Abstract

This study was conducted to investigate the microbiological quality of raw cow’s milk in a collection center in the city of Mashhad, Iran. A total of 19 raw cow’s milk samples were collected and simultaneously analyzed for male-specific (F<sup>+</sup>) coliphage and Escherichia coli using culture-based methods and for enteric viruses by reverse transcriptase semi-nested PCR using primer sets specific for human norovirus Group I (HNV-GI), human norovirus Group II (HNV-GII), and enteroviruses (EV). Seven out of 19 (36.8 %) raw milk samples tested positive for human noroviruses (HNV). The genotypes detected were HNV-GI and HNV-GII. Three positive samples contained both genotypes, and 2 samples were positive for either of HNV-GI and HNV-GII. No sample tested positive for EV. The correlation between the occurrence of HNV and the microbial indicators was studied. The statistical analysis using first- and second-order regression revealed that there is no correlation between F<sup>+</sup> coliphage and E. coli. Similarly, no correlation was noticed between the occurrence of F<sup>+</sup> coliphages and HNV. However, frequency distribution analysis indicated that 3 out of 4 (75 %) of raw milk samples containing F<sup>+</sup> coliphage at a concentration higher than 10<sup>4</sup> pfu/100 ml were also positive for noroviruses. The limited data on the occurrence of noroviruses in raw milk suggest a poor sanitation and hygiene practices at the facility and indicate a possible correlation between the viral indicator at high concentration and human noroviruses; however, this analysis needs further investigation in a larger scale study.

Original languageEnglish (US)
Pages (from-to)232-238
Number of pages7
JournalFood and Environmental Virology
Volume7
Issue number3
DOIs
StatePublished - Sep 10 2015

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Keywords

  • Coliphage
  • E. coli
  • Enteroviruses
  • Norovirus
  • Raw milk

ASJC Scopus subject areas

  • Epidemiology
  • Health, Toxicology and Mutagenesis
  • Food Science
  • Virology

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