TABLE 3.
Serogroups and virulence genes of E. coli strains (strain set 2) recovered from edema disease outbreaks and submitted to the Iowa State University Veterinary Diagnostic Laboratory between 1996 and 2000
| Virotype | No. of strains positive in serogroup:
|
|||||
|---|---|---|---|---|---|---|
| O138 | O139 | O141 | O147 | NTa | Total (%) | |
| f18 sta stb stx2 | 5 | 1 | 5 | 9 | 4 | 24 (43) |
| f18 stb stx2 | 1 | 0 | 3 | 5 | 1 | 10 (18) |
| f18 stx2 | 0 | 1 | 1 | 8 | 1 | 11 (20) |
| stx2 | 0 | 1 | 1 | 1 | 4 | 7 (13) |
| sta stb stx2 | 0 | 1 | 0 | 0 | 0 | 1 (2) |
| sta stx2 | 1 | 0 | 0 | 0 | 0 | 1 (2) |
| stb stx2 | 0 | 1 | 0 | 0 | 0 | 1 (2) |
| Total (%) | 7 (13) | 5 (9) | 10 (18) | 23 (42) | 10 (18) | 55 (100) |
a
NT, nontypeable strains. These isolates either autoagglutinated with O138, O139, O141, or O147 sera or did not agglutinate with any of the sera.