West Nile virus season arrives in Oklahoma

The mosquitoes hatching in floodwaters across Oklahoma are primarily the species classified as “nuisance mosquitoes,” health officials say. They produce lots of itchy bites, but typically don't transmit diseases.

However, Culex mosquitoes — the primary vector of West Nile virus — also are arriving in the state.

The state Health Department has reported the first three human cases of West Nile Virus this season. The cases were confirmed in residents of Canadian, Grant and Tulsa counties. Health officials expect the number of cases to increase as temperatures rise through the summer.

While floodwater mosquito populations tend to die out three weeks after the rains stop, the Culex species thrives in dry, hot weather.

The population of Culex mosquitoes i s greatest in July through October, health department spokesman Tony Sellars said.

Culex mosquitoes transmit West Nile virus by feeding on infected birds and then biting humans, horses and some other mammals.

Sellars said 80% of people infected with the virus never become ill, but it is detected in their blood. Some experience only a fever, while others suffer other complications. In extreme cases, the disease can be deadly.

An outbreak in 2012 left 15 Oklahomans dead. Health department records show eight deaths in 2013, 10 in 2015, four in 2017 and two last year.

Most people who become ill have symptoms such as a fever, headache, tiredness and body aches that go away on their own. Some may develop a rash on the trunk of the body. In more severe cases, someone can develop meningitis or other neurological disease.

People older than 50 are at greater risk of developing serious illness involving the nervous system.

Summer' s outdoor activities provide plenty of opportunities for encountering infected mosquitoes. Health officials recommend the public practice the four D's to prevent being bitten:

• Apply a mosquito repellent containing DEET or another approved active ingredient.

• Avoid being outdoors between dusk and dawn when the mosquitoes are most active.

• Drain any standing, stagnant water in containers around your home and workplace.

• Dress in long sleeves and long pants.

For more information, go to westnile.health.ok.gov.