Record number of dengue fever cases reported in France

There have been more cases already this year than for the whole of 2023

All of the cases reported have come from abroad so far, records show, although there have been increased ‘native’ cases in recent years

Record cases of dengue fever have been reported in metropolitan France since the start of 2024, with more cases already reported this year than in the whole of 2023.

Figures show that there have been 2,166 reports of imported cases of the fever so far (from January 1 to April 30), compared to 2,019 for the whole of 2023, which was itself a record year.

This is more than 16 times the number of cases reported per year on average over the past five years (128 cases).

Most of these new cases were reported in people who had travelled to the overseas territories of the Antilles. There is currently an epidemic in the Americas and Caribbean.

This is what makes the cases ‘imported’; they came into France from people who had travelled to areas that are normally considered high-risk for dengue, rather than becoming infected on French soil (‘native’ cases).

Figures from Santé publique France show that 82% of imported cases in France were contracted in Martinique or Guadeloupe, while 5% came from French Guiana.

As a result, from May 1 to 14, the disease and its mosquito vectors have been under ‘reinforced surveillance’ by health authorities. Over this period alone, 98 more cases of imported dengue were identified.

Dengue is spread by bites from infected tiger mosquitoes, and is not transmitted between humans directly. It is usually benign, but can - in 1% of cases - cause haemorrhage and fatalities.

Tiger mosquitoes also spread viruses such as zika and chikungunya, but so far only five and two cases of these respectively have been reported in France since the start of 2024.

Read also: Latest on tiger mosquitoes in France: where, what risk and what to do 

‘Native’ dengue cases

Cases of ‘native’ dengue - infections on French soil - also saw a rise last year, as tiger mosquito numbers increase and the insects spread. In 2022, there were 66 native cases (a record), and around 50 in 2023.

So far in 2024, no native cases of dengue have been recorded.

Tiger mosquitoes - which are smaller than ‘regular’ mosquitoes, do not ‘buzz’, and tend to bite in the morning and evening rather than at night - are now present in all regions of mainland France. 

Read also: Tiger mosquitoes now in Normandy, last region of France to escape them 
Read also: Act now to limit tiger mosquitoes at French home this summer 

They were first reported in France in the south in 2004, and have managed to spread partly as a result of global warming and higher temperatures. They are active from May to November, and proliferate around areas of stagnant water.

People are warned to get rid of stagnant water wherever possible - including in drains and plant pots - and to use insect repellent and traps to avoid the mosquitoes.

What are the symptoms of dengue fever?

Most people who get dengue fever will show no symptoms. For those who do show symptoms, the most common are similar to flu, and include a fever, headache, muscle aches, nausea and a rash.

Symptoms typically appear four to seven days after the person is bitten.

If you have recently travelled to an at-risk area, or recently been bitten by a mosquito, and you begin to get symptoms, you are advised to report it to a GP and let them know your concerns as soon as possible.