WHO warns Congo Ebola outbreak may be far larger than reported

Four out of five new Ebola cases in parts of the Democratic Republic of the Congo have no known link to existing patients. On July 10, a World Health Organization official warned the outbreak was likely spreading far beyond official counts.

The outbreak was confirmed in May in the Democratic Republic of the Congo and Uganda and involves Bundibugyo virus disease, a strain with no approved vaccine or specific treatment. This is Congo’s 17th Ebola outbreak since the virus was first identified in 1976, and WHO classified the event as a public health emergency of international concern on May 17. The virus is moving through a remote, densely populated and insecure area with heavy population and trade movement, conditions that make case-finding harder and contact tracing more fragile.

WHO said on July 1 that Congo had reported 1,460 confirmed cases and 452 deaths. By July 8-9, Congo had 1,792 confirmed cases and 625 deaths, a jump WHO partly linked to expanded surveillance, testing and diagnostic capacity. Dr. Anne Ancia, WHO’s representative in Congo, said the outbreak’s “true scale has not yet been fully established.”

Roughly 70 percent of the first 400 deaths occurred outside health facilities, meaning many patients died before they could be isolated, tested or given supportive care. Health authorities have also been training 21,000 workers for house-to-house surveillance.

Uganda had reported 20 confirmed cases and two deaths as of July 2, and France notified WHO of a laboratory-confirmed Ebola case in a doctor who had returned from Congo on June 24. WHO and partner agencies are prioritizing surveillance, contact tracing, clinical preparedness, delivery of supplies, community engagement and cross-border preparedness.