Mosquitoes in Mesa County tested positive for West Nile Virus.
Local officials say this is the first confirmed activity of the virus in area mosquitoes this year.
However, other counties across Colorado have already reported positive tests to the state health department.
Jennifer House is a state public health veterinarian.
"We've recently had an increase in the number of positive mosquitoes," House says. "So far we have been able to find West Nile Virus positive mosquitoes in Boulder, Denver, Larimer, Mesa, Pueblo, and Weld counties."
Earlier this month, Mesa County also saw the first human case of West Nile this year. House says it’s still the only one.
"We've been fortunate in that we have not seen any additional human cases," she says. "However, we do usually start seeing human cases a couple of weeks after we start getting mosquito positives."
Last year, there were 118 cases of the virus reported in Colorado and four people died.
Health officials say the best way to avoid the getting West Nile is by draining standing pools of water, wearing bug repellent and staying away from active mosquito areas.