On Sunday, aid worker Jeremiah Young couldn't tell if he was hearing thunderclaps or bombs.

That's the scene in Juba, capital of South Sudan. Rainy season has begun. And intense fighting broke out on Thursday — a new round of fighting between supporters of the vice president and troops backing the president. Heavy gunfire was exchanged, along with mortar and grenade explosions.

As the conflict erupted, an estimated 30,000 people fled their homes, seeking safer ground. Another 30,000 had previously sought shelter in what's called a "Protection of Civilian" site in the city that's run by the U.N. There were reportedly more than 150 deaths.

Amid this burst of conflict and chaos, aid groups struggle to function. Goats and Soda spoke to Young, who works for World Vision, and Leslie McTyre, a program coordinator for the International Medical Corps, about the challenges of providing humanitarian aid.

One of World Vision's goals is to make sure people have food and clean water and a safe place to stay. Even before this round of fighting, an estimated 3.9 million individuals in South Sudan didn't have enough food to meet their nutritional needs, says Young. The situation in Juba will only make the number go up, he predicts. In such emergency situations, "high-energy biscuits" are a go-to food to distribute. They're fortified to provide calories and nutrition, says Young.

With the emphasis on such lifesaving activities, says Young, other kinds of help that World Vision offers — education for the children of displaced families, for example — may lapse. The International Medical Corps, based in Los Angeles, runs a hospital in the Protection of Civilian site; its maternity wing was shelled on Monday and two employees were injured. When the international airport reopened, the group sent home its 19 international employees because of safety concerns. McTyre, who is from Fairfax, Va., is one of the few who stayed to assist the South Sudanese staff.

There's an overwhelming amount of work to do. The hospital is seeing an influx of patients."People with severe trauma, a number of raped women, people that have gotten hurt running from the fighting," McTyre says. Plus, the usual arrival of people who have fallen ill.

"I'm trying to figure out how to get our staff some rest," says the 67-year-old McTyre. "They're working around the clock. They ran out of water two days ago. I don't know what they're doing about that. I finally got a water truck going over there — that should help a bit."

Asked what he needs, McTyre rattled off a list: dressings, fluids to hydrate patients, trauma kits with antibiotics, rape kits "with pills that would take care of infections and pills that would take care of unwanted pregnancies and a number of items that help to soothe and calm the patients down."

Under ordinary circumstances, one rape kit serves one person. "In conditions like this we have to split them up between four different women," McTyre says.

Despite the difficult times, neither he nor Young has lost hope.

Young is 28 and from San Diego. This is his first overseas assignment for World Vision. He has been in South Sudan for 10 months now, working on peace-building programs. He says: "I see hope in the eyes of the children, and that's the motivation for us to continue doing what we're doing. We see hope in the eyes of mothers and fathers for their children, whom they want to live a better life than they have lived."

But he also worries about the future: "If we do not provide the necessary support for these children to develop as a child should, then it truly will be a lost opportunity."

McTyre suspects that "we've seen the worst — there may be other flare-ups to come but not as bad as what we just weathered through." The South Sudanese people he knows "are fed up with the fighting," he says. He sees enthusiasm for reconciliation efforts. But healing will not happen overnight, he cautions: "Donors and donor countries need to open up their pockets because this is going to take some time to repair the wounds."

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