DR Congo has launched an Ebola vaccination campaign for health and frontline workers in Ituri province.
The campaign began on Saturday in Bunia, one of the areas hardest hit by the current outbreak.
Health workers and other frontline staff are receiving the Ervebo vaccine.
However, the vaccine is approved for Ebola caused by the Zaire strain, not the Bundibugyo virus behind the current outbreak.
Health authorities say the vaccine could offer some protection, but researchers are still studying its effectiveness against the Bundibugyo virus.
Africanews reported the campaign, citing reporting from the Associated Press.
Ebola vaccination begins in Bunia
Authorities are prioritising people who face a higher risk of exposure to Ebola.
These include healthcare workers and other frontline staff.
The campaign is targeting Bunia and Mongbwalu in Ituri province.
Both areas have been heavily affected by the outbreak.
Healthcare worker Nikole Landu told the Associated Press that she chose to receive the vaccine because she regularly comes into contact with sick people.
Vaccine protection still being studied
Ervebo has previously proved effective against the Zaire Ebola strain.
However, the current outbreak involves the Bundibugyo virus.
Health authorities believe the vaccine may provide some protection because the viruses are related.
Researchers are still studying whether it can prevent illness caused by Bundibugyo Ebola.
Authorities are therefore using the vaccine under a compassionate-use programme.
This allows a medical product to be used during a serious health emergency even when it has not been specifically approved for that particular use.
Thousands of Ebola cases reported
Government figures cited by Africanews and the Associated Press said DR Congo had recorded 7,541 confirmed cases as of Saturday.
The figures included 3,639 deaths.
The outbreak is concentrated in Ituri province.
Authorities are responding under difficult conditions.
Insecurity, displacement, population movements and a health workers’ strike have complicated efforts to control the outbreak.
WHO approves 70,000 doses
The World Health Organization approved 70,000 doses of Ervebo for use in DR Congo, according to the report.
Around 50,000 doses are intended for health and frontline workers.
Another 20,000 doses will support a clinical trial.
The trial will study whether Ervebo protects people against the Bundibugyo virus.
The current Bundibugyo outbreak has no specifically licensed vaccine, according to the report.
Authorities had already started using Ervebo in Kisangani last month.
The wider vaccination campaign is expected to cover several health zones as authorities work to contain the outbreak.