Zoonotic Importance of Some Pathogenic Bacteria Isolated from Small Ruminants' Milk and Hands of Dairy Workers

Abstract

Staphylococcus aureus and enteropathogenic Escherichia coli are among zoonotic bacterial food-borne pathogens causing illness ranged from diarrhoea to fatal conditions. This study was undertaken to evaluate the occurrence of Staph. aureus and E. coli in small ruminants' raw milk and hands of dairy workers at small-scale production units, Giza, Egypt. A total of 420 raw milk samples were obtained from apparently healthy sheep and goats, also, hand swabs (n=46) from workers at the units under investigation were examined. Overall, Staph. aureus (13.1%, 55/420) and E. coli (26.2%, 110/420) isolates were obtained from raw milk of sheep and goats. However, only Staph. aureus (15.2%, 7/46) was recovered from hand swabs of dairy workers. Using PCR, all the tested Staph. aureus isolates from milk and hand swabs yielded specific bands of Thermonuclease (nuc) gene at 279 bp, however, amplification of virulence (eae) gene encoding the intimin protein of E. coli produced an amplicon of 917 bp in 45% of the tested E. coli isolates. In conclusion, our findings provide an overview about Staph. aureus and E. coli contamination in raw milk of small ruminants locally bred by smallholders and suggest probably transmission of Staph. aureus from hands of dairy workers that contaminate the milk or udder of apparently healthy animals. Reporting of such organisms from milk indicates the need for strict hygienic measures during milking at these production units.