A Scottish nurse who contracted Ebola while working in Sierra Leone has been discharged from hospital after making a complete recovery.

Pauline Cafferkey is now free of the virus after more than three weeks in a hospital's high level isolation unit (HLIU), where she was critically ill for a time.

She said she is "happy to be alive" and thanked staff at the Royal Free Hospital in London who she said "saved my life".

Ms Cafferkey was diagnosed with Ebola after returning to Glasgow and was initially admitted to the city's Gartnavel Hospital on December 29, then transferred to the Royal Free the following day.

The 39-year-old was discharged from hospital today and praised the infectious diseases team who cared for her, led by Dr Michael Jacobs.

She said: "I am just happy to be alive.

"Thanks to Dr Mike and his amazing team of doctors, the matron, the nurses and all the other people that I didn't meet working behind the scenes to keep things going.

"They were always very reassuring and I knew I was in the best hands - they saved my life.

"I'm definitely going to keep in touch, I've got a strong bond with the place and I'll be sad to leave but I want to go home."

The nurse, from Cambuslang in South Lanarkshire, had volunteered with Save The Children at the Ebola Treatment Centre in Kerry Town before returning to the UK.

She flew back to the UK via Casablanca in Morocco. Her temperature was tested seven times before she flew from Heathrow to Glasgow and she was cleared to travel.

Ms Cafferkey said she initially thought she might have a urine infection when she returned from Sierra Leone, and did not feel unwell until she went to bed that evening.

She later became feverish and followed advice given to her at Heathrow to contact local services.

She was admitted to an isolation facility at the Brownlee unit in Gartnavel Hospital at 8am on December 29.

After a blood sample tested positive for Ebola, she was transferred in a military plane to the Royal Free Hospital by 8am on December 30.

While in hospital she was treated with convalescent plasma taken from the blood of recovered European patients and the experimental anti-viral drug ZMabb, which is not the same as ZMapp, which was used to treat the British nurse William Pooley.

Ms Cafferkey said she has "no idea" how she caught the virus, which has killed more than 8,000 people in West Africa.

She is now rebuilding her strength and can walk for short amounts of time.

The community health visitor nurse said: "I'm looking forward to going home, I just want to see my friends and family - I'm looking forward to having a bath, I haven't had one for some time now.

"I just want to get back to normal, get my strength back as I've lost a lot of weight and eventually returning to work, obviously that's going to take some time. I've got a great job, I'm working with babies under the age of five.

"I'll be having a break from aid work and I've no plans to return to it at the moment, but who knows in the future?"

Ms Cafferkey thanked the Royal Free Charity, which donated an iPad for her to use while she was in the unit.

She said: "As I was beginning to recover, I listened to lots of music when I was in the HLIU and that was a massive help.

"I also had lots of Irn-Bru to help me through!"

Dr Jacobs said: "We are delighted that Pauline has recovered and is now well enough to go home. I am very proud of the staff who have been caring for her. It is because of the skill and hard work of the entire team that she is now able to go home."

Save The Children has launched an investigation into how Ms Cafferkey was infected but admits it may never establish the exact circumstances.

The Royal Free Hospital has the UK's only HLIU, which is run by a dedicated team of medical staff.

The unit is designed to ensure staff can safely treat a patient with a dangerous infectious disease.

Access to the unit is restricted and there are a number of measures in place to ensure the virus is contained.

Health Secretary Jeremy Hunt said: "I am delighted that Pauline Cafferkey has been discharged from hospital and can now return home. Her selflessness and courage are remarkable and she represents the very best of NHS values.

"I would like to thank all the staff at the Royal Free who have worked tirelessly to provide her with world class care and treatment."

Professor Dame Sally Davies, Chief Medical Officer for England, said: "It is wonderful to hear that Pauline Cafferkey has recovered. This is testament to the hard work and dedication of the team at the Royal Free who have worked around the clock to help bring about this happy outcome."

In an interview with the BBC, Ms Cafferkey remembered the moment when she was told she had the virus.

She said: "I had a lovely doctor with me who had the horrible job of breaking the bad news to me. She sat with me for a while and she did say to me 'how do you feel?', and I just said 'well I've got a battle on my hands', which I did."

Asked whether there was a point at which she thought she might not make it, she said: "There was a point which I remember clearly saying, I don't remember which doctors were with me, but I do remember saying 'that's it, I've had enough'."

She has had more than 100 letters and cards from well-wishers since falling ill.

Scotland's First Minister Nicola Sturgeon said: "I am delighted to hear that Pauline Cafferkey has now been discharged from hospital.

"Ebola is a terrible disease, and the fact that she has made this recovery is a tremendous tribute to the work of the NHS staff who have been committed to her care over the last few weeks. Like all her fellow volunteer health workers she has shown tremendous bravery in going to west Africa to help tackle the Ebola outbreak.

"I hope that she will now be given the time and space she needs to recuperate after her illness."

International Development Secretary Justine Greening said: ''I am absolutely delighted that Pauline Cafferkey has been successfully treated for Ebola and today was discharged from the Royal Free Hospital.

''All of our thoughts have been with her and her family during her recovery and this is fantastic news.

''Pauline and all of the NHS volunteers helping to contain, control and defeat Ebola are making a huge difference in the fight against this horrible disease. Their hard work is saving lives and they have the thanks of the UK and Sierra Leone alike.

''My thanks also to the staff at the Royal Free for all their help in getting Pauline well.''

NHS England chief executive Simon Stevens said: "I am delighted for Pauline Cafferkey and her family and I would like to pay tribute to the team at the Royal Free who have worked so hard to treat her.

"I would also like to applaud the professionalism and dedication of all the NHS volunteers in West Africa who have put themselves at risk to help fight Ebola. The work that all these doctors and nurses perform demonstrates the values of the NHS in action and we are all exceptionally proud of their efforts."

During the BBC interview Ms Cafferkey recalled the progress of her illness.

She said: "The first few days I was very strong and felt absolutely fine. Then day three or four I did start to get symptoms and things, and then I started deteriorating.

"I pretty much lost a week of my life that I just can't remember. I remember having a discussion with my sister, because we had to speak via telephone because I was in a tent, and I was saying 'oh that's me been here a week now' and she was saying 'no you've been here two weeks', and I was saying 'no, it's a week I've been here', and then just realising I've lost a week of my life at some point."

She said that she is looking forward to seeing her friends and family and going for a walk along the beach when she is strong enough.

Asked how the experience has changed her perspective on life, she said: "Many people would say 'I'm going to go out there and live life now' but I was doing a pretty job at that before all this."

Save The Children chief executive Justin Forsyth said: "We are delighted for Pauline Cafferkey and her family that she has fully recovered from Ebola. Pauline is a dedicated humanitarian who worked tirelessly and selflessly in the fight against Ebola.

"Despite the risks to her own safety, she volunteered to use her nursing skills to help save lives and treat those in dire need in Sierra Leone. The bravery of Pauline and everyone who has worked to defeat Ebola makes us even more determined to redouble our efforts to beat the disease."

Prime Minister David Cameron said: "It's great to see Pauline Cafferkey looking so well after her battle with Ebola.

"She's been extraordinarily brave."