Ebola nurse Pauline Cafferkey 'flown to London Royal Free hospital'

Pauline Cafferkey was diagnosed after returning from helping victims in Sierra Leone

Nurse Pauline Cafferkey (PA)

The British nurse who contracted the Ebola virus while working in Sierra Leone has been redamitted to hospital after falling ill for the second time.

Pauline Cafferkey was admitted to the London Royal Free hospital because of "an unusual late complication of her previous infection by the Ebola virus".

Ebola 'very low risk' to UK

Greater Glasgow health board confirmed that the Ebola virus was still present in Ms Cafferkey's blood but it was left over from the original infection and is not believed to be contagious.

People who have come into close contact with her are being monitored as a precaution but are not thought to be at risk.

The Royal Free Hospital in London where Ms Cafferkey is being treated (PA)

Dr Emilia Crighton, NHSGGC director of public health, told the BBC: "Pauline's condition is a complication of a previous infection with the Ebola virus.

"The risk to the public is very low. In line with normal procedures in cases such as this, we have identified a small number of close contacts of Pauline's that we will be following up as a precaution."

Ms Cafferkey visited 10 Downing Street just 10 days ago to meet the Prime Minister's wife, Samantha Cameron, to receive her Pride of Britain award alongside the other nurses and health care workers who contracted the illness while volunteering in West Africa.

She had been volunteering with Save the Children during the outbreak and returned to Heathrow in December last year when she began exhibiting symptoms.

Ms Cafferkey was held in isolation for a month in the hospital's specialist unit.

Pauline Cafferkey (third from left at the back) with Samantha Cameron and other Pride of Britain award winners at the reception in Downing Street

Officials say the 39-year-old's transfer to London is "highly precautionary".

It comes as the three countries at the centre of the outbreak - Sierra Leone, Guinea and Liberia - recorded their very first week without a new case of the disease being diagnosed since an outbreak was declared in March 2014.

The three countries will have to wait 42 days with no new cases reported before it can officially be declared "Ebola free".

According to the World Health Organisation, more than 11,000 people are estimated to have died in the outbreak.

But 10 people in the south Nigerian city of Calabar have recently been quarantined in a fresh scare for the country which had originally been declared "Ebola free" in October 2014.