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<\/div>Withdrawn and anxious, the mice in John Cryan\u2019s lab were behaving like you or I might if we had experienced workplace bullying and thought we might encounter the bully again.<\/p>\n
The good news, believe it or not, was that some of these rodents were also being fed a slurry of microbes derived from their own faeces. Unpalatable as this sounds, it had a surprisingly positive effect on their behaviour. \u201cIt was phenomenal,\u201d says Cryan, a neurobiologist at University College Cork in Ireland. \u201cWe found that these stress-induced changes in behaviour normalised \u2013 they started to behave just like normal animals.\u201d<\/p>\n
Even more surprising, this mental transformation wasn\u2019t brought about by changing the bacteria in their guts, but by tinkering with another crucial facet of the microbiome<\/a> whose importance is only now being recognised: viruses.<\/p>\n It turns out that we are riddled with these. Not the ones that make us unwell, but trillions of stowaways that play a crucial role in cultivating a beneficial microbiome<\/a> and making us healthier in turn. Recent research shows that the influence of this \u201cvirome\u201d can be found across the body, from the blood to the brain. The hope is that by tweaking it, we could find new ways of treating various ailments, from inflammatory bowel disease and obesity to anxiety<\/a>.<\/p>\n The past decade has seen a surge of interest in the microbiome \u2013 all the really tiny things that live on and in us \u2013 but this has largely focused on bacteria. The assumption until recently was that\u2026<\/p>\n<\/p><\/div>\nMicrobiome diversity<\/h2>\n