Public vaccination programmes against hepatitis B in The Netherlands: assessing whether a targeted or a universal approach is appropriate

National decision-making for the introduction of new vaccines: A systematic review, 2010-2020

BACKGROUND

Competing priorities make using a transparent and evidence-based approach important when deciding to recommend new vaccines. We conducted a literature review to document the processes and frameworks for national decision-making on new vaccine introductions and explored which key features have evolved since 2010.

METHODS

We searched literature published on policymaking related to vaccine introduction from March 2010 to August 2020 in six databases. We screened articles for eligibility with the following exclusion criteria: non-human or hypothetical vaccines, the sole focus on economic evaluation or decision to adopt rather than policy decision-making. We employed nine broad categories of criteria from the 2012 review for categorization and abstracted data on the country, income level, vaccine, and other relevant criteria.

RESULTS

Of the 3808 unique references screened, 116 met eligibility criteria and were classified as: a) framework of vaccine adoption decision-making (27), b) studies that analyse empirical data on or examples of vaccine adoption decision-making (45), c) theoretical and empirical articles that provide insights into the vaccine policymaking process (44 + 17 already included in the previous categories). Commonly reported criteria for decision-making were the burden of disease; vaccine efficacy/effectiveness, safety; impact on health and non-health outcomes; economic evaluation and cost-effectiveness of alternative interventions. Programmatic and acceptability aspects were not as often considered. Most (50; 82%) of the 61 articles describing the process of vaccine introduction policymaking highlighted the role of country, regional, or global evidence-informed recommendations and a robust national governance as enabling factors for vaccine adoption.

CONCLUSIONS

The literature on vaccine adoption decision-making has expanded since 2010. We found that policymakers and expert advisory committee members (e.g., National Immunization Technical Advisory Group [NITAG]) increasingly value the interventions based on economic evaluations. The results of this review could guide discussions on evidence-informed immunization decision-making among country, sub-regional, and regional stakeholders.

Association between season of vaccination and antibody levels against infectious diseases

Vaccination has reduced the disease burden of vaccine-preventable diseases. However, the extent to which seasonal cycles of immunity could influence vaccine-induced immunity is not well understood. A national cross-sectional serosurveillance study performed in the Netherlands (Pienter-2) yielded data to investigate whether season of vaccination was associated with antibody responses induced by DT-IPV (diphtheria, tetanus and poliomyelitis), MMR (measles, mumps and rubella) and meningococcus C (MenC) vaccines in children. In total, 434 children met the inclusion criteria to study DT-IPV immunity, 811 for MMR and 311 for MenC. Differences in log(antibody levels) by season of vaccination were investigated with linear multivariable regression analyses. Seroconversion rates varied according to season of vaccination for rubella (90% of autumn-vaccinated children vs. 99% of winter-vaccinated had concentrations above cut-off levels). Summer-vaccinated boys showed a slower decline of tetanus antibodies (6% per month), in comparison with winter-vaccinated boys. In conclusion, season of vaccination showed little association with immunological protection. However, a number of associations were seen with a P-value of about 0.03; and adding data from a just-completed nationwide serological study might add more power to the current study. Further immunological and longitudinal investigations could help understand the mechanisms of seasonal influence in vaccine-induced responses.

Hepatitis B virus: where do we stand and what is the next step for eradication?

Hepatitis B (HB) virus (HBV) infection, which causes liver cirrhosis and hepatocellular carcinoma, is endemic worldwide. Hepatitis B vaccines became commercially available in the 1980s. The World Health Organization recommended the integration of the HB vaccine into the national immunisation programs in all countries. HBV prevention strategies are classified into three groups: (1) universal vaccination alone; (2) universal vaccination with screening of pregnant women plus HB immune globulin (HBIG) at birth; and (3) selective vaccination with screening of pregnant women plus HBIG at birth. Most low-income countries have adopted universal vaccine programs without screening of pregnant women. However, HB vaccines are not widely used in low-income countries. The Global Alliance for Vaccine and Immunization was launched in 2000, and by 2012, the global coverage of a three-dose HB vaccine had increased to 79%. The next challenges are to further increase the coverage rate, close the gap between recommendations and routine practices, approach high-risk individuals, screen and treat chronically infected individuals, and prevent breakthrough infections. To eradicate HBV infections, strenuous efforts are required to overcome socioeconomic barriers to the HB vaccine; this task is expected to take several decades to complete.

Protective effect of hepatitis B virus-active antiretroviral therapy against primary hepatitis B virus infection

OBJECTIVE

Current guidelines advise to vaccinate every hepatitis B virus (HBV)-susceptible HIV patient against HBV until sufficient antibody titers have been reached. However, in this era of combination antiretroviral therapy (cART), acute HBV infection rarely occurs in patients who lack this immune protection. We analyzed whether HBV-active cART (lamivudine, emtricitabine, tenofovir) might work as a preexposure prophylaxis (PrEP) to explain this effect.

METHODS

From our HIV cohort at the Onze Lieve Vrouwe Gasthuis hospital (N=2942), patients were selected retrospectively for negative HBV serology (HBsAg, anti-HBs and anti-HBc-negative) at cohort entry. Men who have sex with men (MSM) with a second HBV serology available were included for analysis. The incidence of anti-HBc conversion was determined and correlated with the use of HBV-active drugs. Kaplan-Meier curves and log-rank tests were used to compare HBV-free survival for MSM.

RESULTS

In total, 33 HBV infections occurred in 381 eligible MSM over a median follow-up of 2470 days (interquartile range 1146-3871.5). The incident rate per 100 patient-years of follow-up was 1.10 overall, but differed strongly dependent on the use of HBV-active drugs: 2.85/100 patient-years of follow-up in the absence of HBV-active drugs, 1.36 when only lamivudine was used, and 0.14 in the presence of tenofovir. Furthermore, HBV-free survival rate was significantly higher when HBV-active cART was used, in particular when this HBV-active cART contained tenofovir (log-rank P<0.001).

CONCLUSION

Our findings demonstrate that HBV-active cART protects against the occurrence of de-novo HBV infection, most strongly when tenofovir is used.

Targeted vaccination programme successful in reducing acute hepatitis B in men having sex with men in Amsterdam, the Netherlands

BACKGROUND & AIMS

In the Netherlands, transmission of hepatitis B virus occurs mainly within behavioural high-risk groups, such as in men who have sex with men. Therefore, a vaccination programme has targeted these high-risk groups. This study evaluates the impact of the vaccination programme targeting Amsterdam's large population of men who have sex with men from 1998 through 2011.

METHODS

We used Amsterdam data from the national database of the vaccination programme for high-risk groups (January 1, 1998 to December 31, 2011). Programme and vaccination coverage were estimated with population statistics. Incidence of acute hepatitis B was analyzed with notification data from the Amsterdam Public Health Service (1992-2011). Mathematical modelling accounting for vaccination data and trends in sexual risk behaviour was used to explore the impact of the programme.

RESULTS

At the end of 2011, programme coverage was estimated at 41% and vaccination coverage from 30% to 38%. Most participants (67%) were recruited from the outpatient department for sexually transmitted infections and outreach locations such as saunas and gay bars. Incidence of acute hepatitis B dropped sharply after 2005. The mathematical model in which those who engage most in high-risk sex are vaccinated, best explained the decline in incidence.

CONCLUSIONS

Transmission of hepatitis B virus among Amsterdam's men who have sex with men has decreased, despite ongoing high-risk sexual behaviour. Vaccination programmes targeting men who have sex with men do not require full coverage; they may be effective when those who engage most in high-risk sex are reached.

The role of implementation intention formation in promoting hepatitis B vaccination uptake among men who have sex with men

This study assessed the separate and joint effects of having a goal intention and the completeness of implementation intention formation on the likelihood of attending an appointment to obtain vaccination against the hepatitis B virus among men who have sex with men (MSM) in the Netherlands. Extending previous research, it was hypothesized that to be effective in promoting vaccination, implementation intention formation not only requires a strong goal intention, but also complete details specifying when, where and how to make an appointment to obtain hepatitis B virus vaccination among MSM. MSM at risk for hepatitis B virus ( N = 616), with strong or weak intentions to obtain hepatitis B virus vaccination, were randomly assigned to form an implementation intention or not. Completeness of implementation intentions was rated and hepatitis B virus uptake was assessed through data linkage with the joint vaccination registry of the collaborating Public Health Services. Having a strong goal intention to obtain hepatitis B virus vaccination and forming an implementation intention, each significantly and independently increased the likelihood of MSM obtaining hepatitis B virus vaccination. In addition, MSM who formed complete implementation intentions were more successful in obtaining vaccination ( p < 0.01). The formation of complete implementation intentions was promoted by strong goal intentions ( p < 0.01).

Selective hepatitis B virus vaccination has reduced hepatitis B virus transmission in the Netherlands

BACKGROUND & AIMS

In the Netherlands, a selective hepatitis B virus (HBV) vaccination programme started in 2002 for men having sex with men, drug users, commercial sex workers and heterosexuals with frequent partner changes. We assessed the programme's effectiveness to guide policy on HBV prevention.

METHODS

We analysed reports of acute HBV infection in the Netherlands between 2004 and 2010 requesting serum from patients for HBV-genome S- and C-region sequencing. We used coalescence analyses to assess genetic diversity of nonimported genotype-A cases over time.

RESULTS

1687 patients with acute HBV infection were reported between 2004 and 2010. The incidence of reported acute HBV infection decreased from 1.8 to 1.2 per 100,000 inhabitants, mostly due to a reduction in the number of cases in men who have sex with men. Men were overrepresented among cases with an unknown route of transmission, especially among genotype A2 cases mainly associated with transmission through male homosexual contact. The genetic diversity of nonimported genotype-A strains obtained from men who have sex with men decreased from 2006 onwards, suggesting HBV incidence in this group decreased.

CONCLUSIONS

The selective HBV-vaccination programme for behavioural high-risk groups very likely reduced the incidence of HBV infection in the Netherlands mainly by preventing HBV infections in men who have sex with men. A considerable proportion of cases in men who did not report risk behaviour was probably acquired through homosexual contact. Our findings support continuation of the programme, and adopting similar approaches in other countries where HBV transmission is focused in high-risk adults.

Cost-effectiveness of augmenting universal hepatitis B vaccination with immunoglobin treatment

OBJECTIVE

To compare the cost-effectiveness of hepatitis B virus (HBV) control strategies combining universal vaccination with hepatitis B immunoglobulin (HBIG) treatment for neonates of carrier mothers.

METHODS

Drawing on Taiwan's experience, we developed a decision-analytic model to estimate the clinical and economic outcomes for 4 strategies: (1) strategy V-universal vaccination; (2) strategy S-V plus screening for hepatitis B surface antigen (HBsAg) and HBIG treatment for HBsAg-positive mothers' neonates; (3) strategy E-V plus screening for hepatitis B e-antigen (HBeAg), HBIG for HBeAg-positive mothers' neonates; (4) strategy S&E-V plus screening for HBsAg then HBeAg, HBIG for all HBeAg-positive, and some HBeAg-negative/HBsAg-positive mothers' neonates.

RESULTS

Strategy S averted the most infections, followed by S&E, E, and V. In most cases, the more effective strategies were also more costly. The willingness-to-pay (WTP) above which strategy S was cost-effective rose as carrier rate declined and was <$4000 per infection averted for carrier rates >5%. The WTP below which strategy V was optimal also increased as carrier rate declined, from $1400 at 30% carrier rate to $3100 at 5% carrier rate. Strategies involving E were optimal for an intermediate range of WTP that narrowed as carrier rate declined.

CONCLUSIONS

HBIG treatment for neonates of HBsAg carrier mothers is likely to be a cost-effective addition to universal vaccination, particularly in settings with adequate health care infrastructure. Targeting HBIG to neonates of higher risk HBeAg-positive mothers may be preferred where WTP is moderate. However, in very resource-limited settings, universal vaccination alone is optimal.

Incidence of acute hepatitis B in different ethnic groups in a low-endemic country, 1992-2009: increased risk in second generation migrants

BACKGROUND

The Netherlands is a low-incidence country for acute hepatitis B (HBV) infection (1.2/100,000 in 2010), where it is typically acquired in adulthood through injecting drug use or homosexual exposure. Recently, the number of heterosexually acquired acute infections in the Netherlands has increased. Ethnicity may be a risk factor. We describe trends in the incidence of acute HBV among heterosexual adults in ethnic groups in Amsterdam from 1992 to 2009 and discuss future control of HBV in the Netherlands.

METHODS

We studied all cases of acute HBV acquired in heterosexuals aged ≥15 years in the Amsterdam region (1992-2009, n=238) by ethnic group. Incidence rates were estimated as the average number of cases per 100,000 per year. Using Poisson regression, we calculated univariable and multivariable incidence rate ratios (IRR) by ethnic group over calendar year, by age and gender.

RESULTS

The incidence in first generation migrants from HBV-endemic countries (FGM) was 4.1/100,000 showing no trend over time. Since 1999, incidence in Dutch-born cases in Amsterdam has increased by 13% annually from 0.2/100,000 in 1999 to 2.1/100,000 in 2009 (annual IRR 1.13, 95% CI:1.0-1.22). From 2004 to 2009, the incidence in native Dutch/Western in Amsterdam was 1.6/100,000 (reference for IRR), in FGM was 4.3/100,000 (IRR of 2.7, 95% CI:1.8-4.2) and in Dutch-born second generation migrants (SGM) was 3.7/100,000 (IRR:2.4, 95% CI:1.2-4.7).

CONCLUSION

Incidence of acute hepatitis B in Amsterdam in FGM and SGM is higher than in the native Dutch population. Low-endemic countries with migrant populations from HBV-endemic areas should consider offering screening and vaccination to both FGM and SGM.

Preparing for the next public debate: universal vaccination against hepatitis B

WHO have long called for universal vaccination against hepatitis B worldwide. However, in north-western Europe low incidence of the disease has fueled debate whether targeted or universal vaccination strategies are the way to go for. Careful assessment has made it clear that the extensive targeted hepatitis B vaccination programmes in the Netherlands nevertheless fail to reach a significant part of the risk groups and have not succeeded in eliminating the disease. Modelling suggests that the public health benefits obtained through targeted programmes could be augmented considerably by universal vaccination. Therefore, the Minister of Health of the Netherlands has decided to implement universal vaccination by October 2011. We illustrate the case of the Netherlands and explore lessons, which can be learnt from the vaccination programmes against HPV and influenza A/H1N1 and how to prepare for a potential public debate that might arise when implementing universal vaccination against hepatitis B.