HCPH advises all residents to "Drain, Dunk and Protect" to reduce the mosquito population and prevent West Nile Virus. Photo: icon0.com, Pexels

A second mosquito pool has tested positive for West Nile virus in Hamilton County, this time in Anderson Township.

According to a Wednesday press email from Hamilton County Public Health (HCPH), the most recent positive results came from mosquitoes trapped on July 22.

“Our environmental health specialists will now surveil the area and treat standing bodies of water with larvicide to prevent more mosquitoes from breeding,” the email reads. “Specialists also may speak with residents about mosquito concerns and distribute educational materials.”

Testing standing pools of water for West Nile is standard operating procedure, the department said, noting that such results are “pretty routine” this time of year.

Hamilton County’s first positive case of the summer was reported in early July in Wyoming. HCPH said no human cases of West Nile virus have been reported in the county.

Related

What is West Nile virus?

West Nile virus is a viral disease affecting the central nervous system that can be transmitted to humans by mosquitoes. HCPH said most people who are bitten by an infected mosquito will never become sick, but that everyone should be aware of the symptoms.

Symptoms may develop two to 14 days after someone is bitten by an infected mosquito. Mild symptoms include fever, headache, body aches, nausea, vomiting and sometimes swollen lymph glands or a skin rash on the chest, stomach and back.

Serious symptoms, which appear in less than one percent of those infected, include high fever, headache, neck stiffness, stupor, disorientation, coma, tremors, convulsions, muscle weakness, vision loss, numbness and paralysis.

According to the U.S. Environmental Protection Agency, the average annual incidence of West Nile virus is highest in parts of the Southwest, the Mississippi Delta region, the Great Plains and the Rocky Mountain region. But studies show that warmer temperatures associated with climate change can accelerate the virus as mild winters and drought have been associated with West Nile virus disease outbreaks.

Preventing West Nile virus in your area

HCPH advises all residents to “Drain, Dunk and Protect” to reduce the mosquito population and prevent West Nile Virus:

Drain:

  • Look for and drain sources of standing water on your property – litter, tires, buckets, flowerpots, wading pools and similar items that could create standing water and become mosquito breeding sites.
  • Frequently change water in bird baths and pet bowls.
  • Drain small puddles after heavy rainstorms.

Dunk:

  • Apply mosquito larvicide, sometimes called mosquito “dunks,” to areas of standing water that cannot be drained. The “dunks” are environmentally safe and won’t harm pets. Purchase them at your local hardware store.

Protect:

  • Cut your grass and trim shrubbery.
  • Make sure screens in windows and doors are tight-fitting and free from defect.
  • Wear long sleeves and pants during peak mosquito hours – dawn and dusk.
  • Use an EPA-registered insect repellent such as those containing DEET, picaridin or oil of lemon or eucalyptus. Always follow the directions on the package.

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This article appears in Aug 6-19, 2025.