Rain, puddles and mud — they’re all bad news for grown-ups on their way to work. But scientists now say that dirt can be good for children! Researchers in America have found that bacteria living on the skin help cuts and grazes to heal. They studied the cells of mice and humans, and noticed that the natural bacteria stopped cuts from swelling up. “These germs are actually good for us,” said Professor Richard Gallo, who led the study at the University of California.

A bacterium is a type of germ. Germs are found all over the world in all sorts of places. Bacteria can invade people, plants and animals and can be bad for us by spreading diseases. That’s why it is important that we wash our hands, especially before eating and after going to the toilet. But some experts say that it’s good for children to be exposed to some germs because it helps to build their immune systems, the body’s natural defence against illness and disease. Scientists say that having some contact with germs can also prevent us from developing allergies to things such as pollen and pets. If children have no contact with germs, later in their lives their bodies might overreact when they come into contact with such things and it could trigger an allergic reaction.

Scientists say that allergies are increasing in the UK because people have become obsessed with cleanliness.

Some parents are so worried about their children getting ill from bacteria that they don’t let them go out to play and get dirty, and people clean their houses more than they need to.

Rates of allergy have tripled in the UK over the past ten years and one in three people now has an allergy of some sort. Of course, all this doesn’t mean that you can ban bathtime and make yourself a dirt and tomato sandwich for lunch. But according to this latest research, a little bit of muck never did anyone any harm.

Fun with dirt

• Splash in the puddles — get your wellies on and make the most of the downpour. Just remember to take them off before you run up the stairs to your room

• Climb a tree (checking that it’s safe first, of course). Rub your hands along the trunk and enjoy the view from the branches

• Use your hands to make a perfect mud pie

• Take your bike to the park the day after it has rained and race your friends, pretending that you are a cross-country cyclist

• Go treasure-hunting in your back garden and see what kind of worms and bugs you can find

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