Cases of West Nile virus soar in NYC, surpassing total number in 2025
The number of Big Apple residents diagnosed this year with the potentially dangerous West Nile virus has surpassed the total number of cases in 2025, according to city health data. At least 30 people have contracted the mosquito-borne disease since the first case of the year was announced early August — a stark contrast a total of 18 cases in 2025.All five boroughs have been plagued by the positive blood-suckers but Brooklyn leads the pack with 11 confirmed cases of the virus.Queens and Staten Island each have seven cases, the Bronx has reported three and Manhattan has two. Of the 30 confirmed cases across the Big Apple, 24 of those are characterized as the more severe West Nile neuroinvasive disease which include encephalitis, meningitis or acute flaccid paralysis.The remaining six cases are classified as West Nile fever, with no evidence of central nervous system involvement.Gotham has also seen an increase in the number of positive mosquito pools plaguing the boroughs — with over 1,700 positive samples in 2026 compared to a little over 1,300 last year. The number of positive blood-sucker samples in the Big Apple this year is a record, according to city health official Sally Slavinski.Slavinski, who works as the director of the city health department Zoonotic and Vector-Borne Disease unit, believes warmer temperatures are to blame for the uptick.
“We know that warmer temperatures can accelerate the mosquito life cycle and speed up viral replication in the mosquito, so that’s gonna shorten the time that it takes for there to be an infected mosquito and then transmit that virus,” Slavinski told Gothamist. “With this increased rainfall and humidity, it makes it easier for mosquitoes to thrive,” she said, adding that “these longer, warmer seasons where we’re having mosquitoes appear earlier and are active later in the year, there’s more opportunity for transmission to occur.”The health department monitors populations of the flying pest and a...