According to officials, there are three confirmed cases of the Chikungunya virus on Long Island. The three residents returned from the Caribbean recently where it is said they contracted the mosquito-borne illness.

An estimated 357 people in the United States have been infected with the Chikungunya virus after traveling to regions where it's an epidemic. However, U.S. health officials announced on Friday that the first locally diagnosed cases were documented in Florida after a man and woman became infected and hadn't traveled anywhere. The virus has surfaced in 21 Caribbean countries/islands, affecting over 355,000 people and killing 21.

Doctors at the North Shore University Hospital in Manhasset said that the three Long Island patients returned from the Caribbean in recent weeks and were already sickened by the virus. Dr. David Hirschwerk, a specialist in infectious diseases and associate chairman of medicine, said that these patients are unrelated to the local Florida case.

"One of those cases has been confirmed by the CDC and testing is still pending on the others," said Dr. Hirschwerk, in this Fox News article. "The likelihood of having more cases in individuals who have not traveled is very low. The Florida case is unusual, and I don't expect to see high numbers [of infections], but we have to keep an eye on the situation."

According to the Centers for Disease Control and Prevention, the Chikungunya virus is characterized by fever and joint pain. Other symptoms may include headache, muscle pain, joint swelling, or rash. The virus is endemic in Africa, Asia, and the Indian and Pacific Oceans, while outbreaks have occurred in Europe. It first surfaced in the Caribbean in 2013 and has been an epidemic ever since. Just like the West Nile and Eastern Equine Encephalitis (EEE) viruses, there is no treatment or cure for Chikungunya so all health officials can do is recommend travelers and/or residents living amongst mosquito-populated areas to wear long sleeves and pants and use insect repellant.

The two species of Aedes mosquitoes that spread Chikungunya are located in the southern and eastern United States, so the potential of an outbreak remains if people in those regions travel to the Caribbean and return infected. The CDC provides a list for preventing mosquito bites as well as mitigating the insect's presence near homes. You can read more about the Long Island patients in this Newsday article.