Climate Change and Mosquito-Borne Diseases

Abstract

Ecology, development, behaviour, and survival of mosquitoes as well as the transmission dynamic of pathogens, strongly depend on climatic factors. Models have been developed to predict forthcoming mosquito-borne diseases scenarios based on estimations of future climate patterns. However, the complex interplay of climate variables with the mosquito-host-pathogen systems rend the overall effect of the climate on the local prevalence of mosquito-borne diseases difficult to determine. Therefore, the assumption that warmer global temperatures will produce increase mosquito proliferation and geographic range may not be entirely true. Furthermore, general climatic observations may not reflect the local microclimates experienced by mosquitoes, mainly by the synantrophic species which live in mild human-modified habitats. Human socio-economic context, community’s culture or behavioural habits are also sidestepped factors prone to influence MBD transmission. This chapter pretends to illustrate the complex scenario where mosquito-borne diseases develop and the myriad of consequences that climate may induce in the incidence of these illness. Different types of models used to predict forthcoming mosquito-borne diseases scenarios are presented as well as the limitations that might preclude their use as tools for the design of surveillance or control strategies. As an example, it is also presented the history of dengue prevention and re-emergence. The evolution of this well documented disease reveals that besides climate, the increase of human population density, the growth urbanized areas, the upsurge of international mobility, the discontinuity of sustainable source-reduction activities and the emergence of insecticide resistance in mosquitoes are also determinants for dengue prevalence increase.