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<\/div>Our toothbrushes host huge numbers of viruses as well as bacteria<\/p>\n
Kathrin Ziegler\/Getty Images<\/p>\n<\/div>\n<\/figcaption><\/figure>\n<\/p>\n
Hundreds of viruses that infect bacteria have been found on toothbrushes and showerheads. This isn\u2019t something to be worried about, though, because the viruses aren\u2019t harmful to humans and studying how they work could reveal new ways to kill drug-resistant bacteria.<\/p>\n
It is already known that our toothbrushes and showerheads are full of bacteria<\/a> from our mouths and from water supplies. But we know little about the viruses that also dwell on these surfaces.<\/p>\n To gain a better picture, Erica Hartmann<\/a> at Northwestern University in Illinois and her colleagues swabbed 92 showerheads and 36 toothbrushes from the bathrooms of people living in the US.<\/p>\n By sequencing the DNA from the swabbed samples, the researchers discovered more than 600 viruses known to infect bacteria, called bacteriophages. Most of the viruses, which aren\u2019t harmful to humans, came from the toothbrushes, and many hadn\u2019t been described before. \u201cThat\u2019s wild, it just underscores how much novel stuff is out there,\u201d says Hartmann.<\/p>\n <\/p>\n The researchers didn\u2019t test whether the viruses are affecting the thousands of bacteria that they also found, but a bacteriophage tends to do one of two things, says Hartmann. It might hijack the molecular machinery of a bacterium to make copies of itself, and then kill the bacterium as it exits. Or it can integrate into the bacterial genome and change how bacteria behave.<\/p>\n The bacteriophages that Hartmann and her colleagues identified are probably present on any moist surface around the home, such as sinks and inside fridges. \u201cWe would absolutely expect them anywhere,\u201d she says.<\/p>\n \u201cIt\u2019s a fascinating resource that allows us to better understand the breadth and the details of phage activity inside a home,\u201d says Jack Gilbert<\/a> at the University of California, San Diego.<\/p>\n Because engineered bacteriophages can be used to kill drug-resistant bacteria when antibiotics fail, the discovery of so many new ones could point the way to more treatments, says Dirk Bockm\u00fchl<\/a> at the Rhine-Waal University of Applied Sciences in Germany.<\/p>\n Topics:<\/p>\n<\/section><\/div>\n