Shiga toxin-producing Escherichia coli (STEC), also known as Vero cytotoxin-producing Escherichia coli (VTEC), are a group of bacteria that cause infectious gastroenteritis. The most frequently reported STEC strain to cause illness in England and Wales is E. coli O157.
STEC infection is a relatively rare cause of gastrointestinal illness in England, with around 800 cases diagnosed annually. Symptoms can range from mild gastroenteritis through to severe bloody diarrhoea.
On rare occasions, STEC infection can cause 2 serious conditions:
haemolytic uraemic syndrome (HUS)
thrombotic thrombocytopaenic purpura (TTP)
Both conditions affect the blood, kidneys and, in the most severe cases, the central nervous system.
The main reservoir for STEC is cattle and other ruminants. Transmission to humans occurs through:
consumption of contaminated food or water
exposure to a contaminated environment involving direct or indirect contact with animals or their faeces
The low infectious dose of STEC means that once in the population, person-to-person spread is common.