William Pooley, the British nurse who survived the deadly Ebola virus, is planning to return to Sierra Leone to help fight the outbreak, a move his mother, who had hoped he would not go back, hesitantly concedes will make her "very proud".

In a Guardian interview, Pooley, 29, the first known Briton to contract the virus, called on David Cameron, who sent him get well wishes while he was in hospital, and Barack Obama, to do more to mobilise the international community to get the epidemic, raging through west Africa since March, under control.

"It's a global problem and it needs global level leadership so Obama and Cameron ... need to show some more leadership on this issue," says Pooley, while acknowledging his "huge gratitude" to the prime minister for his role in his repatriation and care. "Sierra Leone needs lots of international health-care workers working with big NGOs like MSF and Red Cross. All of that needs to be increased."

Relaxing at home in Suffolk after being discharged, virus-free, from the Royal Free hospital, in London, a week ago, Pooley is happy to have survived his ordeal but also desperate to carry on helping. Some in the profession call it survivor's guilt.

William Pooley and his mother, Jackie. Photograph: Laurence Topham for the Guardian.

"So while I'm happy to be recovered and alive, there's a lot of stuff on my mind with what's going on back there. It would be relatively safe for me to go back and work there, and it's really the least I could do having received all this amazing care and have people look after me and potentially save my life. It's the least I could do to go back and return the favour to some other people, even just for a little while.

"The more help they get the less chance there is they get sick. If they get sick they are just going to end up in a ward in Kenema with less chance than I had."

Pooley had not discussed his plans to return with his parents, but when asked how she would feel, his mother, Jackie, took a few sharp breaths. "Well, it would be his choice. We would want him to go back, not as an individual but with an organisation of some kind so he's got the backing. Obviously in a way we don't want [him] to, but I can see I would feel very proud of him if he decided he was going to, because he knows what it is going to be like."

Certainly it would be different from the state-of-the-art medical treatment Pooley received at the Royal Free, where he was treated after his emergency repatriation. There, he lay inside a polythene "patient isolator" tent, tended by dozens of staff in a unit tailor made for "category four" infectious diseases. The tent alone cost £25,000.

He was the first patient in the unit for two years. There were protocols for everything, covering food and drink to removal of materials, including body waste through heat-sealed containers. The ward's floors were colour-coded for contamination and non-contamination sides, and there was a one-way flow of people.

Stephen Mepham, the infectious diseases and microbiology consultant who flew to Sierra Leone to accompany Pooley home when he was evacuated by the RAF 18 days ago, explained that the ward kept its air at negative pressure and that it was systematically replaced because of the possibility of "aerosolisation" of particles.

Thousands of miles away in Kenema's government hospital , the contrast could not be more different – few resources and little dignity existed for the dying and convalescing patients.

Pooley says: "Those wards A and B when I first started were pretty grim. Corpses, blood, the place was really dirty – people just dying in quite unpleasant ways. When I first started there were not enough materials, there was no running water, no sheets or towels to clean a patient with. They might be incontinent, they are often confused, so you can imagine, with diarrhoea and vomiting, patients get in horrible condition.

"When I first started there was not a thing that you could use to help them. You'd just have to improvise, find a way of cleaning them and try and find something to cover them with."

Will Pooley in Sierra Leone, pictured some of the people he helped nurse to recovery. Photograph: Michael Duff for the Guardian

Death can be swift. He felt safe in his personal protective equipment (PPE) but frightened because the infection was liable to be anywhere. His first sign of illness was a sore throat. Overnight he developed aches, a headache and felt "pretty rough" but still went to work. That afternoon he was tested and he went home to await the results.

"I went to sleep and then later when it was dark I woke to [see] Ian Crozier, a wonderful doctor who is working with the World Health Organisation, out there. I woke to his voice and his voice was muffled, and when I saw he was wearing PPE I knew it was bad news.

"He was saying to me the kind of stuff I said to patients myself loads and only ever half believed. He was saying to me 'you are young, you are strong, you are going to be fine' – and it's amazing how that can reassure you."

Behind the scenes Crozier and others worked furiously on the evacuation. Two American doctors had already been airlifted out of the region. At 4 o'clock the following morning, the foreign secretary, Philip Hammond, and the health secretary, Jeremy Hunt, talked. At 6am the evacuation was confirmed. By 10am Mepham was preparing for his trip to Freetown.

Pooley still had not told his parents, delaying it until the evacuation was in progress. "Telling mum and dad about having Ebola was just horrible. It was definitely the worst thing of it all."

His father, Robin, recalls the conversation, during his cousin's wedding breakfast. "I think he said 'dad, I've got it'. I said 'you mean?' and he said 'Ebola' and there was a long pause after that."

Pooley says: "They had loads of support from the Foreign Office and things like that but it doesn't take away from the fact that I had just told them I had a 50% chance of not surviving."

He did not think a lot about "the death thing", he says. "My fear of the symptoms was perhaps worse than the fear of the death. Working in the hospital, seeing the way people die. Even here with the amazing care you get here you could still die a very horrible death."

His father coped by going into "emotional lock down". His mother said she could not let herself feel pessimistic. Buoyed by the "magnificent" treatment at the Royal Free, they gained comfort from two doctors who had worked with their son in Kenema, and from Hunt who spent an hour with them at the Royal Free.

"He brought the prime minister's warmest words with him" said Mr Pooley. "He was very supportive and warm." Robin Pooley says. "I think we did mention the fact it's not about us and it's not about Will, it's about what's happening out there [in west Africa]."

Pooley says he has been touched by the cards and children's drawings he has had from the public. A Sierra Leone family went to the hospital to give him children's drawings and thank him; another sent 50 red roses to his house, joking that he now needed to find a "Salone" (Sierra Leonean) wife.