By Deborah Cheloti and Kennedy Gakuha

The majority of new Ebola infections in eastern Democratic Republic of Congo (DRC) are emerging from previously unknown chains of transmission, exposing major gaps in contact tracing as community mistrust, insecurity and funding shortages undermine efforts to contain the outbreak, according to the World Health Organization (WHO).

Following an emergency assessment mission to Bunia, one of the hardest-hit cities in Ituri Province, WHO Emergencies Director Dr. Chikwe Ihekweazu warned that the outbreak has spread beyond the reach of conventional containment measures, making it increasingly difficult for health authorities to interrupt transmission.

"Perhaps the most alarming finding is that many of the newly reported deaths are people who died in their communities without ever reaching a health facility and without receiving care," Ihekweazu said. "As of today, 80% of new cases are outside our contact lists and are coming to us from unknown chains of transmission."

The finding suggests the outbreak is substantially larger than surveillance data alone can capture, as health officials struggle to identify infected individuals before they spread the virus to others.

The outbreak is caused by the Bundibugyo strain of Ebola virus, a rare variant for which there is currently no licensed vaccine or approved antiviral treatment. Congolese authorities officially declared the outbreak on May 15, 2026, although investigators believe the virus had been circulating undetected for several weeks.

As of the latest figures, the outbreak has infected 2,011 people and claimed 754 lives across five provinces in the DRC. Uganda has reported 20 cases and two deaths linked to cross-border transmission.

The Africa Centres for Disease Control and Prevention has described it as the fastest-growing Ebola outbreak on the continent, raising concerns that response efforts are struggling to keep pace with the spread of the virus.

Misinformation fuels resistance

Health workers say misinformation and community mistrust have become as formidable as the virus itself.

In Mongbwalu, one of the outbreak's epicentres in northeastern Congo, many residents initially believed the unexplained illnesses were caused by malaria, typhoid or diarrhoeal diseases rather than Ebola.

"The community does not believe in this disease. Despite the deaths, people don't believe in it," said John Tumujimbe, who leads a team responsible for dignified and safe burials.

Tumujimbe said health workers only confirmed Ebola after laboratory testing by the Institut National de Recherche Biomédicale (INRB), the DRC's national biomedical research institute.

Even after laboratory confirmation, some residents remained unconvinced.

One resident, who requested anonymity, said rumours circulated that contaminated coffins were responsible for the deaths, while others falsely claimed the virus had been created in a laboratory or that vaccination posed a greater risk than the disease itself.

Public health officials warn such misinformation discourages people from seeking treatment, reporting symptoms and cooperating with contact tracing teams, allowing the virus to spread undetected.

Conflict and funding shortages strain the response

The outbreak is unfolding in one of the world's most challenging humanitarian settings.

Years of armed conflict, attacks on health facilities and deep mistrust of government authorities and international responders have complicated efforts to identify cases and safely isolate patients.

The response has been further weakened by funding shortages.

On July 13, dozens of healthcare workers at a primary Ebola treatment centre reportedly went on strike over months of unpaid salaries and hazard allowances, disrupting frontline services.

The deteriorating situation has also affected international responders. The U.S. Centers for Disease Control and Prevention confirmed that an American aid worker in eastern Congo tested positive for Ebola on July 11.

Capacity expands, but cases remain hidden

Despite the difficult operating environment, health authorities have significantly expanded response capacity.

Treatment capacity in Bunia has increased to nearly 800 beds, while laboratory testing has expanded from a single facility to 14 operational laboratories across affected areas.

Yet officials acknowledge those gains are being undermined because most infections are occurring outside known surveillance networks.

When four out of every five new patients are not previously identified as contacts, health experts say every confirmed case may represent a much larger, hidden chain of transmission.

Race for vaccines and treatments

Scientists are racing to develop vaccines and therapies against the Bundibugyo strain.

Clinical trials evaluating experimental treatments began last week in affected provinces.

Researchers at the University of Oxford and the Serum Institute of India are developing a vaccine using technology similar to that used during the COVID-19 pandemic, while Chinese scientists are testing a multivalent mRNA vaccine designed to protect against several Ebola strains, including Bundibugyo.

Health experts caution that even if new vaccines or treatments prove effective, they will have limited impact unless surveillance, contact tracing and community engagement improve.

Beyond the virus

Beyond its high mortality rate, Ebola leaves lasting psychological and social scars.

Survivors often experience trauma after witnessing multiple deaths, prolonged isolation and fear of infecting loved ones. Many also face stigma, discrimination and social rejection long after they recover.

For WHO and its partners, the latest findings underscore a sobering reality: scientific advances alone cannot end an Ebola outbreak. Without stronger surveillance, sustained funding and community trust, the virus will continue to spread through invisible chains of transmission that outpace even the most sophisticated emergency response.