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Year’s first human cases of West Nile virus reported in Colorado

The first two human cases of the sometimes fatal West Nile virus in Colorado in 2018 have been reported in Weld and Delta counties.

The Journal

Colorado’s first two human cases of the sometimes fatal West Nile virus in 2018 have been reported in Weld and Delta counties.

An adult resident of Mead fell ill on July 27 and was hospitalized the next day, the Weld County Department of Public Health and Environment said. Tests confirmed that the person had the neuro-invasive form of the virus.

Most infected people don’t have symptoms, the Colorado Department of Public Health and Environment said. About 20 percent have flu-like symptoms, and fewer than 1 percent develop a serious illness, such as the one reported in Weld County.

People over age 60 and those with certain medical conditions are at greater risk of serious illness, and the health department says the best way to avoid a mosquito-borne illness is to prevent mosquito bites.

Weekly mosquito testing for West Nile virus began statewide in June, the health department said. Adult mosquitoes are trapped and tested to provide an estimate of the number of infected mosquitoes and which areas are at risk. Virus-positive mosquitoes have been found in Adams, Boulder, Larimer and Weld counties this season.

“Use an effective insect repellent, wear protective clothing or stay indoors when mosquitoes are active, and mosquito-proof your home,” said Jennifer House, state public health veterinarian. Most human West Nile virus cases are reported in August and September.

In 2017, there were 68 human cases of West Nile virus in Colorado, including four deaths.

To protect yourself:

Use insect repellents when you go outdoors. Repellents containing DEET, picaridin, IR3535, and some oil of lemon eucalyptus and para-menthane-diol products provide the best protection.Limit outdoor activities at dusk and dawn, when mosquitoes that carry West Nile virus are most active.Wear long pants, long-sleeved shirts and socks in areas where mosquitoes are active. Spray clothes with insect repellent.Drain standing water around your house, including flowerpots, clogged gutters, rain barrels, birdbaths and puddles.Install or repair screens on windows and doors.For more information, visit the department’s West Nile virus web page.