Health workers in Democratic Republic of Congo will begin a vaccination campaign on Monday aimed at containing an outbreak of the deadly Ebola virus, a spokeswoman for the health ministry said.

Jessica Ilunga said 4,000 doses of vaccine were shipped on Saturday to Mbandaka, which last week registered the first cases in an urban area since the latest flare-up of the disease was announced earlier this month.

Cases in Mbandaka, a port city on the Congo river, have raised concerns that the virus could spread downstream to the capital Kinshasa, which has a population of 10 million.