Congo Ebola blind spots alarm health responders

Africa’s top disease control agency has warned that the true scale of the Ebola outbreak in the Democratic Republic of Congo cannot be established because response teams have not located thousands of people exposed to confirmed patients.

The Africa Centres for Disease Control and Prevention said contact tracing in Ituri, the outbreak’s epicentre, remains far below the level needed to break chains of transmission. Dr Jean Kaseya, the agency’s director general, said only a small fraction of likely contacts had been reached, leaving teams unable to judge how widely the Bundibugyo strain has spread through mining towns and displaced communities.

Health authorities had recorded 676 confirmed cases and 136 deaths by 12 June, with infections reported across Ituri, North Kivu and South Kivu. Uganda has also detected 19 cases linked to cross-border movement. The rise has placed the outbreak among Congo’s most serious Ebola flare-ups, with officials warning that reported numbers may lag behind transmission.

The outbreak was declared by Congo’s health ministry on 15 May after investigations into an illness with high mortality in Ituri. The first known suspected patient, a health worker, developed fever, haemorrhaging, vomiting and severe malaise in late April and died at a medical centre in Bunia. Confirmation of Bundibugyo virus disease followed laboratory testing, and the World Health Organization designated the situation a public health emergency of international concern on 17 May after cases were also confirmed in Uganda.

Contact tracing has become the response’s weakest link. Africa CDC has estimated that, in high-density settings such as Ituri’s mining towns, each confirmed patient may have had contact with about 40 people. That would put the pool of potential contacts far above the roughly 4,955 people listed by response teams, leaving many exposed people outside monitoring, testing and isolation systems.

The challenge is not only numerical. Eastern Congo’s outbreak zone is shaped by armed conflict, displacement, informal mining, poor roads and mistrust of emergency workers. Several health zones have reported very low tracing coverage, while some areas have been inaccessible because of insecurity. Attacks on burial teams, isolation units and treatment facilities have disrupted operations, raising the risk that families may hide symptoms or avoid clinics until patients are critically ill.

The virus has now reached Kpangba camp, a densely populated site in Ituri sheltering about 30,000 displaced people. Two deaths, a mother and daughter, were confirmed after death, heightening concern that transmission may have occurred where overcrowding, weak sanitation and limited access to medical care make containment harder. More than 5 million people are displaced across the eastern region, complicating surveillance and movement controls.

Bundibugyo virus disease is one of the recognised Ebola diseases but differs from the Zaire strain that drove several Congo outbreaks. There is no licensed vaccine or specific therapeutic approved for Bundibugyo virus, making early detection, supportive care, safe burials and infection prevention the central tools of control. Past Bundibugyo outbreaks have shown case fatality rates ranging from 30 to 50 per cent, though survival improves when patients receive early fluids, symptom management and clinical monitoring.

Health workers are facing acute risk. Dozens have been infected, and several have died, reflecting the difficulty of identifying Ebola symptoms at triage points where malaria, typhoid and other febrile illnesses are common. Hospitals not designed for viral haemorrhagic fever care have had to separate suspected cases, protect staff and keep routine services running amid shortages of protective equipment, personnel, ambulances and beds.