City of Denton Confirms Second Case of West Nile Virus

DENTON, TX, Nov. 6, 2025 - The City of Denton has confirmed its second human case of West Nile Virus, moving the community to Risk Level 5 of the Mosquito Surveillance and Response Plan.

City staff are reviewing all response actions available under Risk Level 5, which is triggered when multiple human cases of the virus are discovered within the same calendar year. At the same time, staff will continue increased monitoring where the virus was detected, treat mosquito breeding areas, and collect and test adult mosquitoes to identify species and check for the virus.

West Nile Virus is transmitted to humans through the bite of an infected mosquito, which acquires the virus from feeding on infected birds. The virus can lead to serious illness or even death.

Even as temperatures begin to fall, preventing mosquito born illnesses remains a priority. Therefore, residents are still advised to take the following precautions:

• Eliminate standing water: Remove standing water around your home, as it serves as a breeding ground for mosquitoes. Common sites include old tires, flowerpots, and clogged rain gutters.
• Avoid outdoor activity during peak mosquito hours: Stay indoors at dusk and dawn when mosquitoes are most active.
• Dress appropriately: Wear long sleeves and long pants when outside.
• Use insect repellent: Apply repellent containing DEET, picaridin, or oil of lemon eucalyptus whenever outdoors.

The City offers a limited supply of Bti briquettes, which kill mosquito larva. Proof of residency is required (driver's license or City of Denton utility bill) with a limit of two per resident. Residents can pick up the Bti briquettes from the following distribution locations:

• Customer Service, 601 E. Hickory St., Ste F, Monday-Friday, 8 a.m. - 5 p.m.
• City of Denton Composting, 1100 S. Mayhill Rd., Tuesday-Saturday, 7 a.m. - 3 p.m.

While the probability of a human outbreak is moderate to high, individuals over 50 years old and those with compromised immune systems are at a higher risk of severe illness if infected with West Nile virus. Symptoms may include fever, headache, muscle and joint pain, nausea, drowsiness, stiff neck, vision problems, body tremors, mental confusion, memory loss, and seizures. While most people infected with West Nile virus will show no symptoms and recover on their own, those experiencing concerning symptoms should contact their healthcare provider immediately.

For more information on prevention and safety tips, visit Mosquito Safety | Denton, TX (cityofdenton.com).