Ebola reaches New Congo region as contact tracing breaks down

(Bloomberg) — Ebola has reached a health zone more than 100 miles from the mining town where the outbreak in the Democratic Republic of Congo is believed to have started, as rescue workers trace fewer than 40% of known contacts in the worst-hit province.

Health workers in Ituri province, which accounts for nearly 94% of confirmed infections, actively monitored only 39.3% of identified contacts, the country’s National Institute of Public Health said in a report on Tuesday. The newly affected Mambasa health zone lies southwest of the town of Mongbwalu, believed to be the origin of the outbreak, bringing the total number of affected health zones nationwide to 24.

The outbreak – caused by the rare Bundibugyo virus – has become one of the most complex Ebola outbreaks in recent years, spreading through a conflict-torn region where insecurity, population movements and mistrust of authorities undermine efforts to identify contacts and isolate cases. At the same time, health professionals are struggling to make sense of rapidly changing surveillance data.

More than 4,000 contacts are now being traced in the three affected provinces, although surveillance teams have reached less than half, according to the report.

Neighboring Uganda also confirmed six new cases on Tuesday, bringing the total to 15, including one death.

Responders in Congo cleared the lab backlog that had built up in recent days and analyzed all 76 samples taken on Monday. Almost a third tested positive for Ebola.

Congo has now reported 344 confirmed infections and 60 confirmed deaths from Ebola. The death toll rose from 48 reported on Monday after officials updated figures in North Kivu province, where delays in treatment, deaths in the community and patients fleeing care contributed to the unusually high death toll.

On June 1 alone, 23 new confirmed cases were reported, including 11 in Mongbwal and six in Bunia, the Ituri capital.

“The escape of four confirmed cases – one in Ituri and three in North Kivu – poses a high risk of community transmission and continued spread of the epidemic,” the report said.

Community opposition remains a major obstacle to restrictions. Red Cross teams carrying out safe burials were attacked and beaten at the cemetery, the report said, while authorities continued to encounter resistance in their search for contacts in Bunia and Nizi, a mining town about 25 miles north of the city.

Health officials have also documented persistent rumors that traditional healers possess herbal remedies for Ebola, and warned that some communities fear other vaccination campaigns could be mistaken for efforts to spread the virus.

While officials said preliminary data indicated transmission in the community may be declining, they cautioned that the numbers remain incomplete.

Separately, licensed Ebola vaccines can induce partial immune responses against the Bundibugyo strain, according to a preprint released last week.

Detectable cross-reacting antibodies against Bundibugyo Ebola were found in samples from a large West African vaccine trial, although at significantly lower levels than against the Zaire strain targeted by the shots, researchers at the Institute for Vaccine Research in Paris said. The findings have not yet been reviewed.

More such stories are available at bloomberg.com