Dengue and chikungunya in France 2025: 30 autochthonous dengue cases, 809 chikungunya cases — what it means for summer 2026

On 6 May 2026, Santé publique France published its 2025 report on arbovirus surveillance in metropolitan France (chikungunya, dengue, Zika). The findings are clear: the 2025 season was historic for chikungunya with 809 autochthonous cases — a record since 2006 — and dengue continued to establish itself locally with 30 autochthonous cases identified. For the Paris region and more broadly for everyone preparing for summer 2026, this report is not just another statistic: it changes the way you need to protect yourself, at home and while travelling.

What the 2025 report says

The national bulletin « Chikungunya, dengue et Zika en France hexagonale. Bilan 2025 » covers the enhanced surveillance period from 1 May to 30 November 2025. Three numbers should be remembered:

• 30 autochthonous dengue cases identified, spread across 11 transmission episodes (from 1 to 10 cases per episode), plus 1 isolated case whose place of contamination could not be established;
• 809 autochthonous chikungunya cases and 79 transmission episodes, an unprecedented figure since surveillance began in 2006;
• 81 metropolitan departments had at least one municipality colonised by the tiger mosquito (Aedes albopictus) on 1 January 2025, i.e. around 49 % of the French population exposed.

The first dengue autochthonous symptoms ranged from 25 June to 14 September 2025, with a median episode duration of 12 days (2 to 82 days depending on the cluster). This timeline matters: it shows that the « risk window » opens early in the summer, well before the August heatwave.

Why 2025 was a historic year

The chikungunya surge is explained by the major epidemic that hit La Réunion in the Indian Ocean in 2024-2025, caused by an ECSA-2 strain carrying the E1-226V mutation, particularly well adapted to the tiger mosquito. Travellers contaminated in La Réunion were then bitten in metropolitan France, triggering local transmission chains in the south of the country. Santé publique France identifies 79 distinct episodes, with some highly clustered foci (one single episode gathered 10 cases in Aubagne, Bouches-du-Rhône).

For dengue, the progression is slower but steady: 30 autochthonous cases in 2025, against fewer than ten in previous years, and for the first time an episode identified in Nouvelle-Aquitaine (Langon, Gironde, 3 cases). Serotypes DENV-1, DENV-2 and DENV-3 all circulated, a sign that the tiger mosquito is now a competent vector for several viral strains.

« 809 autochthonous chikungunya cases in 2025, a record since surveillance was set up in 2006. » — Santé publique France, bulletin of 6 May 2026.

INRAE also confirmed in 2024 for the first time the presence of the dengue virus directly in tiger mosquitoes captured in metropolitan France (Drôme cluster, summer 2023), validating the role of Aedes albopictus as a vector on the national territory.

The 2025 map of dengue episodes

The regional report published by Santé publique France details the geography of these 11 autochthonous dengue episodes:

• Provence-Alpes-Côte d'Azur: 3 episodes, 16 cases — notably Aubagne (10 cases) and Rognac (5 cases);
• Occitanie: 5 episodes, 6 cases;
• Auvergne-Rhône-Alpes: 2 episodes, 4 cases;
• Nouvelle-Aquitaine: 1 episode of 3 cases in Langon (Gironde), a first for the region.

The primary imported cases (at the origin of 6 of the 11 episodes) came from French Polynesia (3), Martinique (1), Thailand (1) and Fiji (1). In other words, every traveller contaminated in the tropics who returns to metropolitan France during the tiger mosquito activity season can, in theory, be at the origin of a local cluster. The Paris region did not experience an autochthonous dengue episode in 2025, but its massive colonisation by the tiger mosquito and its population density make it an area where the next local transmission is plausible.

Standing water in a flowerpot saucer: the tiger mosquito's main breeding site in urban areas

The Paris region, the next at-risk area?

The Paris region ticks almost every box for a local transmission area:

• Long-standing, stable colonisation: the tiger mosquito has been established in the inner suburbs since the mid-2010s and is spreading towards the outer suburbs;
• Population density: more than 12 million inhabitants, a large share of whom travel to tropical areas (Caribbean, Indian Ocean, South-East Asia);
• Returning travel: Roissy-Charles-de-Gaulle is France's leading airport platform for flights from endemic areas;
• Urban climate: heat islands, balconies and rooftop terraces multiply larval breeding sites in summer.

The risk is therefore no longer theoretical. The feared scenario is a dengue cluster declared in summer after the arrival of a viraemic traveller: if a local tiger mosquito bites them in the days that follow, it becomes a vector itself and can transmit the virus to other people bitten within a few hundred metres.

To limit this risk, the ARS Île-de-France and mosquito-control operators carry out targeted operations every year around suspected cases (perimeter of 150 to 200 metres), with adulticide spraying and treatment of larval breeding sites. This is the system that will be activated in the event of a report this summer.

The right reflexes to adopt right now

The tiger mosquito is a daytime and urban mosquito, which bites mainly outside homes, early in the morning and at the end of the day. Its lifespan is short (3 to 4 weeks) but a stagnant water puddle the size of a bottle cap is enough for a female to lay between 50 and 200 eggs. These eggs resist desiccation for several months and hatch at the first warm rains. This is why combating larval breeding sites is the most effective measure.

Here are the six priority actions to put in place at and around your home:

1. Empty once a week all saucers, watering cans, buckets, children's toys and any container likely to hold water.
2. Cover water reservoirs (tanks, cisterns, recovery trays) with a mosquito net or a hermetic lid.
3. Maintain gutters, manholes, floor traps and drain covers: a simple flush removes standing water.
4. Remove used tyres, tarpaulins, wheelbarrows, upturned toys and any object that can act as a reservoir.
5. Trim dense vegetation regularly, as tiger mosquitoes rest in hedges and bushes less than one metre off the ground.
6. Install mosquito nets on windows, especially in children's bedrooms, and use a skin repellent approved for use (DEET 30-50 %, icaridin 20 %, IR3535) in addition to long clothing during biting hours.

For people particularly exposed — pregnant women, elderly people, immunocompromised patients or people living within a mosquito-control operation perimeter — the ARS recommends seeing a doctor in case of sudden fever, intense joint pain or skin rash within 7 to 14 days after a trip to a tropical area or a bite in France.

ProDeratisation's role in the Paris region

Our anti-mosquito service operates across the whole Paris region for individuals, co-ownerships, restaurateurs and park and garden managers. We offer:

• a larval breeding site diagnosis on your property (balcony, garden, building courtyard);
• the installation of sentinel ovitraps that detect the presence of the tiger mosquito ahead of bites;
• targeted larvicide treatments (Bacillus thuringiensis israelensis — Bti), compatible with pets and children;
• administrative support in case of an ARS report: intervention report, mapping, advice on perimeter mosquito-control operations.

For large-scale operations (campsites, outdoor hotels, leisure bases, outdoor events), we work in coordination with operators approved by the Entente de démoustication (EID).

You can consult our pricing or get an instant quote through our free estimate. For urgent situations — ongoing ARS report, mosquito-control perimeter activated in your neighbourhood, event to be protected within 48 hours — our emergency page puts you in touch with a technician 7 days a week.

Travelling this summer: what you need to know

The 2025 report insists that 6 of the 11 autochthonous dengue episodes are linked to a traveller who returned contaminated from French Polynesia, Martinique, Thailand or Fiji. The rule is simple: a traveller who develops a fever within 7 days of returning from a tropical area should see a doctor quickly, report their travel to their doctor, and protect themselves from mosquito bites (repellent, long clothing, mosquito net) for the 7 days following their return to avoid contaminating a local mosquito.

For at-risk destinations (Caribbean, French Guiana, La Réunion, Mayotte, South-East Asia, Latin America, East Africa), the ARS and Santé publique France recommend a pre-travel consultation with your doctor or at an international vaccination centre, with vaccination updates (yellow fever in particular) and prescription of a suitable repellent.

What to remember for summer 2026

The 2025 report published on 6 May 2026 by Santé publique France is not designed to raise alarm for the sake of it. It draws up a lucid snapshot: metropolitan France is no longer spared from diseases transmitted by the tiger mosquito, and the risk of a local dengue or chikungunya cluster increases as new departments are colonised. The Paris region, already colonised and densely populated, is an area where individual and collective vigilance pays off: eliminate larval breeding sites, protect yourself from bites outdoors, report any suspected tiger mosquito via the signalement-moustique.fr platform.

If you notice an abnormal proliferation of tiger mosquitoes on your balcony, in your building courtyard or around your business, ProDeratisation operates across the whole Paris region with a free diagnosis and a tailored action plan. Contact us or consult our anti-mosquito service to prepare for a peaceful summer.