The Ebola outbreak in the Democratic Republic of the Congo has spread to two additional health zones, with new cases reported in Bulu and Dungu, the World Health Organization said.

Bulu is in South Ubangi governorate near the border with the Central African Republic, while Dungu is in Haut-Uele province near South Sudan. The new cases bring the number of affected health zones to 63 across seven provinces.

The outbreak is being caused by the Bundibugyo strain of Ebola. As of September 23, the DRC had recorded 7,890 confirmed cases and 3,799 deaths, according to figures attributed to the WHO.

Response hindered by conflict and displacement

WHO Director-General Tedros Adhanom Ghebreyesus said the response was being complicated by insecurity, population displacement and difficulties reaching some communities.

“It’s very difficult to see Ebola in isolation because even our response to Ebola is affected by the conflict, because there is displacement and there is an access problem to some areas,” Tedros said.

Dr Jean Kaseya, director-general of the Africa Centres for Disease Control and Prevention, said contact tracing was falling far short of the level expected from the number of infections. Based on more than 7,000 confirmed cases, about 420,000 contacts should have been identified, he said, but only 30,000 people were currently on the contact list.

“When the outbreak is at community level, we cannot talk about control,” Kaseya said.

Ituri remains the main centre of infections

Ituri province remains the epicentre of the outbreak, with 6,032 confirmed cases recorded since the epidemic began in May. The province reported 868 new confirmed cases during the previous 21 days, according to the WHO figures cited in the report.

North Kivu was identified as the second most affected province, with 1,480 new cases, including 567 reported during the previous 21 days. Data cited in the report showed that nearly 60 percent of people diagnosed in North Kivu died, compared with a national average of 48 percent.

Medical staff said some patients were delaying visits to health facilities until their illness had become advanced. Dr Michel Paluku Mukuloli said fear of being sent to treatment centres was contributing to the reluctance.

“Patients think that if they arrive at the hospital, they will be immediately sent to the treatment centre to die,” he said.

The Bundibugyo strain has no approved vaccines, according to Tedros, who said the WHO was accelerating clinical trials of vaccines and treatments. Responders have also said early infections can produce milder symptoms that may be mistaken for malaria or typhoid fever.