The West Nile virus will likely sneak across the borders of the Dakotas and into Montana sometime in the near future. Shortly thereafter the virus is expected to rear its ugly head in Missoula, state and local health experts say. “We can expect to see it in a year,” says Missoula County communicable disease specialist Brant Goode. “I think that’s a pretty quick amount of time.”
First identified in 1937 in Africa, the mosquito-borne virus appeared in New York City in 1999 and has since spread across half the United States, north to Maine and south to Florida, and as far west as Texas and the Dakotas. As of Aug. 2, there have been 36 human cases of West Nile this year, including two deaths. From 1999 through 2001, there were 149 cases of West Nile virus human illness in the United States, including 18 deaths.
The virus primarily affects birds, especially crows and magpies, but can also affect livestock and humans. West Nile is not contagious. Instead, it spreads up and down the continent with migrating birds. When mosquitoes feed on infected birds and become infected, they in turn spread the virus to other animals they bite.
“We’re doing a lot of surveillance,” says state epidemiologist Todd Damrow of the state’s efforts to track the virus.
Working with the Montana Department of Fish, Wildlife and Parks and ranchers, the Montana Department of Public Health and Human Services has been testing insects, birds and horses for the virus.
They have also notified healthcare workers across the state to be on the lookout. As of yet, the tests have all come back negative, but this doesn’t mean the virus hasn’t crossed the state line yet.
“What we can tell is that it’s spreading from state to state pretty rapidly,” says Damrow. “So it’s not that unexpected or surprising that it would head toward Montana.”
According to the Centers For Disease Control, even in areas where the virus is circulating, very few mosquitoes are infected. Even if an insect is infected, less than 1 percent of people who get bitten and become infected will get severely ill.
“Even when it does arrive we can’t expect most mosquitoes to have it,” says Damrow. “But we don’t want to downplay it or pooh-pooh it because it can be very dangerous and even fatal.”
State and local efforts to control and eliminate mosquito breeding grounds will be stepped up in the coming months, says Damrow, but it’s best to take precautions. The most effective safeguards against contracting the illness are avoiding places where mosquitoes are feeding, eliminating pools of standing water in your yard, covering up exposed skin when mosquitoes are feeding, and using insect repellents.