The Polk County Health Department is urging residents to protect themselves from mosquito bites as Iowa experiences high levels of West Nile virus activity in the pesky insects. Statewide mosquito surveillance by Iowa State University shows the highest West Nile virus activity at this point in the summer in more than two decades. August and September are typically the peak months for West Nile Virus transmission in Iowa. While no human cases have been confirmed in Polk County yet this year, mosquitoes in Polk County have tested positive for the virus. To protect against mosquito bites, the Polk County Health Department recommends residents use EPA-registered insect repellent, wear long-sleeved shirts, pants and socks when outdoors, treat clothing and gear with permethrin and eliminate all standing water around your home to reduce mosquito breeding sites. For more information on West Nile virus, click here.