Reducing The Odds Of A ‘Big Event’

Like weathermen during hurricane season, scientists at the Florida Medical Entomology Laboratory have become remarkably good predictors of the level of havoc a mosquito-borne virus will bring to vulnerable areas of the state each year. St. Louis encephalitis (SLE) — a small but ever-present risk of living in Florida’s mid-portion — makes insect behaviorist Jonathan Day a man worth listening to. Come June 1, he knows if the area needs to be on heightened alert for a “big event” based on prevailing weather patterns, breeding success of wild birds, whereabouts of biting mosquitoes, and, most tellingly, results of blood tests on sentinel chickens. Epidemics, he says, “sort of telegraph themselves.”

The worst one, for which SLE was named, struck Missouri in 1933. Thousands were infected and 201 died. “At one point there were 25 new cases a day,” says Day. Florida has been luckier. A string of five SLE epidemics between 1959 and 1990 involved between 30 and 226 clinical cases causing flu-like symptoms but relatively few deaths.

Read the entire article in the November 2001 issue