Mosquito warning issued in Iowa

Iowa is seeing an increase in its surveillance system of two mosquito-borne viruses.

Higher numbers of mosquitoes infected with West Nile virus and St. Louis encephalitis virus infection of sentinel chickens prompted a warning today from the Iowa Department of Public Health.

The department's medical director, Dr. Patricia Quinlisk, noted that mosquito-related diseases are most active in late summer and early fall and remain a threat until frost.

Earlier this month, Iowa reported its first human case of West Nile virus this season.

A middle-aged Clayton County woman contracted the virus, but was not hospitalized.

For most people, West Nile virus causes no symptoms, but about 20 percent have symptoms such as fever, headache, body aches and vomiting.

Last year, one Iowan died from the virus, which was first detected in the state in 2002.

Experts say late-season mosquito species are more likely to transmit disease than spring species, so precautions should be taken.

Quinlisk advised eliminating mosquito breeding areas, such as old tires and other containers where rainwater collects, and to use insect repellent when outdoors.

Water in bird baths should be changed every three to four days.

Other tips include using insect repellent with DEET, picaridin, IR3535, or oil of lemon eucalyptus and avoiding outdoor activities at dusk and dawn when mosquitoes are most active.