WHO says DRC Ebola outbreak two to four times larger than official figures as first antiviral trial begins

The real scale of the outbreak

Two months after the Democratic Republic of the Congo declared its 17th Ebola outbreak, the World Health Organization warned that official figures undercount the crisis by a factor of two to four. Congolese authorities reported 2,011 confirmed cases and 754 deaths as of 15 July, but the WHO's emergency director, Chikwe Ihekweazu, told reporters in Geneva that modeling suggests the true extent is far larger. "The outbreak is at least two to four times the number of cases detected," he said. The last official situation report, dated 12 July and published on 14 July, listed 1,963 cases and 719 deaths. The rapid revision upward by the next day points to a worsening trajectory.

This is now the third largest Ebola outbreak ever; we have seen the fastest growth in a single month since the start of the outbreak and among all those we have managed.

Transmission outrunning the response

The most alarming finding, Ihekweazu said after returning from the outbreak zone, is that 80% of newly reported cases are outside official contact lists: they come from unknown chains of transmission. Many of the dead never reached a health facility. People who die in their communities cannot be isolated, treated or have their contacts traced promptly, which increases the risk of further transmission. The outbreak was declared on 15 May in Ituri province, but experts believe the virus had been circulating since at least April. Cases have now been confirmed in five provinces of the DRC and in neighboring Uganda, though over 90% remain concentrated in Ituri.

As of today, 80% of new cases are outside our contact lists and so are coming to us from unknown chains of transmission.

The WHO noted that contact-tracing performance, while still below the 90% target needed to control the outbreak, has improved to 80% in recent weeks. Treatment capacity in Bunia has grown to nearly 800 beds, and laboratory capacity has expanded from one to 14 facilities.

First antiviral trial offers a possible turning point

On 14 July, the WHO announced the launch of EBO-PEP, the first clinical trial to evaluate a post-exposure prophylaxis using the oral antiviral obeldesivir in patients exposed to the Bundibugyo variant. The trial began recruiting its first participants on the same day in Bunia and aims to enroll close to 1,000 asymptomatic people who have been in contact with confirmed cases. The experimental drug, developed by the American pharmaceutical company Gilead Sciences, has shown preclinical efficacy against filoviruses. There is currently no approved vaccine or specific treatment for the Bundibugyo strain.

Every discovery begins with hope.

WHO Director-General Tedros Adhanom Ghebreyesus said that if the antiviral proves effective in high-risk individuals after exposure, it could represent significant progress in preventing disease development among contacts. Tedros is expected to visit the DRC, including the epicenter in Ituri, before the end of the week.

Health workers on the brink

The response has been further complicated by labor unrest. On 14 July, dozens of healthcare workers at an Ebola treatment center in northeast Congo went on strike over unpaid salaries and bonuses. They agreed to resume work the following day only on the condition that the government pays them within 72 hours. The workers warned that even one day of strike action had already caused damage, with patients unable to access the center.

We hold the government solely responsible for any loss of life if the site closes after this ultimatum.

A strained international response

Médecins Sans Frontières called on 15 July for an urgent reinforcement of the international medical response, arguing that the resources currently deployed remain insufficient given the pace of the outbreak. The organization noted that the epidemic, caused by the rare Bundibugyo variant, has become the third largest ever recorded in the DRC and the fastest-growing in just two months. A funding gap, attacks on health facilities, ongoing armed group violence in eastern Congo, and community mistrust have all hampered containment efforts. The WHO continues to describe a response that is improving but that has not yet caught up with the virus.