New York City health officials confirmed the city’s first case of brain swelling West Nile virus this year.
The New York City Health Department announced this on Wednesday contracted West Nile virus after spending time outdoors in areas around and outside the city.
No other details have been released about the person’s identity or how they became ill.
It is the city’s first case of West Nile virus so far in 2026, with 222 cases reported nationwide, mainly in Arizona, Texas And California.
According to the health department, mosquitoes carrying West Nile virus are present in New York from June through October each year, with a peak season between August and September.
The city said it has stepped up mosquito surveillance and expanded control efforts after detecting the virus in mosquito samples in all five boroughs since June, twice as many as last summer.
Although most patients have few or mild symptoms, about one in 150 have potentially life-threatening brain swelling, along with infections and paralysis.
“The good news is that it is preventable,” New York City Health Commissioner Alister Martin said in a statement. “With mosquito season in full swing, we encourage New Yorkers to take extra precautions to minimize the risk of mosquito bites.”
West Nile virus is caused by a bite from Culex mosquitoes (pictured above) and is most common in the Great Plains states
He added that the best steps “to protect yourself are simple: wear insect repellent, cover up at dawn and dusk, and remove standing water around your home.”
West Nile virus is caused by a bite from Culex mosquitoes and is most common in states like the Great Plains North Dakota, South Dakota, Nebraska And Coloradoalthough cities like Los Angeles, Chicago and Dallas-Fort Worth also record high levels due to large populations.
Many of these states have also extended the mosquito season – which runs from late spring to early fall – due to increases in mosquito prevalence later in the year.
The disease usually causes no symptoms, but can cause fever, headache, nausea, diarrhea, joint pain and pain behind the eyes in one in five patients.
About one in 150 cases is neuroinvasive, meaning the virus penetrates the blood-brain barrier and travels to the meninges, causing meningitis and possible paralysis.
West Nile is fatal in about one in 10 people who develop a nervous system infection, or in about one in 1,500 people with West Nile.
CDC data as of August 18 shows 222 human cases of West Nile virus in 32 states so far this year, 156 of which were neuroinvasive. Last year there were a total of 2,100, compared to 1,800 the year before.
Arizona has reported the most with 76, followed by Texas with 31 and California with 29.
However, CDC data often lags behind local health departments.
It’s unclear how many of last year’s cases were neuroinvasive, but CDC data shows there were 1,342 hospitalizations due to neuroinvasive diseases.
No deaths have been recorded this year and 172 last year.
New York City reported 18 human cases of West Nile virus last year, and the state’s total was 59.
Older adults, people with weakened immune systems, and people with certain chronic conditions are at greatest risk for serious illness from West Nile.
Survivors of severe West Nile disease may experience long-term complications, including memory problems, chronic fatigue, muscle tremors or permanent neurological damage.
West Nile virus can be prevented mainly by avoiding mosquito bites.
CDC officials recommend using insect repellents that contain the ingredient DEET, wearing long sleeves and pants outdoors, and staying indoors between sunset and sunrise in the summer.
