The shorter days and cooler weather will soon signal to the mosquitoes to head underground. That should help end the epidemic in New York, as well as the malathion insecticide that's being sprayed. So far health officials have confirmed 11 cases of St. Louis encephalitis and three deaths, and are investigating 65 other people who may have been infected. Gubler says he hopes the epidemic will spur other cities to reassess their efforts to protect against St. Louis encephalitis. New York City has not had a comprehensive mosquito control program because it never had a serious mosquito-related epidemic.
Many cities have some form of mosquito abatement program.
Employees monitor the mosquito population and try to control them by spraying the eggs with insecticides to kill them before they hatch. The best programs are places with past problems, such as Florida, Chicago and New Orleans, says Jonathan Day, a professor at the University of Florida's Medical Entomology Lab who is considered a leading expert on mosquitoes and the diseases they carry. After a St. Louis encephalitis epidemic in 1977, Florida set up a program to watch for the disease. The chickens are placed in certain locations and tested weekly. Usually the virus starts showing up in the chickens in September or October.