When temperatures increase, especially in combination with more precipitation, vector borne diseases like malaria and dengue fever increase in frequency and distribution. In particular, areas where the minimum night temperatures increase provide the best conditions for the growth and spread of Anopheline spp. and Aedes aegypti mosquitoes. (McCarthy et al 2001)
Extreme weather variability may also lead to heat stress among vulnerable populations, especially in poor areas. Prolonged heat can also enhance production of smog and dispersal of allergens.