Oct 11, 2024 20:00:00

Large amounts of 'unknown viruses' discovered in household toothbrushes and showerheads, which could lead to the development of new antibiotics

When you think of places where 'unknown viruses' have been discovered, many people may imagine places that are difficult to reach, such as the deep sea or tropical rainforests. However, a study led by a research team at

Northwestern University found that large amounts of unknown viruses were found in everyday items such as 'used toothbrushes and showerheads.'

Frontiers | Phage communities in household-related biofilms correlate with bacterial hosts
https://www.frontiersin.org/journals/microbiomes/articles/10.3389/frmbi.2024.1396560/full

Viruses are teeing on your toothbrush, showerhead - Northwestern Now
https://news.northwestern.edu/stories/2024/10/viruses-are-teeming-on-your-toothbrush-showerhead/

Toothbrushes and showerheads are teeing with viruses unknown to science, study shows | Live Science
https://www.livescience.com/health/viruses-infections-disease/toothbrushes-and-showerheads-are-teeming-with-viruses-unknown-to-science-study-shows

The indoor microbiome is influenced by many factors, including resident behavior, hygiene, geography, and infrastructure. The research team focused on phages , which are viruses that infect and replicate in bacteria.

The study involved samples from 34 toothbrushes and 92 showerheads, and a metagenomic analysis of the viruses they contained, said study co-author Erica Hartman , an associate professor at Northwestern University who has previously investigated microbes living on toothbrushes .

'This project started out of curiosity,' says Hartman. 'We wanted to know what kind of microbes live in our homes. When you think about indoor environments, tables and walls are inhospitable places for microbes. Microbes love being in an environment with water. So where is that water? In your showerhead or toothbrush.'

The analysis revealed that the samples contained a total of 614 viruses, most of which are believed to be previously undiscovered and are phages that infect bacteria rather than humans.

'The number of viruses we've discovered is astonishing,' Hartman said. 'We've found so many we barely know about and have never seen before. It's amazing how much untapped biodiversity is all around us. It's right under our noses and we don't even have to go far to find it.'

'The showerhead and toothbrush viruses have very little overlap, and no two samples have the exact same virus,' Hartman said. 'The showerhead and the toothbrush are like little islands. This highlights the incredible diversity of viruses out there.'

While no patterns were found across samples, the researchers found that the viruses found in this study were often mycobacteriophages, which infect

mycobacteria , including those that cause diseases such as leprosy, tuberculosis and chronic lung infections, which could one day allow scientists to harness them to treat infections.

'You can imagine harvesting these mycobacteriophages and using them as a way to remove pathogens from water supplies and wastewater systems,' Hartman said. 'We want to explore all the functions these viruses might have and find ways to use them.'

Some people may be worried when they hear that 'there are many unknown viruses living on toothbrushes and shower heads,' but Hartman points out that there is no need to worry. 'Microbes are everywhere, and most of them don't make us sick. On the contrary, the more we attack them with disinfectants, the more resistance they may develop or the more difficult they may become to treat. We should all accept viruses,' he advised.