Hippos and humans in Africa often live near each other. Hippos prefer to live in the slow-moving fresh water of rivers and lakes with nearby grassy lands where they can eat. These are exactly the same kinds of places where humans want to live. Unfortunately, hippos and humans are not always friendly neighbors. No official statistics are kept, but hippos are often reported to kill more people in Africa each year, than any other animal.
Hippos don't eat people. They're strict vegetarians. People are often killed when they are bitten or trampled by the hippos. The trouble usually comes for one of two reasons.
1) Boating accidents - A hippo can fall asleep while resting underwater. In the same way we roll over while we are asleep, a hippo will lift it's nose above the water about every five minutes without even waking up. People in canoes passing by a sleeping hippo may never know a sleeping hippo is in the river until they whack it with a paddle. (Waking a sleeping hippo by whacking it with a paddle is never a good idea.)
2) Encounters at night - The only time hippos move far from the water is at night when they go to feed. People in Africa don't have many of their roads lit up by street lights. Unless there is a full moon, there may be little light at all. Often, people don't realize they are about to cross paths with a feeding hippo until it's too late. Hippos may charge if they are startled by a person passing in the dark. (Startling a hippo in the dark is also never a good idea.)