What causes flu pandemics?

Flu pandemics happen when new flu viruses come into our lives and spread really fast.

Imagine your favorite toy is suddenly taken by a new friend who doesn’t know how to share. That’s kind of what happens with the flu. The virus is like that new friend, it's not someone we've met before, so our body doesn't know how to stop it right away.

The flu virus lives in people and spreads when they cough or sneeze. It’s like a tiny, invisible airplane ride from one person to another, sometimes across the whole world!

A pandemic happens when this new flu virus starts spreading everywhere quickly. Think of it like a big game of tag, everyone is running around catching the virus and passing it on. That’s why so many people get sick all at once.

Sometimes, these viruses are even stronger than the ones we’re used to, which makes them harder for our body to fight off. It's like when you're playing soccer and suddenly there are three new players joining in, your team has a hard time keeping up!