The hospital staff knew him simply as 'David'. The six-year-old Sudanese boy had been left a paraplegic after nomads shot him in the spine as they tried to steal his parents' cattle. David had languished for six months in the hospital at Lokichoggio, near Kenya's northern border with Sudan, by the time Hong Kong surgeon Fan Ning arrived last November. By then, David had become listless and unhappy. His future was bleak, with the boy facing the prospect of life in a wheelchair or in the confines of his village. After Dr Fan, a Red Cross volunteer, returned to Hong Kong in March, David's mother decided to take her son home to an uncertain future in their small village in southern Sudan. The boy's plight is typical of that faced by many young victims of Africa's wars. On the continent, paraplegic patients face a high risk of developing further complications, such as pneumonia and bed sores, if they don't receive proper medical care. 'These kinds of problems can easily kill a patient. In Africa, when you leave the hospital it's usually the end,' said Dr Fan, 36. Dealing with tragic cases, such as David's, is part of the job description for Dr Fan and his fellow Hong Kong aid workers. They represent a small, dedicated group, who travel to far-flung regions to treat the sick and help rebuild the lives of the world's most impoverished people. Along the way, they witness horrific and distressing scenes that can leave long-lasting emotional scars. Aid agencies do their best to prepare their staff for the trauma they may encounter and cope with the myriad mental snapshots of human suffering. It's unlikely Dr Fan, who works at Yan Chai Hospital in Tsuen Wan, will ever know what happens to David or the numerous other patients he treated during his four-month stint in the dilapidated and under-resourced Kenyan hospital. His experiences there underscore the desperate need for help among the homeless and dispossessed in strife-torn parts of Africa such as Sudan, where the UN estimates 200,000 have been killed and 2.5 million have been displaced since 2003 in fighting between rebels, the Khartoum government and its allied Arab militia. Dr Fan tells chilling tales of his work there treating children with horrific burns from cooking in primitive village conditions, the victims of spear attacks from tribal conflict, and the many Aids sufferers, among the millions who have died from the disease on the continent. In Kenya, one in 20 pregnant women is at risk of dying from complications. Dr Fan said he often operated on women who had been in labour for days before arriving at the hospital. 'Usually when they arrive the baby is dead or the leg or hand has come out but already there's no sign of life,' he said. A shortage of resources is a major challenge for doctors in developing countries, but Dr Fan said medical knowledge was not the most important quality for aid workers. 'What I think is most important is ... whether you can cope with the stress. Before we can manage the patient we have to manage ourselves,' he said. Hong Kong executive director of Medecins Sans Frontieres (MSF), Dick van der Tak, 44, gives a similar account of the trauma faced by colleagues in the field. Mr van der Tak's 12 years with the organisation has spanned two continents and six countries. He knows the difficulties of coping with other people's suffering and can recognise the warning signs when colleagues need help. Mr van der Tak was thrown in at the deep end on his first assignment, to Africa's Great Lakes region in 1994. Two days after finishing his induction course, Mr van der Tak, a lawyer by training, was on a plane to Burundi where refugees were flooding in, escaping the genocide in neighbouring Rwanda. Estimates of up to 800,000 people, both Tutsis and Hutus, were killed, many hacked to death during a spree of violence that was largely ignored by the rest of the world. After four months in Burundi, Mr van der Tak was among the first MSF staff to enter Rwanda after the violence subsided. His team took over a destroyed hospital in Ruhengeri, on the Rwanda-Uganda border. The hospital compound was littered with booby traps and mines. 'What was nerve-racking was looking in people's eyes, people who had seen the genocide,' he said. 'I remember having that feeling of not knowing who was a killer and who was a victim and that led to very uncomfortable situations.' Witnessing the aftermath of such an atrocity took its toll. MSF ordered Mr van der Tak to return home to the Netherlands after 18 months in the field. He was initially angry at the decision and tried to convince his supervisor to let him stay, but now says it was the right move. 'I was in bad shape. I worked too much, too long,' he said. He was having trouble concentrating and that started to affect his judgment. 'I became a risk to myself. I became a risk to the team.' Mr van der Tak, who said he 'cried and cried' as his plane flew out over Africa on his homeward journey, then he saw a psychologist about six times during his sabbatical, before he was despatched to Bangladesh for his next assignment. 'It helped a lot to vent, to have somebody you could trust and understand and listen,' he said. Adding to the stress of field work, staff in conflict zones must be aware of troop movements, curfews and local customs, and they know that even the most diligent precautions cannot protect them from becoming targets of violence on occasion. In 2002, a Dutch aid worker was kidnapped in Dagestan and held for 550 days, and an American worker in Chechnya was kidnapped and held for a month in 2001. On June 2, 2004, a date etched in Mr van der Tak's memory, five MSF workers were killed when their car was ambushed as they drove through a remote area of Afghanistan. It's still not clear who was responsible for the killings and MSF is yet to resume its operations in Afghanistan. The agency usually suspends operations and evacuates international staff after a kidnapping or killing in a region. 'It's extremely difficult and traumatic,' Mr van der Tak said from his office in Mei Woo. To safeguard their mental well being, MSF staff take 'R and R' every six weeks. The organisation tries to arrange activities in the field to give staff a sense of normality, such as cooking or watching a movie. They're encouraged to keep a diary as a way of dealing with stress. When they return from their assignment, staff are given a debriefing and have the option of seeing a psychologist. Before going abroad, Hong Kong Red Cross volunteers complete a training course that includes security and psychological issues. The Red Cross sends them 'comfort materials' in the field, such as CDs, videos, chocolates or Christmas cards 'just to let the delegate know that we care about him or her', said Bonnie So Yuen-han, head of the organisation's International Relief Service in Hong Kong. Staff visit the in-house psychologist before and after assignments, and those who work in conflict zones are particularly urged to attend counselling. The majority of delegates cope well, but Ms So said it was vital to have psychological support for those who needed help. Mr van der Tak said people coped with the trauma in different ways. Some cried; others resorted to black humour. It's most dangerous when people become immune to the suffering. When that happens, it's time to leave. 'I think it's very dangerous if you're no longer touched by what you see around you, and it happens,' he said. Mr van der Tak still bears the psychological scars of his tours of duty. He recalls a trip to the theatre in Amsterdam when actors started throwing buckets of red paint to symbolise blood. 'I left because I simply could not see it. The experience I had gone through in Rwanda was too fresh,' he said. For Hong Kong nurse and MSF volunteer in Sudan, Eunice Wong Wing-kwan, the weekly phone calls with her family, and keeping a journal, helped her to manage the emotional strain. Amid the horrors she witnessed after arriving in Sudan late last year, one that sticks in her mind was from the seven months she spent in the town of Kerenek, in west Darfur, where she met a nine-year-old boy she knew as Abbass. When he arrived at the hospital, Abbass weighed just 19kg. 'He could not pass urine for two days. He could not eat or drink anything,' said Ms Wong, 29. After two weeks of intravenous feeding, Abbass could play with other children, and after another two months he was well enough to go home. Ms Wong told his father as they left that it was vital he bring the boy back for checkups. But when Abbass and his father finally returned to the hospital two months later, there was no trace of the healthy, happy little boy she'd last seen. The malnutrition in western Sudan meant Abbass' condition was much worse than before and he could no longer walk or talk. After two days in hospital Abbass died. It wasn't until after his family started their three-hour journey home, carrying Abbass' body on a donkey cart, that Ms Wong finally gave in to her emotions. 'I couldn't control myself. I cried in the dressing room,' she said. Another trauma she encountered was the widespread rape of women in battle-torn Darfur, which prompted Ms Wong to set up a counselling service during her time there. Most of the women she treated were attacked as they went to fetch firewood. Many had not told their families about the attacks because of the shame associated with sexual assault. 'They are brave to ask for help,' Ms Wong said. 'They don't ask for a lot of counselling. They just want to have somebody to listen to them.' Ms Wong returned to Hong Kong in June and now works at the Prince of Wales Hospital. However, she wants to go back in the field, and says the experience has taught her to value every moment of her life. For Dr Fan, his time in Kenya was the first chapter in what he hopes will become a lengthy engagement with the developing world. He says that living in an affluent city such as Hong Kong, it's easy to forget how people on the other side of the world are struggling to secure life's basic necessities. 'When you are removed from them you easily forget these kinds of things,' he said. 'I think the most important thing is to remind ourselves.' To donate to Medecins Sans Frontieres, call 2338 8277 or visit www.msf.org.hk . To donate to Red Cross, call 2802 0021 or visit www.redcross.org.hk