DENVER (AP) Jefferson County health officials say they've identified their first case of West Nile virus in a mosquito this season.
Officials last month said mosquitoes collected in Adams, Boulder, Delta, Mesa and Weld counties had the virus.
Four human cases of West Nile virus in counties that include Boulder, Pueblo and Saguache have been reported in the state this year.
Initial human symptoms can include fever, headache, nausea, vomiting, muscle aches, weakness and rash. More severe symptoms can include stupor, disorientation, coma, tremors, vision loss, paralysis and even death.
Last year, Colorado reported 322 cases of West Nile virus disease, and seven people died.