Clasping frail arms around his stomach, Machar Weituor doubles over in pain as he slowly positions himself over the hole in his bed. Too feeble to make it to the toilet, the 40-year-old groans faintly as he defecates into a bucket.
"I'm worried he'll die," says his wife, Nyibol Maluok, lying on the cement floor beside him. He had been carried from his village, lying on a wooden ladder, for five hours by relatives.
Twenty-four hours earlier, the couple had arrived at the clinic in Pieri, a rebel-held town in South Sudan's Jonglei state and part of what the United Nations calls "the longest, most widespread and most deadly cholera outbreak" since the country won independence in 2011.
Since this outbreak began one year ago, over 11,000 cases have been reported, including at least 190 deaths, according to the World Health Organization and South Sudan's government. WHO says 2017 shows a slight increase in cases, which coincides with the recent surge of displaced people across the country as civil war moves well into its fourth year.
The fast-developing, highly contagious infection can spread in areas without clean drinking water and with poor sanitation. It can result in death through dehydration if left untreated.
Pieri and surrounding areas in April experienced their first cholera outbreak in 21 years. Community leaders say 36 people have died in two months alone. They attribute the severity of the outbreak to an inability to support an overwhelming increase in the town's population.
Due to fighting between South Sudan's government and opposition forces in surrounding areas, Pieri's population has tripled since February. Once a town of roughly 15,000 inhabitants, it now hosts an additional 30,000 displaced people.
"People don't have soap, enough water or utensils to cook with," says Pieri's commissioner, Tot Thinkel.
The situation will only get worse without consistent humanitarian access, says Doctors Without Borders, the only foreign aid organization with a presence in Pieri.
"Displaced people are in more vulnerable situations," says Karin Fischer Liddle, the aid group's medical coordinator in South Sudan. "They are prone to outbreaks like cholera and also more at risk for malaria and other diseases because they don't have the same means of protection."
The civil war has displaced an estimated two million people inside the country and sent another two million fleeing to neighboring nations in what the United Nations has called the world's fastest growing refugee crisis.
When people flee, they often have nothing but the clothes on their backs.
When government forces attacked Chol Tut's town of Yuai in February, he says he was lucky to escape with his life. "My cousin was shot in the back by government soldiers," Tut says. "He died on the spot."
Tut now lives in Pieri, jammed into a small room with "too many people." He has no toilet and little access to food or clean water.
Humanitarians say large numbers of people living in unsanitary spaces is a recipe for disaster.
Central Pieri has only two wells serving 5,000 people. Those unable to reach the wells have started drawing water from the filthy swamps.
"This is the worst I've ever seen it," says James Khor, a lab technician in Pieri. "A lot of people have lost their lives here."
The mass displacement of people, like the civil war itself, shows no signs of slowing.
In May, Nyathak Eup buried her father and 1-year-old daughter in the same week. They both died of cholera.
"I don't know why this happened to us," says Eup, her eyes lifeless. "I think it's all because of the fighting."
Explore further: Cholera reaches South Sudan's second-largest city, UN says