The Ebola outbreak in the Democratic Republic of the Congo (DRC) may be caused by a mutating virus, health officials fear, as confirmed cases have surpassed 4,000. The Africa Centres for Disease Control and Prevention (Africa CDC) announced a major escalation in response, including door-to-door searches for patients.
Unprecedented severity
Dr Jean Kaseya, director general of Africa CDC, told a press briefing on Thursday that cases had topped 4,000. The outbreak, caused by the Bundibugyo strain, was first reported on 15 May, though it may have been spreading since January. As of 4 August, there have been 3,973 cases and 1,801 deaths, according to the DRC's national public health institute.
This is now the second-largest Ebola outbreak on record. There are eight times more cases and six times more deaths than were recorded 11 weeks into the West Africa Ebola outbreak (2014-18), which infected over 28,000 people and killed at least 11,000.
Kaseya said he had spoken with Dr Tedros Adhanom Ghebreyesus, WHO director general, and they planned studies “to check if there is no additional issue, or maybe if the virus is not mutating. Because the level of severity of this Bundibugyo outbreak is unprecedented.”
Untracked transmission
More than two-thirds of Ebola deaths are occurring in the community, not in treatment centres. In an MSF-run centre in Bunia, capital of Ituri province, 90% of admitted patients do not appear on authorities' lists of contacts of known cases. Both factors indicate high levels of untracked transmission.
Contact tracing in the DRC is insufficient, with only 10 contacts identified per Ebola patient, when about 40 would be expected, Kaseya said.
Ebola is a viral haemorrhagic fever causing vomiting, diarrhoea, organ damage, and internal bleeding. The outbreak is centred on the conflict-affected mining province of Ituri, but has spread to Nord-Kivu, Sud-Kivu, Haut-Uele, and Tshopo. Uganda recorded 20 cases before bringing its outbreak under control.
Door-to-door search
Dr Wessam Mankoula, acting head of emergency preparedness and response at Africa CDC, said response teams planned to shift “from contact tracing to active case search,” with community health workers “moving from door to door” asking households about anyone sick with Ebola symptoms. He added: “I think the time for incremental action is over and we're starting now the phase for scaling up.”
Kaseya promised a “village-centered response” involving communities, more use of digital tools, and greater action in camps for internally displaced people.
New treatments and vaccines
Officials plan to begin using antiviral remdesivir on a compassionate use basis. They will also test whether Ervebo, a vaccine licensed for a different Ebola strain, should be offered in the affected province, after data suggested Bundibugyo caused less serious disease and “zero death” among those vaccinated.
“Seeing the expansion of this outbreak, only the public health measure will not be enough to quickly control or stop this outbreak,” said Dr Placide Mbala Kingebeni, Africa CDC director of research, clinical trials and innovation.
DRC authorities are investigating a suspected Ebola death on a boat heading to Kinshasa from the north-east; other passengers will be quarantined and tested.
Impact on healthcare
Unicef warned that essential healthcare is being disrupted as fear and service disruptions keep families away from clinics. In the outbreak's centre, the mining town of Mongbwalu, the proportion of children receiving their first measles dose has fallen 69%.
