David Dowling, a research fellow in paediatrics, at Childrens Hospital Boston, agrees. "The hypothesis of hygiene, as put forward in the late 1980’s, had a subtle but fatal flaw: it did not contemplate the fact that, while exposure to some microbial organisms may be bad and leads to infection, exposure to other microbial organisms in our environment may be beneficial in ways yet to be understood," he says. "In short, it all boils down to the idea of maximising appropriate exposure. But there is little evidence that appropriate exposure includes the need for pathogenic infection."
What’s needed are strategies to boost our exposure to beneficial microbes, whilst at the same time reducing our exposure to the ones that cause disease. But embracing dirt and failing to wash our hands is not the answer. Indeed, infectious intestinal diseases such as campylobacter are currently 43% percent higher than they were in the 1990s. Antibiotic resistance is also on the increase, while an ageing population means more people are susceptible to infectious illness.
Targeted hygiene is one solution. “It means you can be as tidy or dirty as you like in your day-to-day activities, but you need to make sure you are hygienically clean at the times and the places that matter,” says Bloomfield. These include immediately cleaning hands and kitchen surfaces that have come into contact with raw meat (particularly chicken); covering your hands and mouth (or using a tissue), if you cough or sneeze - and then washing your hands and disposing of the tissue; not only washing your hands after visiting the bathroom, but regularly disinfecting the toilet seat, flush, taps and bathroom handles.
At the same time, the panel recommends a number of measures to boost exposure to beneficial microbes, particularly during early childhood. “Data are now strong enough to encourage changes such as encouraging natural childbirth, physical interaction between siblings and non-siblings, more sport and other outdoor activities (including babies in prams) and less time spent indoors, and reduced antibiotic consumption,” they write.
Our diet is also looking increasingly important, adds Rook. “Fibre and polyphenols (present in red wine and fruit and vegetables) seem to help maintain the diversity of our gut microbiota, whereas if we take diets deficient in these things, diversity decreases, and some important species become extinct,” he says.
The bugs living upon and within us are part of the rich tapestry that makes us human. It seems we really are stronger together.
Linda Geddes is a freelance writer in Bristol and the author of Bumpology: The Myth-busting Pregnancy Book for Curious Parents-to-be.
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