The New York State Department of Health has confirmed the first locally acquired case of chikungunya in the state. Laboratory testing at the Department’s Wadsworth Center identified the case in Nassau County, Long Island. This is the first time a locally acquired case has been reported in New York State, and the first in any U.S. state or territory since 2019.
Health officials say the patient likely contracted the virus after being bitten by an infected mosquito, though the exact source of exposure is not confirmed. The Aedes albopictus mosquito, which can transmit chikungunya, is present in some downstate areas of New York. Local transmission can happen if a mosquito bites an infected traveler and then bites another person. The disease does not spread directly between people.
“Our Wadsworth Center has confirmed this test result, which is the first known case of locally acquired Chikungunya in New York State. Given the much colder nighttime temperatures, the current risk in New York is very low,” said State Health Commissioner Dr. James McDonald. “We urge everyone to take simple precautions to protect themselves and their families from mosquito bites.”
Chikungunya is a disease spread by mosquitoes and is most common in tropical and subtropical regions. Symptoms can include fever, joint pain, headache, muscle pain, joint swelling, or rash. Most people recover within a week, but joint pain can last longer for some. The illness rarely results in death. Those at higher risk for severe symptoms include newborns infected near birth, adults over 65, and people with chronic conditions like high blood pressure, diabetes, or heart disease.
So far in 2025, three other chikungunya cases outside New York City were connected to international travel to places where the virus is active. Regular testing by the Wadsworth Center and the New York City Department of Health and Mental Hygiene has not found chikungunya virus in local mosquito samples.
Mosquito activity in New York is decreasing as fall brings cooler temperatures.
More information about chikungunya virus can be found here.
