Health officials are racing to contain a growing Ebola outbreak in the Democratic Republic of Congo and Uganda, as the World Health Organization warned that a vaccine designed for the rare Bundibugyo strain may still be six to nine months away.
The outbreak has reached 600 suspected cases and 139 suspected deaths, while laboratory testing has confirmed 51 infections in DR Congo and two in neighbouring Uganda. Both Ugandan cases involved people who had travelled from DR Congo, and one of them has died.
The WHO has declared the outbreak a public health emergency of international concern, although its emergency committee has not classified it as a pandemic-level threat. Dr Tedros Adhanom Ghebreyesus, the WHO’s director-general, said the risk remained concentrated in the affected countries and surrounding region.
“WHO assesses the risk of the epidemic as high at the national and regional levels and low at the global level,” he explained.
The confirmed Congolese cases have been reported in Ituri and North Kivu, two eastern provinces already strained by insecurity and fragile health services. The first known patient was a nurse in Bunia, Ituri’s provincial capital, who developed symptoms and died on 24 April.
Officials are still investigating how long the virus had been circulating before it was identified.
Tedros said the true scale of the outbreak in DR Congo was likely to be larger than confirmed figures suggest. “We know the scale of the epidemic in DRC is much larger,” he said, adding that deaths among healthcare workers were a particular concern.
Medical facilities in affected areas are under mounting pressure, with some centres reporting that they have little room left for suspected patients. Protective equipment has started to arrive, but local health workers say supplies remain inadequate.
The UK government has pledged up to £20 million to support containment efforts, including frontline staffing, infection control, and disease surveillance.
Bundibugyo poses a difficult challenge because there is no approved vaccine or specific treatment for the strain. DR Congo has faced repeated Ebola outbreaks, but most have involved the Zaire species, for which a vaccine exists. Bundibugyo has caused only two previously known outbreaks, in Uganda in 2007 and DR Congo in 2012.
WHO adviser Dr Vasee Moorthy said two possible vaccines are being studied, though neither has completed clinical trials for Bundibugyo. One candidate has been described as the most promising.
“This needs to be prioritised as the most promising Bundibugyo candidate vaccine,” he explained.
Moorthy said it was “likely to take six to nine months” before it could be ready.