Volume 20, Number 12—December 2014
Research
Geographic Divergence of Bovine and Human Shiga Toxin–Producing Escherichia coli O157:H7 Genotypes, New Zealand1
Table 2
Frequency distribution of predominant SBI genotypes of Shiga toxin–producing Escherichia coli O157:H7 isolates obtained from humans, bovine fecal samples, and bovine meat samples, New Zealand, 2008–2011*
Isolate type, SBI type | No. with SBI type/no. total (%) |
p value† | |
---|---|---|---|
North Island | South Island | ||
Human | |||
AY2a | 175/278 (62.9) | 35/85 (41.2) | <0.001 |
WY12a | 41/278 (14.7) | 9/85 (10.6) | |
ASY2c/SY2c | 49/278 (17.6) | 35/85 (41.2) | |
Other |
13/278 (4.7) |
6/85 (7.1) |
|
Bovine fecal | |||
AY2a | 22/32 (68.8) | 0/8 | <0.001 |
WY12a | 6/32 (18.8) | 0/8 | |
ASY2c/SY2c |
1/32 (3.1) |
8/8 (100.0) |
|
Bovine meat | |||
AY2a-like | 137/201 (68.2) | 15/34 (44.1) | <0.001 |
WY12a-like | 49/201 (24.4) | 6/34 (17.6) | |
ASY2c/SY2c-like | 15/201 (7.5) | 13/34 (38.2) |
*SBI, Shiga toxin–encoding bacteriophage insertion.
†Values refer to differences between frequency distributions of SBI types and North and South Islands (χ2 and Fisher exact test).
1Preliminary results from this study were presented at the New Zealand Veterinary Association Conference; June 16–20, 2014, Hamilton, New Zealand.