Randomized clinical trial comparing hepatitis B vaccine administered by 0, 6 and 14 week versus 6, 10 and 14 week schedule in healthy infants

Prevalence and incidence rates of laboratory-confirmed hepatitis B infection in South Africa, 2015 to 2019

Background

Hepatitis B virus (HBV), a global public health threat, is targeted for elimination by 2030. As national HBV prevalence and incidence is lacking for South Africa, our study aimed to provide such data in the public health sector.

Methods

We analysed laboratory-confirmed HBV data from 2015 to 2019 to determine annual prevalence and incidence rates of HBV infection per 100,000 population, HBsAg and anti-HBc IgM test positivity rates, and HBsAg and anti-HBc IgM testing rates per 100,000 population. Time trend and statistical analyses were performed on HBsAg and anti-HBc IgM test positivity rates.

Results

The national prevalence rate of HBV infection per 100,000 population increased from 56.14 in 2015 to 67.76 in 2019. Over the five years, the prevalence rate was higher in males than females, highest amongst individuals 25 to 49 years old and highest in Gauteng province. The HBsAg test positivity rate dropped from 9.77% in 2015 to 8.09% in 2019. Over the five years, the HBsAg test positivity rate was higher in males than females, amongst individuals 25 to 49 years old and amongst individuals of Limpopo province. Amongst HBsAg positive children under 5 years old, the majority (65.7%) were less than a year old. HBsAg testing rates per 100,000 population were higher in females under 45 years of age and in males 45 years and above. The national incidence rate of acute HBV infection per 100,000 population dropped from 3.17 in 2015 to 1.69 in 2019. Over the five-year period, incidence rates were similar between males and females, highest amongst individuals 20 to 39 years old and highest in Mpumalanga province. Amongst individuals 20 to 24 years old, there was a substantial decline in the incidence and anti-HBc IgM test positivity rates over time. Anti-HBc IgM testing rates per 100,000 population were higher in females under 40 years of age and in males 40 years and above.

Conclusion

Critical to hepatitis B elimination is strengthened infant vaccination coverage and interruption of vertical transmission. Transmission of HBV infection in adults may be reduced through heightened awareness of transmission routes and prevention measures.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-12391-3.

Assessment of the anti-HBs antibody response in Beninese infants following 4 doses of HBV vaccine, including administration at birth, compared to the standard 3 doses regime; a cross-sectional survey

Hepatitis B virus (HBV) infection remains one of the major neglected health issues worldwide. In sub-Saharan Africa (SSA), HBV endemicity is high, with more than 8% of the population being chronic HBV carriers. Recently, WHO recommended that all infants should receive their first dose of the HBV vaccine as soon as possible after birth. Unfortunately, the incorporation of a birth dose of HBV in the expanded programme immunization (EPI) has not occurred in the majority of countries in SSA. From April to September 2017, a cross-sectional survey was conducted in two vaccine units located in southern Benin. We assessed the sustained anti-HBs antibody response in infants induced by a standard scheme of 3 doses of HBV vaccination (6, 10, 14 weeks) in comparison to a scheme of 4 doses with a birth dose included (0, 6, 10, 14 weeks). Blood samples were systematically collected in the first 140 children aged 9 months and their mothers who had consented to participate for the detection of HBs antigen and the quantification of anti-HBs antibodies. The prevalence of HBV infection among infants and mothers was 2.2% and 7.1%, respectively. Infants who received 4 doses of HBV vaccine had a significantly higher level of anti-HBs antibody than those who received 3 doses of vaccine (557.9 UI/L vs. 386.9 UI/L, respectively, P = 0.03). We also showed that the scheme of 4 doses was associated with a significantly higher sustained protective response in comparison to the scheme of 3 doses (aOR 2.49, 95% CI 1.03-6.03, P = 0.04). This result provides further evidence of the importance of administering HBV vaccine at birth, but also highlights the importance for the prevention of vertical transmissions. Additional studies are needed to better establish the cost-effectiveness of such a 4 doses immunization strategy before implementing the HBV vaccination at birth in the EPI.

Immunogenicity of recombinant hepatitis B vaccine: comparison of two different vaccination schedules

BACKGROUND

Neonatal immunization with hepatitis B (HB) vaccine induces protective levels of antibody (anti-HBs > or =10 IU/L) in a majority of vaccines. However, the duration of protection after HB vaccination in infants is unknown. A smaller proportion of children vaccinated beginning at birth with three doses of HB vaccine were found to have protective titers 5-10 years after initial vaccination. Long-term efficacy of HB vaccine depends mainly on peak antibody levels after vaccination, and subjects were observed to have lower levels of antibodies if they received the first dose of vaccine immediately after birth. The aim of our study was to compare the immunogenicity of two different HB vaccine schedules in infants born to HB surface antigen-negative mothers.

METHODS

Anti-HBs titers in infants vaccinated with two different schedules were compared. Infants were vaccinated at 0, 2, and 9 months (group 1) or at 2, 4, and 9 months (group 2). In total, 267 blood samples were analyzed at a mean of 14.20 +/- 2.39 months after the third vaccine dose. Sera were tested for hepatitis B surface antigen (HBsAg), hepatitis B surface antibody (anti-HBs), and hepatitis B core antibody (anti-HBc) using commercial enzyme immunoassay kits.

RESULTS

The geometric mean titers for anti-HBs were 95.00 and 379.51 IU/L and the rates of anti-HBs more than > or =100 IU/L were 57.7 and 94.9% in group 1 and 2 infants, respectively.

CONCLUSION

Delaying the first dose of the HB vaccine until 2 months after birth produces a higher immune response and can provide longer term protection.