The Ebola virus can linger in bodily tissues even after the person appears to have made a full recovery, according to experts.

Parts of the body such as the eye, central nervous system and testes can harbour the virus, which can also behave in an unpredictable way.

Professor John Edmunds, from the London School of Hygiene and Tropical Medicine, said: "The Ebola virus can occasionally persist for some months in certain tissues within survivors.

"The risk of transmission from these individuals appears to be very low. However, with so many survivors in West Africa now, there is a risk that further outbreaks can be triggered, which is why authorities have to remain very vigilant."

Dr Ben Neuman, a virologist at the University of Reading, told BBC Radio Scotland he believes the outlook for Pauline Cafferkey is good.

He told the Good Morning Scotland programme: "The nice news here is that she's beaten the virus once so she can probably beat it again.

"The odds are that she actually has inherited a lucky set of genes and these are probably what protected her the first time and probably what will keep her safe the second time, regardless of any treatment. I think the outlook's good."

He said scientists are still learning about the virus and its effects.

"It seems that some of the ongoing health problems with people's eys, joints and hair loss are actually caused not by the after-effects of Ebola, but by the small amounts of Ebola which is still residing somewhere in the body," he said.

"It's surprising and we're just learning how to deal with this."

Dr Neuman said the aim of any treatment for Ms Cafferkey would be to try to eliminate any last traces of the virus.

He told BBC Radio Scotland: "The good news is that it's probably not going to be infectious. The virus, once it is removed from the blood once, tends to retreat into the hard-to-access compartments of the body.

"It will hide in places like the back of your eye, in breastmilk, places like that. But we also have some treatments now that are actually shown to work and reduce complications from Ebola and that's due to brave people like Nurse Cafferkey."

Julian Hiscox, professor of infection and global health at the University of Liverpool, said: "We know that Ebola virus can shelter in the body in what are called immune privileged sites such as the eye, central nervous system and testes.

"Due to the sheer scale of this outbreak compared to previous ones, we are going to see aspects of Ebola virus infection that we have not observed before.

"I think the persistence of the virus in asymptomatic individuals is a potential reservoir of the virus. We know that infectious virus is present in semen for a number of months. It's why men who have had Ebola and recovered are advised to abstain or wear condoms."

Dr Nathalie MacDermott, clinical research fellow at Imperial College London, said: "At present we only know of one case of viral persistence in ocular fluid in this current epidemic, which is Dr Ian Crozier, a US doctor who was treated at Emory Hospital in Atlanta.

"There are cases of acute eye inflammation in West African survivors which may have viral persistence but it has not been possible to test them yet.

"As we study more and more survivors we are identifying potential chronic problems, with viral persistence being a feature of this.

"So far we have only got definite transmission history to other people through semen."