Minnesotan Heather Buesseler has worked in Rwanda's refugee camps, volatile eastern Congo and the Philippines in the wake of Typhoon Haiyan. Yet, in South Sudan earlier in September, she witnessed perhaps the most precarious humanitarian situation in her career as a relief worker.

In the world's newest country, a major cholera outbreak has unfolded in the shadow of the deadlier Ebola epidemic in West Africa. Since the spring, 6,100 confirmed cases have claimed about 140 lives — a high mortality rate for the highly treatable disease. Buesseler, of Minneapolis, works with the Minnesota-based American Refugee Committee (ARC), which has responded to the crisis.

Since South Sudan declared independence in 2011, flare-ups of fighting with neighboring Sudan and among ethnic groups have flushed 1.5 million people from their homes. Many of them live in camps plagued by unsanitary conditions and food shortages — ideal breeding ground for cholera — amid ongoing political instability.

"It is like getting to the end of a game of Jenga," said Buesseler, 33. "There are already so many holes and gaps in the structure, you don't know how it is managing to stay standing."

Buesseler, a graduate of Macalester College, was among what ARC board member Christy Hanson calls "an international all-star team" assembled to lead its response. The nonprofit has deployed 170 "home health promoters," who offer prevention tips, soap and other supplies. ARC also set up centers where the sick can get clean water and rehydration salts, which can stop the disease early on.

New cases of cholera have waned. During her latest trip to South Sudan — her third in the past year — Buesseler focused on crafting a response plan to an emerging food crisis. Amid many challenges, she was struck by a positive energy: "You can feel the pride people have to build capacity to run their own country."

Mila Koumpilova • 612-673-4781