Oklahoma Health Officials Report First Human Cases of West Nile Virus in the State for 2023

OKLAHOMA CITY (KOKH) — On Tuesday, the Oklahoma State Department of Health (OSDH) announced the first report of the first human infection caused by West Nile Virus (WNV).

According to OSDH, over the last month, evidence of WNV activity has increased across the state and is now considered to be widespread. Positive mosquito pools have been identified in many regions of the state, and human infections have occurred in central, south-central, and southeast Oklahoma.

Health officials said WNV spreads through the bite of an infected mosquito. In Oklahoma, WNV is primarily spread by the Culex mosquito, which feeds on infected birds and then spreads the virus when biting humans, horses, and some other mammals. This type of mosquito increases in abundance during mid to late summer when temperatures are high, and the weather pattern is dry.

“We expect human cases of WNV every year,” said Jolianne Stone, the State Epidemiologist. “Typically, summertime is the beginning of the WNV season in Oklahoma, so with more people participating in outdoor activities there are increased opportunities for encountering infected mosquitoes.”

OSDH officials are reminding the public to take precautions to prevent mosquito bites as mosquito surveillance pools in the state show continued WNV activity.

Tips to avoid mosquito bites and prevent WNV:

• Use an insect repellent containing DEET, picaridin, or IR3535 on exposed skin and clothing when going outdoors, particularly between dusk and dawn when mosquitoes are more likely to bite. Insect repellent with permethrin should be used on clothing only.
• Repair or install window and door screens to keep mosquitoes out of the home.
• Prevent items such as buckets, cans, pool covers, flower pots, children’s toys, and tires from holding water to prevent providing mosquitoes a place to breed.
• Empty pet’s outdoor water bowl and refill daily.
• Scrub and refill bird baths every three days.
• Clean leaves and debris from rain gutters regularly to ensure they are not clogged.

Most people infected will likely never experience symptoms. Those who experience symptoms are often mild and may include sudden fever, headache, and body and joint pain.

Recovery usually occurs within one to three weeks.

For more information on WNV, including historical reported cases, click here.