Cincinnati Health Department found mosquitoes that tested positive for West Nile virus

Through its regular and ongoing surveillance for mosquito-borne diseases, the Cincinnati Health Department (CHD) has collected a mosquito sample in the Cincinnati area that has tested positive for the West Nile virus.

“Whenever we find West Nile virus in our local mosquito population, we worry about transmission to humans. That is what we want to prevent,” said Grant Mussman, M.D., MHSA, Cincinnati Health Department Commissioner. “We want to encourage Cincinnati area residents to take some simple precautionary measures to protect themselves, their families, and their neighbors.”

There are several things that can be done to help prevent mosquitoes from breeding near homes and to protect people from mosquito bites.

Controlling Breeding Sites:

• Since mosquitoes breed in stagnant water and can do so even in a very small quantity of water, remove any possible breeding areas where mosquitoes could lay eggs.
• Eliminate sources of standing water in your yard such as saucers under flowerpots, children’s toys, wheelbarrows, boats, tires, puddles, etc.
• Replace water in bird baths and outdoor pet dishes at least every week to help eliminate stagnant water.
• Keep the swimming pool circulating, clean and chlorinated, and remove any water that collects on the swimming pool cover.
• Empty out and turn over plastic wading pools or kiddie pools when not in use.
• Keep gutters clean to prevent standing water.

Protecting Yourself:

During mosquito season (May through September for most of the U.S.), limit outdoor activities as much as possible at dusk and dawn, when mosquitoes are the most active. There are mosquito species that bite humans during the day, but these are not known to carry the West Nile virus.

• Wear light-colored, loose-fitting pants and long-sleeved shirts, as well as shoes and socks when outdoors for long periods of time, or when mosquitoes are most active.
• Use an EPA-approved mosquito repellent to protect exposed skin and follow label directions carefully when applying to yourself or your children (https://www.epa.gov/insect-repellents and www.cdc.gov/westnile/prevention).
• Place BTi (Bacillus thuringiensis israelensis) briquettes such as Mosquito Dunks® in standing water that cannot be drained. BTi is lethal to mosquito larvae but harmless to humans, other animals, and aquatic life. It can provide protection for up to 30 days and can be purchased at many hardware stores or gardening centers.
• Repair or replace old and torn screens in doors, windows, and vents. Look for any other possible access points into your home.
• If you choose to use an insect spray to treat your property or yard, be sure to follow label directions carefully.
• For questions or more information regarding West Nile virus or mosquitoes, contact the Cincinnati Health Department’s Technical Environmental Services Unit at 513-352-2922.

Conducting surveillance helps CHD and the Ohio Department of Health (ODH) keep track of the virus so that necessary steps are taken if it becomes a significant threat.

About the West Nile virus:

The incubation period for the West Nile virus, for which there is no vaccine, is usually two to six days but ranges two to 14 days. Most people (70%-80%) who become infected will show no symptoms. About one in five people who are infected will develop a fever with other symptoms such as headache, body aches, joint pains, vomiting, diarrhea, or rash. Most people with this type of West Nile virus disease recover completely, but fatigue and weakness can last for weeks or months.

Finally, less than 1% of people who are infected will develop a serious neurologic illness such as encephalitis or meningitis (inflammation of the brain or surrounding tissues). The symptoms of neurologic illness can include headache, high fever, neck stiffness, disorientation, coma, tremors, seizures, or paralysis. Recovery from severe disease may take several weeks or months. Some of the neurologic effects may be permanent. About 10% of people who develop neurologic infection due to West Nile virus will die.

For more information about the West Nile virus, visit CDC’s website or ODH’s website.