Now more than ever, many people are curious about what germs may be lurking in public spaces. Due to COVID-19, some think twice before grabbing, for example, a shopping cart’s handle before wiping it down. But is that necessary? Experimental medicine and parasite vaccinology PhD candidate Dilhan Perera has taken to TikTok to illustrate just how much bacteria is actually lying around grocery stores.
In a massively viral video that has now been viewed over 3.1 million times, the 25-year-old student swabs and tests commonly touched items for bacteria, including: apples, milk cartons, meat packages, freezer door handles, shopping cart handles, and a card reader at self-checkout.
Afterward, Dilhan stored the samples in an incubator at 37 degrees celsius for 48 hours to see what would grow.
With the help of lab equipment, the bacteria found can be viewed in individual colonies. For those who, like me, are not microbiologists, a bacterial colony is basically a group of bacteria that comes from a single mother cell. The mother cell is able to reproduce genetically identical cells, and yay, it's a whole dirty party filled with thousands of bacteria cells that present themselves as these little droplets.
"By looking at the growth of bacteria on plates, we can visualize microorganisms around us that we normally can't see," Dilhan told BuzzFeed. "Everything around us is covered in microorganisms. By counting colonies of bacteria that grow on plates, we can get an idea of how much bacteria are on certain items, as each colony arose from one individual bacterial cell. This shows us that some surfaces or products may be more contaminated or more likely to harbor bacteria than others."
Ready or not, here are the final results:
Apples: 32 Bacterial Colonies
Milk Carton: 2 Bacterial Colonies
Meat Package: Over 300 Bacterial Colonies
Freezer Door: 5 Colonies
Shopping Cart Handle: 1 Colony
Card Reader: 6 Colonies
Before you download Instacart or pack an extra pair of gloves, Dilhan wants to make it clear that his video is not meant to cause alarm. "According to the NIH, less than 1% of bacteria actually make us sick. The takeaway from this video is that bacteria are all around us and people should practice proper hygiene, especially with food."
"A lot of my videos can be fear-instilling to some, but truly my goal is just to help people be aware of the microbes that exist around us and be mindful that these germs can sometimes make us ill," Dilhan told BuzzFeed. "In addition to this, I want to demonstrate the research process to help foster trust in science. Some of my videos teach microbiology techniques used in common practice, and others illustrate those techniques in use to show how researchers design experiments to answer scientific questions."
For the most part, many in the comments were actually able to stop looking through their fingers in horror and find comfort in the store's cleanliness.
And others are already waiting for Dilhan's next in-depth look into the world of bacteria on everyday products.
You can watch Dilhan's full grocery store results video below: