The Malheur County Health Department has announced that an adult living in the Ontario area has tested positive for West  Nile virus – the first presumptive human case of the virus in Malheur County this year.

West Nile virus is transmitted to humans by mosquitoes which have been infected by feeding on birds which have the virus. In rare instances, the virus may be spread from person to person through organ donation, blood transfusion, breastfeeding, or from pregnant mother to fetus.

The disease affects the nervous system,  and up to 80 percent of people who are infected will not display any signs of illness at all. Those who have underlying health conditions, however, could become seriously ill.

West Nile virus was first detected in the United States in 1999, and the number of Oregonians infected with the virus fluctuates every season.

While most people do not develop symptoms from this virus, some people who develop illness may experience mild symptoms such as fever, headache and body aches; occasionally a skin rash and swollen lymph glands may be noticed. These symptoms may last a few days or as long as several weeks. Those who are older than 50 or have immunocompromised conditions can become seriously ill. Seek medical attention and testing if you develop symptoms compatible with West Nile virus infection.  

People who are concerned about mosquitoes should cover up exposed skin and use an EPA-registered insect repellent according to package directions. Residents are also urged to monitor their own yards and gardens for areas of high mosquito activity, especially standing water that can serve as a breeding ground for mosquitoes. Small amounts of water in a discarded can or container will support dozens of mosquitoes, as will clogged rain gutters or drain pipes.

For additional information on West Nile virus, visit:

Centers for Disease Control and Prevention at https://www.cdc.gov/westnile/index.html

• Centers for Disease Control and Prevention at https://www.cdc.gov/westnile/index.html.
• Oregon Health Authority, West Nile virus information:

https://www.oregon.gov/oha/ph/diseasesconditions/diseasesaz/westnilevirus/Pages/wnile.aspx

• Idaho Department of Health and Welfare, West Nile Virus information https://healthandwelfare.idaho.gov/health-wellness/diseases-conditions/west-nile-virus