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

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

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

Waco strain at both 14 and 21 days post-infection, the infection rate dropped from 38.9% to 5.6% between those two days in the case of the WB1 strain. Wolbachia-induced inhibition of DENV infection provides us with a bonus for using this endosymbiont to block dengue transmission in the mosquito. The anti-dengue effect of this endosymbiont is not solely dependent on the effector transgenes carried by Wolbachia. Therefore, the main requirement for the effector transgenes is merely to eliminate any dengue viruses that survive the Wolbachia-induced suppression. This added advantage might enhance the efficiency of an anti-dengue effector, because a lesser dose of effector would be necessary when it is expressed by and delivered from Wolbachia than if it were to function alone. The anti- dengue effect of Wolbachia can also reduce concerns over losing the link between antipathogen and the transgene driver, because Wolbachia alone can confer resistance to DENV in mosquitoes. Also, Wolbachia may be able to be used directly to blocking dengue transmission without linkage to an anti-dengue gene. This strategy will, however, require a better understanding of the mechanism underlying the dengue inhibition effect conferred by Wolbachia. By improving the efficiency of this inhibition mechanism, a complete blockade of dengue transmission could potentially be achieved. Finally, although DENV was still present in the proboscis of some WB1 mosquitoes in our study, the titer was 12 times lower than in the Waco strain. It will be interesting to know whether this level is below the threshold viral titer that is required to cause infection in humans. As has been reported in Drosophila [12,13], we observed that wAlbB could increase the survival rate of the dengue-infected mosquitoes. Such an increase in survival was not observed when WB1 were fed uninfected blood. However, in another study, when Ae. albopictus were fed with blood without DENV, Wolbachia (a superinfection of wAlbA and wAlbB, referred as wAlbA&B) was reported to provide a fitness advantage, including an increase in the mosquitoes’ longevity [21]. This difference in the observed results might reflect differences in experimental design, infection status, or mosquito species. Thus far, Wolbachia has been reported to affect the life span of its mosquito hosts in two different directions, with the longevity reduced or increased by wMelPop or wAlbA&B, respectively [9,10,21]. Although the underlying mechanism is still unclear, it is possible that Wolbachia interacts with certain biological pathways, such as the insulin signaling pathway [22], which can influence the host’s life span.
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The Aedes aegypti toll pathway controls dengue virus infection.

The Aedes aegypti toll pathway controls dengue virus infection.

The Toll pathway is involved in the anti-dengue defense The prominent activation of the Toll pathway (Rel1)-regulated genes in response to dengue infection strongly suggested that this pathway is involved in the mosquito’s anti-dengue defense. To investigate this hypothesis, we tested the effect of both Cactus and Caspar gene silencing on virus infection in the midgut and carcass at 7 days after an infectious blood meal. This cactus gene silencing reduced the extent of dengue infection in the midgut by 4.0-fold (P,0.05), while Caspar gene silencing had no effect on viral infection when compared to the GFP dsRNA control (Fig. 4). The lower viral loads in the midguts of mosquitoes treated with Cactus dsRNA were also confirmed by IFA assay (Fig. 4). To provide further evidence for Toll pathway implication in controlling dengue virus infection, we assessed whether loss of Toll pathway activation will lead to an increase in virus load. The Toll pathway was inactivated by silencing the MYD88 factor prior to dengue virus titer determination [33]. This resulted in an increase of the virus load by 2.7 times compared to the GFP dsRNA control (P,0.001). Infection levels in the carcass tissue were generally very low for all treatment groups, and there were no significant differences between groups. These results point to a significant role for the Toll pathway in the anti-dengue defense in the midgut tissue and they are similar to those reported for D. melanogaster, in which the Toll pathway, but not the Imd pathway, has been shown to be involved in limiting X-virus infection. Together with the gene expression data discussed above, our results suggest that the infection of mosquitoes with dengue virus induces the Toll pathway, which then exerts an anti-dengue effect.
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Application of wMelPop Wolbachia Strain to Crash Local Populations of Aedes aegypti.

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

The use of wMelPop to eliminate local populations of Ae. aegypti will likely be limited by several constraints. It took 16 weeks of releases, with 2 cycles of vector control, to fix wMelPop in a small semi-field cage. Thus, releases without vector control, population suppression or another mechanism to assist invasion like the use of insecticide resistance are likely to be chal- lenging [36]. The site will likely need to be isolated to avoid rapid re-infestation from adjacent areas, and will likely need to be relatively small, such as an isolated township [26]. Also the locale must have a prolonged dry period to facilitate egg death, as modelled in Rasic et al. [26]. Indeed, there were 4 viable infected eggs (3 from a bucket, and 1 from a PPB) after 80 days in the full shade cohort, suggesting that wMelPop may persist at a very low level requiring addi- tional vector control for elimination. Finally, candidate areas need to be focused on the elimi- nation of Ae. aegypti, rather than simply a reduction of dengue risk, which will be more easily achieved by releases of wMel rather than wMelPop. The data generated from this study could be used to identify geographic areas through modelling where the use of virulent Wolbachia and vector control for population suppression would be most effective.
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Native Wolbachia from Aedes albopictus Blocks Chikungunya Virus Infection In Cellulo.

Native Wolbachia from Aedes albopictus Blocks Chikungunya Virus Infection In Cellulo.

Wolbachia, a widespread endosymbiont of terrestrial arthropods, can protect its host against viral and parasitic infections, a phenotype called "pathogen blocking". However, in some cases Wolbachia may have no effect or even enhance pathogen infection, depending on the host-Wolbachia-pathogen combination. The tiger mosquito Aedes albopictus is natu- rally infected by two strains of Wolbachia, wAlbA and wAlbB, and is a competent vector for different arboviruses such as dengue virus (DENV) and Chikungunya virus (CHIKV). Inter- estingly, it was shown in some cases that Ae. albopictus native Wolbachia strains are able to inhibit DENV transmission by limiting viral replication in salivary glands, but no such impact was measured on CHIKV replication in vivo. To better understand the Wolbachia/ CHIKV/Ae. albopictus interaction, we generated a cellular model using Ae. albopictus derived C6/36 cells that we infected with the wAlbB strain. Our results indicate that CHIKV infection is negatively impacted at both RNA replication and virus assembly/secretion steps in presence of wAlbB. Using FISH, we observed CHIKV and wAlbB in the same mosquito cells, indicating that the virus is still able to enter the cell in the presence of the bacterium. Further work is needed to decipher molecular pathways involved in Wolbachia-CHIKV inter- action at the cellular level, but this cellular model can be a useful tool to study the mecha- nism behind virus blocking phenotype induced by Wolbachia. More broadly, this underlines that despite Wolbachia antiviral potential other complex interactions occur in vivo to deter- mine mosquito vector competence in Ae. albopictus.
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Dengue no Brasil: abordagem geográfica na escala nacional

Dengue no Brasil: abordagem geográfica na escala nacional

As inúmeras transformações socioespaciais advindas da expansão e consolidação desigual do Meio Técnico-Científico-Informacional desde o fim da Segunda Guerra Mundial tiveram efeito em todo o globo. Devido a essas transformações, o dengue se modificou, adaptando-se a esse novo meio. O aumento do número e do tamanho das cidades, que ocorreu de forma perversa, o rápido e intenso fluxo de pessoas e materiais e a degradação da saúde pública em todo mundo contribuíram para que essa doença se tornasse uma pandemia global em meados do século XX. No Brasil, ela retornou após 60 anos depois de erradicada, causando muitos problemas e a morte de várias pessoas. A hipótese do trabalho é que a distribuição e a incidência do dengue no Brasil foram, e estão sendo afetadas pelas transformações socioespaciais advindas da consolidação desigual do meio atual, que propiciou sua reemergência no território nacional e a emergência do dengue hemorrágico como um grande problema de saúde pública. O objetivo principal constitui em analisar a reemergência do dengue no Brasil e sua relação com as mudanças socioespaciais advindas da expansão desigual do Meio Técnico-Científico-Informacional e os processos de globalização no país, comparando diversas escalas geográficas. Também foi analisado os principais determinantes em escala nacional, bem como uma proposta de tipologia do dengue no Brasil, elecando as principais variáveis explicativas da doença no território.
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Differential susceptibility of two field aedes aegypti populations to a low infectious dose of dengue virus.

Differential susceptibility of two field aedes aegypti populations to a low infectious dose of dengue virus.

response (i.e., mosquito infection rates ,50%) has generally not been examined, perhaps because vector-virus interaction studies need to maximize the number of infected mosquitoes. Gaining a better understanding of the lower part of the dose-response to DENV is epidemiologically important for at least three reasons. First, epidemic DENV transmission is not always associated with high human viremias [15,16]. Second, even when peak viremia is high, there are periods of low viremia during the onset and resolution of the viremic period that may contribute to human-to- mosquito DENV transmission. Third, understanding infectious- ness to mosquitoes at low viremia levels is important to quantify the potential contribution of people with mild or clinically inapparent infections to overall DENV transmission. Inapparent and mild DENV infections are assumed to be associated with lower viremia levels by extrapolating the positive relationship observed between viremia and disease severity in symptomatic human cases [7,17–19]. The contribution of mild human infections to DENV transmission may be epidemiologically underappreciated because they have not been studied and they tend to outnumber the more severe infections that make up the bulk of the cases detected and studied by public health systems [1,20,21].
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Aedes aegypti, dengue y fiebre amarilla

Aedes aegypti, dengue y fiebre amarilla

todos los países, con el fm de mantenerlos en conocimiento del comportamiento de la enfermedad. Es pertinente señalar que la OPS ha proporcionado consultas epidemio[r]

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Serratia odorifera a midgut inhabitant of Aedes aegypti mosquito enhances its susceptibility to dengue-2 virus.

Serratia odorifera a midgut inhabitant of Aedes aegypti mosquito enhances its susceptibility to dengue-2 virus.

Oral feeding of mosquitoes. The virus infection assays were performed with 4–6 days old Ae. aegypti females. The white leg horn fowls were bled through the heart, and the blood was defibrinated using glass beads and was used for further feeding experiments. The mosquitoes were allowed to feed for one hour through a goat intestine membrane covering the base of a glass feeder that carried the blood-virus or blood-virus-bacteria mixture maintained at 37 uC. For an individual experiment, the infectious meal was given to three groups; Group 1: One mL of blood mixture containing the 250 m l dengue virus (5610 5 PFU/mL) [Total n = 78, about 25–30 females/experiment in three indepen- dent experiments], Group 2: One ml of blood mixture containing the 250 m l dengue virus (5610 5 PFU/mL) along with 250 m l of Serratia odorifera (1.2610 5 CFU/mL) [Total n = 158, about 35–40 females/experiment in four independent experiments] and Group 3: One mL of blood mixture containing the 250 m l dengue virus (5 610 5 PFU/mL) along with 250 m l of Microbacterium oxydans (1.2610 5 CFU/mL) [Total n = 87, about 25–30 females/experi- ment in three independent experiments]. Fully engorged females were transferred to small containers and were maintained with 10% glucose at 2861uC for 14 days. To evaluate the infection and dissemination rate and in turn vector competence on 14 PID, surviving females were sacrificed by transferring them to 280uC and tested for the presence of dengue-2 antigens in the head squashes by immunofluorescence assay (IFA). Three such inde- pendent experiments were carried out for evaluating the data. The DENV-2 titer in mosquitoes at 0 hour was determined by plaque assay (n = 10 for each group). Similarly, the dengue-2 titer in individual carcass of infected female was determined using a plaque assay. The average of virus titers from 24 carcasses of each group was determined and used for comparative analysis.
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Controlling the Vector Aedes Aegypti and Handling Dengue Fever Bearing Patients          /          Controle do Vetor Aedes Aegypti e Manejo dos Pacientes com Dengue

Controlling the Vector Aedes Aegypti and Handling Dengue Fever Bearing Patients / Controle do Vetor Aedes Aegypti e Manejo dos Pacientes com Dengue

The health professionals who participated in this study work in Primary Care and did an expressive number of visits in an epidemic period, which allowed them to appropriate the symptoms and forms of dengue. They used the warning signs indicated by the Ministry of Health to refer the patient to the hospital. Among the main warning signs for severe dengue, the following stand out: lethargy/ agitation, major hemorrhages, persistent vomiting, severe and continuous abdominal pain, increased hematocrit and/ or a rapid decrease in platelet count, hypotension and/or fainting.
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Immuno-dot blot para detecção do vírus da dengue em Aedes aegypti e em Aedes albopictus

Immuno-dot blot para detecção do vírus da dengue em Aedes aegypti e em Aedes albopictus

Segundo a Organização Mundial de Saúde (OMS), a dengue acomete anualmente 100 milhões de pessoas em 100 países de todos os continentes, exceto a Europa. Ainda segundo a OMS, cerca de 550 mil doentes necessitam anualmente de hospitalização e 20 mil morrem em conseqüência da dengue (MINISTÉRIO DA SAÚDE, 2002). A dengue é hoje a mais importante arbovirose que afeta o homem e constitui sério problema de saúde pública no mundo, especialmente em países tropicais (Figura 1). Em decorrência do crescimento global da população, urbanização, distribuição e favorecimento da propagação do principal mosquito vetor, Aedes aegypti, a dengue é uma doença emergente com co-circulação de diferentes sorotipos do vírus, o que aumenta a freqüência de epidemias e introduz a febre hemorrágica da dengue (PINHEIRO & DA ROSA, 1991; LEITMEYER et al., 1999).
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Rev. Saúde Pública  vol.43 número1

Rev. Saúde Pública vol.43 número1

To Roberto C. Peres and Reginaldo L.S. Rêgo, from Instituto Oswaldo Cruz, for their technical support and Mauro Brandolini, Fábio Castello and Fernando Alves, from the Dengue Control Campaign of the city of Rio de Janeiro, for fi eld collections; to the Health Department of Paraná and Dr. Álvaro Eiras for providing Adultraps and MosquiTRAPs, respectively.

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

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

The interpretation of results of tests using diagnostic doses was based on the criteria proposed by Davidson and Zahar (1973). The mosquito population was consid- ered susceptible if the average percentage of mortality was > 98%, resistant if mortality was below 80% and in an intermediate situation indicating incipient resistance when mortality was in the range 80-98%. The results presented in Table I show that only Marília and Presidente Prudente Ae. aegypti populations are susceptible to both temephos and fenitrotion. The Bauru population is susceptible to temephos and Campinas mosquitoes remain susceptible to fenitrothion. An altered response for both insecticides was recorded in Araçatuba, Barretos, Ribeirão Preto, São José do Rio Preto and Pirituba while mosquitoes from Santos were classified as resistant for both insecticides. In the estimation of the resistance ratio, a similar pattern of response of the populations was observed. The popu- lations of Ae. aegypti from Presidente Prudente, Marília and Bauru showed the smallest resistance ratios as al- ready observed in 1998 (Macoris et al. 1999). There is a gradient response for populations that had an altered re- sponse in diagnostic dose tests and the mosquitoes from Santos, which were classified as resistant in the diagnos- tic test, showed the highest resistant ratio for both insec- ticides.
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Dengue serotype-specific immune response in Aedes aegypti and Aedes albopictus

Dengue serotype-specific immune response in Aedes aegypti and Aedes albopictus

termine the effect of DENV serotype on infection and innate immune response related gene expression. Indi- vidual female bodies were homogenized by hand using an Eppendorf tube mortar and pestle and RNA extracted using Trizol Reagent (Invitrogen, Carlsbad, CA) using previously established methods (Shin et al. 2014). Quanti- tative real time polymerase chain reaction (qRT-PCR) was performed on cDNA, synthesized with Enhanced Avian Reverse Transcriptase (Sigma, St. Louis, MO) and qRT- PCR conducted using SsoAdvanced SYBR Green Super- mix (Bio-Rad, Hercules, CA) and primers specific to the antiviral genes of interest (Table I) (Nene et al. 2007) on the Bio-Rad CFX96™ Real-Time PCR Detection System and following the included protocols. Two technical rep- licates were performed for all qRT-PCR reactions. The standard curve is generated based on the expression of the Ae. aegypti ribosomal protein S7 gene (GenBank Ac- cession # AY380336). Primers to known antiviral genes were designed based on the Ae. aegypti genome as the Ae. albopictus genome is not fully annotated. Primer com- patibility was verified using blast analysis to find highly similar genes in the Ae. albopictus database, and vice ver- sa. Primer pairs designed to one species that proved un- successful in product amplification in the second species were redesigned to be species specific (Table II). Melt- ing curves from qRT-PCR reactions were evaluated for redundant primer binding. The expression of each gene was compared with non-infectious (i.e., no DENV pres- ent) blood-fed mosquitoes. The time points post-infection
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Comunicação educativa em saúde : a experiência das escolas em dois municípios brasileiros na prevenção das arboviroses

Comunicação educativa em saúde : a experiência das escolas em dois municípios brasileiros na prevenção das arboviroses

Essa dissertação integra o projeto Arbocontrol realizado pela Universidade de Brasília- UnB, e busca conhecer as práticas desenvolvidas pelos professores em sala de aula para o combate e prevenção das arboviroses Dengue, Zika e Chikungunya. O ambiente escolar é um espaço para formação do individuo e troca de saberes de maneira dialógica. Para que haja educação é necessário dois envolvidos ou mais, para que seja colocada em prática a ação de se comunicar. Essa dissertação tem como objetivo analisar as ações realizadas pelos profissionais da educação nas escolas da rede pública, voltadas para o controle e prevenção da Dengue, Zika e Chikungunya nos municípios de João Pessoa (PB) e Cascavel (PR). O caminho metodológico percorrido teve como abordagem a pesquisa qualitativa observacional não participante. A coleta de dados foi realizada por meio de entrevista semi-estruturada com professores da rede pública. Foram realizadas 23 entrevistas, dessas 18 foram analisadas segundo critérios de inclusão. Foi realizada análise de conteúdo para interpretação e compreensão dos discursos dos(as) entrevistados(as). A análise dos achados possibilitou o surgimento de quatro categorias: Educação em Saúde; Comunicação em Saúde; O encontro entre Comunicação e Educação; e O conhecimento sobre as arboviroses dengue, Zika e chikungunya. Por meio dos discursos foi analisado a metodologia aplicada nas atividades realizadas nas escolas e pelos professores, para o combate e prevenção das arboviroses. Ao analisar os discursos dos entrevistados, notamos que os professores tem conhecimento e domínio sobre a temática das arboviroses e reconhecem como um problema de saúde. Os professores buscam desenvolver ações de educomumicação e de comunicação educativa para a prevenção de agravos e mostram a participação dos alunos por meio do conhecimento adquirido com as trocas de conhecimentos que eles compartilham com os familiares e orientam os demais para uma mudança de hábito que todos sejam envolvidos, as escolas buscam mostrar aos alunos a importância de cuidar do ambiente e não jogar lixo nas ruas, buscam trabalhar com a reutilização de materiais recicláveis como pneus, garrafas e outro. No dia a dia escolar os professores realizam ações de comunicação educativa onde busca-se a construção do individuo. No contexto escolar os professores realizam ações com materiais educomunicativos produzidos e disponibilizados pelo Ministério da Saúde, porém poucos sabem da disponibilidade e do acesso a esse material. Com a realização frequente de ações educomunicativas e de comunicação educativa pode-se alcançar a prevenção efetiva de agravos em saúde.
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Dengue e dengue hemorrágico em Belo Horizonte, 1996 - 2001

Dengue e dengue hemorrágico em Belo Horizonte, 1996 - 2001

Alguns estudos têm sugerido que as maiores taxas de incidência da dengue no sexo feminino poderiam ser explicadas pela maior exposição peridoméstica ao vetor (Kaplan et al., 1983; Rosa, 2000). Poderiam também ser determinadas pelo horário diurno de funcionamento da grande maioria das unidades básicas de saúde, dificultando o acesso e o diagnóstico da doença na população masculina inserida no mercado de trabalho (Pontes & Ruffino-Netto, 1997). A semelhança nas taxas de incidência da doença entre os sexos nos três grupos de idade abaixo de 20 anos, conforme observado neste estudo, pode indicar que a transmissão domiciliar e peridomiciliar da doença (local em que crianças e adolescentes permanecem a maior parte do tempo) seja igual entre os dois sexos. No entanto, para a população acima de 60 anos seria esperada a mesma ocorrência da doença em relação ao sexo, fato não observado em Belo Horizonte. Outros fatores relacionados, como a maior imunocompetência das mulheres, maior oportunidade de acesso ao diagnóstico clínico, melhor vigilância e notificação de casos em grupos mais vulneráveis, podem estar envolvidos na ocorrência diferenciada da doença entre os sexos (Díaz et al., 1988).
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Distribuição espaço-temporal do Aedes (Stegomyia) aegypti (Diptera: Culicidae) e casos de dengue e avaliação de variáveis climáticas em Porto Alegre (RS)

Distribuição espaço-temporal do Aedes (Stegomyia) aegypti (Diptera: Culicidae) e casos de dengue e avaliação de variáveis climáticas em Porto Alegre (RS)

O estimador de densidade de Kernel (EDK) mostrou um hotspot de casos de dengue no bairro Partenon, mesma região em que a estatística de varredura circular espaço-temporal identificou um conglomerado. A concordância entre as duas metodologias reforça a importância dessa área de risco e a necessidade de intervenções nos fatores que aumentam a possibilidade de proliferação do vetor. O EDK igualmente apontou vários hotspots do vetor no município, inclusive no bairro Partenon. De 2012 a 2013, observou-se o aumento das regiões de alta infestação de fêmeas de Ae. aegypti, sugerindo uma dispersão do vetor pelo município para locais onde havia condições ideais para proliferação. Em 2012, havia várias regiões de densidade média (coloração amarelo e laranja), de acordo com a escala adotada no presente estudo, que se tornaram de alta densidade (coloração avermelhada) em 2013. Em estudo realizado em Recife (PE) usando armadilhas de oviposição e utilizando o EDK, constatou-se a diminuição da abundância do vetor, através da observação da diminuição das áreas de alta densidade de um ano para o outro (Regis et al. 2013). No entanto, os resultados do presente trabalho com armadilhas para captura de adulto não corrobora com o observado em Recife (PE), pois observou-se em Porto Alegre o aumento dos hotspots, indicando elevação da densidade do vetor na região.
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Insecticide resistance in the dengue vector Aedes aegypti from Martinique: distribution, mechanisms and relations with environmental factors.

Insecticide resistance in the dengue vector Aedes aegypti from Martinique: distribution, mechanisms and relations with environmental factors.

insecticide resistance in mosquitoes [10]. In Martinique island, temephos (AbateH) was used for decades for larval control (abandoned in 2009 to respect the recent European biocide legislation; European Commission Environment Biocidal Products, 1998) and now Bacillus thuringiensis var israelensis (Bti, Vectobac H) is the only insecticide used for such application. Space spraying treatments with vehicle-mounted or portable thermal fogger (aerial or inside application, respectively) are implemented during inter-epidemic periods (i.e. when high entomological indices are reported) and during outbreaks to rapidly kill infected adult mosquitoes [11]. DDT and several OPs (e.g., malathion, fenitrothion) were used since the 1950s but there was a switch to PYRs in the early 1990s [5] because of their rapid knockdown action and low mammalian toxicity (WHO, 2006b). Currently, deltamethrin (K-Othrine 15/5H) and to a lesser extend synergized natural pyrethrins (AquaPyH) are used for the control of adult mosquitoes. In addition, Martinique is an island with intensive agriculture practice (mainly sugar cane and bananas) where huge amount of pesticides have been applied for crop protection. Pesticides used in agriculture include organochlorines (OCs), OPs and carbamates. Recently, Bocquene´ and Franco [12] reported the widespread contamination of rivers and soils in Martinique with pesticides and particularly with high levels of the OCs chlordecone and lindane. The constant exposure of the mosquito populations to these pesticides associated with the increasing urbanization may have led to the selection of particular detoxification genes and to an increased tolerance to pesticides [13,14,15,16].
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Zika Virus: A New Animal Model for an Arbovirus.

Zika Virus: A New Animal Model for an Arbovirus.

In the latest issue of PLOS Neglected Tropical Diseases [1], Dowall and colleagues describe a novel small animal model for Zika virus infection. Along with two other reports in the recent weeks [2,3], this collection of papers marks an important turning point in Zika virus research and enables in vivo testing and evaluation of candidate vaccines and therapeutics. The authors show that type-1 interferon receptor deficient mice (A129), in contrast to the parental strain (129Sv/Ev), are susceptible to Zika infection.
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Rev. Saúde Pública  vol.25 número3

Rev. Saúde Pública vol.25 número3

Susceptibility of Aedes aegypti larvae to temephos and Bacillus thuringiensis var israelensis in integrated control.. The susceptibility of field collected Aedes aegypti larvae was evalu[r]

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Rev. Soc. Bras. Med. Trop.  vol.35 número3

Rev. Soc. Bras. Med. Trop. vol.35 número3

Abstract Software for pattern recognition of the larvae of mosquitoes Aedes aegypti and Aedes albopictus, biological vectors of dengue and yellow fever, has been developed. Rapid field identification of larva using a digital camera linked to a laptop computer equipped with this software may greatly help prevention campaigns. Key-words: Aedes aegypti. Larva. Pattern recognition.

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