During the 12 years from January, 1977, to December, 1988, the Hamilton Centre of the Canadian Red Cross Society (CRCS) Blood Transfusion Service screened 98,712 pregnant patients for hepatitis B surface antigen (HBsAg) and identified 120 positives (0.12%). The number of positives ranged from six to 16 per year. We were able to trace and enroll 65 mothers (54%) and 96 of their children in the follow-up study. The majority of the women were between 20 and 30 years of age (95.4%) and married (86%), and about one-half were employed outside the home. Sixty-five percent were white and 34% Asian, and 20 countries were listed as their places of origin. Hepatitis B immune globulin (HBIG) was available for neonatal immunization since 1977 and combined with vaccine since 1982. Of the 96 candidates for HBIG, 60 (63%) received HBIG within 24 hr, one after 3 months, four unknown, and 31 did not receive it. Of the 56 candidates for vaccination from 1982 to 1989, 26 (46%) received three doses, seven had two doses, eight had one dose, one was unknown, and 14 had none. HBsAg tests were performed on 69 children (71.8%) and anti-HBs on 61 (63.5%). Four of the children are HBsAg positive, 31 have anti-HBs, and 31 have no detectable antibodies. All four HBsAg positives had not received vaccine, and only one had received HBIG. Of the children positive for hepatitis B surface antibodies, five had received no immunization and therefore had been subclinically infected.(ABSTRACT TRUNCATED AT 250 WORDS)
To assess a hepatitis B vaccination program offered to all grade 6 students in British Columbia in 1992.
British Columbia, Canada.
All grade 6 students were offered vaccine. Subsets of 454 and 259 students participated in studies of minor adverse events and seroresponse, respectively.
The vaccine used was Engerix-B, 20 micrograms, given at intervals of 0, 1, and 6 months.
Province-wide acceptance and series completion rates and reports of severe adverse events. Minor adverse events and immunogenicity in subsamples.
A total of 127,922 vaccine doses were administered. Initial enrollment totaled 43,358 students or 95.4% of those eligible. The series was completed by 41,594 students (95.6%). Minor adverse events were infrequent in the cohort assessed: no absenteeism or physician visits resulted from vaccination. Sixty-nine reported severe adverse events met surveillance definitions, the major categories being injection site reactions (23% of reports), fainting (20%), and rashes (17%). There was one instance of anaphylaxis. Only 13 of these events resulted in recommendations to discontinue the series. Of students tested following the series, 98% had levels of antibody to hepatitis B surface antigen considered to be protective (> or = 10 IU/L), the geometric mean titer being 690 IU/L (95% confidence interval, 498 to 957 IU/L).
Our experience indicates that school-based programs for universal vaccination of preadolescents can be highly acceptable and efficient.
Comment In: JAMA. 1995 Oct 18;274(15):1242-37563516
Do selective immunisation against tuberculosis and hepatitis B reach the targeted populations? A nationwide register-based study evaluating the recommendations in the Norwegian Childhood Immunisation Programme.
Selective immunisation is an alternative to universal vaccination if children at increased risk of disease can be identified. Within the Norwegian Childhood Immunisation Programme, BCG vaccine against tuberculosis and vaccine against hepatitis B virus (HBV) are offered only to children with parents from countries with high burden of the respective disease. We wanted to study whether this selective immunisation policy reaches the targeted groups.
The study population was identified through the Norwegian Central Population Registry and consisted of all children born in Norway 2007-2010 and residing in Norway until their second birthday, in total 240,484 children. Information on vaccinations from the Norwegian Immunisation Registry, and on parental country of birth from Statistics Norway, was linked to the population registry by personal identifiers. The coverage of BCG and HBV vaccine was compared with the coverage of vaccines in the universal programme.
Among the study population, 16.1% and 15.9% belonged to the target groups for BCG and HBV vaccine, respectively. Among children in the BCG target group the BCG vaccine coverage was lower than the coverage of pertussis and measles vaccine (83.6% vs. 98.6% and 92.3%, respectively). Likewise, the HBV vaccine coverage was lower than the coverage of pertussis and measles vaccine in the HBV target group (90.0% vs. 98.6% and 92.3%, respectively). The coverage of the targeted vaccines was highest among children with parents from South Asia and Sub-Saharan Africa. The coverage of vaccines in the universal programme was similar in targeted and non-targeted groups.
Children targeted by selective vaccination had lower coverage of the target vaccines than of vaccines in the universal programme, indicating that selective vaccination is challenging. Improved routines for identifying eligible children and delivering the target vaccines are needed. Universal vaccination of all children with these vaccines could be considered.
BACKGROUND: The duration of protection after hepatitis B vaccination of infants is unknown. METHODS: We determined antibody to hepatitis B surface antigen (anti-HBs) at 4-13 years of age in 363 low risk children who had been vaccinated starting at birth with hepatitis B vaccine. Those with nonprotective titers ( or = 10 mIU/mL) of anti-HBs at 9 and 13 years, respectively. Of those who did not have protective antibody titers, 61% (33 of 54) and 67% (8 of 12), respectively, responded to a booster dose. In children of HBsAg-positive mothers, 31% retained protective anti-HBs at 12 years, and 90% (9 of 10) with nonprotective titers responded to a booster. In low risk children initially receiving a recombinant vaccine, 12.5% (26 of 208) and none (0 of 36) retained protective anti-HBs titers at 5 and 7 years of age, respectively. Of those who did not have protective titers, 90% (120 of 134) and 91% (32 of 35), respectively, responded to a booster. CONCLUSIONS: Anti-HBs disappeared by 5 years of age in most children who were vaccinated with hepatitis B vaccine from birth. Although most children showed immunologic memory, one-third failed to demonstrate an anamnestic response to a booster dose. Additional long term studies of low risk infants are needed to determine duration of protection and the necessity for or timing of booster doses.
In 1994, immunization against hepatitis B was implemented in schools in Quebec, targeting grade 4 students. In 1996-1997 and 1997-1998, one Local Community Service Centre (CLSC) replaced the school-based program in its district with vaccination offered in community clinics after school hours. The aim of the current study was to compare the effectiveness and costs of school-based and clinic-based programs.
Vaccination coverage data were collected in the CLSC with the clinic-based program (CBP), and in three matched CLSCs with a school-based program (SBP), from 1994 to 2000. Surveys were conducted to estimate costs to parents, to schools and to CLSCs in 1997-1998.
With the implementation of the CBP, the vaccination coverage fell to 73%, compared with over 90% in the SBPs. Coverage increased to 90% when the CBP was abandoned. Costs to the CLSC were not much lower in the CBP. Societal costs were $63 per student vaccinated in the CBP, and
Scientific evidence documenting the effectiveness of immunization delivery methods was summarized using the generic approach developed by the Community Health Practice Guidelines Working Group. The delivery methods examined were those for the adult and childhood vaccines of influenza, pneumococcal infection, hepatitis B, measles-mumps-rubella and diphtheria-pertussis-tetanus-polio. Based on a critical appraisal of 54 eligible comparative studies, the effects of different interventions were obtained and pooled effects were calculated for delivery methods oriented to the client, the provider and the system. The results indicate those interventions found to be most effective for each vaccine. This review of the scientific evidence of the effectiveness of immunization delivery methods provides a base for policy development and assists in the planning of resource allocation.
Hepatitis A and B vaccines are highly immunogenic in three-dose schedules. To obtain an equivalent result in children with two paediatric doses would be of significant benefit. The purpose of this study was to measure the immunogenicity of a two-dose schedule in children with two licensed recombinant HBsAg containing vaccines given at paediatric doses, one of them combined with hepatitis A. Seven-hundred and four healthy school children aged 8-10 years were recruited in an open label study to receive either Twinrix Pediatric (360 El.U HAV antigen; 10 microg HBsAg) or Recombivax (2.5 microg HBsAg) vaccine intramuscularly 6 months apart. The seroconversion (>/=1 mIU/ml for anti-HBs antibodies and >/=33 mIU/ml for anti-HAV antibodies), seroprotection (anti-HBs >/=10 mIU/ml) rates and the geometric mean titers (GMTs) were determined 4-8 weeks after the second dose. The anti-HBs seroconversion rate was 97.1% with Twinrix and 97.2% with Recombivax. The seroprotection rates were 96.5 and 94.4%, respectively (P = 0.17). The GMT was higher with Twinrix than with Recombivax (3248 mIU/ml versus 742 mIU/ml, P
Hepatitis B vaccine is effective in preventing infection with hepatitis B virus (HBV), but its duration of protection is unknown. To examine the effect of exposure to HBV on an immunized population, data were analyzed from a cohort of Alaska Natives who were immunized and then followed up annually for 10 years. A boost in antibody to hepatitis B surface antigen (anti-HBs) was defined as a fourfold rise in levels to > or = 20 mIU/mL that was not accompanied by the presence of antibody to hepatitis B core antigen or attributable to interim vaccination. During 10 years of follow-up, 8.2% of 1,595 vaccines had boosts in anti-HBs. Persons with boosts did not differ significantly from those without boosts in terms of age, gender, village, initial level of anti-HBs, or level of anti-HBs before the boost. These results underscore the continued exposure to HBV among vaccinees and the continued protection against disease that the vaccine provides.