Which harbour more germs – touch screens or keyboards?

‘QWERTY tummy' is probably as bad as it sounds.


Asked by: Rosie O'Brien, Durham

It’s been dubbed ‘QWERTY tummy’. Yes, the bad news is that one of the most widespread bugs found on computer keyboards is Staphylococcus aureus, a bacterium that causes food poisoning. That and other harmful germs are transferred onto our keyboards after we have been to the loo, eaten lunch at our desk or picked our nose.

A study in 2008 found that some keyboards were dirtier than a toilet seat. The news is no better when it comes to the screens on our phones. Two years ago, a study from the London School of Hygiene & Tropical Medicine and Queen Mary University of London, found that 92 per cent of phones harboured bacteria despite 95 per cent of users saying they washed their hands thoroughly. One in six handsets were contaminated with Escherichia coli bacteria, the type that leads to severe food poisoning.

Whether touch screens are grubbier than keyboards or vice versa is tricky to determine. Given that we tend to take our phones and tablets everywhere, sometimes even to the loo, I would say that touching transfers more toxins than typing. A pack of anti-bacterial hand wipes should do the trick.

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