An outbreak of chikungunya in the Caribbean region was reported from the French part of the island of Saint Martin on 6 December 2013. It is the first time that autochthonous transmission of the virus has been documented in the Americas.
An ECDC risk assessment of the outbreak published on 12 December 2013 concluded that the risk of the disease spreading to other islands in the Caribbean region was high. Since then, autochthonous transmission and imported cases of chikungunya have been reported from several islands in the Caribbean.
The systematic laboratory confirmation of cases from the islands Saint Martin, Martinique, Saint Barthélemy and Guadeloupe was stopped because of the ongoing outbreak situation. As of 7 February 2014, the following number of cases have been reported:
- Saint Martin (FR): 601 probable or confirmed cases;
- Sint Maarten (NL): 60 confirmed cases;
- Saint Barthélemy: 83 probable or confirmed cases;
- Martinique: 518 probable or confirmed cases;
- Guadeloupe: 175 probable or confirmed cases;
- British Virgin Islands, Jost Van Dyke islands: six confirmed cases;
- Dominica: 3 confirmed cases and 1 imported confirmed case probably originating from Saint Martin.
Islands and countries from where imported cases were reported:
- French Guiana: 4 confirmed imported cases: 3 from Martinique and 1 from Saint Martin, with no evidence of local transmission;
- One imported confirmed case on the Island of Anguilla probably originating from Saint Martin;
- One imported case reported on the Island Aruba.
This overview indicates that the chikungunya outbreak in the Caribbean is still ongoing and spreading.
The chikungunya transmission was detected during an ongoing dengue outbreak in the Caribbean. Both arboviruses are transmitted by the same Aedes aegypti mosquito species. The naïve population, the presence of an effective vector in the region and the movement of people in and between islands are factors that make it likely that the outbreak will continue to spread geographically and increase in numbers.
The conclusions and recommendations of the rapid risk assessment published on 12 December 2013 remain valid.
Clinicians and travel medicine clinics should remain vigilant regarding imported dengue and chikungunya cases from the Caribbean.