{ "$schema": "https://www.mosticare.org/threat-map/feed-trends.schema.json", "feed": "mosticare-disease-trends", "version": "1.1.0", "publisher": { "name": "Mosticare", "url": "https://www.mosticare.org", "type": "NGO" }, "description": "Machine-readable multi-year TREND feed for vector-borne diseases in Europe — the trend counterpart to Mosticare's point-in-time disease-incidence feed (/threat-map/feed.json). Each series carries the sourced year-by-year case totals, a derived summary (peak/trough/latest/mean and the honest 'is it increasing?' answer), and answer-bearing questions. Figures are reported locally-acquired (autochthonous) human cases per ECDC; year-to-year comparisons are affected by changes in surveillance and case definitions. Coverage today: West Nile virus (volatile, weather-driven), dengue (rising sharply since 2022) and chikungunya (episodic outbreak clusters that open and close, so its series is intentionally gappy). ECDC is the primary source for the complete European total — see each series' caveat.", "license": "CC BY 4.0", "license_url": "https://creativecommons.org/licenses/by/4.0/", "temporal_coverage": "2007-01-01/2025-12-31", "variables_measured": [ { "name": "EU/EEA locally-acquired cases", "description": "Reported locally-acquired (autochthonous) human cases in EU/EEA Member States for the year, per ECDC — the consistent metric ECDC's Annual Epidemiological Report trends year over year.", "unit": "cases" }, { "name": "EU/EEA deaths", "description": "Deaths among locally-acquired EU/EEA cases where ECDC published the figure for the year; null when not separately reported (never zero).", "unit": "deaths" }, { "name": "Wider-Europe locally-acquired cases", "description": "ECDC's wider 'Europe' (EU/EEA + EU-neighbouring countries) locally-acquired total where ECDC reported one; null otherwise. Today this is populated only for West Nile virus (2024–2025), where it is ECDC's headline figure of which the EU/EEA value is the Member-State subtotal. Autochthonous chikungunya and dengue have occurred only within EU Member States, so their EU/EEA count is already the European total.", "unit": "cases" } ], "measurement_technique": "Re-publication of ECDC's published annual / end-of-season West Nile virus, chikungunya and dengue surveillance totals (Annual Epidemiological Reports and ECDC's historical local-transmission data where they exist, otherwise ECDC's end-of-season epidemiological updates / Communicable Disease Threats Reports), restated on one consistent definition (EU/EEA locally-acquired human cases) across years. Mosticare does not perform primary case ascertainment; each year cites the originating ECDC source.", "is_based_on": [ { "name": "ECDC — West Nile virus Annual Epidemiological Reports", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data" }, { "name": "ECDC — West Nile virus historical surveillance data", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data/historical" }, { "name": "ECDC — Epidemiological updates, West Nile virus transmission season in Europe", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/west-nile-virus-infection" }, { "name": "ECDC — Chikungunya historical data on local transmission in the EU/EEA", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/infectious-disease-topics/chikungunya-virus-disease/surveillance-and-updates/local-transmission-previous-years" }, { "name": "ECDC — Dengue historical data on local transmission in the EU/EEA", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years" }, { "name": "ECDC — Communicable Disease Threats Reports (end-of-season chikungunya & dengue figures)", "authority": "European Centre for Disease Prevention and Control (ECDC)", "url": "https://www.ecdc.europa.eu/en/publications-data/communicable-disease-threats-report" } ], "refresh_cadence": { "minimum": "annually", "target": "annually", "next_review": "2026-12-15" }, "last_updated": "2026-06-15", "series_count": 3, "series": [ { "disease": "West Nile virus", "disease_code": "WNV", "region_scope": "EU/EEA", "metric": "Locally-acquired (autochthonous) human cases", "unit": "cases", "temporal_coverage": "2016-01-01/2025-12-31", "source_authority": "European Centre for Disease Prevention and Control (ECDC)", "caveat": "Figures are reported locally-acquired (autochthonous) human cases in EU/EEA Member States per ECDC. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and the set of reporting countries; West Nile virus activity is strongly driven by summer weather and varies sharply between seasons. ECDC is the primary surveillance authority for the complete European total.", "point_count": 10, "points": [ { "year": 2016, "eu_eea_cases": 225, "eu_eea_deaths": null, "all_europe_cases": 492, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/news-events/epidemiological-update-west-nile-virus-transmission-season-europe-2016", "source_authority": "ECDC · Epidemiological update, WNV transmission season in Europe 2016", "last_updated": "2026-06-14", "notes": "225 autochthonous human cases in the EU (Romania 93, Italy 76, Hungary 44, Austria 5, Spain 3, Bulgaria 2, Cyprus 1, Croatia 1). EU-neighbouring countries reported a further 267 (Russia, Israel, Serbia and others), for 492 across the wider region. No EU fatality count published in this update." }, { "year": 2017, "eu_eea_cases": 201, "eu_eea_deaths": 25, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/AER_for_2017-West-Nile-virus-infection.pdf", "source_authority": "ECDC · Annual Epidemiological Report for 2017 — West Nile virus infection", "last_updated": "2026-06-14", "notes": "201 locally-acquired EU/EEA cases (208 total including travel-related), 25 deaths (Romania 14, Greece 5, Hungary 4, Croatia 1, Italy 1). Case fatality among cases with known outcome ~12%." }, { "year": 2018, "eu_eea_cases": 1548, "eu_eea_deaths": 166, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/AER_for_2018-West-Nile-virus.pdf", "source_authority": "ECDC · Annual Epidemiological Report for 2018 — West Nile virus infection", "last_updated": "2026-06-14", "notes": "The peak European season on record: 1,548 locally-acquired EU/EEA cases and 166 deaths — roughly a sevenfold jump on 2017, which ECDC attributed to an exceptionally warm summer. (ECDC's later retrospectives cite ≈1,549; the 2018 AER Table 1 states 1,548.)" }, { "year": 2019, "eu_eea_cases": 425, "eu_eea_deaths": 52, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/AER-WNV-infection-2019.pdf", "source_authority": "ECDC · Annual Epidemiological Report for 2019 — West Nile virus infection", "last_updated": "2026-06-14", "notes": "425 locally-acquired EU/EEA cases (443 total including travel-related) across 11 Member States, 52 deaths (Greece 35, Romania 9, Italy 4, Hungary 2, Cyprus 1, Bulgaria 1)." }, { "year": 2020, "eu_eea_cases": 316, "eu_eea_deaths": 38, "all_europe_cases": 336, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/news-events/epidemiological-update-west-nile-virus-transmission-season-europe-2020", "source_authority": "ECDC · Epidemiological update, WNV transmission season in Europe 2020", "last_updated": "2026-06-14", "notes": "316 locally-acquired EU/EEA cases with known place of infection (Greece 143, Spain 77, Italy 66, Germany 13, Netherlands 7, Romania 6, Hungary 3, Bulgaria 1), 38 deaths. The wider European total (incl. Israel) was 336. The Netherlands recorded its first-ever human WNV cases." }, { "year": 2021, "eu_eea_cases": 141, "eu_eea_deaths": 10, "all_europe_cases": 159, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/news-events/epidemiological-update-west-nile-virus-transmission-season-europe-2021", "source_authority": "ECDC · Epidemiological update, WNV transmission season in Europe 2021", "last_updated": "2026-06-14", "notes": "141 locally-acquired EU/EEA cases (Greece 57, Italy 55, Hungary 7, Romania 7, Spain 6, Germany 4, Austria 3, plus 2 Greek cases with unknown NUTS3 place), 10 deaths. The lowest European season of the decade. Serbia added 18 cases for a wider total of 159." }, { "year": 2022, "eu_eea_cases": 1113, "eu_eea_deaths": 92, "all_europe_cases": 1340, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/news-events/epidemiological-update-west-nile-virus-transmission-season-europe-2022", "source_authority": "ECDC · Epidemiological update, WNV transmission season in Europe 2022", "last_updated": "2026-06-14", "notes": "1,113 locally-acquired EU/EEA cases (Italy 723, Greece 283, Romania 47 and seven more Member States), 92 deaths — the highest since 2018. Including EU-neighbouring countries (Serbia 226, North Macedonia) the wider European total was 1,340 with 104 deaths." }, { "year": 2023, "eu_eea_cases": 709, "eu_eea_deaths": 67, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data/historical", "source_authority": "ECDC · West Nile virus historical surveillance data (2023 season dataset)", "last_updated": "2026-06-14", "notes": "709 locally-acquired EU/EEA cases (728 total including travel-related) across nine Member States (Italy 336, Greece 162, Romania 103, France 43, Hungary 29, Spain 19, Germany 6, Croatia 6, Cyprus 5), 67 deaths." }, { "year": 2024, "eu_eea_cases": 1171, "eu_eea_deaths": 99, "all_europe_cases": 1436, "eu_eea_is_subtotal": true, "source_url": "https://www.ecdc.europa.eu/en/west-nile-fever/surveillance-and-disease-data/historical", "source_authority": "ECDC · West Nile virus end-of-season surveillance summary 2024 (data to 4 Dec 2024)", "last_updated": "2026-06-14", "notes": "ECDC's 2024 headline is a wider 'Europe' total of 1,436 locally-acquired cases and 125 deaths across 19 countries. The 1,171 here is the EU/EEA Member-State subtotal (Italy 455, Greece 217, Spain 138, Hungary 111, Romania 99 and nine more), with 99 deaths; the remaining 265 cases were in EU-neighbouring countries (Albania 106, Türkiye 90, Serbia 63, Kosovo 4, North Macedonia 2)." }, { "year": 2025, "eu_eea_cases": 1043, "eu_eea_deaths": null, "all_europe_cases": 1112, "eu_eea_is_subtotal": true, "source_url": "https://www.ecdc.europa.eu/en/west-nile-virus-infection", "source_authority": "ECDC · Surveillance of WNV in Europe, monthly report (data to 3 Dec 2025)", "last_updated": "2026-06-14", "notes": "ECDC's 2025 headline is a wider 'Europe' total of 1,112 locally-acquired cases and 97 deaths across 14 countries. The 1,043 here is the EU/EEA Member-State subtotal (Italy 779, Greece 96, France 62, Romania 49, Spain 36, Hungary 14, Croatia 4, Germany 2, Bulgaria 1); the other 69 cases were in EU-neighbouring countries (Serbia 62, Albania 3, North Macedonia 2, Kosovo 1, Türkiye 1). A per-country EU/EEA 2025 death subtotal is not published, so deaths is null here (the wider-Europe figure was 97)." } ], "summary": { "first_year": 2016, "last_year": 2025, "count": 10, "mean_cases": 689, "peak": { "year": 2018, "cases": 1548 }, "trough": { "year": 2021, "cases": 141 }, "latest": { "year": 2025, "cases": 1043 }, "recent_above_mean_years": [ 2022, 2023, 2024, 2025 ], "answer": "Reported West Nile virus cases in the EU/EEA swing sharply from one summer to the next rather than rising in a straight line. Between 2016 and 2025, EU/EEA Member States reported between 141 locally-acquired human cases (2021) and 1,548 (2018) a year, averaging about 689. Each of the last 4 seasons (2022–2025) has been above that 2016–2025 average, so the burden has been elevated and geographically wider in recent years — though 2018 remains the peak. Figures are reported locally-acquired (autochthonous) human cases in EU/EEA Member States per ECDC. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and the set of reporting countries; West Nile virus activity is strongly driven by summer weather and varies sharply between seasons. ECDC is the primary surveillance authority for the complete European total." }, "questions": [ { "question": "Is West Nile virus increasing in Europe?", "answer": "Reported West Nile virus cases in the EU/EEA swing sharply from one summer to the next rather than rising in a straight line. Between 2016 and 2025, EU/EEA Member States reported between 141 locally-acquired human cases (2021) and 1,548 (2018) a year, averaging about 689. Each of the last 4 seasons (2022–2025) has been above that 2016–2025 average, so the burden has been elevated and geographically wider in recent years — though 2018 remains the peak. Figures are reported locally-acquired (autochthonous) human cases in EU/EEA Member States per ECDC. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and the set of reporting countries; West Nile virus activity is strongly driven by summer weather and varies sharply between seasons. ECDC is the primary surveillance authority for the complete European total." }, { "question": "How many West Nile virus cases were reported in Europe each year from 2016 to 2025?", "answer": "Locally-acquired human WNV cases in EU/EEA Member States by year — 2016: 225, 2017: 201, 2018: 1,548, 2019: 425, 2020: 316, 2021: 141, 2022: 1,113, 2023: 709, 2024: 1,171, 2025: 1,043. The peak was 2018 (1,548) and the lowest year was 2021 (141). For 2024 and 2025 ECDC's wider \"Europe\" headline (including EU-neighbouring countries) was higher (1,436 and 1,112). Source: ECDC; year-to-year comparisons are affected by changes in surveillance and case definitions." }, { "question": "How many West Nile virus cases were there in Europe in the last five years?", "answer": "Locally-acquired human WNV cases in EU/EEA Member States, last five seasons — 2021: 141, 2022: 1,113, 2023: 709, 2024: 1,171, 2025: 1,043. ECDC is the primary source for the complete European total." }, { "question": "What was the worst year for West Nile virus in Europe?", "answer": "2018 was the worst recorded European West Nile virus season, with 1,548 locally-acquired human cases in EU/EEA Member States — which ECDC attributed to an exceptionally warm summer. The lowest recent year was 2021 (141). Year-to-year comparisons are affected by changes in surveillance and case definitions." } ] }, { "disease": "Chikungunya", "disease_code": "CHIKV", "region_scope": "EU/EEA", "metric": "Locally-acquired (autochthonous) human cases", "unit": "cases", "temporal_coverage": "2007-01-01/2025-12-31", "source_authority": "European Centre for Disease Prevention and Control (ECDC)", "caveat": "Figures are reported locally-acquired (autochthonous) human chikungunya cases in EU/EEA Member States (mainland) per ECDC. Chikungunya transmission in Europe is episodic: self-limiting Aedes albopictus clusters that open and close rather than a continuous yearly burden, so most years since 2007 have had zero autochthonous EU/EEA cases and the series is intentionally gappy. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and vector spread, and any single warm season can produce an outsized cluster. Counts here exclude travel-imported cases and exclude EU outermost regions (e.g. Réunion and Mayotte), which ECDC reports separately and where 2025 case numbers were far larger. ECDC is the primary surveillance authority for the complete European total.", "point_count": 6, "points": [ { "year": 2007, "eu_eea_cases": 330, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/infectious-disease-topics/chikungunya-virus-disease/surveillance-and-updates/local-transmission-previous-years", "source_authority": "ECDC · Historical data on local transmission of chikungunya virus disease in the EU/EEA", "last_updated": "2026-06-15", "notes": "First-ever autochthonous chikungunya outbreak in continental Europe: Italy, Emilia-Romagna (Ravenna province), vector Aedes albopictus, seeded by a traveller from India. ECDC's historical local-transmission table records the event as 330 suspected, probable and confirmed cases (confirmed-only counts in the literature are ≈205–247); ECDC's published table figure is used here for cross-year source consistency. Deaths not reported by ECDC (null, not zero)." }, { "year": 2010, "eu_eea_cases": 2, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/infectious-disease-topics/chikungunya-virus-disease/surveillance-and-updates/local-transmission-previous-years", "source_authority": "ECDC · Historical data on local transmission of chikungunya virus disease in the EU/EEA", "last_updated": "2026-06-15", "notes": "France only — two laboratory-confirmed autochthonous cases in Fréjus (Var), September, linked to an imported case (origin India), vector Aedes albopictus." }, { "year": 2014, "eu_eea_cases": 12, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/infectious-disease-topics/chikungunya-virus-disease/surveillance-and-updates/local-transmission-previous-years", "source_authority": "ECDC · Historical data on local transmission of chikungunya virus disease in the EU/EEA", "last_updated": "2026-06-15", "notes": "France only — 12 autochthonous cases (11 confirmed + 1 probable) in a district of Montpellier (Hérault), September–October; primary case imported from Cameroon, vector Aedes albopictus." }, { "year": 2017, "eu_eea_cases": 303, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/chikungunya-virus-disease-annual-epidemiological-report-2017.pdf", "source_authority": "ECDC · Annual Epidemiological Report for 2017 — Chikungunya virus disease", "last_updated": "2026-06-15", "notes": "Two unrelated clusters in one season — France (Var: Le Cannet-des-Maures/Taradeau) and Italy (Lazio: Anzio/Rome + Calabria). 303 is ECDC's EU/EEA locally-acquired surveillance headline in the 2017 Annual Epidemiological Report ('303 cases (55.3%) were locally acquired'), the same construct the WNV series trends year over year. Higher outbreak-investigation counts (≈499, summing confirmed+probable across the two events) are not metric-consistent and are not used." }, { "year": 2024, "eu_eea_cases": 1, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/Communicable-disease-threats-report-week-47-2024.pdf", "source_authority": "ECDC · Communicable Disease Threats Report, week 47 2024", "last_updated": "2026-06-15", "notes": "France only — a single autochthonous case in the Île-de-France (Paris area), July: the first mainland EU/EEA autochthonous chikungunya since the 2017 clusters and the most northerly on record. Excludes the Réunion (French outermost region) cases and the global caseload reported in the same ECDC update." }, { "year": 2025, "eu_eea_cases": 1172, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": true, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/Communicable-disease-threats-report-week-49-2025.pdf", "source_authority": "ECDC · Communicable Disease Threats Report, week 49 2025 (final end-of-season, data to 3 December 2025)", "last_updated": "2026-06-15", "notes": "By far the largest mainland EU/EEA autochthonous chikungunya season on record: France 788 cases across 78 clusters + Italy 384 across six clusters = 1,172 — a Mosticare subtotal of ECDC's two per-country totals (hence eu_eea_is_subtotal). Final end-of-season figure (eight French cases removed after epidemiological review; ECDC concluded its 2025 weekly reporting). Excludes the large Réunion outbreak (a French outermost region, the import source). Deaths among mainland EU/EEA autochthonous cases not reported by ECDC (null, not zero)." } ], "summary": { "first_year": 2007, "last_year": 2025, "count": 6, "mean_cases": 303, "peak": { "year": 2025, "cases": 1172 }, "trough": { "year": 2024, "cases": 1 }, "latest": { "year": 2025, "cases": 1172 }, "recent_above_mean_years": [ 2025 ], "answer": "Autochthonous (locally-acquired) chikungunya in the EU/EEA is episodic, not a steady year-on-year trend: occasional, self-limiting summer clusters spread by the Aedes albopictus tiger mosquito, with most years since the first European outbreak in 2007 reporting no local cases at all. EU/EEA Member States have recorded autochthonous chikungunya in only 6 years between 2007 and 2025 — 2007 (330), 2010 (2), 2014 (12), 2017 (303), 2024 (1) and 2025 (1,172) cases — with 2025 by far the largest on record (1,172). The two most recent seasons (2024: 1, then 2025: 1,172) show local transmission reaching larger clusters and further north — best read as rising risk of episodic outbreaks rather than a clean upward trend. Figures are reported locally-acquired (autochthonous) human chikungunya cases in EU/EEA Member States (mainland) per ECDC. Chikungunya transmission in Europe is episodic: self-limiting Aedes albopictus clusters that open and close rather than a continuous yearly burden, so most years since 2007 have had zero autochthonous EU/EEA cases and the series is intentionally gappy. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and vector spread, and any single warm season can produce an outsized cluster. Counts here exclude travel-imported cases and exclude EU outermost regions (e.g. Réunion and Mayotte), which ECDC reports separately and where 2025 case numbers were far larger. ECDC is the primary surveillance authority for the complete European total." }, "questions": [ { "question": "Is chikungunya increasing in Europe?", "answer": "Autochthonous (locally-acquired) chikungunya in the EU/EEA is episodic, not a steady year-on-year trend: occasional, self-limiting summer clusters spread by the Aedes albopictus tiger mosquito, with most years since the first European outbreak in 2007 reporting no local cases at all. EU/EEA Member States have recorded autochthonous chikungunya in only 6 years between 2007 and 2025 — 2007 (330), 2010 (2), 2014 (12), 2017 (303), 2024 (1) and 2025 (1,172) cases — with 2025 by far the largest on record (1,172). The two most recent seasons (2024: 1, then 2025: 1,172) show local transmission reaching larger clusters and further north — best read as rising risk of episodic outbreaks rather than a clean upward trend. Figures are reported locally-acquired (autochthonous) human chikungunya cases in EU/EEA Member States (mainland) per ECDC. Chikungunya transmission in Europe is episodic: self-limiting Aedes albopictus clusters that open and close rather than a continuous yearly burden, so most years since 2007 have had zero autochthonous EU/EEA cases and the series is intentionally gappy. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions and vector spread, and any single warm season can produce an outsized cluster. Counts here exclude travel-imported cases and exclude EU outermost regions (e.g. Réunion and Mayotte), which ECDC reports separately and where 2025 case numbers were far larger. ECDC is the primary surveillance authority for the complete European total." }, { "question": "In which years has Europe had locally-acquired chikungunya, and how many cases?", "answer": "Autochthonous chikungunya has been reported in EU/EEA Member States in 6 years between 2007 and 2025 — 2007 (330), 2010 (2), 2014 (12), 2017 (303), 2024 (1) and 2025 (1,172) cases — with no local transmission in the intervening years. The largest season was 2025 (1,172). Source: ECDC; counts are mainland EU/EEA and exclude travel-imported cases and EU outermost regions such as Réunion." }, { "question": "What was the biggest chikungunya outbreak year in Europe?", "answer": "2025, with 1,172 locally-acquired chikungunya cases across EU/EEA Member States — by far the largest European season on record and an order of magnitude above any earlier year. Source: ECDC; the figure excludes EU outermost regions, which ECDC reports separately." } ] }, { "disease": "Dengue", "disease_code": "DENV", "region_scope": "EU/EEA", "metric": "Locally-acquired (autochthonous) human cases", "unit": "cases", "temporal_coverage": "2010-01-01/2025-12-31", "source_authority": "European Centre for Disease Prevention and Control (ECDC)", "caveat": "Figures are reported locally-acquired (autochthonous) human dengue cases in EU/EEA Member States (mainland; EU outermost regions such as Madeira are excluded, as ECDC reports them separately) per ECDC's historical local-transmission data. They exclude the far larger travel-imported caseload. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions, the establishment of the Aedes albopictus mosquito and the set of reporting countries; autochthonous dengue is strongly driven by summer weather and imported seeding, so it varies sharply between seasons. The 2025 figure is a provisional end-of-season count from ECDC's weekly Communicable Disease Threats Report, not a finalised Annual Epidemiological Report, and may be revised. ECDC is the primary surveillance authority.", "point_count": 12, "points": [ { "year": 2010, "eu_eea_cases": 12, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "First-ever autochthonous dengue in mainland EU/EEA: Croatia 10 (Korčula Island / Pelješac) + France 2 (Alpes-Maritimes)." }, { "year": 2013, "eu_eea_cases": 1, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 1 (Bouches-du-Rhône). 2011 and 2012 had no mainland autochthonous transmission (the 2012 Madeira outbreak is an EU outermost region, excluded from this mainland series)." }, { "year": 2014, "eu_eea_cases": 4, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 4 (Var, Bouches-du-Rhône)." }, { "year": 2015, "eu_eea_cases": 8, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 8 (Gard — the Nîmes cluster)." }, { "year": 2018, "eu_eea_cases": 14, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 8 + Spain 6 (Spain's first autochthonous dengue) = 14. 2016 and 2017 had no mainland autochthonous transmission." }, { "year": 2019, "eu_eea_cases": 10, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 9 + Spain 1 = 10 vector-borne autochthonous cases (latest revised ECDC table). The 2019 Annual Epidemiological Report's headline of 12 additionally counted one sexual-transmission and one laboratory case, which are not vector-borne and are excluded for metric consistency." }, { "year": 2020, "eu_eea_cases": 23, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 13 + Italy 10 (Italy's first autochthonous dengue, Veneto) = 23. Latest revised ECDC figure; the original 2020 AER stated 24 (Italy later revised 11 → 10)." }, { "year": 2021, "eu_eea_cases": 2, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025)", "last_updated": "2026-06-15", "notes": "France 2 (Var, Hérault). Latest revised ECDC figure; the original 2021 AER stated 3." }, { "year": 2022, "eu_eea_cases": 71, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025); corroborated by ECDC news, 'increasing trend' release (Jun 2024)", "last_updated": "2026-06-15", "notes": "France 65 (seven departments) + Spain 6 (Ibiza) = 71. The sharp multi-year rise begins here; ECDC's own reporting cites 71 as the EU/EEA total for 2022." }, { "year": 2023, "eu_eea_cases": 130, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025); corroborated by ECDC news, 'increasing trend' release (Jun 2024)", "last_updated": "2026-06-15", "notes": "France 45 + Italy 82 (Lodi, Rome, Latina) + Spain 3 (Catalonia) = 130. ECDC reports 130 locally-acquired EU/EEA cases for 2023." }, { "year": 2024, "eu_eea_cases": 304, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": false, "source_url": "https://www.ecdc.europa.eu/en/all-topics-z/dengue/surveillance-and-disease-data/autochthonous-transmission-dengue-virus-eueea-previous-years", "source_authority": "ECDC · Historical data on local transmission of dengue in the EU/EEA (updated 9 March 2025); corroborated by ECDC news, 'increasing trend' release", "last_updated": "2026-06-15", "notes": "Record EU/EEA year: France 83 + Italy 213 (the Marches 146, Emilia-Romagna 36, Abruzzo 15, Lombardy 12, Tuscany 2, Veneto 1) + Spain 8 = 304. ECDC describes 304 as 'an increasing trend' versus 130 (2023) and 71 (2022); it exceeds the combined 2010–2023 total (275)." }, { "year": 2025, "eu_eea_cases": 33, "eu_eea_deaths": null, "all_europe_cases": null, "eu_eea_is_subtotal": true, "source_url": "https://www.ecdc.europa.eu/sites/default/files/documents/communicable-disease-threats-report-week-51-2025.pdf", "source_authority": "ECDC · Communicable Disease Threats Report, week 51 2025 (provisional, data to 19 November 2025)", "last_updated": "2026-06-15", "notes": "Provisional end-of-season figure (not yet finalised, not yet in ECDC's historical table): France 29 + Italy 4 = 33 — a Mosticare subtotal of ECDC's per-country figures (hence eu_eea_is_subtotal). Excludes Madeira (an EU outermost region). A much smaller season than the 2024 record; subject to revision when ECDC publishes its final 2025 figures." } ], "summary": { "first_year": 2010, "last_year": 2025, "count": 12, "mean_cases": 51, "peak": { "year": 2024, "cases": 304 }, "trough": { "year": 2013, "cases": 1 }, "latest": { "year": 2025, "cases": 33 }, "recent_above_mean_years": [], "answer": "Reported locally-acquired (autochthonous) dengue in the EU/EEA has risen sharply over the past decade rather than holding flat. EU/EEA Member States reported 71 (2022), 130 (2023) and 304 (2024) autochthonous human cases — 2024 the record, more than every earlier year in the 2010–2024 series combined (275). The most recent season (2025: 33) was smaller — these counts are import- and weather-driven and swing between years, but the multi-year direction has been upward. Figures are reported locally-acquired (autochthonous) human dengue cases in EU/EEA Member States (mainland; EU outermost regions such as Madeira are excluded, as ECDC reports them separately) per ECDC's historical local-transmission data. They exclude the far larger travel-imported caseload. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions, the establishment of the Aedes albopictus mosquito and the set of reporting countries; autochthonous dengue is strongly driven by summer weather and imported seeding, so it varies sharply between seasons. The 2025 figure is a provisional end-of-season count from ECDC's weekly Communicable Disease Threats Report, not a finalised Annual Epidemiological Report, and may be revised. ECDC is the primary surveillance authority." }, "questions": [ { "question": "Is dengue increasing in Europe?", "answer": "Reported locally-acquired (autochthonous) dengue in the EU/EEA has risen sharply over the past decade rather than holding flat. EU/EEA Member States reported 71 (2022), 130 (2023) and 304 (2024) autochthonous human cases — 2024 the record, more than every earlier year in the 2010–2024 series combined (275). The most recent season (2025: 33) was smaller — these counts are import- and weather-driven and swing between years, but the multi-year direction has been upward. Figures are reported locally-acquired (autochthonous) human dengue cases in EU/EEA Member States (mainland; EU outermost regions such as Madeira are excluded, as ECDC reports them separately) per ECDC's historical local-transmission data. They exclude the far larger travel-imported caseload. Year-to-year comparisons are affected by changes in surveillance intensity, case definitions, the establishment of the Aedes albopictus mosquito and the set of reporting countries; autochthonous dengue is strongly driven by summer weather and imported seeding, so it varies sharply between seasons. The 2025 figure is a provisional end-of-season count from ECDC's weekly Communicable Disease Threats Report, not a finalised Annual Epidemiological Report, and may be revised. ECDC is the primary surveillance authority." }, { "question": "How many locally-acquired dengue cases were reported in the EU each year from 2010 to 2025?", "answer": "Autochthonous human dengue cases in mainland EU/EEA Member States by year — 2010: 12, 2013: 1, 2014: 4, 2015: 8, 2018: 14, 2019: 10, 2020: 23, 2021: 2, 2022: 71, 2023: 130, 2024: 304, 2025: 33. The record was 2024 (304); years with no mainland autochthonous transmission are omitted. Source: ECDC; figures exclude travel-imported cases and EU outermost regions such as Madeira, and the most recent year is provisional." }, { "question": "What was the worst year for autochthonous dengue in Europe?", "answer": "2024, with 304 locally-acquired dengue cases across mainland EU/EEA Member States — a record ECDC described as an increasing trend versus earlier years. Source: ECDC." } ] } ] }