An old photo of an 8-year-old's handprint is bubbling back up on the internet, and "bubbling" is probably a gross understatement.

The photo was first shared by mom Tasha Sturm, and it isn't of her son's hand in acrylic paint or pushed into clay. Nope, instead it's all the bacteria that grew on the then-grade-schooler's hand while playing outside before he pressed it onto a large Petri dish.

Tasha, who had worked as a microbiology lab tech in California, told NBC in 2015 [1] that she was used to swabbing cell phones and door knobs for germs as part of basic experiments with her kids, but one day she decided to go straight to the source.

That Spring, she asked her son to play outside and pet the family dog, and when he came back inside, she had him place his hand onto the sterile dish, which was filled with a substance used to grow bacteria. She then incubated the dish at body temperature for a day and let it sit out at room temperature.

Once the bacteria had been growing for a week, she took the photo, which is going viral all over again this week. If the results make you want to lunge for the hand sanitizer, you're not alone.

In fact, the white spots are likely staph (or Staphylococcus), the yellow and orange spots might be yeast, and the large white circle in the bottom right of the image is likely Bacillus, which is commonly found in soil.

Still, Tasha said that it was all normal things humans are exposed to daily. "The skin protects us from a lot of the bad stuff out there," she said. "The take-home message is that to have a healthy immune system, you've got to be exposed to stuff."

But it doesn't hurt to wash your hands every now and then, either!