Immunization Science

Impact of Hepatitis B Vaccine

The article

Elimination of acute hepatitis B among adolescents after one decade of an immunization program targeting Grade 6 students. Patrick DM, Bigham M, NG H, White R, Tweed A, and Skowronski DM. The Pediatric Infectious Disease Journal 2003;22(10):874-878

The question

What has been the impact of preadolescent immunization with hepatitis B vaccine?

The study

Canadian researchers studied the impact of the hepatitis B (HB) immunization program implemented in British Columbia in 1992 for children age 11. They collected data on vaccine uptake from school records and on HB infections from the public health information system.

What are some common characteristics of adolescents who became infected with HB? To answer that question, the researchers analyzed the variation in rates by vaccine uptake, urban vs. rural region of residence, gender, age and year of reporting in 12- to 20-year-olds.

The findings

Ten years after the implementation of the immunization program, HB infection was eliminated in the vaccinated group—adolescents and young adults. There was also a 50% decline in HB infection in the general population.

The researchers wrote that “the rate [of HBV infection] in the cohort of adolescents and young adults who were eligible to have received vaccines since 1993 fell from 1.7 to 0.0 per 100,000 in 2001. The cohort [persons in that age group] eligible for immunization during the 10-year period was 500,000, so that a rate of 0.0 per 100,000 in 2001 suggests that person-to-person HB transmission within this age group has been eliminated. No further acute HB was reported in this age group during 2002.”

The immunization program appeared to be more effective in rural areas. However, that might be the result of more HB carriers and exposure to HB in urban areas.

The relevance/bottom line

Immunization of preadolescents with hepatitis B vaccine eliminated infections in adolescents in British Columbia. The results of this study show the effectiveness of the hepatitis B vaccine.

NNii’s comment

This experience demonstrates the effectiveness of HB vaccine in reducing the transmission and, therefore, the complications of HB. Since 2001, British Columbia has begun universal infant hepatitis B immunization.