With mosquito season officially over, county officials have reported that a second bird infected with West Nile virus was found locally this summer.
A sage grouse was found in southernmost Routt County, near the Eagle County border, in late August, Routt County Environmental Health Director Michael Zopf said.
The bird was reported by the Colorado Division of Wildlife, so it took a little time for the county to confirm the second positive avian case. The positive is not yet entered into the state system, Zopf said.
A raptor tested positive for the virus earlier this year. The goshawk was found dead on a deck in Hahn's Peak in early July. It's possible that the bird contracted the virus elsewhere and then flew into the county, Zopf said.
A number of other birds was tested for the virus but did not have it, Zopf said.
West Nile virus, which can be deadly to people, 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.
This summer, a mosquito-sampling program was completed by the county for the first time. Through the surveillance, traps were set across the county to collect the insects. Two mosquitoes of the species that typically carries West Nile virus were found but tested negative for the virus. About 20 batches of mosquitoes were examined during the summer.
The testing results suggest West Nile virus is not a significant hazard in this area, Zopf said. But he warned that conditions could change or tests could be incomplete, so people should still be cautious next summer when mosquito season rolls around again.
The county plans to continue with the surveillance next summer and then decide whether to continue.
"The purpose for trapping mosquitoes is really to assess the numbers and types of mosquitoes in an area," Zopf said. From that information, the county can determine whether West Nile virus could be prevalent.
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