Country surveillance profile
Mosquito-borne disease in France, 2025-2026 data
As of 27 July 2026, Mosticare tracks France surveillance for West Nile virus, Chikungunya and Dengue. France had the largest autochthonous chikungunya outbreak in continental Europe in 2025, 809 locally-acquired cases across 79 transmission episodes (1 May, 30 November), with symptom onset between 27 May and 13 November. In 2026 it has reported 1 West Nile virus case, 2 Dengue cases year-to-date. Each figure cites the responsible national or EU authority.
Last updated · 27 July 2026 · CC BY 4.0
Key facts
France had the largest autochthonous chikungunya outbreak in continental Europe in 2025, 809 locally-acquired cases across 79 transmission episodes (1 May, 30 November), with symptom onset between 27 May and 13 November. It was the largest continental-European autochthonous CHIKV outbreak on record for that year.
Source: Santé publique France · enhanced arbovirus surveillance · verified 25 May 2026
The first 2026 autochthonous (locally acquired) human West Nile virus case in metropolitan France was reported in the Pyrénées-Orientales département (Occitanie). Santé publique France's national reinforced arbovirus bulletin of 23 July 2026 (data to 20 July 2026) recorded 1 locally-acquired human WNV case there, 0 deaths, the first of the metropolitan-France 2026 season. It is SpF-sourced and not yet reflected in the ECDC weekly WNV report (which at Week 29, data to 15 July 2026, lists Italy 21, Greece 7, North Macedonia 2, Romania 2 and Spain 2); France would become the sixth ECDC-reporting country when the case is picked up. WNV is transmitted by Culex mosquitoes; most human infections are silent, and there is no licensed human vaccine or specific antiviral, so avoiding bites is the primary individual defence.
Source: Santé publique France · national reinforced arbovirus bulletin (chikungunya-dengue-Zika et-17, 23 July 2026, data to 20 July 2026) · verified 27 July 2026
The first 2026 autochthonous (locally acquired) dengue in metropolitan France was detected in Occitanie, 2 cases, one in the Tarn and one in l'Hérault. Santé publique France's national reinforced arbovirus bulletin of 23 July 2026 (data to 20 July 2026) recorded them as the first metropolitan-France autochthonous dengue of the year, 0 deaths. Transmission is by the Aedes albopictus tiger mosquito, established across much of southern and central metropolitan France; the same bulletin reported 231 imported dengue cases for 1 May to 19 July 2026, the travel-associated reservoir that can seed local transmission. Dengue mosquitoes bite mainly by day, so personal protection and physical barriers are the primary individual defence.
Source: Santé publique France · national reinforced arbovirus bulletin (chikungunya-dengue-Zika et-17, 23 July 2026, data to 20 July 2026) · verified 27 July 2026
The data
| Country / region | Disease | Cases | Deaths | Period | Source | Updated |
|---|---|---|---|---|---|---|
| France · Tarn + l'Hérault (Occitanie) | Dengue | 2 | 0 | 2026 enhanced-surveillance period (1 May, 30 November) | Santé publique France · national reinforced arbovirus bulletin (chikungunya-dengue-Zika et-17, 23 July 2026) | 27 July 2026 |
| France · Pyrénées-Orientales (Occitanie) | West Nile virus | 1 | 0 | 2026 transmission season (year-to-date) | Santé publique France · national reinforced arbovirus bulletin (chikungunya-dengue-Zika et-17, 23 July 2026) | 27 July 2026 |
| France | Chikungunya | 0 | 0 | 2026 enhanced-surveillance period (1 May, 30 November) | Santé publique France · enhanced arbovirus surveillance | 31 May 2026 |
| France | Chikungunya | 809 | , | 2025 enhanced-surveillance period (1 May, 30 November) | Santé publique France, bilan national chikungunya/dengue/Zika 2025 (édition nationale, enhanced arbovirus surveillance) | 15 June 2026 |
| France | West Nile virus | 62 | 5 | 2025 transmission season | Santé publique France, bilan national West Nile 2025 (édition nationale, deaths); ECDC for the cross-country case count (data to 3 Dec 2025) | 15 June 2026 |
About surveillance in France
France runs year-round West Nile virus surveillance and an enhanced arbovirus programme (1 May, 30 November) for chikungunya and dengue, led by Santé publique France. In 2025 metropolitan France recorded the largest autochthonous chikungunya outbreak in continental Europe.
Frequently asked questions
What mosquito-borne diseases is France monitoring in 2026?
Mosticare tracks France surveillance for West Nile virus, Chikungunya and Dengue, each sourced to the responsible national authority or ECDC.
What was the largest chikungunya outbreak in Europe in 2025?
France had the largest autochthonous chikungunya outbreak in continental Europe in 2025, 809 locally-acquired cases across 79 transmission episodes (1 May, 30 November), with symptom onset between 27 May and 13 November. It was the largest continental-European autochthonous CHIKV outbreak on record for that year.
Where was the first locally acquired West Nile virus case in metropolitan France in 2026?
The first 2026 autochthonous (locally acquired) human West Nile virus case in metropolitan France was reported in the Pyrénées-Orientales département (Occitanie). Santé publique France's national reinforced arbovirus bulletin of 23 July 2026 (data to 20 July 2026) recorded 1 locally-acquired human WNV case there, 0 deaths, the first of the metropolitan-France 2026 season. It is SpF-sourced and not yet reflected in the ECDC weekly WNV report (which at Week 29, data to 15 July 2026, lists Italy 21, Greece 7, North Macedonia 2, Romania 2 and Spain 2); France would become the sixth ECDC-reporting country when the case is picked up. WNV is transmitted by Culex mosquitoes; most human infections are silent, and there is no licensed human vaccine or specific antiviral, so avoiding bites is the primary individual defence.
Where was the first locally acquired dengue case in metropolitan France in 2026?
The first 2026 autochthonous (locally acquired) dengue in metropolitan France was detected in Occitanie, 2 cases, one in the Tarn and one in l'Hérault. Santé publique France's national reinforced arbovirus bulletin of 23 July 2026 (data to 20 July 2026) recorded them as the first metropolitan-France autochthonous dengue of the year, 0 deaths. Transmission is by the Aedes albopictus tiger mosquito, established across much of southern and central metropolitan France; the same bulletin reported 231 imported dengue cases for 1 May to 19 July 2026, the travel-associated reservoir that can seed local transmission. Dengue mosquitoes bite mainly by day, so personal protection and physical barriers are the primary individual defence.
How many West Nile virus cases did France report in 2025?
France reported 62 West Nile virus cases and 5 deaths in 2025 (2025 transmission season), per Santé publique France, bilan national West Nile 2025 (édition nationale, deaths); ECDC for the cross-country case count (data to 3 Dec 2025).
How many Chikungunya cases did France report in 2025?
France reported 809 Chikungunya cases in 2025 (2025 enhanced-surveillance period (1 May, 30 November)), per Santé publique France, bilan national chikungunya/dengue/Zika 2025 (édition nationale, enhanced arbovirus surveillance).
Sources
- Santé publique France, bilan national West Nile 2025 (édition nationale, deaths); ECDC for the cross-country case count (data to 3 Dec 2025)
- Santé publique France, bilan national chikungunya/dengue/Zika 2025 (édition nationale, enhanced arbovirus surveillance)
- Santé publique France · national reinforced arbovirus bulletin (chikungunya-dengue-Zika et-17, 23 July 2026)
- Santé publique France · enhanced arbovirus surveillance
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About this data
Mosticare aggregates and re-publishes vector-borne disease surveillance from ECDC, EFSA, and national ministries of health. Mosticare is an aggregator, not a primary surveillance authority, every figure on this page cites the originating source and is independently verifiable. This is a partial aggregation; for the complete EU/EEA totals, ECDC is the primary source.
The data behind this page is published as free, machine-readable feeds under CC BY 4.0, the point-in-time incidence snapshot at /threat-map/feed.json (JSON Schema) and the multi-year trends at /threat-map/feed/trends.json (JSON Schema). See the live Europe threat map and the full data room.