South Sudanese children gather at a refugee camp in Gambella, one of the poorest regions in Ethiopia. Photograph: Elissa Jobson for The Guardian
"We left all our property – our home, our goats and chickens. I ran out and this is all that I have," Nyakuom Tongyik says, pointing to the floral dress and pink scarf she is wearing. The 22-year-old is one of more than 70,000 refugees who have crossed the border into Ethiopia, fleeing fighting and devastation in South Sudan.
Her husband and father were killed when clashes erupted in their home town of Malakal, she says, sitting in her cramped, hot white tent at Leitchor refugee camp in Gambella, western Ethiopia. She escaped with two of her children, but was separated from the third amid the chaos. During the 20-day walk to the Akobo border, Tongyik's daughter fell sick. "She died on the way," she says. "There was no way to get her to the hospital."
Gambella, one of the poorest regions in one of the most food-insecure countries, was home to more than 76,000 asylum seekers from South Sudan when fighting erupted in Juba in December. The UN refugee agency, the UNHCR, is preparing to accommodate an influx of 150,000 refugees, but the government is concerned that the actual figure will be much higher.
"I don't want to exaggerate, but maybe 300,000, maybe more than that because there is no food in South Sudan and the rains start in this region in May, so people will come to Ethiopia to seek refuge," says Ayalew Aweke, deputy director of the Ethiopian Administration for Refugees and Returnees Affairs (Arra).
Refugees from South Sudan are also escaping south to Uganda and Kenya and north to Sudan, but with the onset of the rainy season, options will be limited and many more civilians will be driven towards Ethiopia. Transporting food and other supplies to the refugees will become more difficult and expensive as the few existing roads, many of them little more than dirt tracks, become impassable. Then there are the additional threats around sanitation and health – malaria, diarrhoea and cholera included.
Moses Okello, the UNHCR representative to Ethiopia, is aware of the pressing need to respond. "The rain is bringing to us an urgency, the need for us to act very, very quickly to get things in place where they are not." In response, the World Food Programme is pre-positioning 1,530 tonnes of food in the region – enough to cover the needs of 80,000 refugees for one month. UNCHR is also trying to secure the use of helicopters to help move people and provisions before the rains begin.
About 95% of those seeking refuge in Ethiopia are women and children – an unusually high proportion. "I came with many women from the village. The men went to fight. We were only women," Marsara Nyakuicak, a refugee from Gul Guk, South Sudan, says. Almost all the refugees interviewed had friends or relatives who had joined the rebel forces.
"We have heard reports of children as young as 14 and 15 being kept behind deliberately by the fighting forces on the South Sudan side," says Dr Peter Salama, a representative of the UN children's agency, Unicef, in Ethiopia.
The refugees deny forced conscription is taking place, but 19-year-old Kong Chul said he had been requested to join the White Army – a Nuer militia originally formed for cattle raiding – but no arms had been available to him.
Salama is also concerned about the number of unaccompanied minors crossing the border – more than 500 have been registered so far. Brothers Gatluak and Nhial Koang, aged eight and 10, respectively, were separated from their parents. "The fighting was very close to our village. When we saw others running we started running away," Gatluak whispers, tightly holding his brother's hand. "We don't know where they are," he says.
As the crisis continues, the physical condition of arriving refugees is deteriorating and the prevalence of malnutrition is alarmingly high. A recent survey recorded global acute malnutrition levels of almost 38%, more than double the critical emergency rate of 15%.
"We've also got huge issues with measles," Salama says. Outbreaks of the disease in South Sudan have been reported, and 60-70 cases were documented across the border in Ethiopia during the past week. Unicef, together with Arra and the regional health bureaux, is supporting a mass immunisation campaign. To date, more than 22,000 children have been vaccinated, but Salama is worried about a possible epidemic. "We have a very short, time-limited window of opportunity to scale up this operation if we are going to avoid an enormous amount of preventable deaths and disability," he says.
The response of the central and local authorities has been roundly praised. "The Ethiopia government and the people have been very generous. They have opened up their borders and allowed refugees to come into this country and this is not the first time they've done this," Okello says.
But the absorption of a huge number of people into a region with a population of about 307,000 is bound to present problems. So far, the local communities have welcomed the refugees – it helps that the exiles and their hosts are from the same Nuer ethnic group. However, Gatluak Tut Khot, Gambella's regional president, is aware of the possible tensions. "We received them peacefully,' he says. "The host community are very willing and very happy. There is no problem, but they are asking that if the town is growing there may be some contribution for the indigenous population."
Despite the strain placed on Gambella, Gatluak insists the borders will not be closed. Ayelew confirms this, and appeals for assistance from the international community. "The world knows that there is a problem in South Sudan but they don't know that people are coming to Ethiopia … Our efforts are overstretched and still people are coming," he says. "I don't know when they will stop coming to Ethiopia unless some great assistance is given in South Sudan."