By Stephanie Stahl

PHILADELPHIA (CBS) — It’s been a particularly bad flu season, influenza and colds come from viruses that are very contagious. One school experiment showed just how easily germs are spread.

Some youngsters get a lesson in disease prevention from the experts.

Friends Juliana and Amari start the demonstration by rubbing in “Glo Germ,” a harmless lotion visible only under a black light.

The goal in 30 minutes is to see how far the germs travel and how fast when kids do what kids do.

As Juliana and Amari play, the Glo-Germ starts spreading from toy to kid and from kid to kid.

Under a black light, you can see the Glo-Germ on the knobs, on the back of a chair, the train set, on utensils. And the Glo-Germ showed up on many of the children.

There were even traces of Glo-Germ after they washed their hands.

Seeing how quickly germs can be spread among children it’s easy to understand why the average American student gets 6 to 10 colds per year. That’s in addition to outbreaks of the flu and other contagious infections.

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