Denton County's First Human West Nile Case of 2026 Has Been Confirmed — and Mosquito Traps Across the County Are Hot

If you've been spending evenings on the back patio, this is worth two minutes of your time.

Denton County Public Health confirmed the county's first human West Nile virus case of 2026 on Friday, July 10. The patient is a Denton resident, diagnosed with the non-neuroinvasive form of the disease. The county isn't releasing further details, citing patient confidentiality, but the case itself is only part of the picture.

The traps were already telling the story. Five mosquito traps in Denton County had tested positive for West Nile virus before this week, marking the start of the 2026 mosquito season. That count was climbing even before Friday's announcement. "We're seeing more positive mosquito traps in the last few weeks," said Juan Rodriguez, DCPH's assistant director and chief epidemiologist, "indicating an increasing risk for contracting West Nile virus, just as we've seen in our first human case of the season."

For Flower Mound specifically: a second mosquito trap in town tested positive for West Nile virus, with the confirmed sample collected in the 7500 block of Emerson Lane. The town scheduled spraying operations within a one-half square-mile radius of that location. Spraying runs between 10 p.m. and 6 a.m. Residents in affected areas are notified through the town's Everbridge notification system and by signs at major intersections.

The timing is not coincidental. Cases are mostly prevalent from summer to early fall, and August is one of the most active months according to CDC data. That means right now — mid-July — is when the season turns serious.

What actually changes your week:

Mosquitoes are most active at dusk and dawn, and health officials recommend avoiding outdoor activity during those windows. That's the dog walk at 7 a.m. and the kids' evening soccer practice. Adjust if you can.

Wear insect repellent containing DEET, picaridin, or oil of lemon eucalyptus — any EPA-registered brand. Mosquitoes can breed in as little as a bottle cap-size pool of stagnant water. Check clogged rain gutters, rot holes in trees, boat covers, outdoor pet bowls, old tires, trash bins, buckets, flower pots, and bird baths. Dump them. Weekly.

For standing water too large to drain — a pond, a non-chlorinated pool — mosquito dunks (Bti briquettes) kill larvae before they become biting adults.

On symptoms: about 1 in 5 people who contract West Nile virus develop symptoms, which usually appear two to six days after a bite and can include fever, headache, body aches, joint pain, vomiting, diarrhea, and rash. There are no medicines to cure or vaccines to prevent West Nile virus. Early medical attention matters if symptoms appear.

The CDC warns that people over 60 are at greater risk for severe illness, as are people with certain medical conditions including cancer, diabetes, hypertension, and kidney disease.

For the county's interactive mosquito map and weekly case updates, go to dentoncounty.gov/WNV.