Table 2.

Overall distribution of ehxA, espP,eae, stx1, andstx2 in STEC isolates from serotypes which are reportedly not found in humans, from serotypes found in humans, and from serotypes clearly associated with severe disease in humans (set 1)

GeneDistributiona in serotypes:
TotalNot from humansFrom humansFrom severe disease
ehxA146 (61.6)59 (60.2)87 (62.6; 0.7100)64 (71.9; 0.0114)
espP148 (62.4)60 (61.2)88 (63.3; 0.7441)55 (61.8; 0.8728)
eae77 (32.5)23 (23.5)54 (38.8; 0.0128)43 (48.3; 0.0001)
stx1148 (62.4)72 (73.5)76 (54.7; 0.0033)46 (53.9; 0.0358)
stx2134 (56.5)42 (42.9)92 (66.2; 0.0004)63 (70.8; 0.0006)
No. of isolates237 98 139 89 
No. of serotypes118 53 65 39 
  • a Of the total 237 isolates of set 1, 159 were of animal origin, 18 were of food origin, and 60 were of human origin. The numbers in the columns represent numbers of isolates. The first number in parentheses indicates the percentage of the total category positive for the respective characteristic. The second number in parentheses for the fourth column indicates the P value for chi-square tests comparing isolates from serotypes found in humans with those not found in humans. The second number in parentheses in the last column indicates the P value for chi-square tests comparing isolates from serotypes associated with severe disease to all the others.