Health officials in New York have confirmed the first locally transmitted case of the chikungunya virus in the United States since 2019. The case, identified in Nassau County on Long Island, marks the first instance of domestic transmission in six years. The New York State Department of Health announced Tuesday that the infected individual began showing symptoms in August after traveling within the country but not abroad.
Case Details and Investigation
Authorities have not disclosed the patient’s identity but confirmed that they reside in Nassau County. The local health department said the individual likely contracted the virus after being bitten by an infected mosquito, although there is no evidence of broader transmission in the area. Laboratory testing of local mosquito populations has not detected the presence of the chikungunya virus.
“The risk of transmission at this time is very low,” said State Health Commissioner James McDonald, noting that mosquito activity decreases sharply with cooler fall temperatures. Health officials continue to monitor mosquito pools across Long Island and the greater New York City metropolitan area, where the mosquito species capable of carrying the virus is present.
Understanding Chikungunya
The chikungunya virus is transmitted to humans through the bite of an infected mosquito, primarily the Aedes aegypti and Aedes albopictus species. It cannot spread directly from person to person. The illness is most common in tropical and subtropical regions, including parts of Asia, Africa, and the Americas.
According to the New York State Department of Health, symptoms typically include fever, severe joint pain, headache, muscle aches, joint swelling, and rash. Most people recover within a week, though some may experience lingering joint pain for months. The disease is rarely fatal, but health officials warn that newborns, older adults, and people with chronic health conditions — such as diabetes and high blood pressure — are at higher risk of complications.
Broader Context and Prevention
This case is the first locally acquired chikungunya infection in the U.S. since 2019, when the last domestic transmission was reported. So far in 2025, New York has recorded three other chikungunya cases, all linked to international travel to regions where the virus is endemic.
While chikungunya remains uncommon in the United States, the mosquitoes that carry it are also known to transmit other diseases, including West Nile virus, Eastern Equine Encephalitis, and Jamestown Canyon virus. Health officials encourage residents to take preventive measures such as eliminating standing water, using insect repellent, and wearing long sleeves when outdoors.
Conclusion
The confirmed case of local chikungunya transmission in New York underscores the importance of mosquito surveillance and public awareness. Although the current risk of spread remains low due to seasonal conditions, health authorities are urging continued vigilance. As global temperatures rise and mosquito habitats expand, experts warn that the likelihood of sporadic local outbreaks of tropical viruses may increase in the coming years.