At least 17 people have died in the north-west of the Democratic Republic of the Congo, where health officials have confirmed an outbreak of Ebola, the health ministry has said.

It is the ninth time Ebola has been recorded in the DRC, whose eastern Ebola river gave the deadly virus its name when it was discovered there in the 1970s, and the outbreak comes less than a year after one that killed eight people.

The health ministry said: “Our country is facing another epidemic of the Ebola virus, which constitutes an international public health emergency.

“We still dispose of the well-trained human resources that were able to rapidly control previous epidemics.”

Ebola is believed to be spread over long distances by bats, which can host the virus without dying, as they infect other animals with which they share trees, such as monkeys. Ebola often spreads to humans via infected bushmeat.

Before the outbreak was confirmed, local health officials reported 21 patients showing signs of hemorrhagic fever around the village of Ikoko Impenge, near the town of Bikoro. Seventeen of those later died.

Medical teams supported by the World Health Organization and Médecins Sans Frontières were dispatched to the zone on Saturday and took five samples from suspected active cases.

Two of the samples tested positive for the Zaire strain of the Ebola virus, the ministry said.

After DRC’s previous Ebola flare-up, authorities approved the use of a new experimental vaccine, but in the end did not deploy it owing to logistical challenges and the relatively minor nature of the outbreak.

The worst Ebola epidemic ended in West Africa two years ago after killing more than 11,300 people and infecting about 28,600 across Guinea, Sierra Leone and Liberia.

Despite regular outbreaks every few years, death tolls in the DRC have been significantly lower.