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Step aside tropical rainforests and coral reefs—the latest hotspot to offer awe-inspiring biodiversity lies no further than your bathroom.

In a new Northwestern University-led study, microbiologists found that showerheads and toothbrushes are teeming with an extremely diverse collection of viruses—most of which have never been seen before.

Although this might sound ominous, the good news is these viruses don't target people. They target bacteria.

The microorganisms collected in the study are bacteriophage, or "phage," a type of virus that infects and replicates inside of bacteria. Although researchers know little about them, phages have recently garnered attention for their potential use in treating antibiotic-resistant bacterial infections. And the previously unknown viruses lurking in our bathrooms could become a treasure trove of materials for exploring those applications.

The study, "Phage communities in household-related biofilms correlate with bacterial hosts but do not associate with other environmental factors," was published Wednesday (Oct. 9) in the journal Frontiers in Microbiomes.

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