In addition, this study did not consider changes in climate variability, which may have a major effect on the outbreak of diseases. Based on the sensitivity analysis, host densities are extremely important to these predictions. Keeping them constant, as was done in this analysis, could have underestimated or overestimated the impact of climate change on the density of the American dog tick. A second category of vector-borne diseases that can be affected by climate change consists of diseases carried by mosquitoes. Climate changes resulting in more days between 16 and 35deg.
Mosquito populations are also sensitive to the presence of standing water.
Worldwide, mosquito-borne diseases are associated with significant illness and mortality. In the United States, however, vector control programs and improved hygiene have virtually eliminated endogenously transmitted cases of these diseases, with the exception of sporadic outbreaks of arbovirus-encephalitis. Numerous mosquito species are present in the United States, however. Malaria, dengue fever, and arbovirus-induced encephalitides were considered to be significant risks, and yellow fever and Rift Valley fever were considered to be possible risks. The symptoms are highly variable, depending on the species of the agent.