At a small health clinic in the Kutupalong refugee camps in Bangladesh, Somadu Katu is clutching her 3 ½-year-old son, Yassin.
Yassin is wailing. He's running a fever and there are small red dots all over his body. Katu is terrified.
"I'm scared because my baby is very young so he is not able to tolerate the pain," Katu says.
Katu says her son started getting sick about four days earlier. At first, the 35-year-old Rohingya mom thought it was just a common cold. And then the menacing rash emerged.