Cost-effectiveness of the recombinant zoster vaccine in the German population aged ≥60 years old

Herpes zoster in Belgium: a new solution to an old problem

Herpes zoster (HZ) is caused by reactivation of the varicella-zoster virus. The life-time risk of developing HZ is ~ 30%. Management of HZ can be challenging due to limited efficacy of oral antivirals on pain control, and neuropathic pain that may require aggressive management. Post-herpetic neuralgia (PHN) can cause substantial pain and occurs in up to one-quarter of patients with HZ. Up to 48,000 HZ cases are estimated to occur annually in Belgium, estimated to cost almost 7 million euros in treatment. The recombinant zoster vaccine (RZV, Shingrix, GSK) was approved in Europe in 2017. In 2022, the Belgian Superior Health Council recommended vaccination with RZV for immunocompetent adults aged ≥ 60 years, and immunocompromised patients aged ≥ 16 years, including those receiving immunosuppressive therapy, in particular Janus kinase inhibitors. RZV showed high age-independent efficacy in preventing HZ infection and in clinical trials that has since been confirmed in real-world effectiveness studies. In clinical trials, protection was sustained for at least 10 years after vaccination. As of 1 November 2023, RZV is reimbursed for three immunocompromised patient groups aged ≥ 18 years: malignancy treated in the past 5 years, HIV infection, and organ or haematological stem cell transplantation or are a transplant candidate. HZ is vaccine-preventable and RZV provides a highly effective tool for HZ prevention. While reimbursement for some at-risk groups is welcomed, reimbursement currently falls well short of Superior Health Council recommendations. Adult immunisation strategies should be promoted to achieve high vaccination coverage against HZ, contributing to healthy aging in Belgium.

Cost-effectiveness of the recombinant zoster vaccine (RZV) against herpes zoster: An updated critical review

The objective of this study was to critically review the cost-effectiveness (CE) of the recombinant zoster vaccine (RZV) against herpes zoster (HZ). A literature review was conducted in PubMed, Embase, and Cochrane between January 1, 2017, and February 28, 2022, and on select public healthcare agency websites to identify and collect data from CE studies comparing RZV to zoster vaccine live (ZVL) or to no vaccination. Study characteristics, inputs, and outputs were collected. The overall CE of RZV was assessed. RZV vaccination against HZ is cost-effective in 15 out of 18 studies included in the present review. Varying incremental cost-effectiveness ratios (ICERs) observed may be associated with different assumptions on the duration of protection of RZV, as well as different combinations of structural and disease-related study (model) inputs driving the estimation of ICERs.

How large could the public health impact of introducing recombinant zoster vaccination for people aged ≥50 years in five Latin American countries be?

This study aimed to: (1) estimate the disease burden of herpes zoster (HZ) and (2) assess the potential public health impact of introducing adjuvanted recombinant zoster vaccine (RZV) compared with no vaccination in adults aged ≥50 years in Argentina, Brazil, Mexico, Chile, and Colombia using the ZOster ecoNomic Analysis (ZONA) static multicohort Markov model. The model followed individuals aged ≥50 years from administration of RZV over their remaining lifetime. Inputs were based, most often, on local data. First dose coverage was assumed to be 35%, with 75% second dose compliance. It was predicted that without RZV, there would be 23,558,675 HZ cases, 6,115,981 post-herpetic neuralgia (PHN) cases, and 7,058,779 non-PHN complications in the five countries, but introducing RZV under assumed coverage could avoid 4,583,787 (19%) HZ cases, 1,130,751 (18%) PHN cases, and 1,373,419 (19%) non-PHN complications. Also, 10427,504 (20%) doctor's office visits and 1,630,201 (19%) days of hospitalization could be averted in the three countries (Argentina, Brazil, and Mexico) with available input data. The numbers needed to be vaccinated to avoid one case of HZ were 9-10 across countries, and to avoid one case of PHN, 35-40. One-way sensitivity analyses showed that the input parameters with the largest impact on the estimated number of HZ cases avoided were first dose coverage, initial HZ incidence, and vaccine efficacy waning. In conclusion, the introduction of RZV for older adults in Latin America could greatly reduce the public health burden of HZ and reduce the related doctor visits and hospitalization days.

Cost-Effectiveness Analysis Update of the Adjuvanted Recombinant Zoster Vaccine in Japanese Older Adults

Introduction

This study aimed to update cost-effectiveness and public health impact estimates of the two-dose recombinant zoster vaccine (RZV) compared with no vaccination against herpes zoster (HZ) in the Japanese population aged 65 years. List price of the vaccine and latest RZV efficacy and waning estimates were incorporated.

Methods

A multicohort static Markov model with a cycle length of 1 year was used to follow a hypothetical cohort of one million people aged 65 years over their remaining lifetime (base case). Age-stratified vaccine efficacy and waning rates were updated on the basis of the latest clinical trial data (interim ZOE-LTFU; NCT02723773). First-dose coverage was assumed at 40%, and second-dose compliance was assumed at 95%. Costs and outcomes were discounted at 2% annually, and the incremental cost-effectiveness ratio (ICER) was calculated from payer and societal perspectives. The societal perspective considered productivity loss due to suffering HZ, or due to suffering HZ and time required for vaccination. Sensitivity analyses explored the overall uncertainties in the model. Scenario analyses for Japanese adults aged 50, 60, 70, 80, ≥ 50, and ≥ 65 years (main scenario) were conducted. An ICER below ¥5–6 million/quality-adjusted life-year (QALY) was considered cost-effective.

Results

RZV was estimated to prevent 71,423 HZ cases and 15,858 post-herpetic neuralgia (PHN) cases per million people aged 65 years compared with no vaccine in Japan. The ICER was ¥4,205,515 from a payer perspective and was most sensitive to assumptions regarding vaccine efficacy waning, proportion of patients with HZ developing PHN, and HZ incidence. From societal perspectives, ICERs were ¥3,854,192 (productivity loss from suffering HZ only) and ¥4,622,212 (productivity loss from suffering HZ and time required for vaccination). Overall, the results were considered robust under extensive sensitivity and scenario analyses.

Conclusion

Vaccination against HZ with RZV is cost-effective compared with no vaccination in Japanese adults aged 65 years.

Graphical abstract

Supplementary Information

The online version contains supplementary material available at 10.1007/s13555-022-00744-8.

Cost-Effectiveness Analysis of Herpes Zoster Vaccination in 50- to 85-Year-Old Immunocompetent Belgian Cohorts: A Comparison between No Vaccination, the Adjuvanted Subunit Vaccine, and Live-Attenuated Vaccine

BACKGROUND

A new adjuvanted subunit vaccine (HZ/su), with higher vaccine efficacy than live-attenuated vaccine (ZVL), has been licensed in Europe since March 2018. Therefore, Belgian decision-makers might need to re-assess their recommendations for vaccination against herpes zoster (HZ).

METHODS

We conducted a cost-effectiveness analysis, using a Markov decision tree, of vaccinating 50- to 85-year-old immunocompetent Belgian cohorts with no vaccination, HZ/su, ZVL, and ZVL with booster after 10 years. Due to the uncertainty in vaccine waning of HZ/su vaccine beyond 4 years, we used a logarithmic and 1-minus-exponential function to model respectively a long and short duration of protection. We used a lifetime time horizon and implemented the health care payer perspective throughout the analysis.

RESULTS

HZ/su had the greatest impact in avoiding health and economic burden. However, it would never become cost-effective at a willingness-to-pay threshold of €40,000 per quality-adjusted life year (QALY) gained at its market price set by the manufacturer in the USA. Depending on the waning function assumed for HZ/su, the price per dose needs to drop 60% or 83% such that vaccination with HZ/su, assuming respectively a long or short duration of protection, would become cost-effective in 50- and 80-year-old individuals. At €40,000 per QALY gained, ZVL or ZVL with booster was never found cost-effective compared with HZ/su, even if only administration cost was considered.

CONCLUSION

HZ/su is cost-effective in the 50-year-old age cohort at the unofficial Belgian threshold of €40,000 per QALY gained, if its price drops to €55.40 per dose. This result is, however, very sensitive to the assumed duration of protection of the vaccine, and the assumed severity and QALY loss associated with HZ and post-herpetic neuralgia (PHN).

Global herpes zoster incidence, burden of disease, and vaccine availability: a narrative review

Herpes zoster (HZ) is a neurocutaneous disease that causes significant morbidity worldwide. The disease is caused by the reactivation of the varicella-zoster virus (VZV), which leads to the development of a painful, vesicular rash and can cause complications such as post-herpetic neuralgia and vision loss. Globally, the incidence of HZ is increasing, and it incurs billions in cost annually to the healthcare system and to society through loss of productivity. With the advent of effective vaccines such as the live attenuated vaccine, Zostavax®, in 2006, and more recently the adjuvant recombinant subunit vaccine, Shingrix®, in 2017, HZ has become a preventable disease. However, access to the vaccines remains mostly limited to countries with developed economies, such as the United States and Canada. Even among countries with developed economies that license the vaccine, few have implemented HZ vaccination into their national immunization schedules due to cost-effectiveness considerations. In this review, we discuss the currently available HZ vaccines, landscape of HZ vaccine guidelines, and economic burden of disease in countries with developed and developing economies, as well as barriers and considerations in HZ vaccine access on a global scale.

Incremental net monetary benefit of herpes zoster vaccination: a systematic review and meta-analysis of cost-effectiveness evidence

OBJECTIVES

To perform a systematic review and meta-analysis to pool the incremental net benefit (INB) of each herpes zoster vaccine [i.e. Zoster Vaccine Live (ZVL) and Recombinant Zoster Vaccine (RZV)].

METHODS

We initially identified individual studies by hand-searching reference lists of the relevant systematic review articles. An updated comprehensive search was performed in Medline, Scopus, and Embase until June 2020 for additional studies. Studies were eligible if they assessed the cost-effectiveness/utility of any pair among ZVL and RZV, and no vaccine and reported economic outcomes. Details of the study characteristics, economic model inputs, costs, and outcomes were extracted. INB was calculated with monetary units adjusting for purchasing power parity for 2019 US dollars and pooled by meta-analysis.

RESULTS

A total of 37 studies were pooled for meta-analysis stratified by perspectives [i.e. societal (SP) and third-party payer (TPP)] and vaccine types. In SP, ZVL was cost-effective compared to no vaccine when vaccinated at ages of 50-59 and 70-79 years with INBs (95% CI) of $0.61 (0.37, 0.85) and $9.67 (5.20, 14.14), respectively. RZV was cost-effective for those aged 60-69 and 70-79 years with INBs of $75.61 (17.98, 133.23) and $85.01 (30.02, 140.01), respectively. In TPP, ZVL was cost-effective compared to no vaccine when vaccinated at age 70-79 years with INB of $7.57 (0.27, 14.86) and RZV was cost-effective at 60-69 years with INB $220.87 (47.80, 393.93). The cost-effectiveness of RZV was robust across a series of sensitivity analyses, but ZVL differs on different vaccination ages.

CONCLUSIONS

RZV may be cost-effective for vaccination in ages of 60-79 years for both SP and TPP perspectives, while ZVL might be cost-effective in some age groups, but results are not robust.

Long-term efficacy data for the recombinant zoster vaccine: impact on public health and cost effectiveness in Germany

The aim of the study was to update previously published public health impact and cost-effectiveness analyses of the recombinant zoster vaccine (RZV), in the German population aged ≥50 years of age (YOA), with the latest vaccine efficacy (VE) estimates against herpes zoster (HZ). The updated estimates are derived from a long-term follow-up study. A previously published multi-cohort Markov model following age cohorts over their lifetime was used. Demographic, epidemiological, cost, and utility data were based on German specific sources. Vaccine coverage was assumed to be 40%, with a second dose compliance of 70%. The estimated VE at time 0 was 98.9% (95% C.I.: 94.0–100%) with an annual waning of 1.5% (95% CI: 0.0–3.4%) for the age group 50–69 YOA. Corresponding values were 95.4% (95% C.I.: 89.7–100%) and 2.3% (95% CI: 0.3–4.4%) for the age group ≥70 YOA. It was estimated that, over the remaining lifetime since vaccination, RZV would prevent approximately 884 thousand (K), 603 K, and 538 K HZ cases in three age cohorts 50–59, 60–69, and ≥70 YOA, respectively. The number needed to vaccinate to prevent one HZ and one postherpetic neuralgia case was 6 and 36 (50–59 YOA cohort), 6 and 34 (60–69 YOA cohort), 10 and 48 (≥70 YOA cohort). The incremental cost-effectiveness ratio of vaccination ranged from €26 K/quality-adjusted life year (QALY) in 60 YOA to €35 K/QALY in 70 YOA. Due to the higher, sustained, RZV VE, improved public health and cost-effectiveness results were observed compared to previous analyses.

What is the context?

Shingles is a viral infection caused by the reactivation of the chickenpox virus. It causes a painful rash that lasts for several weeks.

The incidence and severity of shingles increase with age. In Germany alone there are approximately 400,000 new cases annually.

Vaccination can help prevent shingles.

Previous studies, based on data collected up to four years post-vaccination, estimated the number of shingles cases prevented.

What is new?

Here, we use data from the same studies followed over a longer-term to update previous analyses in the German population.

We found, based on data up to 8 years following vaccination, that:

○ In adults 50-69 years: the vaccine initially prevents 98.9% of cases, with a reduction of 1.5% each year(for example, after one year, it would prevent 97.4% of cases).

○ In adults over 70 years of age: the vaccine initially prevents 95.4% of cases, with a reduction of 2.3% each year (for example, after one year, it would prevent 93.1% of cases).

○ Vaccination would reduce the number of shingles cases by 0.9 million in a cohort of adults aged 50-59 years, 0.6 million in adults 60-69 years, and 0.5 million in adults older than 70 years, over the remainder of their lifetime.

What is the impact?

The study provides more certainty regarding results as it is based on the most complete/up to date data.

The results showed the potential of Shingrix to prevent shingles while at the same time providing good value for money.

Cost-effectiveness of varicella and herpes zoster vaccination in Sweden: An economic evaluation using a dynamic transmission model

OBJECTIVES

Comprehensive cost-effectiveness analyses of introducing varicella and/or herpes zoster vaccination in the Swedish national vaccination programme.

DESIGN

Cost-effectiveness analyses based on epidemiological results from a specifically developed transmission model.

SETTING

National vaccination programme in Sweden, over an 85- or 20-year time horizon depending on the vaccination strategy.

PARTICIPANTS

Hypothetical cohorts of people aged 12 months and 65-years at baseline.

INTERVENTIONS

Four alternative vaccination strategies; 1, not to vaccinate; 2, varicella vaccination with one dose of the live attenuated vaccine at age 12 months and a second dose at age 18 months; 3, herpes zoster vaccination with one dose of the live attenuated vaccine at 65 years of age; and 4, both vaccine against varicella and herpes zoster with the before-mentioned strategies.

MAIN OUTCOME MEASURES

Accumulated cost and quality-adjusted life years (QALY) for each strategy, and incremental cost-effectiveness ratios (ICER).

RESULTS

It would be cost-effective to vaccinate against varicella (dominant), but not to vaccinate against herpes zoster (ICER of EUR 200,000), assuming a cost-effectiveness threshold of EUR 50,000 per QALY. The incremental analysis between varicella vaccination only and the combined programme results in a cost per gained QALY of almost EUR 1.6 million.

CONCLUSIONS

The results from this study are central components for policy-relevant decision-making, and suggest that it was cost-effective to introduce varicella vaccination in Sweden, whereas herpes zoster vaccination with the live attenuated vaccine for the elderly was not cost-effective-the health effects of the latter vaccination cannot be considered reasonable in relation to its costs. Future observational and surveillance studies are needed to make reasonable predictions on how boosting affects the herpes zoster incidence in the population, and thus the cost-effectiveness of a vaccination programme against varicella. Also, the link between herpes zoster and sequelae need to be studied in more detail to include it suitably in health economic evaluations.

Patient-reported outcomes in vaccines research: relevance for decision-making

The development and demand for effective vaccines have witnessed an exponential growth over the last century. In the meantime, the vaccine market involves more knowledgeable stakeholders, with a shift in emphasis by regulatory agencies on understanding the patient perception and experience. The Food and Drug Administration's publication of the patient-reported outcomes (PRO) guidance has elevated the discipline of PROs and has resulted in a transition from clinician reports of patient outcomes to PROs. This review reports various research methods, which utilize PROs, including qualitative and quantitative research, clinical trials, and patient preference studies. With the advancement of electronic PRO data capture, additional advantages of PROs are being observed and utilized (e.g. as a trigger for clinical endpoints). We discuss uses and advantages of including PROs into the clinical trial program to improve efficiencies, clinical relevance and overall validity of the program in the vaccine field. (See Plain Language Summary).

Public Health Impact and Cost-Effectiveness of Non-live Adjuvanted Recombinant Zoster Vaccine in Canadian Adults

OBJECTIVES

In Canada, incidences of herpes zoster (HZ) and postherpetic neuralgia (PHN) are increasing, posing a significant burden on the healthcare system. This study aimed to determine the public health impact and cost effectiveness of an adjuvanted recombinant zoster vaccine (RZV) compared to no vaccination and to the live attenuated vaccine (ZVL) in Canadians aged 60 years and older.

METHODS

A multi-cohort Markov model has been adapted to the Canadian context using recent demographic and epidemiologic data. Simulations consisted of age-cohorts annually transitioning between health states. Health outcomes and costs were discounted at 1.5% per year. The perspective of the Canadian healthcare payer was adopted. A coverage of 80% for the first RZV and ZVL dose and a compliance of 75% for the second RZV dose were assumed.

RESULTS

RZV was estimated to be cost effective compared with no vaccination with an incremental cost-effectiveness ratio (ICER) of $28,360 (Canadian dollars) per quality-adjusted life-year (QALY) in persons aged ≥ 60 years, avoiding 554,504 HZ and 166,196 PHN cases. Compared with ZVL, RZV accrued more QALYs through the remaining lifetime and an increase in costs of approximately $50 million resulting in an average ICER of $2396. Results were robust under deterministic and probabilistic sensitivity analyses. HZ incidence rate and persistence of vaccine efficacy had the largest impact on cost effectiveness.

CONCLUSIONS

The cost-utility analysis suggested that RZV would be cost effective in the Canadian population compared with no vaccination and vaccination with ZVL at a willingness-to-pay threshold of $50,000.

The potential public health impact of Herpes Zoster vaccination in the 65 years of age cohort in Italy

Herpes Zoster (HZ) presents a considerable public health burden in Italy among people aged ≥50 years. This study aimed to assess the clinical and economic impact of HZ vaccination in the 65 years of age (YOA) cohort in Italy, by comparing the new Adjuvanted Recombinant Zoster Vaccine (RZV) with the currently available Zoster Vaccine Live (ZVL). A static Markov model was developed to follow all 65 YOA subjects from the year of vaccination over their lifetime by comparing three different HZ vaccination strategies: no vaccination, vaccination with ZVL and vaccination with RZV. In the base-case scenario, three 65 YOA cohorts were assumed to be vaccinated within three years, with a vaccine coverage rate of 20%, 35% and 50% at Year 1, 2 and 3 respectively, as recommended by the National Immunization Plan. The three 65 YOA Italian cohorts accounted altogether for 2,290,340 individuals. Of these, it was assumed that 564,178 subjects could be vaccinated with either RZV or ZVL in three years. The vaccination with RZV could prevent an additional total number of 35,834 HZ and 8,131 postherpetic neuralgia (PHN) cases over ZVL, leading to additional total savings of €12.4 million for the national healthcare and social systems. The introduction of RZV can be expected to have higher impact on the burden of HZ disease in the 65 YOA cohort in Italy. The avoided HZ and PHN cases can lead to an associated reduction in economic burden to the healthcare and social systems.

Varicella zoster virus vaccines: an update

Varicella zoster virus (VZV) is the etiological agent of varicella, a highly infectious, self-limiting disease with serious complications. The decline in cell-mediated immunity (CMI) that occurs with aging or immunodepression causes a reactivation of the latent VZV as herpes zoster (HZ). Prevention of VZV through varicella vaccination strategies allows to avoid the primary infection in newborns and susceptible subjects. Available monovalent and combined VZV vaccines are effective, safe and generally well tolerated. Universal varicella vaccination has significantly impacted on incidence, complications and deaths related to this disease. Prevention of HZ through vaccination is a priority to avoid the significant burden of its incidence and complications. Currently two HZ vaccines are available. The recombinant zoster vaccine (RZV), approved by the FDA in 2017 and Zoster Vaccine Live (ZVL) licensed in the United States by the FDA in 2006. The advisory committee on immunization practices (ACIP) preferentially recommends RZV. ZVL remains an option for prevention of HZ in immunocompetent adults aged ≥60 years, although the CMI tends to wane a few years after vaccination.

Cost-Effectiveness of the Adjuvant Recombinant Zoster Vaccine in Japanese Adults Aged 65 Years and Older

INTRODUCTION

The incidence of herpes zoster (HZ) rises steeply after the age of 50 years and the number of HZ cases and complications such as postherpetic neuralgia (PHN) is predicted to increase because of the ageing population. The objective of this study was to estimate the cost-effectiveness of recombinant zoster vaccine (RZV) compared with no vaccine for the Japanese population aged ≥ 65 years.

METHODS

A multi-cohort static Markov model with a cycle length of 1 year was used to follow a hypothetical cohort of 1 million people aged ≥ 65 years over their remaining lifetime. Vaccination at ≥ 65 years was used in alignment with the influenza and pneumococcal vaccines recommended from 65 years. Japan-specific data inputs for the model were obtained from local data sources. Age-stratified vaccine efficacy and waning rates were based on published clinical trial data. In the base-case analysis, vaccine coverage was assumed to be 40% with a second dose compliance of 95%. Costs and outcomes were discounted at 2% annually and the incremental cost-effectiveness ratio (ICER) was calculated from both a payer's and the societal perspective. Sensitivity analyses were carried out to explore the overall uncertainty in the model.

RESULTS

Vaccination with RZV was projected to prevent 48,943 HZ cases and 12,136 PHN cases per million people aged ≥ 65 years compared with no vaccination. The incremental costs and quality-adjusted life years (QALYs) gained were ¥9.99 billion and 2314 QALYs from a payer's perspective and ¥9.34 billion and 2314 QALYs from a societal perspective. The resulting ICERs were approximately ¥4,320,000 and ¥4,040,000 per QALY gained from a payer's and the societal perspective, respectively. The ICER remained below a willingness-to-pay threshold of ¥5,000,000 for most sensitivity analyses carried out.

CONCLUSION

Vaccination against HZ with RZV would be cost-effective compared with no vaccination for the Japanese population aged ≥ 65 years.

TRIAL REGISTRATION

GSK study identifier: HO-16-17837.

FUNDING

GlaxoSmithKline Biologicals SA.

Cost-effectiveness of vaccination of immunocompetent older adults against herpes zoster in the Netherlands: a comparison between the adjuvanted subunit and live-attenuated vaccines

BACKGROUND

The newly registered adjuvanted herpes zoster subunit vaccine (HZ/su) has a higher efficacy than the available live-attenuated vaccine (ZVL). National decision-makers soon need to decide whether to introduce HZ/su or to prefer HZ/su above ZVL.

METHODS

Using a Markov model with a decision tree, we conducted a cost-effectiveness analysis of vaccination with HZ/su (two doses within 2 months) or zoster vaccine live (ZVL) (single dose, or single dose with a booster after 10 years) for cohorts of 50-, 60-, 70- or 80-year-olds in the Netherlands. The model was parameterized using vaccine efficacy data from randomized clinical trials and up-to-date incidence, costs and health-related quality of life data from national datasets. We used a time horizon of 15 years, and the analysis was conducted from the societal perspective.

RESULTS

At a coverage of 50%, vaccination with two doses of HZ/su was estimated to prevent 4335 to 10,896 HZ cases, depending on the cohort age. In comparison, this reduction was estimated at 400-4877 for ZVL and 427-6466 for ZVL with a booster. The maximum vaccine cost per series of HZ/su to remain cost-effective to a willingness-to-pay threshold of €20,000 per quality-adjusted life year (QALY) gained ranged from €109.09 for 70-year-olds to €63.68 for 50-year-olds. The cost-effectiveness of ZVL changed considerably by age, with corresponding maximum vaccine cost per dose ranging from €51.37 for 60-year-olds to €0.73 for 80-year-olds. Adding a ZVL booster after 10 years would require a substantial reduction of the maximum cost per dose to remain cost-effective as compared to ZVL single dose. Sensitivity analyses on the vaccine cost demonstrated that there were scenarios in which vaccination with either HZ/su (two doses), ZVL single dose or ZVL + booster could be the most cost-effective strategy.

CONCLUSIONS

A strategy with two doses of HZ/su was superior in reducing the burden of HZ as compared to a single dose or single dose + booster of ZVL. Both vaccines could potentially be cost-effective to a conventional Dutch willingness-to-pay threshold for preventive interventions. However, whether HZ/su or ZVL would be the most cost-effective alternative depends largely on the vaccine cost.