A foodborne outbreak of gastroenteritis associated with Norwalk-like viruses: first molecular traceback to deli sandwiches contaminated during preparation

J Infect Dis. 2000 Apr;181(4):1467-70. doi: 10.1086/315365. Epub 2000 Apr 7.


In March 1998, an outbreak of acute gastroenteritis occurred among students at a Texas university. Overall, 125 ill students sought medical care. Case-control studies revealed that illness was significantly associated with eating foods from the university's main cafeteria deli bar on 9 and 10 March. Stool specimens from 9 (50%) of 18 ill students and samples of deli ham showed evidence of Norwalk-like viruses (NLVs) by reverse-transcriptase (RT) polymerase chain reaction (PCR) assay. A food handler who prepared sandwiches for lunch on 9 March reported that her infant had been sick with watery diarrhea since just before the outbreak. A stool sample from the infant was positive for NLV by RT-PCR, and the sequence of the amplified product was identical to that of amplified product from deli ham and students' stool specimens. This is the first time RT-PCR and sequence analysis have successfully confirmed viral contamination of a food item likely to have been contaminated by a food handler.

Publication types

  • Research Support, U.S. Gov't, Non-P.H.S.
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Caliciviridae Infections / epidemiology*
  • Caliciviridae Infections / transmission
  • Caliciviridae Infections / virology*
  • Case-Control Studies
  • Diarrhea / virology
  • Disease Outbreaks*
  • Feces / microbiology
  • Feces / virology
  • Female
  • Food Handling
  • Foodborne Diseases / epidemiology*
  • Foodborne Diseases / virology*
  • Gastroenteritis / epidemiology*
  • Gastroenteritis / virology*
  • Humans
  • Infant
  • Male
  • Norwalk virus*
  • Polymerase Chain Reaction
  • Texas
  • Universities