Trial of a combined test for the detection of HBsAg and anti-HBc.

A combined hepatitis test (Ausria/Core, Abbott Laboratories, Wiesbaden, West Germany) detects hepatitis B surface antigen by radioimmunoassay and antibody to the core antigen by enzyme immunoassay using a single bead. It was found to have comparable sensitivity to commercially available tests from the same manufacturer for each component. Reproducibility was satisfactory for both components. The combined test is simpler and cheaper to perform than two separate tests.

Hepatitis B and the dental profession: response to hepatitis B vaccine in Canadian dental personnel. A study by the Canadian Red Cross Collaborative Group.

Reports from North America and Western Europe based on the prevalence of hepatitis B virus markers and frequency of hepatitis B in dentists indicate that this professional group is at increased risk of HBV infection. We gave hepatitis B vaccine (Merck Sharp and Dohme) to 251 dental students and faculty/staff members at faculties of dentistry in three Canadian universities. Participants received three 20 micrograms doses of vaccine, at 0, 1 and 5.5 months. Anti-HBs was detected in 42.9 per cent of persons after the first dose of vaccine, in 96.8 per cent after the second dose and in 99.6 per cent after the third dose. A follow-up of 150 persons 22 months after the first dose of vaccine indicated that high or medium levels of anti-HBs were maintained in nearly 87 per cent of the participants and only six per cent had no detectable antibody. Female vaccinees in each age group developed anti-HBs more promptly, and more of them were in the high antibody-response range in comparison to male participants. There were no unacceptable reactions to the vaccine. Our favourable experience with this vaccine would support recommendations for its routine use among dental professionals in Canada and other countries where this group is at increased risk of HBV infection.

Hepatitis B surveillance: 4-year survey of staff in a National Blood Transfusion Service.

The prevalence of HBsAg and anti-HBs in personnel of the Canadian Red Cross Blood Transfusion Service (BTS) during 1979 was not found to be significantly different from that of staff first employed in 1978-1979 or from that found among voluntary blood donors. Between 1976 and 1979, 2525 individuals were tested, of whom 13 seroconverted to HBsAg-positive; 54% of these cases appeared to be accident-related. During the same period 29 staff developed anti-HBs; of these 21% were apparently accident-related. Actual rates of seroconversion were not calculated because of staff turnover. The data suggest that BTS employees do not constitute a 'high-risk' group.

Prevalence of HBsAg and HBsAg sub-types in the Canadian blood-donor population.

After 8 years of screening all blood donations in Canada for HBsAg, first by CIEP and later by RIA, the prevalence of HBsAg in the regular panel of "repeat" donors has been reduced from 267/10(5) to 39/10(5). Marked geographic variations exist, but the available data do not indicate whether the high prevalence of HBsAg in young adults, particularly males, may be a factor. The ad : ay subtype ratio across Canada is 2.0, but noticeable geographic differences are present, varying from 3.5 in Quebec to 0.5 in the Atlantic Provinces.