Human West Nile Virus Case Confirmed in Williamson County

The Williamson County and Cities Health District has confirmed its first case of West Nile virus in a person this year.

The person, who was diagnosed July 3, is in their 40s and lives in southern Williamson County, the health district said. No other details were available because of patient privacy.

West Nile is only spread by a bite from an infected mosquito. Health districts have been warning that recent rains and flooding could lead to more mosquitoes and cases of mosquito-borne illnesses like West Nile.

"We’re in the midst of mosquito season this year, and this massive rainfall will raise the risk of mosquito-borne diseases in our community," said Austin Public Health Environmental Health Services Division Chief Marcel Elizondo.

Last year, one person in Travis County died from the virus. The last death in Central Texas previously was in 2016 in Bastrop County.

In 2024, Texas had 455 cases of West Nile and 56 deaths, according to the Texas Department of State Health Services.

"Fortunately, most people who contract West Nile virus never develop symptoms, and the risk of getting seriously ill is very low. The best protection is to prevent getting bitten," said Jason Fritz, integrated vector management program lead in Williamson County.

What are the symptoms of West Nile virus?

About 80% of people who contract West Nile virus have no symptoms. Most people who do develop symptoms have fever, headaches, stiff neck, joint pain, body aches, swollen lymph glands, vomiting, diarrhea or a rash. A blood test or a spinal fluid sample can confirm the cause.

You should contact your doctor or go to an emergency room if you are having symptoms, Fritz said.

How can you protect yourself from West Nile virus?

Remember the four D's:

• Drain standing water. Empty buckets, toys, tires, pools, plant pots and clogged gutters. Mosquitoes breed in standing water and need as little as 1 teaspoon to lay their eggs.
• Dusk to dawn. The mosquito that spreads West Nile virus is most active at dusk and dawn.
• Dress: Wear light-colored, loose-fitting clothing and long pants and long sleeves when you are outside. Clothing is available with built-in mosquito protection.
• DEET: Apply insect repellant that has DEET in it. Use it on both skin and clothing.