Why are many countries experiencing a resurgence of measles?

Many countries are seeing more measles because some people aren't getting their shots anymore.

Sometimes, people think they don’t need a shot because they’ve never had measles before. It’s like thinking you don’t need to wear a coat if it's warm outside, you might be fine for a while, but when the weather changes, you’ll feel the cold.

When not enough people get their shots, it becomes easier for measles to spread. It’s like when kids in a playground stop washing their hands, soon everyone gets sick because germs travel from one kid to another.

Also, sometimes grown-ups forget to get their shots too, and that can make things worse. It's like if the older kids at the playground don’t wash their hands either, now it’s even easier for germs to spread!

So, when not enough people are protected, measles can come back in bigger numbers, just like a bigger group of sick kids on the playground.