Ebola in Congo, over five thousand cases and 47.4% case fatality rate: sixth province reached

The Ebola virus disease outbreak of the Bundibugyo species in Congo (Kinshasa) continues to grow. External situation report number 14 from the WHO Regional Office for Africa, with data as of August 16, 2026, reports 640 additional confirmed cases and 367 additional confirmed deaths compared to the previous report. In the same document, the crude case fatality rate rises from 45.9% to 47.4%.

The virus has reached a sixth province with the confirmation of a case in Bas-Uélé, in the northeast of the country.

The overall picture is defined by the World Health Organization’s Disease Outbreak News, which as of August 12 indicates 4,665 confirmed cases and 2,184 deaths, with a case fatality rate of 46.8%. WHO describes this as the largest Ebola outbreak ever documented in the country: the comparison is with the 3,317 cases of the 2018-2020 outbreak.

The pace, not just the total. The ECDC update of August 19 records 187 new confirmed cases and 98 deaths compared to the previous day’s report, and counts 56 affected health zones out of 151 across six provinces. Nearly two hundred confirmed cases in twenty-four hours, in a context where registration takes place through health facilities scattered across a vast territory, indicates that the curve has not yet reversed direction.

The European center rates the probability of infection for residents of the European Union and the European Economic Area as very low. The U.S. Centers for Disease Control and Prevention, in an August 19 update, report that no case linked to this outbreak has been confirmed in the United States.

There is one countertrend figure: on July 28, 2026, Uganda’s Ministry of Health declared the outbreak in its own country over, with 20 confirmed cases and two deaths. The difference between Uganda’s twenty cases and Congo’s five thousand indicates that containment is possible, but nothing in the material available allows this to be attributed to a single measure.

The vaccine issue. The technical complication of this outbreak lies in the species of the virus: existing anti-Ebola treatments had been certified for a different species, Ebola Zaire virus. The report of the third meeting of the WHO Technical Advisory Group on vaccine candidate prioritization — dated July 31, 2026 and published on August 7 — indicates that the licensed vaccine Ervebo could be used in the response to the Congolese outbreak. This is reported by Healio based on the meeting minutes.

The indication rests on a study published in the New England Journal of Medicine that found possible cross-protection of Ervebo against the Bundibugyo species. The limitations must be stated precisely, because they change the meaning of the result: this is a laboratory study on serum samples from a previous cohort, not a clinical trial conducted on the current outbreak; it measures an immune response observed in a test tube, not protective efficacy verified in the field; the wording of the WHO advisors is conditional, and speaks of possibility, not demonstration. The number of samples analyzed and any declared conflicts of interest do not appear in the sources available to the editorial staff.

On the regulatory front, the European Medicines Agency is working with the African Medicines Agency and national African authorities on the design of clinical trials for medical countermeasures against the Bundibugyo virus. This is the missing piece: until clinical trials designed for this species exist, any efficacy assessment remains a laboratory hypothesis.

The next useful data point is WHO AFRO’s weekly report number 15: it will show whether the 640 confirmed cases in one week were a peak or a cruising speed.