Characterization of Shiga Toxigenic Escherichia coli O157 and Non-O157 Isolates from Ruminant Feces in Malaysia
Table 4
Occurrence of target virulence factors and “big 6” non-O157 serogroups in the initial PCR screen of the enriched samples from each farm (A–F).
Farm
Number of samples tested
Percent positive for virulence gene combinationsa
Percent positive for serogroupsa
, , eaeA, ehxA
, , ehxA
or , eaeA, ehxA
, ehxA
, ehxA
eaeA, ehxA
eaeA
or alone
O111
O26
O121
O145
O45
O103
A
25
6.6
2.9
0
0
1.5
0
0
0
0
0
5.9
0
3.7
5.1
B
44
13.2
2.9
0
0
0
0
0
0
0.7
9.6
13.2
0
2.2
16.2
C
9
2.9
0
0
0
0.7
2.2
0.7
0
0
2.9
0.7
1.5
3.7
5.1
D
24
1.5
4.4
1.5
0
0
0.7
0
2.9
0
8.1
0
0.7
0.7
10.3
E
18
5.9
2.9
0.7
0
0
0
0
0
3.7
4.4
0.7
0.7
8.1
7.4
F
16
0
2.2
0
1.5
0
0
0
0
0
0
0
0
0
0
Total
136
30.1
15.4
2.2
1.5
2.2
2.9
0.7
2.9
4.4
25
20.6
2.9
18.4
44.1
The percentage of samples positive were calculated by dividing the number of positive samples for each category in the initial PCR screen by the total number of samples () collected.
