Assessing the effect of Aedes (Stegomyia) aegypti (Linnaeus, 1762) control based on machine learning for predicting the spatiotemporal distribution of eggs in ovitraps.

Background: Aedes aegypti is the dominant vector of several arboviruses that threaten urban populations in tropical and subtropical countries. Because of the climate changes and the spread of the disease worldwide, the population at risk of acquiring the disease is increasing. Methods: This study investigated the impact of the larval habitats control (CC), nebulization (NEB), and both methods (CC + NEB) using the distribution of Ae. aegypti eggs collected in urban area of Santa Bárbara d'Oeste, São Paulo State, Brazil. A total of 142,469 eggs were collected from 2014 to 2017. To verify the effects of control interventions, a spatial trend, and a predictive machine learning modeling analytical approaches were adopted. Results: The spatial analysis revealed sites with the highest probability of Ae. aegypti occurrence and the machine learning generated an asymmetric histogram for predicting the presence of the mosquito. Results of analyses showed that CC, NEB, and CC + NEB control methods had a negative impact on the number of eggs collected in ovitraps, with effects on the distribution of eggs in the three weeks following the treatments, according to the predictive machine learning modeling. Conclusions: The vector control interventions are essential to decrease both occurrence of the mosquito vectors and urban arboviruses. The inference processes proposed in this study revealed the relative causal impact of distinct mosquito control interventions. The spatio-temporal and the machine learning analysis are relevant and Powered by Editorial Manager® and ProduXion Manager® from Aries Systems Corporation robust analytical approach to be employed in surveillance and monitoring the results of public health programs focused on combating urban arboviruses.

Spatial-temporal distribution of Aedes (Stegomyia) aegypti and locations of recycling units in southeastern Brazil.

BACKGROUND: Dengue is an arbovirus disease that threatens approximately 200 million people annually worldwide. Aedes (Stegomyia) aegypti (Linnaeus, 1762) is anthropophilic mosquito, extremely well adapted to the urban environment and utilizes varied habitats for egg-laying and development. This study analysed the distribution of mosquito larvae and eggs in urban area of Santa Bárbara d'Oeste, São Paulo, Brazil. The spatial correlation between locations in which people store recyclable materials and the distribution of larvae and eggs were verified. METHODS: Larvae and ovitrap egg collections were conducted from 2014 to 2016. All persons who stored recyclable materials for living were registered and georeferenced. The Mann-Kendall test was used to verify spatial and temporal trends in the number of eggs and larvae/pupae. Euclidian distance map was constructed to correlate recyclable collectors and Ae. aegypti, and Moran's index was employed to verify their spatial autocorrelation and identification of groupings. RESULTS: A total of 137,825 eggs and 16,393 larvae were collected in different habitats from 2014 to 2016. The analyses showed that there was a spatial correlation between larvae and eggs collected, and these two kinds of surveys also presented a spatial correlation with the handling of recyclable materials. The results of the analyses showed significant spatial correlations between eggs and recyclable material collectors and between larvae and collectors. CONCLUSION: The entomological surveillance conducted using ovitraps as a proxy for the presence of Ae. aegypti is an efficient and sensitive method for monitoring the presence of mosquitoes and the impact of interventions employed for decreasing vector populations. Mosquito surveys employing ovitraps should be used more often in routine activities aiming to control dengue through vector control interventions. The locations used to store recyclable materials have a significant relationship with the maintenance of the dengue virus infection in the area. Further studies will be needed to analyse the contribution of recyclable locations, for which there is no ideal infrastructure to minimize the potential use of these materials as mosquito habitats. The entomological surveillance focused on locations of recyclable materials involving interventions that are different from those commonly used in Ae. aegypti control.

The influence of urban heat islands and socioeconomic factors on the spatial distribution of Aedes aegypti larval habitats.

We addressed the potential associations among the temporal and spatial distribution of larval habitats of Aedes (Stegomyia) aegypti, the presence of urban heat islands and socioeconomic factors. Data on larval habitats were collected in Santa Bárbara d'Oeste, São Paulo, Brazil, from 2004 to 2006, and spatial and temporal variations were analysed using a wavelet-based approach. We quantified urban heat islands by calculating surface temperatures using the results of wavelet analyses and grey level transformation from Thematic Mapper images (Landsat 5). Ae. aegypti larval habitats were geo-referenced corresponding to the wavelet analyses to test the potential association between geographical distribution of habitats and surface temperature. In an inhomogeneous spatial point process, we estimated the frequency of occurrence of larval habitats in relation to temperature. The São Paulo State Social Vulnerability Index in the municipality of Santa Barbára d'Oeste was used to test the potential association between presence of larval habitats and social vulnerability. We found abundant Ae. aegypti larval habitats in areas of higher surface temperature and social vulnerability and fewer larval habitats in areas with lower surface temperature and social vulnerability.

Spatial distribution of Culicidae (Diptera) larvae, and its implications for Public Health, in five areas of the Atlantic Forest biome, State of São Paulo, Brazil

ABSTRACT In view of the adaptive ability of mosquitoes and their role in the transport of infective agents, entomological surveys undertaken in transitional environments are very important for the determination of the risk they represent for Public Health. Among the principal vectors of the infectious agents involved in the occurrence of important arboviruses, such as dengue, for example, are the Culicidae-insects capable of installing themselves in the urban nuclei, which exist within areas containing vestigial forests. This present study conducted a survey of mosquito species by means of traps to catch their larvae installed in five rural areas within the Atlantic Forest domain and containing its vestigial vegetation in the municipality of Santa Bárbara D'Oeste, São Paulo, Brazil. A total of 13,241 larvae belonging to six mosquito species were collected on 920 occasions (32.52% of positive collections). Aedes albopictus (64.23%) and Aedes aegypti (32.75%) were the most frequent, followed by Culex quinquefasciatus (1.32%), Aedes fluviatilis (1.04%), Culex Complex Coronator (0.40%) and Toxorhynchites theobaldi (0.22%). Three areas were analyzed by means of Simpson's diversity index and the spatial analysis showed that the sites with the greatest abundance of Ae. aegypti presented lower diversity values and were associated with more highly consolidated urban nuclei. The vector of dengue, chikungunya and zika has great infesting ability in urban areas, which means that the early implementation of entomological surveillance and control activities in specific areas - such as transitional ones - is highly important.

Entomological surveillance, spatial distribution, and diversity of Culicidae (Diptera) immatures in a rural area of the Atlantic Forest biome, State of São Paulo, Brazil.

Because of the high adaptive capacity of mosquitoes, studies that focus on transitional environments become very important, such as those in rural areas, which are considered as bridges between wild diseases and human populations of urban areas. In this study, a survey of the existing species of mosquitoes was performed in an Atlantic Forest area of the city of Santa Bárbara d'Oeste, São Paulo state, Brazil, using traps for immatures and analyzing the frequency and distribution of these insects over the sampling months. Five mosquito species were found: Aedes albopictus (the most frequent species), Aedes aegypti, Aedes fluviatilis, Culex quinquefasciatus, and Toxorhynchites theobaldi. The 4,524 eggs collected in ovitraps showed the presence of the tribe Aedini. Aedes aegypti and Ae. albopictus were identified after larval hatching in the laboratory, with different spatial distributions: the first of which coincides with the area of greatest diversity calculated using the Simpson index, while the second does not. The association of ecological analysis of spatial diversity with simple methods of data collection enables the identification of possible epidemiological risk situations and is a strategy that may be implemented to monitor ecological processes resulting from the interaction among different species of mosquitoes.

Spatial evaluation of larvae of Culicidae (Diptera) from different breeding sites: application of a geospatial method and implications for vector control / Avaliação espacial de formas larvais de Culicidae (Diptera) em diferentes criadouros: aplicação de um método geoespacial e implicações para o controle de vetores

Spatial evaluation of Culicidae (Diptera) larvae from different breeding sites: application of a geospatial method and implications for vector control. This study investigates the spatial distribution of urban Culicidae and informs entomological monitoring of species that use artificial containers as larval habitats. Collections of mosquito larvae were conducted in the São Paulo State municipality of Santa Bárbara d' Oeste between 2004 and 2006 during house-to-house visits. A total of 1,891 samples and nine different species were sampled. Species distribution was assessed using the kriging statistical method by extrapolating municipal administrative divisions. The sampling method followed the norms of the municipal health services of the Ministry of Health and can thus be adopted by public health authorities in disease control and delimitation of risk areas. Moreover, this type of survey and analysis can be employed for entomological surveillance of urban vectors that use artificial containers as larval habitat.

Avaliação espacial de formas larvais de Culicidae (Diptera) em diferentes criadouros: aplicação de um método geoespacial e implicações para o controle de vetores. Este estudo investiga a distribuição espacial da fauna urbana e de Culicidae e informa o monitoramento entomológico de espécies que usam recipientes artificiais como habitat larval. Coletas de larvas de mosquitos foram realizadas no município paulista de Santa Bárbara d' Oeste entre os anos de 2004 e 2006, durante visitas casa-a-casa. Um total de 1.891 amostras foi considerado, com nove espécies diferentes coletadas. A distribuição das espécies foi avaliada através do método de krigagem estatística extrapolando as divisões administrativas do município. O método de coleta adotado no presente estudo está de acordo com os métodos sugeridos aos serviços de saúde municipais pelo Ministério da Saúde e pode, portanto, ser adotado pelas autoridades públicas de saúde no controle da doença e delimitação das áreas de risco. Além disso, este tipo de levantamento e análise pode ser empregado como vigilância entomológica de espécies de mosquitos vetores que usam recipientes artificiais como habitat larval em áreas urbanas.

Estudo epidemiológico dos casos de dengue no município de Santa Bárbara d'Oeste/SP - 2010 / Epidemiological study of dengue cases in the municipality of Santa Bárbara d'Oeste

O objetivo deste estudo é apresentar o perfil epidemiológico dos casos dedengue, ocorridos no município de Santa Bárbara d’Oeste, SP, Brasil, no ano de2010. Foi possível analisar 1.172 fichas de notificação de casos positivos dedengue que ocorreram no município, identificados por exames laboratoriais e por critério clínico-epidemiológico. Os casos se concentraram nos primeiros meses do ano e o isolamento viral identificou a circulação de dois sorotipos da doença, DEN-1 e DEN-2. Casos positivos de dengue, classificados como importados, foram notificados no início da transmissão, e posteriormente foram sucedidos pelos autóctones. Os homens foram mais acometidos pela doença. A faixa etária com maior número de casos foi de 15 a 19 anos; no entanto, os valores referentes às faixas etárias subseqüentes (20 a 24, 25 a 29, 30 a 34 e 35 a 39) também apresentaram valores significativos de ocorrência. Os sintomas que predominaram entre as notificações foram: febre, mialgia, cefaleia e artralgia