In South Sudan, millions of people have been on the run, fleeing violence since civil war broke out in December 2013. The U.N. is calling it the world's largest refugee crisis.
Health workers are on the run, too.
How do they tend to the needs of civilians in perpetual flight? Doctors Without Borders is testing a new strategy: a "runaway bag."
It's a backpack made of waterproof canvas and weighing about 12.5 pounds when fully packed. What's inside? Antibiotics, painkillers, anti-malaria medicine (and a rapid test), material to bandage wounds, oral rehydration solution, water purification tabs and a pen and a register to record what has been handed out.
A single bag is meant to carry enough supplies to treat 50 to 70 people over a period of about two weeks, says MSF, the abbreviation for Medecins sans frontieres, as the group is called in French. The idea is to enlist local staff to carry the bags if a mass evacuation occurs.