An integrated approach for the assessment of the Aedes aegypti and Aedes albopictus global spatial distribution, and determination of the zones susceptible to the development of Zika virus

Abstract

The Zika virus, one of the new epidemic diseases, is reported to have affected millions of people in the past year. The suitable climate conditions of the areas where Zika virus has been reported, especially in areas with a high population density, are the main cause of the current outbreak and spread of the disease. Indeed, the suitable climatic conditions of certain territories constitute perfect breading nest for the propagation and outbreak of worldwide diseases. The main objective of this research is to analyze the global distribution and predicted areas of both mosquitoes Ae. aegypti and Ae. albopictus which are the main vectors of Zika virus. Physical (SRTM) and climatic variables (WorldClim) were used to obtain the susceptibility maps based on the optimum conditions for the development of these mosquitoes. The susceptibility model was developed using a Species Distribution Model - correlative model, namely the Maximum Entropy, that used as input the spatial references of both vectors (Dryad Digital Repository). The results show the most important classes of each independent variable used in assessing the presence of each species of mosquitoes and the areas susceptible to the presence of these vector species. It turns out that Ae. aegypti has greater global dispersion than the Ae. albopictus specie, although two common regions stand out as the most prone to the presence of both mosquito species (tropical and subtropical zones). The crossing of these areas of greater susceptibility with areas of greater population density (e.g. India, China, Se of USA and Brazil) shows some agreement, and these areas stand out due to the presence of several records of Zika virus (HealthMap Project). In this sense, through the intersection of susceptibility and human exposure the areas with increased risk of development and spread of Zika virus are pinpointed, suggesting that there may be a new outbreak of this virus in these places, if preventive measures are not adopted.

Keywords: Ae. aegypti; Ae. albopictus; Spatial analysis; Susceptibility of Zika virus.