Missourians tested for West Nile virus

ST. LOUIS -- Twenty-two Missourians have been tested for possible exposure to the West Nile virus, but so far, there have been no confirmed human cases here, a state official said Thursday.

Meanwhile, the virus is the confirmed or suspected cause of death for 23 birds and nine horses around the state, said Dr. Howard Pue, chief of communicable disease control and veterinary public health for the Missouri Department of Health and Senior Services. All of the cases have occurred since late July.

The number of illnesses is up sharply from last year, when West Nile first arrived in Missouri. In 2001, eight birds, all crows, all in St. Louis city or county, were confirmed to have the virus.

"Yeah, that's an escalation," Pue said. "It shows a bigger risk for people."

The 22 humans have been tested for several mosquito-borne illnesses, West Nile among them, Pue said. Fifteen tests were negative; results on the other seven were due today.

The rise in the number of humans seeking testing has coincided with news reports about the disease -- 11 of the tests occurred this week.

"We certainly want and would expect that physicians would be inspecting more people, with all the publicity," Pue said.

Symptoms are similar to the flu -- headache, fatigue, "general yukiness," Pue said. In about 1 percent of human cases, West Nile can cause a serious illness including encephalitis, an inflammation of the brain.

Tentative testing at a University of Missouri-Columbia lab showed that nine horses had West Nile -- seven from the same farm in Cole County in mid-Missouri and one each from Texas and Pettis counties. The state was awaiting final test results from the U.S. Department of Agriculture lab in Ames, Iowa.

Nat Messer, an associate professor of veterinary medicine at the university, said horses seem to be more susceptible to West Nile than other animals, though no one knows why. He encouraged owners to have their horses vaccinated.

West Nile has struck other countries for decades but first showed up in the U.S. in 1999.

On Monday, the virus claimed its first U.S. victim this year -- a Louisiana woman in her 70s who was one of 32 people in Louisiana known to have West Nile.

The Louisiana Health Department was determining if the virus caused two other deaths.

Before the woman's death, the Centers for Disease Control and Prevention had confirmed 185 cases, including 18 deaths, since 1999. The virus has been found in 34 states and the District of Columbia. Older people are most at risk.

Pue said people shouldn't panic -- the odds of getting the disease at all, much less becoming seriously ill, remain quite small. Still, he said awareness was important.

"People just need to be informed and weigh the relative risks," Pue said.

Health experts say the disease is easy to prevent: Spray on DEET-containing mosquito repellent when you go outdoors; don't let puddles collect in flower pots, wading pools or other spots where mosquitoes can breed; and stay indoors at dawn and dusk, when mosquitoes are most active.