Weld County mosquitoes test positive for West Nile virus

DENVER (KDVR) — Weld County officials reported Thursday that three mosquito pools in two county zones have tested positive for West Nile virus and say it’s only a matter of time until they have a human case.

The Weld County Health Department said mosquitoes trapped in areas along Interstate 25 — such as near Johnstown, Milliken, Platteville, Firestone, Dacono and Fort Lupton — have tested positive. Culex mosquitoes (standard mosquitoes) trapped a bit farther east near Greeley, Evans, Kersey and LaSalle have not yet been positive for the virus.

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“The increasing hot weather often leads to favorable conditions for the Culex mosquito that carries West Nile virus,” Jason Chessher, executive director of the Weld County Health Department, said in a release. “The public needs to be vigilant, because West Nile Virus has a permanent summer presence in Colorado.”

What are the symptoms of West Nile virus?

Colorado’s first human case of West Nile virus this year was confirmed in late June in Arapahoe County.

Weld County health officials reported that the number of mosquitoes is increasing, and while there are currently no human cases of West Nile virus in the county, health officials expect this to change as mosquito season continues through July and August.

West Nile virus symptoms can take three to 14 days to appear after an infection, according to the Weld County Health Department. The symptoms can include fever, headache, nausea, vomiting, muscle aches, weakness and rash, but the health department said most infected people do not show any symptoms.

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If the symptoms do develop, the infected individual should immediately seek a health care professional. There are no medications to treat the virus, nor any vaccines for prevention. While fewer than 1% of infected people develop a serious and sometimes fatal neuroinvasive illness from the virus, about 1 in 5 people infected develop a fever and other symptoms.

How to protect yourself from West Nile virus

Nonetheless, health officials recommend that anyone who may be exposed to mosquitoes prevent getting bit by remembering the four Ds:

• Drain standing water around your house regularly — this can include overturned toys, flowerpots, clogged gutters, rain barrels, tires and anything else that holds water

• Dusk and dawn are mosquitoes’ peak activity times. Limit outdoor activities during those hours and take preventative measures for bites

• DEET is the effective ingredient in insect repellant for consumers to look out for. Other effective repellents contain picaridin, IR3535, lemon eucalyptus oil and para-menthane-diol

• Dress to cover your skin: Long sleeves, pants and a hat can help keep bugs from biting

Last year, Weld County reported an unusually high number of West Nile virus cases in humans — 52 in total. The year before, only 35 were reported, and the year before, 26.

As of July 9, the Centers for Disease Control and Prevention has been informed of 15 cases of West Nile virus in humans and seven cases of neuroinvasive human disease cases.

According to the CDC, individuals over the age of 60 and individuals with pre-existing conditions are more at risk for a severe infection from West Nile virus.

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