The first case of Ebola has been confirmed in Goma, now the biggest city to have been affected by the disease since its outbreak in the eastern Democratic Republic of the Congo last August, the health ministry said on Sunday.

The discovery has raised concerns the virus could spread quicker in the densely populated area close to the Rwandan border.

A sick man had arrived in Goma early on Sunday by bus with 18 other passengers and the driver from Butembo, one of the main towns touched by Ebola in Nord-Kivu province.

The man was tested “and the results of the laboratory test confirmed that he was positive for Ebola,” the ministry said in a statement.

It added that his trip began on Friday after “the first symptoms appeared on July 9 (Tuesday)”.

“Given that the patient was quickly identified, as well as all the passengers on the bus from Butembo, the risk of the disease spreading in the city of Goma is low,” the ministry said.

The passengers and the bus driver will begin getting vaccinations on Monday, it added.

Goma is located south of where the second-largest Ebola outbreak on record was first detected a year ago.

The disease outbreak in the eastern region has so far killed 1,655 people and 694 have been cured, according to a health ministry bulletin on Saturday.

And 160,239 people have been vaccinated, it added.

But efforts to tackle the crisis have been hampered both by militia attacks on treatment centres, in which some staff have been killed and by the hostility of some local people to the medical teams.