Hepatitis B Vaccination among 1999⁻2017 Birth Cohorts in Zhejiang Province: The Determinants Associated with Infant Coverage

Evaluating the potential cost-effectiveness of microarray patches to expand access to hepatitis B birth dose vaccination in low-and middle-income countries: A modelling study

Timely birth dose vaccination is key for achieving elimination of hepatitis B, however, programmatic requirements for delivering current vaccine presentations to births outside of health facilities inhibits coverage within many low-and middle-income countries (LMICs). Vaccine technologies in development such as microarray patches (MAPs) could assist in overcoming these barriers, but procurement could incur higher per-dose commodity costs than current ten-dose (US$0.34) and single-dose (US$0.62) vial presentations, necessitating an evaluation of the economic value proposition for MAPs. Within 80 LMICs offering universal hepatitis B birth dose vaccination, the cost-effectiveness of using MAPs to expand coverage was evaluated using a mathematical model. We considered three potential per dose MAP prices (US$1.65, US$3.30, and US$5.00), and two potential MAP use-cases: (1) MAPs are used by lay-health workers to expand birth dose coverage outside of health facility settings, and (2) MAPs are also preferred by qualified health workers, replacing a proportion of existing coverage from vaccine vials. Analysis took the health system perspective, was costed in 2020 US$, and discounted at 3% annually. Across minimal (1% additional coverage) and maximal (10% additional and 10% replacement coverage) MAP usage scenarios, between 2.5 (interquartile range [IQR]: 1.9, 3.1) and 38 (IQR: 28,44) thousand DALYs were averted over the estimated 2020 birth cohort lifetime in 80 LMICs. Efficiency of MAPs was greatest when used to provide additional coverage (scenario 1), on average saving US$88.65 ($15.44, $171.22) per DALY averted at a price of US$5.00 per MAP. Efficiency was reduced when used to replace existing coverage (scenario 2); however, at prices up to US$5.00 per MAP, we estimate this use-case could remain cost-effective in at least 73 (91%) modelled LMICs. Our findings suggest even at higher procurement costs, MAPs are likely to represent a highly cost-effective or cost-saving mechanism to expand reach of birth dose vaccination in LMICs.

Vaccination against tuberculosis, polio and hepatitis B at birth in Podor health district, Northern Senegal: cross-sectional study of vaccination coverage and its associated factors

BACKGROUND

In Senegal, studies focusing specifically on vaccination coverage with the Bacille de Calmette et Guérin (BCG) vaccine, the birth dose of oral polio vaccine (OPV zero dose) and the birth dose of hepatitis B (HepB-BD) vaccine are insufficient. This study aimed to highlight vaccination coverages with birth doses and factors associated with timely vaccination in Podor health district.

METHODS

A cross-sectional study was carried out from June 19 to 22, 2020. The study population consisted of children aged 12 to 23 months of which 832 were included. A stratified two-stage cluster survey was carried out. The sources of data were home-based records (HBR), health facility registries (HFR) and parental recalls. Timely vaccination refers to any vaccination that has taken place within 24 h after birth. Descriptive analyzes, the chi-square test and logistic regression were performed.

RESULTS

The crude vaccination coverages with BCG, OPV zero dose and HepB-BD were 95.2%, 88.3% and 88.1%, respectively. Vaccination coverages within 24 h after birth were estimated at 13.9%, 30% and 42.1%, respectively. The factors associated with timely HepB-BD are delivery in a health facility (AOR = 1.55; 95% CI = 1.02-2.40), access to television (AOR = 1.63; 95% CI = 1.16-2.29), weighing (AOR = 3.92; 95% CI = 1.97-8.53) and hospitalization of the newborn immediately after birth (AOR = 0.42; 95% CI = 0.28-0.62).

CONCLUSION

Timely administration of birth doses is a challenge in the Podor health district. The solutions would be improving geographic access to health facilities, involving community health workers, raising awareness and integrating health services.

Anti-HBs levels in children under the age of two years born to HBV carrier mothers after immunoprophylaxis: a multicenter cross-sectional study

BACKGROUND

Serological testing for the presence of Hepatitis B Virus (HBV) markers and anti-HBs titers in infants born to HBsAg positive women is critically important for estimation in immunisation programme.

METHODS

This was a multi-center and cross-sectional study conducted in Zhejiang province, China. Children aged 7 to 24 months born to HBsAg positive women during December 2018 to February 2019, completed additional HBV serological markers screening. We indicated distribution of HBV serological markers and anti-HBs titers in children. Multiple logistic regression model with adjusted odds ratio and 95% confidence interval (ORadj and 95% CI) was used to explore the factors associated with inadequate immune response (anti-HBs titers< 100 mIU/ml) among children.

RESULTS

A total of 1849 children were included. Overall 25 children tested HBsAg positive, giving HBsAg positive rate of 1.35%(95%CI: 0.83-1.88%). 92.00% (23/25) HBsAg positive children were delivered by HBeAg positive mothers. The proportion of protective seroconversion (anti-HBs titers≥10mIU/ml) was 99.29% in all children, and 86.48% children were reported with adequate anti-HBs titers (≥100mIU/ml).We found a significant higher proportions of early antenatal health care (< 13 gestational weeks), and term birth in children with adequate response compared with inadequate response (all P < 0.05). Logistic regression showed preterm birth was a negative factor for inadequate anti-HBs titers (ORadj = 1.868,95%CI 1.132-3.085,P = 0.015).

CONCLUSIONS

Children delivered by HBeAg positive mothers had higher risk of vertical transmission of HBV, despite completion of 3 doses of hepatitis B vaccine and HBIG injection. Inadequate anti-HBs level was significantly associated with preterm birth in HBsAg positive women.

Seroprevalence of hepatitis B antibodies among international and domestic university students

Chronic hepatitis B prevalence is low in most Australian populations, with universal infant HBV vaccination introduced in 2000. Migrants from high prevalence countries are at risk of acquisition before arrival and non-immune adults are potentially at risk through skin penetrating procedures and sexual contact, particularly during international travel. The risk profile of young adult students, many from high prevalence countries, is inadequately understood. A cross-sectional online survey conducted among university students collected data on demographic, vaccination and travel characteristics and blood samples were tested for hepatitis B surface antibody (HBsAb) and hepatitis B core antibody (HBcAb). Analyses identified factors associated with HBsAb seroprevalence and self-reported vaccination. The serosurvey was completed by 804 students born between 1988 and 1993, with 613/804 (76.2%, 95% CI 73.2-79.1) self-reporting prior HBV vaccination. Overall, 526/804 (65.4%, 95% CI 62.0%-68.6%) students were seropositive to HBsAb, including 438/613 (71.5%, 95% CI 67.8-74.9) students self-reporting a prior HBV vaccine and 88/191 (46.1%, 95% CI 39.2-53.2) students self-reporting no prior HBV vaccine. Overall, 8/804 (1.0%, 95% CI 0.5%-2.0%) students were HBcAb positive, of whom 1/804 (0.1%, 95% CI 0.02%-0.7%) was currently infectious. The prevalence of chronic HBV infection was low. However, more than one in four students were susceptible to HBV and over-estimated their immunity. Future vaccination efforts should focus on domestic students born before the introduction of the infant program and all international students. Screening and vaccination of students, including through campus-based health services, are an opportunity to catch-up young adults prior to undertaking at-risk activities, including international travel.

Influencing factors and necessity of post-vaccination serologic testing follow-up for HBsAg-positive mothers and their infants: A 5-year prospective study in Zhejiang Province, China (2016-2020)

In 2016, China officially proposed for the first time that infants born to HBsAg-positive mothers should be tested for HBsAg and anti-HBs 1-2 months after their third dose of HepB, also known as the post-vaccination serological testing programme. This study aimed to systematically evaluate the implementation and influencing factors of PVST to further reduce HBV infection risk in infants and improve the protective effect of HepB to the greatest extent. A prospective observational study was conducted to investigate the interruption of MTCT of hepatitis B. Univariate and multivariate analyses were applied to explore factors associated with the PVST follow-up rate among HBsAg-positive mothers and their infants. Additionally, bivariate analysis was performed on HBsAg and anti-HBs results in infants born to HBsAg-positive mothers. Here, the participation rate of PVST was 67.08% among 2120 pairs of positive mothers and infants. The HBsAg-positive rate among participants was 0.77%, whereas the anti-HBs positive rate was 96.84%, and both negative rates were 2.39%. Among infants with double negative results (34), only 15 completed three doses of HepB and PVST again, and 14 (93.33%) of which the antibody test results turned positive. Older mothers with high educational levels who reside in the local area were the most likely to PVST follow-up. The PVST programme is necessary to evaluate the HepB response status of newborns after vaccination. Moreover, revaccination for susceptible infants can effectively improve the MTCT-blocking rate of hepatitis B. Therefore, the scope of PVST projects in Zhejiang and China should be expanded.

Use of controlled temperature chain and compact prefilled auto-disable devices to reach 2030 hepatitis B birth dose vaccination targets in LMICs: a modelling and cost-optimisation study

BACKGROUND

Hepatitis B causes more than 800 000 deaths globally each year. Perinatal infections are a major driver of this burden but can be prevented by vaccination within 24 h of birth. Currently, only 44% of newborn babies in low-income and middle-income countries (LMICs) receive a timely birth dose. We investigated the effects and cost-effectiveness of implementing ambient storage of hepatitis B vaccines under a controlled temperature chain (CTC) protocol and the use of compact prefilled auto-disable (CPAD) devices for community births.

METHODS

In this mathematical modelling study of perinatal hepatitis B transmission and disease progression, we estimated the coverage impact and cost-effectiveness of implementing CTC and CPAD interventions in the six Global Burden of Disease (GBD) regions containing LMICs. Combinations of four different scenarios of birth dose delivery strategies (cold chain, CTC) and interventions (needle and syringe, CPAD) were modelled across facility or community birth locations. We also estimated the minimum cost and most cost-effective strategy to achieve the WHO 90% hepatitis B birth dose coverage target in GBD regions and in 46 LMICs with a reported coverage of less than 90%.

FINDINGS

Current delivery protocols achieved a maximum coverage of 65% (IQR 64-65) across GBD regions. Reaching 90% hepatitis B birth dose coverage across all GBD regions was estimated to cost a minimum of US$687·5 million per annum ($494·0 million more than the estimated current expenditure), of which $516·5 million (75%) was required for CTC and CPAD interventions. Reaching 90% coverage in this way was estimated to be cost saving in five of the six regions (and in 40 of 46 LMICs individually assessed) due to the disease costs averted, with the cost per disability-adjusted life-years averted being less than $83·27 otherwise.

INTERPRETATION

Hepatitis B birth dose coverage of 90% is unlikely to be reached under current protocols. CTC and CPAD vaccine strategies present cost-effective solutions to overcome coverage barriers.

FUNDING

The Burnet Institute.

Study on Status and Willingness towards Hepatitis B Vaccination among Migrant Workers in Chongqing, China: A Cross-Sectional Study

Background: Rural-to-urban migrant workers may serve as a bridge population for the cross-regional spread of hepatitis B vaccination (HBV) due to frequent shifts between their work areas and homelands, and they are less likely to be covered by the national hepatitis B (HB) immunization program. This study aimed to investigate the current inoculation status of HB vaccine among migrant workers and the willingness to be vaccinated among non-vaccinated ones. Methods: We conducted a cross-sectional survey using anonymous interviews with migrant workers selected by two-stage cluster sampling from July to December 2018. Binary logistic regression models were adopted to detect influencing factors associated with HB inoculation status and vaccination willingness. Results: 1574 respondents were recruited in the surveys, and 773 (49.11%) respondents reported that they had been inoculated with HB vaccine. Only 285 (35.58%) non-vaccinated respondents were willing to be inoculated. Logistic regression indicated that younger age, higher education level, less wearing of condoms, higher knowledge scores of HB, and higher risk perception of HBV infection were positively associated with inoculation of HB vaccine. Respondents who were more highly educated, and drinkers, with higher knowledge scores of HB and with higher risk perception of HBV infection were more willing to be vaccinated. Conclusions: the HB vaccination rate of migrant workers in Chongqing was relatively low and only a small section of non-vaccinated migrant workers had vaccination willingness. Health interventions and policies are needed to improve knowledge and cognition of HB among migrant workers, particularly for those who are older, less educated, poor in HB knowledge, less likely to wear condoms, and non-drinkers. Peer education, as well as the combination of traditional and new media, would be accessible and effective ways to disseminate HB related knowledge for migrant workers.

Host Genetic Determinants of Hepatitis B Virus Infection

Chronic hepatitis B virus (HBV) infection is still a major health problem worldwide. Recently, a great number of genetic studies based on single nucleotide polymorphisms (SNPs) and genome-wide association studies have been performed to search for host determinants of the development of chronic HBV infection, clinical outcomes, therapeutic efficacy, and responses to hepatitis B vaccines, with a focus on human leukocyte antigens (HLA), cytokine genes, and toll-like receptors. In addition to SNPs, gene insertions/deletions and copy number variants are associated with infection. However, conflicting results have been obtained. In the present review, we summarize the current state of research on host genetic factors and chronic HBV infection, its clinical type, therapies, and hepatitis B vaccine responses and classify published results according to their reliability. The potential roles of host genetic determinants of chronic HBV infection identified in these studies and their clinical significance are discussed. In particular, HLAs were relevant for HBV infection and pathogenesis. Finally, we highlight the need for additional studies with large sample sizes, well-matched study designs, appropriate statistical methods, and validation in multiple populations to improve the treatment of HBV infection.