You probably don’t have to worry much about diseases like cholera, Ebola, Lassa fever and other deadly infectious diseases. But people in developing countries do. Unsanitary conditions, natural disasters, and war help infectious diseases take hold and spread quickly. For example, violence in the Democratic Republic of Congo has displaced millions of people. Thousands have come down with cholera. Because it’s so easy to travel around the world, no country is completely safe from the spread of infectious diseases. The best way to prevent them is by stopping them in places where they begin.