The Bundibugyo virus disease outbreak in the Democratic Republic of the Congo continues to expand, with 7,475 confirmed cases and 3,605 deaths reported across seven provinces, while a smaller outbreak in Uganda has been declared over. In Europe, West Nile virus transmission is expanding, with 1,482 locally acquired cases across 16 countries, led by Italy and Greece. Measles transmission persists globally, notably with outbreaks in the Americas, Africa, and Europe. Denmark has reported six hospitalised cases of severe iatrogenic botulism linked to cosmetic injections. In North America, a mumps outbreak involving student-athletes is under investigation at San Diego State University. Elsewhere, Thailand recorded three cases of severe fever with thrombocytopenia syndrome, and Germany reported a cluster of eight locally acquired malaria cases linked to Frankfurt Airport.
Measles, Global
Measles transmission remains substantial across multiple regions. In the Americas, 52,480 confirmed cases have been reported across 16 countries, including 33,490 in Guatemala, while Mexico has reported 12,939 cases and 20 deaths in 2026 as of 14 September. In Africa, widespread transmission continues, with more than 143,000 suspected cases and 1,392 deaths reported across 23 African Union Member States; Mozambique is also experiencing an outbreak with nearly 1,500 reported cases. In the EU/EEA, 2,339 cases were reported during August 2025–July 2026, with ongoing outbreaks in Bulgaria and Sweden; among cases with known age and vaccination status, 73% were unvaccinated. The continued occurrence of large outbreaks across geographically diverse settings underscores the importance of closing immunity gaps and maintaining high two-dose measles vaccination coverage.
Mumps, United States
A mumps outbreak has been reported at San Diego State University (SDSU), California, involving three confirmed and two probable cases among student-athletes. The clustering of cases within an athletic population raises concern for further transmission given the close-contact environments associated with university sports and shared facilities. Public health and university authorities are investigating the outbreak and implementing measures to identify potentially exposed individuals and limit further spread.
West Nile virus disease, Europe
West Nile virus (WNV) transmission continues to expand across Europe, with 1,482 locally acquired human cases reported in 16 countries during the 2026 transmission season as of 17 September. Italy has reported the highest number of cases (652), followed by Greece (355), Spain (114), Romania (91), France (81) and North Macedonia (66). Overall, 180 areas have reported local WNV transmission, including 19 areas reported as affected for the first time during the latest reporting week. The continued geographic expansion of WNV activity underscores the importance of ongoing surveillance and measures to safeguard blood, blood components and other substances of human origin.
Wound botulism, Denmark
Six cases of severe iatrogenic botulism have been reported in Denmark following botulinum toxin injections for cosmetic purposes or treatment of hyperhidrosis; all six patients have been hospitalised. An unapproved botulinum toxin product administered at an unregistered clinic or by an unauthorised provider is suspected, although the source has not yet been confirmed.
Severe fever with thrombocytopenia syndrome, Thailand
In 2026, three cases of severe fever with thrombocytopenia syndrome (SFTS), including two fatalities, were recorded in Thailand. The disease has now been made notifiable. Previously, two fatal human cases of SFTS were reported in Phetchabun Province in October 2025.
Ebola virus disease, Democratic Republic of the Congo
The Bundibugyo Ebola outbreak continues to cause substantial transmission in the Democratic Republic of the Congo, with 7,475 confirmed cases and 3,605 deaths (CFR 48.2%) reported as of 16 September 2026. In the latest 24 hours, 71 new cases and 28 deaths were reported, with new cases concentrated in Ituri (41) and North Kivu (27). Ituri remains the epicentre, accounting for 5,792 cases (77.5% of all confirmed cases) and 2,642 deaths. While 62 health zones across seven provinces have been affected since the start of the outbreak, 54 health zones in five provinces are currently affected; 87.6% of identified contacts were reported as followed up.
Outbreak surpasses 19,500 cases and 47 deaths, including a nosocomial cluster in Veracruz.
Outbreak in Nampula province involves 1,498 cases and three deaths across 10 districts.
2,777 confirmed cases across 47 jurisdictions in 2026, with four deaths reported in Pennsylvania.
In July 2026, 29 EU/EEA countries reported measles data. Updates are provided for several countries and regions outside the EU/EEA.
290 cases with an 8.3% case fatality rate reported from January to April 2026.
1,183 probable and 58 confirmed cases reported, mostly in Tolima; CDC issues travel notice.
Cluster of eight locally acquired cases and two deaths linked to Frankfurt Airport.
Intense 2026 season exceeds 10-year average, with six regions reporting first-ever autochthonous human infections.
First locally acquired case since 2024 and one imported case confirmed in Chișinău.
Six severe iatrogenic botulism cases reported following cosmetic or excessive sweating treatments.
First recorded fatal case in a 34-year-old male linked to a workplace artificial lake.
Early epidemic warning issued as A(H1N1)pdm09 activity and hospitalizations rise ahead of vaccination rollout.
150 cerebral cases and four child deaths in East Singhbhum; Mumbai reports long-term increase.
Over 100 cases and four deaths in Salyan, alongside 282 cases in Baglung.
Three cases including two fatalities recorded in 2026; disease is now notifiable.
2,683 cases and 77 deaths across 11 districts, with 438 in Minawao refugee camp.
867 cumulative cases and 42 deaths reported, with geographic spread to new districts.
Over 30 suspected cases and four deaths reported across five affected health zones.
Multi-province cluster with an international travel link and epicenter in the Western Cape.
National emergency declared following 2003 new diagnoses and 59 infant infections in 2025.
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.
The Epi Alert aims to be a weekly publication. The briefings are curated by infectious disease specialists prioritising data from trusted sources (such as Beacon, H-Radar, Outbreaknews, WHO, ECDC, CDC) based on potential impact, geographic region and urgency/relevancy to clinical practice. It aims to provide concise summaries for busy healthcare professionals with direct links for further investigation and transparency.
This integrated collaboration represents a significant milestone in ESCMID's commitment to emerging infections preparedness, strengthening our collective capacity to detect, analyse, and respond to infectious disease threats through international cooperation.
Disclaimer: The information in this epi-alert is a weekly summary of the information that is available on the internet, mainly the websites of Beacon, H-Radar, Outbreaknews, WHO, ECDC, CDC, and others. For this summary, we consider issues that are most relevant to the ESCMID members involved in clinical patient care. Therefore, this report is not comprehensive, but we strive to include all major global issues in this report on a weekly basis.