A person living in New York has tested positive for the chikungunya virus, and it’s the first locally acquired case reported in the United States in six years, the New York State Department of Health confirmed Tuesday.

What did state health officials say about disease-infected regions?

Health officials said the mosquito-borne illness has been spreading in China and other regions, leading to one confirmed case in a Nassau County resident on Long Island. Laboratory testing was conducted at the state Department of Health’s Wadsworth Center, NBC News and ABC News reported.

“An investigation suggests that the individual likely contracted the virus following a bite from an infected mosquito,” officials said, per ABC News. “While the case is classified as locally acquired based on current information, the precise source of exposure is not known.”

County health officials also stated that the individual began experiencing symptoms in August after traveling outside the region but not outside the country. The person’s identity remains unknown, according to NBC News.

How can the chikungunya virus spread to others?

The Aedes albopictus mosquito, which can transmit chikungunya, is present in parts of the New York City metropolitan area and suburban Long Island, health officials said. The virus can spread when a mosquito bites an infected person and then transmits it to others.

Despite that, the disease cannot be spread directly from person to person, and the risk to the public remains low, according to ABC News and NBC News.

Chikungunya is most common in tropical and subtropical regions. Symptoms include fever, joint pain, headache, muscle pain, joint swelling or rash, the state health department said.

Certain vulnerable groups are most at risk for severe disease

The illness is rarely fatal, and most patients recover within a week, though some may experience lingering joint pain, officials said.

“People at higher risk for severe disease include newborns infected around the time of birth, adults aged 65 and older, and individuals with chronic conditions such as high blood pressure, diabetes or heart disease,” the New York State Department of Health stated, per ABC News.

“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,” Dr. James McDonald, state health commissioner, said, according to ABC News. “We urge everyone to take simple precautions to protect themselves and their families from mosquito bites.”

This is the first locally acquired case of the disease reported in the U.S. since 2019. There were three other confirmed cases this year outside the New York City region. According to state health officials, those people had traveled to international regions where active chikungunya infections are found, ABC News reported.