Regional health authorities have warned of a possible epidemic of dengue fever in the French Caribbean archipelago of Guadeloupe, where more than 425 cases have been reported since the beginning of the year.
Guadeloupe's regional health authority said that cases of dengue fever have been rising weekly since April, with the increase accelerating in recent weeks.
Since June alone, the mosquito-borne illness has been confirmed in 13 different municipalities in the region.
An uptick in travel and crowds due to festivals and the summer holidays, combined with hurricane season, are all reasons to fear "the disease spreading throughout the territory and an epidemic of dengue", the Guadeloupe Regional Health Agency said in its 13 July statement.
Dengue has been resurging on the archipelago since November 2022. Of 32 municipalities on the islands, only six have not had a case confirmed since January 2023, according to the latest update from France's Health Surveillance Institute.
Other French Caribbean territories are less affected, the institute said, with 200 cases in Martinique since the beginning of the year and only sporadic cases on the small islands of Saint-Martin and Saint-Barthélemy.
But nearly a quarter of all cases on Martinique were detected since mid-June, suggesting that infections are accelerating there too.
"A few dozen" cases of dengue have been reported in mainland France linked to people who had recently travelled to the Caribbean, the institute said.
Growing threat
Countries in Central America and the Caribbean are expected to see heavy rainfall in the second half of 2023, which may further fuel the spread of dengue by providing more breeding grounds for mosquitos, the Pan-American Health Organization and World Health Organization warned at the start of July.
Climate change is forecast to increase the risk of dengue and other diseases spread by mosquitos, as rains, temperature and humidity increase and favour the conditions for transmission, even in parts of the world that didn't used to be affected.
The type of mosquito that spreads dengue is now widespread in parts of Europe, including France, which now reports more locally transmitted infections than any other country in the EU.
Infection with the dengue virus usually produces no or mild symptoms, but some people suffer from fever, headache, aches, nausea and rashes. In the worst cases, it can be fatal.
While a vaccine was approved by the EU last year, it is not yet widely available and the easiest way to prevent dengue remains by taking measures against mosquito bites, such as using repellents and throwing out standing water that may be harbouring larvae.