An outbreak of hepatitis A associated with green onions.
Forty-three cases of serologically confirmed hepatitis A occurred among individuals who ate at restaurant A in Ohio in 1998. Serum samples from all restaurant A employees who worked during the exposure period were negative for IgM antibodies to hepatitis A virus (HAV). A matched case-control study determined that foods containing green onions, which were eaten by 38 (95%) of 40 case patients compared with 30 (50%) of 60 control subjects, were associated with illness (matched odds ratio, 12.7; 95% confidence interval, 2.6-60.8). Genetic sequences of viral isolates from 14 case patients were identical to each other and to those of viral isolates from 3 patients with cases of hepatitis A acquired in Mexico. Although the implicated green onions, which could have come from one of 2 Mexican farms or from a Californian farm, were widely distributed, no additional green onion-associated cases were detected. More sensitive methods are needed to detect foodborne hepatitis A. A better understanding of how HAV might contaminate raw produce would aid in developing prevention strategies.
Dentinger
C M
CM
Hepatitis Branch, Centers for Disease Control and Prevention, 1600 Clifton Road, MS G-37, Atlanta, GA 30333, USA. cgd1@cdc.gov
Bower
W A
WA
Nainan
O V
OV
Cotter
S M
SM
Myers
G
G
Dubusky
L M
LM
Fowler
S
S
Salehi
E D
ED
Bell
B P
BP
D002140:California; D016022:Case-Control Studies; D004196:Disease Outbreaks; D005516:Food Microbiology; D006506:Hepatitis A / Q000453:epidemiology* / Q000635:transmission; D035922:Hepatitis A Antibodies; D006508:Hepatitis Antibodies / Q000097:blood; D006507:Hepatovirus / Q000145:classification / Q000235:genetics / Q000302:isolation & purification*; D006801:Humans; D008800:Mexico; D016017:Odds Ratio; D009820:Ohio / Q000453:epidemiology; D019697:Onions / Q000382:microbiology*; D010802:Phylogeny; D012147:Restaurants
D035922:Hepatitis A Antibodies; D006508:Hepatitis Antibodies