Allegheny County Health Department identifies first human case of West Nile virus in 2025
The Allegheny County Health Department announced on Monday that it had identified the first human case of West Nile virus in 2025.
The agency has been busy spraying in communities after multiple samples tested positive for West Nile virus.
The health department has conducted spraying in 31 communities across the Pittsburgh area. Samples were found in separate areas from Carrick to Morningside and from Chartiers to East Hills.
The individual who tested positive resides in Plum Borough. On Aug. 14, the health department began additional surveillance in the area and launched an investigation.
The health department said the victim began experiencing symptoms in mid-July. Symptoms include fever, malaise, diarrhea, and anorexia. They are currently recovering at home, according to a news release from the health department.
"It's been in the area for quite a long time, so it's endemic to this area," according to Nick Baldauf, the vector control coordinator.
Carried by mosquitoes native to the area, you can combat West Nile virus if you can snuff out where mosquitoes breed.
"They like small sources of standing water. Things like unkept swimming pools, tires, and children's toys that are unused," Baldauf said.
According to CDC data, between 70 and 80% of people who become infected with West Nile virus do not develop symptoms and are not impacted. Approximately 20% of those who become infected will develop a fever with other symptoms such as headache, body aches, joint pains, vomiting, diarrhea or rash.
Most people with symptoms can recover on their own. Less than 1% of people infected with the virus will develop severe symptoms of neurologic illness caused by inflammation of the brain or spinal cord.
Anyone who believes they or someone they know has West Nile virus should consult a health care provider.
Baldauf said the good news is that the threat of West Nile virus will decrease over the next few months as temperatures drop and daylight decreases.
"It's most important to be vigilant. Mosquitoes that carry West Nile virus are active during the twilight hours. It's a good idea to wear insect repellent, long sleeves, and long pants," Baldauf said.