Outbreak of norovirus gastroenteritis infection, Thailand.
Norovirus is a leading cause of gastrointestinal illness worldwide. We investigated an outbreak of gastrointestinal illness in Pattaya, Thailand, among participants of a course. We asked participants and family members to complete a questionnaire asking about symptoms, meals eaten, and foods consumed during the course. We collected stool samples from persons reporting illness and analyzed specimens for several viruses and enteropathogenic bacteria. We defined a case as a person having one or more episodes of diarrhea, with onset between 30 August and 1 September 2010, in a participant or family member who attended the course. Of 56 people who attended, 95% completed the questionnaire: nine met the case definition (attack rate, 17%). Common symptoms included abdominal cramps, nausea, fatigue, headache, and vomiting. Food items with elevated risk ratios included: crispy fish maw, dried squid, and cashew nut salad [risk ratio (RR) 5.1; 95% confidence interval (CI) 0.7-37]; assorted salad bar with dressing (RR 3.0; 95% CI 0.9-11); and seafood kebab (RR 5.8; 95% CI 0.8-43). Among ill persons, four (44%) provided stool samples and two (50%) were positive for norovirus. Our data suggest a foodborne outbreak of norovirus. Increased use of norovirus diagnostics as well as measures to prevent transmission may help identify additional outbreaks and improve control measures to limit the spread of outbreaks.
ASPH/CDC Allan Rosenfield Global Health Fellow, Bangkok, Thailand.
Katie S
KS
McCarthy
Ratigorn
R
Guntapong
Aree
A
Thattiyaphong
Piyada
P
Wangroongsarb
Aron J
AJ
Hall
Sonja J
SJ
Olsen
Timothy H
TH
Holtz
D000328:Adult; D017250:Caliciviridae Infections / Q000453:epidemiology*; D015331:Cohort Studies; D004196:Disease Outbreaks; D005243:Feces / Q000821:virology; D005260:Female; D005516:Food Microbiology; D005759:Gastroenteritis / Q000453:epidemiology* / Q000821:virology; D006801:Humans; D008297:Male; D008875:Middle Aged; D029322:Norovirus; D012307:Risk Factors; D013785:Thailand / Q000453:epidemiology