A British nurse who contracted Ebola while working in Sierra Leone in 2014 was discharged from hospital in London on Sunday, five days after being admitted with complications, a statement said.

Pauline Cafferkey was successfully treated within weeks of her diagnosis but suffered a relapse in October 2015, when she became critically ill with meningitis linked to the deadly virus.

Again, she made a full recovery but on Tuesday she was admitted for a third time to the Royal Free Hospital, Britain's only isolation ward for Ebola, due to a further unspecified complication.

In a statement on Sunday, thhospital said that Cafferkey had now been discharged, adding: "We can confirm that Pauline is not infectious.

"The Ebola virus can only be transmitted by direct contact with the blood or bodily fluids of an infected person while they are symptomatic."

Experts warn that Ebola can cause ongoing problems in many survivors, although in most cases the problems seem to improve and become less frequent with time.

More than 11,300 people were killed before the World Health Organization declared last month that the two-year Ebola outbreak in west Africa was over, although Sierra Leone has since recorded new cases.