Risk factor analysis of an epidemic of hepatitis A in a factory in Shanghai.
Investigation of an epidemic of hepatitis A which occurred in Shanghai in early 1988 was conducted at the Shanghai No. 2 Yarn Dyeing and Weaving Mill. In this factory the attack rate between January and April 1988 was 9%. The rate was highest among staff who ate raw clams (18%) and higher among those who ate cooked clams (7%) than among those who did not eat clams (2%). In addition, independent risk factors for infection were: age below 30 years (relative risk (RR) = 3.0, 95% Cl: 2.0, 4.5) shift work (RR = 3.3, 95% Cl: 1.9, 5.8) and eating out (RR = 4.7, 95% Cl: 2.3, 9.7). Consumption of clams contaminated with hepatitis A was the main risk factor in this episode. The study indicates that strengthening surveillance of shellfish hygiene is important in preventing future epidemics of hepatitis A.
Wang
J Y
JY
Division of Gastroenterology, Zhong Shan Hospital, Shanghai Medical University, China.
Hu
S L
SL
Liu
H Y
HY
Hong
Y L
YL
Cao
S Z
SZ
Wu
L F
LF
D000328:Adult; D000367:Age Factors; D000704:Analysis of Variance; D000818:Animals; D049872:Bivalvia / Q000382:microbiology; D002681:China / Q000453:epidemiology; D003430:Cross-Sectional Studies; D003967:Diarrhea / Q000209:etiology; D004196:Disease Outbreaks / Q000706:statistics & numerical data*; D005260:Female; D005506:Food Contamination; D006506:Hepatitis A / Q000150:complications / Q000453:epidemiology*; D006507:Hepatovirus / Q000302:isolation & purification; D006801:Humans; D016015:Logistic Models; D008297:Male; D012147:Restaurants; D012307:Risk Factors