Hotter Temperatures Contribute To Greater Numbers Of Human West Nile Virus Infections

Laura C. Harrington, an expert on mosquito-borne diseases and an Associate Professor of Entomology at Cornell University, discussed the factors behind increased reports of West Nile Virus.
She said, “As of August 23, a total of 11 confirmed human cases of West Nile Virus have been reported in New York State, including one death in Onondaga County. To date, more than 700 mosquito pools have tested positive for the virus across the State.
“Late August is typically a time when the number of human cases starts to escalate quickly. This annual trend is most likely due to gradual amplification of the virus over the course of the summer in bird populations, leading to increases in the number of infectious mosquitoes. As a consequence, we are likely only at the beginning of a significant upward trajectory in human cases.
We are concerned that hotter than normal temperatures this summer may be responsible for accelerating viral replication in mosquitoes capable of transmitting the virus leading to an earlier and greater number of human cases and virus-positive mosquitoes. With no vaccine and no specific treatment for West Nile virus, the best prevention is to minimize exposure to mosquito bites through use of repellents, limit outdoor activity and eliminate mosquito breeding sites.”