DRC launches Ebola vaccine trial for frontline workers

An Ebola vaccine trial is under way in the Democratic Republic of the Congo, involving frontline health workers and others involved in the response. The World Health Organization said that 20,000 doses of the Ervebo vaccine have been allocated for the research vaccination program in the epicenter of the outbreak — Ituri province.

The aim of the trial is to improve understanding of how effective the vaccine is against Ebola Bundibugyo virus and to protect individuals most exposed to it.

The Ervebo vaccine has been "highly effective" against Ebola Zaire virus in previous outbreaks, according to WHO, but it is not yet known whether it can provide meaningful protection against Ebola Bundibugyo disease, which continues to spread in the DRC.

A total of 70,000 doses of Ervebo have been made available to Congolese authorities to support the outbreak response and related research, according to WHO.

The research vaccination program, known as BRAVO, is being jointly launched by organizations including Médecins Sans Frontières — also known as Doctors Without Borders — DRC Ministry of Health, and Africa Centres for Disease Control and Prevention.

Launched on September 19 at a WHO-run training center for health workers in Bunia, the study will follow frontline workers over time to assess the effect of the Ervebo vaccine in the current outbreak.

"The study will run for nine to 12 months, including three months of vaccination and at least six months of follow-up," MSF said in a statement. "It will target 20,000 frontline workers in Ituri and North Kivu provinces, where health workers and other responders face a particularly high risk of exposure to the virus."

The vaccine has been widely used in the DRC and has an established safety profile. However, it was developed and licensed for Ebola virus disease caused by Zaire ebolavirus, rather than the Bundibugyo virus responsible for the current outbreak.

WHO said it is not known whether Ervebo provides meaningful protection against Bundibugyo virus in humans. Its current guidance recommends that the vaccine be used against the virus only within research protocols while evidence is generated.

Guyguy Manangama, an epidemiologist and deputy director of operations at MSF, said preliminary data suggested Ervebo could offer some degree of protection against Bundibugyo virus.

"Even partial protection could help reduce severe illness and deaths," Manangama said, adding that such potential benefits needed to be demonstrated scientifically.

The outbreak's epicenter remains Ituri province in eastern DRC, although the virus has spread to seven provinces since it was confirmed in May. The number of confirmed Ebola cases sits at 8,067, with 3,901 deaths, the DRC government said on Monday, marking the first time cases have surpassed 8,000 in the ongoing outbreak. The vaccination efforts are intensifying, with the official launch in Bunia of vaccination for frontline health workers.

The trial comes as health authorities confront a complex outbreak in an area already affected by prolonged insecurity and a humanitarian crisis. The eastern DRC has experienced decades of conflict and displacement, complicating access to affected communities and putting additional pressure on health services. The security situation has also created challenges for disease surveillance, contact tracing, and the movement of health workers and supplies.

Community mobilization is also continuing, particularly in Ituri, where more than 94,000 people have been reached through home visits, according to the DRC government. Psychosocial support for children affected by the epidemic is also being strengthened in several provinces.

WHO's Regional Office for Africa said on Tuesday that more than 2,800 traditional healers and private-sector health professionals in Ituri could help strengthen early detection and referral of suspected Ebola cases.

The agency said these workers are often among the first points of contact for communities and can help identify suspected cases, trigger alerts, and facilitate prompt referral to care.

WHO has stressed the importance of community involvement in controlling the outbreak.

"Community engagement will be key," WHO said. "It is only when communities are engaged in the response that such outbreaks are brought under control."

The outbreak has also raised particular concerns over the impact on children. WHO's Africa office said children account for nearly one-quarter of confirmed Ebola cases, but almost one-third of deaths. Among children under five, more than 60 percent of confirmed cases have proved fatal, compared with fewer than 30 percent among adults.

Health workers face additional challenges when treating young children, who require pediatric-sized equipment, medication, and specially trained staff. In Ituri, treatment centers have been redesigned to allow greater contact between health workers and children without personal protective equipment and to facilitate family visits, while Ebola survivors have also joined the response in high-risk areas.