UK tabloid newspaper the Daily Mail was the first to report the story, and other news outlets repeated the information. All quoted a study led by a Swiss doctor, Dr Andreas Gutzeit.
Reports from published research
The study does exist, and was indeed headed by Prof Andreas Gutzeit of the Institute for Radiology and Nuclear Medicine at Klinik St Anna in Lucerne, Switzerland.
The results were published in the journal European Radiology, in the article “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”.
Men are dirtier than dogs — but that wasn’t point of study
The research examined only 18 bearded men, and 30 dogs.
The men did have more bacteria in their beards than was found in the dogs’ fur. But the study’s main purpose was to find out whether it would be safe to have dogs and humans use the same MRI scanner.
“One of the main reasons for the scepticism of dogs sharing the same MRI scanners as humans is the legitimate concern of hygiene,” the study says.
“People are afraid that they will contract zoonosis if they share scanners with their furry friends.”
Zoonosis, or a zoonotic disease, is any sickness that can spread from animals to people.
The study found there was a much higher “bacterial load” of human-pathogenic microorganisms in specimens taken from men’s beards than those from dogs’ fur.
All 18 of the men showed high microorganism counts, but only 23 of the 30 dogs had high microorganism counts and seven had moderate microorganism counts.
Study limited by size and bias
The researchers emphasise that the results did not mean that all bearded men carry more bacteria than all dogs, or that there’s less bacteria in the fur of all dogs than there is in all men’s beards.
Only a small number of people – and dogs – were sampled.
The study does say “dogs can be considered as ‘clean’ compared with bearded men”. But it adds that this is only based on the study’s limited findings.
The researchers also admit there is a gender bias as no women were included in the study.
“There is no reason to believe that women may harbour less bacteriological load than bearded men.” – Taryn Willows
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