Tuesday, March 2, 2004
Even with snow piled high and winter storms in the forecast, Routt County officials are talking about summer and what comes with it: swarms of mosquitoes and the West Nile virus.
Since October, Routt County Environmental Health Director Michael Zopf and Extension Agent C.J. Mucklow have been discussing how to deal with West Nile this summer. They brought preliminary plans to Routt County commissioners Tuesday.
The virus was found in Routt County for the first time last summer, when one horse and one bird in the county tested positive for the virus. Health officials said it was likely that the horse contracted the virus while in the Front Range area. Nearby Moffat County had two human infections last summer.
One focus of preliminary plans is a mosquito surveillance program to track the number and types of mosquitoes in the county. Another focus is teaching people that West Nile is a dangerous disease but is preventable by wearing insect repellent and staying indoors when bugs are feeding.
"The big question is what's going to happen next year," Zopf said. "What's going to happen on the Western Slope at our altitudes, no one really knows."
What is not recommended is a large-scale mosquito spraying program, Zopf emphasized.
Because spraying would be expensive and because the extent of the problem is unknown, county commissioners and County Manager Tom Sullivan agreed it would be best not to spray.
"People taking care of themselves seems to be a better plan ... than trying to go out and spray everything in the country," Sullivan said.
For the mosquito surveillance program, mosquitoes are trapped using a carbon monoxide bait that mimics an exhaled breath from a person, horse or other animal. Traps will be set in May in Steamboat Springs, Oak Creek, Hayden, Yampa and at Steamboat Lake.
Once trapped, mosquitoes are counted and classified by species. The primary species that transmits the virus to people is Culex Tarsalis, a medium-size bug that is active at dawn and dusk. The insects breed in standing water such as irrigated hay meadows, old tires, hoof prints, flower pots, tree holes and more.
"We know we have mosquitoes," Zopf said. "We just don't know what kind they are and when the mosquitoes are out."
Knowing which mosquitoes are prevalent helps county officials decide whether West Nile virus is a big threat in the county and how to deal with it.
The county received a $3,000 grant from the Colorado Department of Public Health and Environment last year to do the surveillance.
Another element of the research could be to test blood samples from horses to get an indication of how many have been infected with the virus and how widespread the virus is. Veterinarians could take the samples while collecting blood from horses for other reasons, and between 50 and 100 samples could then be tested, Mucklow said.
West Nile virus first appeared in the United States in New York in 1999 and has since traveled west, hitting the Eastern Plains and Front Range of Colorado hard in 2003. Last summer, there were more than 2,900 human infections and 54 deaths reported in the state, compared with 13 human cases the year before.
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