The Bundibugyo virus disease outbreak in the Democratic Republic of the Congo continues to expand, reaching 8,442 confirmed cases and 4,080 deaths, with international medical evacuations to the Netherlands and Germany underscoring the risk of cross-border spread. In Europe, autochthonous chikungunya transmission in France has increased to 124 cases across 19 clusters, while Germany has reported its first confirmed symptomatic autochthonous human Sindbis virus infection in Baden-Württemberg. West Nile virus transmission remains widespread across 16 European countries, with 1,765 locally acquired cases reported this season, predominantly in Italy and Greece. In Asia, Thailand is experiencing an elevated leptospirosis season amid flooding, recording 3,303 cases and 46 deaths. Elsewhere, a possible fatal laboratory-acquired pneumonic plague case in the Russian Federation has prompted the hospitalisation of 197 contacts, and Zambia has declared a cholera outbreak involving 304 suspected cases.
Chikungunya, France
Local chikungunya transmission continues to increase in France, with 34 new locally acquired cases reported during the latest week, bringing the 2026 total to 124 cases as of 30 September. Notably, 18 of the new cases occurred in Prayssac (Lot department). Cases are now distributed across 19 clusters, including six newly identified clusters, with 17 clusters currently active. The largest active cluster is located in Prignac-et-Marcamps (Gironde department) and comprises 30 cases, highlighting continued and geographically dispersed autochthonous chikungunya transmission in mainland France.
Sindbis virus disease, Germany
On 1 October 2026, the Robert Koch Institute reported the first confirmed symptomatic autochthonous human Sindbis virus infection in Germany, located in Baden-Württemberg. Previously, evidence of the virus circulating in the country was limited to detections in mosquitoes and wild birds, as well as specific IgG antibodies found in four out of 3,389 (0.1%) healthy blood donors. Sindbis virus is transmitted primarily through mosquito bites, with birds serving as the main reservoir and humans as incidental hosts. Sindbis virus infection is generally mild and self-limiting, although persistent arthralgia or arthritis may occur; fatal infections have not been reported. No specific antiviral treatment or vaccine is available.
West Nile virus disease, Europe and United States
West Nile virus activity remains substantial across Europe and parts of the US. In Europe, 1,765 locally acquired human cases have been reported across 16 countries during the 2026 transmission season as of 30 September, with Italy (721), Greece (420), Spain (131), France (128) and Romania (117) reporting the highest numbers; 202 areas have reported local transmission, including 16 newly affected areas in the latest reporting week. In the US, Los Angeles County, California, is experiencing a marked increase, with 135 human infections and five deaths reported since the beginning of this year.
Leptospirosis, Thailand
Thailand is experiencing an elevated leptospirosis season amid ongoing flooding, with 3303 cases and 46 deaths reported. Nationwide case counts have tracked above the five-year weekly median since early July 2026. Multi-regional transmission is currently spanning the southern, northern, and northeastern provinces.
Ebola disease outbreak caused by Bundibugyo virus, Democratic Republic of the Congo
The Bundibugyo virus disease outbreak continues to expand in the Democratic Republic of the Congo (DRC), with 8,442 confirmed cases and 4,080 deaths (CFR 48%) reported as of 2 October 2026; a further 405 suspected cases are under investigation. At least 2,213 patients have recovered in the DRC. Notably, the DRC case count includes one patient currently receiving treatment in the Netherlands and two patients who received treatment in Germany, illustrating the potential for international medical evacuation of cases. The outbreak remains of major concern given the sustained transmission, high case fatality and continued risk of geographic and cross-border spread.
Since Sept. 30, France reported 34 new locally acquired chikungunya virus disease cases, including 18 in the municipality of Prayssac (Lot department), bringing the total to 124 cases
103 confirmed cases of DENV-1 and six hospitalisations reported across Majuro and Ebeye.
59,543 cumulative cases and 70 deaths reported in 2026 amid El Niño conditions
Province-wide outbreak declared following 674 cases and a surge since August.
28 new cases in week 37, with DENV-1 and DENV-2 predominant; blue alert active.
62 new autochthonous cases reported, bringing the 2026 total to 252, mostly DENV-2.
Two family clusters with eight cases and two deaths under investigation in Souss-Massa.
35 deaths and over 200,000 dog bites reported across the province in nine months.
14 confirmed cases, including two deaths, reported across eight health districts this year.
Possible fatal laboratory-acquired pneumonic plague case reported; 197 contacts hospitalized for observation.
First confirmed symptomatic autochthonous human infection reported in Baden-Württemberg by the RKI.
Four confirmed cases, including one child, reported in Agidel after a year of inactivity.
1,765 locally acquired human cases reported in 16 countries during the 2026 transmission season as of 30 September
135 cases and five deaths reported in Los Angeles County, exceeding the five-year average.
12 cases diagnosed in Salta province in 2026, exceeding annual totals for 2020–2025.
3303 cases and 46 deaths reported across multiple regions amid ongoing flooding.
16,597 cases reported in 2024–25, with recent kit-positive cases and nine deaths in Salyan.
First documented cases and confirmed active local circulation in Aden and the Arabian Peninsula.
Outbreak declared with 304 suspected cases and 11 deaths across five provinces.
One additional confirmed case in the Dakar region brings the annual total to eight.
On October 2, 2026, the Democratic Republic of the Congo (DRC) reported a total of 8 442 confirmed cases, including 4 080 related deaths
The ESCMID-AUMC Epi Alert, a strategic collaboration between the ESCMID Emerging Infections Subcommittee and the Center of Tropical Medicine and Travel Medicine of Amsterdam University Medical Center (AUMC) that integrates expertise and resources to advance emerging infectious diseases surveillance and intelligence sharing. This collaboration integrates ESCMID's extensive international network and emerging infections expertise with AUMC's proven surveillance capabilities, led by Dr. Abraham Goorhuis and the AUMC team and other collaborators form European Institutions.
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