In a small village, a girl named Amina loves to swim in the river. But swimming here has a risk. The water is not always safe.
One day, Amina feels very sick. She has a bad illness. Her stomach hurts and she is always tired. Her mother is very worried and takes her to a doctor.
The doctor tells them the river water can be dangerous. There are tiny animals in the water that make people sick when they swim.
Many children in the village have the same problem. Helping all the sick children is a very big and difficult job for the doctors.