What are emerging infectious diseases?

Emerging infectious diseases are new or changing illnesses that start to affect more people.

Imagine you're playing with your toys in the park when suddenly a friend comes over and starts sneezing, and then you start feeling yucky. That’s kind of like what happens with emerging infectious diseases. They’re illnesses that either didn’t exist before or were around but are now becoming more common.

Sometimes, these illnesses come from animals. For example, a virus might live in bats and then jump to humans, just like when you catch a cold from your brother who sneezed on you!

These diseases can spread quickly if people don’t know about them. It’s like when you spill juice on the floor and everyone in class starts slipping, suddenly, it's a big mess! Scientists watch out for these new illnesses so they can help stop them before they become too big of a problem.