title: A foodborne outbreak of gastroenteritis associated with Norwalk-like viruses: first molecular traceback to deli sandwiches contaminated during preparation.
abstract: 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.
authors.affiliation: Foodborne and Diarrheal Diseases Branch, Division of Bacterial and Mycotic Diseases, Atlanta, GA 30333, USA.
authors.forename: N A
authors.initials: NA
authors.lastname: Daniels
authors.forename: D A
authors.initials: DA
authors.lastname: Bergmire-Sweat
authors.forename: K J
authors.initials: KJ
authors.lastname: Schwab
authors.forename: K A
authors.initials: KA
authors.lastname: Hendricks
authors.forename: S
authors.initials: S
authors.lastname: Reddy
authors.forename: S M
authors.initials: SM
authors.lastname: Rowe
authors.forename: R L
authors.initials: RL
authors.lastname: Fankhauser
authors.forename: S S
authors.initials: SS
authors.lastname: Monroe
authors.forename: R L
authors.initials: RL
authors.lastname: Atmar
authors.forename: R I
authors.initials: RI
authors.lastname: Glass
authors.forename: P
authors.initials: P
authors.lastname: Mead
mesh_terms: D000293:Adolescent; D000328:Adult; D017250:Caliciviridae Infections / Q000453:epidemiology* / Q000635:transmission / Q000821:virology*; D016022:Case-Control Studies; D003967:Diarrhea / Q000821:virology; D004196:Disease Outbreaks; D005243:Feces / Q000382:microbiology / Q000821:virology; D005260:Female; D005511:Food Handling; D005517:Foodborne Diseases / Q000453:epidemiology* / Q000821:virology*; D005759:Gastroenteritis / Q000453:epidemiology* / Q000821:virology*; D006801:Humans; D007223:Infant; D008297:Male; D009663:Norwalk virus; D016133:Polymerase Chain Reaction; D013781:Texas; D014495:Universities