Mosquitoes infected with West Nile virus (WNV) were detected in Bannock County on June 1, 2017, prompting health officials to remind people to take precautions to fight the bite. The positive mosquitoes, which are the first detected in the state this year, were collected by the Bannock County Mosquito Abatement District.

Last year, 10 counties across the state reported finding WNV-positive mosquito pools; nine people and 10 infected horses were reported. Although this first detection in 2017 occurred in eastern Idaho, WNV has been detected in most counties since it was introduced into the state in 2004; the majority of detections have been in central and southwestern Idaho.

WNV is usually contracted from the bite of an infected mosquito; it is not spread from person-to-person through casual contact. Symptoms often include fever, headache, body aches, nausea, vomiting, and sometimes swollen lymph glands or a skin rash. In some cases, the virus can cause severe illness, especially in people over the age of 50, and may require hospitalization — and lead to death.

“Disease-carrying mosquitoes will be around now until a killing frost so it is critical that you protect yourselves and your family members from their bite,” says Dr. Leslie Tengelsen, from the Idaho Division of Public Health. “Finding positive mosquitoes in one part of the state is an indication that conditions are right for virus transmission; you should avoid mosquito bites even if tests have not yet confirmed the virus in your local mosquitoes.”

To reduce the likelihood of infection, avoid mosquitoes, particularly between dusk and dawn when they are most active. In addition, you should:

• Cover up exposed skin when outdoors and apply DEET or other U.S. Environmental Protection Agency-approved insect repellent to exposed skin and clothing. Carefully follow instructions on the product label, especially for children. When used as directed, EPA-registered insect repellents are proven safe and effective, even for pregnant or breastfeeding women and children over 6-months old.
• Insect-proof your home by repairing or replacing screens.
• Reduce standing water on your property; check and drain toys, trays or pots outdoors that may hold water and harbor mosquito eggs.
• Change bird baths and static decorative ponds weekly as they may also provide a suitable mosquito habitat.

WNV does not usually affect domestic animals, including dogs and cats, but it can cause severe illness in horses and certain species of birds. Although there is no vaccine available for people, there are several vaccines available for horses. People are advised to keep their horses vaccinated annually.

For the latest information, visit www.westnile.idaho.gov.

Media contact: 

Chris Smith

Public Information Officer

(208)334-0668