| hepatitis a sero-epidemiology in singapore: a changing pattern. | sera from 896 healthy volunteers between 15 and 56 years old were tested in 1987-1991 for immunoglobulin g antibody against the hepatitis a virus (igg anti-hav). the overall seroprevalence rate of igg anti-hav was 27%: it increased from 0.9% in the 10-19 years age group to 48.1% in the 40-49 years age group and was 100% in subjects over 50 years. there was no difference in anti-hav seroprevalence between the sexes (29% among men and 26% among women) and races. a downward trend in anti-hav seropr ... | 1993 | 8385369 |
| prevalence of hepatitis a virus infection among sewage workers in singapore. | to determine whether or not occupational exposure to sewage is associated with a higher seroprevalence of hepatitis a virus (hav) infection, 600 sewage workers in singapore were tested for total (igg and igm) antibody to hav by enzyme immunoassay. using logistic regression with stepwise procedure, the adjusted seroprevalence of sewage workers was 2.2 times higher than that of another non-occupationally exposed population group. seroprevalence was significantly correlated with age and educational ... | 1994 | 8062868 |
| acute hepatitis a in singapore: importance of shellfish ingestion in a non-epidemic period. | a case-control study based on 28 serologically confirmed cases of hepatitis a and 42 home contacts with no recent or past evidence of hepatitis a virus (hav) infection was conducted to determine the importance of shellfish exposure in the transmission of hav during a non-epidemic period in singapore. it was found that consumption of partially-cooked cockles (anadara granosa) was significantly associated with the illness (p less than 0.001). no other types of locally available shellfish including ... | 1987 | 2833148 |