A new case of Ebola has been identified near the city of Butembo in eastern Democratic Republic of the Congo (DRC), three months after the country announced an end to the virus.

This new case marks the start of Congo’s twelfth Ebola outbreak since the virus was discovered near the Ebola River in 1976.

The new case, a woman, died of the disease, the health ministry said on Sunday.

The woman was found with symptoms of the virus in the town of Biena on Feb. 1 and died in hospital in Butembo on Feb. 3.

She was married to a man who had contracted the virus in a previous outbreak. It was not yet clear if the case marks the start of a new outbreak or if it represents a manageable flare-up from an outbreak in the region that killed over 2,200 people between 2018 and 2020, the second-most in the disease’s history.

“The provincial response team is already hard at work. It will be supported by the national response team which will visit Butembo shortly,” the ministry said in a statement.

More than 70 people who came into contact with the dead woman have been tracked and the places she visited are being disinfected, said the World Health Organisation, which is helping with the response.

Samples have been sent to Kinshasa to confirm the link to the previous outbreak.

“It is not unusual for sporadic cases to occur following a major outbreak,” the WHO said in a statement.

Congo’s equatorial forests have been a breeding ground for the Ebola virus, which causes severe vomiting and diarrhoea and is spread through contact with body fluids.

The country has experienced 11 outbreaks since the virus was first discovered near the Ebola River in 1976, more than double any other country.

The emergence of more cases could complicate efforts to eradicate COVID-19, which has infected 23,600 people and killed 681 in Congo. A coronavirus vaccination campaign is expected to start in the first half of this year.

However, an Ebola vaccine and a well-drilled health system mean the country is better placed than ever to deal with outbreaks, even in urban settings. Ebola has a much higher death rate than COVID-19, but unlike coronavirus, it is not transmitted by asymptomatic carriers.