WATCH: See how quickly flu germs spread in a classroom

Transcript for See how quickly flu germs spread in a classroom

As we hit the peak of flu season, look at this map. The CDC says up to 7 million people have caught the flu in season. T.J. Holmes went to a school to see how easily germs can spread. Good morning, T.J. Reporter: Some hospitals have said, hey, kids, unless you’re a patient here, don’t show up. They have banned kids from hospitals. Kids in particular, schools, prime places for the spread of germs. Kids are little petri dishes. You have heard it. It’s something else when you actually see it. Oh! The lips? You see those bright spots? Those could be germed. They’re all over these kids. You have it all in your hair. Remember the genre we talked about yesterday. Reporter: A few hours earlier, not a trace. “Gma” teamed up with miss shaftsma’s class at Chicago Christian school to demonstrate. We use a harmless powder called glo germ. Who is first? We pulled two students out of class. Oh, yeah, see. We do that. Look what happens? It come on me. That’s how germs spread. We follow the students’ every move. We see Aiden touch the water fountain. The fountain, of course, a popular spot for students. Up to 2.7 million bacteria per square inch are on the spigot. It has more than 800 times the amount found on a toilet seat. It’s now ground zero for the spread of the powder. Once in the classroom, Aiden and Mckenzie use this pen that every single kid in class touches. After an hour, I head into the classroom while the kids are at recess to check for signs of the glo germ. I feel like a crime scene investigator. The pen is covered in powder. The students move on to the library. We reapply the glo germ. The kids go the music. And then back to the classroom. Where they don’t know what’s coming. Hello, everybody. My name is T.J. Holmes. And I am a correspondent with a show called “Good morning America.” We check the students. Oh, my goodness! 8 of the 26 students in the class not including Aiden and Mckenzie have several spots on their hands an faces. Your ears! Reporter: And on their desks and chairs. Ohhings my good ps. Reporter: Hard place to keep clean. The wet wipes, disgusting. Reporter: Now the kids tell us they’re going to be more careful. Wash more thoroughly. Make sure you’re not touching anyone. Reporter: I’m not touching hands, man. It’s nasty. All right. These th is a typical school. The reminders. Always wash your hands. Soap and water preferable. Use the sanitizer. Sneeze into the arm. Remember to what sh the hands before lunch. That’s key. The kids, send them to school with a water bottle so they don’t have the use the fountain at school. Good reminders. Again, my 6-year-old. I said to her one day, why are you so dirty. She looked me in the eye. I’m a child. Some of this, we’re kids. We’re nasty. And some of it, that’s why you get the flu vaccine. You can still get it. It can mitigate. Kids are just nasty sometimes. There you go. Ugh. Coming up, what lady ga go and Glenn close did when they

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source: abcnews.go.com