An outbreak of E. coli O157 has been linked to burgers in Glasgow, apparently after a Top Gear Live event at the Hydro.

There are many strains of Escherichia coli and almost all are completely harmless – it is one of the most common of our normal gut flora. But some strains are really nasty; Shiga toxin-producing E. coli (STEC) – the most common of which is E. coli O157:H7 – causes serious foodborne intoxication and the toxins it produces are heat-stable and so not denatured by cooking. The toxin is heat-stable up 100°C.

One of the reasons this strain is particularly dangerous is you only need between 10 and 100 organisms to cause infection – compared with over 1,000,000 required for other pathogenic E. coli strains. (There are 5 principal types of E. coli that cause diarrhoeal diseases that I won’t bore you with).

E. coli O157 food poisoning is a notifiable illness (so the doctor is legally obliged to inform Environmental Health so they can investigate the cause). Recent outbreaks in the UK include one associated with a children’s farm in Surrey (ungulates are known carriers) as well as outbreaks associated with poor hygiene in butchers – including the tragic outbreak in South Wales that was the subject of the Pennington Report. The Food Standards Agency made significant changes to food law enforcement in 2011 in the wake of Prof Pennington’s recommendations and further guidance – I’m currently wading through  the third draft – is imminent.