Topline
The New York State Department of Health has confirmed a case of the mosquito-borne chikungunya virus in Nassau County on Long Island, marking the first locally acquired infection reported in the U.S. since 2019.
Some 88 cases of the mosquito-borne virus have been reported int he US so far this year
AFP via Getty Images
Key Facts
A locally acquired case of chikungunya confirmed on Long Island marks the first instance of local transmission in more than six years, the New York Department of Health reported Tuesday.
Investigators said the virus was likely contracted through a bite from an infected mosquito within the U.S., though the exact source of exposure remains unknown.
Three other chikungunya cases in New York this year have been linked to international travel to regions with active chikungunya outbreaks, health authorities said.
Nationwide, 88 cases have been reported as of September 2025, but this local transmission raises concerns that American mosquitos may now carry the virus, potentially complicating prevention and containment efforts.
The Department of Health advises New Yorkers to use EPA-registered insect repellants, wear long sleeves and pants when outdoors, remove still water around their homes, and repair window and door screens to prevent mosquitoes from getting inside.
Crucial Quote
“Given the much colder nighttime temperatures, the current risk in New York is very low,” said State Health Commissioner Dr. James McDonald. However, he advised “everyone to take simple precautions to protect themselves and their families from mosquito bites.”
What Is Chikungunya Virus?
Chikungunya is a mosquito-born virus that presents most commonly with a headache, muscle pain, nausea, fatigue, rash and swollen joints. While most symptoms usually resolve within two weeks, the “debilitating” joint pain can persist for months or years, according to the World Health Organization. The joint pain is the calling card of chikungunya and, without it, people with the virus can easily be misdiagnosed as having dengue or Zika, making it hard to know exactly how many people are infected. Chikungunya was first detected in southern Tanzania in the 1950s. The name comes from a word in the Kimakonde language of southern Tanzania that means “that which bends up,” meant to describe the contorted posture of people with severe joint pain.
How Does Chikungunya Virus Spread?
Chikungunya can only be transmitted to a person through the bite of an infected mosquito, but people can transmit it right back to the insect. So if a non-infected mosquito bites a person with the chikungunya, it can contract the virus and infect the next healthy person it bites. It is not contagious or transmittable person to person.
Is There A Chikungunya Vaccine?
Yes. There are two approved for use in the United States: IXCHIQ, a live-attenuated vaccine, is approved for people 18 and older and VIMKUNYA, a virus-like particle vaccine, is approved for those 12 and older. The CDC only recommends the vaccine to people traveling to an area with a chikungunya outbreak.
Is There Chikungunya Virus In The United States?
Yes, but it’s not common. In the U.S., chikungunya is primarily found in travelers who’ve been infected in other countries and a locally acquired case hasn’t been reported since 2019. But travel-associated cases are on the rise. Chikungunya was rarely found in the U.S. before 2006, but as many as 28 people per year tested positive from 2006 to 2013. Nearly 3,000 travel-associated cases were identified in 2014 but that number steadily decreased down to 36 in 2021 before slowly climbing again. There were 199 cases found in 2024. In 2025, there have been 88 cases reported so far.
Where Chikungunya Virus Most Commonly Found?
The Centers for Disease Control and Prevention warn that U.S. travelers visiting Brazil, Columbia, India, Mexico, Nigeria, Pakistan, Thailand and the Philippines are at an elevated risk of exposure. The CDC also issued a Level 2 travel alert for Foshan city, and recommends any traveler to the area be vaccinated. People who do visit are encouraged to prevent mosquito bites by wearing insect repellent, long-sleeved shirts and long pants. Pregnant women are advised not to travel to the region.