FOX 12 investigated the spread of germs in schools and what we've found may make your skin crawl.
We teamed up with Holy Redeemer in North Portland to test several different spots in the school's K-8 classrooms.
Students identified staph, mold, fungus and other bacteria growing on surfaces kids touch every day.
"We discovered that there are bacteria everywhere," said science teacher Mari Galati. “That doesn't mean something is not being cared for, it just means bacteria exists everywhere. This would universally be true for likely any home, or school you'd walk into."
Avoiding germs in a school is nearly impossible, especially at the start of flu season.
"A sneeze in a classroom will contaminate every desk by the time the droplets are done," she added.
That bacteria is invisible to the naked eye, which is why FOX 12 asked Galati and her 8th grade science class to help expose where those germs are hiding.
The class came up with a list of random places they wanted to go out and test around the school for germs. There were things they expected to be dirty, like a toilet seat, the cafeteria floor, a water fountain drain and a bench in the boy's locker room.
Students also managed to chase down a TriMet bus that stops outside of the school and swabbed a seat and a door handle too.
Overall, the class gathered 18 different samples from around the school and let them cook in an incubator over a weekend.
On Monday, students came back to petri dishes full of bacteria. The class identified 290 different colonies growing from one swab of a TriMet bus seat, and 400 different colonies of bacteria growing on a sample of the hallway carpet.
But, that's nothing compared to what was lurking in the water fountain drain. The class found 1,600 different colonies of bacteria growing on that sample and more than 2,000 colonies mounting on their sample of the cafeteria floor.
Results, that certainly make you think twice about the "five-second rule."
In a twist, the cleanest spot in the whole school was the cafeteria door handle. Students found no bacteria growing on it all, potentially because it had just been cleaned.
"Most of what we've found is because we touch things," said Galati. "Human beings are covered in single celled critters, so we would expect to find these results. It's important to be aware before you're eating or putting anything near your face, or mouth."
In a school where kids share practically everything, the spread of germs is inevitable. Which is why Galati also keeps vats of hand sanitizer on tap as a defense.
"If you use Purell going in and out of a classroom every time, I heard you can drop absenteeism by 25 percent,” Galati said.
Here's the full list of the classroom's results: Kindergarten carpet - 101 colonies Little girls' toilet seat - 6 colonies Bathroom door handle - 1 colony Kindergarten desk top - 40 colonies Tech lab keyboard - 10 colonies Cafeteria floor - >2,000 colonies Hall carpet - 400 colonies 8th grade desk top - 5 colonies Locker room bench - 45 colonies BTC toy - 1 colony Inside of water bottle - 160 colonies 8th grader's hand - 96 colonies Cell phone - 55 colonies Lunch box handle - 13 colonies Hand sanitizer pump - 8 colonies Water fountain drain - >1,600 colonies Cafeteria door handle - 0 colonies Teacher's fridge - 200 colonies Bus door handle - 8 colonies TriMet Bus seat - 290 coloniesThe CDC says if possible it's best to stay home from work, school and errands when you are sick, to prevent spreading your illness to others.
Cover your nose and mouth when sneezing, or coughing. Washing your hands often will also help protect you from germs this flu season.
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