African health authorities are preparing to use a vaccine originally developed for the Zaire ebolavirus strain to combat the current Ebola outbreak in eastern Democratic Republic of Congo (DRC), which involves a different and rapidly spreading strain known as Bundibugyo.

Jean Kaseya, director general of the African Centres for Disease Control (Africa CDC), told reporters in a videoconference on Thursday, August 6th, 2026, that test cases indicate the vaccine has been effective in eliminating deaths, though not necessarily symptoms, among vaccinated individuals. He stated, "we saw zero deaths among people who are vaccinated."

The outbreak has intensified significantly, with cases now reported in 51 health zones compared to just nine in May. Authorities estimate approximately 4,000 cases have been confirmed, up from 3,973 as of the previous Tuesday.

Kaseya spoke from Brazzaville in the neighboring Republic of Congo after meeting with World Health Organization (WHO) Director-General Tedros Adhanom Ghebreyesus in Kinshasa. He relayed Tedros's call for joint studies by WHO and Africa CDC to investigate whether the virus is mutating or if other factors are contributing to the unprecedented severity and rapid spread of this Bundibugyo outbreak, which is spreading six to eight times faster than any previous Ebola outbreak on record.

During the most severe Ebola outbreak on record, caused by the Zaire strain in DRC between 2018 and 2020, one patient was identified for every 57 contacts at risk, with 20 cases recorded and only two deaths.

The Africa CDC and WHO also plan to conduct further research to understand the current outbreak's unusual characteristics.

Sources