111 Positive Mosquito Traps, Two Human Cases — West Nile Is Circulating on Both Sides of Flower Mound

If your evening walks, backyard dinners, or kids' outdoor time happen in Flower Mound, this week's public health numbers from both counties are worth a few minutes of your attention.

Tarrant County Public Health confirmed the county's first human case of West Nile virus for the 2026 season on July 24, and the patient has the neuroinvasive form — the more severe type of the disease. No additional information about the patient was released to protect their privacy. Across the county line, Denton County Public Health reported a Denton resident as the first person in the county diagnosed with West Nile virus this year; that individual had the non-neuroinvasive form of the disease.

Two counties. Two human cases. A lot of positive traps between them. As of July 16, 25 mosquito traps in Denton County had tested positive for West Nile virus. As of July 24, Tarrant County Public Health had identified 86 mosquito pools that tested positive for West Nile virus this season. That's 111 confirmed sites combined.

The neuroinvasive case in Tarrant is worth understanding plainly. About 1 in 5 people who contract West Nile will become symptomatic. Most who show symptoms have West Nile fever — headache, fever, fatigue, muscle aches — but less than 1% of those infected develop the neuroinvasive form, with symptoms that can include confusion, tremors, convulsions, muscle weakness, seizures, paralysis, or coma. The neuroinvasive form is fatal for about 1 in 10 of those who develop it, and long-term neurological problems are common among survivors.

No treatment exists to cure West Nile virus infection, and no vaccine has been developed to prevent it — which means keeping mosquitoes from biting you in the first place is the only real protection available.

What you can actually do right now:

• Time outdoors carefully. Mosquito activity peaks around dusk and dawn, though they will bite at any hour — so health officials suggest staying inside during those high-activity windows when possible.
• Use the right repellent. Look for a product containing DEET, picaridin, or oil of lemon eucalyptus.
• Drain standing water. Eliminating standing water around your property and neighborhood reduces the mosquito population where you live. Gutters, plant saucers, birdbaths, buckets — anything that holds water for a few days becomes a breeding site.
• Check the trap maps. Denton County runs a dedicated West Nile web page where residents can view trap maps, fogging schedules, and neighborhood spray maps posted whenever crews head out. Tarrant County Public Health posts the same at tarrantcountytx.gov. Both are updated as new lab results come in.
• Know the fogging schedule. Whenever a trap in an unincorporated part of Denton County comes back positive, county crews respond with overnight ground-level spraying using ultra-low volume insecticide. If you're in one of those areas, check whether your neighborhood is in a scheduled spray zone.

If you develop a sudden high fever, severe headache, stiff neck, or confusion after time outdoors, call your doctor and mention possible mosquito exposure. West Nile virus spreads through the bite of an infected mosquito and is not contagious. The risk of serious illness for any one person remains low, but the virus is moving through mosquito populations on both sides of town — worth keeping in mind before the next evening outside.