DR Congo's Ebola outbreak becomes world's second-largest, with no approved vaccine

The numbers arrived on a Friday in late July, and they told a story of an epidemic spiraling beyond anything the Democratic Republic of Congo had weathered before. Health officials confirmed 3,532 cases of Ebola across five provinces, with 1,556 deaths. The outbreak had crossed a threshold: it was now larger than the country's previous deadliest epidemic, the one that killed nearly 2,300 people between 2018 and 2020. Only once in recorded history had Ebola spread more widely—during the 2014-to-2016 West African crisis, which claimed 28,616 lives across Guinea, Liberia, and Sierra Leone. This new outbreak had become the second-largest on record.

What made this moment particularly alarming was the speed. The virus was moving through the population faster than any Ebola strain had before. In the first three months alone, it killed five times more people than previous outbreaks had at the same stage. Carl Skau, acting executive director of the UN World Food Programme, put it plainly: this was the fastest-spreading Ebola epidemic the world had ever seen. "The world needs to pay much more attention," he said. The trajectory was unmistakable. On July 15, confirmed cases stood at 2,000. Within weeks, that number had nearly doubled.

The culprit was the Bundibugyo strain of Ebola, a variant that presented an immediate and sobering problem: there was no approved vaccine. There was no approved treatment. The medical arsenal that had been deployed against other Ebola outbreaks—the vaccines that had helped contain previous crises—did not exist for this strain. The virus spreads through direct contact with bodily fluids of infected people, and in a region already fractured by conflict and instability, containment became exponentially harder.

The outbreak was centered in Ituri province in northeastern DR Congo, near the borders with South Sudan and Uganda. But it had not stayed contained. Cases had spread to four other provinces, including North Kivu and South Kivu, where large swaths of territory were controlled by the M23 rebel group, a militia backed by Rwanda. The conflict that had plagued eastern Congo for years was now a complicating factor in one of the world's most dangerous epidemics. Health officials acknowledged they did not fully understand the true scale of what was happening. The virus was moving through a landscape of violence and displacement, where access to affected populations was difficult and trust in institutions was fractured.

Yet there were glimmers of hope in the research pipeline. The World Health Organization had identified a vaccine candidate developed by Hilleman Laboratories, a Singapore-based company, as the most promising option against the Bundibugyo strain. The University of Oxford was also developing a separate vaccine, and the first volunteer had received a dose in an ongoing clinical trial just days before the outbreak numbers were announced. These were early-stage efforts, experimental and unproven, but they represented the only realistic path toward a medical intervention.

The race was on. Every week that passed meant thousands more people in a region already struggling with poverty, displacement, and armed conflict were at risk. The outbreak had moved from a regional concern to a global one, a reminder that in an interconnected world, an epidemic in a remote corner of Africa was everyone's problem. The question now was whether experimental vaccines could be developed, tested, and deployed fast enough to slow a virus that had already proven itself to be the most relentless Ebola had ever been.