There’s a whole range of biodiversity hiding in your home right now. Shower heads and toothbrushes are chock full of viruses so varied that many of them have never been seen before. However, you don’t need to worry or stop bathing and brushing your teeth. These viruses are not coming after us. Instead, they prey on bacteria and can help us fight antibiotic resistance. The findings are described in a study published Oct. 9 in the journal Boundaries in microbiomes.
What are ‘phage’?
The microorganisms in this study are bacteriophage or ‘phage’ for short. These viruses infect and replicate in bacteria. They are among the most common organisms in nature and can even effectively fight and destroy bacteria that are resistant to many drugs. Biologists have been investigating phages for use in life-threatening antibiotic-resistant bacterial infections.
[Related: Virus observed sucking on another virus’ ‘neck’ for the first time.]
“The ‘next frontier’ of microbiology is phage,” says co-author and Northwestern University environmental microbiologist Erica M. Hartmann. Popular science. “There is a lot of interest in using phages for biotechnology or medical applications. Penicillin comes from moldy bread. It could be that the next great antibiotic will be based on something that grew on your toothbrush.”
Operation Pottymouth 2.0
The new study is an offshoot of previous research called Operation Pottymouth. Hartmann and colleagues at the University of Colorado Boulder characterized all the bacteria living on toothbrushes and showerheads to see how many microbes and bacteria from toilets ended up on toothbrushes and showerheads.
“We did a pilot study in which people sent in their used toothbrushes and we looked at which bacteria we found on them. Reassuringly, it appears that most of the bacteria on your toothbrush comes from your mouth,” says Hartmann. “For the current study, we were able to use that same data – along with data from another showerhead study – to look not at bacteria, but at their viruses.”
After characterizing the bacteria from the toothbrushes and showerheads, the team used DNA sequencing to study the viruses living on those same samples. In total, the samples contained more than 600 different viruses and no two virus samples were the same. They saw very little overlap between the virus types on both showerheads and toothbrushes, and no overlap at all between two samples.
“Toothbrushes and showerheads contain phages unlike anything we’ve seen before. Not only did we find different phages on toothbrushes and showerheads, we also found different phages on each toothbrush and showerhead,” says Hartman. “This diversity is enormous, and it is not due to anything specific to toothbrushes or shower heads. There are just so many phages waiting to be discovered.”
They also noticed more mycobacteriophages than other types of phages. These are known to infect mycobacteria, a pathogenic species that causes leprosy, tuberculosis and chronic lung infections, among other diseases. According to Hartmann, researchers could use mycobacteriophage to treat these infections, among other things.
[Related: In 1928, the discovery of ‘mold juice’ would go on to save 500 million lives.]
Why you don’t have to panic
In reality, microbes are everywhere, and most of them won’t make us sick. It is also true that the more often they are attacked with disinfectants, the more likely they are to develop resistance or become more difficult to treat.
Hartmann recommends soaking the shower heads in vinegar or regular soap and water instead of bleach to clean them and remove limescale buildup. Regularly replacing toothbrushes or brush heads is also important for good oral hygiene. Hartmann also warns against antimicrobial toothbrushes, which can lead to antibiotic-resistant bugs.
“It’s very important to work with the microbes, and not against them, so that we don’t create worse problems for ourselves, like superbugs,” says Hartmann. “By staying curious and really learning about the microbes that surround us, we will be able to make better decisions about things like the way we design and maintain our shower heads and toothbrushes – and potentially make some revolutionary new discoveries in the process.”
