An African mosquito-bred virus by the name of “chikungunya” has been confirmed in two cases in the French part of the Caribbean isle of Saint Martin, located off the eastern coast of Puerto Rico, and situated between North and South America.

The World Health Organization (WHO) was notified on Dec. 6 that the island had identified two cases of the disease, which had previously only been found in Africa. Health officials recently released a Global Alert notifying people that a disease outbreak may be imminent. “This is the first time that locally acquired transmission of chikungunya has been detected in the WHO Americas Region,” the WHO said in a statement.

According to the report, there were five cases of joint pain and fever on Nov. 18. The health officials ruled out dengue fever, which has had an outbreak on St. Martin since January of this year. As of Dec. 10, the WHO states that “two confirmed, four probable, and twenty suspected cases of chikungunya infection have been reported.”

Chikungunya is rarely fatal and typically spread to humans through mosquito bites. Fever, headaches, and joint pain — especially in the ankles and wrists — are common features of the disease.

Scientists discovered chikungunya in Tanzania in 1955, and since then it has mainly been found in sub-Saharan Africa as well as southern Asia. In 2006, India saw a massive outbreak, with over a million people sickened. Shortly after this, the virus was carried to Italy, where it mutated — instead of being transmitted by the mosquito Aedes aegypti, it began to spread via the Asian tiger mosquito, which can tolerate more moderate environments. This has made it more likely to spread in the Americas, as the tiger mosquito are found in the southern U.S. and even in some parts of the north.

The name chikungunya means “that which bends up” in Makonde, the language spoken by an ethnic group located in Tanzania and Mozambique in Africa. Chikungunya refers to the position and physique of people infected with the virus, as they may "bend over" in pain.

Because there is no vaccine for the disease, the WHO says that the best way to prevent an outbreak is to raise awareness of the risk factors, as well as finding ways to halt mosquito proliferation. “The health authorities on both the French and the Dutch side of the island are cooperating closely to respond to this outbreak, in close coordination with public health authorities in France and the Netherlands,” the WHO stated.