Mathematical model of temephos resistance in Aedes aegypti mosquito population

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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.

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

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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. © 2016 The Royal Entomological Society.

Swarming Mechanisms in the Yellow Fever Mosquito: Aggregation Pheromones are Involved in the Mating Behavior of Aedes aegypti

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2014-12-01

behavior of Aedes aegypti Emadeldin Y. Fawaz1, Sandra A. Allan2, Ulrich R. Bernier2, Peter J. Obenauer3, and Joseph W. Diclaro II1 1Vector Biology... Aedes aegypti swarming behavior and identified associated chemical cues. Novel evidence is provided that Ae. aegypti females aggregate by means of...the isolated aggregation pheromones in controlling Ae. aegypti. Journal of Vector Ecology 39 (2): 347-354. 2014. Keyword Index: Aedes aegypti, swarm

Insecticide susceptibility of Aedes aegypti and Aedes albopictus in Central Africa

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Nwane Philippe

2011-05-01

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

Laboratory Evaluation of a Novel Lethal Ovitrap for Control of Aedes aegypti

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Aedes aegypti and Aedes albopictus are known to flourish in a variety of natural and residential habitats and are competent vectors of at least 22 different arboviruses including dengue, chikungunya, and zika. Their global distribution, anthropophilic nature, and vector competency make them species ...

The Maxillary Palp of Aedes aegypti, a Model of Multisensory Integration

Science.gov (United States)

2014-01-01

The maxillary palp of Aedes aegypti, a model of multisensory integration Jonathan D. Bohbot, Jackson T. Sparks, Joseph C. Dickens* United States...24 February 2014 Keywords: Aedes aegypti Olfaction Mosquito Maxillary palp Thermosensation Mechanosensation a b s t r a c t Female yellow-fever...mosquitoes, Aedes aegypti, are obligate blood-feeders and vectors of the pathogens that cause dengue fever, yellow fever and Chikungunya. This feeding

Comparison of BG-Sentinel® Trap and Oviposition Cups for Aedes aegypti and Aedes albopictus Surveillance in Jacksonville, Florida, USA.

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Wright, Jennifer A; Larson, Ryan T; Richardson, Alec G; Cote, Noel M; Stoops, Craig A; Clark, Marah; Obenauer, Peter J

2015-03-01

The BG-Sentinel® (BGS) trap and oviposition cups (OCs) have both proven effective in the surveillance of Aedes species. This study aimed to determine which of the 2 traps could best characterize the relative population sizes of Aedes albopictus and Aedes aegypti in an urban section of Jacksonville, FL. Until 1986, Ae. aegypti was considered the dominant container-breeding species in urban northeastern Florida. Since the introduction of Ae. albopictus, Ae. aegypti has become almost completely extirpated. In 2011, a resurgence of Ae. aegypti was detected in the urban areas of Jacksonville; thus this study initially set out to determine the extent of Ae. aegypti reintroduction to the area. We determined that the BGS captured a greater number of adult Ae. aegypti than Ae. albopictus, while OCs did not monitor significantly different numbers of either species, even in areas where the BGS traps suggested a predominance of one species over the other. Both traps were effective at detecting Aedes spp.; however, the BGS proved more diverse by detecting over 20 other species as well. Our results show that in order to accurately determine vectorborne disease threats and the impact of control operations on these 2 species, multiple trapping techniques should be utilized when studying Ae. aegypti and Ae. albopictus population dynamics.

Evaluación del temefos y pyriproxifeno para el control de larvas de Aedes aegypti en condiciones de laboratorio

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Pérez, María; Ministerio de Salud. Lima, Perú.

2017-01-01

Objetivo: Evaluar la eficacia del temefos frente al pyriproxifeno a diferentes dosis (0.01, 0.02, 0.03, 0.04 y 0.05 ppb) para el control de larvas de Aedes aegypti en condiciones de laboratorio.Materiales y métodos: Estudio experimental con grupo de control, que incorporó a 2000 larvas de Aedes aegypti provenientes de la jurisdicción de Collique III Zona, Comas - Perú, y la cepa Rockefeller como control susceptible. Sedeterminó la diferencia en tiempo de inicio de la acción larvicida; así mis...

UDP-N-Acetyl glucosamine pyrophosphorylase as novel target for controlling Aedes aegypti – molecular modeling, docking and simulation studies

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Bhagath Kumar Palaka

2014-12-01

Full Text Available Aedes aegypti is a vector that transmits diseases like dengue fever, chikungunya, and yellow fever. It is distributed in all tropical and subtropical regions of the world. According to WHO reports, 40% of the world’s population is currently at risk for dengue fever. As vaccines are not available for such diseases, controlling mosquito population becomes necessary. Hence, this study aims at UDP-N-acetyl glucosamine pyrophosphorylase of Aedes aegypti (AaUAP, an essential enzyme for chitin metabolim in insects, as a drug target. Structure of AaUAP was predicted and validated using in-silico approach. Further, docking studies were performed using a set of 10 inhibitors out of which NAG9 was found to have good docking score, which was further supported by simulation studies. Hence, we propose that NAG9 can be considered as a potential hit in designing new inhibitors to control Aedes aegypti.

Survey on aedes mosquito density and pattern distribution of aedes aegypti and aedes albopictus in high and low incidence districts in north sumatera province

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Siregar, Fazidah A.; Makmur, Tri

2018-03-01

Transmission and control of dengue hemorrhagic fever are related to its vectors. This study investigated vector density and distribution patterns of Aedes aegypty and Aedes albopictus in Medan and Langkat as high and low incidence district, respectively. An entomological survey was carried out in 304 households both in Medan and Langkat. The results showed that adult Ae. aegypti were predominantly in Medan, while adult Ae. albopictus was only in Langkat. Larvae indices (HI, CI, BI) for Aedes in Medan ( 35,13 and 43) were higher than langkat ( 22,8 and 30). Adult indices (AHI, AD, RR) for Ae. aegypti in Medan and for Ae. albopictus in Langkat were 20,38,24 and 3,5, and 5, respectively. Pattern distribution of Aedes larvae and adult mosquitoes in both district had similar pattern. Aedes larval indices and adult indices both in HIDs and LIDs were above the critical level, indicating potential high risk for DHF transmission. By multiple regression analysis, HI is predictor for DHF transmission in North Sumatera. Thus, in designing an effective control measures for dengue hemorrhagic fever, monitoring distribution and vector density is crucial.

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

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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.

[Potential of Bacillus thuringiensis israelensis Berliner for controlling Aedes aegypti].

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Polanczyk, Ricardo Antonio; Garcia, Marcelo de Oliveira; Alves, Sérgio Batista

2003-12-01

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.

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

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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...

Detecção de Aedes aegypti e Aedes albopictus, na zona urbana do município de Catanduva-SP, após controle de epidemia de dengue

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Rubens Pinto Cardoso Junior

1997-02-01

Full Text Available Após a realização dos trabalhos de controle visando à interrupção da transmissão do vírus do dengue, iniciou-se um trabalho de monitorização de Aedes aegypti e Aedes albopictus com dois métodos de vigilância entomológica: Índice de Breteau (IB e ovitrampas. Pretendeu-se avaliar o tempo necessário para que as espécies envolvidas fossem novamente detectadas na área urbana do município de Catanduva, SP. As ovitrampas apresentaram positividade para Aedes aegypti dois meses após os trabalhos de controle, enquanto o Índice de Breteau veio a positivar-se somente no quarto mês após o término dos referidos trabalhos.After the realization of control research that had in view the transmition of dengue virus, we started to monitor two kinds of entomological vigilance, Breteau Index and ovitrap. We intended to evaluate the necessary time elapsed before Aedes sp mosquitoes were again detected at the urban area of Catanduva s town (SP. The ovitraps showed positiviness for the Aedes aegypti two months after the control research, while the Breteau Index became positive only at the fourth month after the end of the refered research.

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

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Jonny E Duque Luna

2004-12-01

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

Role of Aedes aegypti (Linnaeus) and Aedes albopictus (Skuse) in local dengue epidemics in Taiwan.

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Tsai, Pui-Jen; Teng, Hwa-Jen

2016-11-09

Aedes mosquitoes in Taiwan mainly comprise Aedes albopictus and Ae. aegypti. However, the species contributing to autochthonous dengue spread and the extent at which it occurs remain unclear. Thus, in this study, we spatially analyzed real data to determine spatial features related to local dengue incidence and mosquito density, particularly that of Ae. albopictus and Ae. aegypti. We used bivariate Moran's I statistic and geographically weighted regression (GWR) spatial methods to analyze the globally spatial dependence and locally regressed relationship between (1) imported dengue incidences and Breteau indices (BIs) of Ae. albopictus, (2) imported dengue incidences and BI of Ae. aegypti, (3) autochthonous dengue incidences and BI of Ae. albopictus, (4) autochthonous dengue incidences and BI of Ae. aegypti, (5) all dengue incidences and BI of Ae. albopictus, (6) all dengue incidences and BI of Ae. aegypti, (7) BI of Ae. albopictus and human population density, and (8) BI of Ae. aegypti and human population density in 348 townships in Taiwan. In the GWR models, regression coefficients of spatially regressed relationships between the incidence of autochthonous dengue and vector density of Ae. aegypti were significant and positive in most townships in Taiwan. However, Ae. albopictus had significant but negative regression coefficients in clusters of dengue epidemics. In the global bivariate Moran's index, spatial dependence between the incidence of autochthonous dengue and vector density of Ae. aegypti was significant and exhibited positive correlation in Taiwan (bivariate Moran's index = 0.51). However, Ae. albopictus exhibited positively significant but low correlation (bivariate Moran's index = 0.06). Similar results were observed in the two spatial methods between all dengue incidences and Aedes mosquitoes (Ae. aegypti and Ae. albopictus). The regression coefficients of spatially regressed relationships between imported dengue cases and Aedes mosquitoes

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

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Marina Stein

2002-10-01

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

Tingkat Kerentanan Aedes aegypti (Linn. terhadap Malation di Provinsi Sumatera Selatan

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Lasbudi P. Ambarita

2015-07-01

Full Text Available AbstractDengue vector control program in Indonesia and also South Sumatera Province has been using malathion quite long enough. The extensive use of chemical in dengue vector control can lead to development of resistance. This study aims to determine the susceptibility of Aedes aegypti against malathion in 11 district of South Sumatera Province. Larva or pupae were collected with entomology survey kit and colonized until first generation (F1 that were used for bioassay. This test was conducted according to WHO adult susceptibility bioassay procedure.Twenty five blood-fed mosquitoes were exposed to insecticide impregnated paper in each of 4 WHO test kits and 1 control tube. Aedes aegypti from all study sites were still susceptible to operational dose of malathion (5%after 1 hour exposure. The estimated resistance ratio (ERR of knockdown time (KT to operasional dose of malathion is about 1,02 – 1,27 for KT50 and 0,96 – 1,24 for KT95. The susceptibility test of adult mosquitoes to diagnostic dose (0,8% of malathion showed a variety of susceptibility after 24 hours. Strain of 7 districts showed resistance, 3 districts toleran and 1 district still susceptible. The detection of resistance can actually help public health personnel to formulate appropriate steps in encountering the reduction in effectiveness of vector control efforts.Keywords : Aedes aegypti, Malathion, Susceptibility, South SumateraAbstrakProgram pengendalian vektor DBD di Indonesia termasuk di Provinsi Sumatera Selatan telah cukup lama menggunakan malation dengan konsentrasi 5%. Penggunaan satu jenis insektisida kimiawi secara ekstensif dapat memicu perkembangan resistensi. Penelitian ini bertujuan untuk menentukan status kerentanan Aedes aegypti terhadap malation dari 11 kabupaten/kota di Provinsi Sumatera Selatan. Larva atau pupa dikumpulkan menggunakan alat survei entomologi dan selanjutnyadipelihara hingga mendapatkan generasi pertama (F1 yang akan digunakan pada uji

Comparison of BG-Sentinel Trap and Oviposition Cups for Aedes aegypti and Aedes albopictus Surveillance in Jacksonville, Florida, USA

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2015-03-01

COMPARISON OF BG-SENTINELH TRAP AND OVIPOSITION CUPS FOR AEDES AEGYPTI AND AEDES ALBOPICTUS SURVEILLANCE IN JACKSONVILLE, FLORIDA, USA JENNIFER A...trap and oviposition cups (OCs) have both proven effective in the surveillance of Aedes species. This study aimed to determine which of the 2 traps could...best characterize the relative population sizes of Aedes albopictus and Aedes aegypti in an urban section of Jacksonville, FL. Until 1986, Ae

Comportamento de formas imaturas de Aedes aegypti, no litoral do Estado de São Paulo Behavior of immatures Aedes aegypti in the coast State of São Paulo, Brazil

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Carmen Moreno Glasser

2011-06-01

Full Text Available INTRODUÇÃO: Em região de alta incidência de dengue, no litoral do Estado de São Paulo, selecionaram-se 9 áreas, com objetivo de avaliar o comportamento de formas imaturas de Aedes aegypti. MÉTODOS: As 9 áreas foram agrupadas em 4 estratos, diferenciados pelo uso e ocupação do solo. Foram coletadas larvas e pupas numa amostra de cerca de 500 imóveis em cada área. RESULTADOS: Apesar do pneu e lona apresentarem as maiores taxas de positividade para Aedes aegypti, o ralo, juntamente com outros recipientes fixos nas edificações foram altamente predominantes entre os recipientes positivos (32 a 76% dos recipientes positivos. As áreas coletivas de prédios e os imóveis não residenciais de grande porte apresentaram as maiores taxas de positividade para Aedes aegypti enquanto os apartamentos, as menores. Os níveis de infestação foram maiores na área residencial com predominância de prédios de apartamentos, onde 76% dos criadouros detectados foram recipientes fixos nas edificações. CONCLUSÕES: Esses conhecimentos são importantes subsídios para a estratégia de controle, pois reforçam a necessidade de atenção especial para determinados tipos de imóveis, bem como da adequação da norma técnica de ralo de água pluvial e da melhoria de manutenção das edificações. Além disso, são necessárias observações sistemáticas que permitam acompanhar a dinâmica de ocupação de diferentes imóveis e recipientes por Aedes aegypti e a incorporação desses conhecimentos nas ações de controle do vetor na região.INTRODUCTION: In a region of high dengue incidence, on the coast of the State of São Paulo, 9 areas were selected to evaluate the behavior of immature Aedes aegypti. METHODS: The 9 areas were grouped into 4 strata according to soil use and occupation. Larvae and pupas were collected in a sample of approximately 500 buildings in each area. RESULTS: Although tires and canvas presented the highest positive rates for

Optimization of the Aedes aegypti Control Strategies for Integrated Vector Management

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Marat Rafikov

2015-01-01

Full Text Available We formulate an infinite-time quadratic functional minimization problem of Aedes aegypti mosquito population. Three techniques of mosquito population management, chemical insecticide control, sterile insect technique control, and environmental carrying capacity reduction, are combined in order to obtain the most sustainable strategy to reduce mosquito population and consequently dengue disease. The solution of the optimization control problem is based on the ideas of the Dynamic Programming and Lyapunov Stability using State-Dependent Riccati Equation (SDRE control method. Different scenarios are analyzed combining three mentioned population management efforts in order to assess the most sustainable policy to reduce the mosquito population.

Potensi Serbuk Daun Sirih (piper betle, Linn Sebagai Larvasida Nyamuk Aedes aegypti

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Betriyon Betriyon

2017-02-01

Full Text Available Abstract Larvacide was compound/essence used to kill  larvae stadium. Many people used Piper betle to traditional medicine. Piper betle plant L,.has contents bioactive compound as flavonoid compound, atsiri volatile, polifenol, tannin, alkaloid and saponin which have quality as larvacide. Based on the case above, this research aim to put the experiment Piper betle of the Aedes aegypti mosquito instars IV. This was pure experiment research using complete random design. This research was done at laboratory . Larva used was  Aedes aegypti mosquito instars IV. Concentration used of this research was : 0,1; 0,2; 0,3; 0,4; 05 percent b/v. This research has control (+ was temephos 0,0001 persen, control (- was aquades water not added anything. Observation done every hour up to all the larva death with the replication 5 times. Larva death cumulative data on 10th hour and 24 th used to calculate LC50 and LT50 used probit regression analysis than data analyzed using Levene’s test. The result of this research showed that the cost of LC50 piper betle plant L. on 10th hour was 0,54 ± 0,147 persen b/v, than on 24 hour LC50 on concentration 0,07 up to 0,28 percent b/v. the time needed to cross out 50 percent Aedes aegypti instar IV of the concentration 0,05 percent time needed 19. Based on a probit analysis of the relationship between the level of concentration with the number of larvae mortality, Piper betle have activities as larvacide of Aedes aegypti. Keywods: piper betle leaf powder, larvacide, Aedes aegyti AbstrakLarvasida adalah senyawa/zat yang digunakan untuk membunuh stadium larva. Tanaman Piper betle, Linn. (sirih hijau sudah banyak dimanfaatkan oleh kalangan masyarakat sebagai obat tradisional. Daun sirih hijau memiliki kandungan senyawa bioaktif seperti senyawa flavonoid, minyak atsiri, polifenol, tannin, alkaloid dan saponin yang dapat bersifat sebagai larvasida. Penelitian ini bertujuan untuk mengetahui manfaat daun sirih hijau yaitu

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

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S Sulaiman

2008-12-01

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

Toxicity of Thiophenes from Echinops transiliensis (Asteraceae) against Aedes aegypti (Diptera: Culicidae) Larvae

Science.gov (United States)

2014-01-01

Toxicity of Thiophenes from Echinops transiliensis (Asteraceae) against Aedes aegypti (Diptera: Culicidae) Larvae by Hiroshi Nakano*a)b)c), Abbas...larvicides against Aedes aegypti. Structural differences among compounds 3, 5, and 8 consisted in differing AcO and OH groups attached to C(3’’) and C(4...serious human diseases including malaria, Japanese encephalitis, yellow fever, dengue, and filariasis. The urban-adapted Aedes aegypti mosquito has become

PENGAMATAN TEMPAT PERINDUKAN AEDES AEGYPTI PADA TEMPAT PENAMPUNGAN AIR RUMAH TANGGA PADA MASYARAKAT PENGGUNA AIR OLAHAN

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H. Hasyimi

2012-11-01

Full Text Available An observation of Aedes aegypti breeding places in domestic pipe waters container provided by PAM (Water supply company customer regency was carried out. The area observation in RW (a hamlet 05 kelurahan Papanggo Tanjung priuk North Jakarta. As a control area, RW 04 kelurahan Tanjung Priok in the same district was selected. The observation was conducted on Agust - September 2001. The result showed that Aedes aegypti larvae were found mostly in clay water container or tempayan (66,7 %. The house index (HI rate is 27,3%. In the control area the larvae were found predominantly in bath cistern (65,4% and HI rate is 100%. So in the study area HI rate is lower than in the control area.   Keywords: Aedes aegypti, breeding places, domestic container, house index

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

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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

[Behavior of immatures Aedes aegypti in the coast State of São Paulo, Brazil].

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Glasser, Carmen Moreno; Arduino, Marylene de Brito; Barbosa, Gerson Laurindo; Ciaravolo, Ricardo Mario de Carvalho; Domingos, Maria de Fátima; Oliveira, Cleide Dantas; Pereira, Marisa; Silva, Marcos; Trevisan, Alexandra Myuki Yoshioka

2011-01-01

In a region of high dengue incidence, on the coast of the State of São Paulo, 9 areas were selected to evaluate the behavior of immature Aedes aegypti. The 9 areas were grouped into 4 strata according to soil use and occupation. Larvae and pupas were collected in a sample of approximately 500 buildings in each area. Although tires and canvas presented the highest positive rates for Aedes aegypti, drains and other containers fixed to the buildings were highly predominant among positive containers; 32 to 76% of the positive containers in the 4 study strata. Public areas of apartment buildings and large non-residential premises presented the highest positive rates for Aedes Aegypti, while apartments presented the lowest. Infestation levels were greater in residential areas with predominance of apartment buildings, where 76% of the breeding sites detected were containers fixed to the buildings. This knowledge is an important tool in the control strategy, since it reinforces the need for special attention regarding certain types of buildings and the adjustment of technical norms for pluvial water drains and improvement of building maintenance. Moreover, systematic observations are required to follow-up the occupancy dynamic of different buildings and containers by Aedes aegypti and the incorporation of this knowledge in the control of vectors in the region.

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

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

2012-10-22

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. 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. 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. Aedes aegypti, Insecticides, Susceptibility, Cape Verde, Senegal.

Leaking Containers: Success and Failure in Controlling the Mosquito Aedes aegypti in Brazil.

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Löwy, Ilana

2017-04-01

In 1958, the Pan American Health Organization declared that Brazil had successfully eradicated the mosquito Aedes aegypti, responsible for the transmission of yellow fever, dengue fever, chikungunya, and Zika virus. Yet in 2016 the Brazilian minister of health described the situation of dengue fever as "catastrophic." Discussing the recent epidemic of Zika virus, which amplified the crisis produced by the persistence of dengue fever, Brazil's president declared in January 2016 that "we are in the process of losing the war against the mosquito Aedes aegypti." I discuss the reasons for the failure to contain Aedes in Brazil and the consequences of this failure. A longue durée perspective favors a view of the Zika epidemic that does not present it as a health crisis to be contained with a technical solution alone but as a pathology that has the persistence of deeply entrenched structural problems and vulnerabilities.

Oviposition ecology and species composition of Aedes spp. and Aedes aegypti dynamics in variously urbanized settings in arbovirus foci in southeastern Côte d'Ivoire.

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Zahouli, Julien B Z; Utzinger, Jürg; Adja, Maurice A; Müller, Pie; Malone, David; Tano, Yao; Koudou, Benjamin G

2016-09-29

a regression of the Aedes wild species towards a unique presence of Ae. aegypti in urban areas. Aedes wild species serve as bridge vectors of arboviruses in rural areas, while Ae. aegypti amplifies arbovirus transmission in urban areas. Our results have important ramifications for dengue and yellow fever vector control and surveillance strategies in arbovirus foci in southeastern Côte d'Ivoire.

The immune strategies of mosquito Aedes aegypti against microbial infection.

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Wang, Yan-Hong; Chang, Meng-Meng; Wang, Xue-Li; Zheng, Ai-Hua; Zou, Zhen

2018-06-01

Yellow fever mosquito Aedes aegypti transmits many devastating arthropod-borne viruses (arboviruses), such as dengue virus, yellow fever virus, Chikungunya virus, and Zika virus, which cause great concern to human health. Mosquito control is an effective method to block the spread of infectious diseases. Ae. aegypti uses its innate immune system to fight against arboviruses, parasites, and fungi. In this review, we briefly summarize the recent findings in the immune response of Ae. aegypti against arboviral and entomopathogenic infections. This review enriches our understanding of the mosquito immune system and provides evidence to support the development of novel mosquito control strategies. Copyright © 2017 Elsevier Ltd. All rights reserved.

The effect of photoperiod on life history and blood-feeding activity in Aedes albopictus and Aedes aegypti (Diptera: Culicidae).

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Costanzo, K S; Schelble, S; Jerz, K; Keenan, M

2015-06-01

Several studies have examined how climatic variables such as temperature and precipitation may affect life history traits in mosquitoes that are important to disease transmission. Despite its importance as a seasonal cue in nature, studies investigating the influence of photoperiod on such traits are relatively few. This study aims to investigate how photoperiod alters life history traits, survival, and blood-feeding activity in Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus). We performed three experiments that tested the effects of day length on female survival, development time, adult size, fecundity, adult life span, and propensity to blood feed in Ae. albopictus and Ae. aegypti. Each experiment had three photoperiod treatments: 1) short-day (10L:14D), 2) control (12L:12D), and 3) long-day (14L:10D). Aedes albopictus adult females were consistently larger in size when reared in short-day conditions. Aedes aegypti adult females from short-day treatments lived longer and were more likely to take a blood meal compared to other treatments. We discuss how species-specific responses may reflect alternative strategies evolved to increase survival during unfavorable conditions. We review the potential impacts of these responses on seasonal transmission patterns, such as potentially increasing vectorial capacity of Ae. aegypti during periods of shorter day lengths. © 2015 The Society for Vector Ecology.

Historical inability to control Aedes aegypti as a main contributor of fast dispersal of chikungunya outbreaks in Latin America.

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Fernández-Salas, Ildefonso; Danis-Lozano, Rogelio; Casas-Martínez, Mauricio; Ulloa, Armando; Bond, J Guillermo; Marina, Carlos F; Lopez-Ordóñez, Teresa; Elizondo-Quiroga, Armando; Torres-Monzón, Jorge A; Díaz-González, Esteban E

2015-12-01

The arrival of chikungunya fever (CHIKF) in Latin American countries has been expected to trigger epidemics and challenge health systems. Historically considered as dengue-endemic countries, abundant Aedes aegypti populations make this region highly vulnerable to chikungunya virus (CHIKV) circulation. This review describes the current dengue and CHIKF epidemiological situations, as well as the role of uncontrolled Ae. aegypti and Aedes albopictus vectors in spreading the emerging CHIKV. Comments are included relating to the vector competence of both species and failures of surveillance and vector control measures. Dengue endemicity is a reflection of these abundant and persistent Aedes populations that are now spreading CHIKV in the Americas. This article forms part of a symposium in Antiviral Research on "Chikungunya discovers the New World." Copyright © 2015 Elsevier B.V. All rights reserved.

Recomendaciones para la vigilancia de Aedes aegypti

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Roberto Barrera

2016-09-01

Full Text Available La enfermedades causadas por arbovirus transmitidos por Aedes aegypti, como el dengue, el chikungunya y el zika, continúan aumentando en incidencia anual y expansión geográfica. Una limitación clave para el control de A. aegypti ha sido la ausencia de herramientas eficaces para vigilar su población y poder determinar las medidas de control que realmente funcionan. La vigilancia de A. aegypti se ha basado principalmente en la obtención de los índices aédicos, los cuales guardan poca relación con el número de hembras del mosquito, que son las responsables de la transmisión de los virus. El reciente desarrollo de técnicas de muestreo de adultos de este vector promete facilitar las labores de vigilancia y control. En esta revisión se presentan las diversas técnicas de vigilancia del mosquito, así como una discusión sobre su utilidad, con recomendaciones para lograr una vigilancia entomológica más efectiva.

Criadouros de Aedes (Stegomyia aegypti (Linnaeus, 1762 em bromélias nativas na Cidade de Vitória, ES Aedes (Stegomyia aegypti (Linnaeus, 1762 breeding sites in native bromeliads in Vitória City, ES

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José Benedito Malta Varejão

2005-05-01

Full Text Available Alguns insetos transmissores de doenças procriam exclusivamente nas proximidades das residências. O Aedes aegypti, responsável por epidemias de dengue em cidades brasileiras, representa sério risco também para a febre amarela. Com o insucesso da campanha de erradicação do inseto, justifica-se a busca de criadouros fora do alcance das medidas de controle atualmente adotadas. Na Cidade de Vitória, ES, investigou-se a ocorrência de criadouros de Aedes aegypti na água coletada em bromélias nativas, sobre as rochas. Paralelamente, avaliou-se a infestação predial nas áreas urbanas contíguas. Em quatro das cinco áreas investigadas foram encontradas larvas de culicídeos nas bromélias, sendo que em duas foi identificado Aedes aegypti. A presença dos criadouros em bromélias não guardou relação com a infestação predial nas áreas próximas. Torna-se necessário definir se os criadouros em bromélias constituem focos primários do Aedes aegypti, ou se representam uma conseqüência da elevada infestação urbana.Some insects that are vectors of human diseases have accompanied man in his migrations throughout the world and breed exclusively in the proximity of human dwellings. The mosquito Aedes aegypti has been responsible for epidemics of dengue in Brazil and its presence also constitutes a serious risk for future outbreaks of urban yellow fever. The failure of campaigns to eradicate this species justifies the search for alternative breeding sites, which may be beyond the reach of present control measures. In this study the occurrence of Aedes aegypti breeding sites in native bromeliads on rocky slopes was investigated in five areas of Vitória, capital of the Brazilian State of Espírito Santo, ES. Water contained in the bromeliads was collected with the aid of a suction apparatus to search for culicid larvae. The degree of infestation of buildings in adjacent urban areas was evaluated simultaneously. Culicid larvae were found in

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

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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. © The American Society of Tropical Medicine and Hygiene.

Differentiation of Aedes aegypti and Aedes notoscriptus (Diptera: Culicidae) eggs using scanning electron microscopy.

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Faull, Katherine J; Williams, Craig R

2016-05-01

Aedes notoscriptus and Aedes aegypti are both peri-domestic, invasive container-breeding mosquitoes. While the two potential arboviral vectors are bionomically similar, their sympatric distribution in Australia is limited. In this study, analyses of Ae. aegypti and Ae. notoscriptus eggs were enabled using scanning electron microscopy. Significant variations in egg length to width ratio and outer chorionic cell field morphology between Ae. aegypti and Ae. notoscriptus enabled distinction of the two species. Intraspecific variations in cell field morphology also enabled differentiation of the separate populations of both species, highlighting regional and global variation. Our study provides a comprehensive comparative analysis of inter- and intraspecific egg morphological and morphometric variation between two invasive container-breeding mosquitoes. The results indicate a high degree of intraspecific variation in Ae. notoscriptus egg morphology when compared to the eggs of Ae. aegypti. Comparative morphological analyses of Ae. aegypti and Ae. notoscriptus egg attributes using SEM allows differentiation of the species and may be helpful in understanding egg biology in relation to biotope of origin. Copyright © 2016 Elsevier Ltd. All rights reserved.

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

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de Santos, Eloína Maria Mendonça; de Melo-Santos, Maria Alice Varjal; de Oliveira, Claudia Maria Fontes; Correia, Juliana Cavalcanti; de Albuquerque, Cleide Maria Ribeiro

2012-09-07

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. 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. 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. 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 infested by mosquitoes. Low requirements for skilled labor

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

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José Eduardo Bracco

1995-04-01

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

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

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

2015-03-25

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. Aedes mosquitoes were collected from four states in Malaysia in 2010 using ovitraps and tested against six major insecticides using WHO bioassays. Knockdown resistance (kdr) was investigated in both species. A moderate resistance to temephos was detected from samples collected in 2010 in Penang, Kuala Lumpur, Johor Bharu and Kota Bharu (1.5 Malaysia but neither of these mutations were found in Ae. albopictus. Additionally, signatures of selection were detected on the Voltage-gated sodium channel gene in Ae. aegypti but not in Ae. albopictus. The presence of the 1534C allele was significantly associated with pyrethroid resistance and an additive effect to pyrethroid resistance was observed in individuals containing both kdr alleles. Findings from this study will help to design and implement successful insecticide-based interventions against Ae. aegypti and Ae. albopictus to improve dengue control across Malaysia.

Intraspecific Competition and Population Dynamics of Aedes aegypti

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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.

[Susceptibility of Aedes aegypti (L.) strains from Havana to a Bacillus thuringiensis var. israelensis].

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Menéndez Díaz, Zulema; Rodríguez Rodríguez, Jinnay; Gato Armas, René; Companioni Ibañez, Ariamys; Díaz Pérez, Manuel; Bruzón Aguila, Rosa Yirian

2012-01-01

the integration of chemical and biological methods is one of the strategies for the vector control, due to the existing environmental problems and the concerns of the community as a result of the synthetic organic insecticide actions. The bacterium called Bacillus thuringiensis var. israelensis in liquid formulation has been widely used in the vector control programs in several countries and has shown high efficacy at lab in Cuba. to determine the susceptibility of Aedes aegypti collected in the municipalities of La Habana province to Bacillus thuringiensis var. israelensis. fifteen Aedes aegypti strains, one from each municipality, were used including larvae and pupas collected in 2010 and one reference strain known as Rockefeller. The aqueous formulation of Bacillus thuringiensis var. israelensis (Bactivec, Labiofam, Cuba) was used. The bioassays complied with the World Health Organization guidelines for use of bacterial larvicides in the public health sector. The larval mortality was read after 24 hours and the results were processed by the statistical system SPSS (11.0) through Probit analysis. the evaluated mosquito strains showed high susceptibility to biolarvicide, there were no significant differences in LC50 values of Ae. aegypti strains, neither in the comparison of these values with those of the reference strain. the presented results indicate that the use of Bacillus thuringiensis var. israelensis continues to be a choice for the control of Aedes aegypti larval populations in La Habana province.

Mapping the spatial distribution of Aedes aegypti and Aedes albopictus.

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Ding, Fangyu; Fu, Jingying; Jiang, Dong; Hao, Mengmeng; Lin, Gang

2018-02-01

Mosquito-borne infectious diseases, such as Rift Valley fever, Dengue, Chikungunya and Zika, have caused mass human death with the transnational expansion fueled by economic globalization. Simulating the distribution of the disease vectors is of great importance in formulating public health planning and disease control strategies. In the present study, we simulated the global distribution of Aedes aegypti and Aedes albopictus at a 5×5km spatial resolution with high-dimensional multidisciplinary datasets and machine learning methods Three relatively popular and robust machine learning models, including support vector machine (SVM), gradient boosting machine (GBM) and random forest (RF), were used. During the fine-tuning process based on training datasets of A. aegypti and A. albopictus, RF models achieved the highest performance with an area under the curve (AUC) of 0.973 and 0.974, respectively, followed by GBM (AUC of 0.971 and 0.972, respectively) and SVM (AUC of 0.963 and 0.964, respectively) models. The simulation difference between RF and GBM models was not statistically significant (p>0.05) based on the validation datasets, whereas statistically significant differences (p<0.05) were observed for RF and GBM simulations compared with SVM simulations. From the simulated maps derived from RF models, we observed that the distribution of A. albopictus was wider than that of A. aegypti along a latitudinal gradient. The discriminatory power of each factor in simulating the global distribution of the two species was also analyzed. Our results provided fundamental information for further study on disease transmission simulation and risk assessment. Copyright © 2017 Elsevier B.V. All rights reserved.

Effect of temperature on the population dynamics of Aedes aegypti

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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.

Investigating Potential Effects of Dengue Virus Infection and Pre-exposure to DEET on Aedes aegypti Behaviors

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2016-02-05

Investigating Potential Effects of Dengue Virus Infection and Pre-exposure to DEET on Aedes aegypti Behaviors by Victor A...exposure to DEET on Aedes aegypti Behaviors" Name of Candidate: Victor Sugiharto Doctor of Philosophy Degree February 5, 2016 DISSERTATION AND...Infection and Pre-exposure to DEET on Aedes aegypti Behaviors" is appropriately acknowledged and. beyond brief excerpts , is with the permission of

Sodium Channel Mutations and Pyrethroid Resistance in Aedes aegypti

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Yuzhe Du

2016-10-01

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

Identification of germline transcriptional regulatory elements in Aedes aegypti

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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.

Aktivitas Beberapa Atraktan Pada Perangkap Telur Berperekat Terhadap Aedes aegypti

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Milana Salim

2017-02-01

Full Text Available AbstractControl of Aedes aegypti mosquito as dengue haemorrhagic fever/DHF vector can be conducted using the ovitrap modified into a sticky ovitrap. The addition of attractant substances to the ovitrap can attract more mosquitoes comes to the trap, and prevent mosquitoes laying eggs in other places. The aim of this research was to compare hay infusion water and larva rearing water as attractant which combined with sugar-apple (Annona squamosa seed extract by counting the mosquitoes and eggs trapped. This research used six types medium: hay infusion water, larva rearing water, hay infusion water + sugar-apple seed extract, larva rearing water + sugar-apple seed extract, aquadest + sugar-apple seed extract, and aquadest only as a control. Sample used were 25 gravid female of Ae. aegypti mosquitoes with five replications. Mosquitoes and eggs which trapped were counted. This research showed that the number of mosquito trapped and eggs hatched more found in sticky ovitrap with hay infusion water. Statistic analyzed by ANOVA showed that there is no significant difference towards number off mosquito trapped in sticky ovitrap (p>0,05 whereas the medium material has significant difference towards number off egg hatched than others (p<0,05.Keywords: Sticky ovitrap, attractant, Aedes aegypti AbstrakPengendalian nyamuk Aedes aegypti sebagai vektor demam berdarah dengue/DBD dapat dilakukan menggunakan ovitrap yang dimodifikasi dengan perekat menjadi sticky ovitrap. Penambahan atraktan pada ovitrap dapat menarik lebih banyak nyamuk datang ke perangkap yang dipasang dan mencegah nyamuk bertelur di tempat lain. Tujuan penelitian ini adalah untuk mengetahui aktivitas atraktan air rendaman jerami dan air bekas kolonisasi yang dikombinasikan dengan ekstrak biji srikaya pada sticky ovitrap terhadap jumlah nyamuk dan telur yang ditemukan. Enam jenis media uji digunakan dalam penelitian ini yaitu air rendaman jerami, air bekas kolonisasi nyamuk, air rendaman jerami

Co-breeding Association of Aedes albopictus (Skuse) and Aedes aegypti (Linnaeus) (Diptera: Culicidae) in Relation to Location and Container Size.

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Hashim, Nur Aida; Ahmad, Abu Hassan; Talib, Anita; Athaillah, Farida; Krishnan, Kumara Thevan

2018-03-01

The occurrence of major outbreaks of dengue, and other vector borne diseases such as chikungunya and zika in tropical and subtropical regions has rendered control of the diseases a top-priority for many affected countries including Malaysia. Control of the mosquito vectors Aedes aegypti and Aedes albopictus through the reduction of breeding sites and the application of insecticides to kill immature forms and adults are the main control efforts to combat these diseases. The present study describes the association between Ae. albopictus and Ae. aegypti in shared breeding sites. This study is important given that any measure taken against one species may affect the other. A yearlong larval survey was conducted in four dengue endemic areas of Penang Island. Sorenson's coefficient index indicated that no association between number of the immatures of the two species regardless of container size and study location. Therefore, the mean number Ae. albopictus immature was not decreased in the presence of Ae. aegypti in shared breeding container. However Ae. aegypti appeared to prefer breeding in habitats not occupied by Ae. albopictus , the two species sharing breeding sites only where available containers were limited. In control efforts, eliminating the preferred breeding containers for one species might not affect or reduce the population of the other species.

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

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de Santos Eloína Maria

2012-09-01

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

Exploring New Thermal Fog and Ultra-Low Volume Technologies to Improve Indoor Control of the Dengue Vector, Aedes aegypti (Diptera: Culicidae)

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2014-07-01

Dengue Vector, Aedes aegypti (Diptera: Culicidae) JAMES F. HARWOOD,1,2 MUHAMMAD FAROOQ,1 ALEC G. RICHARDSON,1 CARL W. DOUD,1 JOHN L. PUTNAM,3 DANIEL E...vector, Aedes aegypti (L.), inside human habitations must be performed quickly and efÞciently to reduce the risk of transmission during dengue...immediate knockdown of vector populations that may lower the risk of infection and allow other suppression strategies to be implemented. KEY WORDS Aedes

Dengue virus transovarial transmission by Aedes aegypti

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Monica Dwi Hartanti

2016-02-01

Full Text Available Dengue is a disease that is caused by dengue virus and transmitted to humans through the bite of infected Aedes mosquitoes, especially Aedes aegypti. The disease is hyper-endemic in Southeast Asia, where a more severe form, dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS, is a major public health concern. The purpose of the present study was to find evidence of dengue virus transovarial transmision in local vectors in Jakarta. Fifteen Aedes larvae were collected in 2009 from two areas in Tebet subdistrict in South Jakarta, namely one area with the highest and one with the lowest DHF prevalence. All mosquitoes were reared inside two cages in the laboratory, eight mosquitoes in one cage and seven mosquitoes in another cage and given only sucrose solution as their food. The results showed that 20% of the mosquitoes were positive for dengue virus. Dengue virus detection with an immunohistochemical method demonstrated the occurrence of transovarial transmission in local DHF vectors in Tebet subdistrict. Transovarial dengue infection in Ae.aegypti larvae appeared to maintain or enhance epidemics. Further research is needed to investigate the relation of dengue virus transovarial transmission with DHF endemicity in Jakarta.

Dengue virus transovarial transmission by Aedes aegypti

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Monica Dwi Hartanti

2010-08-01

Full Text Available Dengue is a disease that is caused by dengue virus and transmitted to humans through the bite of infected Aedes mosquitoes, especially Aedes aegypti. The disease is hyper-endemic in Southeast Asia, where a more severe form, dengue hemorrhagic fever (DHF and dengue shock syndrome (DSS, is a major public health concern. The purpose of the present study was to find evidence of dengue virus transovarial transmision in local vectors in Jakarta. Fifteen Aedes larvae were collected in 2009 from two areas in Tebet subdistrict in South Jakarta, namely one area with the highest and one with the lowest DHF prevalence. All mosquitoes were reared inside two cages in the laboratory, eight mosquitoes in one cage and seven mosquitoes in another cage and given only sucrose solution as their food. The results showed that 20% of the mosquitoes were positive for dengue virus. Dengue virus detection with an immunohistochemical method demonstrated the occurrence of transovarial transmission in local DHF vectors in Tebet subdistrict. Transovarial dengue infection in Ae.aegypti larvae appeared to maintain or enhance epidemics. Further research is needed to investigate the relation of dengue virus transovarial transmission with DHF endemicity in Jakarta.

The cost of routine Aedes aegypti control and of insecticide-treated curtain implementation.

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Baly, Alberto; Flessa, Steffen; Cote, Marilys; Thiramanus, Thirapong; Vanlerberghe, Veerle; Villegas, Elci; Jirarojwatana, Somchai; Van der Stuyft, Patrick

2011-05-01

Insecticide-treated curtains (ITCs) are promoted for controlling the Dengue vector Aedes aegypti. We assessed the cost of the routine Aedes control program (RACP) and the cost of ITC implementation through the RACP and health committees in Venezuela and through health volunteers in Thailand. The yearly cost of the RACP per household amounted to US$2.14 and $1.89, respectively. The ITC implementation cost over three times more, depending on the channel used. In Venezuela the RACP was the most efficient implementation-channel. It spent US$1.90 (95% confidence interval [CI]: 1.83; 1.97) per curtain distributed, of which 76.9% for the curtain itself. Implementation by health committees cost significantly (P = 0.02) more: US$2.32 (95% CI: 1.93; 2.61) of which 63% for the curtain. For ITC implementation to be at least as cost-effective as the RACP, at equal effectiveness and actual ITC prices, the attained curtain coverage and the adulticiding effect should last for 3 years.

The Effects of Pre-Exposure to DEET on the Downstream Blood-Feeding Behaviors of Aedes aegypti Mosquitoes

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2016-06-10

1 Sugiharto et al.: Aedes aegypti blood- Michael J. Turell 1 feeding after DEET pre-exposure Virology Division, USAMRIID 2 1425 Porter...Pre-exposure to DEET on the Downstream Blood-Feeding Behaviors of 9 Aedes aegypti Mosquitoes1 10 11 Victor A. Sugiharto,2 John P. Grieco,2,3...insect behavior for disease prevention. However, genetic insensitivity and 31 habituation in Aedes aegypti (L.) mosquitoes after pre-exposure to DEET

Synthesis and Mosquitocidal Activity of a Series of Hydrazone Derivatives against Aedes aegypti

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Background: Aedes aegypti is an important mosquito vector for the transmission of several infectious diseases. Current insecticides play a vital role in controlling mosquitoes; however, the frequent use of insecticides has led to the development of insecticide resistance. In order to control mosquit...

Efek Larvasida Bakteri Kitinolitik dari Limbah Kulit Udang terhadap Larva Aedes aegypti

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Dyah Widiastuti

2016-06-01

Full Text Available Abstract. Aedes aegypti is a major vector for Dengue, a deadly disease causing death of millions of people in developing countries both in urban and rural populations. Ae. aegypti control using chemical insecticide was always carried out and lead to a widespread insecticide resistance. Therefore, mosquito biological control is needed to replace the usage of chemical insecticide. A chitinolytic bacteria, was isolated from shrimp’s waste (head and shell. The isolate showed chitinolytic activity as a transparent zone in colony inside the synthetic media, containing (w/v- 0,3 % colloidal chitin, 1% pepton, 0,5% yeast extract, 0,1% NaCl, 0,1% K2HPO4, 0,05% MgSO4.7H2O, 0,001% FeSO4.7H2O, 0,001% ZnSO4.7H2O, and each of 0,0001% CuSO4.5H2O, MnSO4.nH2O and CaCl2.2H2O at pH 7 and 300C after 72 h of incubation. The isolate was identified as gram positive group based on gram staining. In the experimental method, four concentrations of chitinolytic bacteria (4%, 8%, 16% and 32% was exposed to Ae. aegypti larvae. The result showed that chitinolytic bacterium degrades exoskeleton of third instar larvae of Ae. aegypti. Degradation of exoskeleton started on the 2nd days and occurred in thorax region. Probit analysis showed LC50 value was obtaninedat concentration of 2%. Keywords: chitinolytic bacteria, shrimp’s waste, Aedes aegypti Abstrak. Aedes aegypti merupakan vektor utama Dengue, penyakit yang menyebabkan kematian jutaan orang di negara-negara berkembang baik pada populasi perkotaan dan pedesaan. Pengendalian Ae. aegypti menggunakan insektisida kimia selalu dilakukan dan menyebabkan resistensi insektisida secara luas. Oleh karena itu, pengendalian nyamuk secara biologis diperlukan untuk menggantikan penggunaan insektisida kimia. Bakteri kitinolitik telah diisolasi dari limbah udang (kepala dan cangkang. Isolat menunjukkan aktivitas kitinolitik berupa zona bening di sekitar  koloni dalam media sintetik yang mengandung (w/v - 0,3% koloidal kitin, 1

Temporal distribution and insecticide resistance profile of two major arbovirus vectors Aedes aegypti and Aedes albopictus in Yaoundé, the capital city of Cameroon.

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Kamgang, Basile; Yougang, Aurelie P; Tchoupo, Micareme; Riveron, Jacob M; Wondji, Charles

2017-10-10

Aedes aegypti and Ae. albopictus are the major epidemic vectors of several arbovirus diseases such as yellow fever, dengue, Zika and chikungunya worldwide. Both Aedes vectors are presents in Cameroon; however, knowledge on the dynamic of the distribution of these species across cities and their resistance profile to insecticide are limited. Here, we assessed the current distribution of Ae. aegypti and Ae. albopictus in Yaoundé, the Capital City, established the resistance profile to insecticides and explored the resistance mechanisms involved. Immature stages of Aedes were sampled in several breeding sites in December 2015 (dry season) and June 2016 (rainy season) in three central neighborhoods and four peripheral neighborhoods and reared to adult stage. The G0 adults were used for molecular identification and genotyping of F1534C mutation in Ae. aegypti. Bioassays and piperonyl butoxide (PBO) assays were carried out according to WHO guidelines. Analysis revealed that both species Ae. aegypti and Ae. albopictus are present in all prospected sites in Yaounde. However, in the dry season Ae. aegypti is most abundant in neighborhoods located in downtown. In contrast, Ae. albopictus was found most prevalent in suburbs whatever the season and in downtown during the rainy season. Bioassay analysis showed that both Ae. aegypti and Ae. albopictus, are resistant to 0.05% deltamethrin, 0.1% bendiocarb and 4% dichlorodiphenyltrichloroethane (DDT). A decreased of susceptibility to 0.75% permethrin and a full susceptibility to malathion 5% was observed. The mortality rate was increased after pre-exposure to synergist PBO. None of Ae. aegypti assayed revealed the presence of F1534C mutation. These findings are useful to planning vector control programme against arbovirus vectors in Cameroon and can be used as baseline in Africa where data on Aedes resistance is very scarce to plan further works.

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

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

2016-06-08

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. Copyright © 2016 The Author(s). Published by Elsevier Inc. All rights reserved.

Evaluation of Three Commercial Backpack Sprayers with Aqualuer (registered trademark) 20-20 Against Caged Adult Aedes aegypti

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2016-03-11

Sprayers with Aqualuer® 20–20 Against Caged Adult Aedes Aegypti Author(s): Derrick Conover, Ali Fulcher, Michael L. Smith, Muhammad Farooq, Marcia K... AEDES AEGYPTI DERRICK CONOVER,1 ALI FULCHER,1 MICHAEL L. SMITH,1 MUHAMMAD FAROOQ,2 MARCIA K. GAINES1 AND RUI-DE XUE1,3 ABSTRACT. Three commercially...adult Aedes aegypti in semifield trials in northeastern Florida. Two battery-powered sprayers, Birchmeier and Hudson, were compared with the standard

Meta-analysis of studies on chemical, physical and biological agents in the control of Aedes aegypti.

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Lima, Estelita Pereira; Goulart, Marília Oliveira Fonseca; Rolim Neto, Modesto Leite

2015-09-04

Aedes aegypti is a vector of international concern because it can transmit to humans three important arboviral diseases: yellow fever, dengue and chikungunya. Epidemics that are repeated year after year in a variety of urban centers indicate that there are control failures, allowing the vector to continue expanding. To identify the most effective vector control strategies and the factors that contributed to the success or failure of each strategy, we carried out a systematic review with meta-analysis of articles published in 12 databases, from 1974 to the month of December 2013. We evaluated the association between the use of whatever chemical substance, mechanical agent, biological or integrated actions against A. aegypti and the control of the vector, as measured by 10 indicators. We found 2,791 articles, but after careful selection, only 26 studies remained for analysis related to control interventions implemented in 15 countries, with 5 biological, 5 chemical, 3 mechanical and 13 integrated strategies. The comparison among all of them, indicated that the control of A. aegypti is significantly associated with the type of strategy used, and that integrated interventions consist of the most effective method for controlling A. aegypti. The most effective control method was the integrated approach, considering the influence of eco-bio-social determinants in the virus-vector-man epidemiological chain, and community involvement, starting with community empowerment as active agents of vector control.

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

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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.

A cross-sectional survey of Aedes aegypti immature abundance in urban and rural household containers in central Colombia.

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Overgaard, Hans J; Olano, Víctor Alberto; Jaramillo, Juan Felipe; Matiz, María Inés; Sarmiento, Diana; Stenström, Thor Axel; Alexander, Neal

2017-07-27

Aedes aegypti, the major vector of dengue, breeds in domestic water containers. The development of immature mosquitoes in such containers is influenced by various environmental, ecological and socioeconomic factors. Urban and rural disparities in water storage practices and water source supply may affect mosquito immature abundance and, potentially, dengue risk. We evaluated the effect of water and container characteristics on A. aegypti immature abundance in urban and rural areas. Data were collected in the wet season of 2011 in central Colombia from 36 urban and 35 rural containers, which were either mosquito-positive or negative. Immature mosquitoes were identified to species. Data on water and container characteristics were collected from all containers. A total of 1452 Aedes pupae and larvae were collected of which 81% were A. aegypti and 19% A. fluviatilis. Aedes aegypti immatures were found in both urban and rural sites. However, the mean number of A. aegypti pupae was five times higher in containers in the urban sites compared to those in the rural sites. One of the important factors associated with A. aegypti infestation was frequency of container washing. Monthly-washed or never-washed containers were both about four times more likely to be infested than those washed every week. There were no significant differences between urban and rural sites in frequency of washing containers. Aedes aegypti immature infestation was positively associated with total dissolved solids, but negatively associated with dissolved oxygen. Water temperature, total dissolved solids, ammonia, nitrate, and organic matter were significantly higher in urban than in rural containers, which might explain urban-rural differences in breeding of A. aegypti. However, many of these factors vary substantially between studies and in their degree of association with vector breeding, therefore they may not be reliable indices for vector control interventions. Although containers in urban areas

Larvicidal activity of Cybistax antisyphilitica against Aedes aegypti larvae.

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Rodrigues, A M S; de Paula, J E; Roblot, F; Fournet, A; Espíndola, L S

2005-12-01

The larvicidal activity against Aedes aegypti larvae of a stem wood hexane extract of Cybistax antisyphilitica was evaluated. Bioassay-guided fractionation of the crude extract, monitored by larvicidal assay, led to the isolation of a natural quinone identified as 2-hydroxy-3-(3-methyl-2-butenyl)-1.4-naphthoquinone (lapachol). This compound was quite potent against A. aegypti larvae (LC50 26.3 microg/ml).

Updated Reported Distribution of Aedes (Stegomyia) aegypti and Aedes (Stegomyia) albopictus (Diptera: Culicidae) in the United States, 1995-2016.

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Hahn, Micah B; Eisen, Lars; McAllister, Janet; Savage, Harry M; Mutebi, John-Paul; Eisen, Rebecca J

2017-09-01

Aedes (Stegomyia) aegypti (L.) and Aedes (Stegomyia) albopictus (Skuse) are potential vectors of Zika, dengue, and chikungunya viruses in the United States. A Zika virus outbreak in Florida in the summer of 2016, driven by Ae. aegypti and resulting in > 200 locally acquired cases of human illness, underscored the need for up-to-date information on the geographic distribution of Ae. aegypti and Ae. albopictus in the United States. In early 2016, we conducted a survey and literature review to compile county records for presence of Ae. aegypti and Ae. albopictus in the United States from 1995 to 2016. Surveillance for these vectors was intensified across the United States during the summer and fall of 2016. At the end of 2016, we therefore conducted a follow-up survey of mosquito control agencies, university researchers, and state and local health departments to document new collection records for Ae. aegypti and Ae. albopictus. The repeated survey at the end of the year added Ae. aegypti collection records from 38 new counties and Ae. albopictus collection records from 127 new counties, representing a 21 and 10 percent increase, respectively, in the number of counties with reported presence of these mosquitoes compared with the previous report. Moreover, through our updated survey, 40 and 183 counties, respectively, added additional years of collection records for Ae. aegypti and Ae. albopictus from 1995 to 2016. Our findings underscore the continued need for systematic surveillance of Ae. aegypti and Ae. albopictus. Published by Oxford University Press on behalf of Entomological Society of America 2017. This work is written by US Government employees and is in the public domain in the US.

Soil application of formulated Metarhizium brunneum F52 (Hypocreales: Clavicipitaceae) containing microsclerotia controls eggs of Aedes aegypti (Diptera: Culicidae)

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We evaluated the potential of a granular formulation of Metarhizium brunneum F52 containing microsclerotia (MbMSc granules) for control of Aedes aegypti (L.) by targeting eggs. MbMSc granules produced infective conidia within 14 days after application to moist potting soil, producing 5.9 × 10**5, 2....

Knockdown resistance (kdr) of the voltage-gated sodium channel gene of Aedes aegypti population in Denpasar, Bali, Indonesia.

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Hamid, Penny Humaidah; Prastowo, Joko; Widyasari, Anis; Taubert, Anja; Hermosilla, Carlos

2017-06-05

Aedes aegypti is the main vector of several arthropod-borne viral infections in the tropics profoundly affecting humans, such as dengue fever (DF), West Nile (WN), chikungunya and more recently Zika. Eradication of Aedes still largely depends on insecticides, which is the most cost-effective strategy, and often inefficient due to resistance development in exposed Aedes populations. We here conducted a study of Ae. aegypti resistance towards several insecticides regularly used in the city of Denpasar, Bali, Indonesia. Aedes aegypti egg samples were collected with ovitraps and thereafter hatched in the insectary of the Gadjah Mada University. The F0 generation was used for all bioassay-related experiments and knockdown resistance (kdr) assays. Results clearly showed resistance development of Ae. aegypti against tested insecticides. Mortalities of Ae. aegypti were less than 90% with highest resistance observed against 0.75% permethrin. Mosquitoes from the southern parts of Denpasar presented high level of resistance pattern in comparison to those from the western and northern parts of Denpasar. Kdr analysis of voltage-gated sodium channel (Vgsc) gene showed significant association to S989P and V1016G mutations linked to resistance phenotypes against 0.75% permethrin. Conversely, Ae. aegypti F1534C gene mutation did not result in any significant correlation to resistance development. Periodically surveillance of insecticide resistances in Ae. aegypti mosquitoes will help local public health authorities to set better goals and allow proper evaluation of on-going mosquito control strategies. Initial detection of insecticide resistance will contribute to conduct proper actions in delaying mosquito resistance development such as insecticide rotation or combination of compounds in order to prolong chemical efficacy in combating Ae. aegypti vectors in Indonesia.

PENGENDALIAN JENTIK Aedes Aegypti MENGGUNAKAN Mesocyclops Aspericomis MELALUI PARTISIPASI MASYARAKAT

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Umi Widyastuti

2012-07-01

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

Susceptibility status of Aedes aegypti (L.) (Diptera: Culicidae) to temephos in Venezuela.

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Alvarez, Leslie C; Ponce, Gustavo; Oviedo, Milagros; Lopez, Beatriz; Flores, Adriana E

2014-08-01

Temephos is an insecticide widely used in Venezuela to control the proliferation of the larvae of Aedes aegypti (L.), the principal vector of dengue virus. The aim of this study was to identify the susceptibility to temephos of Ae. aegypti in four locations in western Venezuela: Lara, Tres Esquinas, Ureña and Pampanito. Larval bioassays were conducted on samples collected in 2008 and 2010, and the levels of α- and β-esterases, mixed-function oxidases, glutathione-S-transferase and insensitive acethyl cholinesterase were determined. Larval populations from western Venezuela obtained during 2008 and 2010 were found to be susceptible to temephos, with low resistance ratios and without overexpression of enzymes. The low RR values reveal the effectiveness of temephos in controlling the larval populations of Ae. aegypti. Control strategies must be vigorously monitored to maintain the susceptibility to temephos of these populations of Ae. aegypti. © 2013 Society of Chemical Industry.

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

Control of Aedes aegypti larvae in household water containers by Chinese cat fish.

Science.gov (United States)

Wu, N; Wang, S S; Han, G X; Xu, R M; Tang, G K; Qian, C

1987-01-01

In 1980-81 an outbreak of dengue fever occurred in Guangdong province and in Guangxi-Zhuang autonomous region in the central-southern part of China. Subsequently, a nationwide survey indicated that the vector of the disease, Aedes aegypti, was confined to the coastal strip of Guangdong and Guangxi-Zhuang. Since the first case in the outbreak occurred in Guangxi-Zhuang, a community-based programme to control A. aegypti was set up in eight fishing villages of this region where the mosquito was breeding in household water containers. The principal method of control was use of the indigenous edible fish Clarias fuscus (Chinese cat fish), which is highly larvivorous and tolerant of harsh environmental conditions. Each container was stocked with a young fish, which could survive there for periods of up to a year. A team of primary medical personnel (barefoot doctors) made sure that the programme was correctly implemented. The programme was monitored from 1981 to 1985 in three of the villages, and the results indicated that the Breteau index remained at a low level throughout this period.

Complement-related proteins control the flavivirus infection of Aedes aegypti by inducing antimicrobial peptides.

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Xiaoping Xiao

2014-04-01

Full Text Available The complement system functions during the early phase of infection and directly mediates pathogen elimination. The recent identification of complement-like factors in arthropods indicates that this system shares common ancestry in vertebrates and invertebrates as an immune defense mechanism. Thioester (TE-containing proteins (TEPs, which show high similarity to mammalian complement C3, are thought to play a key role in innate immunity in arthropods. Herein, we report that a viral recognition cascade composed of two complement-related proteins limits the flaviviral infection of Aedes aegypti. An A. aegypti macroglobulin complement-related factor (AaMCR, belonging to the insect TEP family, is a crucial effector in opposing the flaviviral infection of A. aegypti. However, AaMCR does not directly interact with DENV, and its antiviral effect requires an A. aegypti homologue of scavenger receptor-C (AaSR-C, which interacts with DENV and AaMCR simultaneously in vitro and in vivo. Furthermore, recognition of DENV by the AaSR-C/AaMCR axis regulates the expression of antimicrobial peptides (AMPs, which exerts potent anti-DENV activity. Our results both demonstrate the existence of a viral recognition pathway that controls the flaviviral infection by inducing AMPs and offer insights into a previously unappreciated antiviral function of the complement-like system in arthropods.

Impact of Tolypocladium cylindrosporum (Hypocreales: Ophiocordycipitaceae) on eggs of Aedes aegypti and Aedes albopictus at low temperature

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We examined the potential of Tolypocladium cylindrosporum IBT 41712 to infect eggs of Aedes aegypti Linnaeus and Aedes albopictus (Skuse) mosquitoes at low temperature (15 deg C). To determine the optimum temperature for the fungus, we cultured the fungus at eight temperatures (4, 12, 15, 21, 28, 33...

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

Science.gov (United States)

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

2014-10-01

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.

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 surpassed the proof of principle stage and is now utilized 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).

Estratégias de controle do Aedes aegypti: uma revisão

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Ana Laura de Sene Amâncio Zara

Full Text Available Resumo OBJETIVO: descrever as principais estratégias de controle do Aedes aegypti, com ênfase nas inovações tecnológicas promissoras para utilização no Brasil. MÉTODOS: trata-se de estudo de revisão não sistemática da literatura. RESULTADOS: diversas tecnologias têm sido desenvolvidas como alternativas no controle do Ae. aegypti, utilizando-se diferentes mecanismos de ação - como monitoramento seletivo da infestação, medidas sociais, dispersão de inseticidas, novos agentes de controle biológico e técnicas moleculares para controle populacional dos mosquitos -, considerando-se também a combinação entre elas. As tecnologias em desenvolvimento demandam avaliação da eficácia, viabilidade e custos para implementação como estratégias complementares às ações já preconizadas pelo Programa Nacional de Controle da Dengue. CONCLUSÃO: a integração de diferentes estratégias de controle vetorial compatíveis e eficazes, considerando as tecnologias disponíveis e as características regionais, parece ser um método viável para tentar reduzir a infestação dos mosquitos e a incidência das arboviroses transmitidas por eles.

Efficacy of topical permethrin as repellent against Aedes aegypti's bites.

Science.gov (United States)

Miot, Hélio Amante; Ferreira, Daniela Pinho; Mendes, Fabiana Guandalini; Carrenho, Flávia Roberta Hernandes; de Oliveira Amui, Isabela; Carneiro, Carlos Augusto Sá; Madeira, Newton Goulart

2008-07-15

Mosquitoes are the most important vectors of infectious diseases and their bites are related to several adverse skin reactions. Permethrin impregnated clothes are an efficient strategy against arthropods' bites; however, its topical efficacy as a repellent has not been well established. We studied the response to permethrin lotion 5 percent and N,N-Diethyl-meta-toluamide (DEET) spray 50 percent applied to the unprotected forearms of 10 volunteers. Each arm was exposed to 20 female mosquitoes of Aedes aegypti. We performed 71 bilateral comparative measurements evaluating the timing for the first bites. The average times for the arm without the product, with permethrin 5 percent, and with DEET 50 percent were: 7.9 seconds, 336.2 seconds and 7512.1 seconds. The results showed a significant difference between repellency times between either product and unprotected controls. In addition, there was a significant difference in time to first bite between permethrin and DEET treated arms (pAedes aegypti bites in this experimental setting. However, permethrin's profile of repellency was significantly inferior to that of DEET.

Larval development of Aedes aegypti and Aedes albopictus in peri-urban brackish water and its implications for transmission of arboviral diseases.

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Ranjan Ramasamy

2011-11-01

Full Text Available Aedes aegypti (Linnaeus and Aedes albopictus Skuse mosquitoes transmit serious human arboviral diseases including yellow fever, dengue and chikungunya in many tropical and sub-tropical countries. Females of the two species have adapted to undergo preimaginal development in natural or artificial collections of freshwater near human habitations and feed on human blood. While there is an effective vaccine against yellow fever, the control of dengue and chikungunya is mainly dependent on reducing freshwater preimaginal development habitats of the two vectors. We show here that Ae. aegypti and Ae. albopictus lay eggs and their larvae survive to emerge as adults in brackish water (water with 30 ppt salt are termed fresh, brackish and saline respectively. Brackish water with salinity of 2 to 15 ppt in discarded plastic and glass containers, abandoned fishing boats and unused wells in coastal peri-urban environment were found to contain Ae. aegypti and Ae. albopictus larvae. Relatively high incidence of dengue in Jaffna city, Sri Lanka was observed in the vicinity of brackish water habitats containing Ae. aegypti larvae. These observations raise the possibility that brackish water-adapted Ae. aegypti and Ae. albopictus may play a hitherto unrecognized role in transmitting dengue, chikungunya and yellow fever in coastal urban areas. National and international health authorities therefore need to take the findings into consideration and extend their vector control efforts, which are presently focused on urban freshwater habitats, to include brackish water larval development habitats.

Heat Sensitivity of wMel Wolbachia during Aedes aegypti Development.

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Jill N Ulrich

2016-07-01

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

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

Science.gov (United States)

Misni, Norashiqin; Othman, Hidayatulfathi; Sulaiman, Sallehudin

2011-08-01

The bioefficacy of Piper aduncum L. essential oil formulated in aerosol cans was evaluated against Aedes aegypti and Aedes albopictus in a simulated room. The aerosol spray test was based on the Malaysian test standard for aerosol (MS 1221:1991UDC 632.982.2 modified from WHO 2009 methodology) and examined the knockdown effect within 20 minutes of exposure. Mortality rate after 24 hour of holding period was also determined. A commercial aerosol spray (0.09% prallethrin 0.05% d-phenothrin) was also tested as a comparison. Our results showed that the knockdown effect of the commercial aerosol spray and P. aduncum essential oil spray (8% and 10% concentrations) was significantly higher in Ae. albopictus adult females, when compared with that of Ae. aegypti adult females (P<0.05). There was a significant difference in knockdown between commercial aerosol spray and essential oil spray for both Aedes spp. (P<0.05). The essential oil induced significantly higher mortality in Ae. aegypti (80%) than in Ae. albopictus (71.6%) (P<0.05). The commercial aerosol spray caused 97.7% and 86.5% mortality against Ae. aegypti and Ae. albopictus respectively (P<0.05). Based on these data, P. aduncum essential oil has the potential to be used as an aerosol spray against Aedes spp.

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

KAUST Repository

Parshad, Rana; Agusto, Folashade B.

2011-01-01

In this paper we study the long time dynamics of a reaction diffusion system, describing the spread of Aedes aegypti mosquitoes, which are the primary cause of dengue infection. The system incorporates a control attempt via the sterile insect

TRANSMISI TRANSOVARIAL VIRUS DENGUE PADA TELUR NYAMUK AEDES AEGYPTI(L.

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Magdalena Desiree Seran

2013-03-01

Full Text Available Abstract. The ability of dengue virus to maintain its existence in nature through two mechanisms, both horizontal and vertical transmission (transovarial of the infective female mosquitoes to the next generation. This study aims to investigate the transovarial transmission and transovarial infection rate (TIR of dengue virus in eggs Aedes aegypti infected mother has a peroral virus DEN-2. This study is an experimental study in the laboratory. The population of the study was Ae. aegypti adults who have previously been infected with DEN-2 virus orally and proved to be infected with DEN-2 transovarially (Fl. The research sample was egg of Ae. aegypti from F2 generation which colonized from DEN-2 transovarially infected Ae. aegypti (Fl. Egg squash preparations made as many as 50 samples from jive difJerent mosquito parents. The presence of dengue virus antigen in mosquitoes FO and Fl were checked by SPBC immunocytochemistry method and using monoclonal antibodies DSSC7 (l: 50 as standardized primary antibodies. The results shows the existence of transovarial transmission of dengue virus in eggs Ae. aegypti (F2 were seen in squash preparations in the form of a brownish color egg spread on embryonic tissues (TIR= 52%. It concludes that dengue virus is able to be transmitted vertically through the egg. Keywords: transovarial transmission, eggsquash, Aedes aegypti, transovarial infection rate (TIR Abstrak. Kemampuan virus dengue untuk mempertahankan keberadaanya di alam dilakukan melalui dua mekanisme yaitu transmisi horizontal dan dengan transmisi vertikal (transovarial yaitu dari nyamuk betina infektif ke generasi berikutnya. Penelitian ini bertujuan untuk mengetahui adanya transmisi transovarial dan transovarial infection rate (TIR virus dengue pada telur Ae. aegypti yang induknya telah diinfeksi virus DEN-2 secara peroraI. Penelitian merupakan jenis penelitian eksperimental di laboratorium. Populasi penelitian adalah Ae. aegypti betina dewasa yang

OVIPOSITION PREFERENCE OF Aedes aegypti AGAINST VARIOUS LEAF EXTRACT AS AN ATRACTANT

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Sara Gustia Wibowo

2015-07-01

Full Text Available Aedes aegypti merupakan vektor pembawa virus Dengue yang menyebabkan penyakit Demam Berdarah Dengue (DBD.Pengendalian secara alami menggunakan bahan nabati merupakan alternatif pengendalian yang ramah lingkungan. Salahsatu pengendalian secara alami adalah memodifikasi ovitrap dengan penambahan zat aktif nabati sebagai atraktan untukmenarik nyamuk bertelur dan dapat menjadi ovisida dan larvasida. Tujuan penelitian ini adalah mengetahui preferensibertelurnya nyamuk Ae. aegypti pada ovitrap dengan ekstrak daun mimba (Azadirachta indica, kecubung (Datura metel,zodia (Evodia suavolens dan jenu (Derris elliptica. Jenis penelitian eksperimen dengan rancangan acak lengkap. Keempatjenis ekstrak daun tersebut diisiikan pada ovitrap, dimasukan ke dalam kandang yang berisi 30 ekor Ae. aegypti dengankondisi kenyang darah. Pengamatan dilakukan setiap hari sampai hari ke-3. Hasil uji preferensi berbagai jenis ekstrak inimenunjukkan ovitrap yang berisi ekstrak daun jenu (D. elliptica lebih banyak ditemukan telur Ae. aegypti dibandingkandengan kontrol maupun ovitrap dengan ekstrak daun lainnya. Persentase telur pada kontainer dengan ekstrak jenu adalah44,2%, sedangkan yang terkecil ekstrak zodia (E. suaveolans 9,2%. Hasil uji Anova menunjukkan bahwa perlakuan antarkelompok berbeda nyata (p=0,000. Tanaman jenu (D. elliptica mempunyai potensi sebagai atraktan terhadap nyamuk Ae.aegypti dalam proses oviposisi.Kata kunci: atraktan, oviposisi, jenu (Derris elliptica, Aedes aegypti

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

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

2016-07-01

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.

EKSISTENSI DAN SEBARAN NYAMUK AEDES AEGYPTI DAN AEDES ALBOPICTUS DI KAMPUS UNIVERSITAS HASANUDDIN MAKASSAR

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Yosefina Dota T

2015-03-01

Full Text Available Penelitian yang bertujuan untuk mengetahui eksistensi dan sebaran nyamuk Aedes aegypti dan Aedes albopictus telah dilakukan di Kampus Universitas Hasanuddin, Kec. Tamalanrea, Makassar. Penelitian bersifat eksploratif dengan melakukan sampling terhadap lima lokasi yaitu : a Fak. Peternakan (Utara, b Fak. Hukum (Timur, c Pusat Kegiatan Penelitian/PKP (Selatan, d Workshop/Dekat Pondokan mahasiswa (Barat dan e Fak. MIPA (Tengah. Sampling nyamuk menggunakan metode ovitrap (menggunakan attraktan Eluisine Indica L. dan survei terhadap berbagai tempat penampungan air. Sampel telur dan larva nyamuk yang diperoleh disimpan dalam microtube berisi alkohol 70% kemudian diidentifikasi berdasarkan Rueda (2004. Hasil penelitian menunjukkan bahwa Nyamuk Ae. aegypti dan Ae. albopictus ditemukan hidup dan berkembang biak di kampus Universitas Hasanuddin, Makassar. Eksistensi dan sebaran kedua jenis nyamuk tersebut dipengaruhi oleh faktor adanya manusia/masyarakat kampus yang beraktivitas baik di dalam ruangan (indoor maupun di luar ruangan (outdoor, adanya berbagai tempat penampungan air baik buatan (bak mandi, ember maupun barang bekas (botol/kaleng bekas, tempurung kelapa, vegetasi/tanaman dan berbagai macam hewan yang berada di sekitaran kampus. Hasil penelitian dalam ruangan (indoor menunjukkan bahwa nyamuk Ae. aegypti lebih banyak ditemukan hidup di dalam ruangan gedung PKP sedangkan Ae.albopictus lebih banyak di Fak. Hukum. Hasil penelitian di luar ruangan (outdoor menunjukkan bahwa nyamuk Ae. aegypti lebih banyak ditemukan hidup di area Workshop sedangkan Ae.albopictus lebih banyak di area PKP.

Toksisitas Insektisida Organofosfat Dan Karbamat Terhadap Nyamuk Aedes aegypti

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Endang Puji Astuti

2013-02-01

Full Text Available Abstract. Aedes aegypti mosquito is increasing problem of public health, being the vector responsible for Dengue and Chikungunya. Chlorpirifos (Organofosfat and Metonil (Carbamate were known to posses insecticide activity against insect. The study was aimed to examine effectiveness of Chlorpirifos and Metonil as insectiside against Ae. aegypti mos­quito Chlorpirifos a significantly higher insecticide activity against Ae. aegypti_than Metonil. The mosquito mortality was observed after 24 h exposure. The LCso value of Chlor­pirifos and Metonil were 0.64 mg/lt and 0,802 mg/lt, against Ae. aegypti mosquito. The mixed of both insecticide was LCso value 108.04 mg/lt, this result prove that mixed of both insecticede not sinergism. The result of th is study suggested that Chlorpirifos more effective insecticide against Ae. aegypti than Metonil. Key Words : Culex quinquefasciatus, insecticide, chlorpirifos, metonil

Co-occurrence of point mutations in the voltage-gated sodium channel of pyrethroid-resistant Aedes aegypti populations in Myanmar.

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Kawada, Hitoshi; Oo, Sai Zaw Min; Thaung, Sein; Kawashima, Emiko; Maung, Yan Naung Maung; Thu, Hlaing Myat; Thant, Kyaw Zin; Minakawa, Noboru

2014-01-01

Single amino acid substitutions in the voltage-gated sodium channel associated with pyrethroid resistance constitute one of the main causative factors of knockdown resistance in insects. The kdr gene has been observed in several mosquito species; however, point mutations in the para gene of Aedes aegypti populations in Myanmar have not been fully characterized. The aim of the present study was to determine the types and frequencies of mutations in the para gene of Aedes aegypti collected from used tires in Yangon City, Myanmar. We determined high pyrethroid resistance in Aedes aegypti larvae at all collection sites in Yangon City, by using a simplified knockdown bioassay. We showed that V1016G and S989P mutations were widely distributed, with high frequencies (84.4% and 78.8%, respectively). By contrast, we were unable to detect I1011M (or I1011V) or L1014F mutations. F1534C mutations were also widely distributed, but with a lower frequency than the V1016G mutation (21.2%). High percentage of co-occurrence of the homozygous V1016G/S989P mutations was detected (65.7%). Additionally, co-occurrence of homozygous V1016G/F1534C mutations (2.9%) and homozygous V1016G/F1534C/S989P mutations (0.98%) were detected in the present study. Pyrethroid insecticides were first used for malaria control in 1992, and have since been constantly used in Myanmar. This intensive use may explain the strong selection pressure toward Aedes aegypti, because this mosquito is generally a domestic and endophagic species with a preference for indoor breeding. Extensive use of DDT for malaria control before the use of this chemical was banned may also explain the development of pyrethroid resistance in Aedes aegypti.

Co-occurrence of Point Mutations in the Voltage-Gated Sodium Channel of Pyrethroid-Resistant Aedes aegypti Populations in Myanmar

Science.gov (United States)

Kawada, Hitoshi; Oo, Sai Zaw Min; Thaung, Sein; Kawashima, Emiko; Maung, Yan Naung Maung; Thu, Hlaing Myat; Thant, Kyaw Zin; Minakawa, Noboru

2014-01-01

Background Single amino acid substitutions in the voltage-gated sodium channel associated with pyrethroid resistance constitute one of the main causative factors of knockdown resistance in insects. The kdr gene has been observed in several mosquito species; however, point mutations in the para gene of Aedes aegypti populations in Myanmar have not been fully characterized. The aim of the present study was to determine the types and frequencies of mutations in the para gene of Aedes aegypti collected from used tires in Yangon City, Myanmar. Methodology/Principal Findings We determined high pyrethroid resistance in Aedes aegypti larvae at all collection sites in Yangon City, by using a simplified knockdown bioassay. We showed that V1016G and S989P mutations were widely distributed, with high frequencies (84.4% and 78.8%, respectively). By contrast, we were unable to detect I1011M (or I1011V) or L1014F mutations. F1534C mutations were also widely distributed, but with a lower frequency than the V1016G mutation (21.2%). High percentage of co-occurrence of the homozygous V1016G/S989P mutations was detected (65.7%). Additionally, co-occurrence of homozygous V1016G/F1534C mutations (2.9%) and homozygous V1016G/F1534C/S989P mutations (0.98%) were detected in the present study. Conclusions/Significance Pyrethroid insecticides were first used for malaria control in 1992, and have since been constantly used in Myanmar. This intensive use may explain the strong selection pressure toward Aedes aegypti, because this mosquito is generally a domestic and endophagic species with a preference for indoor breeding. Extensive use of DDT for malaria control before the use of this chemical was banned may also explain the development of pyrethroid resistance in Aedes aegypti. PMID:25077956

Active metabolites of the genus Piper against Aedes aegypti: natural alternative sources for dengue vector control

OpenAIRE

Marques, André M; Kaplan, Maria Auxiliadora C

2015-01-01

The mosquito, Aedes aegypti, is the principal vector of the viruses responsible for dengue and dengue hemorrhagic fevers. The mosquito is widespread throughout tropical and sub-tropical regions; its prevalence makes dengue one of the most important mosquito-borne viral diseases in the world occurring annually in more than 100 endemic countries. Because blood is essential to their development cycle, the Aedes species maintains a close association with humans and their dwellings. Fittingly, the...

Susceptibility of Aedes aegypti pupae to neem seed kernal extracts ...

African Journals Online (AJOL)

Azadirachta indica) seed kernel extracts (NSKE) on Aedes aegypti. The neem seed kernel powder was sequentially extracted with hexane, benzene, ethyl acetate, acetone, DMSO, 2-propanol, ethanol, methanol and dstiledwater.

Community-Based Control of Aedes aegypti By Using Mesocyclops in Southern Vietnam

Science.gov (United States)

Nam, Vu Sinh; Yen, Nguyen Thi; Duc, Hoang Minh; Tu, Tran Cong; Thang, Vu Trong; Le, Nguyen Hoang; San, Le Hoang; Loan, Luu Le; Huong, Vu Thi Que; Khanh, Ly Huynh Kim; Trang, Huynh Thi Thuy; Lam, Leonie Z. Y.; Kutcher, Simon C.; Aaskov, John G.; Jeffery, Jason A. L.; Ryan, Peter A.; Kay, Brian H.

2012-01-01

We previously reported a new community-based mosquito control strategy that resulted in elimination of Aedes aegypti (Linn.) in 40 of 46 communes in northern and central Vietnam, and with annual recurrent total costs (direct and indirect) of only $0.28–$0.89 international dollars per person. This control strategy was extended to four provinces in southern Vietnam in Long An and Hau Giang (2004–2007) and to Long An, Ben Tre, and Vinh Long (2005–2010). In a total of 14 communes with 124,743 residents, the mean ± SD of adult female Ae. aegypti was reduced from 0.93 ± 0.62 to 0.06 ± 0.09, and the reduction of immature Ae. aegypti averaged 98.8%. By the final survey, no adults could be collected in 6 of 14 communes, and one commune, Binh Thanh, also had no immature forms. Although the community-based programs also involved community education and clean-up campaigns, the prevalence of Mesocyclops in large water storage containers > 50 liters increased from 12.77 ± 8.39 to 75.69 ± 9.17% over periods of 15–45 months. At the conclusion of the study, no confirmed dengue cases were detected in four of the five communes for which diagnostic serologic analysis was performed. The rate of progress was faster in communes that were added in stages to the program but the reason for this finding was unclear. At the completion of the formal project, sustainability funds were set up to provide each commune with the financial means to ensure that community-based dengue control activities continued. PMID:22556087

Toxicity of spinosad to temephos-resistant Aedes aegypti populations in Brazil

Science.gov (United States)

dos Santos Dias, Luciana; Macoris, Maria de Lourdes da Graça; Andrighetti, Maria Teresa Macoris; Otrera, Vanessa Camargo Garbeloto; Dias, Adriana dos Santos; Bauzer, Luiz Guilherme Soares da Rocha; Rodovalho, Cynara de Melo; Martins, Ademir Jesus; Lima, José Bento Pereira

2017-01-01

The mosquito Aedes aegypti is the primary vector of different arboviruses and represents a major public health problem. Several Brazilian populations of Ae. aegypti have developed resistance to temephos, the most used organophosphate larvicide. New tools which are less harmful to the environment and safer for humans are becoming increasingly important to control this insect vector. Spinosad, an aerobic fermentation product of a soil actinobacteria, has a favorable environmental profile. It presents selective insecticide properties, a mechanism of action that differs from those of many synthetic chemical insecticides. The toxicity of spinosad and temephos to Aedes aegypti populations from Brazil, which were previously exposed to temephos, were investigated in this study. Larval susceptibility (LC50) to temephos varied from 3μg/L for Rockefeller up to 260 μg/L for Santana do Ipanema field derived population. Larval susceptibility (LC50) to spinosad varied from 23μg/L for Rockefeller up to 93μg/L for Marilia field derived population. In addition, a semi-field trial was performed to evaluate spinosad (NatularTM DT) initial efficacy and persistence toward four field-derived lineages and the Rockefeller lineage, used as an internal control. Spinosad was tested at 0.5mg active ingredient/L in 200L capacity water tanks. Mortality was recorded each 24 hours after exposition and tanks were further recolonized once per week with mortality being recorded daily for eight weeks. Spinosad provided a level equal or superior to 80% mortality during a seven to eight week evaluation period. The assessed populations did not present cross-resistance between spinosad and temephos in laboratory conditions. It demonstrates that spinosad may be a promising larvicide for the control of Ae. aegypti, especially for populations in which resistance to temephos has been detected. PMID:28301568

Toxicity of spinosad to temephos-resistant Aedes aegypti populations in Brazil.

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Luciana Dos Santos Dias

Full Text Available The mosquito Aedes aegypti is the primary vector of different arboviruses and represents a major public health problem. Several Brazilian populations of Ae. aegypti have developed resistance to temephos, the most used organophosphate larvicide. New tools which are less harmful to the environment and safer for humans are becoming increasingly important to control this insect vector. Spinosad, an aerobic fermentation product of a soil actinobacteria, has a favorable environmental profile. It presents selective insecticide properties, a mechanism of action that differs from those of many synthetic chemical insecticides. The toxicity of spinosad and temephos to Aedes aegypti populations from Brazil, which were previously exposed to temephos, were investigated in this study. Larval susceptibility (LC50 to temephos varied from 3μg/L for Rockefeller up to 260 μg/L for Santana do Ipanema field derived population. Larval susceptibility (LC50 to spinosad varied from 23μg/L for Rockefeller up to 93μg/L for Marilia field derived population. In addition, a semi-field trial was performed to evaluate spinosad (NatularTM DT initial efficacy and persistence toward four field-derived lineages and the Rockefeller lineage, used as an internal control. Spinosad was tested at 0.5mg active ingredient/L in 200L capacity water tanks. Mortality was recorded each 24 hours after exposition and tanks were further recolonized once per week with mortality being recorded daily for eight weeks. Spinosad provided a level equal or superior to 80% mortality during a seven to eight week evaluation period. The assessed populations did not present cross-resistance between spinosad and temephos in laboratory conditions. It demonstrates that spinosad may be a promising larvicide for the control of Ae. aegypti, especially for populations in which resistance to temephos has been detected.

The global compendium of Aedes aegypti and Ae. albopictus occurrence

Science.gov (United States)

Kraemer, Moritz U. G.; Sinka, Marianne E.; Duda, Kirsten A.; Mylne, Adrian; Shearer, Freya M.; Brady, Oliver J.; Messina, Jane P.; Barker, Christopher M.; Moore, Chester G.; Carvalho, Roberta G.; Coelho, Giovanini E.; van Bortel, Wim; Hendrickx, Guy; Schaffner, Francis; Wint, G. R. William; Elyazar, Iqbal R. F.; Teng, Hwa-Jen; Hay, Simon I.

2015-07-01

Aedes aegypti and Ae. albopictus are the main vectors transmitting dengue and chikungunya viruses. Despite being pathogens of global public health importance, knowledge of their vectors’ global distribution remains patchy and sparse. A global geographic database of known occurrences of Ae. aegypti and Ae. albopictus between 1960 and 2014 was compiled. Herein we present the database, which comprises occurrence data linked to point or polygon locations, derived from peer-reviewed literature and unpublished studies including national entomological surveys and expert networks. We describe all data collection processes, as well as geo-positioning methods, database management and quality-control procedures. This is the first comprehensive global database of Ae. aegypti and Ae. albopictus occurrence, consisting of 19,930 and 22,137 geo-positioned occurrence records respectively. Both datasets can be used for a variety of mapping and spatial analyses of the vectors and, by inference, the diseases they transmit.

Contact Irritant Responses of Aedes aegypti Using Sublethal Concentration and Focal Application of Pyrethroid Chemicals

OpenAIRE

Manda, Hortance; Shah, Pankhil; Polsomboon, Suppaluck; Chareonviriyaphap, Theeraphap; Castro-Llanos, Fanny; Morrison, Amy; Burrus, Roxanne G.; Grieco, John P.; Achee, Nicole L.

2013-01-01

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: Cont...

Potential for dengue in South Africa: mosquito ecology with particular reference to Aedes aegypti.

Science.gov (United States)

Kemp, A; Jupp, P G

1991-12-01

Observations on prevalence, geographical distribution, utilization of artificial larval habitats and anthropophilism were made on diurnal mosquitoes at selected localities along the coast of Natal and inland in the Transvaal to identify potential vectors of dengue in South Africa. Larval collections made in artificial containers on the ground, the exposure of bamboo pots as ovitraps in trees and collection of mosquitoes biting man showed the following species as the most likely candidates for vectors: Aedes aegypti, Ae. demeilloni, Ae. simpsoni, Ae. strelitziae, Ae. furcifer, Ae. cordellieri and Eretmapodites quinquevittatus. The bamboo pots showed that Ae. aegypti and Ae. simpsoni were the most widespread species, occurring at 11 of 12 localities. Aedes aegypti was the most prevalent species with mean pot index of 60.3 +/- 9.8% (SE) and abundance index of 0.43 +/- 0.15 (SE). Aedes aegypti was frequently present as larvae in artificial containers at indices of 11-83% (mean 56.8 +/- 5.6%, SE) and was the most anthropophilic species with average biting rates of 10-29 per man-hour at 7 localities. Although Ae. aegypti was abundant in the pots at Ndumu (northern Natal) and at Skukuza (eastern Transvaal), the local populations were poorly anthropophilic at these localities. At some localities, populations of Ae. demeilloni, Ae. simpsoni and Ae. strelitziae had average biting rates of 5.4-9.6 per man-hour. Aedes furcifer was collected for the first time at Durban, extending its distribution southward to latitude 29 degrees 53' S.

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

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Dyah Widiastuti

2015-06-01

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

Characterization of Tolypocladium cylindrosporum (Hypocreales: Ophiocordycipitacea) and its impact against Aedes aegypti and Aedes albopictus eggs at low temperature

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We examined the growth characteristics of Tolypocladium cylindrosporum IBT 41712 and its potential to infect eggs of Aedes aegypti Linnaeus and Aedes albopictus (Skuse) mosquitoes at low temperature (15 deg C). When grown on sabouraud dextrose agar supplemented with yeast extract, IBT 41712 formed w...

The Aedes aegypti toll pathway controls dengue virus infection.

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Zhiyong Xi

2008-07-01

Full Text Available Aedes aegypti, the mosquito vector of dengue viruses, utilizes its innate immune system to ward off a variety of pathogens, some of which can cause disease in humans. To date, the features of insects' innate immune defenses against viruses have mainly been studied in the fruit fly Drosophila melanogaster, which appears to utilize different immune pathways against different types of viruses, in addition to an RNA interference-based defense system. We have used the recently released whole-genome sequence of the Ae. aegypti mosquito, in combination with high-throughput gene expression and RNA interference (RNAi-based reverse genetic analyses, to characterize its response to dengue virus infection in different body compartments. We have further addressed the impact of the mosquito's endogenous microbial flora on virus infection. Our findings indicate a significant role for the Toll pathway in regulating resistance to dengue virus, as indicated by an infection-responsive regulation and functional assessment of several Toll pathway-associated genes. We have also shown that the mosquito's natural microbiota play a role in modulating the dengue virus infection, possibly through basal-level stimulation of the Toll immune pathway.

Wingbeat frequency-sweep and visual stimuli for trapping male Aedes aegypti (Diptera: Culicidae)

Science.gov (United States)

Combinations of female wingbeat acoustic cues and visual cues were evaluated to determine their potential for use in male Aedes aegypti (L.) traps in peridomestic environments. A modified Centers for Disease control (CDC) light trap using a 350-500 Hz frequency-sweep broadcast from a speaker as an a...

Evaluación del efecto residual del temephos en larvas de Aedes aegypti en Lima, Perú

OpenAIRE

Palomino S, Miriam; Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú.; Solari, Lely; Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú. Hospital Nacional Hipólito Unánue. Lima, Perú.; León C, Walter; Centro Nacional de Salud Pública, Instituto Nacional de Salud. Lima, Perú.; Vega H, Rosario; Centro Nacional de Control de Calidad, Instituto Nacional de Salud. Lima, Perú.; Vergaray C, Máximo; Centro Nacional de Control de Calidad, Instituto Nacional de Salud. Lima, Perú.; Cubillas, Luis; Dirección de Salud Lima Norte III, Ministerio de Salud. Lima, Perú.; Mosqueda C, Rosa; Centro Nacional de Control de Calidad, Instituto Nacional de Salud. Lima, Perú.; García A, Norma; Centro Nacional de Control de Calidad, Instituto Nacional de Salud. Lima, Perú.

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 laborato - rio en Lima, Perú. Materiales y métodos: Se eligieron ocho tanques bajos de concreto (TBC) depósitos predominan - temente 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 ...

Aedes aegypti resistance development to commonly used insecticides in Jakarta, Indonesia.

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Penny Humaidah Hamid

Full Text Available Aedes aegypti is the primary vector of various relevant arthropod-borne viral infectious diseases worldwide. The mosquito control is still mainly performed by using insecticides but their effectiveness is increasingly questioned nowadays. We here conducted a study on Ae. aegypti resistance development towards several commonly used insecticides in the capital city of Jakarta, Indonesia. In order to achieve this goal, Ae. aegypti eggs from Jakarta were collected with ovitraps and hatched in the insectary of the Gadjah Mada University, Indonesia. The F0 generations were used for WHO resistance tests and knockdown resistance (kdr assays. Presented results clearly showed that there was resistance development of Ae. aegypti populations to the here tested pyrethroid insecticides (i. e. permethrin. Observed mortalities were less than 90% with highest resistance against 0.75% permethrin concentrations. Furthermore, a significant association of V1016G gene mutations with resistance phenotypes to 0.75% permethrin was observed. Nevertheless, the F1534C mutation did not show a significant correlation to resistance development. In conclusion, our results show that populations of Ae. aegypti mosquitoes within the city of Jakarta have developed resistance against several routinely used pyrethroid insecticides in local performed control programs. Thus, the regular verification/assessment of resistance development status will hopefully help in the future to assist local public health authorities in their mosquito control programs by recommending and managing the rotation of different routinely used insecticides with diverse effector mechanisms in order to delay Ae. aegypti resistance development.

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.

Maternal invasion history of Aedes aegypti and Aedes albopictus into the Isthmus of Panama: Implications for the control of emergent viral disease agents

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Eskildsen, Gilberto A.; Rovira, Jose R.; Smith, Octavio; Miller, Matthew J.; Bennett, Kelly L.; McMillan, W. Owen

2018-01-01

Despite an increase in dengue outbreaks and the arrival of chikungunya and Zika disease in Panama, studies on the demographic history of the invasive Aedes mosquitoes that are the principle vectors of these diseases are still lacking in this region. Here, we assess the genetic diversity of these mosquitoes in order to decipher their invasion histories into the Isthmus of Panama. DNA sequences from the mitochondrial cytochrome C oxidase I gene obtained from 30 localities in 10 provinces confirmed the presence of more than one mitochondrial haplogroup (i.e., maternal lineage) in each species. The invasion of Aedes albopictus was likely from temperate European countries, as the most frequent and widespread haplogroup in Panama harbored variants that are uncommon elsewhere in the Americas. Two infrequent and geographically restricted Ae. albopictus haplotypes appear to have subsequently invaded Panama from neighboring Costa Rica and the USA, respectively. In addition, we recovered two deeply divergent mitochondrial clades in Panamanian Aedes aegypti. The geographic origins of these clades is unknown, given that divergence in the mitochondrial genome is probably due to ancient population processes within the native range of Ae. aegypti, rather than due to its global expansion out of Africa. However, Panamanian Ae. aegypti mitochondrial sequences within the first clade were closely related to others from Colombia, Bolivia, Brazil, Mexico and the USA, suggesting two separate invasions from Western Hemisphere source populations. The pattern of increased genetic diversity in Aedes mosquitoes in Panama is likely facilitated by the numerous land and water inter-connections across the country, which allows them to enter via sea- and land-transportation from Europe, North, Central and South America. Our results here should be considered in disease mitigation programs if emergent arboviruses are to be effectively diminished in Panama through vector suppression. PMID:29579112

A new tent trap for monitoring the daily activity of Aedes aegypti and Aedes albopictus.

Science.gov (United States)

Casas Martínez, Mauricio; Orozco Bonilla, Arnoldo; Muñoz Reyes, Miguel; Ulloa García, Armando; Bond, J Guillermo; Valle Mora, Javier; Weber, Manuel; Rojas, Julio C

2013-12-01

In this study, we designed a new tent trap; the BioDiVector (BDV) tent trap, consisting of two rectangular tents that use human bait without endangering the technical personnel. The daily activity pattern of Aedes aegypti and Aedes albopictus in intra, peri, and extradomiciliary sites was studied in an endemic area of dengue in southern Mexico by using the BDV tent trap. Totals of 3,128 individuals of Ae. aegypti and 833 Ae. albopictus were captured. More Ae. aegypti males than females were caught, while the opposite was true with Ae. albopictus. The activity of both mosquito species was affected by the interaction between the collection site and time of day. In general, more individuals of both mosquito species were captured at the extradomicillary sites than at the peri and intradomicillary sites. Mosquitoes showed two peaks of activity, one in the morning and the other in the afternoon, but in general this only occurred at the extradomicillary sites, whereas no peak of activity was observed at the intra and peridomicillary sites. Overall, Ae. aegypti had a higher indirect biting rate than Ae. albopictus. Finally, due to its efficiency, simplicity, and low cost, we suggest the use of this innovative tool for entomological surveillance, bionomics and vector incrimination studies in geographical areas where dengue and other arboviruses are present. © 2013 The Society for Vector Ecology.

Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

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Marina Stein

2002-10-01

Full Text Available Se identificaron criaderos de Aedes (Stegomyia aegypti en dos ciudades de la provincia del Chaco (Noreste de Argentina: Presidencia Roque Saenz Peña y Machagai. Los recipientes encontrados en los patios de las viviendas capaces de colectar agua se clasificaron según tipo y tamaño, se contaron y examinaron. Aedes aegypti y Culex quinquefasciatus fueron las especies mas abundantes, encontrándose además Cx. maxi, Cx. saltanensis y Ochlerotatus scapularis. Los neumáticos y cajas de baterías para autos fueron los recipientes que más aportaron a la producción de formas inmaduras de los culícidos colectados. Las lluvias fueron un factor importante para la proliferacion de Ae. aegypti, así como también el habito comun en la población de guardar recipientes en sus casas que permitan el desarrollo de estos culícidos.

Principales criaderos para Aedes aegypti y culícidos asociados, Argentina

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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.

History of domestication and spread of Aedes aegypti - A Review

OpenAIRE

Jeffrey R Powell; Walter J Tabachnick

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 consid...

Hallazgo de mesocyclops aspericornis (Daday) (Copepoda: Cyclopidae) depredador de larvas de aedes aegypti en Anapoima Colombia (1)

OpenAIRE

Marco Fidel Suárez; Dwight Ayala; Michael J. Nelson; Janet W. Reid

1984-01-01

En Anapoima, Colombia, se encontró que el copépodo Mesocyclops aspericornis era depredador de larvas del mosquito Aedes aegypti. Este encuentro representa el primer hallazgo de este copépodo en recipientes artificiales en la región neotropical, y el primer hallazgo como depredador de larvas de Aedes aegypti.

Controlling Aedes aegypti population as DHF vector with radiation based-sterile insect technique in Banjarnegara Regency, Central Java

International Nuclear Information System (INIS)

Siti Nurhayati; Bambang Yunianto; Tri Ramadhani; Bina Ikawati; Budi Santoso; Ali Rahayu

2013-01-01

The control program of dengue hemorrhagic fever (DHF) in Indonesia is still a problem due to the incomplete integrated handling. Sterile insect technique (SIT) for Aedes aegypti as DHF vector was considered as a potential strategy for controlling the DHF. A preliminary survey was carried out to determine the characteristic of A aegypti population in the study site before the implementation of SIT. The implementation of radiation based-SIT was carried out in Krandegan and Kutabanjar Villages of Banjarnegara Regency, Central Java which involved 99 houses. One hundred gamma rays irradiated male mosquitoes were released to each house up to five times. The eggs, larvae and adult mosquitoes were collected using ovitrap and weekly observed. The initial population density of A. aegypti in the studied area was obtained to be 6 mosquitoes per house with the mean index of house was 15.86% and the mean sterility of sterilized mosquitoes was 79.16%. The SIT effectively reduced A. aegypti population after the fifth release of irradiated mosquitoes into the houses. It can be assumed that the SIT was effective in controlling DHF vector in the studied area, nevertheless, it will be more effective if it is combined with other handling techniques. (author)

Invasiveness of Aedes aegypti and Aedes albopictus and Vectorial Capacity for Chikungunya Virus.

Science.gov (United States)

Lounibos, Leon Philip; Kramer, Laura D

2016-12-15

In this review, we highlight biological characteristics of Aedes aegypti and Aedes albopictus, 2 invasive mosquito species and primary vectors of chikungunya virus (CHIKV), that set the tone of these species' invasiveness, vector competence, and vectorial capacity (VC). The invasiveness of both species, as well as their public health threats as vectors, is enhanced by preference for human blood. Vector competence, characterized by the efficiency of an ingested arbovirus to replicate and become infectious in the mosquito, depends largely on vector and virus genetics, and most A. aegypti and A. albopictus populations thus far tested confer vector competence for CHIKV. VC, an entomological analog of the pathogen's basic reproductive rate (R 0 ), is epidemiologically more important than vector competence but less frequently measured, owing to challenges in obtaining valid estimates of parameters such as vector survivorship and host feeding rates. Understanding the complexities of these factors will be pivotal in curbing CHIKV transmission. © The Author 2016. Published by Oxford University Press for the Infectious Diseases Society of America. All rights reserved. For permissions, e-mail journals.permissions@oup.com.

Larvicidal Activity of Silver Nanoparticles Synthesized Using Extracts of Ambrosia arborescens (Asteraceae to Control Aedes aegypti L. (Diptera: Culicidae

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Bianca Morejón

2018-01-01

Full Text Available The mosquito species Aedes aegypti is the primary vector of dengue, chikungunya, and Zika infections worldwide. Since effective vaccines or drugs are not available for the prevention and/or treatment of these pathologies, vector control has been adopted as the main approach to reduce their transmission. To control Aedes populations, the most commonly used tool is the application of chemical insecticides and, despite their effectiveness, indiscriminate use of these chemicals has led to high operational costs, appearance of resistant populations, and adverse nontarget effects. Plant-derived insecticides may be an eco-friendly, cost-effective, and safe biocontrol alternative. The present study was carried out to evaluate the larvicidal activity of leaf extracts of Ambrosia arborescens and green-synthesized silver nanoparticles (AgNPs using aqueous extracts obtained from this plant against third instar larvae of Ae. aegypti. To test this, larvae were exposed for 24 h to the aqueous plant extract at 1500, 3000, 4500, and 6000 ppm and the plant-synthesized AgNPs at 0.2, 0.3, 0.4, and 0.5 ppm. In laboratory assays, AgNPs were more toxic (LC50 = 0.28 ppm; LC90 = 0.43 ppm than the plant extract (LC50 = 1844.61 ppm; LC90 = 6043.95 ppm. These results suggest that A. arborescens aqueous extract and green-synthesized silver nanoparticles produced from those extracts have the potential to be developed into suitable alternative tools useful for the control of Ae. aegypti populations.

Comportamento de formas imaturas de Aedes aegypti, no litoral do Estado de São Paulo

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Carmen Moreno Glasser

2011-06-01

Full Text Available INTRODUÇÃO: Em região de alta incidência de dengue, no litoral do Estado de São Paulo, selecionaram-se 9 áreas, com objetivo de avaliar o comportamento de formas imaturas de Aedes aegypti. MÉTODOS: As 9 áreas foram agrupadas em 4 estratos, diferenciados pelo uso e ocupação do solo. Foram coletadas larvas e pupas numa amostra de cerca de 500 imóveis em cada área. RESULTADOS: Apesar do pneu e lona apresentarem as maiores taxas de positividade para Aedes aegypti, o ralo, juntamente com outros recipientes fixos nas edificações foram altamente predominantes entre os recipientes positivos (32 a 76% dos recipientes positivos. As áreas coletivas de prédios e os imóveis não residenciais de grande porte apresentaram as maiores taxas de positividade para Aedes aegypti enquanto os apartamentos, as menores. Os níveis de infestação foram maiores na área residencial com predominância de prédios de apartamentos, onde 76% dos criadouros detectados foram recipientes fixos nas edificações. CONCLUSÕES: Esses conhecimentos são importantes subsídios para a estratégia de controle, pois reforçam a necessidade de atenção especial para determinados tipos de imóveis, bem como da adequação da norma técnica de ralo de água pluvial e da melhoria de manutenção das edificações. Além disso, são necessárias observações sistemáticas que permitam acompanhar a dinâmica de ocupação de diferentes imóveis e recipientes por Aedes aegypti e a incorporação desses conhecimentos nas ações de controle do vetor na região.

La actividad de control en la lucha contra el Aedes aegypti en el nivel primario de atención The activity of control in the fight against the Aedes aegypti at care primary level

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Vivian de las Mercedes Noriega Bravo

2012-03-01

Full Text Available En el nivel primario de atención, el policlínico lleva a cabo, un conjunto de procesos relacionados con la salud de la población que se originan en las diferentes áreas, departamentos o servicios, tal es el de Higiene y Epidemiología, del cual forma parte el departamento de vigilancia y lucha antivectorial. Las actividades que este realiza no son totalmente independientes, sino que se encuentran conectadas a otras unidades organizativas, lo que amplía la variedad de problemas ligados a la calidad. Los conceptos de gestión y control, bajo la perspectiva de calidad, incluyen la atención a los procesos que resultan clave para un desempeño eficaz de la organización, y descansa entre otros elementos, en la articulación de las acciones necesarias para lograr soluciones pertinentes. El objetivo de este trabajo, es comentar algunas ideas acerca de la actividad de control, al trabajo de vigilancia y lucha contra el Aedes aegypti, que se realiza en el nivel primario de atención de salud.In the care primary level, the polyclinic carry out a group of processes related to the population health from different areas, departments or services including that of Hygiene and Epidemiology, of which is part the surveillance department and anti-vectorial fight widening the variety of problems linked to quality. The concepts of management and control under the health perspective include the attention of the processes being key for an effective performance of the organization and rest among other elements in articulation of the actions needed to achieve appropriate solutions. The objective of present paper is to comment on some ideas about the activity of control of surveillance work and the fight against the Aedes aegypti, performed at primary level of health care.

Field trial on a novel control method for the dengue vector, Aedes aegypti by the systematic use of Olyset® Net and pyriproxyfen in Southern Vietnam

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Tsunoda Takashi

2013-01-01

Full Text Available Abstract Background Jars, tanks, and drums provide favorable rearing/breeding sites for Aedes aegypti in Vietnam. However, the use of insecticides to control mosquitoes at such breeding sites has not been approved in Vietnam since they are also often sources of drinking water, making larval vector control difficult. Mosquito nets pre-treated with long-lasting insecticide treated nets (LLITNs form an effective measure for malaria control. We examined changes in the abundance of immature Aedes aegypti to evaluate the efficacy of covering ceramic jars with lids comprising one type of LLITN, Olyset® Net, in inhibiting oviposition by adult females, and to evaluate the effect of treating other breeding containers, such as flower vases, inside and around the outside of houses with a slow-release pyriproxyfen formulation to kill pupae. Methods We selected 313 households for the trial and 363 households for the control in Tan Chanh, Long An province, Vietnam. In the trial area, Olyset® Net lids were used to cover five major types of water container (ceramic jars, cylindrical concrete tanks, other concrete tanks, plastic drums, and plastic buckets, while pyriproxyfen was used to treat flower vases and ant traps. We also monitored dengue virus transmission by measuring anti-dengue IgM and IgG levels in healthy residents in both control and trial areas to estimate the effectiveness of Olyset® Net at controlling the dengue vector, Aedes aegypti. Results The container-index and house-index for immature Ae. aegypti fell steeply one month after treatment in the trial area. Lids with Olyset® Net that fit container openings clearly seemed to reduce the presence of immature Ae. aegypti as the density of pupae decreased 1 month after treatment in the trial area. Pyriproxyfen was also effective at killing pupae in the water containers in the trial area. Although the dengue seroconversion rate was not influenced by Olyset® Net, it was lower in two-five year old

Field trial on a novel control method for the dengue vector, Aedes aegypti by the systematic use of Olyset® Net and pyriproxyfen in Southern Vietnam.

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

2013-01-11

Jars, tanks, and drums provide favorable rearing/breeding sites for Aedes aegypti in Vietnam. However, the use of insecticides to control mosquitoes at such breeding sites has not been approved in Vietnam since they are also often sources of drinking water, making larval vector control difficult. Mosquito nets pre-treated with long-lasting insecticide treated nets (LLITNs) form an effective measure for malaria control. We examined changes in the abundance of immature Aedes aegypti to evaluate the efficacy of covering ceramic jars with lids comprising one type of LLITN, Olyset® Net, in inhibiting oviposition by adult females, and to evaluate the effect of treating other breeding containers, such as flower vases, inside and around the outside of houses with a slow-release pyriproxyfen formulation to kill pupae. We selected 313 households for the trial and 363 households for the control in Tan Chanh, Long An province, Vietnam. In the trial area, Olyset® Net lids were used to cover five major types of water container (ceramic jars, cylindrical concrete tanks, other concrete tanks, plastic drums, and plastic buckets), while pyriproxyfen was used to treat flower vases and ant traps. We also monitored dengue virus transmission by measuring anti-dengue IgM and IgG levels in healthy residents in both control and trial areas to estimate the effectiveness of Olyset® Net at controlling the dengue vector, Aedes aegypti. The container-index and house-index for immature Ae. aegypti fell steeply one month after treatment in the trial area. Lids with Olyset® Net that fit container openings clearly seemed to reduce the presence of immature Ae. aegypti as the density of pupae decreased 1 month after treatment in the trial area. Pyriproxyfen was also effective at killing pupae in the water containers in the trial area. Although the dengue seroconversion rate was not influenced by Olyset® Net, it was lower in two-five year old children when compared to older children and adults in

Increasing Role of Roof Gutters as Aedes aegypti (Diptera: Culicidae Breeding Sites in Guadeloupe (French West Indies and Consequences on Dengue Transmission and Vector Control

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Joël Gustave

2012-01-01

Full Text Available During the past ten years, the islands of Guadeloupe (French West Indies are facing dengue epidemics with increasing numbers of cases and fatal occurrences. The vector Aedes aegypti is submitted to intensive control, with little effect on mosquito populations. The hypothesis that important Ae. aegypti breeding sites are not controlled is investigated herein. For that purpose, the roof gutters of 123 houses were systematically investigated, and the percentage of gutters positive for Ae. aegypti varied from 17.2% to 37.5%, from humid to dry locations. In the dryer location, most of houses had no other breeding sites. The results show that roof gutters are becoming the most important Ae. aegypti breeding sites in some locations in Guadeloupe, with consequences on dengue transmission and vector control.

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

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Thais Chouin-Carneiro

2016-03-01

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

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

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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. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Spatial pattern evolution of Aedes aegypti breeding sites in an Argentinean city without a dengue vector control programme

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Manuel O. Espinosa

2016-11-01

Full Text Available The main objective of this study was to obtain and analyse the space-time dynamics of Aedes aegypti breeding sites in Clorinda City, Formosa Province, Argentina coupled with landscape analysis using the maximum entropy approach in order to generate a dengue vector niche model. In urban areas, without vector control activities, 12 entomologic (larval samplings were performed during three years (October 2011 to October 2014. The entomologic surveillance area represented 16,511 houses. Predictive models for Aedes distribution were developed using vector breeding abundance data, density analysis, clustering and geoprocessing techniques coupled with Earth observation satellite data. The spatial analysis showed a vector spatial distribution pattern with clusters of high density in the central region of Clorinda with a well-defined high-risk area in the western part of the city. It also showed a differential temporal behaviour among different areas, which could have implications for risk models and control strategies at the urban scale. The niche model obtained for Ae. aegypti, based on only one year of field data, showed that 85.8% of the distribution of breeding sites is explained by the percentage of water supply (48.2%, urban distribution (33.2%, and the percentage of urban coverage (4.4%. The consequences for the development of control strategies are discussed with reference to the results obtained using distribution maps based on environmental variables.

Spatial pattern evolution of Aedes aegypti breeding sites in an Argentinean city without a dengue vector control programme.

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Espinosa, Manuel O; Polop, Francisco; Rotela, Camilo H; Abril, Marcelo; Scavuzzo, Carlos M

2016-11-21

The main objective of this study was to obtain and analyse the space-time dynamics of Aedes aegypti breeding sites in Clorinda City, Formosa Province, Argentina coupled with landscape analysis using the maximum entropy approach in order to generate a dengue vector niche model. In urban areas, without vector control activities, 12 entomologic (larval) samplings were performed during three years (October 2011 to October 2014). The entomologic surveillance area represented 16,511 houses. Predictive models for Aedes distribution were developed using vector breeding abundance data, density analysis, clustering and geoprocessing techniques coupled with Earth observation satellite data. The spatial analysis showed a vector spatial distribution pattern with clusters of high density in the central region of Clorinda with a well-defined high-risk area in the western part of the city. It also showed a differential temporal behaviour among different areas, which could have implications for risk models and control strategies at the urban scale. The niche model obtained for Ae. aegypti, based on only one year of field data, showed that 85.8% of the distribution of breeding sites is explained by the percentage of water supply (48.2%), urban distribution (33.2%), and the percentage of urban coverage (4.4%). The consequences for the development of control strategies are discussed with reference to the results obtained using distribution maps based on environmental variables.

Larvicidal Activity of essential oils from Brazilian plants against Aedes aegypti L.

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Eveline Solon Barreira Cavalcanti

2004-08-01

Full Text Available Aedes aegypti L. is the major vector of dengue fever, an endemic disease in Brazil. In an effort to find effective and affordable ways to control this mosquito, the larvicidal activities of essential oils from nine plants widely found in the Northeast of Brazil were analyzed by measurement of their LC50. The essential oils were extracted by steam distillation and their chemical composition determined by GL-chromatography coupled to mass spectroscopy. The essential oils from Cymbopogon citratus and Lippia sidoides, reported in the literature to have larvicidal properties against A. aegypti, were used for activity comparison. The results show that Ocimum americanum and Ocimum gratissimum have LC50 of 67 ppm and 60 ppm respectively, compared to 63 ppm for L. sidoides and 69 ppm for C. citratus. These results suggest a potential utilization of the essential oil of these two Ocimum species for the control of A. aegypti.

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

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Jéssica V. Nardeli

2012-06-01

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

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

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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.

Aedes aegypti, Aedes albopictus, and dengue in Argentina: current knowledge and future directions

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Darío Vezzani

2008-02-01

Full Text Available Since the reinfestation of South American countries by Ae. aegypti, dengue fever (DF and dengue hemorrhagic fever (DHF have become a major public health concern. The aim of this paper was to review the information related with Aedes vectors and dengue in Argentina since the reintroduction of Ae. aegypti in 1986. The geographic distribution of Ae. albopictus is restricted to the Northeast, and that of Ae. aegypti has expanded towards the South and the West in comparison with the records during the eradication campaign in the 1960s. Since 1998, 4,718 DF cases have been reported concentrated in the provinces of Salta, Formosa, Misiones, Jujuy and Corrientes. Despite the circulation of three dengue virus serotypes (DENV-1, -2 and -3 in the North of the country, DHF has not occurred until the present. The information published over the last two decades regarding mosquito abundance, temporal variations, habitat characteristics, competition, and chemical and biological control, was reviewed. Considering the available information, issues pending in Argentina are discussed. The presence of three DENV, the potential spread of Ae. albopictus, and the predicted climate change suggest that dengue situation will get worse in the region. Research efforts should be increased in the Northern provinces, where DHF is currently an actual risk.

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

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

2017-01-01

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

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

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

2017-07-01

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

VECTOR RESISTANCE STATUS OF DENGUE HEMORRHAGIC FEVER (Aedes aegypti IN THE SIDOREJO DISTRICT SALATIGA CITY AGAINST TEMEPHOS (ORGANOPHOSPHATES

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Ary Oktsari Yanti S

2014-06-01

Full Text Available One of the efforts to control the incidence of Dengue Hemorrhagic Fever (DHF is contrled thedengue vector larvae using larvasida. The most widely larvasida used to control larvae Ae.aegypti is temephos. In Indonesia 1% temephos (abate 1SG has been used since 1976, and since1980 has been used for the eradication program ofAe. aegypti larvae. The purpose of this studyis to determine the resistance status of vectors of dengue hemorrhagic fever (Ae. aegypti ofendemic, sporadic, and potentially in Sub District Sidorejo Salatiga City to temephos(organofosfat. This research was conducted using experimental research design (TrueExperiment, posttcst design with control groups (posttest-only Control Group Design. Thepopulation of the research were larvae of Ae. aegypti collected from the study area. Samples testlarvae were used of Ae. aegypti third and early fourth instars larvae which were maintenance ofthe first generation. The result showed that the mortality percentages of Ae. aegypti larvaeof endemic, sporadic and potential administratives against temephos using WHO standardconcentration (0,625; 0,125; 0,025 mg/1 indicates the mortality of Ae. aegypti larvae by 100%Based on the status resistance criteria, Ae. aegypti larvae from endemic, sporadic, and potentialadministratives of Sidorejo Sub-District, Salatiga City is still susceptible to temephos.Keywords : Status of resistance, Aedes aegypti. TemephosSalah satu upaya menurunkan Demam Berdarah Dengue (DBD adalah melaluipengcndalian jentik vektor DBD dengan larvasida. Larvasida yang digunakan untukmengcndalikan jentik Ae. aegypti adalah temephos. Temephos 1% (abate ISG sudah programdi Indonesia sejak 1976, scjak 1980 telah digunakan secara massal untuk programpemberantasan jentik Ae. aegypti. Tujuan penelitian ini adalah untuk mengetahui status resistensivektor demam berdarah dengue Ae. aegypti di kclurahan endemis, sporadis, dan potensialKecamatan Sidorejo Kota Salatiga terhadap temephos

Aktivitas enzim monooksigenase pada populasi nyamuk Aedes aegypti di Kecamatan Tembalang, Kota Semarang

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Dyah Widiastuti

2015-06-01

Full Text Available Abstract. 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 Keywords: monooxygenase, insecticide, Ae. aegypti, resistance  Abstrak. Demam Berdarah Dengue (DBD masih menjadi masalah kesehatan utama di Kecamatan Tembalang, Kota Semarang. Tindakan fogging untuk pengendalian vektor DBD sering dilakukan. Penggunaan insektisida dari golongan yang sama dalam waktu cukup lama dapat memicu terjadinya resistensi. Tujuan penelitian untuk mengamati aktivitas enzim monooksigenase pada populasi nyamuk Aedes aegypti di Kecamatan Tembalang, Kota Semarang. Penelitian dilaksanakan bulan Februari-November 2014 dengan desain potong lintang di 10 desa di Kecamatan Tembalang, Kota Semarang. Pada penelitian ini dilakukan pemasangan ovitrap untuk mendapatkan sampel telur yang dipelihara menjadi nyamuk dewasa. Sampel homogenate nyamuk disimpan pada suhu -85°C, selanjutnya dilakukan peng-ujian resistensi dengan uji biokimia untuk melihat aktivitas enzim

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

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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

Pengaruh Frekuensi Penghisapan Darah Terhadap Perkembangan, Reproduksi,vertilitas Dan Rasio Sex Aedes Aegypti

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Setiyaningsih, Riyani; Agustini, Maria

2012-01-01

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 cupsindi...

Expansión del Aedes aegypti a localidades rurales de Cajamarca

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Lucinda Troyes R

2006-07-01

Full Text Available Objetivos: Determinar la presencia, magnitud y expansión de Aedes aegypti en las localidades rurales de las provincias de Jaén y San Ignacio, departamento de Cajamarca. Materiales y métodos: Estudio transversal realizado entre abril y mayo de 2004, en 21 (100% localidades rurales ubicadas en las márgenes de la carretera Jaén-San Ignacio y al interior de ella, hasta en 90 minutos. Se inspeccionó recipientes de 1460 viviendas para la búsqueda de larvas y adultos del mosquito, se determinaron los índices aédicos, de recipiente y de Breteau. Resultados: Se demostró la presencia de Aedes aegypti en tres localidades rurales de la provincia de Jaén y en cuatro de la provincia de San Ignacio. Los índices aédicos variaron de 1,2 a 16,6%. Los recipientes infestados con mayor frecuencia fueron las llantas y los artículos en desuso. Conclusiones: Se reporta la expansión de A. aegypti en la tercera parte de localidades rurales de las provincias de Jaén y San Ignacio; esta expansión necesita ser más estudiada y considerada al implementarse las estrategias de prevención y control del dengue en la DISA Jaén, para evitar la aparición de brotes de dengue clásico, dengue hemorrágico, incluso fiebre amarilla urbana.

Coexistence of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in Peninsular Florida Two Decades After Competitive Displacements.

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Lounibos, L Philip; Bargielowski, Irka; Carrasquilla, María Cristina; Nishimura, Naoya

2016-11-01

The spread of Aedes albopictus (Skuse) eastward in the mid-1980s from its initial establishment in Houston, TX, was associated with rapid declines and local disappearances of Aedes aegypti (L.) in Gulf Coast states and Florida where annual larval surveillance during the early 1990s described temporal and spatial patterns of competitive displacements in cemeteries and tire shops. Approximately 20 yr later in 2013-2014, we re-visited former collection sites and sampled aquatic immatures of these two species from tire shops in 10 cities on State Route 441 and from 9 cemeteries from Lakeland to Miami in southwest Florida. In the recent samples Ae. aegypti was recovered from three central Florida cities where it had not been detected in 1994, but its northern limit on Rte. 441, Apopka, did not change. Other evidence, such as trends at a few cemeteries, suggested a moderate resurgence of this species since 1994. Cage experiments that exposed female progeny of Ae. aegypti from recent Florida collection sites to interspecific mating by Ae. albopictus males showed that females from coexistence sites had evolved resistance to cross-mating, but Ae. aegypti from sites with no Ae. albopictus were relatively susceptible to satyrization. Habitat classifications of collection sites were reduced by principal component (PC) analysis to four variables that accounted for > 99% of variances; PCs with strong positive loadings for tree cover and ground vegetation were associated with collection sites yielding only Ae. albopictus Within the coexistence range of the two species, the numbers of Ae. aegypti among total Aedes collected were strongly correlated in stepwise logistic regression models with two habitat-derived PCs, distance from the coast, and annual rainfall and mean maximum temperatures at the nearest weather station. Subtle increases in the range of Ae. aegypti since its previous displacements are interpreted in the context of the evolution of resistance to mating

Enkapsulasi B. bassiana menggunakan maizena dan daya infeksinya terhadap larva Aedes aegypti, Anopheles sp., Culex sp.

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Mutiara Widawati

2015-12-01

Full Text Available Abstract. Encapsulation formulae of mycoinsecticide have to be able to maintain fungus viability and pathogenicity. This mycoinsecticide was developed as an alternative way to control mosquito borne disease. The aim of this study was to encapsulate Beauveria bassiana as viable storage and have the capability to kill larvae of Aedes aegypti, Anopheles sp. and Culex sp. Mosquito larvae obtained from laboratory reared at health research laboratory; Loka Litbang P2B2 Ciamis. The treatments made in this study were the formu-lation of cornstarch and controls for comparison. This study showed potential formulation of cornstarch encapsulation as a biolarvacidal. Cornstarch formulations proven to be succeed in maintaining fungus viability, however, the pathogenicity of the microcapsule still not effective to kill Aedes, Culex and Anopheles larvae. Keywords: encapsulation, Beauveria bassiana, Ae.aegypti, Anopheles sp., Culex sp. Abstrak. Pembuatan formula bioinsektisida yang optimal sebagai salah satu alternatif untuk pengen-dalian nyamuk vektor perlu di kembangkan. Sediaan mikoinsektisida yang dibuat harus dapat memper-tahankan viabilitas jamur B. bassiana sehingga masih efektif pada saat penggunaannya. Salah satu cara yang digunakan untuk menjaga kestabilan sediaan mikoinsektisida yang berdampak langsung pada via-bilitas jamur adalah dengan menerapkan metode enkapsulasi. Penelitian ini bertujuan untuk meng-hasilkan sediaan mikokapsul dari Beauvaria bassiana melalui proses enkapsulasi menggunakan maizena yang memiliki kapabilitas tinggi sebagai penyimpan B. bassiana dan efektif dalam membunuh larva dan telur Aedes aegypti, Anopheles sp. dan Culex sp. Semua larva uji berasal dari insektarium laboratorium penelitian kesehatan Loka litbang P2B2 Ciamis. Pembuatan enkapsulasi dimulai dengan kultur dan pema-nenan B. bassiana, uji viabilitas, proses enkapsulasi serta uji larvasida di laboratorium. Uji dilakukan dengan satu perlakuan dan satu kontrol untuk

A Sequence of Flushing and Drying of Breeding Habitats of Aedes aegypti (L. Prior to the Low Dengue Season in Singapore.

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Osama M E Seidahmed

2016-07-01

Full Text Available In dengue-endemic areas, transmission shows both a seasonal and interannual variability. To investigate how rainfall impacts dengue seasonality in Singapore, we carried out a longitudinal survey in the Geylang neighborhood from August 2014 to August 2015. The survey comprised of twice-weekly random inspections to outdoor breeding habitats and continuous monitoring for positive ones. In addition, observations of rainstorms were collected. Out of 6824 inspected habitats, 67 contained Aedes aegypti, 11 contained Aedes albopictus and 24 contained Culex spp. The main outdoors habitat of Aedes aegypti was storm drains (54/67. We found that 80% of breeding sites in drains (43/54 were lost after intense rainstorms related to the wet phase of the Northeast monsoon (NE between November 2014 and early January 2015. Subsequently, 95% (41/43 of these flushed drains had dried out during the dry phase of the NE in late January-February 2015. A return in the outdoor breeding of Aedes aegypti was observed after the onset of Southwest monsoon (SW between May and August 2015. There was also a reduction in productivity of breeding habitats for larvae and pupae after the onset of the NE. In wet equatorial regions like Singapore, rainfall varies with the monsoons. A monsoon-driven sequence of flushing and drying shapes the outdoor seasonal abundance of Aedes aegypti. This finding can be used to optimize vector control strategies and better understand dengue in the context of climate change.

A Sequence of Flushing and Drying of Breeding Habitats of Aedes aegypti (L.) Prior to the Low Dengue Season in Singapore.

Science.gov (United States)

Seidahmed, Osama M E; Eltahir, Elfatih A B

2016-07-01

In dengue-endemic areas, transmission shows both a seasonal and interannual variability. To investigate how rainfall impacts dengue seasonality in Singapore, we carried out a longitudinal survey in the Geylang neighborhood from August 2014 to August 2015. The survey comprised of twice-weekly random inspections to outdoor breeding habitats and continuous monitoring for positive ones. In addition, observations of rainstorms were collected. Out of 6824 inspected habitats, 67 contained Aedes aegypti, 11 contained Aedes albopictus and 24 contained Culex spp. The main outdoors habitat of Aedes aegypti was storm drains (54/67). We found that 80% of breeding sites in drains (43/54) were lost after intense rainstorms related to the wet phase of the Northeast monsoon (NE) between November 2014 and early January 2015. Subsequently, 95% (41/43) of these flushed drains had dried out during the dry phase of the NE in late January-February 2015. A return in the outdoor breeding of Aedes aegypti was observed after the onset of Southwest monsoon (SW) between May and August 2015. There was also a reduction in productivity of breeding habitats for larvae and pupae after the onset of the NE. In wet equatorial regions like Singapore, rainfall varies with the monsoons. A monsoon-driven sequence of flushing and drying shapes the outdoor seasonal abundance of Aedes aegypti. This finding can be used to optimize vector control strategies and better understand dengue in the context of climate change.

AVALIAÇÃO DA VIRULENCIA DE BLASTOSPOROS DE Metarhizium anisopliae NO CONTROLE DE LARVAS DE CAMPO DO MOSQUITO Aedes aegypti

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Aline Teixeira Carolino

2016-11-01

Full Text Available Atualmente no Brasil, o mosquito Aedes aegypti é transmissor das arboviroses dengue, chikungunya e Zika. Não existe tratamento específico para estas doenças. A redução da população do vetor ainda é o método mais eficaz para reduzir a taxa dessas arboviroses. O presente estudo comparou a virulência de conídios e blastosporos de Metarhizium anisopliae contra larvas do mosquito A. aegypti provenientes de coletas no campo. Blastosporos foram mais virulentos para larvas, sendo observada mortalidade total das larvas em apenas 48 horas. Larvas infectadas com conídios apresentaram 100% de mortalidade no quinto dia pós-infecção. O presente estudo mostra que blastosporos apresentam grande potencial para controle de larvas de A. aegypti no campo.

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

KAUST Repository

Lee, S. Seirin; Baker, Ruth E.; Gaffney, Eamonn A.; White, Steven M.

2013-01-01

(Release of Insects carrying a Dominant Lethal), for controlling invasion of the mosquito Aedes aegypti using a spatial stage-structured mathematical model. In particular, we explore the use of a barrier zone of sterile/transgenic insects to prevent

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

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Michael Russelle Alvarez

2016-02-01

Full Text Available 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.

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

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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

Determinants of Heterogeneous Blood Feeding Patterns by Aedes aegypti in Iquitos, Peru

OpenAIRE

Liebman, Kelly A.; Stoddard, Steven T.; Reiner, Robert C.; Perkins, T. Alex; Astete, Helvio; Sihuincha, Moises; Halsey, Eric S.; Kochel, Tadeusz J.; Morrison, Amy C.; Scott, Thomas W.

2014-01-01

Background Heterogeneous mosquito biting results in different individuals in a population receiving an uneven number of bites. This is a feature of many vector-borne disease systems that, if understood, could guide preventative control efforts toward individuals who are expected to contribute most to pathogen transmission. We aimed to characterize factors determining biting patterns of Aedes aegypti, the principal mosquito vector of dengue virus. Methodology/Principal Findings Engorged female...

Determination of Insecticidal Effect (LC50 and LC90) of Organic Fatty Acids Mixture (C8910+Silicone) Against Aedes aegypti and Aedes albopictus (Diptera: Culicidae).

Science.gov (United States)

Dunford, James C; Falconer, Aneika; Leite, Laura N; Wirtz, Robert A; Brogdon, William G

2016-05-01

Emerging and re-emerging vector-borne diseases such as chikungunya and dengue and associated Aedes vectors are expanding their historical ranges; thus, there is a need for the development of novel insecticides for use in vector control programs. The mosquito toxicity of a novel insecticide and repellent consisting of medium-chain carbon fatty acids (C8910) was examined. Determination of LC 50 and LC 90 was made against colony-reared Aedes aegypti (L.) and Aedes albopictus (Skuse) using probit analysis on mortality data generated by Centers for Disease Control and Prevention bottle bioassays. Six different concentrations of C8910 + silicone oil yielded an LC 50 of 160.3 µg a.i/bottle (147.6-182.7) and LC 90 of 282.8 (233.2-394.2) in Ae. aegypti; five concentrations yielded an LC 50 of 125.4 (116.1-137.6) and LC 90 of 192.5 (165.0-278.9) in Ae. albopictus. Further development of C8910 and similar compounds could provide vector control specialists novel insecticides for controlling insect disease vectors. Published by Oxford University Press on behalf of Entomological Society of America 2015. This work is written by US Government employees and is in the public domain in the US.

Oviposition Site Selection by the Dengue Vector Aedes aegypti and Its Implications for Dengue Control

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Wong, Jacklyn; Stoddard, Steven T.; Astete, Helvio; Morrison, Amy C.; Scott, Thomas W.

2011-01-01

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

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

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Duangkamon Sritabutra

2013-08-01

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

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

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Arjunan Nareshkumar

2012-12-01

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

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

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Luciano Pamplona de Góes Cavalcanti

2007-08-01

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

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

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Honorio, Nildimar A.

2007-01-01

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)

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

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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)

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...

Field and semi-field evaluation of Bacillus thuringiensis var. israelensis versus Temephos® in Aedes aegypti controlAvaliação de campo e simulado de campo de Bacillus thuringiensis var. israelensis versus Temephos® no controle de Aedes aegypti

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Jose Bento Pereira Lima

2016-06-01

Full Text Available Introduction: Aedes aegypti  is a vector of the important arboviruses worldwide. Vector control continues to rely mainly on fighting immature stages. Resistance to the larvicide Temephos® was detected in many regions of Brazil since 2000 what led control programs to search for alternative products, such as Bacillus thuringiensis var. israelensis (Bti. Caicó municipality (Rio Grande do Norte State, Brazil was one of the first cities to use Bti. However, after some time, Bti low persistence was noticed as jeopardizing effective vector control. Objective: To compare the efficacy of two Bti granulate formulations, Vectobac G® and Vectobac WDG® and Temephos® against Ae. aegypti in field and semi-field conditions. Methods: Field tests were carried out in two neighbouring  areas which presented Ae. aegypti infestation indices >3%: Walfredo Gurgel and Boa Passagem, Caicó, RGN, Brazil, in 2004. Semi- field tests were performed in the patio of a building. Results: For the field conditions, mortality rates >80% were maintained for 14 days, average. After nine weeks, positive containers for Ae. aegypti in the field were >10% in the area of application of Bti and <1% in the area where Temephos® was applied. In the semi-field conditions Ae. aegypti larval mortality >80% was maintained for up to 56 days for Temephos®, 35 days for Vectobac G® and 49 days for Vectobac WDG®. Conclusions: The results point out to low Bti persistence in the field, mainly for containers exposed to sunlight. Local climatic and environmental conditions should be regarded when new products are tested due to high regional variability prevailing in Brazil. 

Impact of Diurnal Temperature Fluctuations during Larval Development on Adult Life History Traits and Insecticide Susceptibility in Two Vectors; Anopheles gambiae and Aedes aegypti

Science.gov (United States)

2014-04-30

ANOPHELES GAMBIAE AND AEDES AEGYPTI. by Jeffrey W. Clark Dissertation submitted to the Faculty of the Department of Preventive Medicine and...Vectors; Anopheles gambiae and Aedes aegypti." Name of Candidate: Jeffrey Clark Doctor of Philosophy Degree April 30, 2014 DISSERTATION AND ABSTRACT...for the many fruitful discussions and the standing offer to help whenever I needed it; and to Joe Wagman, for providing needed Aedes aegypti eggs from

The endosymbiotic bacterium Wolbachia induces resistance to dengue virus in Aedes aegypti.

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Guowu Bian

2010-04-01

Full Text Available Genetic strategies that reduce or block pathogen transmission by mosquitoes have been proposed as a means of augmenting current control measures to reduce the growing burden of vector-borne diseases. The endosymbiotic bacterium Wolbachia has long been promoted as a potential vehicle for introducing disease-resistance genes into mosquitoes, thereby making them refractory to the human pathogens they transmit. Given the large overlap in tissue distribution and intracellular localization between Wolbachia and dengue virus in mosquitoes, we conducted experiments to characterize their interactions. Our results show that Wolbachia inhibits viral replication and dissemination in the main dengue vector, Aedes aegypti. Moreover, the virus transmission potential of Wolbachia-infected Ae. aegypti was significantly diminished when compared to wild-type mosquitoes that did not harbor Wolbachia. At 14 days post-infection, Wolbachia completely blocked dengue transmission in at least 37.5% of Ae. aegypti mosquitoes. We also observed that this Wolbachia-mediated viral interference was associated with an elevated basal immunity and increased longevity in the mosquitoes. These results underscore the potential usefulness of Wolbachia-based control strategies for population replacement.

Identification and characterisation of Aedes aegypti aldehyde dehydrogenases involved in pyrethroid metabolism.

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Nongkran Lumjuan

Full Text Available Pyrethroid insecticides, especially permethrin and deltamethrin, have been used extensively worldwide for mosquito control. However, insecticide resistance can spread through a population very rapidly under strong selection pressure from insecticide use. The upregulation of aldehyde dehydrogenase (ALDH has been reported upon pyrethroid treatment. In Aedes aegypti, the increase in ALDH activity against the hydrolytic product of pyrethroid has been observed in DDT/permethrin-resistant strains. The objective of this study was to identify the role of individual ALDHs involved in pyrethroid metabolism.Three ALDHs were identified; two of these, ALDH9948 and ALDH14080, were upregulated in terms of both mRNA and protein levels in a DDT/pyrethroid-resistant strain of Ae. aegypti. Recombinant ALDH9948 and ALDH14080 exhibited oxidase activities to catalyse the oxidation of a permethrin intermediate, phenoxybenzyl aldehyde (PBald, to phenoxybenzoic acid (PBacid.ALDHs have been identified in association with permethrin resistance in Ae. aegypti. Characterisation of recombinant ALDHs confirmed the role of this protein in pyrethroid metabolism. Understanding the biochemical and molecular mechanisms of pyrethroid resistance provides information for improving vector control strategies.

Family level variation in Wolbachia-mediated dengue virus blocking in Aedes aegypti

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Terradas, Gerard; Allen, Scott L.; Chenoweth, Stephen F.; McGraw, Elizabeth A.

2017-01-01

Background The mosquito vector Aedes aegypti is responsible for transmitting a range of arboviruses including dengue (DENV) and Zika (ZIKV). The global reach of these viruses is increasing due to an expansion of the mosquito’s geographic range and increasing urbanization and human travel. Vector control remains the primary means for limiting these diseases. Wolbachia pipientis is an endosymbiotic bacterium of insects that has the ability to block the replication of pathogens, including flaviv...

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

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David W. Severson

2016-10-01

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

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.

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Hiscox, Alexandra; Kaye, Angela; Vongphayloth, Khamsing; Banks, Ian; Piffer, Michele; Khammanithong, Phasouk; Sananikhom, Pany; Kaul, Surinder; Hill, Nigel; Lindsay, Steven W; Brey, Paul T

2013-06-01

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 most common in water storage jars (odds ratio [OR] = 4.72) and tires (OR = 2.99), and Ae. albopictus pupae were associated with tires in 2009 (OR = 10.87) and drums, tires, and jars in 2010 (drums OR = 3.05; tires OR = 3.45, jars OR = 6.59). Compared with water storage vessels, containers used for hygiene, cooking, and drinking were 80% less likely to harbor Ae. albopictus pupae in 2010 (OR = 0.20), and discarded waste was associated with a 3.64 increased odds of infestation. Vector control efforts should focus on source reduction of water storage containers, particularly concrete jars and tires.

Perturbed cholesterol and vesicular trafficking associated with dengue blocking in Wolbachia-infected Aedes aegypti cells.

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Geoghegan, Vincent; Stainton, Kirsty; Rainey, Stephanie M; Ant, Thomas H; Dowle, Adam A; Larson, Tony; Hester, Svenja; Charles, Philip D; Thomas, Benjamin; Sinkins, Steven P

2017-09-13

Wolbachia are intracellular maternally inherited bacteria that can spread through insect populations and block virus transmission by mosquitoes, providing an important approach to dengue control. To better understand the mechanisms of virus inhibition, we here perform proteomic quantification of the effects of Wolbachia in Aedes aegypti mosquito cells and midgut. Perturbations are observed in vesicular trafficking, lipid metabolism and in the endoplasmic reticulum that could impact viral entry and replication. Wolbachia-infected cells display a differential cholesterol profile, including elevated levels of esterified cholesterol, that is consistent with perturbed intracellular cholesterol trafficking. Cyclodextrins have been shown to reverse lipid accumulation defects in cells with disrupted cholesterol homeostasis. Treatment of Wolbachia-infected Ae. aegypti cells with 2-hydroxypropyl-β-cyclodextrin restores dengue replication in Wolbachia-carrying cells, suggesting dengue is inhibited in Wolbachia-infected cells by localised cholesterol accumulation. These results demonstrate parallels between the cellular Wolbachia viral inhibition phenotype and lipid storage genetic disorders. Wolbachia infection of mosquitoes can block dengue virus infection and is tested in field trials, but the mechanism of action is unclear. Using proteomics, Geoghegan et al. here identify effects of Wolbachia on cholesterol homeostasis and dengue virus replication in Aedes aegypti.

Widespread evidence for interspecific mating between Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in nature.

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Bargielowski, I E; Lounibos, L P; Shin, D; Smartt, C T; Carrasquilla, M C; Henry, A; Navarro, J C; Paupy, C; Dennett, J A

2015-12-01

Aedes aegypti and Aedes albopictus, two important vectors of the dengue and chikungunya viruses to humans, often come in contact in their invasive ranges. In these circumstances, a number of factors are thought to influence their population dynamics, including resource competition among the larval stages, prevailing environmental conditions and reproductive interference in the form of satyrization. As the distribution and abundance of Ae. aegypti and Ae. albopictus have profound epidemiological implications, understanding the competitive interactions that influence these patterns in nature is important. While evidence for resource competition and environmental factors had been gathered from the field, the evidence for reproductive interference, though strongly inferred through laboratory trials, remained sparse (one small-scale field trial). In this paper we demonstrate that low rates (1.12-3.73%) of interspecific mating occur in nature among populations of these species that have co-existed sympatrically from 3 to 150yrs. Finally this report contributes a new species-specific primer set for identifying the paternity of sperm extracted from field collected specimens. Copyright © 2015 Elsevier B.V. All rights reserved.

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

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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. © 2015 The Society for Vector Ecology.

Effects of Aedes aegypti salivary components on dendritic cell and lymphocyte biology

Czech Academy of Sciences Publication Activity Database

Bizzarro, B.; Barros, M.S.; Maciel, C.; Gueroni, D.I.; Lino, C.N.; Campopiano, J.; Kotsyfakis, Michalis; Amarante-Mendes, G.P.; Calvo, E.; Capurro, M.L.; Sa-Nunes, A.

2013-01-01

Roč. 6, NOV 2013 (2013), s. 329 ISSN 1756-3305 Institutional support: RVO:60077344 Keywords : dendritic cells * T-cells * Aedes aegypti * saliva * apoptosis Subject RIV: EC - Immunology Impact factor: 3.251, year: 2013

Determinasi Strain Aedes aegypti (Linn. yang Rentan Homozigot dengan Metode Seleksi Indukan Tunggal

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Isfanda Isfanda

2017-06-01

Full Text Available Abstract. Aedes aegypti is a type of mosquito that can carry dengue virus, yellow fever and chikunguya. The spread of this mosquito is very broad, covering almost all tropical regions worldwide. This study aims to determine the vulnerability status of homozygous Ae. aegypti. Sample of Ae. aegypti is mosquito strain from Health Entomology Laboratory Bogor Institute of Agriculture and at random sampling. Ae. aegypti eggs which comes from the breeders hatched separately. Insecticide‐treated paper (impregnated paper malathion, bendiokarb and deltamethrin are use for insecticides testing using WHO test kit. The analysis showed that the mosquito Ae. aegypti tested with a single sib‐selection method and were exposed to the insecticide malathion, propoksur, and showed an increasing trend sipermetrin vulnerability homozygous at each generation. As for the fourth generation (F4 has not shown changes into a strain that is homozygous susceptible to three types of insecticides. The formation of homozygous susceptible strains take over five generations.Keywords: Ae. aegypti, malathion, bendiocarb, deltamethrin, single sib‐selection methodAbstrak. Aedes aegypti merupakan jenis nyamuk yang dapat membawa virus dengue, demam kuning (yellow fever dan chikunguya. Penyebaran nyamuk ini sangat luas, meliputi hampir semua daerah tropis di seluruh dunia. Penelitian ini bertujuan mengetahui status kerentanan nyamuk Ae. aegypti secara homozigot. Nyamuk Ae. aegypti yang dijadikan sampel yaitu nyamuk dewasa strain yang ada di Laboratorium Entomologi Kesehatan Institut Pertanian Bogor dan diambil secara acak. Telur Ae. aegypti yang berasal dari satu indukan ditetaskan secara terpisah. Insektisida yang digunakan untuk pengujian menggunakan kertas berinsektisida (impregnated paper malation, bendiokarb, dan deltametrin dengan menggunakan WHO test kit. Hasil analisis menunjukkan bahwa nyamuk Ae. aegypti yang diuji dengan metode seleksi indukan tunggal serta dipaparkan

Effect of an intervention in storm drains to prevent Aedes aegypti reproduction in Salvador, Brazil.

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Souza, Raquel Lima; Mugabe, Vánio André; Paploski, Igor Adolfo Dexheimer; Rodrigues, Moreno S; Moreira, Patrícia Sousa Dos Santos; Nascimento, Leile Camila Jacob; Roundy, Christopher Michael; Weaver, Scott C; Reis, Mitermayer Galvão; Kitron, Uriel; Ribeiro, Guilherme Sousa

2017-07-11

Aedes aegypti, the principal vector for dengue, chikungunya and Zika viruses, is a synanthropic species that uses stagnant water to complete its reproductive cycle. In urban settings, rainfall water draining structures, such as storm drains, may retain water and serve as a larval development site for Aedes spp. reproduction. Herein, we describe the effect of a community-based intervention on preventing standing water accumulation in storm drains and their consequent infestation by adult and immature Ae. aegypti and other mosquitoes. Between April and May of 2016, local residents association of Salvador, Brazil, after being informed of water accumulation and Ae. aegypti infestation in the storm drains in their area, performed an intervention on 52 storm drains. The intervention consisted of placing concrete at the bottom of the storm drains to elevate their base to the level of the outflow tube, avoiding water accumulation, and placement of a metal mesh covering the outflow tube to avoid its clogging with debris. To determine the impact of the intervention, we compared the frequency at which the 52 storm drains contained water, as well as adult and immature mosquitoes using data from two surveys performed before and two surveys performed after the intervention. During the pre-intervention period, water accumulated in 48 (92.3%) of the storm drains, and immature Ae. aegypti were found in 11 (21.2%) and adults in 10 (19.2%). After the intervention, water accumulated in 5 (9.6%) of the storm drains (P Aedes mosquitoes (mainly Culex spp.) in the storm drains also decreased after the intervention. This study exemplifies how a simple intervention targeting storm drains can result in a major reduction of water retention, and, consequently, impact Ae. aegypti larval populations. Larger and multi-center evaluations are needed to confirm the potential of citywide structural modifications of storm drains to reduce Aedes spp. infestation level.

Plan Continental de ampliación e intensificación del combate a Aedes aegypti

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1998-01-01

Full Text Available Campaigns for the eradication of Aedes aegypti, the mosquito vector responsible for spreading dengue and yellow fever, enjoyed great success during the forties and fifties. Between 1948 and 1962, A. aegypti disappeared from 21 countries in the Region of the Americas, but lack of sustainability of the programs resulted in the gradual reinfestation of practically all countries. In an effort to combat the situation, in 1995 PAHO began to help its Member States with the creation of an expert panel charged with drawing up a continental plan of action for eradicating A. aegypti from all countries. The Continental Plan for expanding and intensifying the war against Aedes aegypti was drawn up in Caracas, Venezuela, in April of 1997, in accordance with the objectives previously established by the countries. The plan's success will depend on having all countries commit themselves to putting it into effect and to providing the national funds that are needed for its full implementation.

Raw sewage as breeding site to Aedes (Stegomyia) aegypti (Diptera, culicidae).

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Chitolina, R F; Anjos, F A; Lima, T S; Castro, E A; Costa-Ribeiro, M C V

2016-12-01

The selection of oviposition sites by females of Aedes (Stegomyia) aegypti is a key factor for the larval survival and egg dispersion and has a direct influence in vector control programs. In this study, we evaluated the aspects of reproductive physiology of Ae. aegypti mosquitoes tested in the presence of raw sewage. Ae. aegypti females were used in oviposition bioassays according to two methodologies: (i) choice assay, in which three oviposition substrates were offered in the same cage: treatment (raw sewage), positive control (distilled water) and negative control (1% sodium hypochlorite) and; (ii) no choice assay, in which only one substrate was available. The physicochemical and microbiological analysis of the raw sewage used in this study indicated virtually no levels of chlorine, low levels of dissolved oxygen and high levels of nitrogenous compounds as well as the presence of Escherichia coli and total fecal coliforms. After 72h of oviposition, the eggs were counted and there was no statistically significant difference (p>0.05) in the oviposition rate between raw sewage and positive control in both methodologies. In addition, females were dissected to evaluate egg-retention and also there were no appreciable differences in egg retention even when raw sewage was the only substrate offered. The data also showed that egg hatching and larvae development occurred normally in the raw sewage. Therefore, the present study suggests that Ae. aegypti can adapt to new sites and lay eggs in polluted water, such as the raw sewage. These findings are of particular importance for the control and surveillance programs against Ae. aegypti in countries where the conditions of poor infrastructure and lack of basic sanitation are still an issue. Copyright © 2016 Elsevier B.V. All rights reserved.

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

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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.

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

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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.

History of domestication and spread of Aedes aegypti - A Review

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Jeffrey R Powell

2013-01-01

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

Effects of insemination and blood-feeding on locomotor activity of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) females under laboratory conditions

OpenAIRE

Lima-Camara, Tamara N; Lima, José B P; Bruno, Rafaela V; Peixoto, Alexandre A

2014-01-01

Abstract Background Dengue is an arbovirus disease transmitted by two Aedes mosquitoes: Ae. aegypti and Ae. albopictus. Virgin females of these two species generally show a bimodal and diurnal pattern of activity, with early morning and late afternoon peaks. Although some studies on the flight activity of virgin, inseminated and blood-fed Ae. aegypti females have been carried out under laboratory conditions, little...

Aedes aegypti D7 Saliva Protein Inhibits Dengue Virus Infection.

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Michael J Conway

2016-09-01

Full Text Available 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.

Indeks Pertumbuhan Larva Aedes aegypti L. Yang Terdedah Dalam Ekstrak Air Kulit Jengkol (Pithecellobium lobatum

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Firda Yanuar Pradani

2013-02-01

Full Text Available Abstracts. The control of dengue fever (DBD vector generally use the synthetic insecti­cides, however it's utilization had negative effect to the environment. Jengkol (Pithecellobium lobaturn was one of the plants which could be used as larvacide alternative because it had phenolate acid, alkaloid, terpenoid and saponin in its rind. This research was conducted to know the growth index of Aedes aegypti larvae which was soaked in the extract ofP. lobaturn rind. This experiment used P. lobaturn rind ekstract at concentration 36%, 18%, 9% and 0% . The data were analyzed by using Zhang et.al methode (1993. The P. lobaturn rind extract were toxic to larvae especially in first and second instar at concentration 17,94% respectively. Relativelly growth index range from 0,817-1, it is mean that some larvae were stuned, and some were growth into the next phase.Key words: Aedes aegypti, Jengkol, LCso, growth index.

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

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Wanessa Porto Tito Gambarra

2013-04-01

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

Daya Repelan dan Uji Iritasi Formula Lotion Ekstrak Etanol Daun Sirih (Piper Betle Linn) dengan Variasi Basis Lanolin terhadap Nyamuk Aedes Aegypti

OpenAIRE

Fitriana, Apri Yudis; Wahyuningrum, Retno; Sudarso, Sudarso

2012-01-01

Demam berdarah dengue (DBD) yang ditularkan melalui gigitan nyamuk Aedes aegypti dan Aedes albopictus betina masih menjadi masalah kesehatan khususnya di Indonesia. Sediaan repelan biasa digunakan untuk menghindari gangguan atau gigitan nyamuk Aedes aegypti. Namun sediaan repelan mengandung Diethyl toluamide (DEET) yang dalam penggunaannya dapat menyebabkan eritema (kemerahan pada kulit) dan iritasi. Penelitian ini bertujuan untuk menentukan aktivitas daya repelan lotion ekstrak daun sirih de...

Composition of the Essential Oil of Pink Chablis Bluebeard (Caryopteris x clandonensis ’Durio’) and Its Biological Activity against the Yellow Fever Mosquito Aedes aegypti

Science.gov (United States)

2016-04-07

oil of Pink Chablis™ bluebeard (Caryopteris ×clandonensis ’Durio’) and its biological activity against the yellow fever mosquito Aedes aegypti ARTICLE...bluebeard (Caryopteris ×clandonensis ’Durio’) and its biological activity against the yellow fever mosquito Aedes aegypti Eugene K. Blythe1...mosquito [ Aedes aegypti (L.) (Diptera: Culicidae)]. Essential oil from the aerial parts of this mildly aromatic ornamental species was extracted by water

Effect of Aedes aegypti exposure to spatial repellent chemicals on BG-Sentinel™ trap catches.

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Salazar, Ferdinand V; Achee, Nicole L; Grieco, John P; Prabaripai, Atchariya; Ojo, Tolulope A; Eisen, Lars; Dureza, Christine; Polsomboon, Suppaluck; Chareonviriyaphap, Theeraphap

2013-05-20

An integrated approach to reduce densities of adult Aedes aegypti inside homes is currently being evaluated under experimentally controlled field conditions. The strategy combines a spatial repellent (SR) treatment (applied indoors) with the Biogents Sentinel™ (BGS) mosquito trap positioned in the outdoor environment. In essence, when combined, the goal is to create a push-pull mechanism that will reduce the probability of human-vector contact. The current study measured BGS recapture rates of Ae. aegypti test cohorts that were exposed to either SR or control (chemical-free) treatments within experimental huts. The objective was to define what, if any, negative impact SR may have on BGS trap efficacy (i.e., reduced BGS collection). Aedes aegypti females were exposed to SR compounds within experimental huts in the form of either treated fabric (DDT and transfluthrin) or mosquito coil (metofluthrin). Test cohorts were released within individual screen house cubicles, each containing 4 BGS traps, following SR exposure according to treatment. Two separate test cohorts were evaluated: (i) immediate release (IR) exposed from 06:00-12:00 hours and released at 12:00 hours and (ii) delayed release (DR) exposed from12:00-18:00 hours and released at 05:30 hours the following day. BGS recapture was monitored at 09:30, 13:30 and 15:30 hours and the cumulative recapture by time point quantified. Exposure of Ae. aegypti females to either DDT or metofluthrin did not significantly impact BGS capture as compared to cohorts of non-exposed females. This was true for both IR and DR exposure populations. IR cohorts exposed to transfluthrin resulted in significantly lower BGS recapture compared to matched controls but this effect was primarily due to high mosquito mortality during transfluthrin trials. Our data indicate no more than minor and short-lived impacts (i.e., reduced attraction) on BGS trap catches following exposure to the pyrethroid compounds transfluthrin and metofluthrin

Oral infection of Aedes aegypti with yellow fever virus: geographic variation and genetic considerations.

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Tabachnick, W J; Wallis, G P; Aitken, T H; Miller, B R; Amato, G D; Lorenz, L; Powell, J R; Beaty, B J

1985-11-01

Twenty-eight populations representing a worldwide distribution of Aedes aegypti were tested for their ability to become orally infected with yellow fever virus (YFV). Populations had been analyzed for genetic variations at 11 isozyme loci and assigned to one of 8 genetic geographic groups of Ae. aegypti. Infection rates suggest that populations showing isozyme genetic relatedness also demonstrate similarity to oral infection rates with YFV. The findings support the hypothesis that genetic variation exists for oral susceptibility to YFV in Ae. aegypti.

Mosquito adulticidal properties of Delonix elata (Family: Fabaceae against dengue vector, Aedes aegypti (Diptera: Culicidae

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Mohan Rajeswary

2014-05-01

Full Text Available 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.

Evaluating the Vector Control Potential of the In2Care® Mosquito Trap Against Aedes aegypti and Aedes albopictus Under Semifield Conditions in Manatee County, Florida.

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Buckner, Eva A; Williams, Katie F; Marsicano, Ambyr L; Latham, Mark D; Lesser, Christopher R

2017-09-01

Successful integrated vector management programs may need new strategies in addition to conventional larviciding and adulticiding strategies to target Aedes aegypti and Ae. albopictus, which can develop in small, often cryptic, artificial and natural containers. The In2Care® mosquito trap was recently developed to target and kill larval and adult stages of these invasive container-inhabiting Aedes mosquitoes by utilizing autodissemination. Gravid females that visit the trap pick up pyriproxyfen (PPF) that they later transfer to nearby larval habitats as well as Beauveria bassiana spores that slowly kill them. We assessed the efficacy of the In2Care mosquito trap in a semifield setting against locally sourced strains of Ae. aegypti and Ae. albopictus. We found that the In2Care mosquito trap is attractive to gravid Ae. aegypti and Ae. albopictus females and serves as an egg sink, preventing any adult emergence from the trap (P = 0.0053 for both species). Adult females successfully autodisseminated PPF to surrounding water-filled containers, leading to a statistically significant reduction in new mosquito emergence (P ≤ 0.0002 for both species). Additionally, we found effective contamination with Beauveria bassiana spores, which significantly reduced the survivorship of exposed Ae. aegypti and Ae. albopictus (P ≤ 0.008 for both species in all experimental setups). In summary, the In2Care mosquito trap successfully killed multiple life stages of 2 main mosquito vector species found in Florida under semifield conditions.

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.

Dengue vector dynamics (Aedes aegypti influenced by climate and social factors in Ecuador: implications for targeted control.

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Anna M Stewart Ibarra

Full Text Available BACKGROUND: Dengue fever, a mosquito-borne viral disease, is now the fastest spreading tropical disease globally. Previous studies indicate that climate and human behavior interact to influence dengue virus and vector (Aedes aegypti population dynamics; however, the relative effects of these variables depends on local ecology and social context. We investigated the roles of climate and socio-ecological factors on Ae. aegypti population dynamics in Machala, a city in southern coastal Ecuador where dengue is hyper-endemic. METHODS/PRINCIPAL FINDINGS: We studied two proximate urban localities where we monitored weekly Ae. aegypti oviposition activity (Nov. 2010-June 2011, conducted seasonal pupal surveys, and surveyed household to identify dengue risk factors. The results of this study provide evidence that Ae. aegypti population dynamics are influenced by social risk factors that vary by season and lagged climate variables that vary by locality. Best-fit models to predict the presence of Ae. aegypti pupae included parameters for household water storage practices, access to piped water, the number of households per property, condition of the house and patio, and knowledge and perceptions of dengue. Rainfall and minimum temperature were significant predictors of oviposition activity, although the effect of rainfall varied by locality due to differences in types of water storage containers. CONCLUSIONS: These results indicate the potential to reduce the burden of dengue in this region by conducting focused vector control interventions that target high-risk households and containers in each season and by developing predictive models using climate and non-climate information. These findings provide the region's public health sector with key information for conducting time and location-specific vector control campaigns, and highlight the importance of local socio-ecological studies to understand dengue dynamics. See Text S1 for an executive summary in

Reducing biting rates of Aedes aegypti with metofluthrin: investigations in time and space

OpenAIRE

Darbro, Jonathan M.; Muzari, M. Odwell; Giblin, Arthur; Adamczyk, Rebecca M.; Ritchie, Scott A.; Devine, Gregor J.

2017-01-01

Background Indoor residual spraying is key to dengue control in Cairns and other parts of northern Queensland, Australia, where Aedes aegypti is prevalent, but the strategy faces challenges with regards to slow application time and, therefore, community coverage. A faster potential improvement might be the use of polyethylene netting impregnated with the volatile pyrethroid metofluthrin (SumiOne?). This formulation was assessed in rooms in three houses in Cairns, Australia. One emanator was p...

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

Science.gov (United States)

LaCon, Genevieve; Morrison, Amy C; Astete, Helvio; Stoddard, Steven T; Paz-Soldan, Valerie A; Elder, John P; Halsey, Eric S; Scott, Thomas W; Kitron, Uriel; Vazquez-Prokopec, Gonzalo M

2014-08-01

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 [pentomologic 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 targeting Ae. aegypti hotspots.

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

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Genevieve LaCon

2014-08-01

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

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

CARACTERIZAÇÃO E AVALIAÇÃO DA ATIVIDADE LARVICIDA DO ÓLEO ESSENCIAL DO Zingiber officinale Roscoe (GENGIBRE) FRENTE AO MOSQUITO Aedes aegypti

OpenAIRE

ANDRESON LEANDRO SANTANA SILVA

2012-01-01

Na procura pelo controle químico alternativo contra o mosquito Aedes aegypti, diversas pesquisas são desenvolvidas e estimuladas no intuito de descobrirem novas substâncias inseticidas de origem vegetal. Neste trabalho a partir da extração e do estudo analítico do óleo essencial dos rizomas do Zingiber officinale Roscoe, foi analisado o efeito larvicida do óleo contra larvas em terceiro estágio do mosquito Aedes aegypti (Linnaeus, 1792). Extraiu-se quantitativamente o óleo essencial por hidro...

Aedes aegypti: modelo experimental de atividade biológica de fitoprodutos

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Michele Teixeira Serdeiro

2017-06-01

Full Text Available Aedes aegypti (Linnaeus, 1762 é reconhecido como transmissor de várias arboviroses de importância na saúde pública, como a dengue, zika, chikungunya e febre amarela urbana. O principal método de prevenir a transmissão desses vírus ainda é o controle do mosquito vetor. Produtos naturais de origem vegetal vêm sendo investigados, como mais uma ferramenta no controle de vetores, e compostos menos impactantes ao meio ambiente e a saúde humana. Devido à importância deste culicídeo, buscou-se extrato e frações de C. catharinensis com atividade larvicida sobre Ae. aegypti. O extrato bruto metanólico (EBM e sua fração (EBM 1 obtidos da embaúba foram aplicados no meio de criação das larvas (L3 nas concentrações de 10, 30 e 50 μg/mL. O tratamento com C. cahtarinensis resultou na alteração do período de desenvolvimento larval, pupal e de L3-adulto do mosquito. A mortalidade pupal (25% foi obtida pela fração EBM1. Este estudo demonstrou a eficácia de C. catharinensis sobre o período de desenvolvimento de Ae. aegypti.

Effect of water availability in opening containers of breeding site on Aedes aegypti life cycle

Science.gov (United States)

Tokachil, Najir; Yusoff, Nuraini; Saaid, Alif; Appandi, Najwa; Harun, Farhana

2017-11-01

The distribution of rainfall is one of the factors which contribute to the development of Aedes aegypti life cycle. The fluctuation of rainfall might influence the acceleration of Aedes aegypti growth by providing sufficient breeding sites. In this research, the availability of water in an opening container of the breeding site is considered as a significant variable which affects the distinct stages structure in mosquito life cycle which egg, larva, pupa, and adult. A stage-structured Lefkovitch matrix model was used by considering the quantity of water contains in an opening container and life cycle of Aedes aegypti. The maximum depth of water in the container was also taken into account in order to find the time duration of mosquito life cycle to complete. We found that the maximum depth of water availability in mosquito breeding site influenced the abundance of the mosquito population. Hence, the containers are filled with sufficient water be able to stand from hot temperature for several days before drying out might continue to provide mosquito breeding site. In the future, it is recommended to consider other factors which affect the quantity of water in mosquito breeding sites such as heavy rain and wind blows.

Peningkatan dan aktivitas enzim asetilkolinesterase pada nyamuk Aedes aegypti yang diseleksi dengan malation

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Dwi Jayanti Gunandini

2017-02-01

Full Text Available The Elevated and Activity of Acetilcholinesterase Enzyme on Aedes aegypti Selected by Malathion. The aim of this research was to study the effect of selection by malathion on the activity level  Acetilcholinesterase enzyme on Aedes aegypti mosquitoes. Selection of Aedes aegypti larval by mean of malathion have been conducted for 20 generations. During the selection process time has been increased of concentration applied and exposure. For generation 0-5 (F0-F5, a concentration of 25 µl/l (24 ppm was used to expose the larvae to malathion for five minutes. In generation 6-10 (F6-F10 the concentration has increased to 50 µl/l (48 ppm; in F11-F15 the concentration used was 100 µl/l (96 ppm whereas in F16-F20 200µl/l (192 ppm was used. Mosquito generations that would be regarded as representative and reference groups were F0, F5, F10, F15 and F20. The LC50 of F0, F5, F10, F15 and F20 was 0,025; 0,032; 0,042; 0,062 and 0,071 ppm respectively. Increases LT50 values was also observed in Aedes aegypti selected by malathion. The LT50 of F0, F5, F10, F15 and F20 generations was 7,9; 11,3; 18; 30,6 and 33,1 minutes respectively. The low levels of malathion resistance could be conferred by the elevated of α-esterase. The values of the α-esterase in F0, F5, F10, F15 and F20 were 0,155; 0,174; 0,203; 0,209 and 0,215 µmol/min/mg protein respectively. The acetilcholinesterase activities were also raised in F0, F5, F10, F15 and F20, the value of acetilcholinesterase activities were 20,35; 20,26; 23,14; 23,18 and 24,9%.

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

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Nataly Diniz de Lima Santos

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

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

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Jairo Campos

2003-08-01

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

Molecular and Phytochemical Investigation of Angelica dahurica and Angelica pubescentis Essential Oils and Their Biological Activity against Aedes aegypti, Stephanitis pyrioides, and Colletotrichum Species

Science.gov (United States)

2014-08-18

Molecular and Phytochemical Investigation of Angelica dahurica and Angelica pubescentis Essential Oils and Their Biological Activity against Aedes ...against yellow fever mosquito, Aedes aegypti, and azalea lace bugs, Stephanitis pyrioides, than A. pubescentis root oil. The major compounds in the A...dahurica, Angelica pubescentis, internal transcribed spacer region, Colletotrichum species, Aedes aegypti, Stephanitis pyrioides, 1-dodecanol, 1

Aedes aegypti Larvicidal Sesquiterpene Alkaloids from Maytenus oblongata.

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Touré, Seindé; Nirma, Charlotte; Falkowski, Michael; Dusfour, Isabelle; Boulogne, Isabelle; Jahn-Oyac, Arnaud; Coke, Maïra; Azam, Didier; Girod, Romain; Moriou, Céline; Odonne, Guillaume; Stien, Didier; Houël, Emeline; Eparvier, Véronique

2017-02-24

Four new sesquiterpene alkaloids (1-4) with a β-dihydroagrofuran skeleton and a new triterpenoid (5) were isolated from an ethyl acetate extract of Maytenus oblongata stems. Their structures were elucidated using 1D and 2D NMR spectroscopy as well as MS and ECD experiments. The M. oblongata stem EtOAc extract and the pure compounds isolated were tested for larvicidal activity against Aedes aegypti under laboratory conditions, and compounds 2 and 3 were found to be active.

Technical evaluation of a potential release of OX513A Aedes aegypti mosquitoes on the island of Saba

NARCIS (Netherlands)

Glandorf DCM; GBV; M&V

2017-01-01

The mosquito Aedes aegypti transmits viruses that cause diseases such as dengue, chikungunya and zika. Measures are taken to control the mosquito since these infectious diseases represent a significant health problem. This is the case on the island of Saba, a Dutch Caribbean island. In order to

UJI REPELEN (DAYA TOLAK BEBERAPA EKSTRAK TUMBUHAN TERHADAP GIGITAN NYAMUK Aedes aegypti VEKTOR DEMAM BERDARAH DENGUE

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Hasan Boesri Boesri

2015-10-01

­borne diseases. This research is a pure experiment, that is made some extract and  then its application as repellent for Ae. aegypti, and performed in the Laboratory. Preparation of extracts performed in the laboratory of Pharmacy, University of Gajah Mada, whereas for testing extract to Aedes aegypti conducted in laboratory of insecticide trials in Institute of Vector and Reservoir Control Research and Development. Repellent tests were conducted for some extract plant at 100% dosage and extract which can refuse mosquito bite above 80% per hour  are Zodia leaf extract is resist up to 2 hours as much as 88,2%, tobacco  leaf extract is resist for 3 hours as much as 84,9%, gondopuro leaf  extract for 1 hour resist as much as 83,3%, Serai Wangi leaf extract is resist for 2 hours as much as 85,1%. Clove leaf extract  is resist for 4 hours as much as 81,7%. Chrysanthemum extract for 1 hour resist as much as 89,6%. While the extracts of plant suren leaf, tuba root and lavender just able to resist a bite of Aedes aegypti mosquito under 80%.Keywords : extract, repellent, Aedes aegypti

Adulticidal properties of Pithecellobium dulce (Roxb. Benth. (Family: Fabaceae against dengue vector, Aedes aegypti (Linn. (Diptera: Culicidae

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Mohan Rajeswary

2014-02-01

Full Text Available Objective: To examine the toxicity of mosquito adulticidal activity of different solvent leaf and seed extracts of Pithecellobium dulce (P. dulce against dengue vector, Aedes aegypti (Ae. aegypti. Methods: Adulticidal efficacy of the crude leaf and seed extracts of P. dulce with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the five to six day old adult female mosquitoes of Ae. aegypti. The adult mortality was observed after 24 h under the laboratory conditions. Results: Among the tested solvents the maximum efficacy was observed in the leaf and seed methanol extract. The LC 50 and LC90 values of P. dulce leaf and seed extract against adults of Ae. aegypti were 218.64, 257.99 mg/L and 426.05, 507.73 mg/L, respectively. No mortality was observed in controls. The Chi-square values were significant at P<0.05 level. Conclusions: From the results it can be concluded the crude extract of P. dulce leaf and seed was an excellent potential for controlling dengue vector mosquito, Ae. aegypti.

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

Science.gov (United States)

Dai, Li; Adams, Michael E

2009-05-15

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

Aedes (Stegomyia) aegypti and Aedes (Howardina) cozumelensis in Yucatán State, México, with a summary of published collection records for Ae. cozumelensis.

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García-Rejón, Julián E; López-Uribe, Mildred P; Loroño-Pino, María Alba; Arana-Guardia, Roger; Puc-Tinal, Maria; López-Uribe, Genny M; Coba-Tún, Carlos; Baak-Baak, Carlos M; Machain-Williams, Carlos; Reyes-Solis, Guadalupe C; Lozano-Fuentes, Saul; Saavedra-Rodriguez, Karla; Black, William C; Beaty, Barry J; Eisen, Lars

2012-12-01

We collected mosquito immatures from artificial containers during 2010-2011 from 26 communities, ranging in size from small rural communities to large urban centers, located in different parts of Yucatán State in southeastern México. The arbovirus vector Aedes (Stegomyia) aegypti was collected from all 26 examined communities, and nine of the communities also yielded another container-inhabiting Aedes mosquito: Aedes (Howardina) cozumelensis. The communities from which Ae. cozumelensis were collected were all small rural communities (holes as well as various artificial containers including metal cans, flower vases, buckets, tires, and a water storage tank. The co-occurrence with Ae. aegypti in small rural communities poses intriguing questions regarding linkages between these mosquitoes, including the potential for direct competition for larval development sites. Additional studies are needed to determine how commonly Ae. cozumelensis feeds on human blood and whether it is naturally infected with arboviruses or other pathogens of medical or veterinary importance. We also summarize the published records for Ae. cozumelensis, which are restricted to collections from México's Yucatán Peninsula and Belize, and uniformly represent geographic locations where Ae. aegypti can be expected to occur. © 2012 The Society for Vector Ecology.

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

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Vaea Richard

2016-09-01

Full Text Available 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.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.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.

Avaliação da produtividade dos criadouros do Aedes aegypti (L. e Aedes albopictus (Skuse através dos dados da vigilância em Parati – RJ.

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Eduardo Wermelinger

2012-12-01

Abstract. This study evaluated the pupa-productivity of the entomologic surveillance according methodology used by the official Program for Dengue Control in Brazil (PDCB for Aedes aegypti (Linnaeus and Aedes albopictus (Skuse in Parati, RJ, Brazil. The highest number of A. aegypti pupae were found in drains (31%, bottles and cans (23%; and the highest number of A. albopictus pupae were found in bottles and cans (24%, and plant vases (21%. Of the total pupae identified 84.3% and 79.3% of A. aegypti and A. albopictus respectively were collected in small receptacles: bottles, plants vase, tires, bromeliads and tree holes. These productivities are not supported by literature and can be explained by the restrictions of access for the bigger receptacles and lack of training of the agents. The study points out the importance which the small receptacles can have on vector densities in urban environment despite of their productivity and conclude that the entomology surveillance methodology for dengue used in PDCB has no efficacy to identify the bigger and more productive receptacles. This conclusion suggests that this inefficacy can be an important factor for the failures on dengue vector control in Brazil.

Aedes (Stegomyia) aegypti and Aedes (Howardina) cozumelensis in Yucatán State, México, with a summary of published collection records for Ae. cozumelensis

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García-Rejón, Julián E.; López-Uribe, Mildred P.; Loroño-Pino, María Alba; Arana-Guardia, Roger; Puc-Tinal, Maria; López-Uribe, Genny M.; Coba-Tún, Carlos; Baak-Baak, Carlos M.; Machain-Williams, Carlos; Reyes-Solis, Guadalupe C.; Lozano-Fuentes, Saul; Saavedra-Rodriguez, Karla; Black IV, William C.; Beaty, Barry J.; Eisen, Lars

2012-01-01

We collected mosquito immatures from artificial containers during 2010–2011 from 26 communities, ranging in size from small rural communities to large urban centers, located in different parts of Yucatán State in southeastern México. The arbovirus vector Aedes (Stegomyia) aegypti was collected from all 26 examined communities, and nine of the communities also yielded another container-inhabiting Aedes mosquito: Aedes (Howardina) cozumelensis. The communities from which Ae. cozumelensis were c...

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

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Mohamed Yacoob Syed Ali

2013-06-01

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

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

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Willian Marinho Dourado Coelho

2017-08-01

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

Global risk mapping for major diseases transmitted by Aedes aegypti and Aedes albopictus.

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Leta, Samson; Beyene, Tariku Jibat; De Clercq, Eva M; Amenu, Kebede; Kraemer, Moritz U G; Revie, Crawford W

2018-02-01

The objective of this study was to map the global risk of the major arboviral diseases transmitted by Aedes aegypti and Aedes albopictus by identifying areas where the diseases are reported, either through active transmission or travel-related outbreaks, as well as areas where the diseases are not currently reported but are nonetheless suitable for the vector. Data relating to five arboviral diseases (Zika, dengue fever, chikungunya, yellow fever, and Rift Valley fever (RVF)) were extracted from some of the largest contemporary databases and paired with data on the known distribution of their vectors, A. aegypti and A. albopictus. The disease occurrence data for the selected diseases were compiled from literature dating as far back as 1952 to as recent as 2017. The resulting datasets were aggregated at the country level, except in the case of the USA, where state-level data were used. Spatial analysis was used to process the data and to develop risk maps. Out of the 250 countries/territories considered, 215 (86%) are potentially suitable for the survival and establishment of A. aegypti and/or A. albopictus. A. albopictus has suitability foci in 197 countries/territories, while there are 188 that are suitable for A. aegypti. There is considerable variation in the suitability range among countries/territories, but many of the tropical regions of the world provide high suitability over extensive areas. Globally, 146 (58.4%) countries/territories reported at least one arboviral disease, while 123 (49.2%) reported more than one of the above diseases. The overall numbers of countries/territories reporting autochthonous vector-borne occurrences of Zika, dengue, chikungunya, yellow fever, and RVF, were 85, 111, 106, 43, and 39, respectively. With 215 countries/territories potentially suitable for the most important arboviral disease vectors and more than half of these reporting cases, arboviral diseases are indeed a global public health threat. The increasing proportion of

Persistência e eficácia do regulador de crescimento pyriproxyfen em condições de laboratório para Aedes aegypti Persistence and efficacy of growth regulator pyriproxyfen in laboratory conditions for Aedes aegypti

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Marcelo Carvalho de Resende

2006-02-01

Full Text Available A persistência e a eficácia do regulador de crescimento pyriproxyfen foram testadas em concentrações de 0,01 e 0,05ppm, contra larvas de Aedes aegypti, utilizando os recipientes caixas d'água (45 litros, frascos de vidro (5 litros e baldes de plástico (20 litros. As avaliações foram nos dias 1, 7, 15, 30, 45, 60, 90 e 120 após o tratamento usando larvas de 3º e 4º estádio de Aedes aegypti. Foi calculado o percentual de mortalidade de larvas, pupas e adultos, percentual de inibição de emergência de adulto e duração dos bioensaios. Observou-se que a persistência foi de 45 dias e 90 dias para concentração final de 0,01 e 0,05ppm de pyriproxyfen, respectivamente. Observamos que a mortalidade de pupas foi significativamente maior que a de larvas e de adultos para todos os recipientes e concentrações.The persistence and efficacy of growth regulator pyriproxyfen were evaluated in two final concentrations 0.01 and 0.05ppm against Aedes aegypti larvae in laboratory conditions using three types of containers: cement box (45 liters, glass bottle (5 litersand plastic bucket (20 liters. The tests were carried after 1, 7, 15, 30, 45, 60, 90 and 120 days of treatment against Aedes aegypti larvae 3rd and 4th instar. The percentages of larvae, pupae and adult mortality, the percentage of adult emergence inhibition and time duration of bioassays were calculated. A was observed a persistence of 45 and 90 days by using 0.01 and 0.05ppm final concentrations of pyriproxyfen, respectively, was observed. We observed that mortality in the pupa stage was significantly higher than larvae and adults mortality for all containers and concentrations.

Transcriptome analysis of Aedes aegypti in response to mono-infections and co-infections of dengue virus-2 and chikungunya virus.

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Shrinet, Jatin; Srivastava, Pratibha; Sunil, Sujatha

2017-10-28

Chikungunya virus (CHIKV) and Dengue virus (DENV) spread via the bite of infected Aedes mosquitoes. Both these viruses exist as co-infections in the host as well as the vector and are known to exploit their cellular machinery for their replication. While there are studies reporting the changes in Aedes transcriptome when infected with DENV and CHIKV individually, the effect both these viruses have on the mosquitoes when present as co-infections is not clearly understood. In the present study, we infected Aedes aegypti mosquitoes with DENV and CHIKV individually and as co-infection through nanoinjections. We performed high throughput RNA sequencing of the infected Aedes aegypti to understand the changes in the Aedes transcriptome during the early stages of infection, i.e., 24 h post infection and compared the transcriptome profiles during DENV and CHIKV mono-infections with that of co-infections. We identified 190 significantly regulated genes identified in CHIKV infected library, 37 genes from DENV library and 100 genes from co-infected library and they were classified into different pathways. Our study reveal that distinct pathways and transcripts are being regulated during the three types of infection states in Aedes aegypti mosquitoes. Copyright © 2017 Elsevier Inc. All rights reserved.

Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro. Are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

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Mocellin, Márcio Goulart; Simões, Taynãna César; do Nascimento, Teresa Fernandes Silva; Teixeira, Maria Lucia França; Lounibos, Leon Philip; de Oliveira, Ricardo Lourenço

2012-01-01

Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex) pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07%) and five of Ae. albopictus (0.18%) were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats. PMID:20140379

Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro--are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

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Mocellin, Márcio Goulart; Simões, Taynãna César; Nascimento, Teresa Fernandes Silva do; Teixeira, Maria Lucia França; Lounibos, Leon Philip; Oliveira, Ricardo Lourenço de

2009-12-01

Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex) pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07%) and five of Ae. albopictus(0.18%) were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats.

Bromeliad-inhabiting mosquitoes in an urban botanical garden of dengue endemic Rio de Janeiro - Are bromeliads productive habitats for the invasive vectors Aedes aegypti and Aedes albopictus?

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Márcio Goulart Mocellin

2009-12-01

Full Text Available Immatures of both Aedes aegypti and Aedes albopictus have been found in water-holding bromeliad axils in Brazil. Removal of these plants or their treatment with insecticides in public and private gardens have been undertaken during dengue outbreaks in Brazil despite uncertainty as to their importance as productive habitats for dengue vectors. From March 2005-February 2006, we sampled 120 randomly selected bromeliads belonging to 10 species in a public garden less than 200 m from houses in a dengue-endemic neighborhood in Rio de Janeiro. A total of 2,816 mosquito larvae and pupae was collected, with an average of 5.87 immatures per plant per collection. Culex (Microculex pleuristriatus and Culex spp of the Ocellatus Group were the most abundant culicid species, found in all species of bromeliads; next in relative abundance were species of the genus Wyeomyia. Only two individuals of Ae. aegypti (0.07% and five of Ae. albopictus(0.18% were collected from bromeliads. By contrast, immatures of Ae. aegypti were found in manmade containers in nearly 5% of nearby houses. These results demonstrate that bromeliads are not important producers of Ae. aegypti and Ae. albopictus and, hence, should not be a focus for dengue control. However, the results of this study of only one year in a single area may not represent outcomes in other urban localities where bromeliads, Ae. aegypti and dengue coincide in more disturbed habitats.

Effects of insemination and blood-feeding on locomotor activity of Aedes albopictus and Aedes aegypti (Diptera: Culicidae) females under laboratory conditions.

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Lima-Camara, Tamara Nunes; Lima, José Bento Pereira; Bruno, Rafaela Vieira; Peixoto, Alexandre Afranio

2014-07-02

Dengue is an arbovirus disease transmitted by two Aedes mosquitoes: Ae. aegypti and Ae. albopictus. Virgin females of these two species generally show a bimodal and diurnal pattern of activity, with early morning and late afternoon peaks. Although some studies on the flight activity of virgin, inseminated and blood-fed Ae. aegypti females have been carried out under laboratory conditions, little is known about the effects of such physiological states on the locomotor activity of Ae. albopictus and Ae. aegypti females. The aim of this study was to analyze, under laboratory conditions, the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under LD 12:12, at 25°C. Both Ae. albopictus and Ae. aegypti females were obtained from established laboratory colonies. Control groups were represented by virgin/unfed Ae. albopictus and Ae. aegypti females. Experiments were conducted under laboratory conditions, using an activity monitor that registers individual activity every thirty minutes. Virgin/unfed Ae. albopictus and Ae. aegypti females showed a diurnal and bimodal pattern of locomotor activity, with peaks at early morning and late afternoon. Insemination and blood-feeding significantly decreased the locomotor activity of Ae. aegypti females, but inseminated/blood-fed Ae. aegypti and Ae. albopictus females showed a similar significant decrease on the locomotor activity compared to virgin/unfed females. This study is the first demonstration of the effects of insemination and blood-feeding on the locomotor activity of Ae. albopictus and Ae. aegypti females under artificial conditions. Data suggest that Ae. albopictus and Ae. aegypti females respond in different ways to physiological status changes and such divergence between these two dengue vectors, associated with several ecological differences, could be related to the greater dengue vectorial capacity of Ae. aegypti in Americas in comparison to Ae. albopictus.

Patterns of geographic expansion of Aedes aegypti in the Peruvian Amazon.

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Sarah Anne Guagliardo

2014-08-01

Full Text Available In the Peruvian Amazon, the dengue vector Aedes aegypti is abundant in large urban centers such as Iquitos. In recent years, it has also been found in a number of neighboring rural communities with similar climatic and socioeconomic conditions. To better understand Ae. aegypti spread, we compared characteristics of communities, houses, and containers in infested and uninfested communities.We conducted pupal-demographic surveys and deployed ovitraps in 34 communities surrounding the city of Iquitos. Communities surveyed were located along two transects: the Amazon River and a 95 km highway. We calculated entomological indices, mapped Ae. aegypti presence, and developed univariable and multivariable logistic regression models to predict Ae. aegypti presence at the community, household, or container level.Large communities closer to Iquitos were more likely to be infested with Ae. aegypti. Within infested communities, houses with Ae. aegypti had more passively-filled containers and were more often infested with other mosquito genera than houses without Ae. aegypti. For containers, large water tanks/drums and containers with solar exposure were more likely to be infested with Ae. aegypti. Maps of Ae. aegypti presence revealed a linear pattern of infestation along the highway, and a scattered pattern along the Amazon River. We also identified the geographical limit of Ae. aegypti expansion along the highway at 19.3 km south of Iquitos.In the Peruvian Amazon, Ae. aegypti geographic spread is driven by human transportation networks along rivers and highways. Our results suggest that urban development and oviposition site availability drive Ae. aegypti colonization along roads. Along rivers, boat traffic is likely to drive long-distance dispersal via unintentional transport of mosquitoes on boats.

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

International Nuclear Information System (INIS)

Read, N.G.

1980-01-01

Newly emerged mosquitoes (Aedes aegypti (L)) were exposed to doses of 500 to 32,000 rad X-irradiation and the LD 50 and mean survival time determined. Radiation doses between 500 and 8,000 rad had only a slight effect on longevity whereas exposure to 32,000 had an appreciable effect. The midgut structure of newly emerged, X-irradiated female Aedes aegypti imagines was examined at set intervals after irradiation. The cytochemical localization of midgut acid phosphatase, alkaline phosphatase and adenosine triphosphatase, and also quantitative estimates of midgut acid and alkaline phosphatase were carried out on mosquitoes exposed to 32,000 rad. Considerable changes in the structure of the midgut cells were apparent. With 500, 4,000 and 8,000 rad there was evidence of cellular repair and recovery. However, with 32,000 rad cellular damage was most extensive, with considerable loss of cell structure. The ultrastructural changes noted suggest that the primary radiation damage was to the plasma and organelle membranes, which is in agreement with the membrane-damage/enzyme release hypothesis. (author)

H+ V-ATPase-Energized Transporters in Brush Border Membrane Vesicles from Whole Larvae of Aedes Aegypti

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Brush Border Membrane vesicles (BBMVs) from Whole larvae of Aedes aegypti (AeBBMVWs ) contain an H+ V-ATPase (V), a Na+/H+ antiporter, NHA1 (A) and a Na+-coupled, nutrient amino acid transporter, NAT8 (N), VAN for short. All V-ATPase subunits are present in the Ae. aegypti genome and in the vesicles...

The Aquaporin gene family of the yellow fever mosquito, Aedes aegypti.

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Lisa L Drake

2010-12-01

Full Text Available The mosquito, Aedes aegypti, is the principal vector of the Dengue and yellow fever viruses. During feeding, an adult female can take up more than its own body weight in vertebrate blood. After a blood meal females excrete large amounts of urine through their excretion system, the Malpighian tubules (MT. Diuresis starts within seconds after the mosquito starts feeding. Aquaporins (AQPs are a family of membrane transporters that regulate the flow of water, glycerol and other small molecules across cellular membranes in both prokaryotic and eukaryotic cells. Our aim was to identify aquaporins that function as water channels, mediating transcellular water transport in MTs of adult female Ae. aegypti.Using a bioinformatics approach we screened genome databases and identified six putative AQPs in the genome of Ae. aegypti. Phylogenetic analysis showed that five of the six Ae. aegypti AQPs have high similarity to classical water-transporting AQPs of vertebrates. Using microarray, reverse transcription and real time PCR analysis we found that all six AQPs are expressed in distinct patterns in mosquito tissues/body parts. AaAQP1, 4, and 5 are strongly expressed in the adult female MT. RNAi-mediated knockdown of the MT-expressed mosquito AQPs resulted in significantly reduced diuresis.Our results support the notion that AQP1, 4, and 5 function as water transporters in the MTs of adult female Ae. aegypti mosquitoes. Our results demonstrate the importance of these AQPs for mosquito diuresis after blood ingestion and highlight their potential as targets for the development of novel vector control strategies.

The Aquaporin gene family of the yellow fever mosquito, Aedes aegypti.

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Drake, Lisa L; Boudko, Dmitri Y; Marinotti, Osvaldo; Carpenter, Victoria K; Dawe, Angus L; Hansen, Immo A

2010-12-29

The mosquito, Aedes aegypti, is the principal vector of the Dengue and yellow fever viruses. During feeding, an adult female can take up more than its own body weight in vertebrate blood. After a blood meal females excrete large amounts of urine through their excretion system, the Malpighian tubules (MT). Diuresis starts within seconds after the mosquito starts feeding. Aquaporins (AQPs) are a family of membrane transporters that regulate the flow of water, glycerol and other small molecules across cellular membranes in both prokaryotic and eukaryotic cells. Our aim was to identify aquaporins that function as water channels, mediating transcellular water transport in MTs of adult female Ae. aegypti. Using a bioinformatics approach we screened genome databases and identified six putative AQPs in the genome of Ae. aegypti. Phylogenetic analysis showed that five of the six Ae. aegypti AQPs have high similarity to classical water-transporting AQPs of vertebrates. Using microarray, reverse transcription and real time PCR analysis we found that all six AQPs are expressed in distinct patterns in mosquito tissues/body parts. AaAQP1, 4, and 5 are strongly expressed in the adult female MT. RNAi-mediated knockdown of the MT-expressed mosquito AQPs resulted in significantly reduced diuresis. Our results support the notion that AQP1, 4, and 5 function as water transporters in the MTs of adult female Ae. aegypti mosquitoes. Our results demonstrate the importance of these AQPs for mosquito diuresis after blood ingestion and highlight their potential as targets for the development of novel vector control strategies.

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

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Crosson, W. L.; Eisen, L.; Estes, M. G.; Estes, S. M.; Hayden, M.; Lozano-Fuentes, S.; Monaghan, A. J.; Moreno Madriñán, M. J.; Ochoa, C.; Quattrochi, D.; Tapia, B.; Welsh-Rodriguez, C. M.

2012-12-01

In tropical and sub-tropical regions, the mosquito Aedes aegypti is the major vector for the virus causing dengue, a serious public health issue in these areas. Through ongoing NSF- and NASA-funded studies, field surveys of Aedes aegypti and an integrated modeling approach are being used to improve our understanding of the potential range of the mosquito to expand toward heavily populated high elevation areas such as Mexico City under various climate change and socio-economic scenarios. This work serves three primary objectives: (1) Employ NASA remotely-sensed data to supplement the environmental monitoring and modeling component of the project. These data -- for example, surface temperature, precipitation, vegetation indices, soil moisture and elevation -- are critical for understanding the habitat necessary for mosquito survival and abundance; (2) Implement training sessions to instruct scientists and students from Mexico and the U.S. on how to use remote sensing and implement the NASA SERVIR Regional Visualization and Monitoring System; (3) Employ the SERVIR framework to optimize the dissemination of key project results in order to increase their societal relevance and benefits in developing climate adaptation strategies. Field surveys of larval, pupal and adult Aedes aegypti, as well as detailed physical and social household characteristics, were conducted in the summers of 2011and 2012 at geographic scales from the household to the community along a transect from sea level to 2400 m ASL. These data are being used in models to estimate Aedes aegypti habitat suitability. In 2011, Aedes aegypti were identified at an elevation of over 2150 m in Puebla, the highest elevation at which this species has been observed.

Spatial patterns of high Aedes aegypti oviposition activity in northwestern Argentina.

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Elizabet Lilia Estallo

Full Text Available BACKGROUND: In Argentina, dengue has affected mainly the Northern provinces, including Salta. The objective of this study was to analyze the spatial patterns of high Aedes aegypti oviposition activity in San Ramón de la Nueva Orán, northwestern Argentina. The location of clusters as hot spot areas should help control programs to identify priority areas and allocate their resources more effectively. METHODOLOGY: Oviposition activity was detected in Orán City (Salta province using ovitraps, weekly replaced (October 2005-2007. Spatial autocorrelation was measured with Moran's Index and depicted through cluster maps to identify hot spots. Total egg numbers were spatially interpolated and a classified map with Ae. aegypti high oviposition activity areas was performed. Potential breeding and resting (PBR sites were geo-referenced. A logistic regression analysis of interpolated egg numbers and PBR location was performed to generate a predictive mapping of mosquito oviposition activity. PRINCIPAL FINDINGS: Both cluster maps and predictive map were consistent, identifying in central and southern areas of the city high Ae. aegypti oviposition activity. A logistic regression model was successfully developed to predict Ae. aegypti oviposition activity based on distance to PBR sites, with tire dumps having the strongest association with mosquito oviposition activity. A predictive map reflecting probability of oviposition activity was produced. The predictive map delimitated an area of maximum probability of Ae. aegypti oviposition activity in the south of Orán city where tire dumps predominate. The overall fit of the model was acceptable (ROC=0.77, obtaining 99% of sensitivity and 75.29% of specificity. CONCLUSIONS: Distance to tire dumps is inversely associated with high mosquito activity, allowing us to identify hot spots. These methodologies are useful for prevention, surveillance, and control of tropical vector borne diseases and might assist

Oral susceptibility of Singapore Aedes (Stegomyia aegypti (Linnaeus to Zika virus.

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MeiZhi Irene Li

Full Text Available Zika virus (ZIKV is a little known flavivirus that caused a major outbreak in 2007, in the South-western Pacific Island of Yap. It causes dengue-like syndromes but with milder symptoms. In Africa, where it was first isolated, ZIKV is mainly transmitted by sylvatic Aedes mosquitoes. The virus has also been isolated from Ae. aegypti and it is considered to be the vector involved in the urban transmission of the virus. Transmission of the virus by an African strain of Ae. aegypti has also been demonstrated under laboratory conditions. The aim of the present study is to describe the oral susceptibility of a Singapore strain of Ae. aegypti to ZIKV, under conditions that simulate local climate.To assess the receptivity of Singapore's Ae. aegypti to the virus, we orally exposed a local mosquito strain to a Ugandan strain of ZIKV. Upon exposure, fully engorged mosquitoes were maintained in an environmental chamber set at 29 °C and 70-75% RH. Eight mosquitoes were then sampled daily from day 1 to day 7, and subsequently on days 10 and 14 post exposure (pe. The virus titer of the midgut and salivary glands of each mosquito were determined using a tissue culture infectious dose(50 (TCID(50 assay. High midgut infection and salivary gland dissemination rates were observed. By day 5 after the infectious blood meal, ZIKV was found in the salivary glands of more than half of the mosquitoes tested (62%; and by day 10, all mosquitoes were potentially infective.This study showed that Singapore's urban Ae. aegypti are susceptible and are potentially capable of transmitting ZIKV. The virus could be established in Singapore should it be introduced. Nevertheless, Singapore's current dengue control strategy is applicable to control ZIKV.

Dengue-1 virus and vector competence of Aedes aegypti (Diptera: Culicidae) populations from New Caledonia.

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Calvez, Elodie; Guillaumot, Laurent; Girault, Dominique; Richard, Vaea; O'Connor, Olivia; Paoaafaite, Tuterarii; Teurlai, Magali; Pocquet, Nicolas; Cao-Lormeau, Van-Mai; Dupont-Rouzeyrol, Myrielle

2017-08-09

Dengue virus (DENV) is the arbovirus with the highest incidence in New Caledonia and in the South Pacific region. In 2012-2014, a major DENV-1 outbreak occurred in New Caledonia. The only known vector of DENV in New Caledonia is Aedes aegypti but no study has yet evaluated the competence of New Caledonia Ae. aegypti populations to transmit DENV. This study compared the ability of field-collected Ae. aegypti from different locations in New Caledonia to transmit the DENV-1 responsible for the 2012-2014 outbreak. This study also aimed to compare the New Caledonia results with the vector competence of Ae. aegypti from French Polynesia as these two French countries have close links, including arbovirus circulation. Three wild Ae. aegypti populations were collected in New Caledonia and one in French Polynesia. Female mosquitoes were orally exposed to DENV-1 (10 6 FFU/ml). Mosquito bodies (thorax and abdomen), heads and saliva were analyzed to measure infection, dissemination, transmission rates and transmission efficiency, at 7, 14 and 21 days post-infection (dpi), respectively. DENV-1 infection rates were heterogeneous, but dissemination rates were high and homogenous among the three Ae. aegypti populations from New Caledonia. Despite this high DENV-1 dissemination rate, the transmission rate, and therefore the transmission efficiency, observed were low. Aedes aegypti population from New Caledonia was less susceptible to infection and had lower ability to transmit DENV-1 than Ae. aegypti populations from French Polynesia. This study suggests that even if susceptible to infection, the New Caledonian Ae. aegypti populations were moderately competent vectors for DENV-1 strain from the 2012-2014 outbreak. These results strongly suggest that other factors might have contributed to the spread of this DENV-1 strain in New Caledonia and in the Pacific region.

Plano amostral para cálculo de densidade larvária de Aedes aegypti e Aedes albopictus no Estado de São Paulo, Brasil Sampling desing for larval density computation of Aedes Aegypti and Aedes albopictus in the State of S. Paulo, Brazil

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Maria Cecília G.P. Alves

1991-08-01

Full Text Available O Programa de Controle de Vetores de Febre Amarela e Dengue, desenvolvido pela Superintendência de Controle de Endemias do Estado de São Paulo, Brasil, prevê a realização de pesquisa para avaliação da densidade larvária de Aedes aegypti e Aedes albopictus em edificações de municípios com infestação domiciliar. Descreve-se o plano amostral que vem sendo aplicado, desde outubro de 1987, nos municípios da Região de Presidente Prudente. Para acompanhamento da densidade está sendo utilizado o índice de Breteau. São sorteados, nos municípios infestados, mensalmente e de forma independente, amostras de edificações para a obtenção das estimativas do índice. O plano amostral prevê a seleção de conglomerados em 2 estágios: quadras e edificações. O tamanho da amostra foi definido estimando-se o coeficiente da correlação intraconglomerado e variância relativa por elemento através de pesquisas realizadas anteriormente em municípios do Serviço Regional de São José do Rio Preto. O plano propõe que os valores relativos ao tamanho da amostra sejam atualizados periodicamente em função dos valores obtidos para o estimador do Índice de Breteau e sua variância, em meses anteriores.The Yellow Fever and Dengue Vector Control Program developed by the Superintendency for the Control of Endemic Diseases in the State of S. Paulo recommends Aedes aegypti and Aedes albopictus larval density monitoring in cities with domiciliar infestation. The sampling plan which has been applied in the countries of the Presidente Prudente region (SP- Brazil since 1987 is described. The infestation is measured by using the Breteau Index. A sample of buildings is drawn, monthly and independently, in the infested cities, in which measurements are to be made. The sample is stratified and the elementary unit selection is made by using two-stage cluster sampling: of blocks and buildings. The sample sizes were defined using the coefficient of variation

Dengue Virus Infection of Aedes aegypti Requires a Putative Cysteine Rich Venom Protein.

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Berlin Londono-Renteria

2015-10-01

Full Text Available Dengue virus (DENV is a mosquito-borne flavivirus that causes serious human disease and mortality worldwide. There is no specific antiviral therapy or vaccine for DENV infection. Alterations in gene expression during DENV infection of the mosquito and the impact of these changes on virus infection are important events to investigate in hopes of creating new treatments and vaccines. We previously identified 203 genes that were ≥5-fold differentially upregulated during flavivirus infection of the mosquito. Here, we examined the impact of silencing 100 of the most highly upregulated gene targets on DENV infection in its mosquito vector. We identified 20 genes that reduced DENV infection by at least 60% when silenced. We focused on one gene, a putative cysteine rich venom protein (SeqID AAEL000379; CRVP379, whose silencing significantly reduced DENV infection in Aedes aegypti cells. Here, we examine the requirement for CRVP379 during DENV infection of the mosquito and investigate the mechanisms surrounding this phenomenon. We also show that blocking CRVP379 protein with either RNAi or specific antisera inhibits DENV infection in Aedes aegypti. This work identifies a novel mosquito gene target for controlling DENV infection in mosquitoes that may also be used to develop broad preventative and therapeutic measures for multiple flaviviruses.

Oral susceptibility of Aedes aegypti (Diptera: Culicidae) from Senegal for dengue serotypes 1 and 3 viruses.

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Gaye, Alioune; Faye, Oumar; Diagne, Cheikh T; Faye, Ousmane; Diallo, Diawo; Weaver, Scott C; Sall, Amadou A; Diallo, Mawlouth

2014-11-01

To investigate the potential for domestic and wild populations of Aedes aegypti from Dakar and Kedougou to develop a disseminated infection after exposure to DENV-3 and DENV-1. We have exposed sylvatic and urban population of Ae. aegypti from Senegal to bloomeals containing dengue serotype 1 and 3. At different incubation period, individual mosquito legs/wings and bodies were tested for virus presence using real time RT-PCR to estimate the infection and dissemination rates. The data indicated low susceptibility to DENV-3 (infection: 2.4-15.2%, and dissemination rates: 0-8.3%) and higher susceptibility to DENV-1 (infection and dissemination rates up to 50%). Aedes aegypti from Senegal seem able to develop a disseminated infection of DENV-1 and DENV-3. Further studies are needed to test their ability to transmit the two serotypes. © 2014 John Wiley & Sons Ltd.

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

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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.

Intersectoral coordination in Aedes aegypti control. A pilot project in Havana City, Cuba.

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Sanchez, L; Perez, D; Pérez, T; Sosa, T; Cruz, G; Kouri, G; Boelaert, M; Van der Stuyft, P

2005-01-01

Background The 55th World Health Assembly declared dengue prevention and control a priority and urged Member States to develop sustainable intersectoral strategies to this end. To provide evidence for the reorientation of the dengue prevention policy in Cuba, we launched an intervention study to document the effectiveness of a local-level intersectoral approach. We used a quasi-experimental design. Social scientists introduced participatory methods to facilitate dialogue in the biweekly meetings of the intersectoral Health Council of the intervention area. This council subsequently developed an intersectoral plan for dengue prevention, of which the core objective was to design and implement activities for communication and social mobilization. In the control area, routine dengue control activities continued without additional input. Knowledge, attitudes and perceptions of dengue, and entomological indices were compared inside and between the areas before and after the 1-year intervention period. In the intervention area the Health Council elaborated an intersectoral plan for dengue prevention focused on source reduction. The Aedes aegypti control methods consisted in eliminating useless containers in the houses and surroundings, covering tanks, and cleaning public and inhabited areas. It was implemented through communication and social mobilization. The Health Council in the control area occasionally discussed dengue issues but did not develop a coordinated action plan. Good knowledge about breeding sites and disease symptoms increased significantly (by 49.7% and 17.1% respectively) in the intervention area as well as the proportion of respondents eliminating containers in and around their houses (by 44%). No changes were observed in the control area. The House Index in the intervention area was 3.72% at baseline and decreased to 0.61% after 1 year. In the control area it remained stable throughout the study period (1.31% and 1.65% respectively). The introduction

Adulticidal properties of Pithecellobium dulce (Roxb.) Benth. (Family: Fabaceae) against dengue vector, Aedes aegypti (Linn.) (Diptera: Culicidae)

OpenAIRE

Mohan Rajeswary; Marimuthu Govindarajan

2014-01-01

Objective: To examine the toxicity of mosquito adulticidal activity of different solvent leaf and seed extracts of Pithecellobium dulce (P. dulce) against dengue vector, Aedes aegypti (Ae. aegypti). Methods: Adulticidal efficacy of the crude leaf and seed extracts of P. dulce with five different solvents like benzene, hexane, ethyl acetate, methanol and chloroform was tested against the five to six day old adult female mosquitoes of Ae. aegypti. The adult mortality was observed...

Targeted genome editing in Aedes aegypti using TALENs.

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Aryan, Azadeh; Myles, Kevin M; Adelman, Zach N

2014-08-15

The Culicine mosquito, Aedes aegypti, is both a major vector of arthropod-borne viruses (arboviruses) and a genetic model organism for arbovirus transmission. TALE nucleases (TALENs), a group of artificial enzymes capable of generating site-specific DNA lesions, consist of a non-specific FokI endonuclease cleavage domain fused to an engineered DNA binding domain specific to a target site. While TALENs have become an important tool for targeted gene disruption in a variety of organisms, application to the mosquito genome is a new approach. We recently described the use of TALENs to perform heritable genetic disruptions in A. aegypti. Here, we provide detailed methods that will allow other research laboratories to capitalize on the potential of this technology for understanding mosquito gene function. We describe target site selection, transient embryo-based assays to rapidly assess TALEN activity, embryonic microinjection and downstream screening steps to identify target site mutations. Copyright © 2014 Elsevier Inc. All rights reserved.

Evaluación de recursos vegetales biocidas en el control de estadios inmaduros de aedes aegypti l. Trujillo, la libertad, Perú, 2006 - 2007

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Bobadilla Alvarez, Miguel Constante

2007-01-01

In Peru and around the world the most important disease-borne vector which causes dengue fever and yellow fever is Aedes aegypti L. The control measures during its cycle of life involve the use of conventional chemical insecticides, biologic control and botanical extracts. With the aim to rescue a validation of biocide plants in the Trujillo community population to avoid the seasonal raise of dengue fever in summer months, a control on fourth instar larvae and pupae of this mosquito using lea...

Evaluation of Aedes Aegypti Presence and Abundance in Septic Tanks and Their Impacts on Dengue Transmission

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2009-03-10

aforementioned applications, GIS has been used for cost analysis decisions in vector control planning . GIS software was used to remotely identify... plan for dengue outbreaks, a contingency plan to hospitalize large numbers of dengue hemorrhagic patients if necessary, education of the medical...de nicho en tres culicidae urbanos (Culex fatigans Weid, C. coringer Theo, y Aedes aegypti L.) en el cemeterio de Caracas. Acta Cientifica

Spatial Models for Prediction and Early Warning of Aedes aegypti Proliferation from Data on Climate Change and Variability in Cuba.

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Ortiz, Paulo L; Rivero, Alina; Linares, Yzenia; Pérez, Alina; Vázquez, Juan R

2015-04-01

Climate variability, the primary expression of climate change, is one of the most important environmental problems affecting human health, particularly vector-borne diseases. Despite research efforts worldwide, there are few studies addressing the use of information on climate variability for prevention and early warning of vector-borne infectious diseases. Show the utility of climate information for vector surveillance by developing spatial models using an entomological indicator and information on predicted climate variability in Cuba to provide early warning of danger of increased risk of dengue transmission. An ecological study was carried out using retrospective and prospective analyses of time series combined with spatial statistics. Several entomological and climatic indicators were considered using complex Bultó indices -1 and -2. Moran's I spatial autocorrelation coefficient specified for a matrix of neighbors with a radius of 20 km, was used to identify the spatial structure. Spatial structure simulation was based on simultaneous autoregressive and conditional autoregressive models; agreement between predicted and observed values for number of Aedes aegypti foci was determined by the concordance index Di and skill factor Bi. Spatial and temporal distributions of populations of Aedes aegypti were obtained. Models for describing, simulating and predicting spatial patterns of Aedes aegypti populations associated with climate variability patterns were put forward. The ranges of climate variability affecting Aedes aegypti populations were identified. Forecast maps were generated for the municipal level. Using the Bultó indices of climate variability, it is possible to construct spatial models for predicting increased Aedes aegypti populations in Cuba. At 20 x 20 km resolution, the models are able to provide warning of potential changes in vector populations in rainy and dry seasons and by month, thus demonstrating the usefulness of climate information for

Scanning electron microscopy of the four larval instars of the Dengue fever vector Aedes aegypti (Diptera: Culicidae

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Stefan Schaper

2006-09-01

Full Text Available Aedes aegypti is the main insect vector of Dengue fever and dengue hemorrhagic fever/dengue shock syndrome and represents the only vulnerable element in the control of this disease. Therefore, the identification and quantification of this mosquito is an important task; however, the majority of taxonomic keys are based on the 4th larval instar. For that reason, this study describes the four larval instars of A. aegypti using scanning electron microscopy. Morphological changes during larval development were observed at the pecten, comb scales and the ventral brush of the abdominal segment X; however, the 3rd and 4th instars showed similar structures with only a slight variation. The structures described in this study will be helpful in the identification of the four instars of A. aegypti, a fundamental task for comprehending the natural history of dengue mainly in new territories affected. Rev. Biol. Trop. 54 (3: 847-852. Epub 2006 Sept. 29.Aedes aegypti es el principal insecto vector de la fiebre del dengue y del dengue hemorrágico/síndrome del choque por dengue y es el único elemento atacable para el control de esta virosis. La identificación y cuantificación de éste es una tarea importante; no obstante, la mayoría de las llaves taxonómicas se basan en el cuarto estadio larval. Por esta razón, en este trabajo se describen los cuatro estadios larvales de A. aegypti los cuales fueron examinados mediante microscopia electrónica de rastreo. Los cambios morfológicos ocurridos durante el desarrollo larval fueron observados en el pecten, las escamas del peine, el cepillo ventral del décimo segmento. El 3ero y 4to estadios larvales mostraron estructuras similares con sólo ligeras variaciones. Las estructuras descritas en este artículo permiten identificar cualquiera de los cuatro estadios larvales de A. aegypti, lo cual representa una tarea importante en la comprensión de la historia natural del dengue en los nuevos territorios afectados.

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

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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. 

Evaluación de la resistencia a insecticidas de una cepa de Aedes aegypti de El Salvador Assessing the insecticide resistance of an Aedes aegypti strain in El Salvador

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Juan A. Bisset Lazcano

2009-09-01

Full Text Available OBJETIVOS: Evaluar el nivel de susceptibilidad a insecticidas de una cepa de Aedes aegypti procedente de El Salvador y describir los posibles mecanismos de resistencia al temefós. MÉTODOS: Se evaluó una cepa de A. aegypti procedente del municipio de Soyapango, departamento de San Salvador, El Salvador. Mediante bioensayos se determinó la susceptibilidad de las larvas al insecticida organofosforado temefós y a tres piretroides (deltametrina, lambdacialotrina y cipermetrina y de los adultos a un insecticida organofosforado (clorpirifós. Se determinó el factor de resistencia (FR50 con respecto a una cepa sensible de referencia (Rockefeller. Se estableció el mecanismo de resistencia al temefós mediante el empleo de sustancias sinergistas, ensayos bioquímicos de actividad enzimática y zimogramas en gel de poliacrilamida. RESULTADOS: Las larvas de la cepa estudiada mostraron una alta resistencia al temefós (FR50 = 24,16. De las enzimas analizadas, se encontró que solo la esterasa A4 estaba vinculada al mecanismo de resistencia al temefós. Los mosquitos adultos resultaron susceptibles a la lambdacialotrina y al clorpirifós y su resistencia a la deltametrina y la cipermetrina quedó en la categoría de verificación. CONCLUSIONES: La resistencia al temefós podría reducir la eficacia del control químico del mosquito A. aegypti en la zona estudiada de El Salvador. Los insecticidas clorpirifós, lambdacialotrina y cipermetrina son buenos candidatos alternativos a utilizar en las nuevas intervenciones de control de este vector.OBJECTIVES: To assess the level of insecticide susceptibility of a certain Aedes aegypti strain found in El Salvador and to explain the mechanisms for its resistance to temephos. METHODS: An A. aegypti strain from the municipality of Soyapango, Department of San Salvador, El Salvador, was studied. Bioassays were used to determine the susceptibility of the larvae to the organophosphate insecticide temephos and to

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

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Riyani Setiyaningsih

2014-06-01

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

Risk of transmission of viral haemorrhagic fevers and the insecticide susceptibilitystatus of aedes aegypti (linnaeus) in some sites in Accra, Ghana.

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Suzuki, Takashi; Osei, Joseph H; Sasaki, Akihiro; Adimazoya, Michelle; Appawu, Maxwell; Boakye, Daniel; Ohta, Nobuo; Dadzie, Samuel

2016-09-01

Dengue is one of the emerging diseases that can mostly only be controlled by vector control since there is no vaccine for the disease. Although, Dengue has not been reported in Ghana, movement of people from neighbouring countries where the disease has been reported can facilitate transmission of the disease. This study was carried on the University of Ghana campus to determine the risk of transmission of viral haemorrhagic fevers and the insecticide susceptibility status of Ae. aegypti in some sites in Accra, Ghana. Larval surveys were carried to inspect containers within households and estimate larval indices and adult Aedes mosquitoes were collected using human landing collection technique. WHO tube assays was used to assess the insecticide susceptibility status of Aedes mosquitoes. Ae. aegypti were the most prevalent species, 75.5% and followed by Ae. vittatus , 23.9 %. Ae. albopictus and Ae. granti were in smaller numbers. Household index (HI), Breteau index (BI), and container index were calculated as 8.2%, 11.2% and 10.3% respectively with man-vector contact rate of 0.67 bites/man-hour estimated for the area. The mortalities recorded for Ae. aegypti from WHO tube assays was 88%, 94%, 80% and 99% for DDT (4%), deltamethrin (0.05%), lambdacyhalothrin (0.05%) and permethrin (0.75%) respectively. The survey results indicated that the density of Aedes mosquitoes was considered to be sufficient to promote an outbreak of viral haemorrhagic fevers on Legon Campus. Aedes mosquitoes were found to be resistant to DDT, deltamethrin and lamdacyhalothrin, but susceptible to permethrin. This study was supported in part by Japan Initiative for Global Research Network on Infectious Diseases (J-Grid).

Aedes aegypti uses RNA interference in defense against Sindbis virus infection.

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Campbell, Corey L; Keene, Kimberly M; Brackney, Douglas E; Olson, Ken E; Blair, Carol D; Wilusz, Jeffrey; Foy, Brian D

2008-03-17

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). 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. 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.

Improving the delivery and efficiency of fungus-impregnated cloths for control of adult Aedes aegypti using a synthetic attractive lure.

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Paula, Adriano R; Silva, Leila E I; Ribeiro, Anderson; Butt, Tariq M; Silva, Carlos P; Samuels, Richard I

2018-05-04

Entomopathogenic fungi are highly promising agents for controlling Aedes aegypti mosquitoes. Deploying fungus-impregnated black cloths in PET traps efficiently reduced Ae. aegypti female survival rates under intra-domicile conditions. With the aim of further increasing the effectiveness of the traps, the addition of attractive lures to fungus-impregnated traps was evaluated. Black cloths were suspended inside 2 l plastic bottles called "PET traps". These traps were placed in rooms simulating human residences. The first experiments evaluated the attraction of mosquitoes to PET traps with black cloths covered in adhesive film with and without synthetic lures (AtrAedes™). Traps were left in the test rooms for either 24 or 48 h. The attractiveness of the lures over time was also evaluated. The efficiency of PET traps with fungus-impregnated black cloths associated with lures was compared to that of traps without lures. The highest percentage of captured mosquitoes (31 and 66%) were observed in PET traps with black cloths covered in adhesive film + attractive lure maintained in test rooms for 24 h and 48 h, respectively. Black cloths covered in adhesive film captured 17 or 36% of the mosquitoes at 24 h and 48 h, respectively. The attractiveness of the lures fell gradually over time, capturing 37% after 5 days on the bench and 22% of the mosquitoes after 30 days exposure to ambient conditions. Associating attractive synthetic lures with black cloths impregnated with M. anisopliae placed in test rooms for 120 h reduced mean survival to 32%, whilst black cloths impregnated with M. anisopliae without lures resulted in a 48% survival rate. Using Beauveria bassiana in the traps resulted in a 52% reduction in mosquito survival, whilst combining Beauveria and AtrAedes resulted in a 36% survival rate. PET traps impregnated with fungus + AtrAedes resulted in similar reductions in survival when left in the rooms for 24, 48, 72 or 120 h. AtrAedes increased attractiveness of PET

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

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Nildimar Alves Honório

2003-03-01

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

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

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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.

Potential control of Aedes aegypti (Diptera: Culicidae) with Piper aduncum L. (Piperaceae) extracts demonstrated by chromosomal biomarkers and toxic effects on interphase nuclei.

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Rafael, M S; Hereira-Rojas, W J; Roper, J J; Nunomura, S M; Tadei, W P

2008-01-01

Dillapiol, a phenylpropanoid isolate from essential oils of leaves of Piper aduncum (Piperaceae), has insecticidal, fungicidal and antimicrobial activities. The insecticidal activity of dillapiol was tested in vivo on the larvae and pupae of Aedes aegypti, the mosquito vector of dengue. Specifically, the effect of dillapiol on the formation of micronuclei and chromosome aberrations was analyzed. Dillapiol treatments comprised two concentrations of 200 and 400 micro dissolved in well water, and a pure well water control used to rear four generations of mosquitoes. Micronuclei occurred in mitotic diploid and tetraploid chromosomes of larvae; nuclear abnormalities also occurred in interphase, metaphase, telophase, and single nucleus cells of pupae. Mortality, oviposition, chromosome breakage, and anaphase bridges were significantly greater in the extract treatments than in controls. The genotoxic effects of dillapiol described here suggest that this natural product may be a useful alternative for the control of A. aegypti.

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

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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. © The Authors 2015. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Vertical Transmission of Zika Virus by Aedes aegypti and Ae. albopictus Mosquitoes.

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Ciota, Alexander T; Bialosuknia, Sean M; Ehrbar, Dylan J; Kramer, Laura D

2017-05-01

To determine the potential role of vertical transmission in Zika virus expansion, we evaluated larval pools of perorally infected Aedes aegypti and Ae. albopictus adult female mosquitoes; ≈1/84 larvae tested were Zika virus-positive; and rates varied among mosquito populations. Thus, vertical transmission may play a role in Zika virus spread and maintenance.

Development and applications of transgenesis in the yellow fever mosquito, Aedes aegypti.

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Adelman, Zachary N; Jasinskiene, Nijole; James, Anthony A

2002-04-30

Transgenesis technology has been developed for the yellow fever mosquito, Aedes aegypti. Successful integration of exogenous DNA into the germline of this mosquito has been achieved with the class II transposable elements, Hermes, mariner and piggyBac. A number of marker genes, including the cinnabar(+) gene of Drosophila melanogaster, and fluorescent protein genes, can be used to monitor the insertion of these elements. The availability of multiple elements and marker genes provides a powerful set of tools to investigate basic biological properties of this vector insect, as well as the materials for developing novel, genetics-based, control strategies for the transmission of disease.

Investigation of the Cry4B-prohibitin interaction in Aedes aegypti cells.

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Kuadkitkan, Atichat; Smith, Duncan R; Berry, Colin

2012-10-01

Bacillus thuringiensis (Bt) produces insecticidal toxins active against insects. Cry4B, one of the major insecticidal toxins produced by Bt subsp. israelensis, is highly toxic to mosquitoes in the genus Aedes: the major vectors of dengue, yellow fever, and chikungunya. Previous work has shown that Cry4B binds to several mid-gut membrane proteins in Aedes aegypti larvae including prohibitin, a protein recently identified as a receptor that also mediates entry of dengue virus into Aedes cells. This study confirms the interaction between Cry4B and prohibitin by co-immunoprecipitation analysis and demonstrates colocalization of prohibitin and Cry4B by confocal microscopy. While activated Cry4B toxin showed high larvicidal activity, it was not cytotoxic to two Aedes cell lines, allowing determination of its effect on dengue virus infectivity in the absence of Cry4B-induced cell lysis. Pre-exposure of Aedes cells to Cry4B resulted in a significant reduction in the number of infected cells compared to untreated cells.

Efikasi Ekstrak Daun dan Bunga Kecombrang (Etlingera elatior terhadap Larva Aedes aegypti

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Meiske Elisabeth Koraag

2016-12-01

Full Text Available Abstract. Three widely known dengue vector control programs in Indonesia are chemical, biological, and environmental modification control where chemical control with organophosphate insecticide (malathion and temephos is the most common. The long term use of chemical insecticide will result in the vector beingtolerant and eventually resistant to insecticide. One of the alternative solutions is to use biological larvacide from the plant. The objective of this study was to determine the lethal concentration of the extract of Kecombrang (Etlingera elatior leaves and flowers against Aedes aegypti larvae. This was an experimentalstudy where the sample size was determined by using the Federer formula. The study used six different concentrations and four repetitions. Two controls group, Bacillus thuringiensis and water used as positive and negative control. The results showed that the LC50 and LC90 of Kecombrang leave extract were 1.20% and 2.05% respectively whereas for Kecombrang flowers extract were 0,05% and 0.09% respectively. Extract of Kecombrang leaves and flowers is effective to kill Ae. aegypti larvae where the flowers extract is more effective than the leaves extract in killing Ae. aegypti larvae.Keywords: dengue, Ae. aegypti, larvae, Etlingera elatiorAbstrak. Pengendalian vektor penular demam berdarah dengue (DBD yang selama ini dikenal yaitu pengendalian secara kimia, biologi dan modifikasi lingkungan. Pengendalian vektor DBD di Indonesia masih banyak dilakukan dengan menggunakan insektisida dari golongan organofosfat (malation dan temefos. Penggunaan insektisida kimia dalam jangka waktu lama akan memberi efek menekan dan menyeleksi serangga vektor sasaran untuk menjadi toleran sampai resisten. Salah satu solusi alternatif yaitu menggunakan larvasida yang berasal dari tanaman. Penelitian ini bertujuan untuk menentukan daya bunuh ekstrak daun dan bunga kecombrang (Etlingera elatior terhadap larva nyamuk Ae. aegypti. Jenis penelitian yang

Genome-based polymorphic microsatellite development and validation in the mosquito Aedes aegypti and application to population genetics in Haiti

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Streit Thomas G

2009-12-01

Full Text Available Abstract Background Microsatellite markers have proven useful in genetic studies in many organisms, yet microsatellite-based studies of the dengue and yellow fever vector mosquito Aedes aegypti have been limited by the number of assayable and polymorphic loci available, despite multiple independent efforts to identify them. Here we present strategies for efficient identification and development of useful microsatellites with broad coverage across the Aedes aegypti genome, development of multiplex-ready PCR groups of microsatellite loci, and validation of their utility for population analysis with field collections from Haiti. Results From 79 putative microsatellite loci representing 31 motifs identified in 42 whole genome sequence supercontig assemblies in the Aedes aegypti genome, 33 microsatellites providing genome-wide coverage amplified as single copy sequences in four lab strains, with a range of 2-6 alleles per locus. The tri-nucleotide motifs represented the majority (51% of the polymorphic single copy loci, and none of these was located within a putative open reading frame. Seven groups of 4-5 microsatellite loci each were developed for multiplex-ready PCR. Four multiplex-ready groups were used to investigate population genetics of Aedes aegypti populations sampled in Haiti. Of the 23 loci represented in these groups, 20 were polymorphic with a range of 3-24 alleles per locus (mean = 8.75. Allelic polymorphic information content varied from 0.171 to 0.867 (mean = 0.545. Most loci met Hardy-Weinberg expectations across populations and pairwise FST comparisons identified significant genetic differentiation between some populations. No evidence for genetic isolation by distance was observed. Conclusion Despite limited success in previous reports, we demonstrate that the Aedes aegypti genome is well-populated with single copy, polymorphic microsatellite loci that can be uncovered using the strategy developed here for rapid and efficient

Host-feeding pattern of Aedes aegypti and Aedes albopictus (Diptera: Culicidae) in heterogeneous landscapes of South Andaman, Andaman and Nicobar Islands, India.

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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.

Multiple introductions of the dengue vector, Aedes aegypti, into California.

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Pless, Evlyn; Gloria-Soria, Andrea; Evans, Benjamin R; Kramer, Vicki; Bolling, Bethany G; Tabachnick, Walter J; Powell, Jeffrey R

2017-08-01

The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA) in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a) examining additional Northern CA samples and including samples from Southern CA, (b) including more southern US populations for comparison, and (c) genotyping a subset of samples at 15,698 SNPs. Major results are: (1) Northern and Southern CA populations are distinct. (2) Northern populations are more genetically diverse than Southern CA populations. (3) Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4) Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5) A Northern CA population analyzed at multiple time-points (two years apart) is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding.

Multiple introductions of the dengue vector, Aedes aegypti, into California.

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Evlyn Pless

2017-08-01

Full Text Available The yellow fever mosquito Aedes aegypti inhabits much of the tropical and subtropical world and is a primary vector of dengue, Zika, and chikungunya viruses. Breeding populations of A. aegypti were first reported in California (CA in 2013. Initial genetic analyses using 12 microsatellites on collections from Northern CA in 2013 indicated the South Central US region as the likely source of the introduction. We expanded genetic analyses of CA A. aegypti by: (a examining additional Northern CA samples and including samples from Southern CA, (b including more southern US populations for comparison, and (c genotyping a subset of samples at 15,698 SNPs. Major results are: (1 Northern and Southern CA populations are distinct. (2 Northern populations are more genetically diverse than Southern CA populations. (3 Northern and Southern CA groups were likely founded by two independent introductions which came from the South Central US and Southwest US/northern Mexico regions respectively. (4 Our genetic data suggest that the founding events giving rise to the Northern CA and Southern CA populations likely occurred before the populations were first recognized in 2013 and 2014, respectively. (5 A Northern CA population analyzed at multiple time-points (two years apart is genetically stable, consistent with permanent in situ breeding. These results expand previous work on the origin of California A. aegypti with the novel finding that this species entered California on multiple occasions, likely some years before its initial detection. This work has implications for mosquito surveillance and vector control activities not only in California but also in other regions where the distribution of this invasive mosquito is expanding.

PENGGUNAAN EKSTRAK KULIT KAYU GEMOR (Nothaphoebe coriacea K. SEBAGAI LARVASIDA HAYATI TERHADAP TINGKAT MORTALITAS JENTIK NYAMUK Aedes aegypti SERTA DAMPAKNYA PADA KUALITAS AIR HUJAN

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Pranata Dyah Susanti

2016-10-01

Full Text Available Gemor plants (Nothaphoebe coriacea K. is the producer of one type of mainstay NTFP (Non-Timber Forest Products in Kalimantan. Bark of gemor is potential to be used as a biological larvacide, especially against Aedes aegypti larvae which are the carriers of disease vectors of Dengue Hemorrhagic Fever (DHF. This study aimed to analyze the effect of bark extract concentration of gemor as a biological larvacide against: (1 the mortality rate of Aedes aegypti mosquito larvae, and (2 the physical and chemical quality of rainwater. The research method used was a completely randomized design (CRD with 6 treatments and 5 replications. Treatment applied in this research was gemor bark extract concentration, namely: L0 (0 ppm, L1 (400 ppm, L2 (800 ppm, L3 (1,200 ppm, L4 (1,600 ppm, and L5 (2,000 ppm. Larvae used in this study were Aedes aegypti larvae in the third instar. The variables observed were the mortality rate of Aedes aegypti mosquito larvae and the rain water quality parameters, including pH and TDS. The results indicated that increasing concentrations of gemor bark extract significantly (p <0.05 increase the mortality rate of Aedes aegypti larvae. During 12 hours of observation, the percentage of larvae mortality at a concentration of 400 ppm (L1 was 42% and increased to 100% at a concentration of 2,000 ppm (L5, whereas in the control (L0 no  mortality was observed. Gemor bark extract may improve the rainwater pH between 0.02 to 0.04. TDS parameter value for the L0 treatment was 4 mg / l, while for the L1 it was 37.6 mg / l and increased to 806.2 mg / l for the L5 . Nonetheless, the value of TDS in the L5 concentration still meets the standards of Ministry of Health Decree No. 416/MENKES/PER/IX/1990 about the Terms and Water Quality Monitoring.

PENGARUH BEBERAPA DOSIS BACILLUS THURINGIENSIS VAR ISRAELENSIS SEROTYPE H14 TERHADAP LARVA AEDES AEGYPTI DI KALIMANTAN BARAT

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Dian Perwitasari

2016-03-01

Full Text Available One of the dengue control efforts is the use  of Bacillus thuringiensis in order to reduce the dengue vector of Aedes aegypti through its larvas. This was an experimental research using gram-positive bacteria B. thuringiensis var israelensis (Bactivec serotype H-14 which was applied with several concentrations (0.02 ml, 0.01 ml and 0.007 ml in 246 ml of water that has been filled with 25 larvas of the 3rd or 4th instars. Larvas were taken from the area of ​​West Kalimantan. Data were analyzed using a completely randomized design to examine the percentage of larval mortality within 3 hours, 9 hours and over 12 hours. The results showed that the concentration of 0,02 bactivec caused 89%  larval mortality, and  concentrations of 0,01 and 0,007 caused 88% and 87% larval mortality, respectively within the 9 hours exposure time. It can be concluded that the use of 0,07 ml of bactivec  is still effective to  control  Aedes aegypti larvae. To determine  the negative of  the use of bactivec,  further studies  are needed.  

Insecticide Resistance in the Dengue Vector Aedes aegypti from Martinique: Distribution, Mechanisms and Relations with Environmental Factors

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Marcombe , Sébastien; Blanc Mathieu , Romain; Pocquet , Nicolas; Riaz , Muhammad-Asam; Poupardin , Rodolphe; Sélior , Serge; Darriet , Frédéric; Reynaud , Stéphane; Yebakima , André; Corbel , Vincent; David , Jean-Philippe; Chandre , Fabrice

2012-01-01

International audience; Dengue is an important mosquito borne viral disease in Martinique Island (French West Indies). The viruses responsible for dengue are transmitted by Aedes aegypti, an indoor day-biting mosquito. The most effective proven method for disease prevention has been by vector control by various chemical or biological means. Unfortunately insecticide resistance has already been observed on the Island and recently showed to significantly reduce the efficacy of vector control in...

Trial of Neem Oil (Azadirachta Indica) as Basic Compound of Electric Liquid Vaporizer Against Aedes Aegypti Mortality

OpenAIRE

Diptyanusa, Ajib; Satoto, Tri Baskoro Tunggul; Hadianto, Tridjoko

2017-01-01

Dengue Hemorrhagic Fever (DHF), commonly caused by Aedes aegypti mosquito bites, has been one of the worlds major concern for progressively increasing incidence. To prevent further increase in DHF incidence, an effective yet safe vector control method is needed. One of the most common method of vector control in Indonesia is using electric liquid vaporizer. Basic compounds which are less toxic to humans and less resistance-producing to mosquitoes are preferred, without neglecting its ability ...

Germline excision of transgenes in Aedes aegypti by homing endonucleases.

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Aryan, Azadeh; Anderson, Michelle A E; Myles, Kevin M; Adelman, Zach N

2013-01-01

Aedes (Ae.) aegypti is the primary vector for dengue viruses (serotypes1-4) and chikungunya virus. Homing endonucleases (HEs) are ancient selfish elements that catalyze double-stranded DNA breaks (DSB) in a highly specific manner. In this report, we show that the HEs Y2-I-AniI, I-CreI and I-SceI are all capable of catalyzing the excision of genomic segments from the Ae. aegypti genome in a heritable manner. Y2-I-AniI demonstrated the highest efficiency at two independent genomic targets, with 20-40% of Y2-I-AniI-treated individuals producing offspring that had lost the target transgene. HE-induced DSBs were found to be repaired via the single-strand annealing (SSA) and non-homologous end-joining (NHEJ) pathways in a manner dependent on the availability of direct repeat sequences in the transgene. These results support the development of HE-based gene editing and gene drive strategies in Ae. aegypti, and confirm the utility of HEs in the manipulation and modification of transgenes in this important vector.

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

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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 ...

Spatial repellency screening in a high-throughput apparatus with Aedes aegypti and Anopheles gambiae

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Spatial repellents are essential for personal protection against mosquitoes, such as Aedes aegypti and Anopheles gambiae, to reduce annoyance biting and transmission of mosquito-borne diseases. The number of safe and effective repellents, including DEET, picaridin, and IR3535, is limited and contin...

Wolbachia infection in Aedes aegypti mosquitoes alters blood meal excretion and delays oviposition without affecting trypsin activity.

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Pimenta de Oliveira, Sofia; Dantas de Oliveira, Caroline; Viana Sant'Anna, Mauricio Roberto; Carneiro Dutra, Heverton Leandro; Caragata, Eric Pearce; Moreira, Luciano Andrade

2017-08-01

Blood feeding in Aedes aegypti is essential for reproduction, but also permits the mosquito to act as a vector for key human pathogens such as the Zika and dengue viruses. Wolbachia pipientis is an endosymbiotic bacterium that can manipulate the biology of Aedes aegypti mosquitoes, making them less competent hosts for many pathogens. Yet while Wolbachia affects other aspects of host physiology, it is unclear whether it influences physiological processes associated with blood meal digestion. To that end, we examined the effects of wMel Wolbachia infection in Ae. aegypti, on survival post-blood feeding, blood meal excretion, rate of oviposition, expression levels of key genes involved in oogenesis, and activity levels of trypsin blood digestion enzymes. We observed that wMel infection altered the rate and duration of blood meal excretion, delayed the onset of oviposition and was associated with a greater number of eggs being laid later. wMel-infected Ae. aegypti also had lower levels of key yolk protein precursor genes necessary for oogenesis. However, all of these effects occurred without a change in trypsin activity. These results suggest that Wolbachia infection may disrupt normal metabolic processes associated with blood feeding and reproduction in Ae. aegypti. Copyright © 2017 Elsevier Ltd. All rights reserved.

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

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Seixas, Gonçalo; Salgueiro, Patrícia; Silva, Ana Clara; Campos, Melina; Spenassatto, Carine; Reyes-Lugo, Matías; Novo, Maria Teresa; Ribolla, Paulo Eduardo Martins; Silva Pinto, João Pedro Soares da; Sousa, Carla Alexandra

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 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.

Ecología del Aedes aegypti en un pueblo de Colombia, Suramérica

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Milton E. Tinker

1993-03-01

Full Text Available Un estudio de la ecología de las larvas y adultos del Aedes aegypti fue llevado a cabo en Guaduas (Cundinamarca entre noviembre de 1978 y noviembre de 1979. Este estudio comprendió cuatro ciclos de inspección, dos en época seca y dos en época lluviosa. Las albercas fueron encontradas como el mejor hábitat larvario para ambas estaciones. Las llantas fueron igualmente importantes en la época de lluvia. Las alcobas constituyeron el hábitat más favorable para los adultos. En general más predios estaban infestados por adultos que por larvas. La prueba de las precipitinas indicó que la mayoría de las hembras de Aedes aegypti se alimentaron sobre el hombre. Las colecciones con cebo humano demostraron 2 picos de actividad: 10 -1 1 a.m. y 4-5 p.m.

Potential use of Piper nigrum ethanol extract against pyrethroid-resistant Aedes aegypti larvae Utilização em potencial do extrato alcoólico de Piper nigrum como larvicida em Aedes aegypti resistente a piretróides

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Naomi Kato Simas

2007-08-01

Full Text Available Fractionation of Piper nigrum ethanol extract, biomonitored by assays on pyrethroid-resistant Aedes aegypti larvae yielded isolation of the larvicidal amides piperolein-A and piperine. Comparing LC50 values, the ethanol extract (0. 98 ppm was the most toxic, followed by piperolein-A (1. 46ppm and piperine (1. 53ppm.O fracionamento do extrato etanólico de Piper nigrum biomonitorado por ensaios em larvas de Aedes aegypti resistentes a piretróides resultou no isolamento das amidas larvicidas piperoleína-A e piperina. Comparando-se os valores de CL50, o extrato etanólico (0. 98ppm foi o mais tóxico, seguido pela piperoleína-A (1. 46ppm e piperina (1. 53ppm.

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

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Manda, Hortance; Shah, Pankhil; Polsomboon, Suppaluck; Chareonviriyaphap, Theeraphap; Castro-Llanos, Fanny; Morrison, Amy; Burrus, Roxanne G; Grieco, John P; Achee, Nicole L

2013-01-01

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. 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. 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 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%. 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 currently unknown and will depend on rate of biting on human hosts prior to house exiting.

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

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Hasan Boesri

2013-02-01

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

Similarity solutions for systems arising from an Aedes aegypti model

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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.

AEGY-28 Cell Line of Aedes aegypti (Diptera Culicidae is Infection Refractory to Dengue 2 and Yellow Fever Virus

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Nadia Y. Castañeda

2007-07-01

Full Text Available Mosquito cell derived cultures are useful tools for arbovirus isolation, identification or characterization. For studying dengue (DENV and yellow fever viruses (YFV Aedes albopictus C6/36 or Aedes pseudoscutellaris AP-61 cell lines, are normally used. The Aedes aegypti AEGY-28 cell line was obtained from embryonic tissues and characterized previously by one of us. In order to evaluate its susceptibility to two Flavivirus, AEGY- 28 cells were inoculated with different multiplicity of infection (MOI with type 2 DENV (COL-789, MOI: 1 and 5 and YFV clinical isolates (V-341, MOI 0,02 then processed at different times post infection (p.i.. Immunostai ning and fluorometric cell-ELISA were carried out to identify and quantify viral antigens. C6/36 and Vero cells were used as positive controls. Unexpectedly, immunoreactivity was not found in inoculated AEGY-28 cells, even in higher MOI or late times p.i., therefore antigen quantification using fluorometric cell-ELISA were not  plausible. Reverse transcriptase PCR with specific primers did not detect viral RNA in AEGY-28 inoculated cells. We can conclude that Aedes aegypti AEGY-28 cell line is not susceptible to dengue and yellow fever Flavivirus, a finding possibly related with the lacking of specific molecules at the plasma membrane or absence of cell machinery necessary for viral replication.

Development of a Low Cost Bioprocess for Endotoxin Production by Bacillus thuringiensis var israelensis Intended for Biological Control of Aedes aegypti

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Carlos Ricardo Soccol

2009-11-01

Full Text Available Aedes aegypti is the vector of Dengue disease, responsible for 20,000 deaths/year worldwide. Bacillus thuringiensis var israelensis - Bti releases selective and effective toxins (crystal proteins against A. aegypti larvae. We present a low cost bioprocess for toxin production, accomplished by a selected Brazilian strain Bti (BR-LPB01 and employment of low cost substrates. Soybean meal and sugarcane molasses lead to high toxic effectiveness after 2L bioreactor fermentation (LD50=26ng/mL, near to the reference strain IPS82 (LD50=17.3 ng/mL. The pH ranged between 5.8 and 7.0 during the exponential growth period and between 7.0 and 8.4 during the stationary phase, with low activity. Thus, control of foam and pH 7.0 were started and proved to be crucial for high activity. It was verified that the fermentation could be discontinued after 20 hours, when the highest activity was present.A dengue é transmitida pelo Aedes aegypti, doença responsável por 20.000 mortes/ano no mundo. Bacillus thuringiensis var israelensis libera toxinas seletivas e eficazes (proteínas cristal contra larvas de A. aegypti. Propõe-se um bioprocesso de baixo custo para a produção da toxina, pelo emprego de uma cepa brasileira selecionada de Bti (BR-LPB01 e de substratos de baixo custo. Farelo de soja e melaço de cana levaram a eficácia tóxica alta após fermentação em biorreator 2L (DL50=26ng/mL, valor próximo a estirpe de referência IPS82 (DL50=17,3 ng/mL. O pH variou entre 5,8 e 7,0 durante o período de crescimento exponencial e entre 7,0 e 8,4 durante a fase estacionária, com baixa atividade larvicida. Assim, controles de espuma e de pH 7,0 foram iniciados e demonstraram serem cruciais para alta atividade. Verificou-se que a fermentação deve ser interrompida após vinte horas, quando se obtém a maior atividade.

Behavioral Response of Aedes aegypti Mosquito towards Essential Oils Using Olfactometer

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

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 in laboratory conditions using Y-tube olfactometer. Results: The essential oils exhibited varying degree of repellency. Litsea oil showed 50.31%, 60.2 %, and 77.26% effective mean repellency at 1 ppm, 10 ppm and 100 ppm respectively, while DEET exhibited 59.63%, 68.63%, 85.48% and DEPA showed 57.97%, 65.43%, and 80.62% repellency at respective above concentrations. Statistical analysis revealed that among the tested essential oils, litsea oil had effective repellency in comparison with DEET and DEPA against Ae. aegypti mosquito at all concentration. Essential oils, DEET and DEPA showed significant repellence against Ae. aegypti (Poil exhibited effective percentage repellency similar to DEET and DEPA. The essential oils are natural plant products that may be useful for developing safer and newer herbal based effective mosquito repellents. PMID:27308295

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

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

2015-09-01

The mosquito Stegomyia aegypti (=Aedes aegypti) (Diptera: Culicidae) is a vector for the dengue and yellow fever viruses. As blood digestion occurs in the midgut, this organ constitutes the route of entry of many pathogens. The effects of the insecticide imidacloprid on the survival of St. aegypti were investigated and the sub-lethal effects of the insecticide on midgut development were determined. Third instar larvae were exposed to different concentrations of imidacloprid (0.15, 1.5, 3.0, 6.0 and 15.0 p.p.m.) and survival was monitored every 24 h for 10 days. Midguts from imidacloprid-treated insects at different stages of development were dissected and processed for analyses by transmission electron microscopy, immunofluorescence microscopy and terminal deoxynucleotidyl transferase dUTP nick-end labelling (TUNEL) assays. Imidacloprid concentrations of 3.0 and 15.0 p.p.m. were found to affect midgut development similarly. Digestive cells of the fourth instar larvae (L4) midgut exposed to imidacloprid had more multilamellar bodies, abundantly found in the cell apex, and more electron-lucent vacuoles in the basal region compared with those from untreated insects. Moreover, imidacloprid interfered with the differentiation of regenerative cells, dramatically reducing the number of digestive and endocrine cells and leading to malformation of the midgut epithelium in adults. The data demonstrate that imidacloprid can reduce the survival of mosquitoes and thus indicate its potentially high efficacy in the control of St. aegypti populations. © 2015 The Royal Entomological Society.

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

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

2012-01-01

México has cities (e.g., México City and Puebla City) located at elevations > 2,000 m and above the elevation ceiling below which local climates allow the dengue virus mosquito vector Aedes aegypti to proliferate. Climate warming could raise this ceiling and place high-elevation cities at risk for dengue virus transmission. To assess the elevation ceiling for Ae. aegypti and determine the potential for using weather/climate parameters to predict mosquito abundance, we surveyed 12 communities along an elevation/climate gradient from Veracruz City (sea level) to Puebla City (∼2,100 m). Ae. aegypti was commonly encountered up to 1,700 m and present but rare from 1,700 to 2,130 m. This finding extends the known elevation range in México by > 300 m. Mosquito abundance was correlated with weather parameters, including temperature indices. Potential larval development sites were abundant in Puebla City and other high-elevation communities, suggesting that Ae. aegypti could proliferate should the climate become warmer. PMID:22987656

Effects of desiccation stress on adult female longevity in Aedes aegypti and Ae. albopictus (Diptera: Culicidae): results of a systematic review and pooled survival analysis.

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Schmidt, Chris A; Comeau, Genevieve; Monaghan, Andrew J; Williamson, Daniel J; Ernst, Kacey C

2018-04-25

. Humidity is associated with mortality risk in adult female Ae. aegypti in controlled settings. Data are limited at low humidities, temperature extremes, and for Ae. albopictus, and further studies should be conducted to reduce model uncertainty in these contexts. Desiccation is likely an important factor in Aedes population dynamics and viral transmission in arid regions. Models of Aedes-borne virus transmission may be improved by more comprehensively representing humidity effects.

Comparative Efficacy of Commercial Mosquito Coils Against Aedes aegypti (Diptera: Culicidae) in Malaysia: A Nationwide Report.

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Chin, A C; Chen, C D; Low, V L; Lee, H L; Azidah, A A; Lau, K W; Sofian-Azirun, M

2017-10-01

This study was conducted using the glass chamber method to determine the susceptibility status of the dengue vector, Aedes aegypti (L.) from 11 states in Malaysia to commercial mosquito coils containing four different active ingredients, namely metofluthrin, d-allethrin, d-trans allethrin, and prallethrin. Aedes aegypti exhibited various knockdown rates, ranging from 14.44% to 100.00%, 0.00% to 61.67%, 0.00% to 90.00%, and 0.00% to 13.33% for metofluthrin, d-allethrin, d-trans allethrin, and prallethrin, respectively. Overall, mortality rates ranging from 0.00% to 78.33% were also observed among all populations. Additionally, significant associations were detected between the knockdown rates of metofluthrin and d-allethrin, and between metofluthrin and d-trans allethrin, suggesting the occurrence of cross-resistance within pyrethroid insecticides. Overall, this study revealed low insecticidal activity of mosquito coils against Ae. aegypti populations in Malaysia, and consequently may provide minimal personal protection against mosquito bites. © The Author 2017. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Proof of concept for a novel insecticide bioassay based on sugar feeding by adult Aedes aegypti (Stegomyia aegypti).

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Stell, F M; Roe, R M; Arellano, C; Kennedy, L; Thornton, H; Saavedra-Rodriguez, K; Wesson, D M; Black, W C; Apperson, C S

2013-09-01

Aedes aegypti L. (Stegomyia aegypti) (Diptera: Culicidae) is the principal vector of dengue and yellow fever viruses in tropical and subtropical regions of the world. Disease management is largely based on mosquito control achieved by insecticides applied to interior resting surfaces and through space sprays. Population monitoring to detect insecticide resistance is a significant component of integrated disease management programmes. We developed a bioassay method for assessing insecticide susceptibility based on the feeding activity of mosquitoes on plant sugars. Our prototype sugar-insecticide feeding bioassay system was composed of inexpensive, disposable components, contained minimal volumes of insecticide, and was compact and highly transportable. Individual mosquitoes were assayed in a plastic cup that contained a sucrose-permethrin solution. Trypan blue dye was added to create a visual marker in the mosquito's abdomen for ingested sucrose-permethrin solution. Blue faecal spots provided further evidence of solution ingestion. With the sugar-insecticide feeding bioassay, the permethrin susceptibility of Ae. aegypti females from two field-collected strains was characterized by probit analysis of dosage-response data. The field strains were also tested by forced contact of females with permethrin residues on filter paper. Dosage-response patterns were similar, indicating that the sugar-insecticide feeding bioassay had appropriately characterized the permethrin susceptibility of the two strains. © 2012 The Royal Entomological Society.

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

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

2015-12-01

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

Perbedaan respon Aedes aegypti (Linnaeus) (Diptera: Culicidae), terhadap paparan anti nyamuk bakar dan bunga keluwih (Artocarpus camansi, Blanco)

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Nur Endah Wahyuningsih; Ramauli Agustina Sihit

2015-01-01

The control of dengue hemorrhagic fever (DHF) it is important to control the vector, i.e. Aedes aegypti (Linnaeus) and Ae. albopictus (Skuse). Usually, controls of these vectors are done using chemical insecticides. Research on mosquito resistance has been done, but the impact of mosquitoes that survive after synthetic (chemical) insecticides application has not been studied. The aim of this research was to analyze the differences of fecundity, fertility and vitality rate of mosquitoes that w...

Susceptibilidad de Aedes aegypti a DDT, deltametrina y lambdacialotrina en Colombia Susceptibility of Aedes aegypti to DDT, deltamethrin, and lambda-cyhalothrin in Colombia

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Liliana Santacoloma Varón

2010-01-01

Full Text Available OBJETIVOS: Evaluar el estado de susceptibilidad a insecticidas piretroides deltametrina y lambdacialotrina y al organoclorado DDT, e identificar los mecanismos bioquímicos asociados con resistencia en 13 poblaciones naturales de Aedes aegypti recolectadas en localidades de Colombia donde el dengue es un grave problema de salud pública. MÉTODOS: Se recolectaron y criaron en condiciones controladas formas inmaduras de diferentes criaderos naturales del vector para cada localidad. Con la generación F2 se realizaron bioensayos utilizando las metodologías OMS 1981 (papeles impregnados y CDC 1998 (botellas impregnadas. En las poblaciones con mortalidades compatibles con disminución de la susceptibilidad, se midieron los niveles de esterasas no específicas (ENE, oxidasas de función mixta (OFM y acetilcolinesterasa modificada (ACEM mediante pruebas colorimétricas. RESULTADOS: Todas las poblaciones del mosquito evaluadas evidenciaron resistencia al organoclorado DDT. En cuanto a los piretroides, se encontró resistencia generalizada a lambdacialotrina pero no a deltametrina. Los mecanismos bioquímicos de resistencia evaluados permitieron encontrar 7 de 11 poblaciones con ENE elevadas y una población con OFM incrementadas. CONCLUSIONES: Se descarta la resistencia cruzada de tipo fisiológico entre el DDT y lambdacialotrina en las poblaciones de A. aegypti evaluadas. La resistencia fisiológica a lambdacialotrina parece asociarse con el incremento de las ENE. El comportamiento diferencial en los niveles de susceptibilidad y los valores enzimáticos entre poblaciones se asociaron con la variabilidad genética y presión de selección química a nivel local.OBJECTIVES: To assess the susceptibility status of 13 natural populations of Aedes aegypti (collected from sites in Colombia where dengue is a serious public health problem to the pyrethroids, deltamethrin and lambda-cyhalothrin, and to the organochlorine, DDT, and to identify any biochemical

Screening of plants found in the State of Amazonas, Brazil for activity against Aedes aegypti larvae Triagem de plantas encontradas no Estado do Amazonas para atividade larvicida contra Aedes aegypti

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Adrian Martin Pohlit

2004-01-01

Full Text Available Ethanol, methanol and water extracts representing mostly native plant species found in the Amazon region were prepared, respectively, by maceration, continuous liquid-solid extraction and infusion, followed by evaporation and freeze-drying. The freeze-dried extracts were tested for lethality toward Aedes aegypti larvae at test concentrations of 500 mg / mL. In general, methanol extracts exhibited the greatest larvicidal activity. The following 7 methanol extracts of (the parts of the indicated plant species were the most active, resulting in 100% mortality in A. aegypti larvae: Tapura amazonica Poepp. (root, Piper aduncum L. (leaf and root, P. tuberculatum Jacq. (leaf, fruit and branch. and Simaba polyphylla (Cavalcante W.W. Thomas (branch.Extratos aquosos, etanólicos e metanólicos, representando principalmente espécies vegetais nativas encontradas na região Amazônica, foram preparados, respectivamente, por infusão, maceração e extração contínua líquido-sólido, seguida de evaporação e liofilização. Os extratos liofilizados foram testados para atividade contra larvas de Aedes aegypti, na concentração única de 500 mg / mL. Os extratos metanólicos foram, em geral, os que apresentaram maior atividade larvicida. Os seguintes 7 extratos metanólicos das (partes das espécies vegetais indicadas foram os mais ativos, provocando 100% de mortalidade em larvas de A. aegypti: Tapura amazonica Poepp. (raiz, Piper aduncum L. (folha e raiz, P. tuberculatum Jacq. (folha, fruto e galho e Simaba polyphylla (Cavalcante W.W. Thomas (galho.

Evaluation of Alternative Killing Agents for Aedes aegypti (Diptera: Culicidae) in the Gravid Aedes Trap (GAT).

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Heringer, Laila; Johnson, Brian J; Fikrig, Kara; Oliveira, Bruna A; Silva, Richard D; Townsend, Michael; Barrera, Roberto; Eiras, Álvaro E; Ritchie, Scott A

2016-07-01

The Gravid Aedes Trap (GAT) uses visual and olfactory cues to attract gravid Aedes aegypti (L.) that are then captured when knocked down by a residual pyrethroid surface spray. However, the use of surface sprays can be compromised by poor availability of the spray and pesticide resistance in the target mosquito. We investigated several "alternative" insecticide and insecticide-free killing agents for use in the GAT. This included long-lasting insecticide-impregnated nets (LLINs), vapor-active synthetic pyrethroids (metofluthrin), canola oil, and two types of dry adhesive sticky card. During bench top assays LLINs, metofluthrin, and dry sticky cards had 24-h knockdown (KD) percentages >80% (91.2 ± 7.2%, 84.2 ± 6.8%, and 83.4 ± 6.1%, respectively), whereas the 24-h KD for canola oil was 70 ± 7.7%, which improved to 90.0 ± 3.7% over 48 h. Importantly, there were no significant differences in the number of Ae. aegypti collected per week or the number of traps positive for Ae. aegypti between the sticky card and canola oil treatments compared with the surface spray and LLIN treatments in semifield and field trials. These results demonstrate that the use of inexpensive and widely available insecticide-free agents such as those described in this study are effective alternatives to pyrethroids in regions with insecticide-resistant populations. The use of such environmentally friendly insecticide-free alternatives will also be attractive in areas where there is substantial resistance to insecticide use due to environmental and public health concerns. © The Authors 2016. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For Permissions, please email: journals.permissions@oup.com.

Larvicidal activity of some Cerrado plant extracts against Aedes aegypti

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Rodrigues, A.M.S.; De Paula, J.E.; Dégallier, Nicolas; Molez, Jean-François; Espindola, L.S.

2006-01-01

One hundred ninety hexanic and ethanolic extracts from 27 plant species from the Cerrado biome of Brazil were tested for larvicidal activity against 3rd-stage Aedes aegypti larvae at 500 mu g/ml. Fourteen extracts from 7 species showed activity (> 65% mortality) against the larvae. Of these, Duguetia furfuracea, Piptocarpha rotundifolia, Casearia sylvestris var. lingua, Serjania lethalis, and Xylopia aromatica were active at 56.6, 162.31, 232.4, 285.76, and 384.37 mu g/ml, respectively. Annon...

Human Antibody Response to Aedes aegypti Saliva in an Urban Population in Bolivia: A New Biomarker of Exposure to Dengue Vector Bites

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Doucoure, Souleymane; Mouchet, François; Cournil, Amandine; Le Goff, Gilbert; Cornelie, Sylvie; Roca, Yelin; Giraldez, Mabel Guerra; Simon, Zaira Barja; Loayza, Roxanna; Misse, Dorothée; Flores, Jorge Vargas; Walter, Annie; Rogier, Christophe; Herve, Jean Pierre; Remoue, Franck

2012-01-01

Aedes mosquitoes are important vectors of re-emerging diseases in developing countries, and increasing exposure to Aedes in the developed world is currently a source of concern. Given the limitations of current entomologic methods, there is a need for a new effective way for evaluating Aedes exposure. Our objective was to evaluate specific antibody responses to Aedes aegypti saliva as a biomarker for vector exposure in a dengue-endemic urban area. IgG responses to saliva were strong in young children and steadily waned with age. Specific IgG levels were significantly higher in persons living in sites with higher Ae. aegypti density, as measured by using entomologic parameters. Logistic regression showed a significant correlation between IgG to saliva and exposure level, independently of either age or sex. These results suggest that antibody responses to saliva could be used to monitor human exposure to Aedes bites. PMID:22848099

Temporal Dynamics and Spatial Patterns of Aedes aegypti Breeding Sites, in the Context of a Dengue Control Program in Tartagal (Salta Province, Argentina)

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Espinosa, Manuel; Weinberg, Diego; Rotela, Camilo H.; Polop, Francisco; Abril, Marcelo; Scavuzzo, Carlos Marcelo

2016-01-01

Background Since 2009, Fundación Mundo Sano has implemented an Aedes aegypti Surveillance and Control Program in Tartagal city (Salta Province, Argentina). The purpose of this study was to analyze temporal dynamics of Ae. aegypti breeding sites spatial distribution, during five years of samplings, and the effect of control actions over vector population dynamics. Methodology/Principal Findings Seasonal entomological (larval) samplings were conducted in 17,815 fixed sites in Tartagal urban area between 2009 and 2014. Based on information of breeding sites abundance, from satellite remote sensing data (RS), and by the use of Geographic Information Systems (GIS), spatial analysis (hotspots and cluster analysis) and predictive model (MaxEnt) were performed. Spatial analysis showed a distribution pattern with the highest breeding densities registered in city outskirts. The model indicated that 75% of Ae. aegypti distribution is explained by 3 variables: bare soil coverage percentage (44.9%), urbanization coverage percentage(13.5%) and water distribution (11.6%). Conclusions/Significance This results have called attention to the way entomological field data and information from geospatial origin (RS/GIS) are used to infer scenarios which could then be applied in epidemiological surveillance programs and in the determination of dengue control strategies. Predictive maps development constructed with Ae. aegypti systematic spatiotemporal data, in Tartagal city, would allow public health workers to identify and target high-risk areas with appropriate and timely control measures. These tools could help decision-makers to improve health system responses and preventive measures related to vector control. PMID:27223693

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

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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 < 2.3). Biochemical tests performed with larvae and adults discarded the participation of acetylcholinesterase, the OP target, and confirmed involvement of the detoxifying enzymes esterases, mixed function oxidases, and glutathione-S-transferases. The results obtained were discussed taking into account the public chemical control component and the increase in the domestic use of insecticides during dengue epidemic seasons in the evaluated municipalities. PMID:27419140

Productive container types for Aedes aegypti immatures in Mérida, México.

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García-Rejón, Julian E; López-Uribe, Mildred P; Loroño-Pino, María Alba; Farfán-Ale, José Arturo; Del Najera-Vazquez, Maria Rosario; Lozano-Fuentes, Saul; Beaty, Barry J; Eisen, Lars

2011-05-01

During 2007-2010, we examined which container types in Mérida, México, are most productive for Aedes aegypti (L.) immatures. Surveys for mosquito immatures followed routine surveillance methodology and container type classifications used by Servicios de Salud de Yucatán. Our main findings were that (1) small and larger discarded containers that serve no particular purpose and therefore can be removed from the environment contribute strongly to larval and pupal production in Mérida, and (2) the importance of different container types can vary among sets of residential premises as well as between dry and wet periods. These results may help to guide future implementation in Mérida of control efforts that target the most productive container types for Ae. aegypti immatures. Furthermore, if the Patio Limpio cleanup campaign that currently is ongoing in Mérida proves successful in removing discarded containers as important immature development sites, then we should see dramatic changes in the most productive container types in the future as the mosquito is forced to switch to other container types, which perhaps also will be easier to include in highly targeted mosquito control interventions.

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

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Vaea Richard

2016-05-01

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

First record of natural vertical transmission of dengue virus in Aedes aegypti from Cuba.

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Gutiérrez-Bugallo, Gladys; Rodriguez-Roche, Rosmari; Díaz, Gisell; Vázquez, Antonio A; Alvarez, Mayling; Rodríguez, Magdalena; Bisset, Juan A; Guzman, Maria G

2017-10-01

While horizontal transmission (human-mosquito-human) of dengue viruses largely determines the epidemiology of the disease, vertical transmission (infected female mosquito- infected offspring) has been suggested as a mechanism that ensures maintenance of the virus during adverse conditions for horizontal transmission to occur. The purpose of this study was to analyze the natural infection of larval stages of Aedes aegypti (Diptera: Culicidae) with the dengue virus (DENV) in Cuba. Here, we report vertical transmission of DENV-3 genotype III in natural populations of Ae. aegypti through RT-PCR detection and serotyping plus sequencing. Our report constitutes the first record of vertical transmission of DENV in Ae. aegypti from Cuba with details of its serotype and genotype. Copyright © 2017 Elsevier B.V. All rights reserved.

The genetics of chemoreception in the labella and tarsi of Aedes aegypti.

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Sparks, Jackson T; Bohbot, Jonathan D; Dickens, Joseph C

2014-05-01

The yellow-fever mosquito Aedes aegypti is a major vector of human diseases, such as dengue, yellow fever, chikungunya and West Nile viruses. Chemoreceptor organs on the labella and tarsi are involved in human host evaluation and thus serve as potential foci for the disruption of blood feeding behavior. In addition to host detection, these contact chemoreceptors mediate feeding, oviposition and conspecific recognition; however, the molecular landscape of chemoreception in these tissues remains mostly uncharacterized. Here we report the expression profile of all putative chemoreception genes in the labella and tarsi of both sexes of adult Ae. aegypti and discuss their possible roles in the physiology and behavior of this important disease vector. Published by Elsevier Ltd.

TALEN-Based Gene Disruption in the Dengue Vector Aedes aegypti

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Aryan, Azadeh; Anderson, Michelle A. E.; Myles, Kevin M.; Adelman, Zach N.

2013-01-01

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 khw 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. PMID:23555893

TALEN-based gene disruption in the dengue vector Aedes aegypti.

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Azadeh Aryan

Full Text Available In addition to its role as the primary vector for dengue viruses, Aedes aegypti has a long history as a genetic model organism for other bloodfeeding mosquitoes, due to its ease of colonization, maintenance and reproductive productivity. Though its genome has been sequenced, functional characterization of many Ae. aegypti genes, pathways and behaviors has been slow. TALE nucleases (TALENs have been used with great success in a number of organisms to generate site-specific DNA lesions. We evaluated the ability of a TALEN pair to target the Ae. aegypti kmo gene, whose protein product is essential in the production of eye pigmentation. Following injection into pre-blastoderm embryos, 20-40% of fertile survivors produced kmo alleles that failed to complement an existing kh(w mutation. Most of these individuals produced more than 20% white-eyed progeny, with some producing up to 75%. Mutant alleles were associated with lesions of 1-7 bp specifically at the selected target site. White-eyed individuals could also be recovered following a blind intercross of G1 progeny, yielding several new white-eyed strains in the genetic background of the sequenced Liverpool strain. We conclude that TALENs are highly active in the Ae. aegypti germline, and have the potential to transform how reverse genetic experiments are performed in this important disease vector.

TALEN-based gene disruption in the dengue vector Aedes aegypti.

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Aryan, Azadeh; Anderson, Michelle A E; Myles, Kevin M; Adelman, Zach N

2013-01-01

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.

Exploring the molecular basis of insecticide resistance in the dengue vector Aedes aegypti: a case study in Martinique Island (French West Indies).

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Marcombe, Sébastien; Poupardin, Rodolphe; Darriet, Frederic; Reynaud, Stéphane; Bonnet, Julien; Strode, Clare; Brengues, Cecile; Yébakima, André; Ranson, Hilary; Corbel, Vincent; David, Jean-Philippe

2009-10-26

The yellow fever mosquito Aedes aegypti is a major vector of dengue and hemorrhagic fevers, causing up to 100 million dengue infections every year. As there is still no medicine and efficient vaccine available, vector control largely based on insecticide treatments remains the only method to reduce dengue virus transmission. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides. Resistance of Ae. aegypti to chemical insecticides has been reported worldwide and the underlying molecular mechanisms, including the identification of enzymes involved in insecticide detoxification are not completely understood. The present paper investigates the molecular basis of insecticide resistance in a population of Ae. aegypti collected in Martinique (French West Indies). Bioassays with insecticides on adults and larvae revealed high levels of resistance to organophosphate and pyrethroid insecticides. Molecular screening for common insecticide target-site mutations showed a high frequency (71%) of the sodium channel 'knock down resistance' (kdr) mutation. Exposing mosquitoes to detoxification enzymes inhibitors prior to bioassays induced a significant increased susceptibility of mosquitoes to insecticides, revealing the presence of metabolic-based resistance mechanisms. This trend was biochemically confirmed by significant elevated activities of cytochrome P450 monooxygenases, glutathione S-transferases and carboxylesterases at both larval and adult stages. Utilization of the microarray Aedes Detox Chip containing probes for all members of detoxification and other insecticide resistance-related enzymes revealed the significant constitutive over-transcription of multiple detoxification genes at both larval and adult stages. The over-transcription of detoxification genes in the resistant strain was confirmed by using real-time quantitative RT-PCR. These results suggest that the high level of

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

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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.

Site-specific cassette exchange systems in the Aedes aegypti mosquito and the Plutella xylostella moth.

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Roya Elaine Haghighat-Khah

Full Text Available Genetically engineered insects are being evaluated as potential tools to decrease the economic and public health burden of mosquitoes and agricultural pest insects. Here we describe a new tool for the reliable and targeted genome manipulation of pest insects for research and field release using recombinase mediated cassette exchange (RMCE mechanisms. We successfully demonstrated the established ΦC31-RMCE method in the yellow fever mosquito, Aedes aegypti, which is the first report of RMCE in mosquitoes. A new variant of this RMCE system, called iRMCE, combines the ΦC31-att integration system and Cre or FLP-mediated excision to remove extraneous sequences introduced as part of the site-specific integration process. Complete iRMCE was achieved in two important insect pests, Aedes aegypti and the diamondback moth, Plutella xylostella, demonstrating the transferability of the system across a wide phylogenetic range of insect pests.

Site-Specific Cassette Exchange Systems in the Aedes aegypti Mosquito and the Plutella xylostella Moth

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Haghighat-Khah, Roya Elaine; Scaife, Sarah; Martins, Sara; St John, Oliver; Matzen, Kelly Jean; Morrison, Neil; Alphey, Luke

2015-01-01

Genetically engineered insects are being evaluated as potential tools to decrease the economic and public health burden of mosquitoes and agricultural pest insects. Here we describe a new tool for the reliable and targeted genome manipulation of pest insects for research and field release using recombinase mediated cassette exchange (RMCE) mechanisms. We successfully demonstrated the established ΦC31-RMCE method in the yellow fever mosquito, Aedes aegypti, which is the first report of RMCE in mosquitoes. A new variant of this RMCE system, called iRMCE, combines the ΦC31-att integration system and Cre or FLP-mediated excision to remove extraneous sequences introduced as part of the site-specific integration process. Complete iRMCE was achieved in two important insect pests, Aedes aegypti and the diamondback moth, Plutella xylostella, demonstrating the transferability of the system across a wide phylogenetic range of insect pests. PMID:25830287

Insights into the transcriptome of oenocytes from Aedes aegypti pupae

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Gustavo Ferreira Martins

2011-05-01

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

Confusion, knock-down and kill of Aedes aegypti using metofluthrin in domestic settings: a powerful tool to prevent dengue transmission?

OpenAIRE

Ritchie, Scott A; Devine, Gregor J

2013-01-01

Background Dengue control methods are reliant upon control of the vector, primarily Aedes aegypti. Current adulticiding methods in North Queensland include treating premises with residual synthetic pyrethroid insecticides (interior residual spraying; IRS), a laborious, intrusive task. The vapor active synthetic pyrethroid metofluthrin might offer an efficient alternative as some studies indicate that it prevents biting and has strong knockdown effects. However, its expellant and/or irritant e...

Aerial ULV control of Aedes aegypti with naled (Dibrom) inside simulated rural village and urban cryptic habitats.

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Britch, Seth C; Linthicum, Kenneth J; Aldridge, Robert L; Breidenbaugh, Mark S; Latham, Mark D; Connelly, Peter H; Rush, Mattie J E; Remmers, Jennifer L; Kerce, Jerry D; Silcox, Charles A

2018-01-01

We conducted aerial fixed wing ultra low volume (ULV) spray trials with naled to investigate penetration of exposed and simulated cryptic habitat within opened buildings, partially sealed buildings, and outdoor locations targeting sentinel adult Aedes aegypti mosquitoes in north central Florida. Mortality was observed in open and closed buildings and outdoors, even in mosquitoes placed in cryptic habitats. Observations on the impact of building type, mosquito exposure method such as placement in cryptic habitat, and spray nozzle size on mosquito mortality are described and analyzed.

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

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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...

Insecticide susceptibility of the dengue vector Aedes aegypti (Diptera: culicidae in Makkah City, Saudi Arabia

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Al Thbiani Aziz

2011-06-01

Full Text Available Objective: To examine the insecticide susceptibility of Aedes aegypti (Ae. aegypti from various sites in Makkah City, Saudi Arabia. Methods: This was examined based on WHO standard procedures. Results: The larvae of Ae. aegypti were susceptible to all larvicides examined, but this susceptibility was more pronounced in wild populations, which tended to show tolerance to icon. Icon was the most effective larvicide with LC 50 values of 0.007 ppm and 0.012 ppm for the laboratory and field strains, respectively. Ae. aegypti adults exposed to lambda-cyhalothrin showed a low mortality rate in comparison with those exposed to deltamethrin and cyfluthrin. Conclusions: The results of the present study indicate differential susceptibility between field and laboratory larval populations. Wild larvae are less susceptible to insecticide treatments than their laboratory-bred counterparts. Taken together, these results suggest that tolerance and the tendency toward resistance to commonly used insecticides are present in Ae. aegypti populations throughout Makkah City, Saudi Arabia.

Dual African origins of global Aedes aegypti s.l. populations revealed by mitochondrial DNA.

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Michelle Moore

Full Text Available 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.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.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.

Novel Wolbachia-transinfected Aedes aegypti mosquitoes possess diverse fitness and vector competence phenotypes.

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Johanna E Fraser

2017-12-01

Full Text Available Wolbachia pipientis from Drosophila melanogaster (wMel is an endosymbiotic bacterium that restricts transmission of human pathogenic flaviviruses and alphaviruses, including dengue, Zika, and chikungunya viruses, when introduced into the mosquito vector Aedes aegypti. To date, wMel-infected Ae. aegypti have been released in field trials in 5 countries to evaluate the effectiveness of this strategy for disease control. Despite the success in establishing wMel-infected mosquitoes in wild populations, and the well-characterized antiviral capabilities of wMel, transinfecting different or additional Wolbachia strains into Ae. aegypti may improve disease impact, and perhaps more importantly, could provide a strategy to account for the possible evolution of resistant arboviruses. Here, we report the successful transinfection of Ae. aegypti with the Wolbachia strains wMelCS (D. melanogaster, wRi (D. simulans and wPip (Culex quinquefasciatus and assess the effects on Ae. aegypti fitness, cytoplasmic incompatibility, tissue tropism and pathogen blocking in a laboratory setting. The results demonstrate that wMelCS provides a similar degree of protection against dengue virus as wMel following an infectious blood meal, and significantly reduces viral RNA levels beyond that of wMel following a direct challenge with infectious virus in mosquitoes, with no additional fitness cost to the host. The protection provided by wRi is markedly weaker than that of wMelCS, consistent with previous characterisations of these lines in Drosophila, while wPip was found to substantially reduce the fitness of Ae. aegypti. Thus, we determine wMelCS as a key candidate for further testing in field-relevant fitness tests and viremic blood feeding challenges in a clinical setting to determine if it may represent an alternative Wolbachia strain with more desirable attributes than wMel for future field testing.

Novel Wolbachia-transinfected Aedes aegypti mosquitoes possess diverse fitness and vector competence phenotypes.

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Fraser, Johanna E; De Bruyne, Jyotika Taneja; Iturbe-Ormaetxe, Iñaki; Stepnell, Justin; Burns, Rhiannon L; Flores, Heather A; O'Neill, Scott L

2017-12-01

Wolbachia pipientis from Drosophila melanogaster (wMel) is an endosymbiotic bacterium that restricts transmission of human pathogenic flaviviruses and alphaviruses, including dengue, Zika, and chikungunya viruses, when introduced into the mosquito vector Aedes aegypti. To date, wMel-infected Ae. aegypti have been released in field trials in 5 countries to evaluate the effectiveness of this strategy for disease control. Despite the success in establishing wMel-infected mosquitoes in wild populations, and the well-characterized antiviral capabilities of wMel, transinfecting different or additional Wolbachia strains into Ae. aegypti may improve disease impact, and perhaps more importantly, could provide a strategy to account for the possible evolution of resistant arboviruses. Here, we report the successful transinfection of Ae. aegypti with the Wolbachia strains wMelCS (D. melanogaster), wRi (D. simulans) and wPip (Culex quinquefasciatus) and assess the effects on Ae. aegypti fitness, cytoplasmic incompatibility, tissue tropism and pathogen blocking in a laboratory setting. The results demonstrate that wMelCS provides a similar degree of protection against dengue virus as wMel following an infectious blood meal, and significantly reduces viral RNA levels beyond that of wMel following a direct challenge with infectious virus in mosquitoes, with no additional fitness cost to the host. The protection provided by wRi is markedly weaker than that of wMelCS, consistent with previous characterisations of these lines in Drosophila, while wPip was found to substantially reduce the fitness of Ae. aegypti. Thus, we determine wMelCS as a key candidate for further testing in field-relevant fitness tests and viremic blood feeding challenges in a clinical setting to determine if it may represent an alternative Wolbachia strain with more desirable attributes than wMel for future field testing.

The Aquaporin Gene Family of the Yellow Fever Mosquito, Aedes aegypti

OpenAIRE

Drake, Lisa L.; Boudko, Dmitri Y.; Marinotti, Osvaldo; Carpenter, Victoria K.; Dawe, Angus L.; Hansen, Immo A.

2010-01-01

Background The mosquito, Aedes aegypti, is the principal vector of the Dengue and yellow fever viruses. During feeding, an adult female can take up more than its own body weight in vertebrate blood. After a blood meal females excrete large amounts of urine through their excretion system, the Malpighian tubules (MT). Diuresis starts within seconds after the mosquito starts feeding. Aquaporins (AQPs) are a family of membrane transporters that regulate the flow of water, glycerol and other small...

Complex modulation of the Aedes aegypti transcriptome in response to dengue virus infection.

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Bonizzoni, Mariangela; Dunn, W Augustine; Campbell, Corey L; Olson, Ken E; Marinotti, Osvaldo; James, Anthony A

2012-01-01

Dengue fever is the most important arboviral disease world-wide, with Aedes aegypti being the major vector. Interactions between the mosquito host and dengue viruses (DENV) are complex and vector competence varies among geographically-distinct Ae. aegypti populations. Additionally, dengue is caused by four antigenically-distinct viral serotypes (DENV1-4), each with multiple genotypes. Each virus genotype interacts differently with vertebrate and invertebrate hosts. Analyses of alterations in mosquito transcriptional profiles during DENV infection are expected to provide the basis for identifying networks of genes involved in responses to viruses and contribute to the molecular-genetic understanding of vector competence. In addition, this knowledge is anticipated to support the development of novel disease-control strategies. RNA-seq technology was used to assess genome-wide changes in transcript abundance at 1, 4 and 14 days following DENV2 infection in carcasses, midguts and salivary glands of the Ae. aegypti Chetumal strain. DENV2 affected the expression of 397 Ae. aegypti genes, most of which were down-regulated by viral infection. Differential accumulation of transcripts was mainly tissue- and time-specific. Comparisons of our data with other published reports reveal conservation of functional classes, but limited concordance of specific mosquito genes responsive to DENV2 infection. These results indicate the necessity of additional studies of mosquito-DENV interactions, specifically those focused on recently-derived mosquito strains with multiple dengue virus serotypes and genotypes.

Complex modulation of the Aedes aegypti transcriptome in response to dengue virus infection.

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Mariangela Bonizzoni

Full Text Available Dengue fever is the most important arboviral disease world-wide, with Aedes aegypti being the major vector. Interactions between the mosquito host and dengue viruses (DENV are complex and vector competence varies among geographically-distinct Ae. aegypti populations. Additionally, dengue is caused by four antigenically-distinct viral serotypes (DENV1-4, each with multiple genotypes. Each virus genotype interacts differently with vertebrate and invertebrate hosts. Analyses of alterations in mosquito transcriptional profiles during DENV infection are expected to provide the basis for identifying networks of genes involved in responses to viruses and contribute to the molecular-genetic understanding of vector competence. In addition, this knowledge is anticipated to support the development of novel disease-control strategies. RNA-seq technology was used to assess genome-wide changes in transcript abundance at 1, 4 and 14 days following DENV2 infection in carcasses, midguts and salivary glands of the Ae. aegypti Chetumal strain. DENV2 affected the expression of 397 Ae. aegypti genes, most of which were down-regulated by viral infection. Differential accumulation of transcripts was mainly tissue- and time-specific. Comparisons of our data with other published reports reveal conservation of functional classes, but limited concordance of specific mosquito genes responsive to DENV2 infection. These results indicate the necessity of additional studies of mosquito-DENV interactions, specifically those focused on recently-derived mosquito strains with multiple dengue virus serotypes and genotypes.

Effective population sizes of a major vector of human diseases, Aedes aegypti.

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Saarman, Norah P; Gloria-Soria, Andrea; Anderson, Eric C; Evans, Benjamin R; Pless, Evlyn; Cosme, Luciano V; Gonzalez-Acosta, Cassandra; Kamgang, Basile; Wesson, Dawn M; Powell, Jeffrey R

2017-12-01

The effective population size ( N e ) is a fundamental parameter in population genetics that determines the relative strength of selection and random genetic drift, the effect of migration, levels of inbreeding, and linkage disequilibrium. In many cases where it has been estimated in animals, N e is on the order of 10%-20% of the census size. In this study, we use 12 microsatellite markers and 14,888 single nucleotide polymorphisms (SNPs) to empirically estimate N e in Aedes aegypti , the major vector of yellow fever, dengue, chikungunya, and Zika viruses. We used the method of temporal sampling to estimate N e on a global dataset made up of 46 samples of Ae. aegypti that included multiple time points from 17 widely distributed geographic localities. Our N e estimates for Ae. aegypti fell within a broad range (~25-3,000) and averaged between 400 and 600 across all localities and time points sampled. Adult census size (N c ) estimates for this species range between one and five thousand, so the N e / N c ratio is about the same as for most animals. These N e values are lower than estimates available for other insects and have important implications for the design of genetic control strategies to reduce the impact of this species of mosquito on human health.

Exploiting silver nanoparticles with PMAA against aedes aegypti larvae development: potential larvicidal activity

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Carvalho, Mariana T.; de Santana, Gisele S.; de Andrade, Audrey N.; Cabral, Amanda; da Silva Rosa-Leão, Nairane; de Melo-Santos, Maria Alice V.; Gomes, Anderson S. L.

2018-02-01

Aedes aegypti is one of the mosquito species with major epidemiological importance in Brazil, involved with the transmission of the arboviruses such as Dengue, Chikungunya and Zika. Since the mosquito is well adapted to the urban environments, where there are large amounts of breeding sites for larvae and pupae, its control has become increasingly difficult. Since 1996, the usual control is made by using chemical larvicides, but the continued use of some of these compounds has led to the selection of A. aegypti resistant populations. Therefore, the search for new insecticidal substances is necessary to guarantee the control of this specie. Our goal is to establish a new larvicide with high toxicity without the drawback of resistance. For this, we developed a low-cost green synthesized silver nanoparticles with a poly(methacrylic acid) outer layer, catalyzed with ultra violet light. We tested nanoparticles samples produced from different batches in laboratory bioassays against fourth-instar larvae. The results showed a desired toxic activity, presenting 10% to 100% of mortalities in concentrations ranging from 0.01 to 1.1 ppm, and from the bioassay we have obtained LC50 = 0.027 ppm and LC90 = 0.044 ppm, after 24 hours of exposure. Imaging the threated larvae by optical microscopy and optical coherence tomography helped to clarify the potential larvae death mechanism. These results associated with the simplicity and low cost of production of these silver nanoparticles, reveal their great potential for the development of products to control of A. aegypti larvae.

Absence of impact of aerial malathion treatment on Aedes aegypti during a dengue outbreak in Kingston, Jamaica

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Trevor Castle

1999-02-01

Full Text Available During an outbreak of dengue fever in Jamaica from October to December 1995, a study was carried out to determine the impact of aerial ultra-low volume malathion treatment on adult Aedes aegypti. This was done by monitoring oviposition rates of the vector in three urban communities in Kingston and by exposing caged mosquitoes both directly and indirectly to the aerial malathion treatment. The insecticide was delivered at a rate of 219 mL/ha between 7:10 a.m. and 8:45 a.m. The results of the study clearly showed that the insecticide application was ineffective in interfering with Aedes aegypti oviposition, and adult mosquitoes held in cages inside dwellings were largely unaffected. Consequently, this type of intervention seemed to have little significant impact in arresting or abating dengue transmission.

Resistance to deltamethrine in two populations of Aedes aegypti (Diptera, Culicidae from Peru

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Julio Chávez

2013-05-01

Full Text Available The objective of the present work was to determine the resistance levels to deltamethrine in two populations of Aedes aegypti from Peru. Bioassays in adults were carried out following the methodology of the World Health Organization. We met resistance in the Sullana population with 70% of mortality and susceptibility in the population The Future El Porvenir with 99% of mortality.

BIOKONTROL JENTIK NYAMUK Aedes aegypti DENGAN PREDATOR IKAN PEMAKAN JENTIK SEBAGAI PENDUKUNG MATERI AJAR INSEKTA

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Suharno Zen

2012-05-01

Full Text Available Dengue fever is an infectious disease caused by a virus and is transmitted by the Aedes aegypti mosquito. Dengue fever has not yet found a cure and the only prevention is through mosquito vector  control. Health Department policy to prevent and eradicate dengue fever today is to make eradication by means of mechanical, physical, chemical or biological. Biological is one of alternative  control of mosquito vectors that are safe for humans and the environment but still effective in suppressing the mosquito vector. One attempt to do that is by using animals to fight other creatures, or better known as biological control. In the present research was performed using fish of Betta spp, Cyprinus carpio and Oreochormis niloticus as a natural predator of the Aedes aegypti mosquito. The design of this research is  Completely Randomized Design (CRD with three treatments are 3 types of fish with 5 times repeated. Data were analyzed with analysis of the range and tested further with the Smallest Real Differences Test (LSD on the real level 5%. The result of this research is the ability Betta spp eating is higher than the Oreochromis niloticus and Cyprinus carpio by the number of larvae that consumed between 34.6 to 36.9 mosquito larvae tail. The ability to eat at various types of fish against mosquito larvae, influenced by several factors: the agressive, espesialisasi fish to food, the active duration and the amount of time the fish is active in 24 hours.

Diagnostic Doses of Insecticides for Adult Aedes aegypti to Assess Insecticide Resistance in Cuba.

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Rodríguez, María Magdalena; Crespo, Ariel; Hurtado, Daymi; Fuentes, Ilario; Rey, Jorge; Bisset, Juan Andrés

2017-06-01

The objective of this study was to determine diagnostic doses (DDs) of 5 insecticides for the Rockefeller susceptible strain of Aedes aegypti , using the Centers for Disease Control and Prevention (CDC) bottle bioassay as a tool for monitoring insecticide resistance in the Cuban vector control program. The 30-min DD values determined in this study were 13.5 μg/ml, 6.5 μg/ml, 6 μg/ml, 90.0 μg/ml, and 15.0 μg/ml for cypermethrin, deltamethrin, lambda-cyhalothrin, chlorpyrifos, and propoxur, respectively. To compare the reliability of CDC bottle bioassay with the World Health Organization susceptible test, 3 insecticide-resistant strains were evaluated for deltamethrin and lambda-cyhalothrin. Results showed that the bottles can be used effectively from 21 to 25 days after treatment and reused up to 4 times, depending on the storage time. The CDC bottle bioassay is an effective tool to assess insecticide resistance in field populations of Ae. aegypti in Cuba and can be incorporated into vector management programs using the diagnostic doses determined in this study.

Determinación de la resistencia a insecticidas en Aedes aegypti, Anopheles albimanus y Lutzomyia peruensis procedentes del Norte Peruano

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Franklin Vargas V

2006-10-01

Full Text Available Objetivo: Determinar los niveles de resistencia a temephos y deltametrina en cinco poblaciones naturales de Aedes aegypti del norte de Perú (La Libertad y Piura, dos cepas de Anopheles albimanus (Sullana y Tambogrande y una cepa de Lutzomyía spp (Santiago de Chuco, La Libertad. Materiales y métodos: Se realizaron bioensayos en larvas y adultos siguiendo la metodología de la Organización Mundial de la Salud. La visualización de bandas de B-esterasas se hizo por electroforesis en gel de poliacrilamida en larvas de cuarto estadio. Resultados: Las poblaciones de Ae. aegypti de Sullana y Tambogrande (Piura presentaron factores de resistencia (FR a temephos de 6,84 con un KDT50 = 160,42 minutos y 70% de mortalidad a las 24 horas; en tanto en la población de Tambogrande se observó un FR de 5,60, KDT50 = 107,20 y 80% de mortalidad, a diferencia de las cepas de La Esperanza, El Porvenir y Florencia de Mora (La Libertad que fueron susceptibles. Se identificó resistencia en las poblaciones de Ae. aegypti y A. albimanus procedentes de Piura (Tambogrande y Sullana para deltametrina, a diferencia de las poblaciones de Ae.aegypti y Lutzomyia spp de La Libertad que fueron susceptibles. Se identificó la esterasa B2 con un Rf de 0,23 en la población de Ae. aegypti de Sullana. Conclusiones: Dada la susceptibilidad de la población de La Libertad al insecticida temephos, puede seguir siendo usado en el control vectorial de Aedes aegypti; por lo contrario, dada la resistencia observada en poblaciones de Anopheles en Sullana y Tambogrande se debe evaluar el uso de la deltametrina en estas poblaciones. Finalmente, la población de Lutzomyia spp. no presentó resistencia a deltametrina.

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

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Hortance Manda

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

Macrofactores determinantes de la infestación por Aedes aegypti en centros laborales del municipio de Santiago de Cuba

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Lino Robert Larrea Aguilera

2014-04-01

Full Text Available Se efectuó un estudio analítico, de casos y controles, de 116 centros laborales del municipio de Santiago de Cuba, durante junio del 2011, para identificar los macrofactores determinantes en los índices de infestación por Aedes aegypti en tanques bajos y elevados, cisternas y otros depósitos de agua sin condiciones de hermeticidad, que se convierten en focos generadores del mosquito. Para ello se seleccionaron 48 instituciones con criaderos (casos y 96 sin estos (2 controles por caso, además de los macrofactores: comportamiento de los trabajadores y la comunidad, agentes medioambientales y organizacionales de la entidad laboral y del Programa Nacional para la Erradicación del Mosquito Aedes aegypti. En la serie los resultados se validaron mediante la oportunidad relativa, el riesgo atribuible en expuesto porcentual y la diferencia de medias, lo cual permitió concluir que el control adecuado de los tanques bajos y elevados no protegidos, el funcionamiento del autofocal laboral, la limpieza y desobstrucción de los tragantes y drenes, de los solares yermos o terrenos enyerbados, así como la elevación de la calidad del trabajo de los operarios A, lograrían reducir la infestación en los centros laborales

Interpolación espacial de la abundancia larval de Aedes aegypti para localizar focos de infestación Spatial interpolation of Aedes aegypti larvae abundance for locating infestation foci

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Larry Niño

2011-06-01

Full Text Available OBJETIVO: Diseñar e implementar una metodología de vigilancia que localice los focos de infestación de Aedes aegypti con el empleo de larvitrampas y técnicas de interpolación espacial, las cuales permiten estimar la abundancia vectorial de forma continua en el espacio a partir del conteo de individuos colectados en el área de estudio. MÉTODOS: Se instalaron 228 larvitrampas -a razón de una por manzana- en la zona más densamente poblada de la comuna cinco de Villavicencio (Meta. Con la información regionalizada de la abundancia de larvas se realizaron interpolaciones espaciales con las técnicas polígonos de Voronoi, Kriging ordinario y ponderación de distancias inversas. RESULTADOS: Se presenta una metodología alternativa para la vigilancia del vector del dengue, basada en el uso de larvitrampas y técnicas de interpolación espacial, con las cuales se obtuvieron mapas de superficie sustentados en observaciones puntuales. CONCLUSIONES: Los resultados muestran que esta estrategia aventaja a los índices normalmente usados, dado que permite visualizar de manera continua el nivel de infestación vectorial y por ende el riesgo de transmisión de dengue de acuerdo al grado de infestación por A. aegypti. Es de esperar que su adopción contribuya a planificar, optimizar y evaluar con mayor efectividad las actividades de prevención y control.OBJECTIVE: Design and implement a surveillance method for locating Aedes aegypti infestation foci with the use of larvae traps and spatial interpolation techniques, which facilitate the ongoing estimation of vector abundance in the area by counting the individuals collected in the study area. METHODs: A total of 228 larvae traps were installed-at a rate of one per block-in the most densely populated area of commune five of Villavicencio (Meta. With regionalized information on larvae abundance, spatial interpolations were conducted with the Voronoi polygon, ordinary kriging, and inverse distance

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

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Anthony J. Cornel

2016-08-01

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

Insecticide resistance is mediated by multiple mechanisms in recently introduced Aedes aegypti from Madeira Island (Portugal).

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Seixas, Gonçalo; Grigoraki, Linda; Weetman, David; Vicente, José Luís; Silva, Ana Clara; Pinto, João; Vontas, John; Sousa, Carla Alexandra

2017-07-01

Aedes aegypti is a major mosquito vector of arboviruses, including dengue, chikungunya and Zika. In 2005, Ae. aegypti was identified for the first time in Madeira Island. Despite an initial insecticide-based vector control program, the species expanded throughout the Southern coast of the island, suggesting the presence of insecticide resistance. Here, we characterized the insecticide resistance status and the underlying mechanisms of two populations of Ae. aegypti from Madeira Island, Funchal and Paúl do Mar. WHO susceptibility bioassays indicated resistance to cyfluthrin, permethrin, fenitrothion and bendiocarb. Use of synergists significantly increased mortality rates, and biochemical assays indicated elevated activities of detoxification enzymes, suggesting the importance of metabolic resistance. Microarray-based transcriptome analysis detected significant upregulation in both populations of nine cytochrome P450 oxidase genes (including four known pyrethroid metabolizing enzymes), the organophosphate metabolizer CCEae3a, Glutathione-S-transferases, and multiple putative cuticle proteins. Genotyping of knockdown resistance loci linked to pyrethroid resistance revealed fixation of the 1534C mutation, and presence with moderate frequencies of the V1016I mutation in each population. Significant resistance to three major insecticide classes (pyrethroid, carbamate and organophosphate) is present in Ae. aegypti from Madeira Island, and appears to be mediated by multiple mechanisms. Implementation of appropriate resistance management strategies including rotation of insecticides with alternative modes of action, and methods other than chemical-based vector control are strongly advised to delay or reverse the spread of resistance and achieve efficient control.

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.

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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. Copyright © 2016 Elsevier B.V. All rights reserved.

Insecticide resistance to permethrin and malathion and associated mechanisms in Aedes aegypti mosquitoes from St. Andrew Jamaica.

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Sheena Francis

Full Text Available The emergence of novel diseases spread by the Aedes aegypti mosquito in Jamaica and the Caribbean, has prompted studies on insecticide resistance towards effective management of the vector. Though Jamaica has been using the organophosphate insecticide malathion in its vector control program for more than 30 years, resistance to the pesticide has not been tested in over a decade. We analyzed resistance to malathion and the pyrethroid insecticide, permethrin on mosquitoes collected across St. Andrew, Jamaica, and analyzed the molecular basis of resistance. The Center for Disease Control (CDC bioassay revealed that Ae. aegypti mosquitoes from St. Andrew, Jamaica were resistant to permethrin (15 μg/bottle with mortalities at 0-8% at 30 minute exposure time, while contact with malathion (50 μg/bottle revealed ≤ 50% mortality at 15 minutes, which increased to 100% at 45 minutes. The standard susceptible New Orleans (NO strain exhibited 100% mortality within15 minutes. The activities of multifunction oxidases and p-nitro phenyl-acetate esterases were significantly greater in most Jamaican populations in comparison to the NO strain, while activities of glutathione-S-transferase, acetylcholinesterase, α-esterase and ß-esterase activity were relatively equal, or lower than that of the control strain. The frequency of knockdown resistance mutations in the voltage dependent sodium channel gene were measured. All collections were fixed for Cys1,534 while 56% of mosquitoes were Ile1,016/Val1,016 heterozygotes, and 33% were Ile1,016 homozygotes. Aedes aegypti from St. Andrew Jamaica are resistant to permethrin with variations in the mode of mechanism, and possibly developing resistance to malathion. Continued monitoring of resistance is critically important to manage the spread of the vector in the country.

Control of Aedes aegypti with temephos in a Buenos Aires cemetery, Argentina Control de Aedes aegypti con temefós en un cementerio de Buenos Aires, Argentina Controle de Aedes aegypti com temefós em cemitério de Buenos Aires, Argentina

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Darío Vezzani

2004-10-01

Full Text Available The efficacy of a larvicide, temephos, for controlling Ae. aegypti was evaluated in a cemetery in Buenos Aires, Argentina. Breeding sites decreased from 18.4% in the first study period (Nov 1998 to May 1999, without temephos to 2.2% in the second period (Nov 1999 to May 2000, two applications, and to 0.05% in the third one (Nov 2000 to May 2001, five applications. Ovitraps with eggs decreased from 17% in the first period to 5.8% in the second period, and to 2.9% in the third one. Results suggest that, in Buenos Aires, Ae. aegypti populations are highly susceptible to temephos. It is recommended to limit the use of temephos to prevent potential epidemics rather than for routine control.Se evaluó la eficacia de un larvicida, temefós, para controlar Ae. aegypti en un cementerio de Buenos Aires, Argentina. Los criaderos descendieron de 18,4% en el primer periodo de estudio (Nov 1998 a May 1999, sin temefos a 2,2% en el segundo (Nov 1999 a May 2000, dos aplicaciones, y a 0,05% en el tercero (Nov 2000 a May 2001, cinco aplicaciones. Las ovitrampas con huevos disminuyeron de 17% en el primer periodo a 5,8% en el segundo, y a 2,9% en el tercero. Los resultados sugieren que, en Buenos Aires, las poblaciones de Ae. aegypti son altamente susceptibles al temefós. Es recomendable limitar su uso para prevenir eventuales epidemias y no para el control rutinario.Avaliou-se a eficácia de um larvicida, temefós, para controlar Ae. aegypti em um cemitério de Buenos Aires, Argentina. Os criadouros reduziram de 18,4% no primeiro período de estudo (nov de 1998 a maio de 1999, sem temefós para 2,2% no segundo (nov de 1999 a maio de 2000, duas aplicações, e para 0,05% no terceiro (nov de 2000 a maio de 2001, cinco aplicações. As. ovitrampas com ovos diminuíram de 17% no primeiro período para 5,8% no segundo e para 2,9% no terceiro. Os resultados sugerem que, em Buenos Aires, as populações de Ae. aegypti são altamente susceptíveis ao temefós. �

Identification of insecticidal principals from cucumber seed oil against the yellow fever mosquito, Aedes aegypti

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The yellow fever mosquito, Aedes aegypti, is one of the most medically important mosquito species due to its ability to spread viruses of yellow fever, dengue fever and Zika in humans. In this study, the insecticidal activity of seventeen plant essential oils were evaluated to toxicity by topical a...

Entomopathogenic fungi and their potential for the management of Aedes aegypti (Diptera: Culicidae in the Americas

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Harry C Evans

Full Text Available Classical biological control has been used extensively for the management of exotic weeds and agricultural pests, but never for alien insect vectors of medical importance. This simple but elegant control strategy involves the introduction of coevolved natural enemies from the centre of origin of the target alien species. Aedes aegypti - the primary vector of the dengue, yellow fever and Zika flaviviruses - is just such an invasive alien in the Americas where it arrived accidentally from its West African home during the slave trade. Here, we introduce the concept of exploiting entomopathogenic fungi from Africa for the classical biological control of Ae. aegypti in the Americas. Fungal pathogens attacking arthropods are ubiquitous in tropical forests and are important components in the natural balance of arthropod populations. They can produce a range of specialised spore forms, as well as inducing a variety of bizarre behaviours in their hosts, in order to maximise infection. The fungal groups recorded as specialised pathogens of mosquito hosts worldwide are described and discussed. We opine that similar fungal pathogens will be found attacking and manipulating Ae. aegypti in African forests and that these could be employed for an economic, environmentally-safe and long-term solution to the flavivirus pandemics in the Americas.

Variation in Aedes aegypti Mosquito Competence for Zika Virus Transmission.

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

2017-04-01

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

Multi-modal Aedes aegypti mosquito reduction interventions and dengue fever prevention.

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Ballenger-Browning, Kara K; Elder, John P

2009-12-01

To systematically review the effectiveness of biological, chemical and educational dengue fever prevention programs on the reduction of entomologic indicators. Searches of PubMed, GoogleScholar, CabDirect databases and reference lists yielded over 1000 articles containing mosquito abatement interventions. Inclusion criteria were: Vector control programs targeting Aedes aegypti and Aedes albopictus mosquitoes; Studies providing pre- and post-test data. Intervention effectiveness was assessed using Mulla's formula to determine percent reductions for all studies with control groups. Twenty-one studies were reviewed. Twelve dependent variables were presented, however, the Breteau, House and Container indices were the primary measurement tools for monitoring larval populations. Behavioural methods consisting of educational campaigns and maintaining water containers to reduce the mosquito population were applied in eight studies. Eight studies involved the use of biological methods such as predatory organisms or bacteria. Finally, eight studies used chemical control techniques including insecticide sprays, larvicides, insecticide-treated materials, and cleaning water of containers with household chemicals with three studies using a combination of intervention techniques. Post-intervention reduction in entomologic indices ranged from 100% to an increase of 13.9% from baseline. Little evidence exists to support the efficacy of mosquito abatement programs owing to poor study designs and lack of congruent entomologic indices. Creation of a standard entomological index, use of clustered and randomized-controlled trials, and testing the generalizability of proven methods are recommended for future research.

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

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

2017-10-01

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

Germline Cas9 expression yields highly efficient genome engineering in a major worldwide disease vector, Aedes aegypti.

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Li, Ming; Bui, Michelle; Yang, Ting; Bowman, Christian S; White, Bradley J; Akbari, Omar S

2017-12-05

The development of CRISPR/Cas9 technologies has dramatically increased the accessibility and efficiency of genome editing in many organisms. In general, in vivo germline expression of Cas9 results in substantially higher activity than embryonic injection. However, no transgenic lines expressing Cas9 have been developed for the major mosquito disease vector Aedes aegypti Here, we describe the generation of multiple stable, transgenic Ae. aegypti strains expressing Cas9 in the germline, resulting in dramatic improvements in both the consistency and efficiency of genome modifications using CRISPR. Using these strains, we disrupted numerous genes important for normal morphological development, and even generated triple mutants from a single injection. We have also managed to increase the rates of homology-directed repair by more than an order of magnitude. Given the exceptional mutagenic efficiency and specificity of the Cas9 strains we engineered, they can be used for high-throughput reverse genetic screens to help functionally annotate the Ae. aegypti genome. Additionally, these strains represent a step toward the development of novel population control technologies targeting Ae. aegypti that rely on Cas9-based gene drives. Copyright © 2017 the Author(s). Published by PNAS.

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

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Hong-Wai Tham

2014-12-01

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

Factors favoring houseplant container infestation with Aedes aegypti larvae in Marília, São Paulo, Brazil Factores que favorecen la infestación de recipientes con plantas domésticas por larvas de Aedes aegypti en Marília, São Paulo, Brasil

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M. L. G. Macoris

1997-04-01

Full Text Available Since reinvasion of São Paulo State by the Aedes aegypti (L. mosquito in 1985, flower pots and vases have been important larval habitats despite educational messages focusing on their control. The objectives of this study were to characterize flower pots and vases as larval habitats with respect to the quantities present and infested, the types of plants involved, and the specific locations of the mosquito larvae; to explore local names for houseplants; and to examine factors affecting acceptance of control measures. The results showed an average of more than four potential plant-related larval habitats per premises, of which only 0.4% were occupied by the vector. Plant-related containers represented 31% of all the containers with Aedes aegypti larvae. Although a sample of 126 respondents was able to list 105 different houseplant names, 49% of the positive plants were of two types: ferns and the ornamental plant Dieffenbachia avoena. The public's apparent unwillingness to accept recommended anti-aegypti control measures involving houseplants seems related to the relative rarity of aegypti larvae in the very common houseplant containers, the control program's poor credibility as a source of information about plants, and a perception that the recommended control measures are harmful to plants. An intervention currently being planned for dengue control will use educational material that refers specifically to those plants whose containers are most commonly found to harbor aegypti larvae; it will also utilize information sources such as botanists with greater credibility regarding plants; and it will set out alternative plant care recommendations that are more likely to appeal as beneficial to the plants and that will stand a better chance of being accepted.Desde 1985, después de la reinfestación de mosquitos Aedes aegypti (L. en el Estado de São Paulo, se encontró que --a pesar de la diseminación de mensajes educativos destinados a su control

Controle de larvas de Aedes aegypti através da utilização de Bacillus thuringiensis em São Sebastião (DF, Brasil - doi: 10.5102/ucs.v10i2.1761

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Rose Gomes Monnerat

2012-12-01

Full Text Available Dengue é uma doença grave, para a qual não existem medicamentos. O controle da doença, portanto, deve ser feito através da eliminação do seu vetor, o mosquito Aedes aegypti. A Embrapa em parceria com a Bthek Biotecnologia desenvolveu o produto Bt-horus SC capaz de controlar as larvas deste inseto. Este produto foi utilizado numa campanha de controle do A. aegypti em São Sebastião (DF, onde a população foi capacitada e participou ativamente do combate ao vetor.

Bioekologi vektor demam berdarah dengue (DBD serta deteksi virus dengue pada Aedes aegypti (Linnaeus dan Ae. albopictus (Skuse (Diptera: Culicidae di kelurahan endemik DBD Bantarjati, Kota Bogor

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Zahara Fadilla

2015-09-01

Full Text Available Dengue hemorrhagic fever (DHF is a viral disease that threatened community health in Indonesia. As part of an eradication program, it is important to learn the behavioral aspect of the disease vector. The aims of this study were to detect the presence of dengue virus in Aedes spp., at Bantarjati Village, Bogor City and to learn to bioecology of. Aedes aegypti (Linnaeus. Detection of dengue virus in Aedes spp. were done by reverse transcription-polymerase chain reaction (RT-PCR technique that consist of two phase were synthesis phase and cDNA amplification and dengue virus serotipe characterization. The Ae. aegypti and Ae. albopictus (Skuse mosquitoes were collected using the landing and resting moquito collection technique booth indoors and outdoors. The highest density of Ae. aegypti and Ae. albopictus were found in April and the peak activity was occurred at 10:00-11:00 am. Dengue virus was not detected in female mosquitoes Aedes spp.

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

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Filipe Vieira Santos de Abreu

2015-08-01

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

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

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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

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

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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. 

Molecular studies with Aedes (Stegomyia) aegypti (Linnaeus, 1762), mosquito transmitting the dengue virus.

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Pereira, Luciana Patrícia Lima Alves; Brito, Maria Cristiane Aranha; Araruna, Felipe Bastos; de Andrade, Marcelo Souza; Moraes, Denise Fernandes Coutinho; Borges, Antônio Carlos Romão; do Rêgo Barros Pires Leal, Emygdia Rosa

2017-08-01

Dengue is an infectious viral disease, which can present a wide clinical picture, ranging from oligo or asymptomatic forms, to bleeding and shock, and can progress to death. The disease problem has increased in recent years, especially in urban and suburban areas of tropical and subtropical regions. There are five dengue viruses, called serotypes (DEN-1, DEN-2, DEN-3, DEN-4, and DEN-5), which belong to the Flaviviridae family and are transmitted to humans through infected mosquito bites, with the main vector the Aedes aegypti mosquito (Linnaeus, 1762). Studies performed with Ae. aegypti, aimed at their identification and analysis of their population structure, are fundamental to improve understanding of the epidemiology of dengue, as well for the definition of strategic actions that reduce the transmission of this disease. Therefore, considering the importance of such research to the development of programs to combat dengue, the present review considers the techniques used for the molecular identification, and evaluation of the genetic variability of Ae. aegypti.

Relative Insecticidal Efficacy of Three Spatial Repellent Integrated Light Sources Against Aedes aegypti.

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Shen, Yuan; Xue, Rui-De; Bibbs, Christopher S

2017-12-01

Three repellent products, OFF! Mosquito Lamp, Insecticandel, and Rescue DecoShield, were comparatively evaluated against Aedes aegypti in 130-m 2 enclosed areas with a 317-m 3 air volume. The results showed that the OFF! Mosquito Lamp with metofluthrin had a greater effect than the Insecticandel with transfluthrin, which had greater effect than the DecoShield with lemongrass oil and several other plant oils against Ae. aegypti. The OFF! Mosquito Lamp was the only product to exceed 50% mortality. An outdoor semi-field evaluation was conducted to determine the effect by distance of the product. Mosquitoes were stationed in cages at 3, 6, 9, 12, and 15 m away from the treatment in a downwind linear array and exposed for 10 min. They were recorded for knockdown after treatment and at 24 h for mortality. The OFF! Mosquito Lamp produced 100% mortality indoors and >80% knockdown and 90% mortality within 6 m while outdoors against Ae. aegypti.

LOTION PREPARATION FROM Piper betle L. ESSENTIAL OIL WITH THE ADDITION OF PATCHOULI OIL AS AN Aedes aegypti REPELLENT

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Mutiara Widawati

2015-01-01

Full Text Available Daun Sirih (Piper betle L. merupakan tanaman yang dapat dimanfaatkan sebagai bahan baku repelan. Penelitian bertujuanuntuk mengetahui potensi minyak atsiri dari daun sirih dengan penambahan minyak nilam sebagai repelan. Penelitianeksperimental dengan rancangan post test only control group design dilakukan tahun 2013, menggunakan sampel nyamukAe. aegypti betina lapar darah. Konsentrasi digunakan yaitu 2%, untuk kontrol positif digunakan losion DEET denganulangan lima kali. Lengan diolesi losion sirih selanjutnya dimasukkan pada kurungan berisi 100 ekor nyamuk uji, kemudiandihitung rata-rata jumlah nyamuk hinggap selama lima menit pengamatan setiap jam periode (uji efikasi repelan dilakukanselama 6 jam. Pada kondisi yang sama, diujikan pula losion biasa tanpa minyak sirih dan fiksatif yang dioleskan ke lenganyang lain terhadap nyamuk Ae. aegypti (kontrol negatif. Efektifitas penolakan hinggapan nyamuk Ae. aegypti dianalisismenggunakan daya proteksi, kemudian dianalisis lebih lanjut dengan uji paired t-test. Losion sirih hasil modifikasi yangdioleskan pada lengan mampu menolak hinggapan nyamuk Ae. aegypti. Losion sirih dengan penambahan minyak nilammemiliki daya proteksi rata-rata 90,33%. Walaupun daya proteksi losion sirih tidak berbeda secara nyata dengan dayaproteksi DEET, tetapi masih memenuhi syarat efektivitas repelan. Minyak sirih dengan penambahan minyak nilamberpotensi untuk digunakan sebagai repelan terhadap nyamuk Ae. aegypti.Kata kunci: losion, daun sirih, minyak nilam, repelan, Aedes aegypti

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)

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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...

Semaphorin-1a is required for Aedes aegypti embryonic nerve cord development.

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Morgan Haugen

Full Text Available Although mosquito genome projects have uncovered orthologues of many known developmental regulatory genes, extremely little is known about mosquito development. In this study, the role of semaphorin-1a (sema1a was investigated during vector mosquito embryonic ventral nerve cord development. Expression of sema1a and the plexin A (plexA receptor are detected in the embryonic ventral nerve cords of Aedes aegypti (dengue vector and Anopheles gambiae (malaria vector, suggesting that Sema1a signaling may regulate mosquito nervous system development. Analysis of sema1a function was investigated through siRNA-mediated knockdown in A. aegypti embryos. Knockdown of sema1a during A. aegypti development results in a number of nerve cord phenotypes, including thinning, breakage, and occasional fusion of the longitudinal connectives, thin or absent commissures, and general distortion of the nerve cord. Although analysis of Drosophila melanogaster sema1a loss-of-function mutants uncovered many similar phenotypes, aspects of the longitudinal phenotypes differed between D. melanogaster and A. aegypti. The results of this investigation suggest that Sema1a is required for development of the insect ventral nerve cord, but that the developmental roles of this guidance molecule have diverged in dipteran insects.

How Much Does Inbreeding Reduce Heterozygosity? Empirical Results from Aedes aegypti

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Powell, Jeffrey R.; Evans, Benjamin R.

2017-01-01

Deriving strains of mosquitoes with reduced genetic variation is useful, if not necessary, for many genetic studies. Inbreeding is the standard way of achieving this. Full-sib inbreeding the mosquito Aedes aegypti for seven generations reduced heterozygosity to 72% of the initial heterozygosity in contrast to the expected 13%. This deviation from expectations is likely due to high frequencies of deleterious recessive alleles that, given the number of markers studied (27,674 single nucleotide polymorphisms [SNPs]), must be quite densely spread in the genome. PMID:27799643

Laboratory and semi-field evaluations of two (Transfluthrin) spatial repellent devices against Aedes aegypti (L.) (Diptera: Culicidae)

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Two transfluthrin-based spatial repellent products (Raid Dual Action Insect Repellent and Home Freshener and Raid Shield (currently not commercially available), SC Johnson, Racine WI) were evaluated for spatial repellent effects against female Aedes aegypti (L.) mosquitoes underlaboratory (wind tunn...

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

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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...

Exploring the molecular basis of insecticide resistance in the dengue vector Aedes aegypti: a case study in Martinique Island (French West Indies

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Yébakima André

2009-10-01

Full Text Available Abstract Background The yellow fever mosquito Aedes aegypti is a major vector of dengue and hemorrhagic fevers, causing up to 100 million dengue infections every year. As there is still no medicine and efficient vaccine available, vector control largely based on insecticide treatments remains the only method to reduce dengue virus transmission. Unfortunately, vector control programs are facing operational challenges with mosquitoes becoming resistant to commonly used insecticides. Resistance of Ae. aegypti to chemical insecticides has been reported worldwide and the underlying molecular mechanisms, including the identification of enzymes involved in insecticide detoxification are not completely understood. Results The present paper investigates the molecular basis of insecticide resistance in a population of Ae. aegypti collected in Martinique (French West Indies. Bioassays with insecticides on adults and larvae revealed high levels of resistance to organophosphate and pyrethroid insecticides. Molecular screening for common insecticide target-site mutations showed a high frequency (71% of the sodium channel 'knock down resistance' (kdr mutation. Exposing mosquitoes to detoxification enzymes inhibitors prior to bioassays induced a significant increased susceptibility of mosquitoes to insecticides, revealing the presence of metabolic-based resistance mechanisms. This trend was biochemically confirmed by significant elevated activities of cytochrome P450 monooxygenases, glutathione S-transferases and carboxylesterases at both larval and adult stages. Utilization of the microarray Aedes Detox Chip containing probes for all members of detoxification and other insecticide resistance-related enzymes revealed the significant constitutive over-transcription of multiple detoxification genes at both larval and adult stages. The over-transcription of detoxification genes in the resistant strain was confirmed by using real-time quantitative RT

Ovitrampas para Avaliação da Presença de Aedes aegypti (Linnaeus e Aedes albopictus (Skuse no Município de Vassouras, Estado do Rio de Janeiro

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Alexandre Oliveira

2014-04-01

Abstract. Aedes aegypti (Linnaeus and Aedes albopictus (Skuse are vectors of many arboviruses including urban yellow fever and dengue, the latter being one of the biggest problems in the world in cities that have hot and humid climate. Having the consecutive cases of dengue in Vassouras, RJ it was important to ascertain the presence and behavior of the vector in different seasons of year and their predominance in the city. In this study we observed the presence of 10.44% Ae. aegypti and 89.56% Ae. albopictus of the 364 viable eggs and being the Matadouro neighborhood (point 4, the local with the largest presence of these culicids. These data showed that Ae. albopictus is ever more present in urban areas.

Avaliação da atividade larvicida do óleo essencial do Zingiber officinale Roscoe (gengibre frente ao mosquito Aedes aegypti

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P.R.B. GOMES

Full Text Available RESUMO Este trabalho analisa o efeito larvicida do óleo Zingiber officinale Roscoe contra larvas em terceiro estágio do mosquito Aedes aegypti. Extraiu-se quantitativamente o óleo essencial por hidrodestilação e calculou-se a CL50 do óleo, a partir dos métodos de Reed-Muench e Pizzi, respectivamente. O óleo essencial obteve CL50 de 76,07 (±2,24 μg mL-1 e rendimento de 0,52% m/v. Os resultados indicam que o óleo essencial avaliado é composto por substâncias que propiciam efeito larvicida contra Aedes aegypti.

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

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Shengzhang Dong

Full Text Available In vivo targeted gene disruption is a powerful tool to study gene function. Thus far, two tools for genome editing in Aedes aegypti have been applied, zinc-finger nucleases (ZFN and transcription activator-like effector nucleases (TALEN. As a promising alternative to ZFN and TALEN, which are difficult to produce and validate using standard molecular biological techniques, the clustered regularly interspaced short palindromic repeats/CRISPR-associated sequence 9 (CRISPR/Cas9 system has recently been discovered as a "do-it-yourself" genome editing tool. Here, we describe the use of CRISPR/Cas9 in the mosquito vector, Aedes aegypti. In a transgenic mosquito line expressing both Dsred and enhanced cyan fluorescent protein (ECFP from the eye tissue-specific 3xP3 promoter in separated but tightly linked expression cassettes, we targeted the ECFP nucleotide sequence for disruption. When supplying the Cas9 enzyme and two sgRNAs targeting different regions of the ECFP gene as in vitro transcribed mRNAs for germline transformation, we recovered four different G1 pools (5.5% knockout efficiency where individuals still expressed DsRed but no longer ECFP. PCR amplification, cloning, and sequencing of PCR amplicons revealed indels in the ECFP target gene ranging from 2-27 nucleotides. These results show for the first time that CRISPR/Cas9 mediated gene editing is achievable in Ae. aegypti, paving the way for further functional genomics related studies in this mosquito species.

Ecdysis period and rate deviations of dengue mosquito vector, Aedes aegypti reared in different artificial water-holding containers.

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Almanzor, Beatriz Louise J; Ho, Howell T; Carvajal, Thaddeus M

2016-03-01

Artificial water-holding containers (AWHCs) have been well-documented in many Aedes aegypti studies for dengue surveillance and developmental research. Hence, we investigated the role of different AHWCs on the development and ecdysis period of Ae. aegypti dengue vector, a container breeding mosquito. Nine types of AWHCs, namely glass, polystyrene foam, rubber, steel, porcelain, plastic, aluminum, clay and concrete, were chosen for the study. All AWHCs were subjected to the developmental assay for an observation period of 10 days. Regression and hazard analyses were employed to the developmental stages and the characteristics of the AWHCs. The observations revealed that Ae. aegypti development is fastest in glass and polystyrene containers while slowest in concrete containers. Moreover, pupal ecdysis appears to be the most affected by the characteristics of the AWHCs based on regression and hazard analyses. Characteristics of the container that can regulate water temperature seem to be the driving force with regards to the slow or fast development of Ae. aegypti, more notably in pupal ecdysis. The results of the study further strengthen our understanding on the dynamics of Ae. aegypti's developmental biology to different characteristics of artificial water containers. This, in turn, would aid in devising vector control strategies against dengue especially in endemic areas.

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

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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.

Application of wMelPop Wolbachia Strain to Crash Local Populations of Aedes aegypti.

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Scott A Ritchie

Full Text Available The endosymbiotic bacteria Wolbachia pipientis (wMel strain has been successfully established in several populations of Aedes aegypti, the primary dengue vector. The virulent Wolbachia strain wMelPop is known to cause several pathological impacts (increased egg mortality, life shortening, etc. reducing overall fitness in the mosquito Ae. aegypti. Increased egg mortality could substantially reduce egg banks in areas with a lengthy monsoonal dry season, and be employed to eliminate local populations. We tested this application under semi-field cage conditions. First, we determined that wMelPop infection significantly reduced the survival of desiccation-resistant eggs of the dengue vector Ae. aegypti, with shade and temperature having a significant impact; nearly all wMelPop-infected eggs failed to hatch after 6 and 10 weeks in summer and winter conditions, respectively. In laboratory selection experiments we found that egg desiccation resistance can be increased by selection, and that this effect of wMelPop infection is due to the nuclear background of the host rather than Wolbachia. We then conducted an invasion of wMelPop within a semi-field cage using sustained weekly releases of wMelPop infected mosquitoes, with fixation achieved after 9 weeks. The egg populations wMelPop infected and an uninfected control were then subjected to a simulated prolonged monsoonal dry season (2.5 months before flooding to induce hatching. The wMelPop infected eggs suffered significantly greater mortality than the controls, with only 0.67% and 4.35% of respective infected and uninfected eggs held in 99% shade hatching after 80 days. These studies suggest that wMelPop could be used to locally eliminate populations of Ae. aegypti that are exposed to prolonged dry conditions, particularly if combined with vector control.

Characteristics of Aedes aegypti adult mosquitoes in rural and urban areas of western and coastal Kenya

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Ndenga, Bryson Alberto; Mutuku, Francis Maluki; Ngugi, Harun Njenga; Mbakaya, Joel Omari; Aswani, Peter; Musunzaji, Peter Siema; Vulule, John; Mukoko, Dunstan; Kitron, Uriel; LaBeaud, Angelle Desiree

2017-01-01

Aedes aegypti is the main vector for yellow fever, dengue, chikungunya and Zika viruses. Recent outbreaks of dengue and chikungunya have been reported in Kenya. Presence and abundance of this vector is associated with the risk for the occurrence and transmission of these diseases. This study aimed to characterize the presence and abundance of Ae. aegypti adult mosquitoes from rural and urban sites in western and coastal regions of Kenya. Presence and abundance of Ae. aegypti adult mosquitoes were determined indoors and outdoors in two western (urban Kisumu and rural Chulaimbo) and two coastal (urban Ukunda and rural Msambweni) sites in Kenya. Sampling was performed using quarterly human landing catches, monthly Prokopack automated aspirators and monthly Biogents-sentinel traps. A total of 2,229 adult Ae. aegypti mosquitoes were collected: 785 (35.2%) by human landing catches, 459 (20.6%) by Prokopack aspiration and 985 (44.2%) by Biogents-sentinel traps. About three times as many Ae. aegypti mosquitoes were collected in urban than rural sites (1,650 versus 579). Comparable numbers were collected in western (1,196) and coastal (1,033) sites. Over 80% were collected outdoors through human landing catches and Prokopack aspiration. The probability of collecting Ae. aegypti mosquitoes by human landing catches was significantly higher in the afternoon than morning hours (Paegypti mosquitoes were collected using Prokopack aspiration outdoors than indoors (Paegypti bites was highest in urban areas, outdoors and in the afternoon hours. These characteristics have major implications for the possible transmission of arboviral diseases and for the planning of surveillance and control programs. PMID:29261766

Characterization and biotoxicity of Hypnea musciformis-synthesized silver nanoparticles as potential eco-friendly control tool against Aedes aegypti and Plutella xylostella.

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Roni, Mathath; Murugan, Kadarkarai; Panneerselvam, Chellasamy; Subramaniam, Jayapal; Nicoletti, Marcello; Madhiyazhagan, Pari; Dinesh, Devakumar; Suresh, Udaiyan; Khater, Hanem F; Wei, Hui; Canale, Angelo; Alarfaj, Abdullah A; Munusamy, Murugan A; Higuchi, Akon; Benelli, Giovanni

2015-11-01

Two of the most important challenges facing humanity in the 21st century comprise food production and disease control. Eco-friendly control tools against mosquito vectors and agricultural pests are urgently needed. Insecticidal products of marine origin have a huge potential to control these pests. In this research, we reported a single-step method to synthesize silver nanoparticles (AgNP) using the aqueous leaf extract of the seaweed Hypnea musciformis, a cheap, nontoxic and eco-friendly material, that worked as reducing and stabilizing agent during the biosynthesis. The formation of AgNP was confirmed by surface plasmon resonance band illustrated in UV-vis spectrophotometer. AgNP were characterized by FTIR, SEM, EDX and XRD analyses. AgNP were mostly spherical in shape, crystalline in nature, with face-centered cubic geometry, and their mean size was 40-65nm. Low doses of H. musciformis aqueous extract and seaweed-synthesized AgNP showed larvicidal and pupicidal toxicity against the dengue vector Aedes aegypti and the cabbage pest Plutella xylostella. The LC50 value of AgNP ranged from 18.14 to 38.23ppm for 1st instar larvae (L1) and pupae of A. aegypti, and from 24.5 to 38.23ppm for L1 and pupae of P. xylostella. Both H. musciformis extract and AgNP strongly reduced longevity and fecundity of A. aegypti and P. xylostella adults. This study adds knowledge on the toxicity of seaweed borne insecticides and green-synthesized AgNP against arthropods of medical and agricultural importance, allowing us to propose the tested products as effective candidates to develop newer and cheap pest control tools. Copyright © 2015 Elsevier Inc. All rights reserved.

Species Distribution Modelling of Aedes aegypti in two dengue-endemic regions of Pakistan.

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Fatima, Syeda Hira; Atif, Salman; Rasheed, Syed Basit; Zaidi, Farrah; Hussain, Ejaz

2016-03-01

Statistical tools are effectively used to determine the distribution of mosquitoes and to make ecological inferences about the vector-borne disease dynamics. In this study, we utilised species distribution models to understand spatial patterns of Aedes aegypti in two dengue-prevalent regions of Pakistan, Lahore and Swat. Species distribution models can potentially indicate the probability of suitability of Ae. aegypti once introduced to new regions like Swat, where invasion of this species is a recent phenomenon. The distribution of Ae. aegypti was determined by applying the MaxEnt algorithm on a set of potential environmental factors and species sample records. The ecological dependency of species on each environmental variable was analysed using response curves. We quantified the statistical performance of the models based on accuracy assessment and spatial predictions. Our results suggest that Ae. aegypti is widely distributed in Lahore. Human population density and urban infrastructure are primarily responsible for greater probability of mosquito occurrence in this region. In Swat, Ae. aegypti has clumped distribution, where urban patches provide refuge to the species in an otherwise hostile heterogeneous environment and road networks are assumed to have facilitated in passive-mediated dispersal of species. In Pakistan, Ae. aegypti is expanding its range northwards; this could be associated with rapid urbanisation, trade and travel. The main implication of this expansion is that more people are at risk of dengue fever in the northern highlands of Pakistan. © 2016 John Wiley & Sons Ltd.

Vector competence of populations of Aedes aegypti from three distinct cities in Kenya for chikungunya virus.

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Sheila B Agha

2017-08-01

Full Text Available In April, 2004, chikungunya virus (CHIKV re-emerged in Kenya and eventually spread to the islands in the Indian Ocean basin, South-East Asia, and the Americas. The virus, which is often associated with high levels of viremia in humans, is mostly transmitted by the urban vector, Aedes aegypti. The expansion of CHIKV presents a public health challenge both locally and internationally. In this study, we investigated the ability of Ae. aegypti mosquitoes from three distinct cities in Kenya; Mombasa (outbreak prone, Kisumu, and Nairobi (no documented outbreak to transmit CHIKV.Aedes aegypti mosquito populations were exposed to different doses of CHIKV (105.6-7.5 plaque-forming units[PFU]/ml in an infectious blood meal. Transmission was ascertained by collecting and testing saliva samples from individual mosquitoes at 5, 7, 9, and 14 days post exposure. Infection and dissemination were estimated by testing body and legs, respectively, for individual mosquitoes at selected days post exposure. Tissue culture assays were used to determine the presence of infectious viral particles in the body, leg, and saliva samples. The number of days post exposure had no effect on infection, dissemination, or transmission rates, but these rates increased with an increase in exposure dose in all three populations. Although the rates were highest in Ae. aegypti from Mombasa at titers ≥106.9 PFU/ml, the differences observed were not statistically significant (χ2 ≤ 1.04, DF = 1, P ≥ 0.31. Overall, about 71% of the infected mosquitoes developed a disseminated infection, of which 21% successfully transmitted the virus into a capillary tube, giving an estimated transmission rate of about 10% for mosquitoes that ingested ≥106.9 PFU/ml of CHIKV. All three populations of Ae. aegypti were infectious as early as 5-7 days post exposure. On average, viral dissemination only occurred when body titers were ≥104 PFU/ml in all populations.Populations of Ae. aegypti from

Vector competence of populations of Aedes aegypti from three distinct cities in Kenya for chikungunya virus.

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Agha, Sheila B; Chepkorir, Edith; Mulwa, Francis; Tigoi, Caroline; Arum, Samwel; Guarido, Milehna M; Ambala, Peris; Chelangat, Betty; Lutomiah, Joel; Tchouassi, David P; Turell, Michael J; Sang, Rosemary

2017-08-01

In April, 2004, chikungunya virus (CHIKV) re-emerged in Kenya and eventually spread to the islands in the Indian Ocean basin, South-East Asia, and the Americas. The virus, which is often associated with high levels of viremia in humans, is mostly transmitted by the urban vector, Aedes aegypti. The expansion of CHIKV presents a public health challenge both locally and internationally. In this study, we investigated the ability of Ae. aegypti mosquitoes from three distinct cities in Kenya; Mombasa (outbreak prone), Kisumu, and Nairobi (no documented outbreak) to transmit CHIKV. Aedes aegypti mosquito populations were exposed to different doses of CHIKV (105.6-7.5 plaque-forming units[PFU]/ml) in an infectious blood meal. Transmission was ascertained by collecting and testing saliva samples from individual mosquitoes at 5, 7, 9, and 14 days post exposure. Infection and dissemination were estimated by testing body and legs, respectively, for individual mosquitoes at selected days post exposure. Tissue culture assays were used to determine the presence of infectious viral particles in the body, leg, and saliva samples. The number of days post exposure had no effect on infection, dissemination, or transmission rates, but these rates increased with an increase in exposure dose in all three populations. Although the rates were highest in Ae. aegypti from Mombasa at titers ≥106.9 PFU/ml, the differences observed were not statistically significant (χ2 ≤ 1.04, DF = 1, P ≥ 0.31). Overall, about 71% of the infected mosquitoes developed a disseminated infection, of which 21% successfully transmitted the virus into a capillary tube, giving an estimated transmission rate of about 10% for mosquitoes that ingested ≥106.9 PFU/ml of CHIKV. All three populations of Ae. aegypti were infectious as early as 5-7 days post exposure. On average, viral dissemination only occurred when body titers were ≥104 PFU/ml in all populations. Populations of Ae. aegypti from Mombasa, Nairobi

Insecticide resistance and, efficacy of space spraying and larviciding in the control of dengue vectors Aedes aegypti and Aedes albopictus in Sri Lanka.

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Karunaratne, S H P P; Weeraratne, T C; Perera, M D B; Surendran, S N

2013-09-01

Unprecedented incidence of dengue has been recorded in Sri Lanka in recent times. Source reduction and use of insecticides in space spraying/fogging and larviciding, are the primary means of controlling the vector mosquitoes Aedes aegypti and Ae. albopictus in the island nation. A study was carried out to understand insecticide cross-resistance spectra and mechanisms of insecticide resistance of both these vectors from six administrative districts, i.e. Kandy, Kurunegala, Puttalam, Gampaha, Ratnapura and Jaffna, of Sri Lanka. Efficacy of the recommended dosages of frequently used insecticides in space spraying and larviciding in dengue vector control programmes was also tested. Insecticide bioassay results revealed that, in general, both mosquito species were highly resistant to DDT but susceptible to propoxur and malathion except Jaffna Ae. aegypti population. Moderate resistance to malathion shown by Jaffna Ae. aegypti population correlated with esterase and malathion carboxylesterase activities of the population. High levels of acetylcholinesterase (AChE) insensitivity in the absence of malathion and propoxur resistance may be due to non-synaptic forms of AChE proteins. Moderate pyrethroid resistance in the absence of high monooxygenase levels indicated the possible involvement of 'kdr' type resistance mechanism in Sri Lankan dengue vectors. Results of the space spraying experiments revealed that 100% mortality at a 10 m distance and >50% mortality at a 50 m distance can be achieved with malathion, pesguard and deltacide even in a ground with dense vegetation. Pesguard and deltacide spraying gave 100% mortality up to 50 m distance in open area and areas with little vegetation. Both species gave >50% mortalities for deltacide at a distance of 75 m in a dense vegetation area. Larval bioassays conducted in the laboratory showed that a 1 ppm temephos solution can maintain a larval mortality rate of 100% for ten months, and the mortality rate declined to 0% in the

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

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Three gustatory receptor neurons were characterized for contact chemoreceptive sensilla on the labella of female yellow fever mosquitoes, Aedes aegypti. The neuron with the smallest amplitude spike responded to the feeding deterrent, quinine, as well as DEET and other insect repellents. Two other ...

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

Ecological interactions in Aedes species on Reunion Island.

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Bagny Beilhe, L; Delatte, H; Juliano, S A; Fontenille, D; Quilici, S

2013-12-01

Two invasive, container-breeding mosquito species, Aedes aegypti (Stegomyia aegypti) and Aedes albopictus (Stegomyia albopicta) (Diptera: Culicidae), have different distribution patterns on Reunion Island. Aedes albopictus occurs in all areas and Ae. aegypti colonizes only some restricted areas already occupied by Ae. albopictus. This study investigates the abiotic and biotic ecological mechanisms that determine the distribution of Aedes species on Reunion Island. Life history traits (duration of immature stages, survivorship, fecundity, estimated finite rate of increase) in Ae. aegypti and Ae. albopictus were compared at different temperatures. These fitness measures were characterized in both species in response to competitive interactions among larvae. Aedes aegypti was drastically affected by temperature, performing well only at around 25 °C, at which it achieved its highest survivorship and greatest estimated rate of increase. The narrow distribution of this species in the field on Reunion Island may thus relate to its poor ability to cope with unfavourable temperatures. Aedes aegypti was also more negatively affected by high population densities and to some extent by interactions with Ae. albopictus, particularly in the context of limited food supplies. Aedes albopictus exhibited better population performance across a range of environmental conditions. Its ecological plasticity and its superior competitive ability relative to its congener may further enhance its invasion success on Reunion Island. © 2012 The Royal Entomological Society.

Control of Aedes aegypti Breeding: A Novel Intervention for Prevention and Control of Dengue in an Endemic Zone of Delhi, India.

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B N Nagpal

Full Text Available The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December-May months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June-November. The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI, house index (HI, pupal index (PI and breteau index (BI.A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities.Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05. In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (p<0.05 between the study group and control group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as

Larvicidal activity against Aedes aegypti of Foeniculum vulgare essential oils from Portugal and Cape Verde.

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Rocha, Diara Kady; Matosc, Olivia; Novoa, Maria Teresa; Figueiredo, Ana Cristina; Delgado, Manuel; Moiteiro, Cristina

2015-04-01

Dengue is a potentially fatal mosquito-borne infection with 50 million cases per year and 2.5 billion people vulnerable to the disease. This major public health problem has recurrent epidemics in Latin America and occurred recently in Cape Verde and Madeira Island. The lack of anti-viral treatment or vaccine makes the control of mosquito vectors a high option to prevent virus transmission. Essential oil (EO) constituents can affect insect's behaviour, being potentially effective in pest control. The present study evaluated the potential use of Foenicultm vulgare (fennel) EO in the control of the dengue vector Aedes aegypti. EOs isolated from fennel aerial parts collected in Cape Verde and from a commercial fennel EO of Portugal were analysed by NMR, GC and GC-MS. trans-Anethole (32 and 30%, respectively), limonene (28 and 18%, respectively) and fenchone (10% in both cases) were the main compounds identified in the EOs isolated from fennel from Cape Verde and Portugal, respectively. The larvicidal activity of the EOs and its major constituents were evaluated, using WHO procedures, against third instar larvae ofAe. aegypti for 24 h. Pure compounds, such as limonene isomers, were also assayed. The lethal concentrations LC50, C90 and LC99 were determined by probit analysis using mortality rates of bioassays. A 99% mortality of Ae. aegypti larvae was estimated at 37.1 and 52.4 µL L-1 of fennel EOs from Cape Verde and Portugal, respectively. Bioassays showed that fennel EOs from both countries displayed strong larvicidal effect against Ae. aegypti, the Cape Verde EO being as active as one of its major constituents, (-)-limonene.

The Impact of Selection with Diflubenzuron, a Chitin Synthesis Inhibitor, on the Fitness of Two Brazilian Aedes aegypti Field Populations

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Belinato, Thiago Affonso; Valle, Denise

2015-01-01

Several Aedes aegypti field populations are resistant to neurotoxic insecticides, mainly organophoshates and pyrethroids, which are extensively used as larvicides and adulticides, respectively. Diflubenzuron (DFB), a chitin synthesis inhibitor (CSI), was recently approved for use in drinking water, and is presently employed in Brazil for Ae. aegypti control, against populations resistant to the organophosphate temephos. However, tests of DFB efficacy against field Ae. aegypti populations are lacking. In addition, information regarding the dynamics of CSI resistance, and characterization of any potential fitness effects that may arise in conjunction with resistance are essential for new Ae. aegypti control strategies. Here, the efficacy of DFB was evaluated for two Brazilian Ae. aegypti populations known to be resistant to both temephos and the pyrethroid deltamethrin. Laboratory selection for DFB resistance was then performed over six or seven generations, using a fixed dose of insecticide that inhibited 80% of adult emergence in the first generation. The selection process was stopped when adult emergence in the diflubenzuron-treated groups was equivalent to that of the control groups, kept without insecticide. Diflubenzuron was effective against the two Ae. aegypti field populations evaluated, regardless of their resistance level to neurotoxic insecticides. However, only a few generations of DFB selection were sufficient to change the susceptible status of both populations to this compound. Several aspects of mosquito biology were affected in both selected populations, indicating that diflubenzuron resistance acquisition is associated with a fitness cost. We believe that these results can significantly contribute to the design of control strategies involving the use of insect growth regulators. PMID:26107715

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

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

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,

Voltage-gated sodium channel polymorphism and metabolic resistance in pyrethroid-resistant Aedes aegypti from Brazil.

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Martins, Ademir Jesus; Lins, Rachel Mazzei Moura de Andrade; Linss, Jutta Gerlinde Birgitt; Peixoto, Alexandre Afranio; Valle, Denise

2009-07-01

The nature of pyrethroid resistance in Aedes aegypti Brazilian populations was investigated. Quantification of enzymes related to metabolic resistance in two distinct populations, located in the Northeast and Southeast regions, revealed increases in Glutathione-S-transferase (GST) and Esterase levels. Additionally, polymorphism was found in the IIS6 region of Ae. aegypti voltage-gated sodium channel (AaNa(V)), the pyrethroid target site. Sequences were classified in two haplotype groups, A and B, according to the size of the intron in that region. Rockefeller, a susceptible control lineage, contains only B sequences. In field populations, some A sequences present a substitution in the 1011 site (Ile/Met). When resistant and susceptible individuals were compared, the frequency of both A (with the Met mutation) and B sequences were slightly increased in resistant specimens. The involvement of the AaNa(V) polymorphism in pyrethroid resistance and the metabolic mechanisms that lead to potential cross-resistance between organophosphate and pyrethroids are discussed.

Genetic differentiation in populations of Aedes aegypti (Diptera, Culicidae dengue vector from the Brazilian state of Maranhão

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Andrelina Alves de Sousa

Full Text Available ABSTRACT Aedes (Stegomyia aegypti is the vector responsible for the transmission of the viruses that cause zika, yellow and chikungunya fevers, the four dengue fever serotypes (DENV - 1, 2, 3, 4, and hemorrhagic dengue fever in tropical and subtropical regions around the world. The present study investigated the genetic differentiation of the 15 populations of this vector in the Brazilian state of Maranhão, based on the mitochondrial ND4 marker. A total of 177 sequences were obtained for Aedes aegypti, with a fragment of 337 bps, 15 haplotypes, 15 polymorphics sites, haplotype diversity of h = 0.6938, and nucleotide diversity of π = 0.01486. The neutrality tests (D and Fs were not significant. The AMOVA revealed that most of the variation (58.47% was found within populations, with FST = 0.41533 (p < 0.05. Possible isolation by distance was tested and a significant correlation coefficient (r = 0.3486; p = 0.0040 was found using the Mantel test. The phylogenetic relationships among the 15 haplotypes indicated the existence of two distinct clades. This finding, together with the population parameters, was consistent with a pattern of genetic structuring that underpinned the genetic differentiation of the study populations in Maranhão, and was characterized by the presence of distinct lineages of Aedes aegypti.

Allergens involved in the cross-reactivity of Aedes aegypti with other arthropods.

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Cantillo, Jose Fernando; Puerta, Leonardo; Lafosse-Marin, Sylvie; Subiza, Jose Luis; Caraballo, Luis; Fernandez-Caldas, Enrique

2017-06-01

Cross-reactivity between Aedes aegypti and mites, cockroaches, and shrimp has been previously suggested, but the involved molecular components have not been fully described. To evaluate the cross-reactivity between A aegypti and other arthropods. Thirty-four serum samples from patients with asthma and/or allergic rhinitis were selected, and specific IgE to A aegypti, Dermatophagoides pteronyssinus, Dermatophagoides farinae, Blomia tropicalis, Periplaneta americana. and Litopenaeus vannamei was measured by enzyme-linked immunosorbent assay. Cross-reactivity was investigated using pooled serum samples from allergic patients, allergenic extracts, and the recombinant tropomyosins (Aed a 10.0201, Der p 10, Blo t 10, Lit v 1, and Per a 7). Four IgE reactive bands were further characterized by matrix-assisted laser desorption/ionization tandem time of flight. Frequency of positive IgE reactivity was 82.35% to at least one mite species, 64.7% to A aegypti, 29.4% to P americana, and 23.5% to L vannamei. The highest IgE cross-reactivity was seen between A aegypti and D pteronyssinus (96.6%) followed by L vannamei (95.4%), B tropicalis (84.4%), and P americana (75.4%). Recombinant tropomyosins from mites, cockroach, or shrimp inhibited the IgE reactivity to the mosquito at a lower extent than the extracts from these arthropods. Several bands of A aegypti cross-reacted with arthropod extracts, and 4 of them were identified as odorant binding protein, mitochondrial cytochrome C, peptidyl-prolyl cis-trans isomerase, and protein with hypothetical magnesium ion binding function. We identified 4 novel cross-reactive allergens in A aegypti allergenic extract. These molecules could influence the manifestation of allergy to environmental allergens in the tropics. Copyright © 2017 American College of Allergy, Asthma & Immunology. Published by Elsevier Inc. All rights reserved.

Ecological studies on the breeding of Aedes aegypti and other mosquitos in shells of the giant African snail Achatina fulica

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Trpis, Milan

1973-01-01

The breeding of larvae of Aedes aegypti, Aedes simpsoni, and Eretmapodites quinquevittatus in empty shells of Achatina fulica was studied in the coastal zone of Dar es Salaam, Tanzania. The average density of shells was estimated to be 228 per ha. From 11 to 35% were positive for mosquito larvae. A. aegypti were found in 82-84% of positive shells; A. simpsoni in 8-13%. On Msasani peninsula, during the 3-month rainy season April—June 1970, the larval density of A. aegypti in shells was estimated at 1 100 per ha, that of A. simpsoni and E. quinquevittatus being estimated at 60 and 280 larvae per ha, respectively. Empty shells of A. fulica may contain up to 250 ml of water (average: 56.5 ml). The number of larvae per shell varies from 1 to 35 (average: 8.4) and it was estimated that, depending on the availability of food, and other factors, approximately 10 ml of water are required per larva. Viable eggs of A. aegypti were still to be found in 4% of the shells at the end of the dry season. PMID:4148745

Dengue viruses binding proteins from Aedes aegypti and Aedes polynesiensis salivary glands

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Cao-Lormeau Van-Mai

2009-03-01

Full Text Available Abstract Dengue virus (DENV, the etiological agent of dengue fever, is transmitted to the human host during blood uptake by an infective mosquito. Infection of vector salivary glands and further injection of infectious saliva into the human host are key events of the DENV transmission cycle. However, the molecular mechanisms of DENV entry into the mosquito salivary glands have not been clearly identified. Otherwise, although it was demonstrated for other vector-transmitted pathogens that insect salivary components may interact with host immune agents and impact the establishment of infection, the role of mosquito saliva on DENV infection in human has been only poorly documented. To identify salivary gland molecules which might interact with DENV at these key steps of transmission cycle, we investigated the presence of proteins able to bind DENV in salivary gland extracts (SGE from two mosquito species. Using virus overlay protein binding assay, we detected several proteins able to bind DENV in SGE from Aedes aegypti (L. and Aedes polynesiensis (Marks. The present findings pave the way for the identification of proteins mediating DENV attachment or entry into mosquito salivary glands, and of saliva-secreted proteins those might be bound to the virus at the earliest step of human infection. The present findings might contribute to the identification of new targets for anti-dengue strategies.

Repellent activity of Cnidoscolus phyllacanthus Mart. and Ricinus communis L. extracts against Aedes aegypti L. oviposition behavior

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Lafayette Pereira Candido

2015-12-01

Full Text Available Female Aedes aegypti lay their eggs on nearly any moist substrate. Methods with potential to repel oviposition may reduce infestation, thereby contributing to control of epidemics. We evaluated the influence of Cnidoscolus phyllacanthus and Ricinus communis plant extracts on the oviposition behavior of A. aegypti. Lethal concentrations were first determined in experiments with larvae after 24 h of exposure, after which LC50 and LC90 were used to test oviposition repellency. The experiment consisted of an oviposition preference test based multiple-choice and no-choice assays. The Oviposition Activity Indices (OAIs from the multiple-choice test using both R. communis and C. phyllacanthus were negative, suggesting oviposition repellent and deterrent activity. The LC90 of both plant extracts deterred oviposition by this vector, as demonstrated by an OAI = value of -1. In the choice study, mean oviposition values were significantly different between R. communis and C. phyllacanthus. In the absence of choice, mosquitoes laid eggs independent of the substrate. In conclusion, our OAI values indicate that all substrates used repelled oviposition by A. aegypti.

Control of Aedes aegypti Breeding: A Novel Intervention for Prevention and Control of Dengue in an Endemic Zone of Delhi, India.

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Nagpal, B N; Gupta, Sanjeev Kumar; Shamim, Arshad; Vikram, Kumar; Srivastava, Aruna; Tuli, N R; Saxena, Rekha; Singh, Himmat; Singh, V P; Bhagat, V N; Yadav, N K; Valecha, Neena

2016-01-01

The study is based on hypothesis that whether continuous entomological surveillance of Ae. aegypti and simultaneous appropriate interventions in key containers during non-transmission (December-May) months would have any impact on breeding of Aedes and dengue cases during the following transmission months (June-November). The impact of the surveillance and intervention measures undertaken during non-transmission months were assessed by entomological indicators namely container index (CI), house index (HI), pupal index (PI) and breteau index (BI). A total of 28 localities of West Zone of Delhi with persistent dengue endemicity were selected for the study. Out of these localities, 20 were included in study group while other 8 localities were in control group. IEC and various Aedes breeding control activities were carried out in study group in both non-transmission and transmission season whereas control group did not have any such interventions during non-transmission months as per guidelines of MCD. These activities were undertaken by a team of investigators from NIMR and SDMC, Delhi. In control group, investigators from NIMR carried out surveillance activity to monitor the breeding of Aedes mosquito in localities. Comparison of baseline data revealed that all indices in control and study group of localities were comparable and statistically non-significant (p>0.05). In both study and control groups, indices were calculated after pooling data on seasonal basis, i.e., transmission and non-transmission months for both years. The test of significance conducted on all the four indices, i.e., HI, PI, CI, and BI, revealed a significant difference (pcontrol group during transmission and non-transmission months except in HI. Due to consistent intervention measures undertaken in non-transmission months in study group, reduction in CI, HI, BI and PI was observed 63%, 62%, 64% and 99% respectively during transmission months as compared to control group where increase of 59

The effectiveness of fixative addition on Zodia (Evodia suaveolens S. and rosemary (Rosmarinus officinalis l. gel against Aedes aegypti

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Mutiara Widawati

2014-02-01

fixative material (patchouli oil on Rosemary and Zodia repellent. Methods:This was an experimental study using gel made from essential oil of Rosemary flowers and Zodia leaves with concentrations of 0.1%, 0.5 %, 1 %, 2 %, 4 %, respectively. Control (+ group used N, N-diethyl-3 (methylbenzamide (DEET on the arms, while control (- group were arms with no treatment.The repellent was tested on the arms of trained volunteers, which were then observed every hour for six hours. The protective effectiveness was satisfactory if ≥90%. Results:Addition of fixative material increased the durability of repellent, starting from concentration of 2% for Rosemary and concentration of 4% for Zodia. The protective effectiveness was 90% for more than 6 hours. Conclusion:The modified gel of Zodia and Rosemary proved to be a potential repellent against Aedes aegyptimosquitos. (Health Science Indones 2013;2:103-6Key words: Aedes aegypti, Evodia suaveolens S., repellent effectiveness, Rosmarinus officinalis L.

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

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Claudia Andrea Núñez

2016-06-01

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

The correlation between temperature and humidity with the population density of Aedes aegypti as dengue fever’s vector

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Sintorini, M. M.

2018-01-01

The weather change in South East Asia have triggered the increase of dengue fever illness in Indonesia. Jakarta has been declared as one of dengue fever endemic region. This research aim to gain the dynamic of dengue fever incidents related to temperature, humidity and the population density of Aedes aegypti. This research implementated Design of Ecology Study. The samples were collected from April 2015 to March 2016, from houses located in the suburbs i.e. Pasar Minggu, Ciracas, Sunter Agung, Palmerah and Bendungan Hilir. The sampling based on Sampling Design Cluster and each suburb represents 153 samples. The research shows correlation between temperature (p value 0.000) and humidity (p value 0,000) with Aedes aegypti as dengue fever’s Vector. Therefore, an early warning system should be developed based on environmental factors to anticipate the spread of dengue fever.

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

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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.

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

Directory of Open Access Journals (Sweden)

Andrew F van den Hurk

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

Bioassay-guided isolation and identification of Aedes aegypti larvicidal and biting deterrent compounds from Veratrum lobelianum

Science.gov (United States)

An ethanol extract from Veratrum lobelianum Bernh. rhizomes was evaluated for biting deterrent and larvicidal activity against Aedes aegypti. V. lobelianum extract showed larvicidal activity with LC50 values of 11.79 ppm and 89.9 ppm against 1st and 4th instar larvae, respectively, at 24 h post-trea...

Aedes aegypti breeding ecology in Guerrero: cross-sectional study of mosquito breeding sites from the baseline for the Camino Verde trial in Mexico

OpenAIRE

Arcadio Morales-Pérez; Elizabeth Nava-Aguilera; Alejandro Balanzar-Martínez; Antonio Juan Cortés-Guzmán; David Gasga-Salinas; Irma Esther Rodríguez-Ramos; Alba Meneses-Rentería; Sergio Paredes-Solís; José Legorreta-Soberanis; Felipe Gil Armendariz-Valle; Robert J. Ledogar; Anne Cockcroft; Neil Andersson

2017-01-01

Abstract Background Understanding the breeding patterns of Aedes aegypti in households and the factors associated with infestation are important for implementing vector control. The baseline survey of a cluster randomised controlled trial of community mobilisation for dengue prevention in Mexico and Nicaragua collected information about the containers that are the main breeding sites, identified possible actions to reduce breeding, and examined factors associated with household infestation. T...

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

Directory of Open Access Journals (Sweden)

Mateus Chediak

2016-01-01

Full Text Available The organophosphate temephos has been the main insecticide used against larvae of the dengue and yellow fever mosquito (Aedes aegypti in Brazil since the mid-1980s. Reports of resistance date back to 1995; however, no systematic reports of widespread temephos resistance have occurred to date. As resistance investigation is paramount for strategic decision-making by health officials, our objective here was to investigate the spatial and temporal spread of temephos resistance in Ae. aegypti in Brazil for the last 12 years using discriminating temephos concentrations and the bioassay protocols of the World Health Organization. The mortality results obtained were subjected to spatial analysis for distance interpolation using semi-variance models to generate maps that depict the spread of temephos resistance in Brazil since 1999. The problem has been expanding. Since 2002-2003, approximately half the country has exhibited mosquito populations resistant to temephos. The frequency of temephos resistance and, likely, control failures, which start when the insecticide mortality level drops below 80%, has increased even further since 2004. Few parts of Brazil are able to achieve the target 80% efficacy threshold by 2010/2011, resulting in a significant risk of control failure by temephos in most of the country. The widespread resistance to temephos in Brazilian Ae. aegypti populations greatly compromise effective mosquito control efforts using this insecticide and indicates the urgent need to identify alternative insecticides aided by the preventive elimination of potential mosquito breeding sites.

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.

Transcriptional Analysis of Four Family 4 P450s in a Puerto Rico Strain of Aedes aegypti (Diptera: Culicidae) Compared With an Orlando Strain and Their Possible Functional Roles in Permethrin Resistance

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2014-05-01

MOLECULAR BIOLOGY/GENOMICS Transcriptional Analysis of Four Family 4 P450s in a Puerto Rico Strain of Aedes aegypti (Diptera: Culicidae) Compared...10.1603/ME13228 ABSTRACT A Þeld strain of Aedes aegypti (L.) was collected from Puerto Rico in October 2008. Based onLD50 values by topical application...important role in cytochrome P450-mediated resistance to permethrin. KEY WORDS Aedes aegytpi, permethrin, resistance, cytochrome P450, detoxiÞcation The

The Influence of Dengue Virus Serotype-2 Infection on Aedes aegypti (Diptera: Culicidae) Motivation and Avidity to Blood Feed

OpenAIRE

Maciel-de-Freitas, Rafael; Sylvestre, Gabriel; Gandini, Mariana; Koella, Jacob C.

2013-01-01

BACKGROUND: Dengue virus (DENV) is transmitted by Aedes aegypti, a species that lives in close association with human dwellings. The behavior of DENV-infected mosquitoes needs further investigation, especially regarding the potential influence of DENV on mosquito biting motivation and avidity. METHODOLOGY/PRINCIPAL FINDINGS: We orally challenged 4-5 day-old Ae. aegypti females with a low passage DENV serotype -2 (DENV-2) to test whether the virus influences motivation to feed (the likelihood ...

Characterizing the Aedes aegypti Population in a Vietnamese Village in Preparation for a Wolbachia-Based Mosquito Control Strategy to Eliminate Dengue

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Jeffery, Jason A. L.; Thi Yen, Nguyen; Nam, Vu Sinh; Nghia, Le Trung; Hoffmann, Ary A.; Kay, Brian H.; Ryan, Peter A.

2009-01-01

Background A life-shortening strain of the obligate intracellular bacteria Wolbachia, called wMelPop, is seen as a promising new tool for the control of Aedes aegypti. However, developing a vector control strategy based on the release of mosquitoes transinfected with wMelPop requires detailed knowledge of the demographics of the target population. Methodology/Principal Findings In Tri Nguyen village (611 households) on Hon Mieu Island in central Vietnam, we conducted nine quantitative entomologic surveys over 14 months to determine if Ae. aegypti populations were spatially and temporally homogenous, and to estimate population size. There was no obvious relationship between mosquito (larval, pupal or adult) abundance and temperature and rainfall, and no area of the village supported consistently high numbers of mosquitoes. In almost all surveys, key premises produced high numbers of Ae. aegypti. However, these premises were not consistent between surveys. For an intervention based on a single release of wMelPop-infected Ae. aegypti, release ratios of infected to uninfected adult mosquitoes of all age classes are estimated to be 1.8–6.7∶1 for gravid females (and similarly aged males) or teneral adults, respectively. We calculated that adult female mosquito abundance in Tri Nguyen village could range from 1.1 to 43.3 individuals of all age classes per house. Thus, an intervention could require the release of 2–78 wMelPop-infected gravid females and similarly aged males per house, or 7–290 infected teneral female and male mosquitoes per house. Conclusions/Significance Given the variability we encountered, this study highlights the importance of multiple entomologic surveys when evaluating the spatial structure of a vector population or estimating population size. If a single release of wMelPop-infected Ae. aegypti were to occur when wild Ae. aegypti abundance was at its maximum, a preintervention control program would be necessary to ensure that there was no