Routt County's first study on the number of mosquitoes carrying West Nile Virus in the county suggests there weren't many.
Only about three Culix tarsalis mosquitoes, the species that typically carries West Nile Virus from birds to people and other animals, were trapped, said Routt County Environmental Health Director Michael Zopf. All tested negative for the virus, which can be deadly to people.
The surveillance efforts concluded Sept. 1 after recent frosts and cold weather brought mosquito season in Routt County more or less to an end.
That doesn't mean the virus-carrying mosquitoes weren't here this summer. There may have been spots where the mosquitoes were prevalent but where there weren't traps, for instance.
The study will continue through next summer, with a few improvements, Zopf said. The goal of the study was to determine where mosquitoes that could be carrying the serious and deadly West Nile Virus were in the county and how prevalent they were.
"Things went really well," Zopf said about the study. "I think we learned some lessons."
The county set up mosquito traps in places across the county, including in the Steamboat Springs area, Yampa, Oak Creek and Hayden. The traps collected bugs one day a week. Most of the traps used a light and some carbon dioxide gas to attract the insects, and then pulled them into a bag with a fan.
Next year, Zopf said the traps will be placed in similar locations to build on the data from this summer. However, dry ice probably will be used to trap more insects than the carbon dioxide-producing chemical used this year.
County officials also hope to hire an internist to help set traps, collect the insects and possibly identify the types of mosquitoes. This year, identification and testing of mosquitoes was done at outside labs.
Statewide, Zopf said, there are fewer human cases reported of West Nile Virus this year. Many of those cases are in Mesa County, compared to the prevalence of the virus in the Front Range last year.
Because the virus is so new, it's hard to consider whether there are trends in where and how the virus is moving.
This year, one raptor tested positive for the virus. The goshawk was found dead on a deck in Hahn's Peak in early July.
West Nile Virus was found for the first time in Routt County last summer when one horse and one bird in the county tested positive. Local health officials said it was likely that the horse contracted the virus while in the Front Range area. Nearby Moffat County had two confirmed human infections last summer.
Although mosquito season is about over, that doesn't mean there are "absolutely no mosquitoes" out there, Zopf said. But the county is "pretty much out of the woods," he said.
Recommendations to prevent mosquito bites, such as wearing long sleeves, draining standing water, using insecticides and staying inside at dusk and dawn, will hold for next summer.
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