Many cases of dengue have been imported into mainland France for several months. We take stock of the situation but also the symptoms to be monitored and the prevention measures.
It’s not just chikungunya. Many cases of dengue have been detected in mainland France for several months. According to the latest public health report France published on June 25, 2025, more than 1,550 cases have been detected since the start of the year, including more than 450 only in early May and end of June. These are mostly imported cases of Guadeloupe, Martinique and French Polynesia, since the virus is mainly raging in tropical areas. If the number of cases is worrying, is far from the 2024 record, with nearly 4,700 cases in mainland France.
How is dengue transmit?
Dengue, like chikungunya, is transmitted through mosquitoes. The virus “is transmitted to humans during a bite by mosquitoes of the genre Aedes, mostly Aedes aegypti; but also sometimes the tiger mosquito (Aedes albopictus). When a mosquito feeds on the blood of an infected person, the mosquito can then contaminate other people “, according to the Pasteur Institute. In some rare cases, dengue can also be transmitted from a pregnant woman to her baby or even during a transfusion.
Unlike chikungunya, there are several strains of the virus and it is therefore possible to be infected several times by dengue. A new infection even increases “the risk of developing severe dengue”, according to the Pasteur Institute.
What are the symptoms of dengue?
In the majority of cases, dengue is asymptomatic, or manifests itself in slight symptoms. In infected people, after 4 to 10 days on average the symptoms are: high fever, headache, nausea and vomiting, as well as joint and muscle pain. An eruption is also possible. “Symptoms persist two to seven days and the health of the infected person generally evolves favorably,” notes the Pasteur Institute.
But in some rare cases, a severe form of dengue, potentially fatal, occurs. It can cause severe abdominal pain, significant vomiting, hemorrhages, extreme tachycardia or even a failure of the organs. There is no specific dengue treatment, only symptomatic treatments.
How to protect yourself from dengue?
Unfortunately there is no specific means of prevention of dengue. No vaccine is available. “Individual prevention is therefore essentially based on the means of protection against mosquito bites: repellents in sprays or creams, serpentines, electric diffusers, long clothes, mosquito nets”, recalls Public Health France.
Prevention is also collective, and is based on the fight against tiger mosquitoes, in particular by eliminating stagnant water points, where the eggs of the insect can be laid.
