The Iowa Health Department Tuesday confirmed 13 cases of West Nile virus in the state and they say they’re investigating several more. Deputy State Epidemiologist, Ann Garvey, says the dry weather in August helped reduce mosquito populations but the disease carrying pests are still active.

Garvey says most people don’t know they have the virus, but it can be dangerous to some. “About one in 150 will go on to have more serious symptoms like a very high fever, severe headache, encephalitis, meningitis more life threatening complications. People over the age of 50,immune compromised individuals are the greatest risk for developing those more severe symptoms and illness,” Garvey says.

She says the 13 cases are typical for this time of year. She urges everyone to continue taking precautions to prevent mosquito bites.”Some of the best things you can do are wearing DEET or another insect repellent — make sure you are following the labels carefully — and that’s especially important in the peak mosquito hours during dusk and dawn,” Garvey explains.

Changes in the weather also help prompt people to protect themselves. “And now that the temperatures are a bit cooler it’s a little easier for us to wear those long sleeves and pants — those will also help cut down on our mosquito bite exposures,” Garvey says. Garvey says in most cases West Nile presents no symptoms; about 20 percent of the time people can develop mild, flu like symptoms. In extreme cases, especially in the elderly, the disease can be fatal.

There have been no deaths reported in Iowa this year. Iowa had 31 human cases reported in 2012, but no deaths.There were nine human cases of West Nile reported in 2011 with two deaths.