Table 2 shows serotypes of non-O157 STEC isolated from animals. Some of the STEC isolated from animals are of the same serotype as human isolates and many of these have been associated with HC or HUS in humans. Sheep and goats have been found to have higher excretion rates, while pigs and chickens do not appear to be significant reservoirs of these bacteria. Bovine excretion of specific serotypes is intermittent and the causes of this are not clear. Due to intermittent excretion and to the difficulty of isolating non-O157 STEC, the true prevalence of STEC in cattle and other animals is probably higher than some studies suggest.
Information is limited for other animal species.
Non-O157 STEC associated with disease in animals belong to a limited number of serotypes, some of which have also been associated with human disease. Meat and meat products, dairy products and any foods cross-contaminated by animal products during preparation may be contaminated. Foods such as fruit and vegetables may be contaminated during growth, harvest and production. As ruminants have been identified as an important reservoir of STEC, raw meat and milk have been most frequently studied due to their potential for contamination during production. Only a limited number of other foods have been studied.