New York health officials have confirmed the state’s first locally acquired case of chikungunya virus, and the first such case in the country in six years.

The state Department of Health said Tuesday that the mosquito-borne virus, which has been spreading in China and elsewhere, was identified in a person living in Nassau County on Long Island.

The county's health department, in a separate statement, said the individual began experiencing symptoms in August after having traveled outside of the region, but not out of the country.

It's not clear how exactly the person, who authorities have not named, contracted the virus.

Health officials say the person was likely bit by an infected mosquito, but they also say the virus has not been detected in local mosquito pools and there is no evidence of ongoing transmission.

The type of mosquito known to carry chikungunya is present in parts of the New York City metropolitan area, including suburban Long Island. The disease cannot be spread directly from one person to another.

Since mosquitoes are less active during the fall's cooler temperatures, the current risk of transmission is “very low," said state Health Commissioner James McDonald.

Chikungunya is found mostly in tropical and subtropical regions, according to the state health department. Its symptoms include fever and joint pain, headache, muscle pain, joint swelling and rashes.

The illness is rarely fatal and most patients recover within a week, though newborns, older adults and people with chronic health conditions such as high blood pressure and diabetes are at higher risk, the agency said.

The U.S. and its territories have not seen a locally acquired case of the virus since 2019.

New York State has had three other cases of the virus this year, though all were linked to international travel to regions where the virus is prevalent, state health officials said.

Local mosquitoes can transmit other dangerous viruses, such as West Nile, Eastern Equine Encephalitis and Jamestown Canyon viruses.