Immunogenicity and economic evaluation of different recombinant hepatitis-B vaccines in different dosages, schedules, and routes of administration

To measure the immunogenic response produced by recombinant DNA derived vaccines in different dosages, schedules, and routes of administration. Another objective was to evaluate the minimum dosage and compliant schedule of recombinant DNA derived vaccine required to produce effective immune response and its economic evaluation in the adult population. Five hundred fifty eight healthcare workers in the age group of 20-50 years from Military Hospital Rawalpindi, Pakistan and other sister institutions were enrolled. Two hundred fifty eight were excluded due to serological evidence of HBV infection. Remaining three hundred were divided into five groups each having sixty volunteers with equal male to female ratio and age groups 20-29,30-39, 40-50. First four groups were injected with Heberbiovac vaccine and last group-V was given inj. Engerix-B. In Heberbiovac arm: Group-I received standard dose of 20Microg at standard schedule of zero, one and six months intramuscularly. In Group-II, dose was reduced to half [10Microg] intramuscularly. Group-III was given only two standard doses of 20Microg at zero and one month interval intramuscularly and Group-IV received intradermal dose of 3Microg at zero, one and six months. Group-V was given Engerix -B in standard dosage and schedule, [i.e., 20Microg at zero, one and 6 months]. Immunogenic response was measured in all the groups eight weeks after the last dose. Response was measured with MEIA/IMX system by ABBOTT. Both the vaccines were equally immunogenic but higher titers of Anti HBs was achieved with Heberbiovac. In Heberbiovac arm of study, seroprotection rate was 96.36% in Group-I, in Group-II it was 94.64%, in Group-III 95% and in intradermal group 98.14%. In Engerix -B group it was 92%. Two doses/Half dose schedule/intradermal route of 3Microg of Inj. Heberbiovac is equipotent to that of standard dose/schedule of Inj. Heberbiovac or Inj. Engerix-B in terms of seroprotection rate achieved

Routine hepatitis B immunisation in India: cost-effectiveness assessment.

Based on World Bank guidelines, hepatitis B immunization would be an excellent public health investment, saving each life year for well below the per-capita gross domestic product. This would be one of the most cost-effective investments India could make in the field of health.

Differences in hepatitis B markers between clinical and preclinical health care personnel.

Hepatitis B virus (HBV) infection is an occupational risk for health care personnel (HCP). Vaccination is an important preventive measure but high cost of vaccination limits the feasibility of giving vaccine to all HCP. To find an optimum approach for vaccination we conducted a study on HCP in Maulana Azad Medical College and associated LNJPN hospital. A total of 162 subjects were screened. Eight were excluded because of prior vaccination against HBV. Two groups of subjects were selected namely preclinical and clinical. The preclinical group comprised first year medical students and the clinical group comprised of HCP who have been exposed to clinical departments. The subjects were screened for HBsAg, anti HBs and anti HBc viral markers. 86 subjects were screened in the preclinical group. Two (2.3%) were positive for HBsAG; 16 (18%) and 9 (10.4%) were positive for anti HBs and anti HBc respectively. In the clinical group a total of 68 subjects were screened. Amongst them 1.4% were positive for HBsAg; 47 (69%) and 38 (55%) were positive for anti HBs and anti HBc respectively. The study revealed that there was a significant difference in the titre of the viral markers in the preclinical group as compared to the clinical group. Seventy (82%) of preclinical subjects were at high risk for the infection as they moved into clinical departments. Few subjects will be excluded from the vaccination schedule based on anti HBs screening and hence screening prior to vaccination is not cost effective. However in the clinical group 69% will be excluded from the vaccination schedule based on anti HBs positivity and screening will save up to 60% of cost involved in vaccination.

Protective antibody after a 'one dollar' hepatitis B vaccine.

The seropositivity rate of anti-HBs after hepatitis B vaccines, "Hepavax B", a one-dollar per dose vaccine produced by Korean Green Cross Corporation, Korea which were widely distributed and used for the first few years in the National Expanded Program on Immunization in Thailand were assessed in children who regularly came for immunization at the Well Baby Clinic at the Children's Hospital between June to December 1994. The schedule for hepatitis B immunization is at birth, 2 and 6 months of age. The seropositivity rate of anti-HBs at 6 months after the last dose were 86.3% and 87.7% at 12 months which was comparable to the seropositivity rate after other more expensive hepatitis B vaccines at 2 years (88.1%). This result should convince people that a one-dollar hepatitis B vaccine, "Hepavax" is immunogenic and expected to be as effective as other expensive hepatitis B vaccines. The marked reduce in the cost of hepatitis B vaccines will enable us to prevent and ultimately control of worldwide hepatitis B infections in the future.

Otimizaçäo do emprego de recursos econômicos para vacinaçäo contra hepatite B em profissionais da área de saúde / Application optimizing of economic resources to be allocated for hepatitis B vaccination programs involvinh health care workers

In order to optimize the employment of financial resources to be allocated for hepatitis B vaccination programs involving health care workers, two different aspects were studied: the need of a pre-vaccination screening and the efficacy of low-doses schedules of HBV vaccine by the intradermal (ID) route. The economical analysis (a cost-minimization study) showed that when the prevalence of immune individuals is higher than 11 per cent it is more cost-effective to perform pre-vaccination screening. This situation was observed in the employees group. For students and doctors vaccination without screening was the best approach. Regarding the schedules, 3 doses of HBV vaccine by the intramuscular (IM) route (group A) were compared to first dose by the ID route and second and third doses by the IM route (group B) and to first and second doses by the ID route and the last dose by the IM route (group C). After the third dose, soroconversion rates in groups A and B (92 per cent and 93 per cent, respectively) and geometric mean titers of antiHBs (1278 UI/L and 789.6 UI/L) were similar, and both were different from group A (p < 0.05), showing that alternative vaccination schedules may be cost-effective.