A young man being treated in isolation at Uppsala University hospital in Sweden after suspicion of Ebola contamination does not have the disease, the regional authority has said.

Region Uppsala, which oversees several hospitals and medical clinics north of Stockholm, said a test had been carried out on the patient, who was not identified.

The young man had been in Burundi for about three weeks, and was exhibiting classic symptoms of haemorrhagic fever, including vomiting blood, according to the hospital’s chief medical officer.

The emergency clinic at Enköping hospital, where the patient was first admitted, has been closed and staff who were in contact with the patient were being looked after before the results came back negative.

An outbreak of the virus in the Democratic Republic of the Congo, which shares a border with Burundi, began in August 2018 and has resulted in 608 cases and 368 deaths. Efforts to contain the disease have been hampered by continued violence and political instability.

On Thursday, director general of the World Health Organization, Dr Tedros Adhanom Ghebreyesus, warned that the outbreak was occurring in “the most difficult context imaginable”.

He added: “To end it [the outbreak], the response needs to be supported and expanded, not further complicated. Ebola is unforgiving, and disruptions give the virus the advantage.”

To date, more than 54,000 people in DRC, including frontline responders and those at risk of having contact with the disease, have been vaccinated.

Fatality rates for Ebola have varied from 25% to 90% in past outbreaks, according to the World Health Organization.

The virus spreads from human to human through close contact with the bodily fluids of someone who has the disease.

The incubation period for Ebola – the gap between an individual being infected and showing symptoms – is up to 21 days, meaning it is possible for an infected person to travel widely before realising they have the disease.

Humans are not infectious until they develop symptoms, which at first are fever, muscle pain, headaches and a sore throat.

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, Liberia and Sierra Leone.

Cases outside of Africa have been isolated. Pauline Cafferkey, a Scottish nurse who volunteered in Sierra Leone in December 2014, was the first person to be diagnosed with Ebola in the UK.

She survived but has since been readmitted to hospital on several occasions.