It is almost an art photo and yet it is the result of a lesson that a researcher mother gave to her 8 year old son who did not want to wash his hands. After playing in the garden, Tasha Sturm asked her son to put her hand on the gel of a Petri dish, intended for the culture of bacteria.
It didn't take long before flowers bacteria colonies varied, as shown in the photo published by the researcher on the Imgur sharing platform. A striking visual experience that can only encourage you to wash your hands regularly.
This is what happens when you don't wash your hands!
In reality, this little experiment works with any everyday object placed on the gel of the Petri dish (like a cellphone if you want to scare yourself) since bacteria naturally surround us. Note also that what we see here is in fact only the proliferation of bacteria in an optimal environment, to the point of becoming visible to the naked eye. In reality, the bacteria around us are subject to multiple natural factors that prevent their excessive development.
The good news is that none of the bacterial colonies that have appeared is frankly harmful, our immune defenses being able to defend ourselves against this normal presence of these tiny neighbors of our ambient environment.