Â鶹´«Ã½Ó³»­

The first native case of dengue fever in mainland France of 2025 has been confirmed by health officials.

The infected patient was recorded in the Loire department of the Auvergne-Rhône-Alpes region in eastern France, Santé Publique France states in its weekly published yesterday (July 9).

The Agence Regional Santé (ARS) in the area had received reports of a suspected case on July 4 after a person in the Saint-Chamond area began exhibiting symptoms at the start of the month.

Doctors in France are required to report suspected cases of the disease to regional health authorities due to its potential severity and risk of widespread infection.

The confirmation follows more than a dozen native cases of chikungunya in recent weeks in mainland France, and more than a thousand imported cases of both diseases since the start of 2025, largely due to an outbreak of chikungunya in the overseas department of Réunion.

A ‘native’ case of either disease is one in which the infected person has not travelled outside of France in the last two weeks, meaning it was picked up in the country. Both diseases are spread by tiger mosquitoes. 

Tiger mosquitoes are now prevalent in all regions of mainland France, but mostly concentrated in the south and centre/east. 

Warmer temperatures are in part responsible for the spread as tiger mosquitoes thrive in hotter conditions.

Dengue fever is not spread by human transmission (except through blood mixing, organ donation or vertical transmission during pregnancy) or through any other animal.

Symptoms of the disease include high fever, headache, vomiting, muscle and joint pains, as well as irritable, itchy skin and rashes. 

There have been 48 native cases of dengue fever recorded in mainland France since 2010. 

Control operations taking place

Health officials conducted a ‘mosquito control operation’ in the Saint-Chamond area of the Loire last night in an attempt to remove the mosquito population carrying the disease.

Authorities will conduct door-to-door visits today to homes in the area to identify residents who have or have had symptoms suggestive of dengue fever, the ARS said. 

Those in the area who are not contacted should not worry, as it means they are not within the vicinity of the infected mosquito population. 

Mosquitoes do not travel far during their life span, remaining within a few hundred feet of where they hatch. 

However, the number of native cases means residents in France should be on alert and remove any potential mosquito breeding grounds. 

This mostly consists of bodies of stagnant water, such as tyres and plant pots (which should be regularly checked), unused swimming pools and ponds, as well as gutters and on roofs. 

Mosquito traps can be used, and in some cases are offered by local mairies in an attempt to reduce the local population.

More information on how to combat tiger mosquitoes can be found in our article here.