Health officials in the UK say a total of 58 close contacts of a British nurse - who is being treated for a late complication of the Ebola infection - are being closely monitored.

Pauline Cafferkey is being treated in an isolation unit in London.

She was diagnosed with Ebola in December after returning from Sierra Leone - but fell ill again last week.

Ms Cafferkey was transferred from the Queen Elizabeth University Hospital in Glasgow to the Royal Free London hospital on Friday in a military aircraft under supervision.

In a statement, the Royal Free said she is in a serious condition.

"She will now be treated in isolation in the hospital's high-level isolation unit under nationally agreed guidelines," the statement read.

"The Ebola virus can only be transmitted by direct contact with the blood or bodily fluids of an infected person while they are symptomatic so the risk to the general public remains low and the NHS has well established and practised infection control procedures in place".

The nurse was first diagnosed with Ebola in December last year and spent almost a month in isolation at the Royal Free before being discharged in January.

She was treated with an experimental anti-viral drug and blood taken from survivors of the disease.

Her complications come after the three West African countries at the centre of the Ebola epidemic recorded their first week with no new cases since the outbreak was declared in March 2014.

More than 11,000 people have died in Guinea, Liberia and Sierra Leone, according to figures from the World Health Organisation (WHO).