Occurrence of Escherichia coli, noroviruses, and F-specific coliphages in fresh market-ready produce

J Food Prot. 2004 Nov;67(11):2387-90. doi: 10.4315/0362-028x-67.11.2387.

Abstract

Forty samples of fresh produce collected from retail food establishments were examined to determine the occurrence of Escherichia coli, F-specific coliphages, and noroviruses. An additional six samples were collected from a restaurant undergoing investigation for a norovirus outbreak. Nineteen (48%) of the retail samples and all outbreak samples were preprocessed (cut, shredded, chopped, or peeled) at or before the point of purchase. Reverse transcription-PCR, with the use of primers JV 12 and JV 13, failed to detect norovirus RNA in any of the samples. All six outbreak samples and 13 (33%) retail samples were positive for F-specific coliphages (odds ratio undefined, P = 0.003). Processed retail samples appeared more likely to contain F-specific coliphages than unprocessed samples (odds ratio 3.8; 95% confidence interval 0.8 to 20.0). Only two (5.0%) retail samples were positive for E. coli; outbreak samples were not tested for E. coli. The results of this preliminary survey suggest that F-specific coliphages could be useful conservative indicators of fecal contamination of produce and its associated virological risks. Large-scale surveys should be conducted to confirm these findings.

MeSH terms

  • Coliphages / isolation & purification*
  • Consumer Product Safety
  • Disease Outbreaks
  • Escherichia coli / isolation & purification*
  • Feces / microbiology
  • Feces / virology
  • Food Contamination / analysis
  • Food Contamination / prevention & control
  • Food Microbiology*
  • Humans
  • Norovirus / isolation & purification*
  • RNA, Viral / isolation & purification
  • Restaurants / standards
  • Vegetables / microbiology*
  • Vegetables / virology

Substances

  • RNA, Viral