did not produce feces during the assay period. Ultrastructural studies showed that larvae fed with 150 µg/ml of D. urucu extract for 4 h have an imperfect peritrophic matrix and extensive damage of the midgut epithelium. Data indicate a protective role for the peritrophic matrix. The structural modification of the peritrophic matrix is intrinsically associated with larval mortality.

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

    Science.gov (United States)

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

    2008-05-01

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

  11. Larvicidal efficacy of different plant parts of railway creeper, Ipomoea cairica Extract Against Dengue Vector Mosquitoes, Aedes albopictus (Diptera: Culicidae) and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    AhbiRami, Rattanam; Zuharah, Wan Fatma; Thiagaletchumi, Maniam; Subramaniam, Sreeramanan; Sundarasekar, Jeevandran

    2014-01-01

    Natural insecticides from plant origin against mosquito vectors have been the main concern for research due to their high level of eco-safety. Control of mosquitoes in their larval stages are an ideal method since Aedes larvae are aquatic, thus it is easier to deal with them in this habitat. The present study was specifically conducted to explore the larvicidal efficacy of different plant parts of Ipomoea cairica (L.) or railway creeper crude extract obtained using two different solvents; methanol and acetone against late third-stage larvae of Aedes albopictus (Skuse) and Aedes aegypti (L.) (Diptera: Culicidae). Plant materials of I. cairica leaf, flower, and stem were segregated, airdried, powdered, and extracted using Soxhlet apparatus. Larvicidal bioassays were performed by using World Health Organization standard larval susceptibility test method for each species which were conducted separately for different concentration ranging from 10 to 450 ppm. Both acetone and methanol extracts showed 100% mortality at highest concentration tested (450 ppm) after 24 h of exposure. Results from factorial ANOVA indicated that there were significant differences in larvicidal effects between mosquito species, solvent used and plant parts (F=5.71, df=2, Paegypti with LC50 of 101.94 ppm followed by Ae. albopictus with LC50 of 105.59 ppm compared with other fractions of I. cairica extract obtained from flower, stem, and when methanol are used as solvent. The larvae of Ae. aegypti appeared to be more susceptible to I. cairica extract with lower LC50 value compared with Ae. albopictus (F=8.83, df=1, Pinsecticide for the control of Aedes mosquitoes. This study quantified the larvicidal property of I. cairica extract, providing information on lethal concentration that may have potential for a more eco-friendly Aedes mosquito control program.

  12. 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...

  13. Larvicidal and repellent activity of tetradecanoic acid againstAedes aegypti (Linn.) andCulex quinquefasciatus (Say.) (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Sivakumar R; Jebanesan A; Govindarajan M; Rajasekar P

    2011-01-01

    Objective:To investigate the larvicidal and repellent efficacy of tetradecanoic acid against Aedes aegypti (Ae. aegypti) L. andCulex quinquefasciatus (Cx. quinquefasciatus) Say (Diptera: Culicidae).Methods: Larvicidal efficacy of tetradecanoic acid was tested at various concentrations against the early third instar larvae of Ae. aegypti andCx. quinquefasciatus. The repellent activity was determined against two mosquito species at three concentrations viz.,1.0,2.5 and5.0 ppm under the laboratory conditions.Results: The tetradecanoic acid was found to be more effective againstCx. quinquefasciatus thanAe. aegypti larvae. TheLC50values were14.08 ppm and25.10 ppm, respectively. Tetradecanoic acid showed lesser repellency againstAe. aegypti andCx. quinquefasciatus. The highest repellency was observed in higher concentration of5.0 mg/cm2provided100% protection up to60 and 90 min againstAe. aegypti andCx. quinquefasciatusrespectively.Conclusions: From the results it can be concluded the tetradecanoic acid is a potential for controlling Cx. quinquefasciatus andAe. aegypti mosquitoes.

  14. The Efficacy of Some Commercially Available Insect Repellents for Aedes aegypti (Diptera: Culicidae) and Aedes albopictus (Diptera: Culicidae).

    Science.gov (United States)

    Rodriguez, Stacy D; Drake, Lisa L; Price, David P; Hammond, John I; Hansen, Immo A

    2015-01-01

    Reducing the number of host-vector interactions is an effective way to reduce the spread of vector-borne diseases. Repellents are widely used to protect humans from a variety of protozoans, viruses, and nematodes. DEET (N,N-Diethyl-meta-toluamide), a safe and effective repellent, was developed during World War II. Fear of possible side effects of DEET has created a large market for "natural" DEET-free repellents with a variety of active ingredients. We present a comparative study on the efficacy of eight commercially available products, two fragrances, and a vitamin B patch. The products were tested using a human hand as attractant in a Y-tube olfactometer setup with Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse), both major human disease vectors. We found that Ae. albopictus were generally less attracted to the test subject's hand compared with Ae, aegypti. Repellents with DEET as active ingredient had a prominent repellency effect over longer times and on both species. Repellents containing p-menthane-3,8-diol produced comparable results but for shorter time periods. Some of the DEET-free products containing citronella or geraniol did not have any significant repellency effect. Interestingly, the perfume we tested had a modest repellency effect early after application, and the vitamin B patch had no effect on either species. This study shows that the different active ingredients in commercially available mosquito repellent products are not equivalent in terms of duration and strength of repellency. Our results suggest that products containing DEET or p-menthane-3,8-diol have long-lasting repellent effects and therefore provide good protection from mosquito-borne diseases. PMID:26443777

  15. 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. 

  16. 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...

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

    OpenAIRE

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

    2014-01-01

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

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

    OpenAIRE

    Rodríguez Coto, María Magdalena

    2008-01-01

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

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

    Energy Technology Data Exchange (ETDEWEB)

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

    2007-09-15

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

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

    International Nuclear Information System (INIS)

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

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

    Science.gov (United States)

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

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

    Directory of Open Access Journals (Sweden)

    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.

  3. Susceptibility of larvae of Aedes aegypti (Linnaeus (Diptera: Culicidae to entomopathogenic nematode Heterorhabditis bacteriophora (Poinar (Rhabditida: Heterorhabditidae

    Directory of Open Access Journals (Sweden)

    María L. PESCHIUTTA

    2014-01-01

    Full Text Available Aedes aegypti (Linnaeus (Diptera: Culicidae es vector de los agentes etiológicos de la fiebre amarilla y del dengue. Una alternativa al control químico de este vector es el uso de agentes biológicos. Los nematodos entomopatógenos son efectivos en el control de plagas. La infectividad y el ciclo de vida de un aislado argentino de Heterorhabditis bacteriophora Poinar (Rhabditida: Heterorhabditidae en larvas de A. aegypti se registró por primera vez bajo condiciones de laborato - rio. Para cada unidad experimental, 30 larvas de mosquito de segundo estadio fueron expuestas a 8 dosis del nematodo (0:1, 1:1, 5:1, 15:1, 100:1, 500:1, 750:1, 1500:1. Los juveniles infectivos (JIs utilizados fueron multiplicados sobre Galleria mellonella (Lepidoptera: Pyralidae. La continuidad infectiva de los JIs obtenidos de A. aegypti fue probada aplicándolos en una dosis de 100:1 sobre larvas del mosquito . Las tasas de mortalidad fueron de 0% a 84%. El número de nematodos desarrollados dentro de la larva de mosquito, la mortalidad larval y los nuevos JIs se incrementaron con el aumento de la dosis de nematodos. Los resultados indican que H. bacteriophora es capaz de infectar larvas de A. aegypti , se desarrolla y produce nuevos JIs, permitiendo la continuidad de su ciclo de vida.

  4. Chemical Composition and Larvicidal Activity of Essential Oils Extracted from Brazilian Legal Amazon Plants against Aedes aegypti L. (Diptera: Culicidae)

    Science.gov (United States)

    Dias, Clarice Noleto; Alves, Luciana Patrícia Lima; Rodrigues, Klinger Antonio da Franca; Brito, Maria Cristiane Aranha; Rosa, Carliane dos Santos; do Amaral, Flavia Maria Mendonça; Monteiro, Odair dos Santos; Andrade, Eloisa Helena de Aguiar; Maia, José Guilherme Soares; Moraes, Denise Fernandes Coutinho

    2015-01-01

    The mosquito Aedes aegypti L. (Diptera: Culicidae) is the major vector of dengue and chikungunya fever. The lack of effective therapies and vaccines for these diseases highlights the need for alternative strategies to control the spread of virus. Therefore, this study investigated the larvicidal potential of essential oils from common plant species obtained from the Chapada das Mesas National Park, Brazil, against third instar A. aegypti larvae. The chemical composition of these oils was determined by gas chromatography coupled to mass spectrometry. The essential oils of Eugenia piauhiensis Vellaff., Myrcia erythroxylon O. Berg, Psidium myrsinites DC., and Siparuna camporum (Tul.) A. DC. were observed to be mainly composed of sesquiterpene hydrocarbons. The essential oil of Lippia gracilis Schauer was composed of oxygenated monoterpenes. Four of the five tested oils were effective against the A. aegypti larvae, with the lethal concentration (LC50) ranging from 230 to 292 mg/L after 24 h of exposure. Overall, this work demonstrated the possibility of developing larvicidal products against A. aegypti by using essential oils from the flora of the Brazilian Legal Amazon. This in turn demonstrates the potential of using natural resources for the control of disease vectors. PMID:25949264

  5. Chemical Composition and Larvicidal Activity of Essential Oils Extracted from Brazilian Legal Amazon Plants against Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Dias, Clarice Noleto; Alves, Luciana Patrícia Lima; Rodrigues, Klinger Antonio da Franca; Brito, Maria Cristiane Aranha; Rosa, Carliane Dos Santos; do Amaral, Flavia Maria Mendonça; Monteiro, Odair Dos Santos; Andrade, Eloisa Helena de Aguiar; Maia, José Guilherme Soares; Moraes, Denise Fernandes Coutinho

    2015-01-01

    The mosquito Aedes aegypti L. (Diptera: Culicidae) is the major vector of dengue and chikungunya fever. The lack of effective therapies and vaccines for these diseases highlights the need for alternative strategies to control the spread of virus. Therefore, this study investigated the larvicidal potential of essential oils from common plant species obtained from the Chapada das Mesas National Park, Brazil, against third instar A. aegypti larvae. The chemical composition of these oils was determined by gas chromatography coupled to mass spectrometry. The essential oils of Eugenia piauhiensis Vellaff., Myrcia erythroxylon O. Berg, Psidium myrsinites DC., and Siparuna camporum (Tul.) A. DC. were observed to be mainly composed of sesquiterpene hydrocarbons. The essential oil of Lippia gracilis Schauer was composed of oxygenated monoterpenes. Four of the five tested oils were effective against the A. aegypti larvae, with the lethal concentration (LC50) ranging from 230 to 292 mg/L after 24 h of exposure. Overall, this work demonstrated the possibility of developing larvicidal products against A. aegypti by using essential oils from the flora of the Brazilian Legal Amazon. This in turn demonstrates the potential of using natural resources for the control of disease vectors. PMID:25949264

  6. Chemical Composition and Larvicidal Activity of Essential Oils Extracted from Brazilian Legal Amazon Plants against Aedes aegypti L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Clarice Noleto Dias

    2015-01-01

    Full Text Available The mosquito Aedes aegypti L. (Diptera: Culicidae is the major vector of dengue and chikungunya fever. The lack of effective therapies and vaccines for these diseases highlights the need for alternative strategies to control the spread of virus. Therefore, this study investigated the larvicidal potential of essential oils from common plant species obtained from the Chapada das Mesas National Park, Brazil, against third instar A. aegypti larvae. The chemical composition of these oils was determined by gas chromatography coupled to mass spectrometry. The essential oils of Eugenia piauhiensis Vellaff., Myrcia erythroxylon O. Berg, Psidium myrsinites DC., and Siparuna camporum (Tul. A. DC. were observed to be mainly composed of sesquiterpene hydrocarbons. The essential oil of Lippia gracilis Schauer was composed of oxygenated monoterpenes. Four of the five tested oils were effective against the A. aegypti larvae, with the lethal concentration (LC50 ranging from 230 to 292 mg/L after 24 h of exposure. Overall, this work demonstrated the possibility of developing larvicidal products against A. aegypti by using essential oils from the flora of the Brazilian Legal Amazon. This in turn demonstrates the potential of using natural resources for the control of disease vectors.

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

    Science.gov (United States)

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

    2008-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Jeymesson Raphael Cardoso Vieira

    2012-01-01

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

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

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

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

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

    Science.gov (United States)

    Johnson, Brian J; Ritchie, Scott A

    2016-01-01

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

  11. 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...

  12. 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

  13. Larvicidal activity of some Euphorbiaceae plant extracts against Aedes aegypti and Culex quinquefasciatus (Diptera: Culicidae).

    Science.gov (United States)

    Rahuman, A Abdul; Gopalakrishnan, Geetha; Venkatesan, P; Geetha, Kannappan

    2008-04-01

    Larvicidal activity of ethyl acetate, butanol, and petroleum ether extracts of five species of Euphorbiaceae plants, Jatropha curcas, Pedilanthus tithymaloides, Phyllanthus amarus, Euphorbia hirta, and Euphorbia tirucalli, were tested against the early fourth instar larvae of Aedes aegypti L. and Culex quinquefasciatus (Say). The larval mortality was observed after 24 h of exposure. All extracts showed low larvicidal effects; however, the highest larval mortality was found in petroleum ether extract. The LC50 value of petroleum ether extracts of J. curcas, P. tithymaloides, P. amarus, E. hirta, and E. tirucalli were 8.79, 55.26, 90.92, 272.36, and 4.25 ppm, respectively, against A. aegypti and 11.34, 76.61, 113.40, 424.94, and 5.52 ppm, respectively, against C quinquefasciatus. Of the various ratios tested, the petroleum ether extracts of J. curcas and E. tirucalli were observed to be more efficient than the other plant extracts. It is, therefore, suggested that E. tirucalli can be applied as an ideal potential larvicide against A. aegypti and C. quinquefasciatus. This is an ideal ecofriendly approach for the control of the dengue vector, A. aegypti, and the lymphatic filariasis vector, C. quinquefasciatus.

  14. Toxicity of Mexican native plant extracts against larvae of Aedes aegypti(Diptera: Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Rosario; Ruiz-Guerrero; Mario; Alberto; Rodríguez-Pérez; Mariano; Norzagaray-Campos

    2015-01-01

    Objective: To evaluate five indigenous Mexican plants [Hippocratea excelsa, Hippocratea celastroides, Argemone mexicana(A. mexicana), Tagetes lucida, and Pseudosmodingium perniciosum(P. perniciosum)] toxicity against the fourth instar larvae of the dengue primary vector, Aedes aegypti(A. aegypti).Methods: Each plant part was treated successively with hexane, ethyl acetate, acetone, and methanol to extract potential active components of the plants against the dengue vector.Results: There was a range of toxicity at 24 or 48 h post-exposure for the different plant parts and organic solvent used(LC50 values ranged between 20 and 890 μg/mL). Extracts from seeds of A. mexicana(hexane washing with methanol and acetone) and stem-bark of P. perniciosum(hexane) showed highest toxicity to Ae. aegypti larvae at 48 h post-exposure(LC50 values were80, 50, and 20 μg/mL, respectively), thus making them potential candidates as biolarvicides.Efforts are on-going to characterize the bioactive components of the extracts, through chromatography, for their use as biological tools for the control of the primary dengue vector.Conclusions: A. mexicana and P. perniciosum are good candidates to combat the dengue vector, Ae. aegypti, as they were highly toxic to the larvae.

  15. Genetics and morphology of Aedes aegypti (Diptera: Culicidae) in septic tanks in Puerto Rico.

    Science.gov (United States)

    Somers, Gerard; Brown, Julia E; Barrera, Roberto; Powell, Jeffrey R

    2011-11-01

    Dengue viruses, primarily transmitted by the mosquito Aedes aegypti (L.), affect an estimated 50-100 million people yearly. Traditional approaches to control mosquito population numbers, such as the use of pesticides, have had only limited success. Atypical mosquito behavior may be one reason why current vector control efforts have been less efficacious than expected. In Puerto Rico, for example, adult Ae. aegypti have been observed emerging from septic tanks. Interestingly, adults emerging from septic tanks are larger on average than adults collected from surface containers. To determine whether adults colonizing septic tanks constitute a separate Ae. aegypti population, we used 12 previously validated microsatellite loci to examine adult mosquitoes collected from both septic tanks and surface containers, but found no evidence to suggest genetic differentiation. Size differences between septic tank and surface mosquitoes were reduced when nutrient levels were held constant across experimental groups. Despite the absence of evidence suggesting a genetic difference between experimental groups in this study, Ae. aegypti emerging from septic tanks may still represent a more dangerous phenotype and should be given special consideration when developing vector control programs and designing public health interventions in the future.

  16. Repellence of essential oils of aromatic plants growing in Argentina against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Gleiser, Raquel M; Bonino, Maria A; Zygadlo, Julio A

    2011-01-01

    Mosquitoes are vectors of pathogens to humans and domestic animals and may also have economical impacts. One approach to prevent mosquito-borne diseases is bite deterrence through the application of repellents. Currently, there is an interest to search for alternative bioactive products to the synthetic active ingredients most widely used in insect repellents. Repellence against Aedes aegypti of essential oils extracted from Acantholippia salsoloides, Aloysia catamarcensis, Aloysia polystachya, Lippia integrifolia, Lippia junelliana (Verbenaceae), Baccharis salicifolia, Euphatorium buniifolium, and Tagetes filifolia (Asteraceae) were assessed. Tests were conducted by alternatively exposing untreated and treated forehand to the mosquitoes and counting probing attempts. All essential oils tested were significantly repellent against A. aegypti when compared to untreated controls; L. junelliana was the most repellent and T. filifolia was the least based on the response of the mosquitoes to different concentrations of the essential oils (EO). Repellence may be attributed to the respective main components of each EO. PMID:20838809

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

    Directory of Open Access Journals (Sweden)

    Jairo Campos

    2003-04-01

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

  18. Biosynthesis of silver nanoparticles using Bacillus thuringiensis against dengue vector, Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Banu, A Najitha; Balasubramanian, C; Moorthi, P Vinayaga

    2014-01-01

    The present study reveals the larvicidal activity of silver nanoparticles (AgNPs) synthesized by Bacillus thuringiensis (Bt) against Aedes aegypti responsible for the diseases of public health importance. The Bt-AgNPs were characterized by using UV-visible spectrophotometer followed by scanning electron microscopy (SEM) and energy-dispersive X-ray (EDX) spectroscopy. A surface plasmon resonance spectrum of AgNps was obtained at 420 nm. The particle sizes were measured through SEM imaging ranging from 43.52 to 142.97 nm. The Bt-AgNPs has also given a characteristic peak at 3 keV in EDX image. Interestingly, the mortality rendered by Bt-AgNPs was comparatively high than that of the control against third-instar larvae of A. aegypti (LC50 0.10 ppm and LC90 0.39 ppm) in all the tested concentrations, viz. 0.03, 0.06, 0.09, 0.12, and 0.15 ppm. Hence, Bt-AgNPs would be significantly used as a potent mosquito larvicide against A. aegypti.

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

    Directory of Open Access Journals (Sweden)

    Tahany Hassan Ayaad

    2015-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Younoussa Lame

    2014-12-01

    Full Text Available The purpose of the present study was to evaluate the larvicidal activity of leaf fractions of Annona senegalensis and Boswellia dalzielii against fourth instar larvae of Aedes aegypti. Fourth instar larvae of Ae. aegypti were exposed for 24 hours to various concentrations (312.5-2500 mg/L of methanolic crude extract and its fractions obtained with n-hexane, chloroform, ethyl-acetate and methanol solvents, following WHO method. The mortalities recorded were subjected to ANOVA test for mean comparison and Probit analysis to determine LC50. Preliminary phytochemical screening test for some components of the plants assessed were also evaluated. The phytochemical screening of the two plants revealed the presence of alkaloids, steroids, phenolic compounds, terpenoids, fats and oils in the crude extracts which, after splitting were most distributed in n-hexane and chloroform fractions. Apart from methanol fraction, all products used showed a significant (P<0.001 concentration-dependent toxicity against Ae. aegypti larvae. The LC50 recorded with crude extract were 759.6 and 830.4 mg/L for A. senegalensis and B. dalzielli respectively. After fractionation, n-hexane and chloroform fractions of A. senegalensis revealed more effective activity than others with CL50 values of 379.3 and 595.2 mg/L respectively. As for B. dalzielli, n-hexane (LC50=537.1 mg/L and chloroform (LC50=585.5 mg/L fractions were also the most effective. These results suggest that the n-hexane and chloroform fractions of these plants as a promising larvicide against Ae. aegypti and can constitute the best basic and vital step in the development of a botanical insecticide source.

  1. Effect of phenobarbital on inducing insecticide tolerance and esterase changes in Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Rita de Cássia Sousa-Polezzi

    2004-01-01

    Full Text Available The effect of phenobarbital (PB on the induction of tolerance to the organophosphorous insecticide temephos (TE was investigated in Aedes aegypti L4 larvae submitted to two different PB-treatments:(1 continuous treatment from the egg to the larval L4 stage and (2 discontinuous treatment in which L4 larvae were exposed for 30 h. Mosquitoes from two Brazilian cities were studied: São José do Rio Preto (SJ in São Paulo State and Goiânia (GO in Goiás State. According to criterions established by World Health Organization (WHO mosquitoes from SJ are organophosphate-susceptible while mosquitoes from GO are organophosphate-resistant. For both SJ and GO larvae the two different PB-treatments resulted in significantly increased tolerance (measured by reduced mortality to 0.01mg/L TE while for larvae exposed to 0.02 mg/L TE only continuous PB-treatment resulted in significantly increased TE-tolerance. The reduction of mortality rate was greater in SJ larvae than in GO larvae, confirming data from other organisms indicating that the effect of PB is more pronounced in susceptible strains. To test if oxidase enzymes were involved in PB-induced tolerance we treated PB-pretreated SJ and GO larvae with the oxidase inhibitor piperonyl butoxide (PBO before exposure to TE and observed increased (rather than decreased tolerance, suggesting that oxidases are not involved in the tolerance process and that PB and PBO can act in concert or synergistically. Esterase patterns of PB-pretreated larvae indicated that the cholinesterases EST-13 and EST-14 are involved in the PB-induced TE- tolerance, reinforcing a previous study carried out in our laboratory which suggested that increased esterase synthesis is the mechanism responsible for the development of insecticide resistance in Aedes aegypti.

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

    OpenAIRE

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2009-01-01

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

  4. Bioactivity of plant extracts on the larval and pupal stages of Aedes aegypti (Diptera, Culicidea

    Directory of Open Access Journals (Sweden)

    Lafayette Pereira Candido

    2013-07-01

    Full Text Available Introduction Aedes aegypti is responsible for the transmission of the dengue and yellow fever viruses. This study evaluated the effects of extracts from Cnidosculos phyllacanthus, Ricinus communis, and Coutarea hexandra on the developmental periods of A.aegypti larvae and pupae. Crude extracts of C. phyllacanthus and C. hexandra and oil from R. communis and C. phyllacanthus were used. Methods Bioassays of the larvicidal and pupicidal effects of these products at different concentrations and times of exposure were evaluated. The lethal and sublethal effects were determined using different concentrations in larvicidal tests. Mortality data were evaluated by Probit analysis to determine the LC50 and LC90 values. Results The vegetable oils from C. phyllacanthus and R. communis demonstrated greater efficiency for larval control with an LC50=0.28µl/mL and an LC90=1.48µl/mL and LC50=0.029µl/mL and a LC90=0.26µl/mL, respectively. In pupal tests toxic effects for all insects were verified after exposure to the products at significant LC50 and LC90 values for 24 and 48h. The effects of sublethal concentrations of C. phyllacanthus (oil were more effective on the insects. Conclusions The vegetables oils from C. phyllacanthus and R. communis demonstrated greater potential from the control of different developmental periods in the life cycle of this insect.

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

    Science.gov (United States)

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

    2016-01-01

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

  6. Comparative field efficacy of newly developed formulations of larvicides against Aedes aegypti (L.) (Diptera: Culicidae).

    Science.gov (United States)

    Thavara, Usavadee; Tawatsin, Apiwat; Chompoosri, Jakkrawarn; Bhakdeenuan, Payu; Khamsawads, Chayada; Sangkitporn, Somchai; Siriyasatien, Padet; Asavadachanukorn, Preecha; Boonmuen, Saibua; Mulla, Mir S

    2013-09-01

    Aedes aegypti (L.) is known as vector of dengue and chikungunya fever. Larvicides are used to control this vector. We evaluated the efficacy of newly developed formulations of larvicides to control Ae. aegypti under field conditions for 24 weeks post single application. Mosdop P and Mosdop TB containing diflubenzuron (2% and 40 mg/tablet, respectively) as the active ingredient, were applied at a dosage of 0.1 mg a.i./1 and Mosquit TB10, Mosquit TB100 and Temecal containing temephos (1%, 10% and 1%, respectively) as the active ingredient were applied at a dosage of 1 mg active ingredent (a.i.) to 200 liter water storage jars. Two water regimens were used in the jars: in one regimen the jar was kept full of water all the time and in the other regimen a full jar had half the volume removed and refilled weekly. The larvicidal efficacy was reported as the level of inhibition of emergence (IE%) calculated based on the pupal skins in the jars versus the original number of larvae added. Mosdop P, Mosdop TB, Mosquit TB10, Mosquit TB100 and Temecal showed complete larvicidal efficacy (100% IE) in the constantly full jars for 16, 17, 14, 20 and 13 weeks posttreatment, respectively; in the jars where half the volum of water was replaced weekly, the larvicides had complete larvicidal efficacy (100% IE) for 19, 20, 17, 24 and 15 weeks post-treatment, respectively. The five larvicide regimens evaluated in this study are effective for controlling Ae. aegypti larvae. PMID:24437310

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2014-08-01

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

  10. Oviposition activity of Aedes aegypti L. (Diptera: Culicidae) in response to different organic infusions.

    Science.gov (United States)

    Santos, Eloína; Correia, Juliana; Muniz, Luciana; Meiado, Marcos; Albuquerque, Cleide

    2010-01-01

    The present study investigates new sources of infusion as an oviposition attractant for Aedes aegypti L. Infusions with fetid and non-fetid odors were compared as an oviposition stimulant. Traps baited with infusions of dehydrated cashew leaves (Anacardium occidentale), potato peels (Solanum tuberosum) and graminea (Panicum maximum) were compared as attractants, and the effect of odor (fetid and unfetid) on attractiveness was tested. Oviposition activity changed significantly according to the concentration and type of infusion (F = 4.1279; gl = 2; P = 0.0231). A larger number of eggs were observed in cups containing 50% A. occidentale (non-fetid odor) and 30% P. maximum (fetid odor). When compared in the same cage, comparable oviposition was found between A. occidentale and P. maximum. Moreover, approximately 20% more eggs were recorded in the infusion without odor when compared to the grass infusion and water. These findings suggest A. occidentale as a new stimulant for use in ovitraps for Aedes surveillance and control, with the benefit of having an agreeable odor. PMID:20498970

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

    OpenAIRE

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

    2014-01-01

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

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

    OpenAIRE

    MUTHUSAMY, R; M S Shivakumar

    2015-01-01

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

  13. Larvicidal Activity of Essential Oils from the Leaves and Fruits of Nutmeg (Myristica fragrans Houtt Against Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Anne Carolina

    2016-07-01

    Full Text Available The aim of this research was to examine the larvicidal activity of essential oil (EO extracted from nutmeg (Myristica fragrans Houtt leaves and fruits by steam distillation, and to analyze its chemical compounds. The EO yield of nutmeg leaves and fruits collected from the same tree was 0.66% and 0.30%, respectively. Larvicidal tests with the EO were carried out against Aedes aegypti (L. (Diptera: Culicidae. The concentrations of nutmeg EO used for the larvicidal assay were 50, 100, 150, 200, and 250 μg/mL. The results showed that fruit oil was more toxic than the leaf oil. LC50 values of leaf and fruit EOs were 133.8 and 110.1 µg/mL, respectively. The chromatogram of GC-MS showed that the chemical components in nutmeg leaf and fruit EOs were dominated by α-pinene, sabinene, β-pinene, delta-3-carene, limonene, β-phellandrene, α-terpinolene, linalool, safrole, croweacin, and myristicin.

  14. The Influence of Ambient Temperature on the Susceptibility of Aedes aegypti (Diptera: Culicidae) to the Pyrethroid Insecticide Permethrin.

    Science.gov (United States)

    Whiten, Shavonn R; Peterson, Robert K D

    2016-01-01

    Insecticides are the most common strategy used for the management of mosquitoes. Changes in ambient temperature can alter the toxicity of insecticides to ectothermic organisms. Studies show organophosphate insecticides exhibit a positive correlation between ambient temperature and mortality for many insect species, and carbamate insecticides exhibit a slightly negative correlation between ambient temperature and mortality. Pyrethroid insecticides exhibit a distinctly negative correlation between increasing ambient temperature and mortality for insects. However, this relationship has not been systematically studied for adult mosquitoes. Therefore, we examined the influence of temperature on the susceptibility of adult Aedes aegypti L. (Diptera: Culicidae) when exposed to permethrin. The median lethal concentration, LC50, was estimated for adult Ae. aegypti when exposed to eight concentrations of permethrin (ranging from 0.06–0.58 ng/cm2) at each of the following temperatures—16, 23, 26, 30, 32, and 34C—for 24 h in bottle assays. The estimated LC50 for each temperature was 0.26, 0.36, 0.36, 0.45, 0.27, and 0.31 ng/cm2, respectively. Results indicated a negative correlation between temperature and mortality from 16 to 30C, a positive correlation between temperature and mortality from 30 to 32C, and a negative correlation between temperature and mortality from 32 to 34C. If mosquito populations are expanding in space and time because of increased ambient temperatures and cannot be managed as effectively with pyrethroids, the spread of mosquito-borne diseases may pose considerable additional risk to public health.

  15. Essential oils with insecticidal activity against larvae of Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Vera, Sharon Smith; Zambrano, Diego Fernando; Méndez-Sanchez, Stelia Carolina; Rodríguez-Sanabria, Fernando; Stashenko, Elena E; Duque Luna, Jonny E

    2014-07-01

    Insecticidal activity of the essential oils (EOs) isolated from Tagetes lucida, Lippia alba, Lippia origanoides, Eucalyptus citriodora, Cymbopogon citratus, Cymbopogon flexuosus, Citrus sinensis, Swinglea glutinosa, and Cananga odorata aromatic plants, grown in Colombia (Bucaramanga, Santander), and of a mixture of L. alba and L. origanoides EOs were evaluated on Aedes (Stegomyia) aegypti Rockefeller larvae. The EOs were extracted by microwave-assisted hydrodistillation and characterized by gas chromatography-mass spectrometry (GC-MS). The main components of the EOs were identified using their linear retention indices and mass spectra. The lethal concentrations (LCs) of the EOs were determined between the third and fourth instar of A. aegypti. LC50 was determined by probit analysis using mortality rates of bioassays. All essential oils tested showed insecticidal activity. The following values were obtained for C. flexuosus (LC50 = 17.1 ppm); C. sinensis (LC50 = 20.6 ppm); the mixture of L. alba and L. origanoides (LC50 = 40.1 ppm); L. alba (LC50 = 42.2 ppm); C. odorata (LC50 = 52.9 ppm); L. origanoides (LC50 = 53.3 ppm); S. glutinosa (LC50 = 65.7 ppm); T. lucida (LC50 = 66.2 ppm); E. citriodora (LC50 = 71.2 ppm); and C. citratus (LC50 = 123.3 ppm). The EO from C. flexuosus, with citral (geranial + neral) as main component, showed the highest larvicidal activity. PMID:24781026

  16. Insecticide resistance and genetic variability in natural populations of Aedes (Stegomyia aegypti (Diptera: Culicidae from Colombia

    Directory of Open Access Journals (Sweden)

    Oscar A. Aguirre-Obando

    2015-02-01

    Full Text Available Mosquito control prevails as the most efficient method to protect humans from the dengue virus, despite recent efforts to find a vaccine for this disease. We evaluated insecticide resistance and genetic variability in natural populations of Aedes aegypti (Linnaeus, 1762 from Colombia. This is the first Colombian study examining kdr mutations and population structure. Bioassays with larvae of three mosquito populations (Armenia, Calarcá and Montenegro were performed according to the World Health Organization (WHO guidelines, using Temephos. For the analysis of the Val1016Ile mutation and genetic diversity, we sampled recently-emerged adults from four mosquito populations (Armenia, Calarcá, Montenegro and Barcelona. Following the WHO protocol, bioassays implemented with larvae showed resistance to Temephos in mosquito populations from Armenia (77% ± 2 and Calarcá (62% ± 14, and an incipient altered susceptibility at Montenegro (88% ± 8. The RR95 of mosquito populations ranged from 3.7 (Montenegro to 6.0 (Calarca. The Val1016Ile mutation analysis of 107 genotyped samples indicates that 94% of the specimens were homozygous for the wild allele (1016Val and 6% were heterozygous (Val1016Ile. The 1016Ile allele was not found in Barcelona. Genetic variability analysis found three mitochondrial lineages with low genetic diversity and gene flow. In comparison with haplotypes from the American continent, those from this study suggest connections with Mexican and North American populations. These results confirm that a continuous monitoring and managing program of A. aegypti resistance in the state of Quindío is required.

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

    Directory of Open Access Journals (Sweden)

    Claudia Andrea Núñez

    2016-06-01

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

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

    OpenAIRE

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

    2007-01-01

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

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

    Science.gov (United States)

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

    2014-02-01

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

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

    Directory of Open Access Journals (Sweden)

    Ima Aparecida Braga

    2005-07-01

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

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

    Science.gov (United States)

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

    2013-01-01

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

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

    Science.gov (United States)

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

    2014-02-01

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

  3. Evaluation of Andrographis paniculata Burm.f. (Family:Acanthaceae) extracts against Culex quinquefasciatus (Say.) and Aedes aegypti (Linn.) (Diptera:Culicidae)

    Institute of Scientific and Technical Information of China (English)

    Marimuthu Govindarajan

    2011-01-01

    Objective:To investigate the larvicidal and ovicidal efficacy of different extracts of Andrographis paniculata (A. paniculata) against Culex quinquefasciatus (Cx. quinquefasciatus) Say and Aedes aegypti (Ae. aegypti ) L. (Diptera:Culicidae). Methods:Larvicidal efficacy of the crude leaf extracts of A. paniculata with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the early third instar larvae of Cx. quinquefasciatus and Ae. aegypti. The ovicidal activity was determined against two mosquito species to various concentrations ranging from 50-300 ppm under the laboratory conditions. Results:The benzene, hexane, ethyl acetate, methanol and chloroform leaf extract of A. paniculata was found to be more effective against Cx. quinquefasciatus than Ae. aegypti. The LC50 values were 112.19, 137.48, 118.67, 102.05, 91.20 ppm and 119.58, 146.34, 124.24, 110.12, 99.54 ppm respectively. Among five tested solvent, methanol and ethyl acetate crude extract was found to be most effective for ovicidal activity against two mosquito species. The extract of methanol and ethyl acetate exerted 100%mortality at 200 ppm against Cx. quinquefasciatus and at 250 ppm against Ae. aegypti. Conclusions:From the results it can be concluded the crude extract of A. paniculata was a potential for controlling Cx. quinquefasciatus and Ae. aegypti mosquitoes.

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

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2011-06-01

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

  5. 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...

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

    OpenAIRE

    Claudia Andrea Núñez; Christian Raúl González; Víctor Obreque; Brenda Riquelme; Carolina Reyes; Mabel Rojas

    2016-01-01

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

  7. Synthesis and biological activity of acetates of copper (II and iron (III for the control of Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Jéssica V. Nardeli

    2012-06-01

    Full Text Available This work aimed to the synthesis of basic acetates of Cu (II and Fe(III against larvae of Aedes aegypti and Gram negative and Gram positive. The transition metal ions Cu (II and Fe (III have bactericidal activity and are toxic to Aedes aegypti larvae in the eggs and larval stages of initial, precludes the eggs hatch and slow reproductive cycle of the insect. The theme investigates the importance of carboxyl groups in complex formation, transport and cellular internalization of the toxic ions. It is known that the bactericide or insecticide activity is due to metal ions and Cu (IIor Fe (III.

  8. [Morphology and cytochemistry of Aedes aegypti's cell cultures (Diptera: Culicidae) and susceptibility to Leishmania panamensis (Kinetoplastida: Trypanosomatidae)].

    Science.gov (United States)

    Miranda, Alfonso Arturo; Sarmiento, Ladys; Caldas, María Leonor; Zapata, Cristina; Bello, Felio Jesús

    2008-06-01

    Morphology and cytochemistry of Aedes aegypti's cell cultures (Diptera: Culicidae) and susceptibility to Leishmania panamensis (Kinetoplastida: Trypanosomatidae). The first cellular line of Aedes aegypti was developed by Grace in 1966; afterwards, other cellular lines of this species have been generated. These have been used for the study of pathogenic organisms like viruses, bacteria and parasites, which demonstrates their importance in biomedical applications. This research describes, for the first time, some cytochemical characteristics of A. aegypti cell cultures, that were infected with (MHOM/CO/87CL412) strain of Leishmania panamensis. A morphological study of the cell culture was also carried out. Maintenance of the cell culture, parasites and infection in vitro were carried out in the Laboratory of Entomology, Cell Biology and Genetics of the Universidad de La Salle. The cell cultures infected with the parasite were maintained in a mixture of mediums Grace/L15, supplemented with 10 % fetal bovine serum (FBS) at pH 6.8 and a temperature of 26 degrees C, during 3, 6 and 9 post-infection days. After this, these cell cultures were processed through High Resolution Light Microscopy (HRLM) and Transmission Electron Microscopy (TEM) based on standard protocols defined by the Group of Microscopy and Image Analyses of the Instituto Nacional de Salud. Semi-fine slices of 1 microm colored with toluidine blue were used for the morphological analysis of the culture, and ultra fine cuts of 60 to 90 nm stained with uranyl acetate and lead citrate where used for the ultrastructural study. In addition, PAS and peroxidase staining was carried out in cells fixed with methanol. The morphometric study was analyzed with software ImageJ (NIH). In the semi-fine slices, small cells were observed showing fibroblastic appearance 10.84 +/- 2.54 microm in length and 5.31 +/- 1.26 microm wide; other cells had epithelial appearance with a great peripheral nucleus, voluminous and

  9. Morphological changes in the midgut of Aedes aegypti L. (Diptera: Culicidae) larvae following exposure to an Annona coriacea (Magnoliales: Annonaceae) extract.

    Science.gov (United States)

    Costa, M S; Pinheiro, D O; Serrão, J E; Pereira, M J B

    2012-08-01

    Bioinsecticides are important in the control of disease vectors, but data regarding their physiological effects on target insects are incomplete. This study describes morphological changes that occur in the midgut of third instar Aedes aegypti L. (Diptera: Culicidae) following treatment with a methanolic extract of Annona coriacea (Magnoliales: Annonaceae). Dissected midguts were subdivided into anterior and posterior regions and analyzed by light and scanning electron microscopy. Insects exposed to the extract displayed intense, destructive cytoplasmic vacuolization in columnar and regenerative midgut cells. The apical surfaces of columnar cells exhibited cytoplasmic protrusions oriented toward the lumen, suggesting that these cells could be involved in apocrine secretory processes and/or apoptosis. We report that A. coriacea extracts induced morphological alterations in the midgut of A. aegypti midgut larvae, supporting the use of plant extracts for control of the dengue vector.

  10. 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.

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

    Directory of Open Access Journals (Sweden)

    Wanessa Porto Tito Gambarra

    2013-04-01

    Full Text Available INTRODUCTION: The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypti collected in municipalities of the State of Paraíba. METHODS: Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a./L and multiple concentrations that caused mortalities between 5% and 99%. Electrophoresis of isoenzymes was used to verify the patterns of esterase activity among populations of the vector. RESULTS: All populations of Aedes aegypti were resistant to temephos, presenting a resistance rate (RR greater than 20. The greatest lethal dose 50% of the sample (CL50 was found for the municipality of Lagoa Seca, approximately forty-one times the value of CL50 for the Rockefeller population. The populations characterized as resistant showed two to six regions of α and β-esterase, called EST-1 to EST-6, while the susceptible population was only seen in one region of activity. CONCLUSIONS: Aedes aegypti is widely distributed and shows a high degree of resistance to temephos in all municipalities studied. In all cases, esterases are involved in the metabolism and, consequently, in the resistance to temephos.

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

    Directory of Open Access Journals (Sweden)

    Wanessa Porto Tito Gambarra

    2013-09-01

    Full Text Available INTRODUCTION: The need for studies that describe the resistance patterns in populations of Aedes aegypti (Linnaeus in function of their region of origin justified this research, which aimed to characterize the resistance to temephos and to obtain information on esterase activity in populations of Aedes aegypti collected in municipalities of the State of Paraíba. METHODS: Resistance to temephos was evaluated and characterized from the diagnostic dose of 0.352mg i.a./L and multiple concentrations that caused mortalities between 5% and 99%. Electrophoresis of isoenzymes was used to verify the patterns of esterase activity among populations of the vector. RESULTS: All populations of Aedes aegypti were resistant to temephos, presenting a resistance rate (RR greater than 20. The greatest lethal dose 50% of the sample (CL50 was found for the municipality of Lagoa Seca, approximately forty-one times the value of CL50 for the Rockefeller population. The populations characterized as resistant showed two to six regions of α and β-esterase, called EST-1 to EST-6, while the susceptible population was only seen in one region of activity. CONCLUSIONS: Aedes aegypti is widely distributed and shows a high degree of resistance to temephos in all municipalities studied. In all cases, esterases are involved in the metabolism and, consequently, in the resistance to temephos.

  13. Papyracillic acid and its derivatives as biting deterrents against Aedes aegypti(Diptera: Culicidae): structure–activity relationships

    Science.gov (United States)

    Aedes aegypti L. is the major vector of the arboviruses responsible for dengue fever, one of the most devastating human diseases. Papyracillic acid, the main phytotoxin produced by Ascochyta agropyrina var. nana, was evaluated in a preliminary screening together with other fungal phytotoxins, cyclo...

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

    Science.gov (United States)

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

    2016-06-01

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

  15. Laboratory and field evaluation of the effects of the neonicotinoid imidacloprid on the oviposition response of Aedes (Stegomyia aegypti Linnaeus (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Gloria Elsa Antonio-Arreola

    2011-12-01

    Full Text Available In this paper, we assessed the suitability of using the neonicotinoid imidacloprid with standard ovitraps by evaluating the ovicidal properties of imidacloprid and its influence on the oviposition response of gravid females of Aedes (Stegomyia aegypti Linnaeus (Diptera: Culicidae. First, we calculated the imidacloprid lethal dose 99 (LD99 by exposing third instar larvae of the target species to different concentrations of the insecticide. Next, Ae. aegypti eggs were exposed to the imidacloprid LD99 for 24 h and hatching inhibition was recorded. Finally, we investigated any potential repellent effect of the imidacloprid solution on the oviposition response of gravid Aedes females in field and laboratory conditions. The LD99 obtained from larvae tests proved to be sufficient to keep any exposed eggs from hatching. No repellent effect was observed; females laid as many eggs in imidacloprid-treated ovitraps as in traps containing either clean water or temephos-treated water in both field and laboratory conditions. Our results indicate that imidacloprid is a suitable insecticide for treating ovitraps against Ae. aegypti.

  16. Atividade larvicida do óleo de Anacardium humile Saint Hill sobre Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae Larvicidal activity of Anacardium humile Saint Hill oil on Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Karla Rejane de Andrade Porto

    2008-12-01

    Full Text Available O objetivo deste estudo foi avaliar o potencial do cajuzinho do cerrado (Anacardium humile sobre larvas de Aedes aegypti. Os extratos hexânico, etanólico, aquoso e o óleo das folhas foram obtidos do material vegetal coletado em fragmento de cerrado. Estes foram testados nas concentrações 1%; 0,5%, 0,25%, 0,125%, 0,05% e 0,0125% diluídas em dimetil sulfóxido 1%. A contagem das larvas mortas foi realizada após 24 horas. Utilizou-se o método Probit de análise para obtenção das CL50 e respectivos intervalos de confiança. Conclui-se que apenas o óleo extraído de folhas de Anacardium humile causa 100% de mortalidade em larvas de 4º estádio de Aedes aegypti nas concentrações até 0,125%, o que parece indicar que os ingredientes ativos estão na fase mais apolar. O que indica a potencialidade de uso da planta como larvicida de Aedes aegypti, entretanto, novos testes deverão ser conduzidos utilizando outros órgãos vegetais, assim como outros métodos e solventes utilizados na extração.The objective of this study was to evaluate the potential of Anacardium humile (monkey nuts against Aedes aegypti larvae. Hexane, ethanol and aqueous extracts and oil from leaves were obtained from plant material collected from the Brazilian savanna. These were tested at concentrations of 1%, 0.5%, 0.25%, 0.125%, 0.05% and 0.0125%, diluted in 1% dimethyl sulfoxide. The dead larvae were counted 24 hours later. The Probit analysis method was used to obtain the LC50 and the respective confidence intervals. The conclusion was that only the oil extracted from Anacardium humile leaves caused 100% mortality among fourth-instar Aedes aegypti larvae, using concentrations of up to 0.125%. This seems to indicate that the active ingredients are present in the most apolar phase. This indicates that this plant has potential use as a larvicide against Aedes aegypti. However, new tests should be carried out using other plant organs, as well as using other methods

  17. 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.

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

    OpenAIRE

    Josiane Somariva Prophiro; Onilda Santos Silva; Jonny Edward Duque Luna; Carla Fernanda Piccoli; Luiz Alberto Kanis; Mario Antonio Navarro da Silva

    2011-01-01

    INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggr...

  19. 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.

  20. Effect of stalk and leaf extracts from Euphorbiaceae species on Aedes aegypti (Diptera, Culicidae) larvae Efeito dos extratos de caule e folha de espécies de Euphorbiaceae sobre larvas de Aedes aegypti (Diptera, Culicidae)

    OpenAIRE

    Maria Goretti Araújo Lima; Ismália Cassandra Costa Maia; Bruna Dantas de Sousa; Selene Maia de Morais; Sílvia Maria de Freitas

    2006-01-01

    The objective of this study was to evaluate the larvicidal activity of essential oil aqueous solutions (hydrolates) obtained by steam distillation of stalks and leaves of Croton argyrophylloides, Croton nepetaefolius, Croton sonderianus and Croton zehntneri against Aedes aegypti larvae. Twenty-five larvae of third instar were placed in plastic beckers, containing the hydrolates (50 mL), in a four repetitions scheme. Water was used as control and the number of dead larvae was counted after 24 ...

  1. 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

  2. Larvicidal and Pupicidal Activities of Alizarin Isolated from Roots of Rubia cordifolia Against Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae).

    Science.gov (United States)

    Gandhi, M R; Reegan, A D; Ganesan, P; Sivasankaran, K; Paulraj, M G; Balakrishna, K; Ignacimuthu, S; Al-Dhabi, N A

    2016-08-01

    The mosquitocidal activities of different fractions and a compound alizarin from the methanol extract of Rubia cordifolia roots were evaluated on larvae and pupae of Culex quinquefasciatus Say and Aedes aegypti (L.) (Diptera: Culicidae). Larvae and pupae were exposed to concentrations of 2.5, 5.0, 7.5 and 10 ppm for fractions and 0.5, 1.0, 1.5 and 2.0 ppm for compound. After 24 h, the mortality was assessed and the LC50 and LC90 values were estimated for larvae and pupae. Among the 23 fractions screened, fraction 2 from the methanol extract of R. cordifolia showed good mosquitocidal activity against C. quinquefasciatus and A. aegypti. LC50 and LC90 values of fraction 2 were 3.53 and 7.26 ppm for C. quinquefasciatus and 3.86 and 8.28 ppm for A. aegypti larvae, and 3.76 and 7.50 ppm for C. quinquefasciatus and 3.92 and 8.05 ppm for A. aegypti pupae, respectively. Further, the isolated compound alizarin presented good larvicidal and pupicidal activities. LC50 and LC90 values of alizarin for larvae were 0.81 and 3.86 ppm against C. quinquefasciatus and 1.31 and 6.04 ppm for A. aegypti larvae, respectively. Similarly, the LC50 and LC90 values of alizarin for pupae were 1.97 and 4.79 ppm for C. quinquefasciatus and 2.05 and 5.59 ppm for A. aegypti pupae, respectively. The structure of the isolated compound was identified on the basis of spectroscopic analysis and compared with reported spectral data. The results indicated that alizarin could be used as a potential larvicide and pupicide.

  3. Genetic deviation in geographically close populations of the dengue vector Aedes aegypti (Diptera: Culicidae): influence of environmental barriers in South India.

    Science.gov (United States)

    Vadivalagan, Chithravel; Karthika, Pushparaj; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Paulpandi, Manickam; Madhiyazhagan, Pari; Wei, Hui; Aziz, Al Thabiani; Alsalhi, Mohamad Saleh; Devanesan, Sandhanasamy; Nicoletti, Marcello; Paramasivan, Rajaiah; Dinesh, Devakumar; Benelli, Giovanni

    2016-03-01

    Mosquitoes are vectors of devastating pathogens and parasites, causing millions of deaths every year. Dengue is a mosquito-borne viral infection found in tropical and subtropical regions around the world. Recently, dengue transmission has strongly increased in urban and semiurban areas, becoming a major international public health concern. Aedes aegypti (Diptera: Culicidae) is a primary vector of dengue. Shedding light on genetic deviation in A. aegypti populations is of crucial importance to fully understand their molecular ecology and evolution. In this research, haplotype and genetic analyses were conducted using individuals of A. aegypti from 31 localities in the north, southeast, northeast and central regions of Tamil Nadu (South India). The mitochondrial DNA region of cytochrome c oxidase 1 (CO1) gene was used as marker for the analyses. Thirty-one haplotypes sequences were submitted to GenBank and authenticated. The complete haplotype set included 64 haplotypes from various geographical regions clustered into three groups (lineages) separated by three fixed mutational steps, suggesting that the South Indian Ae. aegypti populations were pooled and are linked with West Africa, Columbian and Southeast Asian lineages. The genetic and haplotype diversity was low, indicating reduced gene flow among close populations of the vector, due to geographical barriers such as water bodies. Lastly, the negative values for neutrality tests indicated a bottle-neck effect and supported for low frequency of polymorphism among the haplotypes. Overall, our results add basic knowledge to molecular ecology of the dengue vector A. aegypti, providing the first evidence for multiple introductions of Ae. aegypti populations from Columbia and West Africa in South India. PMID:26627691

  4. Evaluation of two sweeping methods for estimating the number of immature Aedes aegypti (Diptera: Culicidae in large containers

    Directory of Open Access Journals (Sweden)

    Margareth Regina Dibo

    2013-07-01

    Full Text Available Introduction Here, we evaluated sweeping methods used to estimate the number of immature Aedes aegypti in large containers. Methods III/IV instars and pupae at a 9:1 ratio were placed in three types of containers with, each one with three different water levels. Two sweeping methods were tested: water-surface sweeping and five-sweep netting. The data were analyzed using linear regression. Results The five-sweep netting technique was more suitable for drums and water-tanks, while the water-surface sweeping method provided the best results for swimming pools. Conclusions Both sweeping methods are useful tools in epidemiological surveillance programs for the control of Aedes aegypti.

  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. Neem oil increases the efficiency of the entomopathogenic fungus Metarhizium anisopliae for the control of Aedes aegypti (Diptera: Culicidae) larvae

    OpenAIRE

    Gomes, Simone A.; Paula, Adriano R; Ribeiro, Anderson; Moraes, Catia O. P.; Santos, Jonathan W. A. B.; Silva, Carlos P; Samuels, Richard I

    2015-01-01

    Background Entomopathogenic fungi are potential candidates for use in integrated vector management and many isolates are compatible with synthetic and natural insecticides. Neem oil was tested separately and in combination with the entomopathogenic fungus Metarhizium anisopliae against larvae of the dengue vector Aedes aegypti. Our aim was to increase the effectiveness of the fungus for the control of larval mosquito populations. Methods Commercially available neem oil was used at concentrati...

  7. 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...

  8. Spatial and Temporal Variation in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Numbers in the Yogyakarta Area of Java, Indonesia, With Implications for Wolbachia Releases.

    Science.gov (United States)

    Tantowijoyo, W; Arguni, E; Johnson, P; Budiwati, N; Nurhayati, P I; Fitriana, I; Wardana, S; Ardiansyah, H; Turley, A P; Ryan, P; O'Neill, S L; Hoffmann, A A

    2016-01-01

    of mosquito vector populations, particularly through Wolbachia endosymbionts. The success of these strategies depends on understanding the dynamics of vector populations. In preparation for Wolbachia releases around Yogyakarta, we have studied Aedes populations in five hamlets. Adult monitoring with BioGent- Sentinel (BG-S) traps indicated that hamlet populations had different dynamics across the year; while there was an increase in Aedes aegypti (L.) and Aedes albopictus (Skuse) numbers in the wet season, species abundance remained relatively stable in some hamlets but changed markedly (>2 fold) in others. Local rainfall a month prior to monitoring partly predicted numbers of Ae. aegypti but not Ae. albopictus. Site differences in population size indicated by BG-S traps were also evident in ovitrap data. Egg or larval collections with ovitraps repeated at the same location suggested spatial autocorrelation (<250 m) in the areas of the hamlets where Ae. aegypti numbers were high. Overall, there was a weak negative association (r<0.43) between Ae. aegypti and Ae. albopictus numbers in ovitraps when averaged across collections. Ae. albopictus numbers in ovitraps and BG-S traps were positively correlated with vegetation around areas where traps were placed, while Ae. aegypti were negatively correlated with this feature. These data inform intervention strategies by defining periods when mosquito densities are high, highlighting the importance of local site characteristics on populations, and suggesting relatively weak interactions between Ae. aegypti and Ae. albopictus. They also indicate local areas within hamlets where consistently high mosquito densities may influence Wolbachia invasions and other interventions.

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

    Directory of Open Access Journals (Sweden)

    Normah Awang

    2012-01-01

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

  10. 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.

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

    Science.gov (United States)

    Govindarajan, Marimuthu; Sivakumar, Rajamohan

    2014-04-01

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

  12. Flavivirus susceptibility in Aedes aegypti.

    Science.gov (United States)

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

    2002-01-01

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

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

    Institute of Scientific and Technical Information of China (English)

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

    2011-01-01

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

  14. Spatial and Temporal Variation in Aedes aegypti and Aedes albopictus (Diptera: Culicidae) Numbers in the Yogyakarta Area of Java, Indonesia, With Implications for Wolbachia Releases.

    Science.gov (United States)

    Tantowijoyo, W; Arguni, E; Johnson, P; Budiwati, N; Nurhayati, P I; Fitriana, I; Wardana, S; Ardiansyah, H; Turley, A P; Ryan, P; O'Neill, S L; Hoffmann, A A

    2016-01-01

    of mosquito vector populations, particularly through Wolbachia endosymbionts. The success of these strategies depends on understanding the dynamics of vector populations. In preparation for Wolbachia releases around Yogyakarta, we have studied Aedes populations in five hamlets. Adult monitoring with BioGent- Sentinel (BG-S) traps indicated that hamlet populations had different dynamics across the year; while there was an increase in Aedes aegypti (L.) and Aedes albopictus (Skuse) numbers in the wet season, species abundance remained relatively stable in some hamlets but changed markedly (>2 fold) in others. Local rainfall a month prior to monitoring partly predicted numbers of Ae. aegypti but not Ae. albopictus. Site differences in population size indicated by BG-S traps were also evident in ovitrap data. Egg or larval collections with ovitraps repeated at the same location suggested spatial autocorrelation (hamlets where Ae. aegypti numbers were high. Overall, there was a weak negative association (rhamlets where consistently high mosquito densities may influence Wolbachia invasions and other interventions. PMID:26576934

  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. Detection of multiple blood feeding in Aedes aegypti (Diptera: Culicidae) during a single gonotrophic cycle using a histologic technique.

    Science.gov (United States)

    Scott, T W; Clark, G G; Lorenz, L H; Amerasinghe, P H; Reiter, P; Edman, J D

    1993-01-01

    We evaluated a histologic technique for its usefulness in detecting multiple blood feeding by Aedes aegypti (L.) in a single gonotrophic cycle. To standardize the procedure, we carried out a laboratory study in which 166 mosquitoes imbibed two blood meals at known intervals. Eighty percent (78/98) of the multiple meals were detected when the interval between meals was from 1 to mosquitoes took their last meal the day before capture, and most multiple feeders fed twice on consecutive days. A dark line of digested blood, or heme, around the first meal and a physical separation between meals were the most useful histologic parameters for detecting multiple feeding in wild Ae. aegypti. An association of multiple feeding with advanced stages of oocyte development suggests that, at the time of collection, most Ae. aegypti from the study site had fed twice in each gonotrophic cycle. We conclude that, although it is labor intensive, histologic examination is an appropriate technique for a longitudinal, community-wide survey of multiple feeding by Ae. aegypti. PMID:8433350

  17. Vacant Lots: Productive Sites for Aedes (Stegomyia) aegypti (Diptera: Culicidae) in Mérida City, México

    Science.gov (United States)

    BAAK-BAAK, CARLOS M.; ARANA-GUARDIA, ROGER; CIGARROA-TOLEDO, NOHEMI; LOROÑO-PINO, MARÍA ALBA; REYES-SOLIS, GUADALUPE; MACHAIN-WILLIAMS, CARLOS; BEATY, BARRY J.; EISEN, LARS; GARCÍA-REJÓN, JULIÁN E.

    2014-01-01

    We assessed the potential for vacant lots and other non-residential settings to serve as source environments for Aedes (Stegomyia) aegypti (L.) in Mérida City, México. Mosquito immatures were collected, during November 2011 – June 2013, from residential premises (n = 156 site visits) and non-residential settings represented by vacant lots (50), parking lots (18), and streets/sidewalks (28). Collections totaled 46,025 mosquito immatures of 13 species. Ae. aegypti was the most commonly encountered species accounting for 81.0% of total immatures, followed by Culex quinquefasciatus Say (12.1%). Site visits to vacant lots (74.0%) were more likely to result in collection of Ae. aegypti immatures that residential premises (35.9%). Tires accounted for 75.5% of Ae. aegypti immatures collected from vacant lots. Our data suggest that vacant lots should be considered for inclusion in mosquito surveillance and control efforts in Mérida City, as they often are located near homes, commonly have abundant vegetation, and frequently harbor accumulations of small and large discarded water-holding containers that we now have demonstrated to serve as development sites for immature mosquitoes. Additionally, we present data for associations of immature production with various container characteristics, such as storage capacity, water quality and physical location in the environment. PMID:24724299

  18. Oviposition activity and seasonal pattern of a population of Aedes (Stegomyia aegypti (L. (Diptera: Culicidae in subtropical Argentina

    Directory of Open Access Journals (Sweden)

    Micieli María Victoria

    2003-01-01

    Full Text Available Monthly oviposition activity and the seasonal density pattern of Aedes aegypti were studied using larvitraps and ovitraps during a research carried out by the Public Health Ministry of Salta Province, in Tartagal, Aguaray and Salvador Mazza cities, in subtropical Argentina. The A. aegypti population was active in both dry and wet seasons with a peak in March, accordant with the heaviest rainfall. From May to November, the immature population level remained low, but increased in December. Ae. aegypti oviposition activity increased during the fall and summer, when the relative humidity was 60% or higher. Eggs were found in large numbers of ovitraps during all seasons but few eggs were observed in each one during winter. The occurrence and the number of eggs laid were variable when both seasons and cities were compared. The reduction of the population during the winter months was related to the low in the relative humidity of the atmosphere. Significant differences were detected between oviposition occurrences in Tartagal and Aguaray and Salvador Mazza cities, but no differences in the number of eggs were observed. Two factors characterize the seasonal distribution pattern of Ae. aegypti in subtropical Argentina, the absence of a break during winter and an oviposition activity concomitant of the high relative humidity of the atmosphere.

  19. Isolation of Bacillus thuringiensis from the state of Amazonas, in Brazil, and screening against Aedes aegypti (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Joelma Soares-da-Silva

    2015-03-01

    Full Text Available We investigated the use of Bacillus thuringiensis isolated in the state of Amazonas, in Brazil, for the biological control of the dengue vector Aedes aegypti. From 25 soil samples collected in nine municipalities, 484 bacterial colonies were obtained, 57 (11.78% of which were identified as B. thuringiensis. Six isolates, IBt-03, IBt-06, IBt-07, IBt-28, IBt-30, and BtAM-27 showed insecticidal activity, and only BtAM-27 presents the five genes investigated cry4Aa, cry4Ba, cry10Aa, cry11Aa, and cry11Ba. The IBt-07 and IBt- 28, with lower LC50 values, showed equal toxicity compared to the standards. The isolates of B. thuringiensis from Amazonas constitute potential new means of biological control for A. aegypti, because of their larvicidal activity and the possibility that they may also contain new combinations of toxins.

  20. Larvicidal effect of dried leaf extracts from Pinus caribaea against Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae Efeito larvicida dos extratos de folhas secas de Pinus caribaea contra Aedes aegypti (Linnaeus, 1762 (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Luiz Alberto Kanis

    2009-08-01

    Full Text Available In this study, the larvicidal activity of dried leaf extracts from Pinus caribaea Morelet against Aedes aegypti was evaluated for the first time. Pinus caribaea extracts were obtained by macerating dried leaves in alkaline hydroethanol, ethanol and acetone solutions followed by evaporation under reduced pressure. The lignin content was quantified using the thioglycolic acid complexation method. Lethality bioassays (LC50 and LC90 were carried out in accordance with the recommendations of the World Health Organization. The results showed that the acetone extract from Pinus caribaea was more active, and that larvicidal activity was associated with lignin concentration.Neste trabalho foi avaliada pela primeira vez a atividade larvicida contra Aedes aegypti de extratos obtido a partir de folhas secas de Pinus caribae. Os extratos de Pinus caribaea foram obtidos a partir da maceração de folhas secas em solução hidroetanólica alcalina, etanol e acetona, seguido de evaporação sob pressão reduzida. O teor de lignina foi quantificado usando o método de complexação com ácido tioglicóliclo. Os ensaios de letalidade foram conduzidos de acordo com a recomendação da Organização Mundial da Saúde. Os resultados demonstraram que o extrato obtido com acetona foi mais ativo, e a atividade larvicida esta associada com a concentração de ligninas.

  1. Bioassay and biochemical studies of the status of pirimiphos-methyl and cypermethrin resistance in Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera: Culicidae) in Singapore.

    Science.gov (United States)

    Lee, R M L; Choong, C T H; Goh, B P L; Ng, L C; Lam-Phua, S G

    2014-12-01

    Aedes (Stegomyia) aegypti (Linnaeus) and Ae. (Stegomyia) albopictus (Skuse) were sampled from five regions of Singapore (Central, North East, North West, South East and South West) and tested with diagnostic concentrations of the technical grade insecticides, pirimiphos-methyl and cypermethrin. Biochemical assays were performed on the same populations of Ae. aegypti and Ae. albopictus to determine activities of detoxifying enzymes, including non-specific esterase (EST), monooxygenase (MFO) and acetylcholinesterase (AChE). The diagnostic test showed that all Ae. aegypti populations were susceptible to pirimiphos-methyl (mortality = 99 to 100%), but resistant to cypermethrin (mortality = 11 to 76%). Resistance to pirimiphos-methyl was observed in all Ae. albopictus populations (mortality = 49 to 74%) while cypermethrin resistance was detected in most Ae. albopictus populations (mortality = 40 to 75%), except those from Central (mortality = 86%) and South East (mortality = 94%) showing incipient resistance. The biochemical assays showed that there was significant enhancement (P aegypti populations. The biochemical assay results suggested that AChE could play a role in pirimiphos-methyl resistance of Ae. albopictus in South West, South East and North East regions. The small but significant increase in EST activities in Ae. aegypti from all regions suggest that it may play a role in the observed cypermethrin resistance.

  2. Aedes aegypti and Aedes albopictus (Diptera: Culicidae: coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization Aedes aegypti e Aedes albopictus (Diptera: Culicidae: coexistência e susceptibilidade ao temephos, em municípios com ocorrência de casos de dengue e diferentes características de urbanização

    Directory of Open Access Journals (Sweden)

    Josiane Somariva Prophiro

    2011-06-01

    Full Text Available INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggregation, using the variance-to-mean ratio (index of dispersion. Susceptibility to temephos was evaluated by estimation of the resistance ratios RR50 and RR95. Aedes aegypti samples were compared with the population Rockefeller and Aedes albopictus samples were compared with a population from the State of Santa Catarina and with the Rockefeller population. RESULTS: Coexistence between Aedes aegypti and Aedes albopictus and the aggregation of their eggs were observed at all the sites analyzed in the State of Paraná. CONCLUSIONS: All the Aedes aegypti populations from the State of Parana showed alteration in susceptibility status to the organophosphate temephos, revealing incipient resistance. Similarly, all the Aedes albopictus populations (States of Paraná and Santa Catarina presented survival when exposed to the organophosphate temephos.INTRODUÇÃO: O presente estudo teve como objetivo verificar a coexistência de populações de Aedes aegypti e de Aedes albopictus em municípios do Estado do Paraná e Santa Catarina com diferentes formas de urbanização, onde ocorrem casos de dengue, e avaliar a susceptibilidade ao organofosforado temephos. MÉTODOS: O número de ovos por ovitrampa foram contados (sem distinguir a espécie e colocados para eclosão e posterior identificação das espécies. A análise das populacões foi conduzida para determinar aleatoriedade e agregação usando a razão variância/média (índice de dispersão. A susceptibilidade ao

  3. Aedes aegypti and Aedes albopictus (Diptera: Culicidae): coexistence and susceptibility to temephos, in municipalities with occurrence of dengue and differentiated characteristics of urbanization Aedes aegypti e Aedes albopictus (Diptera: Culicidae): coexistência e susceptibilidade ao temephos, em municípios com ocorrência de casos de dengue e diferentes características de urbanização

    OpenAIRE

    Josiane Somariva Prophiro; Onilda Santos Silva; Jonny Edward Duque Luna; Carla Fernanda Piccoli; Luiz Alberto Kanis; Mario Antonio Navarro da Silva

    2011-01-01

    INTRODUCTION: The aim of the present study was to verify the coexistence between Aedes aegypti and Aedes albopictus populations in municipalities of the States of Paraná and Santa Catarina with different urbanization profiles where dengue occurs and evaluate their susceptibility to the organophosphate temephos. METHODS: The number of eggs per ovitrap were counted and incubated for hatching to identify the species. Data analysis of the populations was conducted to determine randomness and aggr...

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    Nildimar Alves Honório

    2003-03-01

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

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

    Directory of Open Access Journals (Sweden)

    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.

  7. 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

  8. 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.

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

    Science.gov (United States)

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

    2015-09-01

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

  10. First report on susceptibility of wild Aedes aegypti (Diptera: Culicidae) using Carapa guianensis (Meliaceae) and Copaifera sp. (Leguminosae).

    Science.gov (United States)

    Prophiro, Josiane S; da Silva, Mario Antonio Navarro; Kanis, Luiz A; da Rocha, Louyse Caroline B P; Duque-Luna, Jonny E; da Silva, Onilda S

    2012-02-01

    Oils of Carapa guianensis and Copaifera spp. are well known in the Amazonian region as natural insect repellent, and studies have reported their efficiency as larvicide against some laboratory mosquito species. However, in wild populations of mosquitoes, these oils have not yet been evaluated. Thus, the objective of this study was to investigate their efficiency as larvicide in wild populations of Aedes aegypti with a history of exposure to organophosphate. The susceptibility of larvae was determined under three different temperatures, 15°C, 20°C, and 30°C. For each test, 1,000 larvae were used (late third instar and early fourth instar-four replicates of 25 larvae per concentration). Statistical tests were used to identify significant differences. The results demonstrated that as the laboratory A. aegypti, the wild populations of A. aegypti were also susceptible to C. guianensis and Copaifera sp. oils. The lethal concentrations for Copaifera sp. ranged from LC(50) 47 to LC(90) 91 (milligrams per liter), and for C. guianensis, they were LC(50) 136 to LC(90) 551 (milligrams per liter). In relation to different temperature, the effectiveness of the oils on larvae mortality was directly related to the increase of temperature, and better results were observed for temperature at 25°C. The results presented here indicate the potential larvicidal activity of C. guianensis and species of Copaifera, in populations of A. aegypti from the wild. Therefore, the results presented here are very important since such populations are primarily responsible for transmitting the dengue virus in the environment.

  11. Variation in Aedes aegypti (Linnaeus (Diptera, Culicidae infestation in artificial containers in Caxias, state of Maranhão, Brazil

    Directory of Open Access Journals (Sweden)

    Joelma Soares-da-Silva

    2012-04-01

    Full Text Available INTRODUCTION: Dengue is a serious public health problem worldwide, with cases reported annually in tropical and subtropical regions. Aedes aegypti (Linnaeus, 1762, the main vector of dengue, is a domiciliary species with high dispersal and survival capacities and can use various artificial containers as breeding sites. We assessed potential container breeding sites of A. aegypti in the municipality of Caxias, Maranhão, Brazil. METHODS: In the initial phase, we analyzed 900 properties in 3 neighborhoods during the dry and rainy seasons (August-October 2005 and February-April 2006, respectively. During the second sampling period, September 2006-August 2007, we used 5 assessment cycles for 300 properties in a single neighborhood. RESULTS: During the dry and rainy seasons, water-storage containers comprised 55.7% (n = 1,970 and 48.5% (n = 1,836 of the total containers inspected, and showed the highest productivity of immature A. aegypti; we found 23.7 and 106.1 individuals/container, respectively, in peridomicile sites. In intradomicile sites, water-storage containers were also the most important breeding sites with 86.4% (n = 973 and 85.6% (n = 900 of all containers and a mean of 7.9 and 108.3 individuals/container in the dry and rainy seaso-October 2006 (1,342. The highest number of positives (70 was recorded in May, mostly (94% in storage containers. CONCLUSIONS: Storage containers are the principal and most productive A. aegypti breeding sites and are a major contributing factor to the maintenance of this vector in Caxias.

  12. The Insecticide Susceptibility Status of Aedes aegypti (Diptera: Culicidae) in Farm and Nonfarm Sites of Lagos State, Nigeria.

    Science.gov (United States)

    Ayorinde, A; Oboh, B; Oduola, A; Otubanjo, O

    2015-01-01

    Nigeria is one of the malaria-endemic countries. In Lagos State, Nigeria, various malaria vector control programs including the use of chemical insecticides are currently being implemented. This study was designed to provide information on the susceptibility status of some nontargeted vectors such as Aedes aegypti. Adult Ae. aegypti mosquitoes from two farm sites and a nonfarm site were exposed to World Health Organization test papers impregnated with Deltamethrin (0.05%), Permethrin (0.75%), and DDT (4%) insecticides. The Knockdown time (KdT50 and KdT95) and percentage mortality after 24 h post exposure were determined. In all the exposed mosquito populations to permethrin, mortality rate > 98% (susceptibility) was recorded, whereas mortality rates  98% (susceptibility) to deltamethrin were observed in the nonfarm site and farm sites mosquito populations, respectively. All the mosquito populations were resistant to DDT in 2 yr. The KdT50 of the populations to DDT increased (60.2-69.6) in one of the farm sites and the nonfarm site (68.9-199.96), while a decrease (243-63.4) in another farm site in 2 yr. Significant difference (P aegypti mosquitoes in the second year after exposure to deltamethrin and DDT. An increase in KdT95 after exposure to deltamethrin in the first year was recorded. Higher KdT values and lower mortality rates in Ae. aegypti populations in the nonfarm sites are indications there are existing factors selecting for insecticide resistance outside agricultural use of insecticides.

  13. Dispersal of Engineered Male Aedes aegypti Mosquitoes

    OpenAIRE

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

    2015-01-01

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

  14. Dispersal of Engineered Male Aedes aegypti Mosquitoes.

    OpenAIRE

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Samuels Richard I

    2011-05-01

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

  16. Effects of larval crowding on development time, survival and weight at metamorphosis in Aedes aegypti (Diptera: Culicidae Efectos del hacinamiento larval en el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis de Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Arnaldo Maciá

    2009-06-01

    Full Text Available The effects of larval crowding on survival, weight at metamorphosis and development time were assessed in the dengue mosquito, Aedes aegypti L., under a controlled environment. Larval cohorts were bred at 7 different densities (4, 8, 16, 32, 64, 128 and 256 larvae / 175 ml pot, while keeping constant water volume and food amount and quality, under controlled temperature and photoperiod. Natural detritus, mainly leaves, obtained from containers naturally colonized by A. aegypti, were used as a source of nutrients for larvae. Development time, mortality, mass at metamorphosis, and total biomass were recorded for each density. Development time ranged from 4 to 23 days in males, and from 5 to 24 in females, whereby larvae took longer to develop at 64 (females and 128 (males larvae per recipient. At high densities there was a male-biased sex proportion. At densities equal to or higher than 0.4 larvae/ml (0.32 larvae/cm² there was an increase of mortality. An inverse relationship between larval density and pupal weight was detected. Biomass per individual reached asymptotic values of about 1 mg/individual at a density of 128 individuals/pot (0.64 larvae/cm². This experiment shows that this southern strain of A. aegypti is sensitive to crowding in small containers.Los efectos del hacinamiento larval sobre el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis fueron estudiados en el mosquito del dengue, Aedes aegypti L., en el laboratorio. Se criaron cohortes de larvas en 7 densidades (4, 8, 16, 32, 64, 128 y 256 larvas/ recipiente de 175 ml mientras se mantuvo constante el volumen de agua y la calidad y cantidad de alimento, bajo fotoperíodo y temperatura controlados. Se usaron detritos naturales, principalmente hojas, obtenidos de contenedores colonizados naturalmente por A. aegypti como fuente de nutrientes para las larvas. En cada densidad se registraron el tiempo de desarrollo, la mortalidad, el peso en la metamorfosis y la

  17. 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)

    Suresh, Udaiyan; Murugan, Kadarkarai; Benelli, Giovanni; Nicoletti, Marcello; Barnard, Donald R; Panneerselvam, Chellasamy; Kumar, Palanisamy Mahesh; Subramaniam, Jayapal; Dinesh, Devakumar; Chandramohan, Balamurugan

    2015-04-01

    Mosquitoes are vectors of devastating pathogens and parasites, causing millions of deaths every year. Dengue is a mosquito-borne viral infection found in tropical and subtropical regions around the world. Recently, transmission has strongly increased in urban and semiurban areas, becoming a major international public health concern. Aedes aegypti (Diptera: Culicidae) is the primary vector of dengue. The use of synthetic insecticides to control Aedes mosquitoes lead to high operational costs and adverse nontarget effects. In this scenario, eco-friendly control tools are a priority. We proposed a novel method to synthesize silver nanoparticles using the aqueous leaf extract of Phyllanthus niruri, a cheap and nontoxic material. The UV-vis spectrum of the aqueous medium containing silver nanostructures showed a peak at 420 nm corresponding to the surface plasmon resonance band of nanoparticles. SEM analyses of the synthesized nanoparticles showed a mean size of 30-60 nm. EDX spectrum showed the chemical composition of the synthesized nanoparticles. XRD highlighted that the nanoparticles are crystalline in nature with face-centered cubic geometry. Fourier transform infrared spectroscopy (FTIR) of nanoparticles exhibited prominent peaks 3,327.63, 2,125.87, 1,637.89, 644.35, 597.41, and 554.63 cm(-1). In laboratory assays, the aqueous extract of P. niruri was toxic against larval instars (I-IV) and pupae of A. aegypti. LC50 was 158.24 ppm (I), 183.20 ppm (II), 210.53 ppm (III), 210.53 ppm (IV), and 358.08 ppm (pupae). P. niruri-synthesized nanoparticles were highly effective against A. aegypti, with LC50 of 3.90 ppm (I), 5.01 ppm (II), 6.2 ppm (III), 8.9 ppm (IV), and 13.04 ppm (pupae). In the field, the application of silver nanoparticles (10 × LC50) lead to A. aegypti larval reduction of 47.6%, 76.7% and 100%, after 24, 48, and 72 h, while the P. niruri extract lead to 39.9%, 69.2 % and 100 % of reduction, respectively. In adulticidal experiments, P. niruri extract

  18. 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...

  19. Ciclos de vida comparados de Aedes aegypti (Diptera, Culicidae do semiárido da Paraíba

    Directory of Open Access Journals (Sweden)

    Francisco P. de Castro Jr.

    2013-06-01

    Full Text Available O presente trabalho teve como objetivo comparar os ciclos de vida entre amostras de populações de Aedes aegypti (Linnaeus, 1762 coletadas em dez municípios localizados no semiárido paraibano. Os ciclos de vida foram estudados a uma temperatura de 26 ± 2ºC, umidade relativa de 60 ± 10% e fotofase de 12 horas. Diariamente foram avaliados os períodos de desenvolvimentos e as viabilidades das fases de ovo, larva e pupa, bem como a razão sexual, longevidade, tamanho e fecundidade dos adultos. Foi realizada uma análise de agrupamento, utilizando-se uma matriz de distância euclidiana através do método da média não-ponderada. As durações e viabilidades para as fases de ovo, larva e pupa apresentaram respectivamente, uma variação média de 3,7 a 4,7 dias e 82,8% a 97,7%, 9,1 a 10,8 dias e 91,2% a 99,2% e de 2,1 a 2,5 dias e 93,5% a 98,4%. O comprimento alar foi de 5,13 a 5,34 mm para as fêmeas e de 4,18 a 4,25 mm para os machos. A menor fecundidade (153,6 ovos/fêmea ocorreu na população de A. aegypti oriunda de Pedra Lavrada, enquanto que a maior fecundidade (310,6 ovos/fêmea foi constatada para A. aegypti de Campina Grande. A análise de agrupamento com base na similaridade dos dados biológicos revelou a formação de dois grandes grupos distintos, onde as populações de A. aegypti de Serra Branca e Cuité apresentam maior similaridade entre si. As diferenças de ciclos biológicos verificadas entre as populações de A. aegypti demonstra a capacidade dessa espécie de sofrer variações na sua biologia e se adaptar às diferentes condições ambientais, favorecendo a permanência deste inseto nessas áreas com aumento do risco de transmissão do vírus da dengue.

  20. Chemical Composition and Biological Activity of Essential Oils from Four Nepeta Species and Hybrids against Aedes aegypti (L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Abbas Ali

    2015-08-01

    Full Text Available Essential oils of four ornamental species and hybrids of Nepeta: N. racemosa Lam. hybrid ‘Select’, N. sibirica L., N. subsessilis Maxim, and N.×faassenii Bergmans ex Stearn ‘Dropmore were studied for their chemical composition, larvicidal and biting deterrent activity. Water-distilled essential oils from aerial parts of Nepeta species were analyzed by gas chromatography (GC-FID and gas chromatography mass spectrometry (GC-MS. Nepeta racemosa hybrid ‘Select’ and N. ×faassenii ‘Dropmore’ essential oils were rich in 1,8-cineole whereas N. sibirica and N. subsessilis essential oils mainly consisted of sesquiterpenes: (Z- b -farnesene, b -bisabolene, d -cadinene or b -caryophyllene, and caryophyllene oxide. Many Nepeta species essential oils are reported to be rich in nepetalactone isomers, but essential oils from these species contained either very low or no nepetalactone content. In biting deterrent bioassays, essential oils of these Nepeta species and hybrids at 100 µg/cm 2 showed activity similar to DEET at 25 nmol/cm 2 against Aedes aegypti, whereas this activity at the concentration of 10 µg/cm 2 was lower than DEET. All the essential oils showed weak larvicidal activity and mortalities were observed only at highest dose of 125 ppm against Ae. aegypti.

  1. Estimation of Aedes aegypti (Diptera: Culicidae population size and adult male survival in an urban area in Panama

    Directory of Open Access Journals (Sweden)

    Marco Neira

    2014-11-01

    Full Text Available Traditional mosquito control strategies rely heavily on the use of chemical insecticides. However, concerns about the efficiency of traditional control methods, environmental impact and emerging pesticide resistance have highlighted the necessity for developing innovative tools for mosquito control. Some novel strategies, including release of insects carrying a dominant lethal gene (RIDL®, rely on the sustained release of modified male mosquitoes and therefore benefit from a thorough understanding of the biology of the male of the species. In this report we present the results of a mark-release-recapture study aimed at: (i establishing the survival in the field of laboratory-reared, wild-type male Aedes aegypti and (b estimating the size of the local adult Ae. aegypti population. The study took place in Panama, a country where recent increases in the incidence and severity of dengue cases have prompted health authorities to evaluate alternative strategies for vector control. Results suggest a life expectancy of 2.3 days for released male mosquitoes (confidence interval: 1.78-2.86. Overall, the male mosquito population was estimated at 58 males/ha (range 12-81 males/ha, which can be extrapolated to an average of 0.64 pupae/person for the study area. The practical implications of these results are discussed.

  2. Synergistic actions of formamidine insecticides on the activity of pyrethroids and neonicotinoids against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Ahmed, M A I; Matsumura, F

    2012-11-01

    Formamidines are unique insecticides and acaricides that elicit multiple effects in controlling insects. Here, we tested two formamidines, amitraz, and chlordimeform, for their synergistic actions on type II pyrethroids and neonicotinoids to increase their larvicidal actions on the fourth instars of Aedes aegypti L. An organophosphate insecticide was used as a negative control. After 24 h, the synergism of formamidines was highest on imidacloprid, followed by two type II pyrethroids, deltamethrin and fenvalerate. After 48 h, the synergism of formamidines on imidacloprid decreased, remained unchanged on type II pyrethroids, and increased noticeably on two of the newer type neonicotinoids, dinotefuran and thiamethoxam. By 72 h, synergism of formamidines on dinotefuran reached the maximum, while that on imidacloprid was at a minimum. Both formamidines did not show synergistic effects on permethrin or fenitrothion. In all cases, the synergistic effects of amitraz on the two major classes of larvicides were greater than for chlordimeform. These results indicate that amitraz is a promising synergist that shows the potential to increase the efficacy of certain members of type II pyrethroids as well as neonicotinoids to control Ae. aegypti larvae.

  3. Insecticidal Activity of [Cu(H2NTA2].2H2O in Aedes aegypti Larvae (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Alessandra Ramos Lima

    2015-12-01

    Full Text Available The demand for new insecticides and alternative strategies for the population control of Aedes aegypti has stimulated research to obtain new compounds with broad biological activity. Accordingly, the dihydrogen nitrilotriacetate complex of copper (II dihydrate, [Cu(H2NTA2].2H2O, was synthesized by the stoichiometric reaction of nitrilotriacetic acid (H3NTA hydroxide with basic copper carbonate (II (Cu2(OH2CO3 and characterized by the spectroscopic techniques UV-Vis and FT-IR. The biological toxicity in A. aegypti was determined by bioassay using concentrations ranging from 90.0 mg L−1 to 897.4 mg L−1. The LC50 obtained was 146.11 mg L−1 [132.18–160.10] and the LT50 obtained at a concentration of 897.4 mg L−1 was 70.61 min [38.21–94.90]. The results showed that the complex obtained in this work is a potential metal-insecticide. DOI: http://dx.doi.org/10.17807/orbital.v7i4.735 

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

    Directory of Open Access Journals (Sweden)

    Rafael Maciel-de-Freitas

    2006-05-01

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

  5. Effects of larval crowding on development time, survival and weight at metamorphosis in Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Arnaldo MACIÁ

    2009-01-01

    Full Text Available Los efectos del hacinamiento larval sobre el tiempo de desarrollo, la supervivencia y el peso en la metamorfosis fueron estudiados en el mosquito del dengue, Aedes aegypti L., en el laboratorio. Se criaron cohortes de larvas en 7 densidades (4, 8, 16, 32, 64, 128 y 256 larvas/ recipiente de 175 ml mientras se mantuvo constante el volumen de agua y la calidad y cantidad de alimento, bajo fotoperíodo y temperatura controlados. Se usaron detritos naturales, principalmente hojas, obtenidos de contenedores colonizados naturalmente por A. aegypti como fuente de nutrientes para las larvas. En cada densidad se registraron el tiempo de desarrollo, la mortalidad, el peso en la metamorfosis y la biomasa total. El tiempo de desarrollo varió entre 4 y 23 días en los machos, y 5 a 24 días en hembras; fue más prolongado a la densidad de 64 (en las hembras y 128 (en los machos larvas por recipiente. En densidades altas la proporción de sexos favoreció los machos. Hubo un incremento en la mortalidad en densidades iguales o mayores que 0,4 larvas/ ml (0,32 larvas/cm2. Se detectó una relación inversa entre la densidad larval y el peso de las pupas. La biomasa por individuo alcanzó un valor asintótico de aproximadamente 1 mg/individuo en una densidad de 128 individuos/ recipiente (0,64 larvas/cm2. Las poblaciones de A. aegypti, cercanas a su extremo sur de distribución, serían sensibles al hacinamiento en pequeños contenedores de agua.

  6. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae population in California [version 3; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Anthony J. Cornel

    2016-08-01

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

  7. Surveillance, insecticide resistance and control of an invasive Aedes aegypti (Diptera: Culicidae population in California [version 2; referees: 2 approved

    Directory of Open Access Journals (Sweden)

    Anthony J. Cornel

    2016-03-01

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

  8. Rhamnolipids: solution against Aedes aegypti?

    OpenAIRE

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

    2015-01-01

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

  9. Effect of stalk and leaf extracts from Euphorbiaceae species on Aedes aegypti (Diptera, Culicidae larvae Efeito dos extratos de caule e folha de espécies de Euphorbiaceae sobre larvas de Aedes aegypti (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Maria Goretti Araújo de Lima

    2006-08-01

    Full Text Available The objective of this study was to evaluate the larvicidal activity of essential oil aqueous solutions (hydrolates obtained by steam distillation of stalks and leaves of Croton argyrophylloides, Croton nepetaefolius, Croton sonderianus and Croton zehntneri against Aedes aegypti larvae. Twenty-five larvae of third instar were placed in plastic beckers, containing the hydrolates (50 mL, in a four repetitions scheme. Water was used as control and the number of dead larvae was counted after 24 hours. The data obtained were submitted to Variance Analysis and Tukey test. Significant differences were observed among the hydrolates from different species and from different parts of each plant (p O objetivo deste trabalho foi avaliar a atividade larvicida dos hidrolatos obtidos por destilação à vapor de caule e folha das espécies de Croton argyrophylloides, Croton nepetaefolius, Croton sonderianus e Croton zehntneri contra Aedes aegypti. Em cada bioensaio foram utilizadas 25 larvas de 3º estádio juntamente com 50 mL de cada hidrolato, dispostos em recipientes plásticos, num esquema de quatro repetições, utilizando-se como controle a água e avaliando-se a mortalidade com 24 horas de tratamento. Os dados foram submetidos à análise de variância e ao teste de Tukey. Verificou-se que houve diferença significativa tanto em relação aos hidrolatos das diferentes espécies vegetais, quanto em relação às diferentes partes de cada planta (p < 0,001. Os hidrolatos referentes ao caule e folha de C. nepetaefolius e C. zehntneri causaram 100% de mortalidade das larvas e diferiram das demais espécies, exceto da folha do C. argyrophylloides que apresentou o mesmo resultado. Os compostos presentes em C. zehntneri e C. nepetaefolius são fenil propanóides mais solúveis em água que os monoterpenos e sesquiterpenos detectados em C. argyrophylloides e C. sonderianus. Esta pesquisa evidenciou que todas as espécies testadas possuem compostos com

  10. Impact of small variations in temperature and humidity on the reproductive activity and survival of Aedes aegypti (Diptera, Culicidae); Impacto de pequenas variacoes de temperatura e umidade na atividade reprodutiva e sobrevivencia de Aedes aegypti (Diptera, Culicidae)

    Energy Technology Data Exchange (ETDEWEB)

    Costa, Ethiene Arruda Pedrosa de Almeida; Santos, Eloina Maria de Mendonca; Correia, Juliana Cavalcanti; Albuquerque, Cleide Maria Ribeiro de, E-mail: cleide.ufpe@gmail.co [Universidade Federal de Pernambuco (UFPE), Recife, PE (Brazil). Centro de Ciencias Biologicas. Dept. de Zoologia

    2010-07-01

    In short space of time increase in temperature and rainfall can affect vector populations and, consequently, the diseases for them transmitted. The present study analyzed the effect of small temperature and humidity variations on the fecundity, fertility and survival of Aedes aegypti. These parameters were analyzed using individual females at temperatures ranging from 23 to 27 deg C (mean 25 deg C); 28 to 32 deg C (mean 30 deg C) and 33 to 37 deg C (mean 35 deg C) associated to 60 +- 8% and 80 +- 6% relative humidity. Females responded to an increase in temperature by reducing egg production, oviposition time and changing oviposition patterns. At 25 deg C and 80% relative humidity, females survived two-fold more and produced 40% more eggs when compared to those kept at 35 deg C and 80% relative humidity. However, in 45% of females kept at 35 deg C and 60% relative humidity oviposition was inhibited and only 15% females laid more than 100 eggs, suggesting that the intensity of the temperature effect was influenced by humidity. Gradual reductions in egg fertility at 60% relative humidity were observed with the increase in temperature, although such effect was not found in the 80% relative humidity at 25 deg C and 30 deg C. These results suggest that the reduction in population densities recorded in tropical areas during seasons when temperatures reach over 35 deg C is likely to be strongly influenced by temperature and humidity, with a negative effect on several aspects of mosquito biology. (author)

  11. Mukia maderaspatana (Cucurbitaceae) extract-mediated synthesis of silver nanoparticles to control Culex quinquefasciatus and Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Chitra, Govindaraj; Balasubramani, Govindasamy; Ramkumar, Rajendiran; Sowmiya, Rajamani; Perumal, Pachiappan

    2015-04-01

    Mosquitoes and mosquito-borne diseases are prone to raise health and economic impacts. Synthetic insecticide-based interventions are indeed in situations of epidemic outbreak and sudden increases of adult mosquitoes. Nanoparticles are being used in many commercial applications and were found that aqueous silver ions can be reduced by an aqueous extract of plant parts to generate extremely stable silver nanoparticles in water. Based on this, silver nanoparticles (SNPs) were synthesized using leaf aqueous extract (LAE) of Mukia maderaspatana. Further, the synthesized SNPs were characterized by UV-visible spectrum, which indicated a strong plasmon resonance at 427 nm. X-ray diffraction (XRD) analysis revealed the average crystalline size of the synthesized SNPs was approximately 64 nm by Debye-Scherrer formulae. Fourier transform infrared (FTIR) spectroscopy analysis revealed the presence of different functional groups like amines, halides, alkanes, alkynes, amides, and esters with respective stretches, which are responsible for the bio-reduction of silver ions. Field emission scanning electron microscopy (FESEM) depicted the spherical morphology of SNPs with size range of 13-34 nm. The larvicidal activity of LAE and SNPs exhibited an effective mortality to Aedes aegypti and Culex quinquefasciatus. The lethal concentration (LC50; LC90) of LAE and SNPs were found to be 0.506; 1.082, 0.392; 0.870 ppm and 0.211; 0.703, 0.094; 0.482 ppm, respectively on A. aegypti and C. quinquefasciatus. Thus, the synthesized SNPs have shown preponderant larvicidal activity, but further studies are needed to formulate the potential larvicidal agents.

  12. A new strategy for Aedes aegypti (Diptera: Culicidae) control with community participation using a new fumigant formulation.

    Science.gov (United States)

    Harburguer, Laura; Beltrán, Gaston; Goldberg, Lucila; Goldberg, Laura; Zerba, Eduardo; Licastro, Susana; Masuh, Héctor

    2011-05-01

    Dengue and dengue hemorrhagic fever are mosquito-borne viral diseases that coincide with the distribution of Aedes aegypti (L.), the primary vector in the tropical and semitropical world. With no available vaccine, controlling the dengue vector is essential to avoid epidemics. This study evaluates the efficacy of a new smoke-generating formulation containing pyriproxyfen and permethrin in Puerto Libertad, Misiones, Argentina. A fumigant tablet (FT) was applied inside the houses by the community members and compared with a professional application. A treatment combining the application of fumigant tablets indoors and ultralow volume fumigation outdoors was also assessed. The community perceptions and practices about dengue disease and the acceptance of this new nonprofessional FT were evaluated through surveys. Results show >90% adult emergence inhibition and 100% adult mortality with these treatments. More than 80% of the residents applied the FT and preferred participating in a vector control program by using a nonprofessional mosquito control tool, instead of attending meetings and workshops promoting cultural changes.

  13. Evaluation of a peridomestic mosquito trap for integration into an Aedes aegypti (Diptera: Culicidae) push-pull control strategy.

    Science.gov (United States)

    Salazar, Ferdinand V; Achee, Nicole L; Grieco, John P; Prabaripai, Atchariya; Eisen, Lars; Shah, Pankhil; Chareonviriyaphap, Theeraphap

    2012-06-01

    We determined the feasibility of using the BG-Sentinel™ mosquito trap (BGS) as the pull component in a push-pull strategy to reduce indoor biting by Aedes aegypti. This included evaluating varying numbers of traps (1-4) and mosquito release numbers (10, 25, 50, 100, 150, 200, and 250) on recapture rates under screen house conditions. Based on these variations in trap and mosquito numbers, release intervals were rotated through a completely randomized design with environmental factors (temperature, relative humidity, and light intensity) and monitored throughout each experiment. Data from four sampling time points (05:30, 09:30, 13:30, and 17:30) indicate a recapture range among treatments of 66-98%. Furthermore, 2-3 traps were as effective in recapturing mosquitoes as 4 traps for all mosquito release numbers. Time trends indicate Day 1 (the day the mosquitoes were released) as the "impact period" for recapture with peak numbers of marked mosquitoes collected at 09:30 or 4 h post-release. Information from this study will be used to guide the configuration of the BGS trap component of a push-pull vector control strategy currently in the proof-of-concept stage of development in Thailand and Peru.

  14. 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

  15. Comparison of Field and Laboratory-Based Tests for Behavioral Response of Aedes aegypti (Diptera: Culicidae) to Repellents.

    Science.gov (United States)

    Sathantriphop, Sunaiyana; Kongmee, Monthathip; Tainchum, Krajana; Suwansirisilp, Kornwika; Sanguanpong, Unchalee; Bangs, Michael J; Chareonviriyaphap, Theeraphap

    2015-12-01

    The repellent and irritant effects of three essential oils-clove, hairy basil, and sweet basil-were compared using an excito-repellency test system against an insecticide-resistant strain of Aedes aegypti (L.) females from Pu Teuy, Kanchanaburi Province. DEET was used as the comparison standard compound. Tests were conducted under field and controlled laboratory conditions. The most marked repellent effect (spatial noncontact assay) among the three test essential oils was exhibited by sweet basil, Ocimum basilicum L. (53.8% escaped mosquitoes in 30-min exposure period) under laboratory conditions while hairy basil, Ocimum americanum L. and clove, Syzygium aromaticum (L.) Merill et. L.M. Perry from laboratory tests and sweet basil from field tests were the least effective as repellents (0-14%). In contrast, the contact assays measuring combined irritancy (excitation) and repellency effects found the best contact irritant response to hairy basil and DEET in field tests, whereas all others in laboratory and field were relatively ineffective in stimulating mosquitoes to move out the test chambers (0-5.5%). All three essential oils demonstrated significant differences in behavioral responses between field and laboratory conditions, whereas there was no significant difference in contact and noncontact assays for DEET between the two test conditions (P > 0.05). PMID:26470388

  16. Efectos de la competencia larval en los mosquitos de contenedores artificiales, Aedes aegypti y Culex pipiens (Diptera: Culicidae en condiciones semi-controladas

    Directory of Open Access Journals (Sweden)

    Analía FRANCIA

    2011-01-01

    Full Text Available Las larvas de los mosquitos Aedes aegypti (Linneo y Culex pipiens Linneo pueden criar conjuntamente en pequeños contenedores artificiales de agua, se genera así una competencia interespecífica y/o intraespecífica. El objetivo de este trabajo fue comparar la magnitud relativa de la competencia intra e interespecífica en A. aegypti y C. pipiens, generada durante el desarrollo larval en contenedores artificiales. Las variables medidas como respuesta fueron la supervivencia y el tiempo de desarrollo larval, y la biomasa total producida en estado de pupa. Se criaron larvas de ambos mosquitos en neumáticos de automóvil con agua declorinada y hojarasca. Se introdujeron larvas recién eclosionadas de acuerdo a la densidad (δ estimada según un censo previo de A. aegypti y C. pipiens. Se realizaron los siguientes tratamientos agregando larvas de: (1 A. aegypti hasta alcanzar δ A. aegypti determinada según el censo previo, (2 C. pipiens hasta δ C. pipiens del censo previo, (3 A. aegypti hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo, (4 C. pipiens hasta alcanzar la suma de δ A. aegypti y δ C. pipiens del censo previo y (5 A. aegypti y C. pipiens hasta δ A. aegypti y δ C. pipiens del censo previo. Las tres variables medidas fueron afectadas por los tratamientos, excepto la supervivencia y la biomasa producida por C. pipiens. Aedes aegypti fue más alterada por la competencia intraespecífica que por la competencia interespecífica. En C. pipiens, la competencia interespecífica superó en sus efectos a la competencia intraespecífica. Existió asimetría competitiva, ya que C. pipiens fue más afectada por A. aegypti que lo contrario.

  17. Evaluation of the Larvicidal Efficacy of Five Indigenous Weeds against an Indian Strain of Dengue Vector, Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Aarti Sharma; Sarita Kumar; Pushplata Tripathi

    2016-01-01

    Background and Objectives. Aedes aegypti, dengue fever mosquito, is primarily associated with the transmission of dengue and chikungunya in tropical and subtropical regions of the world. The present investigations were carried out to assess the larvicidal efficiency of five indigenous weeds against Ae. aegypti. Methods. The 1,000 ppm hexane and ethanol extracts prepared from the leaves and stem of five plants (Achyranthes aspera, Cassia occidentalis, Catharanthus roseus, Lantana camara, and X...

  18. Impact of Argemone mexicana extracts on the cidal, morphological, and behavioral response of dengue vector, Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Warikoo, Radhika; Kumar, Sarita

    2013-10-01

    The larvicidal, behavioral, and morphological response of dengue vector, Aedes aegypti treated with deleterious weed, Argemone mexicana, was explored. The 1,000 ppm extracts of A. mexicana leaf, stem, and roots prepared in five different solvents (petroleum ether, hexane, benzene, acetone, and ethanol) were screened for their larvicidal activity against dengue vector establishing the efficacy of petroleum ether and hexane extracts. Other extracts, unable to give 100% mortality, were considered ineffective and discarded from further study. Larvicidal bioassay conducted with selected extracts confirmed the higher efficacy of hexane extracts exhibiting 1.1- to 1.8-fold more potential than the petroleum ether extracts. The results further revealed 1.6- to 2.4-fold higher efficacy of root extracts than those prepared from the leaves and stem of A. mexicana. The hexane root extract of A. mexicana was found to be the most effective larvicide with LC50 value of 91.331 ppm after 24 h of exposure causing 1.8 and 2.4 fold more toxicity as compared to the hexane leaf and stem extracts, respectively. Prolonged exposure of the larvae to the extracts resulted in increased toxicity potential of the extracts. Observations of the treated larvae revealed excitation, violent vertical, and horizontal movements with aggressive anal biting behavior suggesting effect of extracts on their neuromuscular system. Morphological studies of the treated larvae revealed the demelanization of cuticle and shrinkage of internal cuticle of anal papillae indicating the anal papillae as the probable action sites of the A. mexicana extracts. The potential of A. mexicana as new larvicides against dengue vector are being explored.

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

    Directory of Open Access Journals (Sweden)

    Waldemir Pereira Lima

    2009-12-01

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

  20. 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.

  1. 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)

  2. Thiosemicarbazones as Aedes aegypti larvicidal.

    Science.gov (United States)

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

    2015-07-15

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

  3. Thiosemicarbazones as Aedes aegypti larvicidal.

    Science.gov (United States)

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

    2015-07-15

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

  4. Insecticidal and genotoxic potential of two semi-synthetic derivatives of dillapiole for the control of Aedes (Stegomyia) aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Domingos, Pedro Rauel Cândido; da Silva Pinto, Ana Cristina; dos Santos, Joselita Maria Mendes; Rafael, Míriam Silva

    2014-09-15

    The effects of two semi-synthetic dillapiole derivatives, ethyl-ether dillapiole and n-butyl ether dillapiole, on eggs and larvae of Aedes aegypti were studied in view of the need for expansion and renovation of strategic action to control this mosquito - the vector of Dengue virus -, which currently shows a high resistance to chemical insecticides. Eggs and third-instar larvae of A. aegypti that had been exposed to different concentrations of these two compounds showed toxicity and susceptibility, with 100% mortality. Classical cytogenetic assays showed genotoxicity caused by the two compounds in A. aegypti from the cumulative effect of nuclear abnormalities, indicating that these derivatives may be potential alternatives to control A. aegypti.

  5. Spatial analysis of wing geometry in dengue vector mosquito, Aedes aegypti (L. (Diptera: Culicidae, populations in Metropolitan Manila, Philippines

    Directory of Open Access Journals (Sweden)

    Thaddeus M Carvajal

    2016-01-01

    Interpretation & conclusion: The newly modified wing preparation procedure was able to capture a complete coverage of the wings of Ae. aegypti, thus providing a stronger separation power for very close populations in an urban area. It is also noteworthy that the results of IBD and SA supported the findings of GM in the population structuring of male and female Ae. aegypti. The outcome of the study increases our understanding of the vector, which would be useful in developing effective control strategies.

  6. 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...

  7. Variation in Aedes aegypti(Diptera: Culicidae) container productivity in a slum and a suburban district of Rio de Janeiro during dry and wet seasons

    OpenAIRE

    Rafael Maciel-de-Freitas; William A Marques; Roberto C Peres; Sérgio P Cunha; Ricardo Lourenço-de-Oliveira

    2007-01-01

    Seasonal variation in container productivity and infestation levels by Aedes aegypti were evaluated in two areas with distinct levels of urbanization degrees in Rio de Janeiro, a slum and a suburban neighborhood. The four most productive containers can generate up to 90% of total pupae. Large and open-mouthed containers, such as water tanks and metal drums, located outdoors were the most productive in both areas, with up to 47.49% of total Ae. aegypti pupae collected in the shaded sites in th...

  8. OFF! Clip-on Repellent Device With Metofluthrin Tested on Aedes aegypti (Diptera: Culicidae) for Mortality at Different Time Intervals and Distances.

    Science.gov (United States)

    Bibbs, Christopher S; Xue, Rui-De

    2016-03-01

    The OFF! Clip-on mosquito-repellent device was tested outdoors against Aedes aegypti (L.). A single treatment device was used against batches of caged adult, nonblood fed Ae. aegypti at multiple locations 0.3m from treatment center. Another set of cages was stationed 0.6m from treatment. A final set of cages was placed 0.9m away. Trials ran for durations of 5, 15, 30, and 60 min. Initial knockdown and mortality after 24 h was recorded. The devices had effective knockdown and mortality. This was not sustained at distances greater than 0.3m from the device. PMID:26668103

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

    Directory of Open Access Journals (Sweden)

    R Muthusamy

    2015-01-01

    Interpretation & conclusion: The high activity of esterase, mixed-function oxidase (MFO and ace-1 mutation frequency were closely associated with temephos resistance. Early detection of resistance alleles in natural vector population could be useful for the successful implementation of insecticide resistance management strategies. The results of this study provide baseline data on temephos resistance in Ae. aegypti populations.

  10. 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

  11. 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...

  12. The combination of the entomopathogenic fungus Metarhizium anisopliae with the insecticide Imidacloprid increases virulence against the dengue vector Aedes aegypti (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Samuels Richard I

    2011-01-01

    Full Text Available Abstract Background Dengue fever transmitted by the mosquito Aedes aegypti, is one of the most rapidly spreading insect borne diseases, stimulating the search for alternatives to current control measures. The dengue vector A. aegypti has received less attention than anophelene species, although more than 2.5 billion people are at risk of infection worldwide. Entomopathogenic fungi are emerging as potential candidates for the control of mosquitoes. Here we continue our studies on the pathogenicity of the entomopathogenic fungus Metarhizium anisopliae against adult A. aegypti females. With the aim of further reducing mean survival times of A. aegypti exposed to fungus impregnated surfaces, a sub-lethal concentration of the neonicotinoid insecticide Imidacloprid (IMI was added to fungal suspensions. Results A sub-lethal concentration of IMI that did not significantly alter the daily survival rates or mean survival percentages of mosquitoes was identified to be 0.1 ppm. This sub-lethal concentration was combined with M. anisopliae conidia (1 × 109 conidia mL-1. Both the combined treatment and the conidia alone were able to reduce the survival of A. aegypti compared with untreated or IMI treated mosquitoes. Importantly, mosquito survival following exposure to the combined treatment for 6 and 12 hrs was significantly reduced when compared with mosquitoes exposed to conidia alone. Conclusions This is the first time that a combination of an insecticide and an entomopathogenic fungus has been tested against A. aegypti. Firstly, the study showed the potential of IMI as an alternative to the currently employed pyrethroid adulticides. Secondly, as an alternative to applications of high concentrations of chemical insecticides, we suggest that adult A. aegypti could be controlled by surface application of entomopathogenic fungi and that the efficiency of these fungi could be increased by combining the fungi with ultra-low concentrations of insecticides

  13. 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

  14. Comparison of Aedes aegypti (Diptera: Culicidae) resting behavior on two fabric types under consideration for insecticide treatment in a push-pull strategy.

    Science.gov (United States)

    Tainchum, Krajana; Polsomboon, Suppaluck; Grieco, John P; Suwonkerd, Wannapa; Prabaripai, Atchariya; Sungvornyothin, Sungsit; Chareonviriyaphap, Theeraphap; Achee, Nicole L

    2013-01-01

    Aedes aegypti (L.), the primary vector of dengue and dengue hemorrhagic fever, breeds and rests predominately inside human dwellings. With no current vaccine available, vector control remains the mainstay for dengue management and novel approaches continue to be needed to reduce virus transmission. This requires a full understanding of Ae. aegypti ecology to design effective strategies. One novel approach is the use of contact irritants at target resting sites inside homes to make the surface unacceptable and cause vectors to escape before biting. The objective of the current study was to observe indoor resting behavior patterns of female Ae. aegypti within experimental huts in response to two fabrics under consideration for insecticide treatment: cotton and polyester. Results indicate that fabric type, coverage ratio of dark to light fabric and placement configuration (vertical vs. horizontal) all influenced the resting pattern of mosquito cohorts. Findings from this study will guide evaluations of a push-pull strategy designed to exploit contact irritant behaviors and drive Ae. aegypti out of homes prefeeding.

  15. Altered behavioral responses of Sindbis virus-infected Aedes aegypti (Diptera: Culicidae) to DEET and non-DEET based insect repellents.

    Science.gov (United States)

    Qualls, Whitney A; Day, Jonathan F; Xue, Rui-de; Bowers, Doria F

    2012-06-01

    Changes in the time to first bite (TFB) and the bloodfeeding behavior of adult female Aedes aegypti (L.) mosquitoes following dissemination of Sindbis virus (SINV) were observed after exposure to repellents with the active ingredients (AI) DEET, picaridin, 2-undecanone (2-U), and oil of lemon eucalyptus. Dissemination of SINV significantly decreased (PTFB of DEET (15%) and picaridin (15%) by 46% and 37%, respectively. Significant (PTFB and time to complete the four bloodfeeding stages will lessen the prey-status, and enhance both the chances of mosquito survival and arbovirus transmission. PMID:22289669

  16. Oviposition strategies adopted by gravid Aedes aegypti (L.) (Diptera: Culicidae) as detected by ovitraps in Trinidad, West Indies (2002-2006).

    Science.gov (United States)

    Chadee, D D

    2009-09-01

    Aedes aegypti oviposition strategies were studied weekly over a period of 5 years (2002-2006) in Curepe, Trinidad using modified ovitraps. From a total of 23,293 ovitraps collected, 10,156 were collected in the months of the dry season, with 3041 positive (30%) containing 99,577 Ae. aegypti eggs. In contrast, during the wet season from 13,137 ovitraps collected, 10,652 were positive (81.9%), containing 192,209 Ae. aegypti eggs. When, the number of eggs collected and the number of positive ovitraps were divided into different egg number categories, 91, significantly more eggs (G=89.6; d.f.=4; P91 eggs. The patterns of oviposition displayed by Ae. aegypti during the early, mid and late wet and dry seasons showed a significant (F=102.8; d.f.=5; Pwet season, significant (F=209.8; d.f.=5; P91 egg category. These results suggest that the oviposition strategies adopted depend on numerous factors including the physical state of the oviposition site, the presence of eggs from conspecific females, whether the same or different individuals and the number or clutch size already present on the oviposition site. Therefore vector control workers should employ source reduction strategies to remove the small containers which may harbour 1-30 eggs and treat the larger permanent containers like water drums which may contain >60 eggs and may be the sites of superoviposition in nature. These combined strategies can effectively control the vector populations and reduce dengue transmission in Ae. aegypti infested countries. PMID:19481998

  17. 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

  18. Variation in Aedes aegypti(Diptera: Culicidae container productivity in a slum and a suburban district of Rio de Janeiro during dry and wet seasons

    Directory of Open Access Journals (Sweden)

    Rafael Maciel-de-Freitas

    2007-06-01

    Full Text Available Seasonal variation in container productivity and infestation levels by Aedes aegypti were evaluated in two areas with distinct levels of urbanization degrees in Rio de Janeiro, a slum and a suburban neighborhood. The four most productive containers can generate up to 90% of total pupae. Large and open-mouthed containers, such as water tanks and metal drums, located outdoors were the most productive in both areas, with up to 47.49% of total Ae. aegypti pupae collected in the shaded sites in the suburban area. Water-tanks were identified as key containers in both areas during both the dry and rainy seasons. Container productivity varied according to seasons and urbanization degree. However, the mean number of pupae per house was higher in the suburban area, but not varied between seasons within each area (P > 0.05. High infestation indexes were observed for both localities, with a house index of 20.5-21.14 in the suburban and of 9.56-11.22 in the urban area. This report gives potential support to a more focused and cost-effective Ae. aegypti control in Rio de Janeiro.

  19. Variation in Aedes aegypti (Diptera: Culicidae) container productivity in a slum and a suburban district of Rio de Janeiro during dry and wet seasons.

    Science.gov (United States)

    Maciel-de-Freitas, Rafael; Marques, William A; Peres, Roberto C; Cunha, Sérgio P; de Oliveira, Ricardo Lourenço

    2007-06-01

    Seasonal variation in container productivity and infestation levels by Aedes aegypti were evaluated in two areas with distinct levels of urbanization degrees in Rio de Janeiro, a slum and a suburban neighborhood. The four most productive containers can generate up to 90% of total pupae. Large and open-mouthed containers, such as water tanks and metal drums, located outdoors were the most productive in both areas, with up to 47.49% of total Ae. aegypti pupae collected in the shaded sites in the suburban area. Water-tanks were identified as key containers in both areas during both the dry and rainy seasons. Container productivity varied according to seasons and urbanization degree. However, the mean number of pupae per house was higher in the suburban area, but not varied between seasons within each area (P > 0.05). High infestation indexes were observed for both localities, with a house index of 20.5-21.14 in the suburban and of 9.56-11.22 in the urban area. This report gives potential support to a more focused and cost-effective Ae. aegypti control in Rio de Janeiro. PMID:17612770

  20. 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.

  1. 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.

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

    Science.gov (United States)

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

    2016-01-01

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

  3. 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

  4. The role of octopamine receptor agonists in the synergistic toxicity of certain insect growth regulators (IGRs) in controlling Dengue vector Aedes aegypti (Diptera: Culicidae) mosquito.

    Science.gov (United States)

    Ahmed, Mohamed Ahmed Ibrahim; Vogel, Christoph Franz Adam

    2016-03-01

    The synergistic action of octopamine receptor agonists (OR agonists) on many insecticide classes (e.g., organophosphorus, pyrethroids, and neonicotinoids) on Aedes aegypti L. has been reported recently. An investigation of OR agonist's effect on insect growth regulators (IGRs) was undertaken to provide a better understanding of the mechanism of action. Based on the IGR bioassay, pyriproxyfen was the most potent IGR insecticide tested (EC50=0.0019ng/ml). However, the lethal toxicity results indicate that diafenthiuron was the most potent insecticide (LC50=56ng/cm(2)) on A. aegypti adults after 24h of exposure. The same trend was true after 48 and 72h of exposure. Further, the synergistic effects of OR agonists plus amitraz (AMZ) or chlordimeform (CDM) was significant on adults. Among the tested synergists, AMZ increased the potency of the selected IGRs on adults the greatest. As results, OR agonists were largely synergistic with the selected IGRs. OR agonists enhanced the lethal toxicity of IGRs, which is a valuable new tool in the field of A. aegypti control. However, further field experiments need to be done to understand the unique potential role of OR agonists and their synergistic action on IGRs.

  5. Evaluation of the Larvicidal Efficacy of Five Indigenous Weeds against an Indian Strain of Dengue Vector, Aedes aegypti L. (Diptera: Culicidae).

    Science.gov (United States)

    Sharma, Aarti; Kumar, Sarita; Tripathi, Pushplata

    2016-01-01

    Background and Objectives. Aedes aegypti, dengue fever mosquito, is primarily associated with the transmission of dengue and chikungunya in tropical and subtropical regions of the world. The present investigations were carried out to assess the larvicidal efficiency of five indigenous weeds against Ae. aegypti. Methods. The 1,000 ppm hexane and ethanol extracts prepared from the leaves and stem of five plants (Achyranthes aspera, Cassia occidentalis, Catharanthus roseus, Lantana camara, and Xanthium strumarium) were screened for their larvicidal activity against early fourth instars of dengue vector. The extracts which could cause 80-100% mortality were further investigated for their efficacy. Results. The preliminary screening established the efficacy of hexane extracts as compared to the ethanol extracts. Further investigations revealed the highest larvicidal potential of A. aspera extracts exhibiting LC50 value of 82.555 ppm and 68.133 ppm, respectively. Further, their leaf extracts showed 5-85.9% higher larvicidal activity and stem extracts exhibited 0.23- to 0.85-fold more efficiency than the other four extracts. Conclusion. The present investigations suggest the possible use of A. aspera as an ideal ecofriendly, larvicidal agent for the control of dengue vector, Ae. aegypti. Future studies are, however, required to explore and identify the bioactive component involved and its mode of action. PMID:26941996

  6. Evaluation of the Larvicidal Efficacy of Five Indigenous Weeds against an Indian Strain of Dengue Vector, Aedes aegypti L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Aarti Sharma

    2016-01-01

    Full Text Available Background and Objectives. Aedes aegypti, dengue fever mosquito, is primarily associated with the transmission of dengue and chikungunya in tropical and subtropical regions of the world. The present investigations were carried out to assess the larvicidal efficiency of five indigenous weeds against Ae. aegypti. Methods. The 1,000 ppm hexane and ethanol extracts prepared from the leaves and stem of five plants (Achyranthes aspera, Cassia occidentalis, Catharanthus roseus, Lantana camara, and Xanthium strumarium were screened for their larvicidal activity against early fourth instars of dengue vector. The extracts which could cause 80–100% mortality were further investigated for their efficacy. Results. The preliminary screening established the efficacy of hexane extracts as compared to the ethanol extracts. Further investigations revealed the highest larvicidal potential of A. aspera extracts exhibiting LC50 value of 82.555 ppm and 68.133 ppm, respectively. Further, their leaf extracts showed 5–85.9% higher larvicidal activity and stem extracts exhibited 0.23- to 0.85-fold more efficiency than the other four extracts. Conclusion. The present investigations suggest the possible use of A. aspera as an ideal ecofriendly, larvicidal agent for the control of dengue vector, Ae. aegypti. Future studies are, however, required to explore and identify the bioactive component involved and its mode of action.

  7. 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

  8. Physiological and biochemical effects of botanical extract from Piper nigrum Linn (Piperaceae) against the dengue vector Aedes aegypti Liston (Diptera: Culicidae).

    Science.gov (United States)

    Lija-Escaline, Jalasteen; Senthil-Nathan, Sengottayan; Thanigaivel, Annamalai; Pradeepa, Venkatraman; Vasantha-Srinivasan, Prabhakaran; Ponsankar, Athirstam; Edwin, Edward Sam; Selin-Rani, Selvaraj; Abdel-Megeed, Ahmed

    2015-11-01

    The leaves of Piper nigrum L. (Piperaceae) were evaluated for chemical constituents and mosquito larvicidal activity against the larvae of Aedes aegypti. GC and GC-MS analyses revealed that the crude extracts contain 16 compounds. Thymol (20.77%) and ç-elemene (10.42%) were identified as the major constituents followed by cyclohexene, 4-ethenyl-4-methyl-3-(1-methylethenyl)-1-(1 methylethyl)-, (3R-trans) (7.58%), 4,6-octadienoic acid, 2-acetyl-2-methyl-, ethyl ester (6.98), 2(3H)-furanone, 3,4-bis(1,3-benzodioxol-5-ylmethyl) dihydro-, (3R-trans) (6.95%), 1-naphthalenol, 1,2,3,4,4a,7,8,8a-octahydro-1,6-dimethyl-4-(1-methylethyl)-, [1R-(1à,4á,4aá,8aá)]-(Cedreanol) (5.30%), trans-2-undecen-1-ol (4.48%), phytol (4.22%), 1,6-cyclodecadiene, 1-methyl-5-methylene-8-(1-methylethyl)-,[s-(E,E)] (3.78%) and 2,6-dimethyl-3,5,7-octatriene-2-ol, Z,Z (2.39%). Larval mortality was observed after 3 h of exposure period. The crude extract showed remarkable larvicidal activity against Ae. aegypti (LC50 = 34.97). The larvae of Ae. aegypti exposed to the P. nigrum, significantly reduced the activities of α- and β-carboxylesterases and superdioxide. Further, P. nigrum extract was severely affecting the mosquito gut cellular organelles. Based on the results, the chemical constituents of crude extracts of P. nigrum can be considered as a new source of larvicide for the control of Ae. aegypti.

  9. Physiological and biochemical effects of botanical extract from Piper nigrum Linn (Piperaceae) against the dengue vector Aedes aegypti Liston (Diptera: Culicidae).

    Science.gov (United States)

    Lija-Escaline, Jalasteen; Senthil-Nathan, Sengottayan; Thanigaivel, Annamalai; Pradeepa, Venkatraman; Vasantha-Srinivasan, Prabhakaran; Ponsankar, Athirstam; Edwin, Edward Sam; Selin-Rani, Selvaraj; Abdel-Megeed, Ahmed

    2015-11-01

    The leaves of Piper nigrum L. (Piperaceae) were evaluated for chemical constituents and mosquito larvicidal activity against the larvae of Aedes aegypti. GC and GC-MS analyses revealed that the crude extracts contain 16 compounds. Thymol (20.77%) and ç-elemene (10.42%) were identified as the major constituents followed by cyclohexene, 4-ethenyl-4-methyl-3-(1-methylethenyl)-1-(1 methylethyl)-, (3R-trans) (7.58%), 4,6-octadienoic acid, 2-acetyl-2-methyl-, ethyl ester (6.98), 2(3H)-furanone, 3,4-bis(1,3-benzodioxol-5-ylmethyl) dihydro-, (3R-trans) (6.95%), 1-naphthalenol, 1,2,3,4,4a,7,8,8a-octahydro-1,6-dimethyl-4-(1-methylethyl)-, [1R-(1à,4á,4aá,8aá)]-(Cedreanol) (5.30%), trans-2-undecen-1-ol (4.48%), phytol (4.22%), 1,6-cyclodecadiene, 1-methyl-5-methylene-8-(1-methylethyl)-,[s-(E,E)] (3.78%) and 2,6-dimethyl-3,5,7-octatriene-2-ol, Z,Z (2.39%). Larval mortality was observed after 3 h of exposure period. The crude extract showed remarkable larvicidal activity against Ae. aegypti (LC50 = 34.97). The larvae of Ae. aegypti exposed to the P. nigrum, significantly reduced the activities of α- and β-carboxylesterases and superdioxide. Further, P. nigrum extract was severely affecting the mosquito gut cellular organelles. Based on the results, the chemical constituents of crude extracts of P. nigrum can be considered as a new source of larvicide for the control of Ae. aegypti. PMID:26277727

  10. Spatio-temporal distribution of Aedes aegypti (Diptera: Culicidae mitochondrial lineages in cities with distinct dengue incidence rates suggests complex population dynamics of the dengue vector in Colombia.

    Directory of Open Access Journals (Sweden)

    Jeiczon Jaimes-Dueñez

    2015-04-01

    Full Text Available Aedes aegypti is the primary vector of the four serotypes of dengue virus (DENV1-4, Chikungunya and yellow fever virus to humans. Previous population genetic studies have revealed a particular genetic structure among the vector populations in the Americas that suggests differences in the ability to transmit DENV. In Colombia, despite its high epidemiologic importance, the genetic population structure and the phylogeographic depiction of Ae. aegypti, as well as its relationship with the epidemiologic landscapes in cities with heterogeneous incidence levels, remains unknown. We conducted a spatiotemporal analysis with the aim of determining the genetic structure and phylogeography of Colombian populations of Ae. aegypti among cities with different eco-epidemiologic characteristics with regard to DENV.Mitochondrial cytochrome oxidase C subunit 1 (COI--NADH dehydrogenase subunit 4 (ND4 genes were sequenced and analyzed from 341 adult mosquitoes collected during 2012 and 2013 in the Colombian cities of Bello, Riohacha and Villavicencio, which exhibit low, medium and high levels of incidence of DENV, respectively. The results demonstrated a low genetic differentiation over time and a high genetic structure between the cities due to changes in the frequency of two highly supported genetic groups. The phylogeographic analyses indicated that one group (associated with West African populations was found in all the cities throughout the sampling while the second group (associated with East African populations was found in all the samples from Bello and in only one sampling from Riohacha. Environmental factors such as the use of chemical insecticides showed a significant correlation with decreasing genetic diversity, indicating that environmental factors affect the population structure of Ae. aegypti across time and space in these cities.Our results suggest that two Ae. aegypti lineages are present in Colombia; one that is widespread and related to a West

  11. Aedes aegypti resistance to temephos in Argentina

    OpenAIRE

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

    2008-01-01

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

  12. 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...

  13. INSECTICIDE RESISTANCE AND EFFECT OF PIPERONYL BUTOXIDE AS A SYNERGIST IN THREE STRAINS OF Aedes aegypti (Linn. (Diptera: Culicidae AGAINST INSECTICIDES PERMETHRIN, CYPERMETHRIN, AND D-ALLETHRIN

    Directory of Open Access Journals (Sweden)

    Sita Astari

    2012-09-01

    Full Text Available Tiga strain nyamuk Aedes aegypti yang dipelihara di laboratorium dan dikoleksi dari lapangan diuji menggunakan tiga jenis insektisida dari golongan piretroid (permetrin, cypermetrin, dan d-alletrin dengan metode bottle bioassay untuk mengetahui tingkatan dan mekanisme dari resistensi yang terjadi terhadap insektisida piretroid. Hasil penelitian menunjukkan bahwa ketiga strain yang diuji kemungkinan telah resisten terhadap ketiga insektisida tersebut, termasuk strain-strain yang telah dipelihara selama beberapa generasi di laboratorium, yang diindikasikan dengan nilai LT90 yang tinggi. Hasil ini mengindikasikan bahwa terdapat aktivitas MFO (Mixed-Function Oxidase pada ketiga strain yang diuji, di mana mekanisme tersebut mungkin berperan dalam menimbulkan resistensi pada ketiga strain, meskipun diduga terdapat mekanisme lain yang juga ikut terlibat.

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

    Directory of Open Access Journals (Sweden)

    Sarita eKumar

    2012-04-01

    Full Text Available 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 non target organisms too. In view of this, fifteen plants were collected from local areas in New Delhi, India. Different parts of these plants were separated, dried, mechanically grinded and sieved to get fine powder. The 200 g of each part was soaked in 1000 mL of different solvents separately and the crude extracts, thus formed, were concentrated using a vacuum evaporator at 45ºC under low pressure. Each extract was screened to explore its potential as a mosquito larvicidal agent against early fourth instars of dengue vector, Aedes aegypti using WHO protocol. The preliminary screening showed that only ten plants possessed larvicidal potential as they could result in 100% mortality at 1000 ppm. Further evaluation of the potential larvicidal extracts established the hexane leaf extracts of Lantana camara to be most effective extracts exhibiting a significant LC50 value of 30.71 ppm while the Phyllanthus emblica fruit extracts were found to be least effective with an LC50 value of 298.93 ppm. The extracts made from different parts of other five plants; Achyranthes aspera, Zingiber officinalis, Ricinus communis, Trachyspermun ammi and Cassia occidentalis also possessed significant larvicidal potential with LC¬50 values ranging from 55.0 to 74.67 ppm. Other three extracts showed moderate toxicity against Aedes aegypti larvae. Further investigations would be needed to isolate and identify the primary component responsible for the larvicidal efficiency of the

  15. Genetic profile and molecular resistance of Aedes (Stegomyia aegypti (Diptera: Culicidae in Foz do Iguaçu (Brazil, at the border with Argentina and Paraguay

    Directory of Open Access Journals (Sweden)

    Ana C. Dalla Bona

    2012-12-01

    Full Text Available The genetic variability of populations of Aedes (Stegomyia aegypti (Linnaeus, 1762 is often low due to the intense selection pressure caused by chemical control measures. In this study, we evaluated the susceptibility of larvae and adults of this mosquito to chemical insecticides, the frequency of the Val1016IIe mutation, and the genetic variability of the mitochondrial ND4 gene fragment in the urban area of Foz do Iguaçu, Paraná. The populations of A. aegypti in the southern and central regions of the city were resistant to the diagnostic dose of temephos 0.0162 ppm. Additionally, we detected difference in susceptibility in the northern population. The resistance ratios (RR95 were 3.8, 4.1, and 4.6 for the populations in the north, central, and south of the city, respectively. The entire population of A. aegypti in Foz do Iguaçu is resistant to pyrethroids. The mortality rates are as follows: 72.2% for cypermethrin (CD: 146 mg i.a./m² and 57% for deltamethrin (CD: 18 mg i.a./m². These results corroborate the hypothesis that the mutated 1016Ile allele is present in all analyzed strata. Out of the 234 samples genotyped for the Val1016Ile mutation, 15% were homozygous dominant for the wild allele (Val/Val, 62% were heterozygous (Va/Ile and 23% were homozygous for the recessive mutation (Ile/Ile. With respect to the genetic variability of the mitochondrial ND4 gene fragment, 93% of the sequences analyzed belonged to haplotype 1, and 7% belonged to haplotype 2. The genetic diversity was low, the fixation index was not significant, and gene flow was high. The control of A. aegypti in Foz do Iguaçu using temephos and pyrethroids may be compromised because of the reduced vector susceptibility. Populations of A. aegypti, that undergoes a sudden reduction in effective population size and become resistant to pyrethroids may differ from the original population in vector capacity.

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

    Science.gov (United States)

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

    2014-05-01

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

  17. Evaluation of the Toxic Effect from Eupatorium Microphyllum L.F. (Asteraceae Extracts on Aedes Aegypti Larvae (Diptera: Culicidae in Laboratory Conditions

    Directory of Open Access Journals (Sweden)

    Álvaro Rozo

    2008-07-01

    Full Text Available In the present work the toxic activity ofextracts of Eupatorium microphyllum L.F. wasevaluated on 4th instar larvae of the mosquitoAedes aegypti (Linneaus, under laboratoryconditions. Aqueous extracts were utilized inconcentrations of 500 mg L-1, 1,500 mg L-1 and2,500 mg L-1 and acetone in concentrations of10 mg L-1, 20 mg L-1, 30 mg L-1, 40 mg L-1and50 mg L-1. The bioassays were carried out fortriplicate each one with 20 larvae, exposedfor 24 hours to 150 mL of solution. In all thebioassays were employed control groups. Inthe evaluation of the acetone extracts, a negativecontrol was employed to avoid that themortality of the larvae to occur on account ofthe solvent. The Aqueous extracts showed lowmoderate action in the mortality of larvae, lessthan 20%. On the contrary, the action of theacetone extracts was observed to 10 and 20 mgL-1with 15% of mortality, while to 30 and 40mg L-1 were registered 22 to 38% of mortality.However, to 50 mg L-1 the mortality wasof 95.4% with highly significant statisticalresults. The concentrations of the acetone extractsshowed to be the most efficient for thecontrol of the mosquitoes selected. Both typesof extracts showed toxic effect in larvae of A.aegypti, nevertheless, greater effect in theacetone extracts was observed relating to theaqueous extracts of E. microphyllum, whichconstitutes a viable alternative in the search ofnew larvicides from composed natural.

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

    Science.gov (United States)

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

    2013-03-01

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

  19. Synergistic action of octopamine receptor agonists on the activity of selected novel insecticides for control of dengue vector Aedes aegypti (Diptera: Culicidae) mosquito.

    Science.gov (United States)

    Ahmed, Mohamed Ahmed Ibrahim; Vogel, Christoph Franz Adam

    2015-05-01

    Studying insecticide resistance in mosquitoes has attracted the attention of many scientists to elucidate the pathways of resistance development and to design novel strategies in order to prevent or minimize the spread and evolution of resistance. Here, we tested the synergistic action of piperonyl butoxide (PBO) and two octopamine receptor (OR) agonists, amitraz (AMZ) and chlordimeform (CDM) on selected novel insecticides to increase their lethal action on the fourth instar larvae of Aedes aegypti L. However, chlorfenapyr was the most toxic insecticide (LC50 = 193, 102, and 48 ng/ml, after 24, 48, and 72 h exposure, respectively) tested. Further, PBO synergized all insecticides and the most toxic combinatorial insecticide was nitenpyram even after 48 and 72 h exposure. In addition, OR agonists significantly synergized most of the selected insecticides especially after 48 and 72 h exposure. The results imply that the synergistic effects of amitraz are a promising approach in increasing the potency of certain insecticides in controlling the dengue vector Ae. aegypti mosquito.

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

    Institute of Scientific and Technical Information of China (English)

    Damrongpan; Thongwat; Nophawan; Bunchu

    2015-01-01

    Objective:To investigate the susceptibility to temephos.permethrin and deltamethrin of Aedes aegypti Ae.aegypti),collected from areas with high incidence of dengue hemorrhagic fever cases in Phitsanulok Province.Thailand.Methods:The F1 progenies of Ae.aegypti colony,originated from five sub-districts including Aranyik.Hua Ro,Nai Muang.Ban Krang and Tha Pho,were used in the bioassays following the procedures of World Heath Organization.For larval bioassay.the late third or early fourth-instar lanae were tested with different concentrations of temephos.For adult bioassay.the females were exposed to 0.75%permethrin or 0.05%deltamethrin.LC50value and mortality rate were analyzed to compare the insecticide susceptibility of the larvae and the adults in each area,respectively.Results:The LC50 value of temephos for the larvae from Aranyik.Hua Ro.Nai Muang,Ban Krang and Tha Pho sub-districts was 0.017.0.017.0.026.0.061.and 0.113 ppm,respectively.For permethrin,the highest morlalitv rate(86.84%) was found in the mosquitoes from Aranyik but the others were more resistant with the lower morlality rates(16.00-42.67%).The adult morlality rates after exposing to dellaiiielhrin were higher(82.34-98.67%) in all areas.Conclusions:Ae.acgypti larvae were still susceptible to temephos.Conversely,most tested adults tended to resist the penmethrin and deltamethrin.

  1. The Effectiveness of Dibutyltin (IV and Di-tert-butyltin (IV Alkyl-phenyl Dithiocarbamate Compounds as Larvicide against Aedes aegypti Linn. (Diptera: Culicidae in Laboratory

    Directory of Open Access Journals (Sweden)

    Normah Awang

    2014-10-01

    Full Text Available Extensive use of insecticides to control dengue vectors has led to the development of mosquito resistance, environmental pollution and undesirable effects on non target organisms. Thus, the potential of organotin (IV compounds has been explored to be developed as insecticides to obviate the existing problems. The aim of this study was to examine the larvicidal effect of dibutylt in (IV and di-tert-butyltin (IV alkyl-phenyl dithiocarbamate compounds against Aedes aegypti Linn. in laboratory. Larvicidal bioassay test of four compounds dibutyltin (IV ethyl phenyl dithiocarbamate, di-tert-butyltin (IV ethyl phenyl dithiocarbamate, dibutyltin (IV butyl phenyl dithiocarbamate and di-tert-butyltin (IV butyl phenyl dithiocarbamate against third instar larvae of A. aegypti was carried out. The study indicated that dibutyltin (IV butyl phenyl dithiocarbamate showed the highest larvicidal effect with LC50 and LC90 values of 0.59 and 3.91 ppm, respectively. However, the other three compounds showed lower larvicidal effects. Dibutyltin (IV ethyl phenyl dithiocarbamate showed moderate larvicidal effect with LC50 and LC90 values of 4.45 and 11.08 ppm, respectively, followed by di-tert-butyltin (IV butyl phenyl dithiocarbamate compound with LC50 and LC90 values of 5.08 and 11.50 ppm, respectively. Di-tert-butyltin (IV ethyl phenyl dithiocarbamate compound showed the least larvicidal effect with LC50 and LC90 values of 8.59 and 36.74 ppm, respectively. Morphological anomalies such as elongated neck region, shortened length and destructed digestive tract in the larvae were observed and recorded during the larvicidal bioassay testing. As a conclusion, dibutyltin (IV butyl phenyl dithiocarbamate compound is the most effective compound against the dengue vector, A. aegypti and has the potential to be explored as a larvicide. Further study is needed to ensure that this compound can be used safely as a larvicide.

  2. Bioefficacy of Plumbago zeylanica (Plumbaginaceae) and Cestrum nocturnum (Solanaceae) plant extracts against Aedes aegypti (Diptera: Culicide) and nontarget fish Poecilia reticulata.

    Science.gov (United States)

    Patil, Chandrashekhar D; Patil, Satish V; Salunke, Bipinchandra K; Salunkhe, Rahul B

    2011-05-01

    In a search for natural products that could be used to control the vectors of tropical diseases, extracts of medicinal plants Plumbago zeylanica and Cestrum nocturnum have been tested for larvicidal activity against second, third, and fourth instar larvae of Aedes aegypti. The LC(50) values of all the extracts in different solvents of both the plants were less than 50 ppm (15.40-38.50 ppm) against all tested larval instars. Plant extracts also affected the life cycle of A. aegypti by inhibition of pupal development and adult emergence with increasing concentrations. The larvicidal stability of the extracts at five constant temperatures (19°C, 22°C, 25°C, 28°C, and 31°C) evaluated against fourth instar larvae revealed that toxicity of both plant extracts increases with increase in temperature. Toxicity studies carried out against fish species Poecilia reticulata, the most common nontarget organism in the habitats of A. aegypti, showed almost nil to meager toxicity at LC(50) and LC(90) doses of the plant extracts. The qualitative analysis of crude extracts of P. Zeylanica and C. nocturnum revealed the presence of bioactive phytochemicals with predominance of plumbagin in P. zeylanica and saponins in C. nocturnum. Partially purified plumbagin from P. zeylanica and saponins from C. nocturnum were obtained, and their presence was confirmed by thin-layer chromatography and biochemical tests. The bioassay experiment of partially purified secondary metabolites showed potent mosquito larvicidal activity against the fourth instar larval form. Therefore, this study explored the safer and effective potential of plant extracts against vector responsible for diseases of public health importance. PMID:21107859

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

    Science.gov (United States)

    Muthukumaran, Udaiyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2015-03-01

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

  4. Avaliação da atividade inibidora do diflubenzuron na ecdise das larvas de Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae Evaluation of the inhibiting activity of the diflubenzuron on the ecdysis of larvae of Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Flávia Martins

    2004-03-01

    Full Text Available Foi avaliada a atividade inibidora do diflubenzuron na ecdise de larvas do Aedes aegypti, visando à utilização desse produto no controle desse mosquito. Além disso, conhecer a interação do produto com o tipo de criadouro e a suscetibilidade do mosquito. Os bioensaios foram realizados em um fundo de quintal de residência, em sete tipos potenciais de criadouros artificiais: pneu, vidro, cimento-amianto, cimento, lata, plástico e cerâmica. Para cada tipo de criadouro colocaram-se 20 larvas de cada estádio do Aedes aegypti. O mesmo número de larvas foi utilizado para o controle. Foram feitas nove réplicas e as leituras de mortalidade foram em intervalos de 24 horas, após o início dos experimentos, até atingir o índice de 100%. Isto foi obtido a 1 ppm. Não houve diferença significativa entre os períodos médios de sobrevivência das larvas e nem entre os diferentes tipos de criadouros. Houve diferenças significativas entre os estádios, sendo o 3° o mais tolerante. Constatou-se também que as concentrações não interagiram com os estádios e tipos de criadouros, ao nível de 5%.The inhibiting activity of diflubenzuron on the ecdysis of Aedes aegypti larvae was evaluated, with a view to using this product in mosquito control. This study also aimed to determine the interaction between this product, the type of artificial containers and the susceptibility of the mosquito. Bioassays were carried out in the backyard of a residence, using seven kinds of artificial habitats: tires, glass, concrete roofing, cans, plastic containers, cement and pottery. In each kind of artificial habitat, 20 Aedes aegypti larvae in the 4th instar were set. The same number of larvae was used as a control. Each test was repeated five times and the observation of mortality was done once every 24 hours, until 100% mortality was reached at 1 ppm. There was no significant difference between the main surveillance periods of the larvae, nor between the various

  5. 植物精油及化合物对埃及伊蚊幼虫的生物活性%Essential Oils and Their Compounds as Aedes aegypti L. (Diptera:Culicidae) Larvicides

    Institute of Scientific and Technical Information of China (English)

    袁建忠; 李庆凤; 黄健波

    2014-01-01

    Essential oils and their compounds exhibit bioactivity against Aedes aegypti L. (Diptera: Culicidae) larvae, which is the primary vector of dengue. More than 60%of 361 essential oils from 269 plant species were considered active(LC50﹤100 mg/L), and the majority of these active oils were derived from plant species belonging to Myrtaceae, Lamiaceae and Rutaceae. Essential oils rich in phenylpropanoids, oxygenated sesquiterpenes and monoterpene hydrocarbons were found to be the most active. This article mainly reviews activities of essential oils against A. aegypti larvae, the factors affecting activities of essential oils, structure-activity relationships of essential oil compounds and their mode of action.%植物精油及化合物对登革热的主要媒介埃及伊蚊幼虫具有杀幼虫活性。从269种植物中提取的361个植物精油中,超过60%具有较高的生物活性(LC50<100 mg/L),这些植物主要为桃金娘科、唇形科和芸香科。精油中富含苯丙烷类、倍半萜烯类和单萜烯类物质具有最高的活性。着重介绍了植物精油对埃及伊蚊幼虫的活性、影响精油的活性因素、分子结构与活性相关性及精油及化合物的作用机理。

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

    Science.gov (United States)

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

    2015-09-01

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

  8. Larvicidal, Repellent and Irritant Potential of the Seed-derived Essential oil of Apium graveolens against Dengue Vector, Aedes aegypti L. (Diptera: Culicidae

    Directory of Open Access Journals (Sweden)

    Sarita eKumar

    2014-09-01

    Full Text Available Aedes aegypti L., the primary carrier for viruses causing dengue, chikungunya and yellow fever is widespread over large areas of the tropics and subtropics. Keeping in view the adverse effects of chemical insecticides-based intervention measures; the eco-friendly, bio-degradable essential oil extracted from the seeds of celery, Apium graveolens; was investigated for anti-mosquito potential against Ae. aegypti. Evaluation of larvicidal potential of celery seed oil against early fourth instars of Ae. aegypti resulted in LC50 and LC90 values of 16.10 ppm and 29.08 ppm, respectively, after an exposure to 24 h; the toxic effect of the oil increasing by 1.2 fold with an LC50 value of 13.22 ppm after an exposure to 48h. Interestingly, the seed oil did not cause rapid mortality, suggesting a delayed type of larval killing effect. The remarkable finding of the present study was effective repellency of the essential oil leading to 100% protection till 165 min as compared to control that did not show any repellency against mosquitoes. Only 1 bite was recorded in the 165th minute after which only 2 bites were scored until 180 min of exposure of the oil to the adult mosquitoes. An exciting observation was the knocked-down of mosquitoes caused by the exposure to 10% oil-impregnated papers. The exposure to 1% oil resulted in first flight only after 4 sec and a total of 63.66 average flights during 15 min exposure revealing the relative irritability of 26.97.The qualitative phytochemical study of the oil showed the presence of terpenoids, lactones and flavonoids as the major constituents suggesting their possible role in the toxicity. Present investigations proved celery seed essential oil to be an efficient larvicide and repellent against dengue vector. Further studies are needed to identify the active principles involved, their mode of action, formulated preparations for enhancing potency and stability, toxicity and effects on non-target organisms and the

  9. Bioefficacy of larvicdial and pupicidal properties of Carica papaya (Caricaceae) leaf extract and bacterial insecticide, spinosad, against chikungunya vector, Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Kovendan, Kalimuthu; Murugan, Kadarkarai; Naresh Kumar, Arjunan; Vincent, Savariar; Hwang, Jiang-Shiou

    2012-02-01

    The present study was carried out to establish the properties of Carica papaya leaf extract and bacterial insecticide, spinosad on larvicidal and pupicidal activity against the chikungunya vector, Aedes aegypti. The medicinal plants were collected from the area around Bharathiar University, Coimbatore, India. C. papaya leaf was washed with tap water and shade-dried at room temperature. An electrical blender powdered the dried plant materials (leaves). The powder (500 g) of the leaf was extracted with 1.5 l of organic solvents of methanol for 8 h using a Soxhlet apparatus and then filtered. The crude leaf extracts were evaporated to dryness in a rotary vacuum evaporator. The plant extract showed larvicidal and pupicidal effects after 24 h of exposure; however, the highest larval and pupal mortality was found in the leaf extract of methanol C. papaya against the first- to fourth-instar larvae and pupae of values LC(50) = I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and IV instar was 82.18 ppm, and pupae was 440.65 ppm, respectively, and bacterial insecticide, spinosad against the first to fourth instar larvae and pupae of values LC(50) = I instar was 51.76 ppm, II instar was 61.87 ppm, III instar was 74.07 ppm, and IV instar was 82.18 ppm, and pupae was 93.44 ppm, respectively. Moreover, combined treatment of values of LC(50) = I instar was 55.77 ppm, II instar was 65.77 ppm, III instar was 76.36 ppm, and IV instar was 92.78 ppm, and pupae was 107.62 ppm, respectively. No mortality was observed in the control. The results that the leaves extract of C. papaya and bacterial insecticide, Spinosad is promising as good larvicidal and pupicidal properties of against chikungunya vector, A. aegypti. This is an ideal eco-friendly approach for the control of chikungunya vector, A. aegypti as target species of vector control programs.

  10. Evaluations of larvicidal activity of medicinal plant extracts to Aedes aegypti (Diptera: Culicidae) and other effects on a non target fish

    Institute of Scientific and Technical Information of China (English)

    SUWANNEE PROMSIRI; AMARA NAKSATHIT; MALEEYA KRUATRACHUE; USAVADEE THAVARA

    2006-01-01

    A preliminary study was conducted to investigate the effects of the extracts of 112 medicinal plant species, collected from the southern part of Thailand, on Aedes aegypti. Studies on larvicidal properties of plant extracts against the fourth instar larvae revealed that extracts of 14 species showed evidence of larvicidal activity. Eight out of the 14 plant species showed 100% mosquito larvae mortality. The LC50 values were less than 100μg/mL (4.1μg/ mL-89.4μg/mL). Six plant species were comparatively more effective against the fourth instar larvae at very low concentrations. These extracts demonstrated no or very low toxicity to guppy fish (Poecilia reticulata), which was selected to represent most common non-target organism found in habitats of Ae. aegypti, at concentrations active to mosquito larvae. Three medicinal plants with promising larvicidal activity, having LC50 and LC90 values being 4.1 and 16.4μg/mL for Mammea siamensis, 20.2 and 34.7μg/mL for Anethum graveolens and 67.4 and 110.3 μg/mL for Annona muricata, respectively, were used to study the impact of the extracts on the life cycle of Ae. aegypti. These plants affected pupal and adult mortality and also affected the reproductive potential of surviving adults by reducing the number of eggs laid and the percentage of egg hatchability. When each larval stage was treated with successive extracts at the LC50 value, the first instar larvae were found to be very susceptible to A. muricata and the second instar larvae were found to be susceptible to A. graveolens, while the third and fourth instar larvae were found to be susceptible to M. siamensis. These extracts delayed larval development and inhibited adult emergence and had no adverse effects on P.reticulata at LC50 and LC90 values, except for the M. siamensis extract at its LC50 value.

  11. 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...

  12. Aedes aegypti resistance to temephos in Argentina.

    Science.gov (United States)

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

    2008-12-01

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

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

    Science.gov (United States)

    Veerakumar, Kaliyan; Govindarajan, Marimuthu; Rajeswary, Mohan

    2013-12-01

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

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

    Science.gov (United States)

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

    2013-07-01

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

  15. Evaluation of the residual effect of temephos on Aedes aegypti (Diptera, Culicidae larvae in artificial containers in Manaus, Amazonas State, Brazil

    Directory of Open Access Journals (Sweden)

    Pinheiro Valéria Cristina Soares

    2002-01-01

    Full Text Available Trial tests and container observations were conducted in households to verify the residual effect of temephos in Manaus, Amazonas State, Brazil. Three plastic buckets, three tin cans, and three tires filled with water from an artesian well and larvicide were used in the experiment, with twenty-five third-instar larvae, which remained exposed for 24h, followed by mortality readings. The same types of containers were selected from common households. Collection and counts followed by chemical treatment were carried out on the larvae that were found. Follow-up was performed weekly to verify recolonization by Aedes aegypti.The experiment showed 100% mortality in the plastic buckets until day 90, and 80% in the tin cans until day 30, decreasing from day 45 onwards. Mortality in the tires decreased to 35% in the first month. Household results showed 100% mortality for all containers after 24h and differentiated values in the subsequent readings. Larvae were observed on day 35 in a tin can and on day 21 in a gallon can. There was a large diversity of results in the tires, with recolonization observed from day 7 onwards.

  16. Evaluación larvicida de suspensiones acuosas de Annona muricata Linnaeus «guanábana» sobre Aedes aegypti Linnaeus (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Miguel Bobadilla

    2013-05-01

    Full Text Available EL presente trabajo evaluó la toxicidad larvicida de suspensiones acuosas provenientes de extractos etanólicos de las semillas, flores, hojas, corteza de ramas y corteza de raíces de Annona muricata L. «guanábana» sobre larvas del IV estadio de Aedes aegypti para determinar de esta manera los niveles de susceptibilidad. El mayor efecto tóxico correspondió a la suspensión de las semillas con un 100% de mortalidad a las 24 horas a 0,5 mg/mL, seguidos por las flores a las 48 horas a 10 mg/mL y hojas a las 36 horas a 100 mg/mL. En semillas, las concentraciones letales al 50% (CL50 y 90% (CL90 a las 48 horas de exposición fueron 0,02 mg/mL y 0,11 mg/mL, en flores 3,33 y 12,16 mg/mL, en hojas 8,25 y 26,87 mg/mL y en corteza de ramas 19,21 y 97,23 mg/mL, respectivamente. Los resultados de las rectas probit-logarítmicas indicaron susceptibilidad de los individuos a cada suspensión, gracias a la acción de diversos principios activos distribuidos en todo el árbol.

  17. Unique biochemical and molecular biological mechanism of synergistic actions of formamidine compounds on selected pyrethroid and neonicotinoid insecticides on the fourth instar larvae of Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Ahmed, Mohamed Ahmed Ibrahim; Vogel, Christoph F A; Matsumura, Fumio

    2015-05-01

    We recently reported that formamidine pesticides such as amitraz and chlordimeform effectively synergize toxic actions of certain pyrethroid and neonicotinoid insecticides in some insect species on the 4th instar larvae of Aedes aegypti. Here we studied the biochemical basis of the synergistic actions of the formamidines in amplifying the toxicity of neonicotinoids and pyrethroids such as dinotefuran and thiamethoxam, as well as deltamethrin-fenvalerate type of pyrethroids. We tested the hypothesis that their synergistic actions are mediated by the octopamine receptor, and that the major consequence of octopamine receptor activation is induction of trehalase to increase glucose levels in the hemolymph. The results show that formamidines cause a significant up-regulation of the octopamine receptor and trehalase mRNA expressions. Furthermore, formamidines significantly elevate levels of free glucose when co-treated with dinotefuran, deltamethrin and fenvalerate, but not with permethrin or fenitrothion, which showed no synergistic toxic effects with formamidines. These results support the conclusion that the main mode of synergism is based on the ability to activate the octopamine receptor, which is particularly effective with insecticides causing hyperexcitation-induced glucose release and consequently leading to quick energy exhaustion.

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

    Science.gov (United States)

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

    2014-06-01

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

  19. Cumulative mortality of Aedes aegypti larvae treated with compounds

    Directory of Open Access Journals (Sweden)

    Sandra Maria Torres

    2014-06-01

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

  20. Cumulative mortality of Aedes aegypti larvae treated with compounds

    Science.gov (United States)

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

    2014-01-01

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

  1. Influence des matières végétales et des engrais NPK sur la biologie de Aedes aegypti (Diptera : Culicidae

    Directory of Open Access Journals (Sweden)

    Darriet F.

    2010-06-01

    Full Text Available Dans cette étude de laboratoire, les auteurs ont mesuré sur des femelles gravides de Aedes aegypti, l’attractivité à la ponte de milieux aqueux contenant un engrais NPK, de la matière végétale (MV et un mélange composé de MV+NPK. Tandis que les analyses physico-chimiques ont permis d’identifier puis de doser les constituants de chaque milieu, le suivi des larves et la pesée des femelles émergentes nous ont renseigné sur l’impact des composés minéraux et organiques sur le développement des moustiques. Sur les 23 jours qu’a duré l’expérience, la solution NPK est restée aussi attractive que le mélange MV+NPK sans toutefois pouvoir assurer le développement des larves. L’infusion MV a révélé une attractivité à la ponte moins importante, mais elle a apporté aux larves de moustiques les substances organiques dont la solution NPK était dépourvue. Enfin le mélange MV+NPK a attiré les femelles à la ponte tout en assurant pleinement la croissance des larves de Ae. aegypti. Alors que les analyses physico-chimiques de NPK ont révélé une composition essentiellement minérale (NH4++NO3–+P+K et celles de MV de fortes concentrations en carbone et en azote organiques, le mélange MV+NPK s’est distingué par une composition mixte organique et minérale qui a favorisé la prolifération des bactéries et le développement des larves de moustiques. Ce sont des observations importantes qui pourraient aider à la fabrication de pièges à la fois attractifs et létaux (NPK+larvicide et dont les fonctions seraient de piéger les femelles gravides à la recherche d’un lieu de ponte et de tuer les larves à l’éclosion des oeufs.

  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. Detection of dengue viral RNA in Aedes aegypti (Diptera: Culicidae) exposed to sticky lures using reverse-transcriptase polymerase chain reaction.

    Science.gov (United States)

    Bangs, M J; Tan, R; Listiyaningsih, E; Kay, B H; Porter, K R

    2001-09-01

    Active surveillance for dengue (DEN) virus infected mosquitoes can be an effective way to predict the risk of dengue infection in a given area. However, doing so may pose logistical problems if mosquitoes must be kept alive or frozen fresh to detect DEN virus. In an attempt to simplify mosquito processing, we evaluated the usefulness of a sticky lure and a seminested reverse-transcriptase polymerase chain reaction assay (RT-PCR) for detecting DEN virus RNA under laboratory conditions using experimentally infected Aedes aegypti (L.) mosquitoes. In the first experiment, 40 male mosquitoes were inoculated with 0.13 microl of a 10(4) pfu/ml DEN-2 stock solution. After a 7-d incubation period, the mosquitoes were applied to the sticky lure and kept at room temperatures of 23-30 degrees C. Following 7, 10, 14, and 28 d application, 10 mosquitoes each were removed from the lure, pooled, and assayed for virus. DEN virus nucleic acid was clearly detectable in all pools up to 28 d after death. A second study evaluated sensitivity and specificity using one, two, and five DEN-infected mosquitoes removed after 7,10, 14, 21, and 30 d application and tested by RT-PCR. All four DEN serotypes were individually inoculated in mosquitoes and evaluated using the same procedures as experiment 1. The four serotypes were detectable in as few as one mosquito 30 d after applications to the lure with no evidence of cross-reactivity. The combination of sticky lures and RT-PCR show promise for mosquito and dengue virus surveillance and warrant further evaluation. PMID:11580045

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

    Directory of Open Access Journals (Sweden)

    Adriana dos Santos Gomes

    2006-08-01

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

  5. Larvicidal activity of oil-resin fractions from the Brazilian medicinal plant Copaifera reticulata Ducke (Leguminosae-Caesalpinoideae against Aedes aegypti (Diptera, Culicidae Atividade larvicida das frações do óleo-resina da planta medicinal brasileira Copaifera reticulata Ducke (Leguminosae-Caesalpinoideae sobre o Aedes aegypti (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Heloísa Helena Garcia da Silva

    2007-06-01

    Full Text Available Oil-resin fractions from Copaifera reticulata Ducke (Leguminosae-Caesalpinoideae were evaluated for larvicidal activity on third larval instars of Aedes aegypti, in searching for alternative control methods for this mosquito. The bioactive fractions were chemically monitored by thin-layer chromatography, ¹H and 13C nuclear magnetic resonance and mass spectrometry. Bioassays were performed using five repetitions, at a temperature of 28 ± 1°C, relative humidity of 80 ± 5% and light and dark cycles of 12h. Mortality was indicated by darkening of the cephalic capsule after 24h of exposure of the larvae to the solutions. The most active fractions were CRM1-4 (sesquiterpenes and CRM5-7 (labdane diterpenes, which showed LC50 values of 0.2 and 0.8ppm, respectively.A atividade larvicida das frações do óleo-resina de Copaifera reticulata Ducke (Leguminosae-Caesalpinoideae foi avaliada em larvas de 3º estádio de Aedes aegypti, na busca de alternativas para o controle desse mosquito. As frações bioativas foram monitoradas quimicamente através de cromatografia de camada delgada, analisada por ressonância magnética nuclear de hidrogênio (¹H e 13C e espectrometria de massas. Os bioensaios foram realizados à temperatura de 28±1°C, 80±5% de umidade relativa e fotofase de 12h, com cinco repetições. A mortalidade foi determinada através do escurecimento da cápsula cefálica, após 24h de exposição das larvas às soluções. As frações mais ativas foram CRM1-4 (sesquiterpenos e CRM5-7 (diterpeno labdano, que mostraram os valores de CL50 de 0,2 e 0,8ppm, respectivamente.

  6. 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...

  7. Influência do período de quiescência dos ovos sobre o ciclo de vida de Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae em condições de laboratório

    Directory of Open Access Journals (Sweden)

    Silva Heloisa Helena Garcia da

    1999-01-01

    Full Text Available Estudou-se a influência do período de quiescência dos ovos no ciclo de vida de Aedes aegypti (Linnaeus, 1762 (Diptera, Culicidae em condições de laboratório, na busca de informações que possam melhorar o direcionamento das ações de controle, pois sabe-se que o ovo é a forma mais resistente do ciclo biológico, possibilitando ao mosquito ampla sobrevida, devido à resistência às adversidades climáticas. Os experimentos foram realizados numa câmara biológica, mantida à temperatura de 28 ± 1oC, com umidade relativa de 80 ± 5% e fotofase de 12 horas. Apresentam-se os dados da influência de diferentes períodos de quiescência sobre a eclosão das larvas, desenvolvimento larval e pupal, ciclo evolutivo. Verificou-se o efeito altamente significativo do período de quiescência na eclosão das larvas. O período de quiescência não influenciou nas durações dos períodos de incubação, larval e pupal. Constatou-se que ovos de um mesmo período de quiescência apresentaram períodos de incubação estatisticamente diferentes entre si. As larvas eclodiam em grupos, definidos pela incubação, e este efeito de grupo foi significativo na duração do ciclo. Pode-se afirmar que, em 99,8% dos ciclos, a variação foi determinada pela incubação.

  8. 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.

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

    Science.gov (United States)

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

    2016-01-01

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

  10. DETEKSI MUTASI V1016G PADA GEN VOLTAGE-GATED SODIUM CHANNEL PADA POPULASI Aedes aegypti (DIPTERA: CULICIDAE DI KABUPATEN KLATEN, JAWA TENGAH DENGAN METODE ALLELE-SPECIFIC PCR

    Directory of Open Access Journals (Sweden)

    Dyah Widiastuti

    2015-10-01

    Full Text Available AbstrakMeluasnya kejadian resistensi pada vektor virus Dengue di Jawa Tengah memerlukan strategi pengelolaan resistensi insektisida secara efektif. Oleh karena itu, informasi mengenai mutasi gen pada posisi 1016 di domain II segmen ke­6 gen VGSC pada nyamuk Aedes aegypti yang menyebabkan perubahan asam amino valin (V menjadi glisin (G akan dapat memperkuat penelitian operasional mengenai strategi pemilihan insektisida dalam program­pengendalian­vektor­Dengue.­Penelitian­ini­menggunakan­uji­Allele-Specific­Polymerase­Chain­Reaction(AS­PCR yang dapat mendeteksi mutasi V1016G. Sampel penelitian ini adalah 22 ekor nyamuk Aedes aegypti dari Kabupaten Klaten yang berumur 2­5 hari. Hasil penelitian menunjukkan bahwa 22,7% nyamuk belum mengalami mutasi (V/V, 59,1% nyamuk mengalami mutasi heterozigot (V/G dan 18,2% nyamuk mengalami mutasi homozigot (G/G. Hal ini menunjukkan indikasi terjadinya resistensi populasi nyamuk Ae.aegypti terhadap insektisida sintetik piretroid yang disebabkan oleh mekanisme knockdown resistance.Kata Kunci:­Aedes­aegypti,­mutasi­V1016G,­Allele-Specific­PCR,­VGSCAbstractInsecticides resistance has spread rapidly among dengue vectors from Central Java, and require an effective insecticide resistance management strategies.one of the resistance mechanism in Aedes aegypti may arise through knockdown resistance or kdr which consists of single point mutation within the genes that are targeted by insecticide compounds. Mutation at position 1016 in domain II, segment 6 of the Voltage Gated Sodium Channel gene in Ae. aegypti leads to a valine to glycine substitution (V1016G is associated with resistance to the type II pyrethroid. The result of this study will help us to strengthen basic and operational research on the­development­of­strategies­for­Dengue­vector­control­in­Indonesia.­This­study­utilized­an­allele-specificPolymerase Chain Reaction (AS­PCR assay that could be used to detect the V1016G

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

    NARCIS (Netherlands)

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

    2001-01-01

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

  12. Evaluation of oviposition traps as an entomological surveillance method for Aedes aegypti (Diptera, Culicidae Avaliação das armadilhas de oviposição como método de vigilância entomológica para Aedes aegypti (Diptera, Culicidae

    Directory of Open Access Journals (Sweden)

    Angelita Anália Carniel Barbosa

    2010-06-01

    Full Text Available This study aimed to describe the behavior of oviposition traps for Aedes aegypti over time, to compare it with the larval survey and to investigate the association with climatic variables. It was conducted in São José do Rio Preto city, São Paulo. Daily climatic data and fortnightly measurements for oviposition traps and larval infestation were collected from October 2003 to September 2004. Three different periods were identified in the behavior of oviposition traps' positivity and mean number of eggs: increase, plateau and decrease in values. These measurements followed the variation of climatic data from the first and third periods. High correlation was obtained between the positivity and the mean number of eggs. The oviposition traps showed higher capacity to detect the vector than did larval survey. It was observed that the first (October to December and third (May to September periods were considered to be the most suitable to use oviposition traps than larval surveys.O estudo teve como objetivos descrever o comportamento da armadilha de oviposição para Aedes aegypti ao longo do tempo, comparar com a pesquisa larvária e investigar sua associação com variáveis climáticas. O trabalho foi realizado em São José do Rio Preto, São Paulo. Entre outubro de 2003 a setembro de 2004, as armadilhas e a pesquisa larvária forneceram dados quinzenais e foram obtidos dados climáticos. Três períodos distintos foram identificados no comportamento da positividade das armadilhas e no número médio de ovos: aumento, patamar e decréscimo dos valores. Estas medidas acompanharam as variações climáticas. Alta correlação foi obtida entre a positividade e número de ovos. As armadilhas de oviposição apresentam maior capacidade para detectar o vetor do que a pesquisa larvária. Foi observado que o primeiro (outubro a dezembro e terceiro (maio a setembro períodos foram os mais adequados para utilização das armadilhas de oviposição em

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

    OpenAIRE

    Feffrey Hii Lu King

    2012-01-01

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

  14. 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.

  15. 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.

  16. 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.

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

    Science.gov (United States)

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

    2010-06-01

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

  18. Composição química e toxicidade de óleos essenciais de espécies de Piper frente a larvas de Aedes aegypti L. (Diptera: Culicidae)

    OpenAIRE

    Costa, José G.M. da; Santos, Paula F. dos; Brito, Samara A.; Rodrigues, Fabíola F.G.; Coutinho, Henrique D.M.; Marco A. Botelho; Sidney G. de Lima

    2010-01-01

    Aedes aegypti L. é um dos vetores do dengue. No Brasil, tem ganhado muita atenção no setor da saúde pública, uma vez que esta doença tem se tornando mais agressiva na forma hemorrágica na popula- ção. Esse estudo teve como objetivo investigar o efeito de óleos essenciais de Piper aduncum, Piper marginatum e Piper nigrum contra larvas de Aedes aegypti. Em um esforço para encontrar uma maneira natural, eficaz e acessível para controlar esta doença endêmica, as atividades dos óleos essenciais, a...

  19. 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.

  20. 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

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

    Science.gov (United States)

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

    2014-03-01

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

  2. Residual effect of two Bacillus thuringiensis var. israelensis products assayed against Aedes aegypti (Diptera: Culicidae in laboratory and outdoors at Rio de Janeiro, Brazil Efeito residual de duas formulações de Bacillus thuringiensis var. israelensis sobre Aedes aegypti (Diptera: Culicidae em condições de laboratório e em simulado de campo, no Rio de Janeiro, Brasil

    Directory of Open Access Journals (Sweden)

    José Bento Pereira Lima

    2005-06-01

    Full Text Available Resistance of the dengue vector to temephos stimulated its substitution for Bacillus thuringiensis var. israelensis (Bti since 2001 in Brazil. The persistence of the two Bti formulations employed at that time by the Health Ministry, Vectobac G and Aquabac G, was assayed under laboratory and outdoor conditions. Both formulations were tested at 0.2 g/10 liters of water, the same concentration applied in the field for vector control. The tests were done against Ae. aegypti third instar larvae (Rockefeller strain. In the laboratory, Vectobac G and Aquabac G caused at least 95% mortality until 101 and 45 days after treatment, respectively. In the outdoor assays, test containers of different materials were treated with either formulation and placed in a shaded area. Larvae were introduced each 3-6 days and mortality was recorded 24 and 48 hours later. In the first set of assays, performed in June 2001, mortality levels of 70% or more were attained for 2-5 weeks for both formulations in all containers. The exception was for the iron one that rusted, resulting in low mortality after seven days. In the second set of assays (August 2001, 70% mortality was attained for just 1-2 weeks for all the containers and both formulations.RESUMO Resistência do vetor de dengue, Aedes aegypti, a temephos estimulou sua substituição por Bacillus thuringiensis var. israelensis (Bti desde 2001 no Brasil. A persistência de duas formulações de Bti empregadas naquele ano pelo Ministério da Saúde, Vectobac G e Aquabac G, foi testada em condições externas e de laboratório. Ambas formulações foram testadas a 0,2 g/10 litros de água, a mesma concentração recomendada para o controle do vetor no campo. Os testes foram realizados com larvas de Ae. aegypti de terceiro estádio (linhagem Rockefeller. No laboratório, Vectobac G e Aquabac G induziram pelo menos 95% de mortalidade até 101 e 45 dias depois do tratamento, respectivamente. Nos testes externos, recipientes

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

    Science.gov (United States)

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

    2015-06-01

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

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

    OpenAIRE

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

    2004-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Jonny E Duque Luna

    2004-12-01

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

  6. A review on symmetries for certain Aedes aegypti models

    Science.gov (United States)

    Freire, Igor Leite; Torrisi, Mariano

    2015-04-01

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

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

    Science.gov (United States)

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

  8. Anti-dengue efficacy of bioactive andrographolide from Andrographis paniculata (Lamiales: Acanthaceae) against the primary dengue vector Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Edwin, Edward-Sam; Vasantha-Srinivasan, Prabhakaran; Senthil-Nathan, Sengottayan; Thanigaivel, Annamalai; Ponsankar, Athirstam; Pradeepa, Venkatraman; Selin-Rani, Selvaraj; Kalaivani, Kandaswamy; Hunter, Wayne B; Abdel-Megeed, Ahmed; Duraipandiyan, Veeramuthu; Al-Dhabi, Naif Abdullah

    2016-11-01

    The current study investigated the toxic effect of the leaf extract compound andrographolide from Andrographis paniculata (Burm.f) against the dengue vector Ae. aegypti. GC-MS analysis revealed that andrographolide was recognized as the major chemical constituent with the prominent peak area compared with other compounds. All isolated toxic compounds were purified and confirmed through RP-HPLC against chemical standards. The larvicidal assays established at 25ppm of bioactive compound against the treated instars of Ae. Aegypti showed prominent mortality compared to other treated concentrations. The percent mortality of larvae was directly proportional to concentration. The lethal concentration (LC50) was observed at 12ppm treatment concentration. The bioactive andrographolide considerably reduced the detoxifying enzyme regulations of α- and β- carboxylesterases. In contrast, the levels of GST and CYP450 significantly increase in a dose dependent manner. The andrographolide also showed strong oviposition deterrence effects at the sub-lethal dose of 12ppm. Similarly, the mean number of eggs were also significantly reduced in a dose dependent manner. At the concentration of 12ppm the effective percentage of repellency was greater than 90% with a protection time of 15-210min, compared with control. The histopathology study displayed that larvae treated with bioactive andrographolide had cytopathic effects in the midgut epithelium compared with the control. The present study established that bioactive andrographolide served as a potential useful for dengue vector management. PMID:27443607

  9. Germ band retraction as a landmark in glucose metabolism during Aedes aegypti embryogenesis

    Directory of Open Access Journals (Sweden)

    Logullo Carlos

    2010-02-01

    Full Text Available Abstract Background The mosquito A. aegypti is vector of dengue and other viruses. New methods of vector control are needed and can be achieved by a better understanding of the life cycle of this insect. Embryogenesis is a part of A. aegypty life cycle that is poorly understood. In insects in general and in mosquitoes in particular energetic metabolism is well studied during oogenesis, when the oocyte exhibits fast growth, accumulating carbohydrates, lipids and proteins that will meet the regulatory and metabolic needs of the developing embryo. On the other hand, events related with energetic metabolism during A. aegypti embryogenesis are unknown. Results Glucose metabolism was investigated throughout Aedes aegypti (Diptera embryonic development. Both cellular blastoderm formation (CBf, 5 h after egg laying - HAE and germ band retraction (GBr, 24 HAE may be considered landmarks regarding glucose 6-phosphate (G6P destination. We observed high levels of glucose 6-phosphate dehydrogenase (G6PDH activity at the very beginning of embryogenesis, which nevertheless decreased up to 5 HAE. This activity is correlated with the need for nucleotide precursors generated by the pentose phosphate pathway (PPP, of which G6PDH is the key enzyme. We suggest the synchronism of egg metabolism with carbohydrate distribution based on the decreasing levels of phosphoenolpyruvate carboxykinase (PEPCK activity and on the elevation observed in protein content up to 24 HAE. Concomitantly, increasing levels of hexokinase (HK and pyruvate kinase (PK activity were observed, and PEPCK reached a peak around 48 HAE. Glycogen synthase kinase (GSK3 activity was also monitored and shown to be inversely correlated with glycogen distribution during embryogenesis. Conclusions The results herein support the hypothesis that glucose metabolic fate changes according to developmental embryonic stages. Germ band retraction is a moment that was characterized as a landmark in glucose

  10. Lethal ovitrap deployment for Aedes aegypti control: potential implications for non-target organisms.

    Science.gov (United States)

    Long, Sharron A; Jacups, Susan P; Ritchie, Scott A

    2015-06-01

    In Australia, dengue control combines source reduction with lethal ovitraps to reduce Aedes aegypti populations during outbreaks. Lethal ovitraps are considered a sustainable and environmentally friendly method of controlling container-inhabiting mosquitoes, however, to-date, this claim has not been quantified. This study assesses the potential impact of lethal ovitraps on non-target organisms when used to control Ae. aegypti in tropical Australia. For retention of specimens, we substituted standard sticky ovitraps for lethal ovitraps. We collected 988 Ae. aegypti and 44,132 non-target specimens over 13 months from 16 sites. Although Ae. aegypti comprised only 2.2% of the total collection, they were were the eighth most dominant taxa collected, on the 93(rd) percentile. Of the non-target organisms, Collembola were the dominant taxa, 44.2%, with 36.8% and 10.5% Diptera and Hymenoptera, respectively. Of the Dipterans, 61% were family Phoridae. Lethal ovitraps were visited by 90 insect or invertebrate families in total. Ovitraps are attractive to Collembola, Phoridae, Sciaridae, Formicidae, and Culicidae, with minimal attraction by Apidae and other commonly monitored non-target organisms. For container-inhabiting mosquitoes, LOs are cost effective operationally, requiring minimal staff resources for placement and retrieval.

  11. Multiple Modes of Action of the Squamocin in the Midgut Cells of Aedes aegypti Larvae

    Science.gov (United States)

    de Paula, Sérgio Oliveira; Martins, Gustavo Ferreira; Zanuncio, José Cola

    2016-01-01

    Annonaceous acetogenins are botanical compounds with good potential for use as insecticides. In the vector, Aedes aegypti (L.) (Diptera: Culicidae), squamocin (acetogenin) has been reported to be a larvicide and cytotoxic, but the modes of action of this molecule are still poorly understood. This study evaluated the changes in the cell morphology, and in the expression of genes, for autophagy (Atg1 and Atg8), for membrane ion transporter V-ATPase, and for water channel aquaporin-4 (Aqp4) in the midgut of A. aegypti larvae exposed to squamocin from Annona mucosa Jacq. (Annonaceae). Squamocin showed cytotoxic action with changes in the midgut epithelium and digestive cells of A. aegypti larvae, increase in the expression for autophagy gene Atg1 and Atg8, decrease in the expression of V-ATPase, decrease in the expression of Aqp4 gene in LC20 and inhibition of Apq4 genes in the midgut of this vector in LC50. These multiple modes of action for squamocin are described for the first time in insects, and they are important because different sites of action of squamocin from A. mucosa may reduce the possibility of resistance of A. aegypti to this molecule. PMID:27532504

  12. Multiple Modes of Action of the Squamocin in the Midgut Cells of Aedes aegypti Larvae.

    Science.gov (United States)

    da Silva Costa, Marilza; de Paula, Sérgio Oliveira; Martins, Gustavo Ferreira; Zanuncio, José Cola; Santana, Antônio Euzébio Goulart; Serrão, José Eduardo

    2016-01-01

    Annonaceous acetogenins are botanical compounds with good potential for use as insecticides. In the vector, Aedes aegypti (L.) (Diptera: Culicidae), squamocin (acetogenin) has been reported to be a larvicide and cytotoxic, but the modes of action of this molecule are still poorly understood. This study evaluated the changes in the cell morphology, and in the expression of genes, for autophagy (Atg1 and Atg8), for membrane ion transporter V-ATPase, and for water channel aquaporin-4 (Aqp4) in the midgut of A. aegypti larvae exposed to squamocin from Annona mucosa Jacq. (Annonaceae). Squamocin showed cytotoxic action with changes in the midgut epithelium and digestive cells of A. aegypti larvae, increase in the expression for autophagy gene Atg1 and Atg8, decrease in the expression of V-ATPase, decrease in the expression of Aqp4 gene in LC20 and inhibition of Apq4 genes in the midgut of this vector in LC50. These multiple modes of action for squamocin are described for the first time in insects, and they are important because different sites of action of squamocin from A. mucosa may reduce the possibility of resistance of A. aegypti to this molecule. PMID:27532504

  13. Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection

    Science.gov (United States)

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

    2016-01-01

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

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

    Science.gov (United States)

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

    2016-09-01

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

  15. Chemical composition and larvicidal activity of edible plant-derived essential oils against the pyrethroid-susceptible and -resistant strains of Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Sutthanont, Nataya; Choochote, Wej; Tuetun, Benjawan; Junkum, Anuluck; Jitpakdi, Atchariya; Chaithong, Udom; Riyong, Doungrat; Pitasawat, Benjawan

    2010-06-01

    The chemical compositions and larvicidal potential against mosquito vectors of selected essential oils obtained from five edible plants were investigated in this study. Using a GC/MS, 24, 17, 20, 21, and 12 compounds were determined from essential oils of Citrus hystrix, Citrus reticulata, Zingiber zerumbet, Kaempferia galanga, and Syzygium aromaticum, respectively. The principal constituents found in peel oil of C. hystrix were beta-pinene (22.54%) and d-limonene (22.03%), followed by terpinene-4-ol (17.37%). Compounds in C. reticulata peel oil consisted mostly of d-limonene (62.39%) and gamma-terpinene (14.06%). The oils obtained from Z. zerumbet rhizome had alpha-humulene (31.93%) and zerumbone (31.67%) as major components. The most abundant compounds in K. galanga rhizome oil were 2-propeonic acid (35.54%), pentadecane (26.08%), and ethyl-p-methoxycinnamate (25.96%). The main component of S. aromaticum bud oil was eugenol (77.37%), with minor amounts of trans-caryophyllene (13.66%). Assessment of larvicidal efficacy demonstrated that all essential oils were toxic against both pyrethroid-susceptible and resistant Ae. aegypti laboratory strains at LC50, LC95, and LC99 levels. In conclusion, we have documented the promising larvicidal potential of essential oils from edible herbs, which could be considered as a potentially alternative source for developing novel larvicides to be used in controlling vectors of mosquito-borne disease. PMID:20618656

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

    OpenAIRE

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

    2008-01-01

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

  17. 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

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

    NARCIS (Netherlands)

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

    2011-01-01

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

  19. Chemical control of Aedes aegypti: a historical perspective

    Directory of Open Access Journals (Sweden)

    Alejandra Manjarres-Suarez

    2013-06-01

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

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

    OpenAIRE

    Andrea Gómez; Emilia Seccacini; Eduardo Zerba; Susana Licastro

    2011-01-01

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

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

    OpenAIRE

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

    2011-01-01

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

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

    Science.gov (United States)

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

    2009-12-01

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

  3. Chemical composition, larvicidal, and biting deterrent activity of essential oils of two subspecies of Tanacetum argenteum (Asterales: Asteraceae) and individual constituents against Aedes aegypti (Diptera: Culicidae).

    Science.gov (United States)

    Ali, Abbas; Tabanca, Nurhayat; Kurkcuoglu, Mine; Duran, Ahmet; Blythe, Eugene K; Khan, Ikhlas A; Baser, K Husnu Can

    2014-07-01

    Water-distilled essential oils from dried aerial parts of Tanacetum argenteum (Lam.) Willd. subsp. argenteum (Lam.) and T. argenteum (Lam.) Willd. subsp. canum (C. Koch) Grierson were analyzed by gas chromatography and gas chromatography-mass spectrometry. In total, 27 and 32 components were identified representing 97.2 and 98.7% of essential oils of subsp. argenteum and canum, respectively. Main compounds of T. argenteum subsp. argenteum were alpha-pinene (67.9%) and beta-pinene (4.8%), whereas alpha-pinene (53.6%), 1, 8-cineole (14.8%), and camphor (4.7%) were the major constituents of subsp. canum. Essential oil of T. argenteum subsp. canum at 10 microg/cm2 with Biting Deterrent Index (BDI) value of 0.73 showed activity similar to N,N-Diethyl-meta-toluamide (DEET) at 25 mol/cm2, whereas the activity of essential oil of subsp. argenteum was lower (BDI = 0.47) than subsp. canum and DEET. Based on 95% CIs, activity of beta-caryophyllene (BDI value = 0.54) and caryophyllene oxide (BDI = 0.66) were significantly lower than DEET. In larval bioassays, essential oil of T. argenteum subsp. argenteum showed LC50 value of 93.34 ppm, whereas T. argenteum subsp. canum killed only 40% of the larvae at the highest dose of 125 ppm. Among the pure compounds, beta-caryophyllene (LC50 = 26 ppm) was the most potent compound followed by caryophyllene oxide (LC50 = 29 ppm), which was also similar to (-)-beta-pinene (LC50 = 35.9 ppm) against 1-d-old Ae. aegypti larvae at 24-h post treatment. Compounds (-)-alpha-pinene and (+)-beta-pinene showed similar larvicidal activity. Activity of (+)-alpha-pinene with LC50 value of was similar to the essential oil of T. argenteum subsp. argenteum.

  4. Imidacloprid impairs the post-embryonic development of the midgut in the yellow fever mosquito Stegomyia aegypti (=Aedes aegypti).

    Science.gov (United States)

    Fernandes, K M; Gonzaga, W G; Pascini, T V; Miranda, F R; Tomé, H V V; Serrão, J E; Martins, G F

    2015-09-01

    The mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) is a vector for the dengue and yellow fever viruses. As blood digestion occurs in the midgut, this organ constitutes the route of entry of many pathogens. The effects of the insecticide imidacloprid on the survival of St. aegypti were investigated and the sub-lethal effects of the insecticide on midgut development were determined. Third instar larvae were exposed to different concentrations of imidacloprid (0.15, 1.5, 3.0, 6.0 and 15.0 p.p.m.) and survival was monitored every 24 h for 10 days. Midguts from imidacloprid-treated insects at different stages of development were dissected and processed for analyses by transmission electron microscopy, immunofluorescence microscopy and terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assays. Imidacloprid concentrations of 3.0 and 15.0 p.p.m. were found to affect midgut development similarly. Digestive cells of the fourth instar larvae (L4) midgut exposed to imidacloprid had more multilamellar bodies, abundantly found in the cell apex, and more electron-lucent vacuoles in the basal region compared with those from untreated insects. Moreover, imidacloprid interfered with the differentiation of regenerative cells, dramatically reducing the number of digestive and endocrine cells and leading to malformation of the midgut epithelium in adults. The data demonstrate that imidacloprid can reduce the survival of mosquitoes and thus indicate its potentially high efficacy in the control of St. aegypti populations.

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

    Directory of Open Access Journals (Sweden)

    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.

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

    Directory of Open Access Journals (Sweden)

    Umi Widyastuti

    2012-07-01

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

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

    Science.gov (United States)

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

    2016-05-01

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

  8. Sodium Channel Mutations and Pyrethroid Resistance in Aedes aegypti

    Directory of Open Access Journals (Sweden)

    Yuzhe Du

    2016-10-01

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

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

    Science.gov (United States)

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

    2016-05-01

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

  10. 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.

  11. 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...

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

    Science.gov (United States)

    Freire, Igor Leite; Torrisi, Mariano

    2014-04-01

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

  13. 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.

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

    Directory of Open Access Journals (Sweden)

    Ilham Syam

    2016-03-01

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

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

    Directory of Open Access Journals (Sweden)

    Feffrey Hii Lu King

    2012-09-01

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

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

    Directory of Open Access Journals (Sweden)

    S Sulaiman

    2008-12-01

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

  17. Biolarvicidal activity of Peanibacillus macerans and Bacillus subtilis isolated from the dead larvae against Aedes aegypti - Vector for Chikungunya

    Directory of Open Access Journals (Sweden)

    A. Ramathilaga

    2012-06-01

    Full Text Available Two bacterial species were isolated from dead mosquito larvae. They were identified as Peanibacillus macerans and Bacillus Subtilis. They were examined for their mosquito larvicidal activity against chikunguya vector Aedes aegypti (Diptera: Culucidae. The LC50 values of P. macerans and B. subtilis were recorded 70.99, 50*10^6 cells /ml and 58.97, 49*10^6 cells /ml for 24h and 48h, respectively. The LC50 value of the procured culture Bacillus thuringiensis subsp israelensis also detected. It was noted as 152.02 and 50*10^6 cells /ml for 24hrs and 48hrs. A. aegypti was the most susceptible to B. subtilis. It has the highest relative susceptibility (RS value.

  18. 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

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

    Science.gov (United States)

    Canyon, D V; Muller, R

    2013-12-01

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

  1. Resistance of Aedes aegypti to temephos and adaptive disadvantages

    OpenAIRE

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

    2014-01-01

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

  2. 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...

  3. 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

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

    OpenAIRE

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

    2015-01-01

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

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

    Science.gov (United States)

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

    2015-03-01

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

  6. 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

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

    Directory of Open Access Journals (Sweden)

    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.

  9. Biological differences between brackish and fresh water-derived Aedes aegypti from two locations in the Jaffna peninsula of Sri Lanka and the implications for arboviral disease transmission.

    Science.gov (United States)

    Ramasamy, Ranjan; Jude, Pavilupillai J; Veluppillai, Thabothiny; Eswaramohan, Thampoe; Surendran, Sinnathamby N

    2014-01-01

    The mainly fresh water arboviral vector Aedes aegypti L. (Diptera: Culicidae) can also undergo pre-imaginal development in brackish water of up to 15 ppt (parts per thousand) salt in coastal areas. We investigated differences in salinity tolerance, egg laying preference, egg hatching and larval development times and resistance to common insecticides in Ae. aegypti collected from brackish and fresh water habitats in Jaffna, Sri Lanka. Brackish water-derived Ae. aegypti were more tolerant of salinity than fresh water-derived Ae. aegypti and this difference was only partly reduced after their transfer to fresh water for up to five generations. Brackish water-derived Ae. aegypti did not significantly discriminate between 10 ppt salt brackish water and fresh water for oviposition, while fresh water-derived Ae. aegypti preferred fresh water. The hatching of eggs from both brackish and fresh water-derived Ae. aegypti was less efficient and the time taken for larvae to develop into pupae was prolonged in 10 ppt salt brackish water. Ae. aegypti isolated from coastal brackish water were less resistant to the organophosphate insecticide malathion than inland fresh water Ae. aegypti. Brackish and fresh water-derived Ae. aegypti however were able to mate and produce viable offspring in the laboratory. The results suggest that development in brackish water is characterised by pertinent biological changes, and that there is restricted genetic exchange between coastal brackish and inland fresh water Ae. aegypti isolates from sites 5 km apart. The findings highlight the need for monitoring Ae. aegypti developing in coastal brackish waters and extending vector control measures to their habitats.

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

    Science.gov (United States)

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

    2016-06-01

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

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

    Science.gov (United States)

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

    2014-09-01

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

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

    Directory of Open Access Journals (Sweden)

    Gustavo Ferreira Martins

    2011-05-01

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

  13. 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.

  14. Patient-based dengue virus surveillance in Aedes aegypti from Recife, Brazil

    Directory of Open Access Journals (Sweden)

    D.R.D. Guedes

    2010-06-01

    Full Text Available Background & objectives: Dengue is currently one of the most important arthropod-borne diseasesand may be caused by four different dengue virus serotypes (DENV-1 to DENV-4, transmittedmainly by Aedes aegypti (Diptera: Culicidae mosquitoes. With the lack of a dengue vaccine,vector control strategies constitute a crucial mode to prevent or reduce disease transmission. Inthis context, DENV detection in natural Ae. aegypti populations may serve as a potential additionaltool for early prediction systems of dengue outbreaks, leading to an intensification of vector controlmeasures, aimed at reducing disease transmission. In Brazil, this type of surveillance has beenperformed sporadically by a few groups and has not been incorporated as a routine activity incontrol programs. This study aimed at detecting DENV in natural Ae. aegypti from Recife,Pernambuco, to check the circulating serotypes and the occurrence of transovarial transmission inlocal mosquito populations.Methods: From January 2005 to June 2006, mosquitoes (adults and eggs were collected in houseswhere people with clinical suspicion of dengue infection lived at. RNA was extracted from pooledmosquitoes and RT-PCR was performed in these samples for detection of the four DENV serotypes.Results & conclusion: Out of 83 pools of adult mosquitoes collected in the field, nine were positivefor DENV: five for DENV-1, two for DENV-2 and two for DENV-3. From 139 pools of adultmosquitoes reared from collected eggs, there were 17 positive pools: three for DENV-1, 10 forDENV-2, and four for DENV-3. These results are discussed in the paper in regard to the localdengue epidemiological data. The conclusions clearly point to the informative power and sensitivityof DENV entomological surveillance and to the importance of including mosquito immature formsin this strategy.

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

    Science.gov (United States)

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

    2014-02-01

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

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

    OpenAIRE

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

    2011-01-01

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

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

    OpenAIRE

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

    2012-01-01

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

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

    OpenAIRE

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

    2016-01-01

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

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

    OpenAIRE

    Ilham Syam; Esse Puji Pawenrusi

    2016-01-01

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

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

    OpenAIRE

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

    2016-01-01

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

  1. 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

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

    Science.gov (United States)

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

    2016-01-01

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

  3. 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.

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

    OpenAIRE

    Hubullah Fuadzy; Joni Hendri

    2015-01-01

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

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

    OpenAIRE

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

    2014-01-01

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

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

    OpenAIRE

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

    2014-01-01

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

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

    OpenAIRE

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

    2013-01-01

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

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

    OpenAIRE

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

    2015-01-01

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

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

    OpenAIRE

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

    2015-01-01

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

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

    OpenAIRE

    Ida Bagus Ekaputra

    2014-01-01

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

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

    OpenAIRE

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

    2003-01-01

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

  12. 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.

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

    Directory of Open Access Journals (Sweden)

    Marina Stein

    2005-08-01

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

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

    Science.gov (United States)

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

    2008-12-01

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

  15. 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.

  16. 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

  17. 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

  18. 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...

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

    Science.gov (United States)

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

    2013-12-01

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

  20. Genetic relationships among populations of Aedes aegypti from Uruguay and northeastern Argentina inferred from ISSR-PCR data.

    Science.gov (United States)

    Soliani, C; Rondan-Dueñas, J; Chiappero, M B; Martínez, M; Da Rosa, E García; Gardenal, C N

    2010-09-01

    Aedes aegypti (L.) (Diptera: Culicidae), the main vector of yellow fever and dengue viruses, was eradicated from Argentina between 1955 and 1963, but reinvaded the country in 1986. In Uruguay, the species was reintroduced in 1997. In this study we used highly polymorphic inter-simple sequence repeats (ISSR) markers to analyse the genetic structure of Ae. aegypti populations from Uruguay and northeastern Argentina to identify possible colonization patterns of the vector. Overall genetic differentiation among populations was high (F(ST) = 0.106) and showed no correlation with geographic distance, which is consistent with the short time since the reintroduction of the species in the area. Differentiation between pairs of Argentine populations (F(ST) 0.072 to 0.221) was on average higher than between Uruguayan populations (F(ST)-0.044 to 0.116). Bayesian estimation of population structure defined four genetic clusters and most populations were admixtures of two of them: Mercedes and Treinta y Tres (Uruguay) were mixtures of clusters 1 and 3; Salto (Uruguay) and Paraná (Argentina) of clusters 1 and 4; Fray Bentos (Uruguay) of clusters 2 and 3, and Gualeguaychú (Argentina) of clusters 2 and 3. Posadas and Buenos Aires in Argentina were fairly genetically homogeneous. Our results suggest that Ae. aegypti recolonized Uruguay from bordering cities in Argentina via bridges over the Uruguay River and also from Brazil.

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

    Directory of Open Access Journals (Sweden)

    Hubullah Fuadzy

    2015-10-01

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

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

    Directory of Open Access Journals (Sweden)

    Marina Stein

    2002-10-01

    Full Text Available Se identificaron criaderos de Aedes (Stegomyia aegypti en dos ciudades de la provincia del Chaco (Noreste de Argentina: Presidencia Roque Saenz Peña y Machagai. Los recipientes encontrados en los patios de las viviendas capaces de colectar agua se clasificaron según tipo y tamaño, se contaron y examinaron. Aedes aegypti y Culex quinquefasciatus fueron las especies mas abundantes, encontrándose además Cx. maxi, Cx. saltanensis y Ochlerotatus scapularis. Los neumáticos y cajas de baterías para autos fueron los recipientes que más aportaron a la producción de formas inmaduras de los culícidos colectados. Las lluvias fueron un factor importante para la proliferacion de Ae. aegypti, así como también el habito comun en la población de guardar recipientes en sus casas que permitan el desarrollo de estos culícidos.Breeding containers for Aedes (Stegomyia aegypti were identified in two cities of Chaco Province (northeast Argentina: Presidencia Roque Saenz Peña and Machagai. All water-retaining recipients found in house backyards capable to retain water were classified according to their type and size, counted and checked. Aedes aegypti and Culex quinquefasciatus were the most frequently collected species, being also found Cx. maxi, Cx. saltanensis and Ochlerotatus scapularis. Tires and car batteries represented the most important type of container where immature forms of culicids could be found. Rain was an important factor for Ae. aegypti proliferation, as well as the widespread habit of the population of keeping useless containers at home, which allows the development of culicids.

  3. 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

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

    Science.gov (United States)

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

    2016-03-01

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

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

    Science.gov (United States)

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

    1994-06-01

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

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

    Science.gov (United States)

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

    1998-03-01

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

  7. 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.

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

    Institute of Scientific and Technical Information of China (English)

    Anitha Rajasekaran; Geethapriya Duraikannan

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Safitri -

    2013-12-01

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

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

    Science.gov (United States)

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

    2015-12-01

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

  11. Avaliação da ação inseticida de extratos vegetais, óleos essenciais e substâncias sobre imaturos de Aedes aegypti (linnaeus, 1762) (Diptera:Culicidae), em condições de laboratório

    OpenAIRE

    Souza, Lígia Moraes Barizon de

    2013-01-01

    Resumo: O vírus causador do dengue é transmito ao ser humano através da picada de fêmeas de Aedes aegypti. Na ausência de uma vacina eficaz, o único método atualmente disponível ao combate da doença é o controle do mosquito Ae. aegypti. Extratos vegetais surgem como alternativa de encontrar substâncias com propriedades inseticidas contra o vetor do dengue, assim como atuarem como métodos alternativos aos inseticidas os quais os mosquitos já possuem resistência. Pela necessidade de realizar bi...

  12. 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 ...

  13. 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...

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

    OpenAIRE

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

    2012-01-01

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

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

    OpenAIRE

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

    1998-01-01

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

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

    OpenAIRE

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

    2015-01-01

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

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

    OpenAIRE

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

    2004-01-01

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

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

    OpenAIRE

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

    2016-01-01

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

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

    Science.gov (United States)

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

    1993-10-01

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

  20. 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...

  1. 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...

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

    OpenAIRE

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

    2016-01-01

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

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

    OpenAIRE

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

    2009-01-01

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

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

    OpenAIRE

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

    2012-01-01

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

  5. 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

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

    OpenAIRE

    Federico Costa; Gladys Fattore; Marcelo Abril

    2012-01-01

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

  7. 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...

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

    Institute of Scientific and Technical Information of China (English)

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

    2010-01-01

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

  9. 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...

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

    OpenAIRE

    Safitri -

    2013-01-01

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

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

    Directory of Open Access Journals (Sweden)

    José Eduardo Bracco

    1995-04-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Rina Marina

    2012-06-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  15. Temephos resistance and esterase activity in the mosquito Aedes aegypti in Havana, Cuba increased dramatically between 2006 and 2008.

    Science.gov (United States)

    Bisset, J A; Rodríguez, M M; Ricardo, Y; Ranson, H; Pérez, O; Moya, M; Vázquez, A

    2011-09-01

    Aedes aegypti (L.) (Diptera: Culicidae) control programmes in Cuba rely on the application of the organophosphate temephos for larval control. Hence, the monitoring of resistance to this insecticide is an essential component of such programmes. Here, 15 field populations from different municipalities of Havana City were assayed for resistance to temephos. High levels of resistance were detected in all strains and resistance ratios were highly correlated with esterase activity (P = 0.00001). Populations from three municipalities were tested in both 2006 and 2008; resistance and esterase activities both significantly increased during this 2-year period. Synergist studies demonstrated that neither glutathione transferases nor monooxygenases were associated with the increase in resistance to temephos in this period. The duration of the efficacy of commercial formulations of temephos in controlling Ae. aegypti populations in Havana City was reduced by the high level of temephos resistance observed; hence these data are of clear operational significance for the dengue control programme in Cuba. New integrated strategies to avoid further increases in temephos resistance in Cuba are necessary.

  16. Developing new approaches for detecting and preventing Aedes aegypti population outbreaks: basis for surveillance, alert and control system

    Directory of Open Access Journals (Sweden)

    Lêda Regis

    2008-02-01

    Full Text Available A new approach to dengue vector surveillance based on permanent egg-collection using a modified ovitrap and Bacillus thuringiensis israelensis(Bti was evaluated in different urban landscapes in Recife, Northeast Brazil. From April 2004 to April 2005, 13 egg-collection cycles of four weeks were carried out. Geo-referenced ovitraps containing grass infusion, Bti and three paddles were placed at fixed sampling stations distributed over five selected sites. Continuous egg-collections yielded more than four million eggs laid into 464 sentinel-ovitraps over one year. The overall positive ovitrap index was 98.5% (over 5,616 trap observations. The egg density index ranged from 100 to 2,500 eggs per trap-cycle, indicating a wide spread and high density of Aedes aegypti (Diptera: Culicidae breeding populations in all sites. Fluctuations in population density over time were observed, particularly a marked increase from January on, or later, according to site. Massive egg-collection carried out at one of the sites prevented such a population outbreak. At intra-site level, egg counts made it possible to identify spots where the vector population is consistently concentrated over the time, pinpointing areas that should be considered high priority for control activities. The results indicate that these could be promising strategies for detecting and preventing Ae. aegypti population outbreaks.

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

    Science.gov (United States)

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

    2015-12-01

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

  18. 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

  19. 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...

  20. "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.

  1. 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.

  2. 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,

  3. 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

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

    Science.gov (United States)

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

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

    Directory of Open Access Journals (Sweden)

    Yuneu Yuliasih

    2011-06-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  7. 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

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

    Directory of Open Access Journals (Sweden)

    Manuel Espinosa

    2014-04-01

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

  9. 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

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

    Science.gov (United States)

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

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

    Science.gov (United States)

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

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

    NARCIS (Netherlands)

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

    2013-01-01

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

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

    Science.gov (United States)

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

  14. 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...

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

    Directory of Open Access Journals (Sweden)

    Firda Yanuar Pradani

    2013-12-01

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

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

    Directory of Open Access Journals (Sweden)

    Hubullah Fuadzy

    2015-04-01

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

  17. 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

  18. 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

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

    Directory of Open Access Journals (Sweden)

    Macoris Maria de Lourdes G

    2003-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Amrul Munif

    2012-09-01

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

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

    Directory of Open Access Journals (Sweden)

    Dyah Widiastuti

    2015-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Ricardo Lourenço-de-Oliveira

    2002-04-01

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

  3. 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...

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

    Directory of Open Access Journals (Sweden)

    Massamba Sylla

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

  5. The complete mitochondrial DNA genome of Aedes vigilax (Diptera: Culicidae).

    Science.gov (United States)

    Hardy, C M; Court, L N; Morgan, M J

    2016-07-01

    The complete mitochondrial genomes of two main clades of the medically significant saltmarsh mosquito Aedes vigilax Skuse (Diptera: Culicidae) were obtained using combined Illumina and Sanger sequencing. The two 15,877 bp circular genomes share 99.0% nucleotide identity and encode 37 genes with identical gene arrangement similar to previously published Culicidae species with a non-coding A + T rich region between rns and tRNA-Ile. Protein initiation codon is ATN apart from ND5 (GTG) and COX1 (TCG). Eight protein-coding genes encode full TAA stop codon, while five are completed by mRNA polyadenylation. Typical cloverleaf structures containing DHU and TΨC stem and loops can be inferred for all 22 tRNAs. PMID:26099979

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

    OpenAIRE

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

    2012-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Genevieve LaCon

    2014-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Laura B Dickson

    2014-10-01

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

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

    Science.gov (United States)

    Lee, Hoi-Seon

    2006-06-01

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

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

    Directory of Open Access Journals (Sweden)

    Rahman G M Saifur

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

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

    Directory of Open Access Journals (Sweden)

    Dia Ibrahima

    2012-10-01

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

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

    Institute of Scientific and Technical Information of China (English)

    Michael RusselleAlvarez; Francisco Heralde III; Noel Quiming

    2016-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Damar Tri Boewono

    2012-11-01

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

  14. 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.

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

    Science.gov (United States)

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

    2012-04-01

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

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

    Science.gov (United States)

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

    2016-01-01

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

  17. 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

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

    Directory of Open Access Journals (Sweden)

    G Albrieu Llinás

    2010-02-01

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

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

    OpenAIRE

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

    2012-01-01

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

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

    Science.gov (United States)

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

    2015-08-01

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

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ke-Xin Yu

    2015-08-01

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

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

    Directory of Open Access Journals (Sweden)

    Riyani Setiyaningsih

    2014-06-01

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

  4. Potential of crude seed extract of celery, Apium graveolens L. Against Aedes aegypti L. (Diptera: Culicidae)%旱芹籽粗提取物对埃及伊蚊的效果评定

    Institute of Scientific and Technical Information of China (English)

    Wej Choochote; 郑剑宁; 裘炯良; 杨定波

    2005-01-01

    埃及伊蚊(Aedes aegypti)是众所周知的虫媒病毒性疾病——登革热的传播媒介,分布于东南亚、太平洋岛屿、非洲和美洲。它也是中美、南美和西非传播黄热病的媒介。登革热因报告的病例数逐年上升,尤其是因该病有多种类型——登革出血热、登革休克综合症和其他诸如侵犯中枢神经系统等少见类型,已成为当今社会严重的公共卫生问题。据2003年世界卫生组织的报告,全球受到登革热威胁的人口约占全球人口总数的40%。目前,减少该病发生的最有效措施是加强个人防护和控制埃及伊蚊。

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

    Science.gov (United States)

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

    2015-01-01

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

  6. 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

  7. 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

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

    Directory of Open Access Journals (Sweden)

    M. Soekirno

    2012-09-01

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

  9. 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...

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

    International Nuclear Information System (INIS)

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

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

    OpenAIRE

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

    2012-01-01

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

  13. 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...

  14. 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...

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

    OpenAIRE

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

    2010-01-01

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

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

    OpenAIRE

    Ekasari, Ranti; Ishak, Hasanuddin; Manyullei, Syamsuar

    2015-01-01

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

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

    OpenAIRE

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

    2008-01-01

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

  18. 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...

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

    OpenAIRE

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

    2012-01-01

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

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

    OpenAIRE

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

    2011-01-01

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

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

    Directory of Open Access Journals (Sweden)

    M. Hasyimi

    2012-09-01

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

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

    OpenAIRE

    Susilawati; Hermansyah

    2015-01-01

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

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

    OpenAIRE

    Thirumalapura Krishnaiah Mohankumar; Kumuda Sathigal Shivanna; Vijayan Valiakottukal Achuttan

    2016-01-01

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

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

    OpenAIRE

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

    2013-01-01

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

  5. 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...

  6. 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...

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

    OpenAIRE

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

    2009-01-01

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

  8. 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...

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

    Science.gov (United States)

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

    2014-01-01

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

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

    Science.gov (United States)

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

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

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

    Science.gov (United States)

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

    2006-12-01

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

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

    Science.gov (United States)

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

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

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

    Directory of Open Access Journals (Sweden)

    K. Vijayakumar

    2014-01-01

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

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

    Directory of Open Access Journals (Sweden)

    Ricardo Antonio Polanczyk

    2003-12-01

    Full Text Available Relata-se a importância da bactéria entomopatogênica Bacillus thuringiensis israelensis para o controle de Aedes aegypti. São abordados a utilização e potencial de B. thuringiensis israelensis contra o mosquito vetor da dengue. Outros aspectos são discutidos como a evolução da resistência dos insetos em relação aos inseticidas químicos e as vantagens e desvantagens do controle microbiano como estratégia de controle. É dada ênfase à importância da utilização desta bactéria no Brasil como alternativa para resolver o problema em questão sem afetar o ambiente, o homem e outros vertebrados nas áreas de risco.The importance of the entomopathogenic bacterium Bacillus thuringiensis israelensis in the control of Aedes aegypti is presented. The use and potential of B. thuringiensis israelensis against the mosquito vector of dengue fever is described. Other aspects such as insect's resistance development against chemicals and advantages and constraints of using microbial control are discussed. Emphasis is given to the importance of the use of this bacterium in Brazil, which could contribute significantly to solving the mosquito problem without affecting the environment, humans and others invertebrate organisms in critical regions.

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

    Directory of Open Access Journals (Sweden)

    R.K. Singh

    2014-09-01

    Full Text Available Temephos is used as a larvicide in urban areas in India to control the population of mosquito vectors viz. Anopheles stephensi and Aedes aegypti. The susceptibility status of Ae. aegypti and An. stephensi to temophos in various zones of Municipal Corporation of Delhi was evaluated using the WHO method for determining larval susceptibility test kit. Results revealed that the larval mortality of Ae. aegypti collected from different localities ranged between 64.88% to 98.22%. The highest mortality was recorded from Sangam Vihar (98.22% and lowest was recorded from Majnu ka tila (64.88%. Ae. aegypti larvae collected from Sangam Vihar locality was found fully susceptible to temephos, from two localities viz. Uttam Nagar and Pitampura of study area were tolerant to temephos, and from five localities viz. Majnu ka tila, Shastri Park, Mayur Vihar II, Tilak Bridge and Nagal Dewat showed development of resistance against temephos at diagnostic concentrations. However, larval populations of An. stephensi were fully susceptible to temephos in all the localities. The present study indicates the possible development of resistance against temephos in the larvae of Ae. aegypti in some areas in Delhi.

  16. QTL mapping of genome regions controlling temephos resistance in larvae of the mosquito Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    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.

  17. Genome Investigations of Vector Competence in Aedes aegypti to Inform Novel Arbovirus Disease Control Approaches

    Directory of Open Access Journals (Sweden)

    David W. Severson

    2016-10-01

    Full Text Available Dengue (DENV, yellow fever, chikungunya, and Zika virus transmission to humans by a mosquito host is confounded by both intrinsic and extrinsic variables. Besides virulence factors of the individual arboviruses, likelihood of virus transmission is subject to variability in the genome of the primary mosquito vector, Aedes aegypti. The “vectorial capacity” of A. aegypti varies depending upon its density, biting rate, and survival rate, as well as its intrinsic ability to acquire, host and transmit a given arbovirus. This intrinsic ability is known as “vector competence”. Based on whole transcriptome analysis, several genes and pathways have been predicated to have an association with a susceptible or refractory response in A. aegypti to DENV infection. However, the functional genomics of vector competence of A. aegypti is not well understood, primarily due to lack of integrative approaches in genomic or transcriptomic studies. In this review, we focus on the present status of genomics studies of DENV vector competence in A. aegypti as limited information is available relative to the other arboviruses. We propose future areas of research needed to facilitate the integration of vector and virus genomics and environmental factors to work towards better understanding of vector competence and vectorial capacity in natural conditions.

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

    Directory of Open Access Journals (Sweden)

    Jill N Ulrich

    2016-07-01

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

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

    Science.gov (United States)

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

    2016-07-01

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

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

    Directory of Open Access Journals (Sweden)

    Goncalo Seixas

    2013-01-01

    Full Text Available The increasing population of Aedes aegypti mosquitoes on Madeira Island (Portugal resulted in the first autochthonous dengue outbreak, which occurred in October 2012. Our study establishes the first genetic evaluation based on the mitochondrial DNA (mtDNA genes [cytochrome oxidase subunit I (COI and NADH dehydrogenase subunit 4 (ND4] and knockdown resistance ( kdr mutations exploring the colonisation history and the genetic diversity of this insular vector population. We included mosquito populations from Brazil and Venezuela in the analysis as putative geographic sources. The Ae. aegypti population from Madeira showed extremely low mtDNA genetic variability, with a single haplotype for COI and ND4. We also detected the presence of two important kdr mutations and the quasi-fixation of one of these mutations (F1534C. These results are consistent with a unique recent founder event that occurred on the island of Ae. aegypti mosquitoes that carry kdr mutations associated with insecticide resistance. Finally, we also report the presence of the F1534C kdr mutation in the Brazil and Venezuela populations. To our knowledge, this is the first time this mutation has been found in South American Ae. aegypti mosquitoes. Given the present risk of Ae. aegypti re-invading continental Europe from Madeira and the recent dengue outbreaks on the island, this information is important to plan surveillance and control measures.

  1. Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development

    Science.gov (United States)

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

    2016-01-01

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

  2. Excito-repellency of essential oils against an Aedes aegypti (L.) field population in Thailand.

    Science.gov (United States)

    Boonyuan, Wasana; Grieco, John P; Bangs, Michael J; Prabaripai, Atchariya; Tantakom, Siripun; Chareonviriyaphap, Theeraphap

    2014-06-01

    An investigation of the behavioral responses of Aedes aegypti (= Stegomyia aegypti) to various concentrations of essential oils (2.5, 5, and 10%) extracted from hairy basil (Ocimum americanum Linn), ginger (Zingiber officinale Roscoe), lemongrass (Cymbopogon citratus Stapf), citronella grass (Cymbopogon nardus Rendle), and plai (Zingiber cassumunar Roxb) were performed using an excito-repellency test chamber. Results showed that Ae. aegypti exhibited varying levels of escape response in both the contact and noncontact chambers in response to different essential oils. The magnitude of the behaviors changed in a dose-response fashion depending on the percent volume to volume concentration of oil used. A 2.5% concentration of hairy basil oil produced a significantly greater escape response compared to the other extracts at the same concentration (Pinsecticidal activity to Ae. aegypti, with LC50 values of 6.3 and 6.7 percent, respectively. We conclude that the essential oils from native plants tested, and likely many other extracts found in plants, have inherent repellent and irritant qualities that should to be screened and optimized for their behavior-modifying properties against Ae. aegypti and other biting arthropods of public health and pest importance.

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

    Science.gov (United States)

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

    2016-07-01

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

  4. 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...

  5. 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...

  6. Surveillance and control of Aedes aegypti in epidemic areas of Taiwan.

    Science.gov (United States)

    Lin, T H

    1994-12-01

    Aedes aegypti is the main, if not the only, vector of dengue fever in Taiwan. The dengue epidemics that have occurred in Taiwan correlate with the distribution of Aedes aegypti which is limited to south of the Tropic of Cancer. During the 1987 outbreak of dengue fever in Taiwan, the average larval density for the months July-December in the five cities and counties of southern Taiwan was 2,284 larvae per 100 households. After control measures were taken, the average annual larval density in the years from 1988 to 1993 declined to 1,580, 671, 442, 178, 110, and 88 larvae per 100 households, respectively. During 1987-1988, the number of confirmed cases and the Breteau index of Aedes aegypti showed an obvious positive relationship (r = 0.74) in the most heavily infected 25 cities and towns. Our Institute has conducted eight training courses since 1989 for 176 health workers who serve in their respective areas as local scouts for monitoring Aedes larval density. The number of cities and towns surveyed by them in the years 1990-1993 was 116, 149, 254, and 156, respectively. The number of households covered by space spraying with permethrin was 43, 183 in 1991, 11,186 in 1992 and 4,856 in 1993. Residual spraying with alphacypermethrin was applied to houses in areas where the Breteau index was above 35. The number of houses treated in the years 1990-1993 was 4,735, 32,279, 33,726 and 17,848, respectively.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Ecological modeling of Aedes aegypti (L. pupal production in rural Kamphaeng Phet, Thailand.

    Directory of Open Access Journals (Sweden)

    Jared Aldstadt

    Full Text Available BACKGROUND: Aedes aegypti (L. is the primary vector of dengue, the most important arboviral infection globally. Until an effective vaccine is licensed and rigorously administered, Ae. aegypti control remains the principal tool in preventing and curtailing dengue transmission. Accurate predictions of vector populations are required to assess control methods and develop effective population reduction strategies. Ae. aegypti develops primarily in artificial water holding containers. Release recapture studies indicate that most adult Ae. aegypti do not disperse over long distances. We expect, therefore, that containers in an area of high development site density are more likely to be oviposition sites and to be more frequently used as oviposition sites than containers that are relatively isolated from other development sites. After accounting for individual container characteristics, containers more frequently used as oviposition sites are likely to produce adult mosquitoes consistently and at a higher rate. To this point, most studies of Ae. aegypti populations ignore the spatial density of larval development sites. METHODOLOGY: Pupal surveys were carried out from 2004 to 2007 in rural Kamphaeng Phet, Thailand. In total, 84,840 samples of water holding containers were used to estimate model parameters. Regression modeling was used to assess the effect of larval development site density, access to piped water, and seasonal variation on container productivity. A varying-coefficients model was employed to account for the large differences in productivity between container types. A two-part modeling structure, called a hurdle model, accounts for the large number of zeroes and overdispersion present in pupal population counts. FINDINGS: The number of suitable larval development sites and their density in the environment were the primary determinants of the distribution and abundance of Ae. aegypti pupae. The productivity of most container types

  8. Maya Index and Larva Density Aedes Aegypti Toward Dengue Infection

    OpenAIRE

    Sang G. Purnama; Tri Baskoro

    2012-01-01

    South Denpasar District was of there as with the highest dengue cases in Bali province. The number of mosquito breeding places and larvae density become risk factor that influenced the spreading of mosquitoes. Maya index was an indicator to measure the amount of waterreservoirs can be breeding places for mosquitoes. Knowing the relationship between maya index and density of larvae and pupae of Ae.aegypti toward dengue infection in South Denpasar District. The study was observational analytic ...

  9. Costs of Three Wolbachia Infections on the Survival of Aedes aegypti Larvae under Starvation Conditions.

    Directory of Open Access Journals (Sweden)

    Perran A Ross

    2016-01-01

    Full Text Available The mosquito Aedes aegypti, the principal vector of dengue virus, has recently been infected experimentally with Wolbachia: intracellular bacteria that possess potential as dengue biological control agents. Wolbachia depend on their hosts for nutrients they are unable to synthesize themselves. Consequently, competition between Wolbachia and their host for resources could reduce host fitness under the competitive conditions commonly experienced by larvae of Ae. aegypti in the field, hampering the invasion of Wolbachia into natural mosquito populations. We assess the survival and development of Ae. aegypti larvae under starvation conditions when infected with each of three experimentally-generated Wolbachia strains: wMel, wMelPop and wAlbB, and compare their fitness to wild-type uninfected larvae. We find that all three Wolbachia infections reduce the survival of larvae relative to those that are uninfected, and the severity of the effect is concordant with previously characterized fitness costs to other life stages. We also investigate the ability of larvae to recover from extended food deprivation and find no effect of Wolbachia on this trait. Aedes aegypti larvae of all infection types were able to resume their development after one month of no food, pupate rapidly, emerge at a large size, and exhibit complete cytoplasmic incompatibility and maternal transmission. A lowered ability of Wolbachia-infected larvae to survive under starvation conditions will increase the threshold infection frequency required for Wolbachia to establish in highly competitive natural Ae. aegypti populations and will also reduce the speed of invasion. This study also provides insights into survival strategies of larvae when developing in stressful environments.

  10. UJI REPELEN (DAYA TOLAK BEBERAPA EKSTRAK TUMBUHAN TERHADAP GIGITAN NYAMUK Aedes aegypti VEKTOR DEMAM BERDARAH DENGUE

    Directory of Open Access Journals (Sweden)

    Hasan Boesri Boesri

    2015-10-01

    Full Text Available AbstrakPenyakit­ Demam ­Berdarah ­Dengue,­Malaria,­filaria­sejauh­ini­masih­menjadi­masalah­kesehatan­masyarakat.Penggunaan insektisida nabati banyak memberikan keuntungan diantaranya ramah lingkungan, tidak memberikan dampak buruk pada kesehatan dan bahan dasar ada di sekitar pemukiman. Berdasarkan banyaknya keuntungan yang didapatkan, maka dipandang perlu untuk mencari insektisida nabati sebagai repelen untuk  menolak gigitan nyamuk  penular penyakit. Penelitian ini merupakan eksperimen murni, tentang pembuatan ekstrak dari berbagai­bahan­tanaman­serta­uji­efektifitas­daya­tolak­nyamuknya­dan­dilakukan­di­laboratorium.­Pembuatanekstrak dilakukan di Laboratorium Farmasi Universitas Gajah Mada Yogyakarta, sedangkan  untuk pengujian ekstrak terhadap nyamuk Aedes aegypti dilakukan di laboratorium uji insektisida Balai Besar Litbang Vektor dan Reservoir Penyakit. Hasil penelitian uji  repelen beberapa ekstrak tumbuhan adalah pada dosis 100%  yang mampu menolak gigitan nyamuk di atas 80% per jam  antara lain ekstrak daun Zodia mampu menolak sampai 2 jam sebanyak 88,2%. Ekstrak daun tembakau  mampu menolak  selama 3 jam sebanyak  84,9%, ekstrak daun gondopuro mampu menolak selama 1 jam sebanyak  83,3%,  ekstrak daun Serai Wangi mampu menolak selama 2 jam sebanyak 85,1%. Ekstrak daun cengkeh mampu menolak selama 4 jam sebanyak, 81,7%. Ekstrak bunga krisan mampu menolak selama 1 jam sebanyak 89,6%, Sedangkan ekstrak daun suren, akar tuba dan lavender hanya mampu menolak gigitan nyamuk Aedes aegypti di bawah 80%.Kata kunci : ekstrak, repelen, Aedes aegyptiAbstractDengue­Haemorrhagic­Fever,­malaria,­filaria­so­far­are­public­health­problem.­The­use­of­plant-based­­insecticidesare­many­eco-friendly­benefits,­do­not­give­bad­impact­on­­health­and­basic­materials­are­all­around­settlements.­Itis necessary to look for botanical insecticides as repellent to resist bites mosquito

  11. UDP-N-Acetyl glucosamine pyrophosphorylase as novel target for controlling Aedes aegypti – molecular modeling, docking and simulation studies

    Directory of Open Access Journals (Sweden)

    Bhagath Kumar Palaka

    2014-12-01

    Full Text Available Aedes aegypti is a vector that transmits diseases like dengue fever, chikungunya, and yellow fever. It is distributed in all tropical and subtropical regions of the world. According to WHO reports, 40% of the world’s population is currently at risk for dengue fever. As vaccines are not available for such diseases, controlling mosquito population becomes necessary. Hence, this study aims at UDP-N-acetyl glucosamine pyrophosphorylase of Aedes aegypti (AaUAP, an essential enzyme for chitin metabolim in insects, as a drug target. Structure of AaUAP was predicted and validated using in-silico approach. Further, docking studies were performed using a set of 10 inhibitors out of which NAG9 was found to have good docking score, which was further supported by simulation studies. Hence, we propose that NAG9 can be considered as a potential hit in designing new inhibitors to control Aedes aegypti.

  12. Weather Variability Associated with Aedes (Stegomyia) aegypti (Dengue Vector) Oviposition Dynamics in Northwestern Argentina.

    Science.gov (United States)

    Estallo, Elizabet L; Ludueña-Almeida, Francisco F; Introini, María V; Zaidenberg, Mario; Almirón, Walter R

    2015-01-01

    This study aims to develop a forecasting model by assessing the weather variability associated with seasonal fluctuation of Aedes aegypti oviposition dynamic at a city level in Orán, in northwestern Argentina. Oviposition dynamics were assessed by weekly monitoring of 90 ovitraps in the urban area during 2005-2007. Correlations were performed between the number of eggs collected weekly and weather variables (rainfall, photoperiod, vapor pressure of water, temperature, and relative humidity) with and without time lags (1 to 6 weeks). A stepwise multiple linear regression analysis was performed with the set of meteorological variables from the first year of study with the variables in the time lags that best correlated with the oviposition. Model validation was conducted using the data from the second year of study (October 2006- 2007). Minimum temperature and rainfall were the most important variables. No eggs were found at temperatures below 10 °C. The most significant time lags were 3 weeks for minimum temperature and rains, 3 weeks for water vapor pressure, and 6 weeks for maximum temperature. Aedes aegypti could be expected in Orán three weeks after rains with adequate min temperatures. The best-fit forecasting model for the combined meteorological variables explained 70 % of the variance (adj. R(2)). The correlation between Ae. aegypti oviposition observed and estimated by the forecasting model resulted in rs = 0.80 (P vector activity can be predicted three or four weeks in advance. PMID:25993415

  13. 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.

  14. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

    Directory of Open Access Journals (Sweden)

    Marina Stein

    2002-10-01

    Full Text Available Se identificaron criaderos de Aedes (Stegomyia aegypti en dos ciudades de la provincia del Chaco (Noreste de Argentina: Presidencia Roque Saenz Peña y Machagai. Los recipientes encontrados en los patios de las viviendas capaces de colectar agua se clasificaron según tipo y tamaño, se contaron y examinaron. Aedes aegypti y Culex quinquefasciatus fueron las especies mas abundantes, encontrándose además Cx. maxi, Cx. saltanensis y Ochlerotatus scapularis. Los neumáticos y cajas de baterías para autos fueron los recipientes que más aportaron a la producción de formas inmaduras de los culícidos colectados. Las lluvias fueron un factor importante para la proliferacion de Ae. aegypti, así como también el habito comun en la población de guardar recipientes en sus casas que permitan el desarrollo de estos culícidos.

  15. Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

    Directory of Open Access Journals (Sweden)

    Stein Marina

    2002-01-01

    Full Text Available Se identificaron criaderos de Aedes (Stegomyia aegypti en dos ciudades de la provincia del Chaco (Noreste de Argentina: Presidencia Roque Saenz Peña y Machagai. Los recipientes encontrados en los patios de las viviendas capaces de colectar agua se clasificaron según tipo y tamaño, se contaron y examinaron. Aedes aegypti y Culex quinquefasciatus fueron las especies mas abundantes, encontrándose además Cx. maxi, Cx. saltanensis y Ochlerotatus scapularis. Los neumáticos y cajas de baterías para autos fueron los recipientes que más aportaron a la producción de formas inmaduras de los culícidos colectados. Las lluvias fueron un factor importante para la proliferacion de Ae. aegypti, así como también el habito comun en la población de guardar recipientes en sus casas que permitan el desarrollo de estos culícidos.

  16. Larvicidal efficacy screening of Anacardaciae crude extracts on the dengue hemorrhagic vector, Aedes aegypti.

    Science.gov (United States)

    Zuharah, W F; Fadzly, N; Ali, Y; Zakaria, R; Juperi, S; Asyraf, M; Dieng, H

    2014-06-01

    Vector-borne diseases are still rife because of the re-emergence of diseases transmitted by mosquitoes. The objective of this paper is to evaluate the larvicidal efficacy of crude leaf extract of Mangifera indica, Gluta renghas, and Melanochyla fasciculiflora against vector of dengue hemorrhagic fever, Aedes aegypti. These plant species are endemic species and widely distributed in Malaysian forests. Leaves of Ma. indica, G. renghas and M. fascculiflora were collected from Teluk Bahang National Park, Penang Malaysia. Fractions of leaves were segregated, air-dried, powdered and extracted using Soxhlet with methanol. The solvent was removed by using rotary evaporator to obtain the crude extract. Using WHO standard larval bioassay test method, third instar larvae of Aedes aegypti were exposed to concentration ranging from 200- 4500 ppm of methanol extract for all plant species. Larval mortality was observed after 24 hours exposure. The highest susceptibility and toxicity was recorded by Mangifera indica with the lowest concentration at 800 ppm followed by M. fasciculiflora and G. renghas. This indicates that crude plant extract is very effective in killing Ae. aegypti mosquitoes. This finding may lead to new low cost alternative, environmentally friendly method for mosquito control programs. To our knowledge, this is the first report on larvicidal bioefficacy from endemic Malaysian plants. PMID:25134898

  17. Analisis Fakto - Faktor Densitas Larva Aedes aegypti dan Endimisitas Penyakit Demam Berdarah Dengue di Kabupaten Bulukumba, Sulawasi Selatan

    OpenAIRE

    Hasanuddin, ishak; Abbas; arsin, arsunan

    2008-01-01

    Penyakit Demam Berdarah Dengue (DBD) masih merupakan masalah kesehatan masyarakat di Indonesia. Upaya gerakan 3M, abatisasi dan fogging sudah dilakukan namun densitas Aedes aegypti masih tinggi dan daerah endemism akin meluas. Penelitian ini bertujuan untuk menganalisis faktor ??? faktor yang berhubungan dengan densitas larva A. aegypti dan endemisitas Penyakit Demam Berdarah Dengue. Desain penelitian ini menggunakan cross sectional study dan dilaksanakan di 4 kelurahan endemis di Kecamatan U...

  18. Field Efficacy of New Larvicide Products for Control of Multi-Resistant Aedes aegypti Populations in Martinique (French West Indies)

    OpenAIRE

    Marcombe, Sébastien; Darriet, Frédéric; Agnew, Philip; Etienne, Manuel; Yp-Tcha, Marie-Michelle; Yébakima, André; Corbel, Vincent

    2011-01-01

    World-wide dengue vector control is hampered by the spread of insecticide resistance in Aedes aegypti. We report the resistance status of a wild Ae. aegypti population from Martinique (Vauclin) to conventional larvicides (Bacillus thuringiensis var israeliensis [Bti] and temephos) and potential alternatives (spinosad, diflubenzuron, and pyriproxyfen). The efficacy and residual activity of these insecticides were evaluated under simulated and field conditions. The Vauclin strain exhibited a hi...

  19. Fitness evaluation of two Brazilian Aedes aegypti field populations with distinct levels of resistance to the organophosphate temephos

    OpenAIRE

    Thiago Affonso Belinato; Ademir Jesus Martins; Denise Valle

    2012-01-01

    In Brazil, decades of dengue vector control using organophosphates and pyrethroids have led to dissemination of resistance. Although these insecticides have been employed for decades against Aedes aegypti in the country, knowledge of the impact of temephos resistance on vector viability is limited. We evaluated several fitness parameters in two Brazilian Ae. aegypti populations, both classified as deltamethrin resistant but with distinct resistant ratios (RR) for temephos. The insecticide-sus...

  20. Expression Profile of Genes during Resistance Reversal in a Temephos Selected Strain of the Dengue Vector, Aedes aegypti

    OpenAIRE

    Clare Strode; Maria de Melo-Santos; Tereza Magalhães; Ana Araújo; Contancia Ayres

    2012-01-01

    BACKGROUND: The mosquito Aedes aegypti is one of the most important disease vectors because it transmits two major arboviruses, dengue and yellow fever, which cause significant global morbidity and mortality. Chemical insecticides form the cornerstone of vector control. The organophosphate temephos a larvicide recommended by WHO for controlling Ae. aegypti, however, resistance to this compound has been reported in many countries, including Brazil. METHODOLOGY/PRINCIPAL FINDINGS: The aim of th...

  1. The efficacy of a chitin synthesis inhibitor against field populations of organophosphate-resistant Aedes aegypti in Brazil

    OpenAIRE

    Nathalia Giglio Fontoura; Diogo Fernandes Bellinato; Denise Valle; José Bento Pereira Lima

    2012-01-01

    The mosquito Aedes aegypti is the main focus of dengue control campaigns. Because of widespread resistance against conventional chemical insecticides, chitin synthesis inhibitors (CSIs) are considered control alternatives. We evaluated the resistance status of four Brazilian Ae. aegypti populations to both the organophosphate temephos and the pyrethroid deltamethrin, which are used in Brazil to control larvae and adults, respectively. All vector populations exhibited high levels of temephos r...

  2. The susceptibility of Aedes aegypti populations displaying temephos resistance to Bacillus thuringiensis israelensis: a basis for management

    OpenAIRE

    Araújo, Ana Paula; Araujo Diniz, Diego Felipe; Helvecio, Elisama; de Barros, Rosineide Arruda; de Oliveira, Cláudia Maria Fontes; Ayres, Constância Flávia Junqueira; de Melo-Santos, Maria Alice Varjal; Regis, Lêda Narcisa; Silva-Filha, Maria Helena Neves Lobo

    2013-01-01

    Background Aedes aegypti is the vector of dengue virus, and its control is essential to prevent disease transmission. Among the agents available to control this species, biolarvicides based on Bacillus thuringiensis serovar israelensis (Bti) are an effective alternative to replace the organophosphate temephos for controlling populations that display resistance to this insecticide. The major goal of this study was to determine the baseline susceptibility of Brazilian Ae. aegypti populations to...

  3. Permethrin-treated clothing as protection against the Dengue vector, Aedes aegypti : extent and duration of protection.

    OpenAIRE

    Sarah DeRaedt Banks; James Orsborne; Salvador A. Gezan; Harparkash Kaur; Annelies Wilder-Smith; Lindsey, Steve W.; Logan, James G

    2015-01-01

    INTRODUCTION: Dengue transmission by the mosquito vector, Aedes aegypti, occurs indoors and outdoors during the day. Personal protection of individuals, particularly when outside, is challenging. Here we assess the efficacy and durability of different types of insecticide-treated clothing on laboratory-reared Ae. aegypti. METHODS: Standardised World Health Organisation Pesticide Evaluation Scheme (WHOPES) cone tests and arm-in-cage assays were used to assess knockdown (KD) and mortality of Ae...

  4. VECTOR RESISTANCE STATUS OF DENGUE HEMORRHAGIC FEVER (Aedes aegypti IN THE SIDOREJO DISTRICT SALATIGA CITY AGAINST TEMEPHOS (ORGANOPHOSPHATES

    Directory of Open Access Journals (Sweden)

    Ary Oktsari Yanti S

    2014-06-01

    Full Text Available One of the efforts to control the incidence of Dengue Hemorrhagic Fever (DHF is contrled thedengue vector larvae using larvasida. The most widely larvasida used to control larvae Ae.aegypti is temephos. In Indonesia 1% temephos (abate 1SG has been used since 1976, and since1980 has been used for the eradication program ofAe. aegypti larvae. The purpose of this studyis to determine the resistance status of vectors of dengue hemorrhagic fever (Ae. aegypti ofendemic, sporadic, and potentially in Sub District Sidorejo Salatiga City to temephos(organofosfat. This research was conducted using experimental research design (TrueExperiment, posttcst design with control groups (posttest-only Control Group Design. Thepopulation of the research were larvae of Ae. aegypti collected from the study area. Samples testlarvae were used of Ae. aegypti third and early fourth instars larvae which were maintenance ofthe first generation. The result showed that the mortality percentages of Ae. aegypti larvaeof endemic, sporadic and potential administratives against temephos using WHO standardconcentration (0,625; 0,125; 0,025 mg/1 indicates the mortality of Ae. aegypti larvae by 100%Based on the status resistance criteria, Ae. aegypti larvae from endemic, sporadic, and potentialadministratives of Sidorejo Sub-District, Salatiga City is still susceptible to temephos.Keywords : Status of resistance, Aedes aegypti. TemephosSalah satu upaya menurunkan Demam Berdarah Dengue (DBD adalah melaluipengcndalian jentik vektor DBD dengan larvasida. Larvasida yang digunakan untukmengcndalikan jentik Ae. aegypti adalah temephos. Temephos 1% (abate ISG sudah programdi Indonesia sejak 1976, scjak 1980 telah digunakan secara massal untuk programpemberantasan jentik Ae. aegypti. Tujuan penelitian ini adalah untuk mengetahui status resistensivektor demam berdarah dengue Ae. aegypti di kclurahan endemis, sporadis, dan potensialKecamatan Sidorejo Kota Salatiga terhadap temephos

  5. Aspectos bioecológicos de importancia para el control de Aedes aegypti y otros culicidos en el ecosistema urbano

    OpenAIRE

    Marquetti Fernández, María del Carmen

    2007-01-01

    Conocer la influencia del Programa de Erradicación de Aedes aegypti en la incidencia, y abundancia de culícidos incluyendo el vector del dengue en el ecosistema urbano es de importancia ya que las enfermedades transmitidas por estos constituyen problemas prioritarios de salud en Cuba. El presente trabajo aporta conocimientos novedosos con relación a la bioecologia de Aedes aegypti y otros culícidos, como Culex quinquefasciatus y Gymnometopa mediovittata, así como la caracterización de los háb...

  6. Embryonic desiccation resistance in Aedes aegypti: presumptive role of the chitinized Serosal Cuticle

    Directory of Open Access Journals (Sweden)

    Peixoto Alexandre

    2008-09-01

    Full Text Available Abstract Background One of the major problems concerning dengue transmission is that embryos of its main vector, the mosquito Aedes aegypti, resist desiccation, surviving several months under dry conditions. The serosal cuticle (SC contributes to mosquito egg desiccation resistance, but the kinetics of SC secretion during embryogenesis is unknown. It has been argued that mosquito SC contains chitin as one of its components, however conclusive evidence is still missing. Results We observed an abrupt acquisition of desiccation resistance during Ae. aegypti embryogenesis associated with serosal cuticle secretion, occurring at complete germ band extension, between 11 and 13 hours after egglaying. After SC formation embryos are viable on dry for at least several days. The presence of chitin as one of the SC constituents was confirmed through Calcofluor and WGA labeling and chitin quantitation. The Ae. aegypti Chitin Synthase A gene (AaCHS1 possesses two alternatively spliced variants, AaCHS1a and AaCHS1b, differentially expressed during Ae. aegypti embryonic development. It was verified that at the moment of serosal cuticle formation, AaCHS1a is the sole variant specifically expressed. Conclusion In addition to the peritrophic matrix and exoskeleton, these findings confirm chitin is also present in the mosquito serosal cuticle. They also point to the role of the chitinized SC in the desiccation resistance of Ae. aegypti eggs. AaCHS1a expression would be responsible for SC chitin synthesis. With this embryological approach we expect to shed new light regarding this important physiological process related to the Ae. aegypti life cycle.

  7. Human-Mediated Marine Dispersal Influences the Population Structure of Aedes aegypti in the Philippine Archipelago.

    Directory of Open Access Journals (Sweden)

    Eugenio Fonzi

    Full Text Available Dengue virus (DENV is an extraordinary health burden on global scale, but still lacks effective vaccine. The Philippines is endemic for dengue fever, but massive employment of insecticides favored the development of resistance mutations in its major vector, Aedes aegypti. Alternative vector control strategies consist in releasing artificially modified mosquitos in the wild, but knowledge on their dispersal ability is necessary for a successful implementation. Despite being documented that Ae. aegypti can be passively transported for long distances, no study to date has been aimed at understanding whether human marine transportation can substantially shape the migration patterns of this mosquito. With thousands of islands connected by a dense network of ships, the Philippines is an ideal environment to fill this knowledge gap.Larvae of Ae. aegypti from 15 seaports in seven major islands of central-western Philippines were collected and genotyped at seven microsatellite loci. Low genetic structure and considerable gene flow was found in the area. Univariate and multivariate regression analyses suggested that anthropic factors (specifically the amount of processed cargo and human population density can explain the observed population structure, while geographical distance was not correlated. Interestingly, cargo shipments seem to be more efficient than passenger ships in transporting Ae. aegypti. Bayesian clustering confirmed that Ae. aegypti from busy ports are more genetically similar, while populations from idle ports are relatively structured, regardless of the geographical distance that separates them.The results confirmed the pivotal role of marine human-mediated long-range dispersal in determining the population structure of Ae. aegypti. Hopefully corroborated by further research, the present findings could assist the design of more effective vector control strategies.

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

    Directory of Open Access Journals (Sweden)

    Hortance Manda

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

  9. Chemical constituents of the stems of Spathelia excelsa (rutaceae) and activity against Aedes aegypti; Constituintes quimicos do caule de Spathelia excelsa (rutaceae) e atividade contra Aedes aegypti

    Energy Technology Data Exchange (ETDEWEB)

    Freitas, Aline Carvalho de; Lima, Maria da Paz [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Coordenacao de Pesquisas em Produtos Naturais], e-mail: mdapaz@inpa.gov.br; Ferreira, Antonio Gilberto [Universidade Federal de Sao Carlos (UFSCAR), SP (Brazil). Dept. de Quimica; Tadei, Wanderli Pedro; Pinto, Ana Cristina da Silva [Instituto Nacional de Pesquisas da Amazonia (INPA), Manaus, AM (Brazil). Lab. de Vetores de Malaria e Dengue

    2009-07-01

    Phytochemical investigation from the stems of Spathelia excelsa (Rutaceae) collected in Amazonas yielded deacetylspathelin (1), 7,8-dimethoxyflindersine (2), new glabretal-type triterpenoid 3{beta}-angeloyl-21,24-epoxy-7{alpha}, 21{alpha}, 23{alpha}, 25-tetrahydroxy-4{alpha}, 4{beta}, 8{beta}, 10{beta}-tetramethyl-25-dimethyl-14,18-cyclo-5{alpha}, 13{alpha}, 14{alpha}, 17{alpha}-cholestane (3), in addition to the known steroids s-sitosterol and stigmasterol. Their structures were established on the basis of spectral data. The compounds 1 and 3 were assayed on Aedes aegypti (larvicidal and adulticidal activities and compound 3 exhibited larvicidal properties with LC{sub 50} of 4,8 {mu}g/mL. (author)

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

    Directory of Open Access Journals (Sweden)

    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

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

    Directory of Open Access Journals (Sweden)

    Calheiros Cláudia ML

    1998-01-01

    Full Text Available A study was conducted to determine the susceptibility of local strains of Culex quinquefasciatus and Aedes aegypti to infection with the strain of Wuchereria bancrofti that occurs in Maceió, State of Alagoas, Brazil. Cx. quinquefasciatus blood fed simultaneously on the same microfilariae carrier ingested more blood and 2-3x more microfilariae than Ae. aegypti. Survival rates of both species of insects living for 21 days after blood feeding on microfilaraemic patients were not significantly different from the survival rates of mosquitoes that blood fed on amicrofilaraemic individuals. W. bancrofti parasites underwent normal development in Cx. quinquefasciatus, with third stage larvae first being recorded on the 11th day post infection, and their numbers increasing thereafter. Development of filariae in Ae. aegypti did not proceed beyond the first larval stage, and there was a progressively increasing number of non-viable larvae with the passage of time. It is concluded that Ae. aegypti is not involved in the transmission of W. bancrofti in Maceió.

  12. TALEN-based gene disruption in the dengue vector Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Azadeh Aryan

    Full Text Available In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20-40% of fertile survivors produced kmo alleles that failed to complement an existing kh(w mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1-7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector.

  13. Semaphorin-1a is required for Aedes aegypti embryonic nerve cord development.

    Directory of Open Access Journals (Sweden)

    Morgan Haugen

    Full Text Available Although mosquito genome projects have uncovered orthologues of many known developmental regulatory genes, extremely little is known about mosquito development. In this study, the role of semaphorin-1a (sema1a was investigated during vector mosquito embryonic ventral nerve cord development. Expression of sema1a and the plexin A (plexA receptor are detected in the embryonic ventral nerve cords of Aedes aegypti (dengue vector and Anopheles gambiae (malaria vector, suggesting that Sema1a signaling may regulate mosquito nervous system development. Analysis of sema1a function was investigated through siRNA-mediated knockdown in A. aegypti embryos. Knockdown of sema1a during A. aegypti development results in a number of nerve cord phenotypes, including thinning, breakage, and occasional fusion of the longitudinal connectives, thin or absent commissures, and general distortion of the nerve cord. Although analysis of Drosophila melanogaster sema1a loss-of-function mutants uncovered many similar phenotypes, aspects of the longitudinal phenotypes differed between D. melanogaster and A. aegypti. The results of this investigation suggest that Sema1a is required for development of the insect ventral nerve cord, but that the developmental roles of this guidance molecule have diverged in dipteran insects.

  14. STUDIES ON AEDES AEGYPTI RESISTANCE TO SOME INSECTICIDES IN THE JAZAN DISTRICT, SAUDI ARABIA.

    Science.gov (United States)

    Alsheikh, Adel A; Mohammed, W S; Noureldin, E M; Daffalla, O M; Shrwani, Y A; Hobani, K J; Alsheikh, F A; Alzahrani, M H; Binsaeed, A A

    2016-04-01

    The present study provided information on the susceptibility status of the adult and larvae of Aedes aegypti mosquitoes in Jazan region of Saudi Arabia. Bioassay tests were performed on adults and larvae by using WHO recommended concentrations and test kits. Adults of Ae. aegypti mosquitoes were exposed to test papers impregnated with Lambda-cyhalothrin (0.05%), Cyfluthrin (0.15%), Deltamethrin (0.05%), Permethrin (0.75%), Fenitrothion (1%), Bendiocarb (0.1%) and DDT (4%) insecticides. Ae. aegypti mosquitoes were found to be susceptible only to Cyfluthrin; (mortality rate was 100%), whereas variable resistances were observed from the rest of the other insecticides tested (mortality rates ranged between 93.6 and 17%). Larvae were subjected to different concentrations of Diflubenzuron, Methoprene (IGRs) and Temephos (Organophosphate). Adult emergence inhibition (IE₅₀ & IE₉₅) values for the IGRs and the (LC₅₀ & LC₉₅) for Temephos were determined by log-probit regression analysis. Ae. aegypti larvae were resistant to Temephos (LC₅₀ 61.8-LC₉₅ 35600.1 mg/l) and showed high susceptibility to Methoprene than Diflubenzuron (IE₅₀ 0.49-IE₉₅ 10.9 mg/l) and (IE₅₀ 0.86 and IE₉₅ 93.8 mg/l), respectively. Larvae were more susceptible to Methoprene than Diflubenzuron by 1.8 folds.

  15. Toxicity of Cephalaria Species and their Individual Constituents against Aedes aegypti.

    Science.gov (United States)

    Sarikahya, Nazli Boke; Kayce, Peyker; Tabanca, Nurhayat; Estep, Alden S; Becnel, James J; Khan, Ikhlas A; Kirmizigul, Suheyla

    2015-07-01

    Crude acetone and ethanol extracts of the aerial parts of 21 Cephalaria species collected from Turkey were investigated for larvicidal and adult topical activity against Aedes aegypti. The ethanol extracts from C. elazigensis var. purpurea, C. anatolica, and C. elmaliensis possessed the highest mortality against first instar Ae. aegypti larvae. Luteolin-7-O-β-D-glycoside (1), isolated from C. elmaliensis ethanol extract, demonstrated 33% and 53% mortality at 0.1 μg/mL concentration against first instar ORL (susceptible) and PR (pyrethroid resistant) strains, respectively. C. scoparia acetone extract showed 100% mortality against adult Ae. aegypti. From this extract compounds 2-8 were isolated. Compound 2 (isoorientin) possessed the highest toxicity with 31.7% and 65% mortality at a 10 μg/mL concentration against adult ORL and PR strains, respectively. This is the first screening report of potential insecticides from Cephalaria species against the yellow fever mosquito, Ae. aegypti, and the active compounds (1 and 2) could lead to the development of a new class of insecticide.

  16. Toxicity of Cephalaria Species and their Individual Constituents against Aedes aegypti.

    Science.gov (United States)

    Sarikahya, Nazli Boke; Kayce, Peyker; Tabanca, Nurhayat; Estep, Alden S; Becnel, James J; Khan, Ikhlas A; Kirmizigul, Suheyla

    2015-07-01

    Crude acetone and ethanol extracts of the aerial parts of 21 Cephalaria species collected from Turkey were investigated for larvicidal and adult topical activity against Aedes aegypti. The ethanol extracts from C. elazigensis var. purpurea, C. anatolica, and C. elmaliensis possessed the highest mortality against first instar Ae. aegypti larvae. Luteolin-7-O-β-D-glycoside (1), isolated from C. elmaliensis ethanol extract, demonstrated 33% and 53% mortality at 0.1 μg/mL concentration against first instar ORL (susceptible) and PR (pyrethroid resistant) strains, respectively. C. scoparia acetone extract showed 100% mortality against adult Ae. aegypti. From this extract compounds 2-8 were isolated. Compound 2 (isoorientin) possessed the highest toxicity with 31.7% and 65% mortality at a 10 μg/mL concentration against adult ORL and PR strains, respectively. This is the first screening report of potential insecticides from Cephalaria species against the yellow fever mosquito, Ae. aegypti, and the active compounds (1 and 2) could lead to the development of a new class of insecticide. PMID:26411009

  17. STUDIES ON AEDES AEGYPTI RESISTANCE TO SOME INSECTICIDES IN THE JAZAN DISTRICT, SAUDI ARABIA.

    Science.gov (United States)

    Alsheikh, Adel A; Mohammed, W S; Noureldin, E M; Daffalla, O M; Shrwani, Y A; Hobani, K J; Alsheikh, F A; Alzahrani, M H; Binsaeed, A A

    2016-04-01

    The present study provided information on the susceptibility status of the adult and larvae of Aedes aegypti mosquitoes in Jazan region of Saudi Arabia. Bioassay tests were performed on adults and larvae by using WHO recommended concentrations and test kits. Adults of Ae. aegypti mosquitoes were exposed to test papers impregnated with Lambda-cyhalothrin (0.05%), Cyfluthrin (0.15%), Deltamethrin (0.05%), Permethrin (0.75%), Fenitrothion (1%), Bendiocarb (0.1%) and DDT (4%) insecticides. Ae. aegypti mosquitoes were found to be susceptible only to Cyfluthrin; (mortality rate was 100%), whereas variable resistances were observed from the rest of the other insecticides tested (mortality rates ranged between 93.6 and 17%). Larvae were subjected to different concentrations of Diflubenzuron, Methoprene (IGRs) and Temephos (Organophosphate). Adult emergence inhibition (IE₅₀ & IE₉₅) values for the IGRs and the (LC₅₀ & LC₉₅) for Temephos were determined by log-probit regression analysis. Ae. aegypti larvae were resistant to Temephos (LC₅₀ 61.8-LC₉₅ 35600.1 mg/l) and showed high susceptibility to Methoprene than Diflubenzuron (IE₅₀ 0.49-IE₉₅ 10.9 mg/l) and (IE₅₀ 0.86 and IE₉₅ 93.8 mg/l), respectively. Larvae were more susceptible to Methoprene than Diflubenzuron by 1.8 folds. PMID:27363057

  18. 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.

  19. Agave sisalana extract induces cell death in Aedes aegypti hemocytes increasing nitric oxide production

    Institute of Scientific and Technical Information of China (English)

    Fabrine Felipe Hilario; Gabriel Joventino Nascimento; Joo Paulo Saraiva Morais; Everaldo Paulo de Medeiros; Manoel Francisco de Sousa; Fabiola da Cruz Nunes

    2016-01-01

    Objective: To investigate the effects of Agave sisalana (A. sisalana) extract on Aedes aegypti (Ae. aegypti) primary cell culture. Methods: Cells of Ae. aegypti were exposed to different concentrations of A. sisalana crude extract (0.18–6.00 mg/mL) for 24 h. Then, the cells were labeled with propidium iodide and subjected to fluorescence microscopy to verify cell viability. In addition, nitric oxide production was measured. Results: Results showed that cells exposed to 6 mg/mL of the crude extract presented a greater percentage of death when compared to control (73.8%± 9.6%vs. 34.6%± 9.6%). Furthermore, there was an increase in the nitric oxide production in cells exposed to 6 mg/mL of A. sisalana crude extract [(0.81 ± 0.08) mmol/L] compared to control group [(0.41 ± 0.18) mmol/L]. Conclusions: The results show that A. sisalana is cytotoxic to Ae. aegypti and may be used as raw material for new eco-friendly and inexpensive insecticides, since sisal in-dustry discards the liquid waste for the extraction of plant fiber.

  20. Complement-related proteins control the flavivirus infection of Aedes aegypti by inducing antimicrobial peptides.

    Directory of Open Access Journals (Sweden)

    Xiaoping Xiao

    2014-04-01

    Full Text Available The complement system functions during the early phase of infection and directly mediates pathogen elimination. The recent identification of complement-like factors in arthropods indicates that this system shares common ancestry in vertebrates and invertebrates as an immune defense mechanism. Thioester (TE-containing proteins (TEPs, which show high similarity to mammalian complement C3, are thought to play a key role in innate immunity in arthropods. Herein, we report that a viral recognition cascade composed of two complement-related proteins limits the flaviviral infection of Aedes aegypti. An A. aegypti macroglobulin complement-related factor (AaMCR, belonging to the insect TEP family, is a crucial effector in opposing the flaviviral infection of A. aegypti. However, AaMCR does not directly interact with DENV, and its antiviral effect requires an A. aegypti homologue of scavenger receptor-C (AaSR-C, which interacts with DENV and AaMCR simultaneously in vitro and in vivo. Furthermore, recognition of DENV by the AaSR-C/AaMCR axis regulates the expression of antimicrobial peptides (AMPs, which exerts potent anti-DENV activity. Our results both demonstrate the existence of a viral recognition pathway that controls the flaviviral infection by inducing AMPs and offer insights into a previously unappreciated antiviral function of the complement-like system in arthropods.

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

    Science.gov (United States)

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

    2006-12-01

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

  2. Immunotoxicity activity of sesquiterpenoids from black galingale (Kaempferia parviflora Wall. Ex. Baker) against Aedes aegypti L.

    Science.gov (United States)

    Moon, Hyung-In; Cho, Sang-Buem; Lee, Jun-Hyeong; Paik, Hyun-Dong; Kim, Soo-Ki

    2011-06-01

    The roots of black galingale (Kaempferia parviflora) were chloroform-extracted and the isolated two sesquiterpene and immunotoxicity effects were studied. The structures and stereochemistry of these compounds were established on the basis of analysis of spectra including UV, MS, (1)H-NMR, and (13)C-NMR as follows: 1 (4α-acetoxycadina-2,9-diene-1,8-dione), 2 (1α,3α,4β-trihydroxy-9-cadinen-8-one). Compound 2 had a significant toxic effect against early fourth-stage larvae of Aedes aegypti L. with an LC(50) value of 0.7 μM and an LC(90) value of 3.8 μM. The results could be useful in search for newer, safer, and more effective natural immunotoxicity agents against A. aegypti. PMID:20925462

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

    Directory of Open Access Journals (Sweden)

    Mathieu Legros

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

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

    Directory of Open Access Journals (Sweden)

    Filipe Vieira Santos de Abreu

    2015-08-01

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

  5. Effect of Wolbachia on insecticide susceptibility in lines of Aedes aegypti.

    Science.gov (United States)

    Endersby, N M; Hoffmann, A A

    2013-06-01

    Two stable infections of Wolbachia pipientis, wMelPop and wMel, now established in Aedes aegypti, are being used in a biocontrol program to suppress the transmission of dengue. Any effects of Wolbachia infection on insecticide resistance of mosquitoes may undermine the success of this program. Bioassays of Ae. aegypti were conducted to test for differences in response to insecticides between Wolbachia infected (wMelPop, wMel) and uninfected lines. Insecticides screened were bifenthrin, the pyrethroid commonly used for adult knockdown, as well as larvicides: Bacillus thuringiensis var. israelensis, the organophosphate, temephos and the insect growth regulator, s-methoprene. While differences in response between lines were detected for some insecticides, no obvious or consistent effects related to presence of Wolbachia infection were observed. Spreading Wolbachia infections are, therefore, unlikely to affect the efficacy of traditional chemical control of mosquito outbreaks. PMID:23149015

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

    Science.gov (United States)

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

    2015-01-01

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

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

    Science.gov (United States)

    Viana-Medeiros, Priscila Fernandes; Araújo, Simone Costa; Martins, Ademir J.; Lima, José Bento Pereira

    2016-01-01

    Insecticides are still largely applied in public health to control disease vectors. In Brazil, organophosphates (OP) and pyrethroids (PY) are used against Aedes aegypti for years. Since 2009 Insect Growth Regulators (IGR) are also employed in the control of larvae. We quantified resistance to temephos (OP), deltamethrin (PY), and diflubenzuron (IGR) of A. aegypti samples from 12 municipalities distributed throughout the country, collected between 2010 and 2012. High levels of resistance to neurotoxic insecticides were detected in almost all populations: RR95 to temephos varied between 4.0 and 27.1; the lowest RR95 to deltamethrin was 13.1, and values higher than 70.0 were found. In contrast, all samples were susceptible to diflubenzuron (RR95 insecticides during dengue epidemic seasons in the evaluated municipalities. PMID:27419140

  8. HPTLC analysis of Scoparia dulcis Linn (Scrophulariaceae) and its larvicidal potential against dengue vector Aedes aegypti.

    Science.gov (United States)

    Wankhar, Wankupar; Srinivasan, Sakthivel; Rathinasamy, Sheeladevi

    2015-01-01

    This study evaluates the larvicidal activity of Scoparia dulcis aqueous extract against dengue vector and determines its major chemical components. The extract was tested at various concentrations ranging from 0.1 to 2 mg/mL against Aedes aegypti larvae. The extracts displayed significant larvicidal efficacy against Ae. aegypt species after 24 h exposure revealing LC50 of 3.3835 (mg/mL) and LC90 of 5.7578 (mg/mL). Finger printing profile carried out by CAMAG automatic TLC sample applicator programmed through WIN CATS software revealed peaks with different Rf values for three different volumes injected: 16, 15 and 18 peaks were spotted for 3, 6 and 9 μL, respectively. Ascending order of Rf values was also ascertained for each peak recorded. This study clearly signifies that S. dulcis extract contains numerous compounds that are known to have larvicidal properties which clearly substantiates its efficacy on Ae. aegypti larvae. PMID:25573588

  9. Dual African origins of global Aedes aegypti s.l. populations revealed by mitochondrial DNA.

    Directory of Open Access Journals (Sweden)

    Michelle Moore

    Full Text Available BACKGROUND: Aedes aegypti is the primary global vector to humans of yellow fever and dengue flaviviruses. Over the past 50 years, many population genetic studies have documented large genetic differences among global populations of this species. These studies initially used morphological polymorphisms, followed later by allozymes, and most recently various molecular genetic markers including microsatellites and mitochondrial markers. In particular, since 2000, fourteen publications and four unpublished datasets have used sequence data from the NADH dehydrogenase subunit 4 mitochondrial gene to compare Ae. aegypti collections and collectively 95 unique mtDNA haplotypes have been found. Phylogenetic analyses in these many studies consistently resolved two clades but no comprehensive study of mtDNA haplotypes have been made in Africa, the continent in which the species originated. METHODS AND FINDINGS: ND4 haplotypes were sequenced in 426 Ae. aegypti s.l. from Senegal, West Africa and Kenya, East Africa. In Senegal 15 and in Kenya 7 new haplotypes were discovered. When added to the 95 published haplotypes and including 6 African Aedes species as outgroups, phylogenetic analyses showed that all but one Senegal haplotype occurred in a basal clade while most East African haplotypes occurred in a second clade arising from the basal clade. Globally distributed haplotypes occurred in both clades demonstrating that populations outside Africa consist of mixtures of mosquitoes from both clades. CONCLUSIONS: Populations of Ae. aegypti outside Africa consist of mosquitoes arising from one of two ancestral clades. One clade is basal and primarily associated with West Africa while the second arises from the first and contains primarily mosquitoes from East Africa.

  10. SEASONAL ABUNDANCE OF ADULT AND IMMATURE AEDES AEGYPTI (L.) IN JAKARTA

    OpenAIRE

    M. J. Nelson; Salim Usman; C. P. Pant; Self, L. S.

    2012-01-01

    Dari bulan Mei 1973 sampai bulan Juni 1974 telah dilakukan pengamatan nyamuk Aedes aegypti stadium dewasa dan larva di keempat daerah kota yang berpenduduk padat di Jakarta Raya. Pengamatan dikerjakan 2 kali dalam satu bulan Daya tarik nyamuk terhadap manusia rata-rata 1.2 induk betina dan 1.6 untuk nyamuk jantan tiap orang tiap jam. Dalam 100 rumah diketemukan rata-rata 180 buah bejana berisi air, dimana 58 buah positif; Container index (persentasi bejana yang tositif) 32 persen House index ...

  11. 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 ...

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

    Directory of Open Access Journals (Sweden)

    Jackson Nunes e Vasconcelos

    2012-01-01

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

  13. Promising Aedes aegypti repellent chemotypes identified through integrated QSAR, virtual screening, synthesis, and bioassay.

    Science.gov (United States)

    Oliferenko, Polina V; Oliferenko, Alexander A; Poda, Gennadiy I; Osolodkin, Dmitry I; Pillai, Girinath G; Bernier, Ulrich R; Tsikolia, Maia; Agramonte, Natasha M; Clark, Gary G; Linthicum, Kenneth J; Katritzky, Alan R

    2013-01-01

    Molecular field topology analysis, scaffold hopping, and molecular docking were used as complementary computational tools for the design of repellents for Aedes aegypti, the insect vector for yellow fever, chikungunya, and dengue fever. A large number of analogues were evaluated by virtual screening with Glide molecular docking software. This produced several dozen hits that were either synthesized or procured from commercial sources. Analysis of these compounds by a repellent bioassay resulted in a few highly active chemicals (in terms of minimum effective dosage) as viable candidates for further hit-to-lead and lead optimization effort.

  14. Efeito residual de temephós em larvas de Aedes aegypti

    OpenAIRE

    Maria de Lourdes G Macoris; Maria Teresa M Andrighetti; Luiz Takaku

    1995-01-01

    Uma das estratégias de controle do Aedes aegypti é o uso do larvicida temephós, cujo efeito residual prolongado permite a programação de tratamentos focais. O objetivo deste estudo é verificar a duração do efeito residual do temephós simulando-se uma situação de campo. Recipientes plásticos com capacidade de um e cinco litros, foram tratados com temephós e seu efeito residual testado a cada trinta dias. Foram observadas diferentes durações do efeito residual, o qual foi maior nos recipientes ...

  15. Optimization of the Aedes aegypti Control Strategies for Integrated Vector Management

    Directory of Open Access Journals (Sweden)

    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.

  16. Comportamento de formas imaturas de Aedes aegypti, no litoral do Estado de São Paulo

    Directory of Open Access Journals (Sweden)

    Carmen Moreno Glasser

    2011-06-01

    Full Text Available INTRODUÇÃO: Em região de alta incidência de dengue, no litoral do Estado de São Paulo, selecionaram-se 9 áreas, com objetivo de avaliar o comportamento de formas imaturas de Aedes aegypti. MÉTODOS: As 9 áreas foram agrupadas em 4 estratos, diferenciados pelo uso e ocupação do solo. Foram coletadas larvas e pupas numa amostra de cerca de 500 imóveis em cada área. RESULTADOS: Apesar do pneu e lona apresentarem as maiores taxas de positividade para Aedes aegypti, o ralo, juntamente com outros recipientes fixos nas edificações foram altamente predominantes entre os recipientes positivos (32 a 76% dos recipientes positivos. As áreas coletivas de prédios e os imóveis não residenciais de grande porte apresentaram as maiores taxas de positividade para Aedes aegypti enquanto os apartamentos, as menores. Os níveis de infestação foram maiores na área residencial com predominância de prédios de apartamentos, onde 76% dos criadouros detectados foram recipientes fixos nas edificações. CONCLUSÕES: Esses conhecimentos são importantes subsídios para a estratégia de controle, pois reforçam a necessidade de atenção especial para determinados tipos de imóveis, bem como da adequação da norma técnica de ralo de água pluvial e da melhoria de manutenção das edificações. Além disso, são necessárias observações sistemáticas que permitam acompanhar a dinâmica de ocupação de diferentes imóveis e recipientes por Aedes aegypti e a incorporação desses conhecimentos nas ações de controle do vetor na região.

  17. Seasonal Differences in Density But Similar Competitive Impact of Aedes albopictus (Skuse) on Aedes aegypti (L.) in Rio de Janeiro, Brazil

    Science.gov (United States)

    Camara, Daniel Cardoso Portela; Codeço, Claudia Torres; Juliano, Steven A.; Lounibos, L. Philip; Riback, Thais Irene Souza; Pereira, Glaucio Rocha; Honorio, Nildimar Alves

    2016-01-01

    Previous studies have shown that the negative effects of density of Ae. albopictus on Ae. aegypti exceed those of Ae. aegypti on Ae. albopictus for population growth, adult size, survivorship, and developmental rate. This competitive superiority has been invoked to explain the displacement of Ae. aegypti by Ae. albopictus in the southeastern USA. In Brazil, these species coexist in many vegetated suburban and rural areas. We investigated a related, but less-well-studied question: do effects of Ae. albopictus on Ae. aegypti larval development and survival occur under field conditions at realistic densities across multiple seasons in Brazil? We conducted additive competition experiments in a vegetated area of Rio de Janeiro where these species coexist. We tested the hypothesis that Ae. aegypti (the focal species, at a fixed density) suffers negative effects on development and survivorship across a gradient of increasing densities of Ae. albopictus (the associate species) in three seasons. The results showed statistically significant effects of both season and larval density on Ae. aegypti survivorship, and significant effects of season on development rate, with no significant season-density interactions. Densities of Aedes larvae in these habitats differed among seasons by a factor of up to 7x. Overall, Spring was the most favorable season for Ae. aegypti survivorship and development. Results showed that under natural conditions the negative competitive effects of Ae. albopictus on Ae. aegypti were expressed primarily as lower survivorship. Coexistence between Ae. aegypti and Ae. albopictus in vegetated areas is likely affected by seasonal environmental differences, such as detrital resource levels or egg desiccation, which can influence competition between these species. Interactions between these Aedes are important in Brazil, where both species are well established and widely distributed and vector dengue, Zika and chikungunya viruses. PMID:27322537

  18. Seasonal Differences in Density But Similar Competitive Impact of Aedes albopictus (Skuse on Aedes aegypti (L. in Rio de Janeiro, Brazil.

    Directory of Open Access Journals (Sweden)

    Daniel Cardoso Portela Camara

    Full Text Available Previous studies have shown that the negative effects of density of Ae. albopictus on Ae. aegypti exceed those of Ae. aegypti on Ae. albopictus for population growth, adult size, survivorship, and developmental rate. This competitive superiority has been invoked to explain the displacement of Ae. aegypti by Ae. albopictus in the southeastern USA. In Brazil, these species coexist in many vegetated suburban and rural areas. We investigated a related, but less-well-studied question: do effects of Ae. albopictus on Ae. aegypti larval development and survival occur under field conditions at realistic densities across multiple seasons in Brazil? We conducted additive competition experiments in a vegetated area of Rio de Janeiro where these species coexist. We tested the hypothesis that Ae. aegypti (the focal species, at a fixed density suffers negative effects on development and survivorship across a gradient of increasing densities of Ae. albopictus (the associate species in three seasons. The results showed statistically significant effects of both season and larval density on Ae. aegypti survivorship, and significant effects of season on development rate, with no significant season-density interactions. Densities of Aedes larvae in these habitats differed among seasons by a factor of up to 7x. Overall, Spring was the most favorable season for Ae. aegypti survivorship and development. Results showed that under natural conditions the negative competitive effects of Ae. albopictus on Ae. aegypti were expressed primarily as lower survivorship. Coexistence between Ae. aegypti and Ae. albopictus in vegetated areas is likely affected by seasonal environmental differences, such as detrital resource levels or egg desiccation, which can influence competition between these species. Interactions between these Aedes are important in Brazil, where both species are well established and widely distributed and vector dengue, Zika and chikungunya viruses.

  19. Evaluación del efecto residual del Temephos en larvas de Aedes aegypti en Lima, Perú

    OpenAIRE

    Miriam Palomino S; Lely Solari; Walter León C; Rosario Vega H; Máximo Vergaray C; Luis Cubillas; Rosa Mosqueda C; Norma García A

    2006-01-01

    El temephos ha sido usado como la única estrategia de control para Aedes aegypti en Lima durante los últimos años. Objetivo: Evaluar la eficacia residual de temephos para el control de Ae. aegypti en condiciones de campo y laboratorio en Lima, Perú. Materiales y métodos: Se eligieron ocho tanques bajos de concreto (TBC) depósitos predominantemente infestados con Ae. aegypti en el distrito de San Juan de Lurigancho, situado al norte del área suburbana de Lima. Se cuantificó el número de larvas...

  20. Isolation and selection of local isolates of chitinolitic bacteria that potent to biocontrol of larva stadia of Aedes aegypti L.

    Directory of Open Access Journals (Sweden)

    SRI PUJIYANTO

    2008-01-01

    Full Text Available The dengue fever was the most dangerously epidemic in Indonesia, so it is important to prevent the population of Aedes aegypti L. The larva stages of Ae. aegypti had an exosceleton from chitin, so if its exosceleton had been degraded the larva would be died. Many bacteria had chitin degradation activities, and the bacteria had potential as a biocontrol for Ae. aegypti larva stages. This research was got many of the local chitinolitic bacteria that had been potential as a biocontrol for Ae. aegypti larva stages. The chitinolitic bacteria were isolated with selective agar medium. The sources of isolates were collected from Central Java and West Java water resources. Selected isolates was done to get the higher chitinolitic activity in mineral water medium. The isolate LMB1-5 was potential as a bioinsecticide for Ae. aegypti larva stages. This isolate decreased 86.7% of the larva population in 7 days.

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

    Directory of Open Access Journals (Sweden)

    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

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

    Science.gov (United States)

    Rey, Jorge R; O'Connell, Sheila M

    2014-06-01

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

  3. 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

  4. Spatial Patterns of High Aedes aegypti Oviposition Activity in Northwestern Argentina

    Science.gov (United States)

    Estallo, Elizabet Lilia; Más, Guillermo; Vergara-Cid, Carolina; Lanfri, Mario Alberto; Ludueña-Almeida, Francisco; Scavuzzo, Carlos Marcelo; Introini, María Virginia; Zaidenberg, Mario; Almirón, Walter Ricardo

    2013-01-01

    Background In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. Methodology Oviposition activity was detected in Orán City (Salta province) using ovitraps, weekly replaced (October 2005–2007). Spatial autocorrelation was measured with Moran’s Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR) sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. Principal Findings Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC = 0.77), obtaining 99% of sensitivity and 75.29% of specificity. Conclusions Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist National Health

  5. Evaluation of herbal essential oil as repellents against Aedes aegypti (L.) and Anopheles dirus Peyton & Harrion

    Institute of Scientific and Technical Information of China (English)

    Duangkamon Sritabutra; Mayura Soonwera; Sirirat Waltanachanobon; Supaporn Poungjai

    2011-01-01

    Objective: To investigate the repellent activity of herbal essential oils from garlic (Allium sativum), clove (Syzygium aromaticum), lemon grass (Cybopogon citratus), citronella grass (Cymbopogon nardus), peppermint (Mentha piperita), eucalyptus (Eucalyptus globulus), orange (Citrus sinensis) and sweet basil (Ocimum basilicum) and their combinations against Aedes aegypti (Ae. aegypti) (L.) and Anopheles dirus (An. dirus) Peyton & Harrion under laboratory conditions.Methods:In laboratory condition, 0.1 mL of each essential oil was applied to 3-10 cm of exposed area on a volunteer’s forearm. The test was carried out every 30 min until fewer than two mosquitoes bit or land during the 3 min study period and then the repellency test was stopped.Results:Essential oil from lemon grass exhibited protection against biting from two mosquito species, for Ae. aegypti [(98.66±11.56) min protection time and 0.97% biting rate] and for An. dirus [(98.00±15.28) min protection time and 0.80% biting rate]. The combinations from eucalyptus oil and sweet basil oil were effective as repellents and feeding deterrents against Ae. aegypti [(98.87±10.28) min protection time and 0.90% biting rate] and An. dirus [(210±10.70) min protection time and 0.93% biting rate]. All herbal repellents exhibited the period of protection time against Ae. aegypti which was lower than 120 min. Conlussions: It can be concluded that oils of lemon grass and combination from eucalyptus-sweet basil are the most effective in repellent activity.

  6. The wMel Strain of Wolbachia Reduces Transmission of Chikungunya Virus in Aedes aegypti.

    Directory of Open Access Journals (Sweden)

    Matthew T Aliota

    2016-04-01

    Full Text Available New approaches to preventing chikungunya virus (CHIKV are needed because current methods are limited to controlling mosquito populations, and they have not prevented the invasion of this virus into new locales, nor have they been sufficient to control the virus upon arrival. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against CHIKV. Although this approach holds much promise for limiting virus transmission, at present our understanding of the ability of CHIKV to infect, disseminate, and be transmitted by wMel-infected Ae. aegypti currently being used at Wolbachia release sites is limited.Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for CHIKV, even with extremely high viral titers in the bloodmeal. In addition, we examined the dynamics of CHIKV infection over the course of four to seven days post feeding. Wolbachia-infected mosquitoes remained non-infective over the duration of seven days, i.e., no infectious virus was detected in the saliva when exposed to bloodmeals of moderate viremia, but CHIKV-exposed, wild type mosquitoes did have viral loads in the saliva consistent with what has been reported elsewhere. Finally, the presence of wMel infection had no impact on the lifespan of mosquitoes as compared to wild type mosquitoes following CHIKV infection.These results could have an impact on vector control strategies in areas where Ae. aegypti are transmitting both DENV and CHIKV; i.e., they argue for further exploration, both in the laboratory and the field, on the feasibility of expanding this technology beyond DENV.

  7. Aedes aegypti Global Suitability Maps Using a Water Container Energy Balance Model for Dengue Risk Applications

    Science.gov (United States)

    Steinhoff, D.

    2015-12-01

    Dengue infections are estimated to total nearly 400 million per year worldwide, with both the geographic range and the magnitude of infections having increased in the past 50 years. The primary dengue vector mosquito Aedes aegypti is closely associated with humans. It lives exclusively in urban and semi-urban areas, preferentially bites humans, and spends its developmental stages in artificial water containers. Climate regulates the development of Ae. aegypti immature mosquitoes in artificial containers. Potential containers for Ae. aegypti immature development include, but are not limited to, small sundry items (e.g., bottles, cans, plastic containers), buckets, tires, barrels, tanks, and cisterns. Successful development of immature mosquitoes from eggs to larvae, pupae, and eventually adults is largely dependent on the availability of water and the thermal properties of the water in the containers. Recent work has shown that physics-based approaches toward modeling container water properties are promising for resolving the complexities of container water dynamics and the effects on immature mosquito development. An energy balance container model developed by the author, termed the Water Height And Temperature in Container Habitats Energy Model (WHATCH'EM), solves for water temperature and height for user-specified containers with readily available weather data. Here we use WHATCH'EM with NASA Earth Science products used as input to construct global suitability maps based on established water temperature ranges for immature Ae. aegypti mosquitoes. A proxy for dengue risk is provided from habitat suitability, but also population estimates, as Ae. aegypti is closely associated with human activity. NASA gridded Global Population of the World data is used to mask out rural areas with low dengue risk. Suitability maps are illustrated for a variety of containers (size, material, color) and shading scenarios.

  8. Oral susceptibility of Singapore Aedes (Stegomyia aegypti (Linnaeus to Zika virus.

    Directory of Open Access Journals (Sweden)

    MeiZhi Irene Li

    Full Text Available Zika virus (ZIKV is a little known flavivirus that caused a major outbreak in 2007, in the South-western Pacific Island of Yap. It causes dengue-like syndromes but with milder symptoms. In Africa, where it was first isolated, ZIKV is mainly transmitted by sylvatic Aedes mosquitoes. The virus has also been isolated from Ae. aegypti and it is considered to be the vector involved in the urban transmission of the virus. Transmission of the virus by an African strain of Ae. aegypti has also been demonstrated under laboratory conditions. The aim of the present study is to describe the oral susceptibility of a Singapore strain of Ae. aegypti to ZIKV, under conditions that simulate local climate.To assess the receptivity of Singapore's Ae. aegypti to the virus, we orally exposed a local mosquito strain to a Ugandan strain of ZIKV. Upon exposure, fully engorged mosquitoes were maintained in an environmental chamber set at 29 °C and 70-75% RH. Eight mosquitoes were then sampled daily from day 1 to day 7, and subsequently on days 10 and 14 post exposure (pe. The virus titer of the midgut and salivary glands of each mosquito were determined using a tissue culture infectious dose(50 (TCID(50 assay. High midgut infection and salivary gland dissemination rates were observed. By day 5 after the infectious blood meal, ZIKV was found in the salivary glands of more than half of the mosquitoes tested (62%; and by day 10, all mosquitoes were potentially infective.This study showed that Singapore's urban Ae. aegypti are susceptible and are potentially capable of transmitting ZIKV. The virus could be established in Singapore should it be introduced. Nevertheless, Singapore's current dengue control strategy is applicable to control ZIKV.

  9. Excito-repellency of essential oils against an Aedes aegypti (L.) field population in Thailand.

    Science.gov (United States)

    Boonyuan, Wasana; Grieco, John P; Bangs, Michael J; Prabaripai, Atchariya; Tantakom, Siripun; Chareonviriyaphap, Theeraphap

    2014-06-01

    An investigation of the behavioral responses of Aedes aegypti (= Stegomyia aegypti) to various concentrations of essential oils (2.5, 5, and 10%) extracted from hairy basil (Ocimum americanum Linn), ginger (Zingiber officinale Roscoe), lemongrass (Cymbopogon citratus Stapf), citronella grass (Cymbopogon nardus Rendle), and plai (Zingiber cassumunar Roxb) were performed using an excito-repellency test chamber. Results showed that Ae. aegypti exhibited varying levels of escape response in both the contact and noncontact chambers in response to different essential oils. The magnitude of the behaviors changed in a dose-response fashion depending on the percent volume to volume concentration of oil used. A 2.5% concentration of hairy basil oil produced a significantly greater escape response compared to the other extracts at the same concentration (P< 0.05). Oils of ginger, lemongrass, and citronella produced stronger irritant and repellent responses at the median 5% concentration compared to the lowest and highest concentrations. There was marked suppression of escape for both contact and noncontact tests using 10% concentrations of hairy basil, lemongrass, and citronella, with high knockdown for all three oils after 30 min. Hairy basil and lemongrass had the highest insecticidal activity to Ae. aegypti, with LC50 values of 6.3 and 6.7 percent, respectively. We conclude that the essential oils from native plants tested, and likely many other extracts found in plants, have inherent repellent and irritant qualities that should to be screened and optimized for their behavior-modifying properties against Ae. aegypti and other biting arthropods of public health and pest importance. PMID:24820563

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

    Science.gov (United States)

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

    2015-12-01

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

  11. Spatial patterns of high Aedes aegypti oviposition activity in northwestern Argentina.

    Directory of Open Access Journals (Sweden)

    Elizabet Lilia Estallo

    Full Text Available BACKGROUND: In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. METHODOLOGY: Oviposition activity was detected in Orán City (Salta province using ovitraps, weekly replaced (October 2005-2007. Spatial autocorrelation was measured with Moran's Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. PRINCIPAL FINDINGS: Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC=0.77, obtaining 99% of sensitivity and 75.29% of specificity. CONCLUSIONS: Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist

  12. The wMel Strain of Wolbachia Reduces Transmission of Chikungunya Virus in Aedes aegypti

    Science.gov (United States)

    Aliota, Matthew T.; Walker, Emma C.; Uribe Yepes, Alexander; Dario Velez, Ivan; Christensen, Bruce M.; Osorio, Jorge E.

    2016-01-01

    Background New approaches to preventing chikungunya virus (CHIKV) are needed because current methods are limited to controlling mosquito populations, and they have not prevented the invasion of this virus into new locales, nor have they been sufficient to control the virus upon arrival. A promising candidate for arbovirus control and prevention relies on the introduction of the intracellular bacterium Wolbachia into Aedes aegypti mosquitoes. This primarily has been proposed as a tool to control dengue virus (DENV) transmission; however, evidence suggests Wolbachia infections confer protection for Ae. aegypti against CHIKV. Although this approach holds much promise for limiting virus transmission, at present our understanding of the ability of CHIKV to infect, disseminate, and be transmitted by wMel-infected Ae. aegypti currently being used at Wolbachia release sites is limited. Methodology/Principal Findings Using Ae. aegypti infected with the wMel strain of Wolbachia that are being released in Medellin, Colombia, we report that these mosquitoes have reduced vector competence for CHIKV, even with extremely high viral titers in the bloodmeal. In addition, we examined the dynamics of CHIKV infection over the course of four to seven days post feeding. Wolbachia-infected mosquitoes remained non-infective over the duration of seven days, i.e., no infectious virus was detected in the saliva when exposed to bloodmeals of moderate viremia, but CHIKV-exposed, wild type mosquitoes did have viral loads in the saliva consistent with what has been reported elsewhere. Finally, the presence of wMel infection had no impact on the lifespan of mosquitoes as compared to wild type mosquitoes following CHIKV infection. Conclusions/Significance These results could have an impact on vector control strategies in areas where Ae. aegypti are transmitting both DENV and CHIKV; i.e., they argue for further exploration, both in the laboratory and the field, on the feasibility of expanding this

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

    Directory of Open Access Journals (Sweden)

    Thirumalapura Krishnaiah Mohankumar

    2016-01-01

    Full Text Available Background: Mosquitoes transmit serious human diseases, causing millions of death every year. Vector control is facing a threat due to the emergence of resistance to synthetic insecticides. Insecticides of botanical origin may serve as suitable alternative biocontrol techniques in the future. Nine different locally available medicinally important plants suspected to posse larvicidal property were screened against fourth instar larvae of Aedes aegypti and Anoph­eles stephensi to a series of concentrations of the methanolic extracts.Methods: Susceptibility tests on Ae. aegypti and An. stephensi were conducted using standard WHO methods. The larvae of two mosquito species were exposed to methanolic extracts and mortality counts were made after 24 hours of exposure as per WHO method. Larvae of Ae. aegypti were more susceptible than that of An. stephensi.Results: Among the nine plant species tested, Annona reticulata leaf extract was more effective against Ae. aegypti larvae with LC50 and LC90 values of 95.24 and 262.64 ppm respectively and against An. stephensi larvae 262.71 and 636.94 ppm respectively. The least efficacy was in Cosmos bipinnatus with LC50 and LC90 values of 442.6 and 1225.93 ppm against Ae. aegypti and LC50 and LC90 values of 840.69 and 1334.01 ppm of Thespesia populnea against An. stephensi.Conclusion: The crude methanolic extract of the An. reticulata with good larvicidal efficacy could be considered for further characterization to control mosquito vectors instead of chemical insecticides. High efficacy found in An. re­ticulata extract will be considered for further studies to isolate the bioactive compound.

  14. Genetic Diversity and Phylogeny of Aedes aegypti, the Main Arbovirus Vector in the Pacific.

    Directory of Open Access Journals (Sweden)

    Elodie Calvez

    2016-01-01

    Full Text Available The Pacific region is an area unique in the world, composed of thousands of islands with differing climates and environments. The spreading and establishment of the mosquito Aedes aegypti in these islands might be linked to human migration. Ae. aegypti is the major vector of arboviruses (dengue, chikungunya and Zika viruses in the region. The intense circulation of these viruses in the Pacific during the last decade led to an increase of vector control measures by local health authorities. The aim of this study is to analyze the genetic relationships among Ae. aegypti populations in this region.We studied the genetic variability and population genetics of 270 Ae. aegypti, sampled from 9 locations in New Caledonia, Fiji, Tonga and French Polynesia by analyzing nine microsatellites and two mitochondrial DNA regions (CO1 and ND4. Microsatellite markers revealed heterogeneity in the genetic structure between the western, central and eastern Pacific island countries. The microsatellite markers indicate a statistically moderate differentiation (FST = 0.136; P < = 0.001 in relation to island isolation. A high degree of mixed ancestry can be observed in the most important towns (e.g. Noumea, Suva and Papeete compared with the most isolated islands (e.g. Ouvea and Vaitahu. Phylogenetic analysis indicated that most of samples are related to Asian and American specimens.Our results suggest a link between human migrations in the Pacific region and the origin of Ae. aegypti populations. The genetic pattern observed might be linked to the island isolation and to the different environmental conditions or ecosystems.

  15. Aedes aegypti uses RNA interference in defense against Sindbis virus infection

    Directory of Open Access Journals (Sweden)

    Wilusz Jeffrey

    2008-03-01

    Full Text Available Abstract Background RNA interference (RNAi is an important anti-viral defense mechanism. The Aedes aegypti genome encodes RNAi component orthologs, however, most populations of this mosquito are readily infected by, and subsequently transmit flaviviruses and alphaviruses. The goal of this study was to use Ae. aegypti as a model system to determine how the mosquito's anti-viral RNAi pathway interacts with recombinant Sindbis virus (SINV; family Togaviridae, genus Alphavirus. Results SINV (TR339-eGFP (+ strand RNA, infectious virus titers and infection rates transiently increased in mosquitoes following dsRNA injection to cognate Ago2, Dcr2, or TSN mRNAs. Detection of SINV RNA-derived small RNAs at 2 and 7 days post-infection in non-silenced mosquitoes provided important confirmation of RNAi pathway activity. Two different recombinant SINV viruses (MRE16-eGFP and TR339-eGFP with significant differences in infection kinetics were used to delineate vector/virus interactions in the midgut. We show virus-dependent effects on RNAi component transcript and protein levels during infection. Monitoring midgut Ago2, Dcr2, and TSN transcript levels during infection revealed that only TSN transcripts were significantly increased in midguts over blood-fed controls. Ago2 protein levels were depleted immediately following a non-infectious bloodmeal and varied during SINV infection in a virus-dependent manner. Conclusion We show that silencing RNAi components in Ae. aegypti results in transient increases in SINV replication. Furthermore, Ae. aegypti RNAi is active during SINV infection as indicated by production of virus-specific siRNAs. Lastly, the RNAi response varies in a virus-dependent manner. These data define important features of RNAi anti-viral defense in Ae. aegypti.

  16. Sitios de Cría del Aedes aegypti en la Provincia de Limón, Costa Rica Breeding sites of Aedes aegypti in the province of Limón, Costa Rica

    Directory of Open Access Journals (Sweden)

    Rodrigo Marín Rodríguez

    2012-06-01

    Full Text Available En Costa Rica el dengue constituye la principal enfermedad de transmisión vectorial. Su control requiere un conocimiento integral de su vector Aedes aegypti, el cual utiliza gran variedad de recipientes artificiales para su cría. Objetivos: Identificar y describir los principales sitios de cría del A. aegypti en la provincia de Limón. Materiales y Métodos: El muestreo se realizó por el personal del programa de control de vectores durante el año 2011; de forma simultánea en los seis cantones que conforman la provincia de Limón. Resultados: Se identifico la presencia de A. aegypti en los seis cantones de la provincia de Limón. Los sitios de cría mas frecuentes fueron las llantas, los tarros o depósitos inservibles, los baldes y los tanques. Conclusiones: La proliferación del A. aegypti está directamente relacionado con el hombre, sus malos hábitos, y por la calidad de los servicios de salud de protección y mejoramiento del ambiente humano. Estos resultados demuestran que el abordaje del control del A. aegypti debe ser integral.Dengue is the main disease due to vectorial transmission in Costa Rica. Its control requires comprehensive knowledge of its vector which uses a wide variety of artificial containers for breeding. Objectives: To identify and describe Aedes aegypti breeding sites present in the Limon province of Costa Rica. Materials and methods: this survey was carried out during the year 2011 by personnel of the Vector Control Program working simultaneously in six municipalities of the studied region. Results: We identified the presence of Aedes aegypti in six municipalities in the province of Limon. The most frequent breeding sites were tires, cans or unusable deposits, buckets and tanks. Conclusions: Proliferation of Aedes aegypti is directly related to man, his bad habits, and to the quality of health care models regarding protection and improvement of the human environment. These results show that the approach to

  17. Spatial and temporal patterns in pupal and adult production of the dengue vector Aedes aegypti in Kamphaeng Phet, Thailand

    NARCIS (Netherlands)

    Koenraadt, C.J.M.; Aldstadt, J.; Kijchalao, U.; Sithiprasasna, R.; Getis, A.; Jones, J.W.; Scott, T.W.

    2008-01-01

    We investigated how temporal and spatial effects confound the functional relationship between pupal and adult populations of Aedes aegypti and thus the value of pupal numbers as predictors of dengue transmission risk in Kamphaeng Phet, Thailand. We found considerable seasonal shifts in productivity

  18. 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...

  19. 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

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

    Science.gov (United States)

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