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Viral Science Experiment Shows Importance of Hand-Washing and Flu Shots

EDITOR’S NOTE: (Oct. 9, 2017, 11:26 a.m. ET): A previous version of this story credited the experiment to Donna Gill Allen and Marvilyn Lyons based on a Facebook post and conversation with Allen. However, a 2014 post by Courtney Lee Simpson has since surfaced, and the post by Allen has been removed. NBC4 reached out to Donna Gill Allen, who clarified that she initially believed the experiment belonged to Lyons and only reposted it.


A Facebook post that used three slices of bread to teach students the importance of hand-washing went viral last month after concerned parents and teachers shared it close to 75,000 times.

The post, published by a teacher in North Carolina, went viral in late September. But a post from 2014 -- featuring the same photo and text -- shows the experiment has been around for much longer.

Courtney Lee Simpson, a preschool teacher in Oak Ridge, Tennessee, said she first conducted the experiment with her pre-kindergarten students in November of 2014. Simpson said she used gloves to put one piece of bread in a sandwich bag to be the controlled model, and then washed her hands before placing a second piece of bread in its own bag.

She then had all of her students touch the third piece of bread with dirty hands before putting it in its bag. It was not specified how long the bread slices sat in the bags, but at the end of the experiment, the picture on Simpson’s Facebook page showed the slice handled by dirty hands covered in mold, while the other two pieces looked fresh.

Simpson’s post has been shared over 300,000 times.

The viral Facebook post is a timely reminder of the danger of germs, considering flu season is just around the corner.

People are susceptible to the flu year-round, but seasonal flu activity typically picks up between October and May, the Centers of Disease Control and Prevention says.

Getting a flu vaccination is the single most effective method of preventing the flu, but the CDC also notes that good health habits like washing hands frequently and covering coughs can be helpful.

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