600 viruses found on showerheads, toothbrushes in new study

You may need a shower after hearing the results of this eye-opening study.

Northwestern University researchers identified more than 600 different viruses on 92 showerhead and 34 toothbrush samples — and no two samples were alike.

“The number of viruses that we found is absolutely wild,” said indoor microbiologist Erica M. Hartmann, who led the study. “We found many viruses that we know very little about and many others that we have never seen before.”

The good news is that the microbial agents detected on the showerheads and toothbrushes are bacteriophages, viruses that infect and kill bacteria.

The researchers noted that mycobacteriophages were most abundant. These viruses infect mycobacteria, a type of bacteria that causes diseases like tuberculosis, leprosy and certain chronic lung infections.

“We could envision taking these mycobacteriophage and using them as a way to clean pathogens out of your plumbing system,” Hartmann explained. “We want to look at all the functions these viruses might have and figure out how we can use them.”

The study, published Wednesday in the journal Frontiers in Microbiomes, is a follow-up to research from Hartmann that found that the overwhelming majority of microbes on your toothbrush probably come from your mouth, not from a flushing toilet creating a plume of aerosol particles.

The toothbrush study was affectionately dubbed “Operation Pottymouth.”

“This project started as a curiosity,” Hartmann said. “We wanted to know what microbes are living in our homes. If you think about indoor environments, surfaces like tables and walls are really difficult for microbes to live on. Microbes prefer environments with water. And where is there water? Inside our showerheads and on our toothbrushes.”

Hartmann recommends washing showerheads with soap and water or soaking them in vinegar to remove calcium buildup. She also suggests regularly replacing electric toothbrush heads.

Hartmann is not a fan of antimicrobial toothbrushes, which she said can lead to antibiotic-resistant bugs.

“Microbes are everywhere, and the vast majority of them will not make us sick,” she shared. “The more you attack them with disinfectants, the more they are likely to develop resistance or become more difficult to treat. We should all just embrace them.”

How to sanitize your toothbrush

Southern California dentist Dr. Joyce Kahng recommends changing your toothbrush every three months and not sharing it with anyone.

Last week, she suggested 10 ways to sanitize the bristles.

• Wash it with hand soap
• Dip it in boiling water for 30 seconds
• Dip it in mouthwash for two minutes
• Leave it in hydrogen peroxide overnight
• Dip it in white vinegar for 30 seconds
• Use a mixture of 2 teaspoons of baking soda and water
• Use a mixture of 2 cups of water and 2 teaspoons of bleach for six minutes
• Dip it into a half of a denture tablet mixture for 90 seconds
• Dip it in hypochlorous acid
• Use a UV sterilizer