The virus, which has been found in more than 25 types of mosquitoes, is usually not serious; its most common symptoms include fever and a headache. For some, however, including those with weakened immune systems, as well as the very young and the elderly although this assumption is under fire; the most recent infection, in Washington, D.C., is in a 55-year-old man the virus can be deadly. That risk, slight as it is, has never been more evident than it has been this summer. To date, the Centers for Disease Control report 120 infections nationwide, as well as five deaths from the virus. (There were 83 documented infections and nine deaths in 1999 and 2001 combined). More than half of this summer's infections have been reported since July, a fact that has some researchers speculating we could see an extreme upswing in cases before cooler air settles in for good. And even then, we may not be in the clear; mild winters, like those we've been experiencing lately, create conditions that mosquitoes just love.
Since West Nile first emerged on the U.S. scene in 1999 (previous cases had been documented in Africa, but never North America), the virus has been contained to the eastern U.S. This year, however, marks a southward shift from New York City's suburbs, where many previous infections had occurred: all five of the summer's fatal cases have been recorded in Louisiana. Many of the bugs appear to have headed south for the summer, in search of the water they crave and the moist, warm temperatures required for efficient breeding.
But while Louisianans are scrambling for cover, it's not just southerners who are scared. Americans everywhere are donning pants and long-sleeve shirts and buying up the most powerful mosquito repellents on the market. (Doctors and the CDC recommend using sprays containing DEET.) Towns and cities across the country are also waging war, showering pesticides and larvacides onto vulnerable areas and distributing informative pamphlets door-to-door. Thursday, Health and Human Services Secretary Tommy Thompson announced the government was providing $10 million to study and fight the spread of West Nile virus, and scientists and researchers have descended on Louisiana, hoping to capture a few of the virulent bugs and root out more specifics on the disease.
In the meantime, residents of the eastern U.S. are hoping against hope for some kind of mosquito oriented disaster of Biblical proportions, like a miniature ice age that effects only bugs or perhaps a spate of far-reaching mosquito suicide pacts. Failing that, we can at least keep our fingers crossed for new developments in the world of repellent sprays.