Health & Fitness

Idaho’s first human cases of West Nile in 2019 have been identified, experts say

Two adults in Washington County were found to have West Nile virus recently, according to the Idaho Department of Health and Welfare, marking the first diagnoses in Idaho in 2019.

A resident older than 30 was diagnosed with West Nile virus neuroinvasive disease, according to a news release, and a resident older than 60 had West Nile virus fever. West Nile virus activity has been found in 10 Idaho counties this year, but these are the first humans infected.

“The detection of West Nile virus-positive mosquitoes has increased significantly during the last few weeks and we strongly encourage Idahoans to fight the bite of mosquitoes to protect themselves and their families,” said Dr. Leslie Tengelsen, state public health veterinarian, in the news release.

“Confirmation of human infection makes it increasingly important for all of us to take protective measures. This includes wearing insect repellent and protective clothing in addition to reducing standing water around our gardens and homes where mosquitoes can lay their eggs.”

There were 16 human West Nile virus infections statewide in 2018, including one that resulted in death. West Nile activity was reported in 18 counties, in mosquitoes, horses or people.

In 2006, Idaho had more West Nile virus illnesses than any other state, with almost 1,000 infections and 23 deaths.

The virus is usually spread from a bite from an infected mosquito. It is not spread through human-to-human contact.

Symptoms of a West Nile infection often include fever, headache, body aches, nausea, and sometimes swollen lymph glands or a skin rash, according to Health and Welfare. Infection can result in severe illness, especially in people 50 and older.

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Reporter Ruth Brown covers the criminal justice and correctional systems in Idaho. She focuses on breaking news, public safety and social justice. Prior to coming to the Idaho Statesman, she was a reporter at the Idaho Press-Tribune, the Bakersfield Californian and the Idaho Falls Post Register.