Hepatitis B in adolescence and middle-age.

In 1983 304 serum samples, and in 1984 432 serum samples submitted to the Hepatitis Reference Laboratory, Ruchill Hospital, Glasgow were found to be positive for HBsAg by radio-immunoassay. Of these, 37 in 1983 and 50 in 1984 were from persons less than 18 years, while 38 and 46 respectively were from persons greater than 39 years. This increase from 1983 to 1984 was due to more acute infections among males. In males less than 18 years, infections were related to drug abuse, whereas in men greater than 39 years sexual transmission appeared to be the main source. Women greater than 39 years may be at increased risk of infection from other members of the household. A finding of HBsAg in a person greater than 39 years is likely to be from an acute infection as from a carrier.