title: Changes in incidence of hepatitis B in Ireland from 1970-1987.
abstract: This paper analyses data on 2,226 cases of Hepatitis B virus (HBV) infection detected during the years 1970 to 1987. Of those where information on risk-group was available (1,301), infection among intravenous drug-abusers accounted for the largest proportion (49%). Most became infected during and since an outbreak of hepatitis B and Delta hepatitis which originated in this group in 1980. A comparison of the data before and after the start of the outbreak among drug-abusers shows a marked increase in the number of HBV infections in non drug users, including haemophiliacs, homosexuals and health-care staff, and a dramatic decrease in hepatitis B following blood transfusion. A larger group (165 cases), many of whom are long-term healthy hepatitis B surface antigen carriers, were patients in institutions for the mentally handicapped (IMH). Most were detected recently during pre-vaccination sampling programmes. Others affected included visitors to and from high-incidence areas, tattooed persons, dialysis patients, persons born to infected mothers, and members of the security forces dealing with drug-abusers. In all, 8.4% of the hepatitis B cases detected were found to be carriers and 67% of these remained carriers in 1987 The mean duration of carriage was 3.25 years. Intravenous drug-abusers and IMH patients constituted the two largest groups of carriers. The running-three-yearly mean incidence of new cases of hepatitis B has levelled off below the peak of 1981. Although the number of cases among drug-abusers has apparently decreased, the number of cases among non drug-abusing groups has increased by 50%. (ABSTRACT TRUNCATED AT 250 WORDS)
authors.forename: A G
authors.initials: AG
authors.lastname: Shattock
authors.forename: L
authors.initials: L
authors.lastname: Jones
authors.forename: M
authors.initials: M
authors.lastname: O'Mahony
authors.forename: I B
authors.initials: IB
authors.lastname: Hillary
mesh_terms: D015331:Cohort Studies; D006509:Hepatitis B / Q000453:epidemiology*; D006801:Humans; D007494:Ireland / Q000453:epidemiology