That corresponds to roughly 1.16-times weekly growth in deaths, down from around 1.3-times seen earlier in the outbreak. The World Health Organization has described the epidemic, caused by the Bundibugyo strain of Ebola, as the fastest-growing on record and the second-largest ever, behind only the 2014-2016 West Africa outbreak that killed more than 11,000 people, according to UN News.
On 27 August, the DRC's health minister, Roger Kamba, launched a vaccination campaign for frontline workers in Kisangani using Merck's ERVEBO vaccine, targeting the affected provinces of Tshopo, Bas-Uele and Haut-Uele, according to the European Centre for Disease Prevention and Control. The WHO has approved 70,000 doses for use in Congo, with Euronews reports that "more than 50,000 doses have been received, and a further 20,000 will be used in a clinical trial to study whether the vaccine protects against the Bundibugyo virus." ERVEBO is licensed only against the Zaire strain of Ebola, and health authorities say it could offer some protection against Bundibugyo because the two strains are related, though whether it actually prevents illness in people infected with this variant remains under study. The doses are being administered under a compassionate-use programme, which permits a medical product to be used in a serious disease situation despite lacking specific approval for that purpose.
Alongside the ERVEBO rollout, work continues on a vaccine designed specifically for the Bundibugyo strain. The University of Oxford's Vaccine Group and Moderna have both started human trials, currently in Phase I to evaluate safety, tolerability and immune response. Moderna's candidate, mRNA-1469, uses the same messenger RNA platform behind the company's Covid-19 vaccines and has been authorised for study by Health Canada, while a WHO advisory group meeting on 31 July recommended prioritising Ervebo for a Phase 3 trial in the DRC, according to Healio. Katrina Pollock, the trial's chief investigator, called the decision "an important milestone for the trial and marks the next phase in our multinational collaborative journey to develop a Bundibugyo ebolavirus vaccine."
The outbreak, first declared on 15 May in Ituri Province, has since spread to five additional provinces: North Kivu, South Kivu, Haut-Uélé, Tshopo and Bas-Uélé, according to Wikipedia's tracking of the epidemic. Uganda's linked outbreak, by contrast, appears to have ended: the country's last confirmed case was discharged from Kampala's Mulago National Referral Isolation Centre on 16 July, and no new cases have been reported since 21 June. Poor healthcare infrastructure and ongoing armed conflict in eastern DRC continue to hamper detection, treatment and prevention efforts, and it is considered likely that the true scale of the outbreak exceeds the confirmed case counts.
Separately, H5N1 bird flu was detected in seven captive mink in Utah. Mink are considered a potential mixing vessel for human and avian flu strains, and a previous mink outbreak is thought to have produced a mutation that aided human-to-human transmission.