Oakland County detects first probable human case of West Nile virus in 2026

Oakland County announced its first probable case of West Nile virus in 2026, following six other human cases confirmed in Michigan so far.

Oakland County health officials are not releasing further information on the patient. 

The first case in the state for 2026 was detected in August through routine screening of a blood donation, and the first case in Wayne County was detected a few days after.

Oakland County Health Division is encouraging residents to protect themselves against mosquito-borne diseases, including West Nile and eastern equine encephalitis viruses.

"This is an important reminder that West Nile Virus and other similar diseases are present in the Fall," said Kate Guzman, health officer for Oakland County Health Division. "We strongly encourage residents to protect themselves from mosquitoes until the first hard frost of the year."  

According to the Health Division, West Nile virus is a mosquito-borne virus transmitted when mosquitoes bite an infected bird. The virus is then spread to humans through the bite of an infected mosquito.  

How can you protect yourself against mosquito-borne viruses?

Oakland County's Health Division urges residents to protect themselves from mosquito bites by following these instructions: 

• Use an Environmental Protection Agency (EPA) registered insect repellent.

• Get rid of mosquito breeding sites by removing standing water around your home, including any containers that collect water; cleaning clogged roof gutters and treating retention ponds and drainage ditches with a mosquito larvicide.
• Wear long-sleeved shirts and pants.
• Limit outdoor activity from dusk to dawn when mosquitoes are most active.
• Make sure there are no holes in windows and door screens. 
  

What are the symptoms of West Nile virus?

Most people who are infected with West Nile virus do not experience any symptoms or have a mild illness that may include fever, headache and body aches, according to health officials.

However, in some people, West Nile virus can cause serious disease-causing inflammation and swelling of the brain. When an illness is present, it typically begins two to six days after a mosquito bite. 

People over 50 are more likely to develop serious or life-threatening symptoms of West Nile virus.