DRC Ebola Outbreak Outpaced Four Earlier Outbreaks

An early-release report in Morbidity and Mortality Weekly Report found that the 2026 Ebola disease outbreak in the Democratic Republic of the Congo (DRC) grew faster in its first 100 days than four earlier outbreaks. From May 14 through August 21, 5,458 confirmed cases and 2,606 deaths (48% of confirmed cases) were reported across 57 of DRC’s 519 health zones.

The analysis compared the ongoing outbreak, caused by Bundibugyo virus, with the 2007 Uganda and 2012 DRC Bundibugyo virus outbreaks and the 2014 West Africa and 2018 DRC Ebola virus outbreaks. Those outbreaks represented the two largest prior Ebola outbreaks and the only two previous outbreaks caused by Bundibugyo virus.

When the outbreak was declared on May 15, the DRC Ministry of Health had identified 246 suspected cases and 76 suspected deaths, plus eight laboratory-confirmed cases and four deaths. The report identified 21 probable or confirmed related cases in Uganda and one travel-associated case in France; as of September 10, it found no evidence of community transmission outside DRC.

The 2026 outbreak had seven times as many cases at 100 days as the 2014 West Africa outbreak and 16 times as many as the 2018 DRC outbreak. Case definitions differed: the 2026 total included confirmed cases, the 2018 total included confirmed and probable cases, and the other outbreaks included confirmed, probable, and suspected cases. The authors also noted that multiple variables could affect the current outbreak’s future trajectory.

The report said delivery of aid was complicated by conflict involving armed groups, limited health care and other basic infrastructure, attacks on health workers, and community mistrust. The authors called for continued expansion of case and contact identification, diagnostic capacity, infection prevention and control, safe and dignified burials, cross-border surveillance and coordination, and community engagement.

Source: Rossow J, McHale TC, Fuller J, et al. Notes from the field: the first 100 days of five Ebola outbreaks—Democratic Republic of the Congo, Uganda, and West Africa, 2007–2026. MMWR Morb Mortal Wkly Rep. Published online September 15, 2026. doi:10.15585/mmwr.mm7537e1