Table 3.

Characteristics of sausage outbreak-related cases

^aThe 30 cases lived in 17 households. Association to the sausage-related outbreak was obtained by presence of the implicated E. coli O157:H7 smi-H₂₁ bacterial strain in a faecal sample or ingestion of the sausage and household proximity or more than one of these parameters. Of the total 30 cases 14 had a microbiological connection (faecal smi-H₂₁ isolation) to the sausage outbreak.

^bThe smi-H₂₂ strain was not isolated from the sausage but was found in faecal isolates (n=3) from one household (with four out of five symptomatic family members) in which the sausage was consumed.

^cAnalyses by ELISA for O157 lipopolysaccharide and EspB antibodies.

^dSausage was consumed in 15 out of 17 households with infected individuals and the smi-H₂₁ strain isolated from sausage obtained from two of these households.

^eFaecal samples were PCR positive in 17 cases. PCR was negative (n=9) or lacking (n=4) in 13 cases but three of these cases had a positive serology.

^fAll of these cases had HUS and had consumed the sausage.

^gThese four individuals did not consume the sausage but were associated with the outbreak by faecal samples positive for the smi-H₂₁ strain (n=3) or smi-H₂₂ (n=1).