The European Centre for Disease Control and Prevention said on Friday that an outbreak of chikungunya was reported in December for the first time from the Americas in the French section of Saint Martin.
In December, the ECDC said the risk of the disease spreading to other islands was high, and new cases have since been reported on other islands. As of Thursday, Saint Martin had reported 203 cases either confirmed or probable. Martinique reported 28 cases, Saint Barthélemy reported 25 cases, Guadeloupe reported 10 cases and one case was confirmed in Martinique in French Guiana.
The disease was detected during a recent dengue outbreak. The two viruses are transmitted by the same Aedes aegypti mosquito. Officials expect the number of cases to increase and the disease to spread as people travel between islands.
"Onward transmission in the EU from imported cases during the winter season is not to be expected, but vigilance during the mosquito season is required, as the possibility of autochthonous transmission of tropical mosquito-transmitted viruses in continental Europe does exist," The ECDC said in a risk assessment.
Symptoms of chikungunya include fever, headache, fatigue, nausea, vomiting, muscle pain, rash and joint pain. A vaccine is not available for the disease, and there is no specific treatment.
The symptoms for dengue are similar, and include bleeding from the gums or nose and easy bruising.