Newstrack: West Nile virus down but not out in Iowa

We're entering peak season for the mosquito-borne virus

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DES MOINES — Iowa is heading into the peak season for West Nile virus with only three reported human cases in 2017, but public health officials say it’s no time to let your guard down.


The cases that have popped up in Allamakee, Ida and Osceola counties are down from 2016, when Iowa confirmed 37 reports and its first death in six years from the disease first detected in the United States in 1999 and present in Iowa since 2002. Overall, Iowa has attributed 463 human infections and 16 deaths to the mosquito-borne virus, state records show.


“The bottom line is it’s still out there, it still causes illnesses and certainly we still want Iowans to take precautions,” said Dr. Patricia Quinlisk, medical director for the Iowa Department of Public Health.

Since West Nile first appeared in Iowa in 2002, it has been found in every county, either in humans, horses or birds, according to state health officials. As of mid-August, 209 human cases had been reported this year from 118 counties in 27 states.

Quinlisk said late summer and early fall are peak seasons for West Nile virus activity in the state. Although the activity is influenced by weather, she was uncertain whether dry conditions have contributed to fewer cases because the mosquitoes that carry West Nile like small puddles that can result from spray irrigation or other weather-related responses.

“There’s not a whole lot that we can do to combat this other than having people use insect repellent and then some areas do have mosquito programs — mostly to deal with nuisance mosquitoes, but not to deal with West Nile specifically,” she said.

Health officials advised Iowans to take precautionary steps to reduce the risk of exposure to West Nile virus, including using insect repellent with DEET, picaridin, IR3535 or oil of lemon eucalyptus.

However, they cautioned that DEET should not be used on infants less than 2 months old and oil of lemon eucalyptus should not be used on children under 3.

Other advice from health experts was to avoid outdoor activities at dusk and dawn when mosquitoes are most active and to wear long-sleeved shirts, pants, shoes and socks whenever possible outdoors.

According to the state health agency, about 20 percent of people infected with West Nile virus will have mild to moderate symptoms such as fever, headache, body aches and vomiting. Less than 1 percent of people infected become seriously ill and rarely, someone dies.

According to the U.S. Centers for Disease Control and Prevention, people over 60 are at greatest risk for severe disease.

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