Three experimental Ebola vaccines are advancing to human trials as international health authorities work to contain a growing outbreak in Central Africa. The World Health Organisation confirmed on Tuesday that candidate vaccines from Johnson & Johnson, Merck, and a Chinese state-owned biotech firm have received regulatory clearance for accelerated testing. The move follows the confirmation of 47 cases and 23 deaths in the Democratic Republic of Congo’s North Kivu province, where conflict has hampered containment efforts.
Dr. Michael Ryan, executive director of the WHO Health Emergencies Programme, described the situation as “precarious,” noting that the current outbreak has a case fatality rate of nearly 50 per cent. “We are in a race against time,” he said. “These vaccines represent our best hope for curbing transmission, but we must also address the security and logistical challenges on the ground.”
The Johnson & Johnson candidate, developed in partnership with the University of Oxford, uses a prime-boost regimen that requires two doses. Merck’s vaccine, Ervebo, was deployed during the 2014-2016 West Africa epidemic and has received WHO prequalification. The Chinese candidate, administered as a single dose, is being tested for the first time in an outbreak setting.
International coordination has been complicated by political instability. Armed groups in North Kivu have attacked health workers and disrupted vaccination campaigns. The WHO has called for a ceasefire to allow humanitarian access, but no agreement has been reached.
Manufacturing capacity remains a concern. Merck has committed to producing 12 million doses by mid-2026, but current stockpiles are limited. Johnson & Johnson has pledged to accelerate production, while the Chinese manufacturer has offered doses at cost.
“The speed of these trials is unprecedented,” said Dr. Marie Ng, an epidemiologist at the London School of Hygiene and Tropical Medicine. “But we must ensure that regulatory shortcuts do not compromise safety.”
The outbreak is the second largest in the DRC since 2018, when a separate epidemic infected more than 3,000 people. Neighbouring countries, including Rwanda and Uganda, have heightened surveillance at border crossings.
The WHO has requested $45 million in emergency funding, of which only $15 million has been pledged. Without additional resources, the agency warns, the outbreak could spread beyond the region.
