Men's beards harbor more germs than dog fur

man stroing beard
© g-stockstudio

When it comes to potentially infectious microbes, beards beat the dogs.

First things first. Why is this on TreeHugger? Because A) bacteria are fascinating and play a huge role in the nature of us and our planet B) avoiding potentially-infectious germs is good preventative medicine; and mostly C) after writing too much about the imminent collapse of nature thanks to humankind, sometimes a writer just wants to write about beards and dogs.

So here we are; and mind you, this is interesting.

A group of 13 researchers had a question, as described in the study's objective: "To determine whether it would be hygienic to evaluate dogs and humans in the same MRI scanner."

Well that's the short version, at least. The title of the study, which was published in European Radiology, gives a bit more detail: "Would it be safe to have a dog in the MRI scanner before your own examination? A multicenter study to establish hygiene facts related to dogs and men"

(Which now ranks amongst my top favorite scientific study titles.)

Anyway, the whole thing came about because the cost of MRI scanners is prohibitive for most veterinary clinics to have on site, so a number of dog MRIs were to be conducted at the radiology department of a European hospital that also does around 8,000 MRI scans of humans each year, explains Brandon Specktor at LiveScience.

For the study, they took samples from 30 dogs – samples came from saliva swabs as well as fur from the dogs' backs, an area that is prone to skin infections and is "particularly unhygienic." The dogs were scanned, and then the researchers took samples from the scanner itself.

Next, they collected samples from the beards of 18 hospital patients; the men ranged in age from 18 to 76, and were in relatively good health. After their MRIs, samples were taken from the scanner again.

Here's what they found, as noted in the study:

  • A significantly higher bacterial load in specimens taken from men’s beards compared with dogs’ fur.
  • All of the men (18 out of 18) showed high microbial counts, whereas only 23 out of the 30 dogs had high microbial counts.
  • Human-pathogenic microorganisms were more frequently found in human beards (7 out of 18) than in dog fur (4 out of 30).
  • More microbes were found in human oral cavities than in dog oral cavities.
  • After MRI of dogs, routine scanner disinfection was undertaken and the CFU [colony-forming units] found in specimens isolated from the MRI scanning table and receiver coils showed significantly lower bacteria count compared with “human” MRI scanners.

As Specktor reports, "Seven of the men and four of the dogs tested positive for human-pathogenic microbes – the kind of bacteria that can make a person ill if they colonize the wrong part of the host's body. These microbes included Enterococcus faecalis, a common gut bacteria that is known to cause infections (especially urinary tract infections) in humans, and several cases of Staphylococcus aureus, a common skin/mucous-colonizing bacteria that may live on up to 50% of all human adults, but can cause serious infections if it enters the bloodstream."

The authors concluded that, "bearded men harbour significantly higher burden of microbes and more human-pathogenic strains than dogs." But that said – before the beardless among us start feeling all high and mighty – this was a very small study. And, the authors added, "there is no reason to believe that women may harbor less bacteriological load than bearded men."

So maybe in the end this isn't about beards at all ... and really, the focus should be directed at one of the study's key points: "Deficits in hospital hygiene are a relevant risk for patients."

With deadly healthcare-related infections on the precipitous rise (and antibiotic efficacy on the wane), this is no small matter. And given that "antibiotic resistance is one of the biggest threats to global health, food security, and development today," according to the World Health Organization, it seems prudent to be keeping tabs on the microbes – especially in hospitals where they revel in running amok.

"The central question should perhaps not be whether we should allow dogs to undergo imaging in our hospitals," the authors write, "but rather we should focus on the knowledge and perception of hygiene and understand what poses real danger and risk to our patients."

Wait, this was supposed to a fun story, what happened? Next stop, cute kittens.

Men's beards harbor more germs than dog fur
When it comes to potentially infectious microbes, beards beat the dogs.

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