Ntuli, VictorNjage, Patrick Murigu KamauBuys, E.M. (Elna Maria)2017-01-192017-03Ntuli, V, Njage, PMK & Buys, EM 2017, 'Extended-spectrum β-lactamase, shigatoxin and haemolysis capacity of O157 and non-O157 E. coli serotypes from producer-distributor bulk milk', International Dairy Journal, vol. 66, pp. 126-134.0958-6946 (print)1879-0143 (online)/10.1016/j.idairyj.2016.11.008http://hdl.handle.net/2263/58571We investigated for virulence genes (stx1, stx2 and hlyA), serotypes and extended-spectrum β-lactamases (ESBLs) producing capacity in O157 and non-O157 Escherichia coli isolated from producer-distributor bulk milk (PDBM). Fifteen different E. coli O-serogroups were observed from the isolates (n=121). The prevalence of stx1 and stx2 genes among the E. coli isolates was 8.3% and 11.6% (n=121), respectively, while 5.8% harboured both stx1 and stx2. Four E. coli isolates (3.3%) had ESBLs producing capacity, resisted multiple cephalosporins and aztreonam, and carried stx genes. Cluster analysis using GTG5 finger printing revealed a diversity of E. coli seropathotypes in PDBM which are known to be associated with human diarrhoeal diseases. These results highlight a potential risk posed on human health by the consumption of PDBM contaminated with pathogenic E. coli. A further quantitative risk assessment of the impact of pathogenic E. coli contamination in PDBM on human health is therefore recommended.en© 2016 Elsevier Ltd. All rights reserved. Notice : this is the author’s version of a work that was accepted for publication in International Dairy Journal. Changes resulting from the publishing process, such as peer review, editing, corrections, structural formatting, and other quality control mechanisms may not be reflected in this document. A definitive version was subsequently published in International Dairy Journal, vol. 66, pp. 126-134, 2017. doi : /10.1016/j.idairyj.2016.11.008.Bulk milkVirulence genes (stx1, stx2 and hlyA)Extended-spectrum β-lactamases (ESBLs)Producer-distributor bulk milk (PDBM)Postprint Article