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West Nile virus human case reports and medical guidance

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2026-08-20 09:03 UTC → 2026-08-26 13:23 UTC · added ~~removed~~

Health officials in the United States reported the first human cases of West Nile virus for 2026 in Utah and Maryland. In Utah, mosquito testing showed a significant increase in virus detection compared to previous years, while Maryland officials noted that many infections remain asymptomatic. Medical experts have highlighted that while most people do not realize they have contracted the virus, central nervous system involvement occurs in approximately one in 150 cases. Severe symptoms can include high fever, intense headache, lethargy, photophobia, spasms, or paralysis. As there is no specific treatment, medical care remains supportive based on clinical presentation. In Massachusetts, the Department of Public Health has raised the West Nile virus risk level to ‘high’ for several cities, including Boston, Cambridge, Brookline, Everett, Newton, Somerville, and Watertown. This escalation follows the confirmation of a second human case in the state, with the most recent infection occurring in a person in their 60s in Middlesex County, following an earlier case involving a man in his 90s. Authorities warn that mosquitoes can remain active until the first hard frost. To reduce risk, officials recommend using EPA-registered insect repellents, wearing long sleeves and pants, and limiting outdoor activities during peak mosquito hours between dusk and dawn. Residents are also advised to eliminate standing water in containers, such as flowerpots and birdbaths, to prevent mosquito breeding.

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