The bathroom equipment with unexpected bacteria

According to a new report published in Frontiers in Microbiomes last week, toothbrushes and showerheads are home to an extremely diverse mix of viruses.^[] 

“While these findings might sound concerning, it's important to understand that most of these germs don't pose a threat to human health and are simply part of everyday life,” Hannah Kopelman, DO, a dermatologist at DermOnDemand, tells MDLinx.

What's the threat to human life?

The researchers tested people’s used toothbrushes and swabs with samples from their showerheads.^[] They found over 600 different viruses, many of which have never been detected before by scientists. 

The viruses varied greatly, from person to person and item to item. “The bacteria living on the toothbrushes were microbes that commonly live in the human mouth. The microbes living in the showerhead are likely influenced by the source water and the plumbing,” says Leigh Smith, MD, an associate hospital epidemiologist and infectious disease clinician at the University of Maryland Medical Center in Baltimore, MD.

The most interesting finding, perhaps, was that most of the viruses weren’t pathogenic—at least to humans. While many viruses cause illness and infections in humans, most of the bugs detected in the study were bacteriophages—a type of virus that specifically targets bacteria rather than humans. 

What does this mean, exactly? These viruses pose no threat to humans, and may very well keep us healthy by clearing out harmful germs that cause diseases like leprosy, tuberculosis, and chronic lung infections.^[]“Bacteriophages can regulate the population of bacteria present and can have an influence on the microbial community without harming humans, which in turn could have positive health and environment[al] implications,” explains Shanina Knighton, PhD, RN, CIC, an infection preventionist and assistant research professor at Case Western Reserve University. 

The researchers also suspect that bacteriophages could be used as treatment for multidrug-resistant infections that are difficult to treat with existing antibiotics, Dr. Smith notes. But more research is needed to better understand the role that bacteriophages could play in public health. 

Here's what's growing in showerheads

Microbes thrive in moist environments such as showerheads and toothbrushes, so it’s no wonder these items are teeming with them.^[] “Bathrooms are warm, humid environments [that] create ideal conditions for microbes to thrive on surfaces like toothbrushes and showerheads,” Dr. Kopelman says. Furthermore, toothbrushes are constantly in our mouths, which naturally house tons of bacteria and viruses, Dr. Smith adds. 

If your patients are worried about the microbes festering in their bathrooms, let them know that we’re constantly surrounded by bugs. They’re in the water, air, and soil—and millions are in our bodies, according to the National Institutes of Health.^[] “Most of these microbes are harmless, and our immune systems are equipped to handle this constant exposure,” Dr. Kopelman says. In fact, she adds, being exposed to some germs helps our immune systems stay strong and responsive.