African leaders and health agencies are intensifying efforts to contain the growing Ebola outbreak in the Democratic Republic of Congo and Uganda, with nearly $500 million pledged for the response as vaccine developers race to produce treatments tailored to the current strain amid rising infections and deaths.

Speaking during a virtual high-level ministerial briefing on Monday, Jean Kaseya, director-general of the Africa Centres for Disease Control and Prevention, said more than 900 suspected cases had been reported in the DR Congo, with over 100 confirmed cases recorded in DR Congo and Uganda, alongside more than 200 confirmed deaths in both countries.

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He warned that the current outbreak had already surpassed the scale of previous Ebola outbreaks at the time it was officially declared.

"When the current outbreak was declared, we already had 236 suspected cases and 64 deaths, and despite the trend, we still don't have licensed vaccines or therapeutics," he said.

He cautioned against underestimating the threat, comparing the current situation to the early days of COVID-19.

"We are losing many people because Ebola has a case fatality rate of between 25 and 90 percent, compared to 1-2 percent for COVID-19," he said, adding that 11 countries were already at high risk of Ebola transmission.

Samuel Roger Kamba, the DR Congo's minister of public health, hygiene and social welfare, said authorities were monitoring more than 1,600 contacts as suspected cases continue to rise. "At least 145 to 147 people are hospitalized in isolation and receiving treatment," he said.

Kamba said sequencing of the virus showed the outbreak originated from animal transmission, exposing countries across the region to risk. He added that DR Congo was working closely with Uganda and Sudan to strengthen containment efforts.

Sania Nishtar, chief executive officer of Gavi, a global vaccine alliance, said vaccine developers are accelerating production of vaccine candidates for Bundibugyo, the strain that has caused the latest outbreaks in the DR Congo, in partnership with Coalition for Epidemic Preparedness Innovations.

"Several candidates are in early-stage development and could be advanced relatively quickly into clinical trials," she said.

Nishtar said three vaccine platforms are under development, although doses for clinical trials may not be available for six to nine months.

She added that the University of Oxford's ChAdOx Platform could enter clinical trials within two to three months, while mRNA candidates involving Moderna remain in early development.

She said Gavi currently maintains a stockpile of 500,000 doses of Ervebo, which has previously been used in outbreaks, including vaccination campaigns in the DR Congo's Ituri and North Kivu provinces, where the current outbreak is concentrated.

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Ayoade Alakija, Nigeria's ministerial global envoy on antimicrobial resistance to the Food and Agriculture Organization, urged African countries to urgently strengthen diagnostic capacity and containment measures.

"When monoclonal antibodies and vaccines are developed in nine months' time, if we do not contain this now, the world will lock its doors and will lock us all in Africa," she warned.

Cyril Ramaphosa, president of South Africa, said the outbreak needed to be rapidly contained because it was unfolding in areas marked by insecurity, porous borders and intense population movement.

"We call on all relevant partners and manufacturers to accelerate research and development, strengthen genomic surveillance, expand laboratory systems, and also fast-track the equitable delivery of safe and effective vaccines and therapeutics," he said.

Contact the writers at edithmutethya@chinadaily.com.cn