RESUMO Objetivo. Identificar e descrever, de forma geral, os fatores relacionados à ocorrência de epidemias de dengue no Brasil. Métodos. Revisão sistemática de estudos publicados entre 2008 e 2018 nas bases de dados MEDLINE, LILACS, PubMed, Cochrane, BVS, Web of Science e Scopus e em bancos de teses e dissertações, com o uso de descritores de dengue e de fatores associados à ocorrência de epidemias catalogados no portal DeCS/MeSH. Resultados. Trinta e cinco estudos realizados no Brasil foram selecionados. As epidemias registradas no país foram associadas e/ou correlacionadas a vários fatores como meio ambiente, condições socioeconômicas e climáticas, e aspectos relacionados ao vetor, entre outros. Conclusões. As epidemias de dengue são complexas e multifatoriais. Observou-se que ações contínuas de controle vetorial são essenciais para a redução da população de Aedes aegypti e o controle da doença. Para conter a propagação da dengue são necessárias medidas multissetoriais eficazes, abrangendo saúde, educação, economia, população, negócios e governo. As ações visando à detecção precoce de casos da doença contribuem para prevenir novos surtos epidêmicos.

ABSTRACT Objective. To identify and describe broadly the factors related to the occurrence of dengue epidemics in Brazil. Methods. Systematic review of studies published in Medline, Lilacs, PubMed, Cochrane, BVS, Web of Science, Scopus, and thesis and dissertations databases using descriptors cataloged in DeCs and MeSH on dengue and factors associated with the occurrence of epidemics, published from 2008 to 2018. Results. Thirty-five studies carried out in the country were selected. The epidemics recorded in Brazil were associated and/or correlated with multiple factors such as environment, socioeconomic conditions, climate, and aspects related to the vector, among others. Conclusions. Dengue epidemics are complex and multifactorial. The continuity of the vector control actions was found to be relevant to the reduction of Aedes aegypti and for disease control. To contain the spread of the disease, effective measures are needed in all sectors, including health, education, economy, population, business, and government. Actions for the early detection of cases of the disease can prevent new outbreaks of epidemics.

RESUMEN Objetivo. Determinar y describir de manera amplia los factores relacionados con la aparición de epidemias de dengue en Brasil. Métodos. Se llevó a cabo una revisión sistemática de los estudios publicados en MEDLINE, LILACS, PubMed, Cochrane, BVS, Web of Science, Scopus y en bases de datos de tesis y trabajos de final de grado con los descriptores catalogados en DeCS y MeSH sobre dengue y factores asociados con la aparición de epidemias publicados entre 2008 y 2018. Resultados. Se seleccionaron 35 estudios llevados a cabo en Brasil. Las epidemias registradas en el país se asociaron o se relacionaron con diversos factores, como el medioambiente, las condiciones socioeconómicas, el clima y aspectos relacionados con el vector, entre otros. Conclusiones. Las epidemias de dengue son complejas y multifactoriales. Se constató que la continuidad de las medidas de control de vectores es pertinente para la reducción de Aedes aegypti, así como para el control de la enfermedad. Para contener la propagación de la enfermedad son necesarias medidas eficaces en todos los sectores, como la salud, la educación, la economía, la población, las empresas y el gobierno. Las medidas de detección temprana de casos de la enfermedad pueden prevenir nuevos brotes de epidemias.

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.

The objective of this study was to evaluate the effectiveness of Aedes aegyptimass trapping using the sticky trap MosquiTRAP (MQT) by performing a cluster randomised controlled trial in Manaus, state of Amazonas, Brazil. After an initial questionnaire and baseline monitoring of adultAe. aegyptiabundance with BG-Sentinel (BGS) traps in six clusters, three clusters were randomly assigned to the intervention arm where each participating household received three MQTs for mass trapping during 17 months. The remaining three clusters (control arm) did not receive traps. The effect of mass trapping on adult Ae. aegyptiabundance was monitored fortnightly with BGS traps. During the last two months of the study, a serological survey was conducted. After the study, a second questionnaire was applied in the intervention arm. Entomological monitoring indicated that MQT mass trapping did not reduce adult Ae. aegyptiabundance. The serological survey indicated that recent dengue infections were equally frequent in the intervention and the control arm. Most participants responded positively to questions concerning user satisfaction. According to the results, there is no evidence that mass trapping with MQTs can be used as a part of dengue control programs. The use of this sticky trap is only recommendable for dengue vector monitoring.

A longitudinal study was conducted in Manaus, Brazil, to monitor changes of adult Aedes aegypti (L.) abundance. The objectives were to compare mosquito collections of two trap types, to characterise temporal changes of the mosquito population, to investigate the influence of meteorological variables on mosquito collections and to analyse the association between mosquito collections and dengue incidence. Mosquito monitoring was performed fortnightly using MosquiTRAPs (MQT) and BG-Sentinel (BGS) traps between December 2008-June 2010. The two traps revealed opposing temporal infestation patterns, with highest mosquito collections of MQTs during the dry season and highest collections of BGS during the rainy seasons. Several meteorological variables were significant predictors of mosquito collections in the BGS. The best predictor was the relative humidity, lagged two weeks (in a positive relationship). For MQT, only the number of rainy days in the previous week was significant (in a negative relationship). The correlation between monthly dengue incidence and mosquito abundance in BGS and MQT was moderately positive and negative, respectively. Catches of BGS traps reflected better the dynamic of dengue incidence. The findings help to understand the effects of meteorological variables on mosquito infestation indices of two different traps for adult dengue vectors in Manaus.

Carbon dioxide (CO2) is an important component for activating and attracting host-seeking mosquitoes. The BG-Sentinel(r) trap is a well-established monitoring tool for capturing Culicidae, but CO2 role for the trap effectiveness has not been evaluated in highly urbanised areas. The objective was to evaluate the effectiveness of BG-Sentinel traps baited with and without CO2 for capturing urban mosquitoes. Fifteen areas were selected within the city of Manaus, Brazil, where four BG-Sentinels were operated for 24 h, two of them with CO2 and two without CO2. Captured Aedes aegypti females were dissected for the determination of their parity status. A significantly higher proportion of traps (from 32-79%) were positive for female Ae. aegypti when using the BG-Sentinel with CO2 (χ2 = 11.0271, p ≤ 0.001). Catches of female Culex spp were six times higher in CO2 traps (Mann-Whitney U test = 190.5; p = 0.001). Parity rates were similar for both traps. This study showed that CO2 has primarily an enhancing effect on the efficacy of BG-Sentinel for capturing Culex spp in Manaus. For Ae. aegypti, the positivity rate of the trap was increased, when CO2 was added.

IntroductionIn Manaus, the first autochthonous cases of dengue fever were registered in 1998. Since then, dengue cases were diagnosed by the isolation of viruses 1, 2, 3, and 4.MethodsOne hundred eighty-seven mosquitoes were collected with BioGents (BG)-Sentinel traps in 15 urban residential areas in the Northern Zone of Manaus and processed by molecular tests.ResultsInfections with dengue viruses 1, 2, 3, and 4 and a case of co-infection with dengue viruses 2 and 3 were identified.ConclusionsThese findings corroborate the detection of dengue in clinical samples and reinforce the need for epidemiological surveillance by the Health authorities.

A sticky trap designed to capture gravid Aedes (Stegomyia) aegypti mosquitoes, MosquiTRAP, has been evaluated for monitoring this species in Brazil. However, the effects of trap densities on the capture rate of Ae. aegypti females and the sensitivity of vector detection are still unknown. After a preliminary study has identified areas of high and low female mosquito abundance, a set of experiments was conducted in four neighbourhoods of Belo Horizonte (state of Minas Gerais, Brazil) using densities of 1, 2, 4, 8, 16, 32 and 64 traps per block. Trap sensitivity (positive MosquiTRAP index) increased significantly when 1-8 MosquiTRAPs were installed per block in both high and low abundance areas. A strong fit was obtained for the total number of mosquitoes captured with increasing trap densities through a non-linear function (Box-Lucas) (r² = 0,994), which likely exhibits saturation towards an equilibrium level. The capacity of the Mean Female Aedes Index to distinguish between areas of high and low Ae. aegypti abundance was also investigated; the achieved differentiation was shown to be dependent on the MosquiTRAP density.

INTRODUÇÃO: O conhecimento da fauna de culicídeos em estados da Amazônia Brasileira auxilia no conhecimento da bionomia dos insetos obtidos, além de possibilitar a observação de modificações da fauna ao decorrer do tempo. MÉTODOS: As capturas dos culicídeos foram realizadas em área extradomiciliar de duas zonas rurais de Porto Velho, durante junho e julho, nos anos de 2007 e 2008, com a armadilha BG-Sentinel®. RESULTADOs: Foram coletados 10.695 culicídeos, distribuídos em nove gêneros: Coquillettidia, Culex, Mansonia, Psorophora, Aedes, Aedeomyia, Anopheles, Uranotaenia e Wyeomyia. CONCLUSÕES: Foi registrada pela primeira vez no estado a presença de Mansonia (Mansonia) flaveola.

INTRODUCTION: Knowledge concerning the fauna of Culicidae in the Brazilian Amazon States contributes to current understanding of the bionomics of the insects collected and makes it possible to observe changes in the fauna over time. METHODS: The Culicidae were captured with a BG-Sentinel® trap in extra-domiciliary area of two rural regions of Porto Velho in June and July of 2007 and 2008. RESULTS: A total of 10,695 Culicidae was collected, belonging to nine genera: Coquillettidia, Culex, Mansonia, Psorophora, Aedes, Aedeomyia, Anopheles, Uranotaenia and Wyeomyia. CONCLUSIONS: The presence of Mansonia (Mansonia) flaveola was recorded in the State of Rondônia for the first time.

As limitações na identificação do Aedes aegypti em laboratório e no processamento das informações obtidas em campo pelo método da pesquisa larvária levaram ao desenvolvimento do "Monitoramento Inteligente da Dengue" (MI-Dengue). O MI-Dengue consiste em uma armadilha que captura fêmeas grávidas de Ae. aegypti associada ao sistema informatizado de coleta, transmissão e acesso das informações de campo, e mapas georreferenciados em tempo real. O objetivo deste trabalho foi descrever pela primeira vez um sistema de monitoramento de adultos de Ae. aegypti e apresentar os resultados preliminares em três municípios que adotaram o MI-Dengue como estratégia para identificar áreas e direcionar as ações de controle. Semanalmente, mapas georreferenciados e o indicador entomológico (IMFA) forneceram informações das áreas onde os níveis de infestações, caracterizados por cores em função da quantidade de fêmeas de Ae. aegypti capturadas, indicaram situação de sem risco, alerta e crítica que desencadearam ações de controle. Os resultados preliminares sugerem que a adoção dessa estratégia de controle com visitas casa a casa em um raio de 200m da armadilha positiva contribuiu para a redução de casos de dengue nos municípios que adotaram o MI-Dengue.

Limitations in the laboratory identification of Aedes aegypti and processing of field data based on larval surveys led to the development of the "Intelligent Dengue Monitoring" technology (MI-Dengue). MI-Dengue consists of a trap that captures gravid female Ae. aegypti, coupled with a computerized system for field data collection, transmission, and access to georeferenced maps in real time. The current study describe the first experience with a system for monitoring adult Ae. aegypti and presents the preliminary results in three municipalities that adopted MI-Dengue as a strategy to identify key areas and orient control measures. Weekly georeferenced maps and an entomological indicator (Mean Female Aedes Index) provided information on infested areas and infestation levels, color-coded according to the number of captured female Ae. aegypti, and indicated risk-free, dengue alert, and critical situations that triggered appropriate control measures. The preliminary results suggest that the adoption of this control strategy with house-to-house visits in a 200m radius of the positive trap helped reduce dengue in the municipalities that adopted the system.

As limitações na identificação do Aedes aegypti em laboratório e no processamento das informações obtidas em campo pelo método da pesquisa larvária levaram ao desenvolvimento do "Monitoramento Inteligente da Dengue" (MI-Dengue). O MI-Dengue consiste em uma armadilha que captura fêmeas grávidas de Ae. aegypti associada ao sistema informatizado de coleta, transmissão e acesso das informações de campo, e mapas georreferenciados em tempo real. O objetivo deste trabalho foi descrever pela primeira vez um sistema de monitoramento de adultos de Ae. aegypti e apresentar os resultados preliminares em três municípios que adotaram o MI-Dengue como estratégia para identificar áreas e direcionar as ações de controle. Semanalmente, mapas georreferenciados e o indicador entomológico (IMFA) forneceram informações das áreas onde os níveis de infestações, caracterizados por cores em função da quantidade de fêmeas de Ae. aegypti capturadas, indicaram situação de sem risco, alerta e crítica que desencadearam ações de controle. Os resultados preliminares sugerem que a adoção dessa estratégia de controle com visitas casa a casa em um raio de 200m da armadilha positiva contribuiu para a redução de casos de dengue nos municípios que adotaram o MI-Dengue.

Limitations in the laboratory identification of Aedes aegypti and processing of field data based on larval surveys led to the development of the "Intelligent Dengue Monitoring" technology (MI-Dengue). MI-Dengue consists of a trap that captures gravid female Ae. aegypti, coupled with a computerized system for field data collection, transmission, and access to georeferenced maps in real time. The current study describe the first experience with a system for monitoring adult Ae. aegypti and presents the preliminary results in three municipalities that adopted MI-Dengue as a strategy to identify key areas and orient control measures. Weekly georeferenced maps and an entomological indicator (Mean Female Aedes Index) provided information on infested areas and infestation levels, color-coded according to the number of captured female Ae. aegypti, and indicated risk-free, dengue alert, and critical situations that triggered appropriate control measures. The preliminary results suggest that the adoption of this control strategy with house-to-house visits in a 200m radius of the positive trap helped reduce dengue in the municipalities that adopted the system.

A armadilha de oviposição acrescida de inseticida pode funcionar como novo método de controle de fêmeas do mosquito Aedes aegypti. Fêmeas de Aedes aegypti foram colocadas em contato com ovitrampas letais envelhecidas e a mortalidade variou de 60,3% a 100% sendo significativo o efeito do envelhecimento das palhetas impregnadas com deltametrina no percentual de mortalidade.

Oviposition traps with added insecticide may work as a new method for controlling the females of the Aedes aegypti mosquito. Females of Aedes aegypti were placed in contact with lethal ovitraps with aging. The mortality rate ranged from 60.3% to 100%. The effect of aging the slats impregnated with deltamethrin was significant in relation to the percentage mortality among Aedes aegypti females.

Para avaliar o papel do octenol na coleta de anofelinos foram utilizadas armadilhas HP iscadas com diferentes taxas de evaporação. Foram capturados 285 anofelinos e não houve diferença entre o número de anofelinos coletados com as armadilhas controle e as iscadas com octenol e nem entre as taxas de evaporação.

To evaluate the role of octenol in collecting anophelines, HP traps baited with different rates of evaporation. A total of 285 anophelines was captured and there was no significant difference in the numbers of anophelines captured between the control traps and the traps baited with octenol and no difference between the release rates.

O objetivo deste trabalho foi determinar o padrão gonotrófico de fêmeas de Aedes aegypti em condições de laboratório e de campo. Fêmeas copuladas e alimentadas com sangue de galinha foram transferidas para gaiolas de polipropileno e oferecidos diferentes substratos de oviposição (papel sulfite, filtro, manteiga e toalha). O papel filtro recebeu significativamente maior (40,4%) deposição de ovos do que os demais substratos. Observou-se que maior (35,7% dia modal) oviposição ocorreu ao terceiro dia, após alimentação sangüínea. Foi observada a oviposição das fêmeas a cada duas horas de intervalo, durante o fotoperíodo em laboratório e em campo por meio de ovitrampas. Os resultados de laboratório demonstraram que maior deposição de ovos ocorreu entre a 9ª - 12ª hora da fotofase e 1ª - 2ª hora de escotofase. Em campo maior número de ovos ocorreu entre 9ª - 12ª hora de fotofase e na 1ª - 4ª hora de escotofase. Estes resultados indicam que Aedes aegypti exibiu um padrão na periodicidade de oviposição e podem subsidiar em programas de monitoramento e ou controle do inseto vetor. Sugere-se que, em campo, por exemplo, armadilhas de oviposição (ovitrampa) devem ser instaladas no período da manhã pois as capturas ocorrem a partir do período da tarde.

The object of this work was to determine of gonotrophic diel pattern of female Aedes aegypti in laboratory and field conditions. Three day-old female mosquitoes were the fed on chicken blood and transferred to bioassay cages. Four oviposition substrates were offered: paper sulfite, filter, butter and towel. The results showed that filter paper received a significantly higher (40.4%) percentage of deposited eggs than the other oviposition substrates. After their first blood meal, females started to oviposit on the 3rd model day; 35.7% of the total number of eggs deposited. The oviposition diel patterns of females were observed every two hours during the photoperiod in the laboratory and in the field. In the laboratory, the periodicity of oviposition showed that the highest egg deposition occurred during the 9th- 12th h of photophase and 1st - 2nd h of scotophase. In the field, the highest egg deposition occurred during the 9th - 12th h of photophase and 1st - 4th h of scotophase. These results point out that Aedes aegypti showed an oviposition periodicity pattern that can subsidize monitoring and or control of vector insect. itis suggested that ovitraps should be placed in the field during the morning hours since the captures occur during afternoon.

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

Para avaliar a influência da densidade larval no desenvolvimento do mosquito Aedes aegypti, foram testadas três diferentes densidades. Observou-se que em condições de alta densidade larvária e carência de alimentos houve uma redução no tamanho dos adultos e aumento na taxa de mortalidade de Aedes aegypti em condições de laboratório.

To evaluate the influence of larval density in development of Aedes aegypti mosquitoes we evaluated three different densities. It was observed that conditions of high larval density and shortage of food produced a reduction in the size of adults and increased mortality rate of Aedes aegypti in laboratory conditions.