Ebola spreading at unprecedented speed in Congo, top virologist warns

The Ebola outbreak in eastern Democratic Republic of Congo is spreading at a speed never before observed in the country, according to renowned Congolese virologist Jean-Jacques Muyembe.

The outbreak, officially recognized by Congolese authorities on May 15, had caused 1,916 deaths among 4,209 confirmed cases as of Aug. 7, French daily Le Monde reported Tuesday.

The death toll is approaching that of the 2018 Ebola epidemic, which lasted 22 months and claimed 2,287 lives, making it the deadliest outbreak recorded to date in Congo.

Muyembe, who co-discovered the Ebola virus in 1976 and remains director of the National Institute for Biomedical Research in Kinshasa, said the virus was likely circulating as early as January but was not detected until April or May.

"This is an exceptional speed of spread, which we have never observed before," he told Le Monde.

He said the response had been "slow and ineffective," citing weaknesses in surveillance, coordination problems and the impact of armed conflict and mining activity in densely populated eastern regions.

Muyembe also said official figures could significantly underestimate the true scale of the outbreak because some patients remain at home and go undetected.

The outbreak has expanded from three health zones to 53 and from three provinces to five in a short period, he added.

The outbreak is caused by the Bundibugyo strain, for which no approved vaccine or treatment is currently available. Clinical trials testing antibody and antiviral approaches are underway in Bunia and Mongbwalu.

World Health Organization (WHO) experts on Friday recommended prioritizing the licensed Ebola vaccine Ervebo for evaluation in a randomized clinical trial amid the outbreak.

The WHO said its Technical Advisory Group on candidate vaccine prioritization made the recommendation after reviewing new preliminary data showing that Ervebo offered "some level of cross-protection" against Bundibugyo virus disease in animal studies, particularly against death.

Ervebo is the only licensed Ebola vaccine, but it is approved against Ebola virus disease caused by the Zaire ebolavirus rather than the Bundibugyo virus.