So they want to be in and out as soon as they possibly can - if they can get away with not washing their hands they will.
So how do we get these little ones to make it a habit?
If I had a dollar for the number of times I have said "wash your hands" over the years I would be rich. First to my children, who as adults have very good hygiene habits and now to my grandchildren who are learning.
Repeating it over and over does work, but out of sight and out of mind.
At school it is impossible for teachers to enforce the hand washing rule.
They can stand in front of a class full of children, tell them about the importance of washing their hands but they certainly can't be on there to see what happens in ablution blocks.
It's up to parents to hammer the message home. Maybe someone needs to come up with a ditty as they did with making sure children were "buckled up".
My grandchildren are quick to tell me if I move off in the car and they aren't buckled in - "wait, I'm not buckled up".
There was a huge campaign around safety for children in cars and most parents and children wouldn't dream of driving around without buckling up.
The consequences of not wearing a seatbelt in a car can be fatal, a bit different to not washing hands.
However, as our population grows and these bugs seem to get more rampant, hygiene is really important. And it's not just children, some adults are not so good at washing their hands either.
So how about this ditty "bug off" - maybe not - a wee bit close to another word not fit for youngsters. How about "wash it off" - boring - this one from a colleague is good "drown the germs" - I like that - bit of action going on.
Do try not to drown the bathroom though.
Did I mention the reason one of the reasons I am so worried about bugs at the moment?
In two weeks I'm off to Australia to stay with family. While there I will be embarking on a seven-day cruise.
It began with a phone call from daughter number two. "Hi mum - do you want to come on a cruise with us?"
Um, when and where? To cut a long story short she said "I'll pay - I have to book two cabins anyway."
Uh-oh, I thought - that means I'll be sleeping in a cabin with three children.
I admit I hesitated but then I thought why not, about time I had a bit of an adventure.
However, people love to tell me horror stories when I mention I'm going on a cruise.
"Oh, I heard about one cruise where more than 200 passengers came down with a gastro bug."
Imagine that - but, no, I'm not going to think the worst. I'm going to have a darned good time - and look out anyone I see not washing their hands.
• Linda Hall is assistant editor of Hawke's Bay Today.
