Tiger mosquitoes - which can carry diseases including dengue fever, chikungunya and Zika - are now established across most of mainland France, and health authorities are urging the public to help stop their spread.
They remain most common in the south, but are also found in parts of the north and east, including the Paris region. They are most active from May to November.
They are identifiable by their black-and-white striped bodies (hence their ‘tiger’ name). Unlike many other mosquito species, they tend to be more active during the day and are smaller, measuring less than 5mm long.
They can transmit viruses including dengue, Zika, chikungunya and West Nile virus. Health authorities say 2025 saw an unprecedented number of chikungunya cases in mainland France, with 81 local transmission clusters and around 809 locally transmitted cases identified.
By comparison, 30 locally transmitted dengue cases and 60 confirmed West Nile virus infections were recorded in mainland France in 2025.
For the first time, locally transmitted chikungunya cases were also detected in Bourgogne-Franche-Comté, Grand Est and Nouvelle-Aquitaine, while West Nile virus cases were identified in Ile-de-France, Auvergne-Rhône-Alpes and Normandy.
Most locally transmitted cases begin with a traveller infected abroad or in an overseas territory returning to mainland France, where local tiger mosquitoes can then spread the virus to others.
Officials say the increase in imported cases is linked in part to outbreaks in overseas territories and internationally, particularly in the Indian Ocean region including Réunion.
Advice to stop the mosquito and virus spread
The Health Ministry states that “the fight against viruses transmitted by the tiger mosquito is everyone's business”, and has outlined several actions people can take to help reduce the insect’s spread.
“No single measure is 100% effective; it is the sum of all these individual and collective measures that makes it possible to reduce the spread,” it states.
Reducing larval breeding sites is considered the most effective way to stop mosquitoes spreading. This means removing stagnant water in and around homes and gardens, including in pots, buckets, tarpaulins and gutters.
People are also advised to:
Wear long, loose-fitting clothing
Use repellents and install mosquito nets
Remove fallen fruit and garden debris
Prune and maintain hedges and trees
Regularly empty pet water bowls, particularly after rainfall
Protect themselves against mosquito bites, particularly in areas where these diseases are circulating
Continue protecting themselves against mosquito bites for three weeks after returning to France to reduce the risk of transmission.
Dengue and chikungunya can often present without symptoms, although some cases can become serious. Consult a doctor and mention any recent travel if you notice:
Fever
Headaches
Joint and muscle pain
Skin rash
Conjunctivitis
You can check which countries present a significant risk on the travel advice pages of the France Diplomatie website.
People can also help track the spread of tiger mosquitoes.
If you believe you have seen a tiger mosquito in a department where it has not previously been reported, you can report it via the government’s dedicated online portal.
How do I know if I have been bitten?
Signs of a tiger mosquito bite can include:
Itching shortly after the bite, which intensifies for several minutes
A small, slightly flat blister measuring between 5mm and 2cm in diameter
A pale area around the bite with a red halo that may spread
A bite that feels hard, warm or painful
Itching that comes and goes
If you believe you have been bitten and begin to experience symptoms of a virus, consult a doctor as soon as possible.
