Viral content: Why the Food Standards Agency is watching what you tweet
Have you ever seen anyone tweeting overly detailed symptoms and found yourself thinking “ugh, nobody needs to know that”? Apparently you, I and all human decency were wrong: since 2013, tweeting your symptoms has been doing a huge service to the UK Food Standards Agency (FSA), who use the information to keep an eye out for incoming national outbreaks of norovirus.
Norovirus is highly contagious, and spreads via food and person-to-person contact, so if a lot of people suddenly tweet similar symptoms in a specific British region, the agency knows to investigate further. Despite (presumably) plenty of people keeping their illnesses to themselves, the hit rate is really good, with Dr Sian Thomas, the FSA’s head of information management telling the BBC that “between 70-80% of the time, we are able to accurately predict an increase the next week.”
“There’s a really good correlation between the number of mentions on Twitter of ‘sick’ and a range of search terms, with the incidents of illness as defined by laboratory reports.”
Originally, the FSA tested the waters by studying Google searchterms, but found the immediacy of the data more useful with social media. The result is a model that scans tweets for keywords and phrases that link to symptoms of norovirus, while excluding results which imply pregnancy, anxiety or boozing – something that Dr Thomas concedes makes analysis “more tricky towards Christmas.”
If the analysis detects three consecutive weeks’ worth of increases, the FSA triggers a digital public awareness program advising the public on how to avoid becoming part of their study. Simple stuff, apparently – like washing your hands and avoiding other people while you’re sick, until the virus is out of your system. It’s not a full-blown intervention, but these small nudges could make all the difference when trying to keep an outbreak under control.
It’s certainly a creative way of using social location data to tackle a health problem – and it’s good to know that people tweeting their symptoms are inadvertently doing a public service in their search for sympathy.