WHO Backs Clinical Trials for Two New Ebola Vaccines as Africa’s Outbreak Death Toll Surpasses 5,300.
The World Health Organisation (WHO) has recommended the inclusion of two new experimental Ebola vaccine candidates in ongoing clinical trials as health authorities intensify efforts to contain a deadly outbreak that has claimed more than 5,300 lives across Africa, with the Democratic Republic of Congo (DRC) bearing the greatest burden.
The announcement, made on Wednesday, November 4, 2026, represents a significant development in the international response to the outbreak, which is being driven by the Bundibugyo virus, a strain of Ebola for which no licensed vaccine currently exists.
The two vaccine candidates are ChAdOx1 BDBV, developed by the University of Oxford in partnership with the Serum Institute of India, and mRNA 1469, developed by American biotechnology company Moderna. Both were specifically designed to target the Bundibugyo virus.
According to WHO Director-General, Dr Tedros Adhanom Ghebreyesus, the organisation’s expert groups have recommended that the two candidates be added to the ongoing Tumaini clinical trial in the DRC. The country’s National Institute for Biomedical Research is leading the research in collaboration with WHO and other international health partners.
The development follows the commencement of an earlier vaccine trial involving Ervebo, an existing vaccine approved for protection against the more common Ebola virus. However, its effectiveness against the Bundibugyo strain has not been established, making further clinical evaluation necessary.
WHO explained that the Tumaini trial is designed to assess multiple vaccine candidates using a ring vaccination approach, which involves vaccinating people who have been in contact with confirmed Ebola patients. The strategy is intended to generate scientific evidence on the safety and effectiveness of the vaccines.
Data from the Africa Centres for Disease Control and Prevention (Africa CDC) indicate that the outbreak has resulted in more than 10,444 confirmed cases and over 5,300 deaths, with the majority recorded in the DRC. The reported fatality rate has exceeded 50 per cent, highlighting the severity of the public health emergency.
Dr Tedros welcomed the progress made by scientists and international partners but cautioned that vaccines alone would not bring the outbreak under control.
He emphasized the importance of early medical care, contact tracing, isolation of infected individuals, safe and dignified burial practices, and cooperation between health authorities and affected communities.
The WHO backed research also forms part of broader efforts to develop effective treatments for the Bundibugyo virus. Separate clinical investigations are examining potential treatments, including monoclonal antibodies and antiviral medicines, to improve survival rates among infected patients.
Results from the ongoing vaccine trial are expected in early 2027, according to WHO.
The latest development underscores the importance of sustained investment in African public health infrastructure, scientific research and international cooperation. As the continent continues to confront infectious disease emergencies, strengthening local research institutions and improving access to healthcare remain critical to preventing future outbreaks and protecting vulnerable populations.







