Global warming may cause one million additional deaths from malaria each year, Epstein warns. Epstein also believes that climate change is a major cause of the spread of dengue fever, which now occurs regularly in Asia and throughout Latin America. It is projected that global warming will significantly increase the range conducive to the transmission of both dengue and yellow fever, says Epstein. The transmission season may also be extended in regions that now lie on the margins of the temperature and moisture conditions that allow disease carriers to reproduce. Epstein uses encephalitis as yet another example of a close and real connection between climate change and the spread of vector-borne diseases.
Mosquitoes can transmit several viruses that cause inflammatory brain diseases in humans.
Particularly wet late winter months followed by summer drought, may exacerbate the threat. Epstein emphasises the role of predators. Freshwater fish, birds, reptiles and bats limit the abundance of mosquitoes. Owls, coyotes and snakes help regulate populations of rodents. He provides examples of the drastic consequences of the impact of climate change on predators.