Geohealth: biology based mapping of vector borne disease in the Americas using NASA satellite data / Geosaúde: mapeamento da biologia das doenças vetoriais nas Américas utilizando dados de satélites da NASA

Implementation of a geospatial surveillance and response system data resource for vector borne disease in the Americas (GeoHealth) will be tested using NASA satellite data, geographic information systems and ecological niche modeling to characterize the environmental suitability and potential for spread of endemic and epizootic vector borne diseases. The initial focus is on developing prototype geospatial models for visceral leishmaniasis, an expanding endemic disease in Latin America, and geospatial models for dengue and other Aedes aegypti borne arboviruses (zika, chikungunya), emerging arboviruses with potential for epizootic spread from Latin America and the Caribbean and establishment in North America. Geospatial surveillance and response system open resource data bases and models will be made available, with training courses, to other investigators interested in mapping and modeling other vector borne diseases in the western hemisphere and contributing brokered data to an expanding GeoHealth data resource as part of the NASA AmeriGEOSS initiative.(AU)

A implementação de uma fonte de dados de vigilância e um sistema de resposta geoespacial para doenças transmitidas por vetores nas Américas (GeoHealth) será testada utilizando dados provenientes de satélites da NASA, sistemas de informações geográficas e modelagem do nicho ecológico, para caracterizar a suceptibilidade ambiental e o potencial de dispersão de doenças endêmicas e epizooticas transmitidas por vetores vetores. O foco inicial será o desenvolvimento de protótipos de modelos geoespaciais para a leishmaniose visceral, uma doença endêmica e em expansão na América Latina, e modelos geoespaciais para dengue e outros transmitidos pelo Aedes aegypti (zika, chikungunya), arbovírus emergentes com potencial para disseminação epizoótica pela América Latina e Caribe e estabelecimento na América do Norte. Sistemas de vigilância e resposta geoespacial e modelos de recursos em bases de dados abertas serão diponibilizados, com cursos de treinamento, para outros pesquisadores interessados em mapear e modelar outras doenças transmitidas por vetores no hemisfério ocidental e contribuir intermediando dados para uma fonte de dados GeoHealth em expansão, como parte da Iniciativa AmeriGEOSS, da NASA. (AU)

Geohealth: biology based mapping of vector borne disease in the Americas using NASA satellite data / Geosaúde: mapeamento da biologia das doenças vetoriais nas Américas utilizando dados de satélites da NASA

Implementation of a geospatial surveillance and response system data resource for vector borne disease in the Americas (GeoHealth) will be tested using NASA satellite data, geographic information systems and ecological niche modeling to characterize the environmental suitability and potential for spread of endemic and epizootic vector borne diseases. The initial focus is on developing prototype geospatial models for visceral leishmaniasis, an expanding endemic disease in Latin America, and geospatial models for dengue and other Aedes aegypti borne arboviruses (zika, chikungunya), emerging arboviruses with potential for epizootic spread from Latin America and the Caribbean and establishment in North America. Geospatial surveillance and response system open resource data bases and models will be made available, with training courses, to other investigators interested in mapping and modeling other vector borne diseases in the western hemisphere and contributing brokered data to an expanding GeoHealth data resource as part of the NASA AmeriGEOSS initiative.

A implementação de uma fonte de dados de vigilância e um sistema de resposta geoespacial para doenças transmitidas por vetores nas Américas (GeoHealth) será testada utilizando dados provenientes de satélites da NASA, sistemas de informações geográficas e modelagem do nicho ecológico, para caracterizar a suceptibilidade ambiental e o potencial de dispersão de doenças endêmicas e epizooticas transmitidas por vetores vetores. O foco inicial será o desenvolvimento de protótipos de modelos geoespaciais para a leishmaniose visceral, uma doença endêmica e em expansão na América Latina, e modelos geoespaciais para dengue e outros transmitidos pelo Aedes aegypti (zika, chikungunya), arbovírus emergentes com potencial para disseminação epizoótica pela América Latina e Caribe e estabelecimento na América do Norte. Sistemas de vigilância e resposta geoespacial e modelos de recursos em bases de dados abertas serão diponibilizados, com cursos de treinamento, para outros pesquisadores interessados em mapear e modelar outras doenças transmitidas por vetores no hemisfério ocidental e contribuir intermediando dados para uma fonte de dados GeoHealth em expansão, como parte da Iniciativa AmeriGEOSS, da NASA.

Spatial analysis and risk mapping of soil-transmitted helminth infections in Brazil, using Bayesian geostatistical models.

Soil-transmitted helminths (Ascaris lumbricoides, Trichuris trichiura and hookworm) negatively impact the health and wellbeing of hundreds of millions of people, particularly in tropical and subtropical countries, including Brazil. Reliable maps of the spatial distribution and estimates of the number of infected people are required for the control and eventual elimination of soil-transmitted helminthiasis. We used advanced Bayesian geostatistical modelling, coupled with geographical information systems and remote sensing to visualize the distribution of the three soil-transmitted helminth species in Brazil. Remotely sensed climatic and environmental data, along with socioeconomic variables from readily available databases were employed as predictors. Our models provided mean prevalence estimates for A. lumbricoides, T. trichiura and hookworm of 15.6%, 10.1% and 2.5%, respectively. By considering infection risk and population numbers at the unit of the municipality, we estimate that 29.7 million Brazilians are infected with A. lumbricoides, 19.2 million with T. trichiura and 4.7 million with hookworm. Our model-based maps identified important risk factors related to the transmission of soiltransmitted helminths and confirm that environmental variables are closely associated with indices of poverty. Our smoothed risk maps, including uncertainty, highlight areas where soil-transmitted helminthiasis control interventions are most urgently required, namely in the North and along most of the coastal areas of Brazil. We believe that our predictive risk maps are useful for disease control managers for prioritising control interventions and for providing a tool for more efficient surveillance-response mechanisms.

Spatial analysis of migrating Apis mellifera colonies in Salvador, Bahia, Brazil.

Beekeeping in Brazil is growing but also associated with an increase in the number of human and animal accidents involved. In particular, bees of the Apis mellifera species (Africanized bees) are known for their aggressive behaviour and frequent swarming activity due to their poor adaptation to the human environment. This study analyzed the spatial distribution of occurrences of migratory swarms of A. mellifera and recorded apicultural accidents in the city of Salvador, Bahia, Brazil. The association of demographic and climatic variations on places where the swarms occurred was also evaluated. The study is based on data collected within the frame of the "SOS Bees", a project initiated for the protection of the environment and enforced by a special unit of the military police in Bahia. In the 3-year period from 2000 to 2003, 590 swarms were registered in 75 of the 98 zones of information of Salvador. Three cluster areas, representing 25.4% of all events, were identified. In that period, 316 apicultural accidents were registered involving humans and one involving dogs. The seasonal rise of the monthly average temperature showed an association with the increase of the number of swarming events.

Application of spatio-temporal scan statistics for the detection of areas with increased risk for American visceral leishmaniasis in the state of Bahia, Brazil.

Mirroring the global increase of registered cases of American visceral leishmaniasis (AVL), this infection has become a growing public health problem in Brazil during the last several years. As the traditional approach to control employed by the governmental health agencies has failed to reduce the incidence and epidemic outbreaks of this illness, we propose a re-evaluation of the national strategy of intervention and monitoring. Our thinking is based on a series of spatio-temporal scan statistics of the west-central region of the state of Bahia covering the 11-year period from 1994 to 2004. By analyzing the situation, spatially and temporally, we show that the disease is a not only a growing focal threat but that it is also appearing in the form of endemic clusters in the cities. The areas where the disease has been found have been classified according to the degree of risk of infection for humans and canines. The overall objective of this study was to identify areas of increased risk of AVL, including its seasonality, and to suggest ways and means to improve the detection of the disease. The findings presented here should not only be of interest for the efforts to control AVL in the study area but also be useful for developing control strategies in other endemic regions of Brazil.

Ecological niche modeling for visceral leishmaniasis in the state of Bahia, Brazil, using genetic algorithm for rule-set prediction and growing degree day-water budget analysis.

Two predictive models were developed within a geographic information system using Genetic Algorithm Rule-Set Prediction (GARP) and the growing degree day (GDD)-water budget (WB) concept to predict the distribution and potential risk of visceral leishmaniasis (VL) in the State of Bahia, Brazil. The objective was to define the environmental suitability of the disease as well as to obtain a deeper understanding of the eco-epidemiology of VL by associating environmental and climatic variables with disease prevalence. Both the GARP model and the GDDWB model, using different analysis approaches and with the same human prevalence database, predicted similar distribution and abundance patterns for the Lutzomyia longipalpis-Leishmania chagasi system in Bahia. High and moderate prevalence sites for VL were significantly related to areas of high and moderate risk prediction by: (i) the area predicted by the GARP model, depending on the number of pixels that overlapped among eleven annual model years, and (ii) the number of potential generations per year that could be completed by the Lu. longipalpis-L. chagasi system by GDD-WB analysis. When applied to the ecological zones of Bahia, both the GARP and the GDD-WB prediction models suggest that the highest VL risk is in the interior region of the state, characterized by a semi-arid and hot climate known as Caatinga, while the risk in the Bahia interior forest and the Cerrado ecological regions is lower. The Bahia coastal forest was predicted to be a low-risk area due to the unsuitable conditions for the vector and VL transmission.