Cost-Effectiveness of Herpes Zoster Vaccination: A Systematic Review

Herpes zoster vaccination coverage and factors associated among adults aged 40 and older in China: A population-based survey

OBJECTIVES

Herpes zoster (HZ) is a significant public health issue in China, especially with an aging population and rising incidence. While vaccination effectively prevents HZ and its complications, national data on HZ vaccine (HZV) coverage and associated factors in China are limited.

METHODS

We conducted a nationwide survey across 25 provinces in mainland China, including 14,315 participants aged over 40 years, to estimate HZV uptake and associated factors among adults aged 40 years and older. Multivariate logistic regression was used to assess characteristics linked to vaccination, and we analysed vaccine types and dose completion rates.

RESULTS

The HZV uptake rate was 0.79 %. Vaccination was more likely among individuals with middle school education and higher household income. Most vaccinated individuals received the zoster vaccine live (ZVL) rather than the recombinant zoster vaccine (RZV), and nearly half completed two doses.

CONCLUSIONS

HZV coverage in China is low, underscoring the need for targeted public health strategies to improve vaccine accessibility and awareness, particularly among at-risk groups, to reduce HZ-related burdens.

The barriers and facilitators of herpes zoster vaccination intentions of urban residents in China: a qualitative study

BACKGROUND

In an aging society, herpes zoster (HZ) increases the health burden on infected patients. While quantitative studies point to a lack of willingness to accept the HZ vaccine in China, there is limited number of studies with in-depth qualitative analysis on HZ vaccination intention. This study undertakes a qualitive study method to identify the barriers and facilitators behind urban residents' HZ vaccination intention in three China cities, and contributes towards some targeted vaccination promotion suggestions to China and other LMICs with similar low coverage of HZ vaccination.

METHODS

We conducted 12 focus group discussions in three cities of China. In each discussion we recruited 3 to 6 participants aged 20 and older to catch the views on the HZ vaccine from residents with a wider age range. Participants were recruited by purposive sampling techniques. Guided by the health belief model, thematic analysis was used to group participants' HZ vaccine attitudes and to identify the barriers and facilitators to HZ vaccination.

RESULTS

The attitude of 59 participants participating in the focus group discussions showed a low-level acceptability of the HZ vaccine with only 27.1% (16/59) displaying a willingness to HZ vaccine uptake. The barriers to HZ vaccination included limited or incorrect conception on HZ prevalence, risk factors, susceptibility, symptoms, prevention and treatment methods, and the high cost of the HZ vaccine. Perceived vulnerability to HZ, fear of HZ pain and individuals' financial capacity were the strongest facilitators to HZ vaccination. In addition, it was found that advocacy of HZ vaccination by health professionals or government financial subsidies to HZ vaccination, could attenuate the above barriers to HZ vaccine uptake.

CONCLUSIONS

Our study revealed a series of barriers and facilitators of HZ vaccination intention. We recommend HZ education and advocacy by health workers and government health officials to address the limited HZ knowledge and HZ misconceptions, and the government (or health insurance providers) to pay or subsidize the high costs of HZ vaccination to increase the HZ vaccination rate.

National trends and disparities in herpes zoster vaccination among US older adults with chronic obstructive pulmonary disease, 2008 to 2022

BACKGROUND

Chronic obstructive pulmonary disease (COPD) is a risk factor for herpes zoster. Vaccination can prevent or attenuate herpes zoster and its related complications. However, evidence regarding vaccine uptake among patients with COPD is limited. Therefore, this study aimed to evaluate trends in herpes zoster vaccination and characteristics associated with vaccination among US older adults with COPD.

METHODS

Data from the 2008 to 2022 National Health Interview Survey were used. Participants aged ≥50 years were included. Joinpoint regression analysis was performed to analyze trends in herpes zoster vaccination. A multivariable logistic regression model was used to identify factors associated with vaccination.

RESULTS

From 2008 to 2022, an increasing trend in herpes zoster vaccination was observed (average annual percent change = 15.10, P < .01). This increasing trend was also observed when stratified by age groups. Disparities in vaccination were found across several factors, including age, sex, race or ethnicity, region, educational level, health insurance, income, smoking status, perceived health status, and flu and pneumococcal vaccination.

CONCLUSIONS

There has been an upward trend in herpes zoster vaccination over the past 15 years among older adults with COPD. Disparities across several characteristics existed, underscoring the necessity for targeted policies and interventions to promote equity in vaccination.

Preferences and Willingness to Pay for Herpes Zoster Vaccination Among Chinese Adults: Discrete Choice Experiment

BACKGROUND

The incidence of herpes zoster (HZ) is rapidly increasing, causing both clinical and economic burdens in China. Very little is known about Chinese residents' HZ vaccine preferences and willingness to pay (WTP) for each vaccination attribute.

OBJECTIVE

This study aims to elicit the preferences of Chinese urban adults (aged 25 years or older) regarding HZ vaccination programs and to calculate WTP for each vaccination attribute.

METHODS

In this study, we interviewed 2864 residents in 9 cities in China. A discrete choice experiment was conducted to investigate the residents' preferences for HZ vaccination and to predict the uptake rate for different vaccine scenarios. A mixed logit model was used to estimate the preferences and WTP for each attribute. Seven attributes with different levels were included in the experiment, and we divided the coefficients of other attributes by the coefficient of price to measure WTP.

RESULTS

Vaccine effectiveness, protection duration, risk of side effects, place of origin, and cost were proven to influence Chinese adults' preferences for HZ vaccination. The effectiveness of the HZ vaccine was the attribute that had the most predominant impact on residents' preferences, followed by protection duration. The residents were willing to pay CN ¥974 (US $145) to increase the vaccine effectiveness from 45% to 90%, and they would barely pay to exchange the vaccination schedule from 2 doses to 1 dose. It is suggested that the expected uptake could be promoted the most (by 20.84%) with an increase in the protection rate from 45% to 90%.

CONCLUSIONS

Chinese urban adults made trade-offs between vaccine effectiveness, protection duration, place of origin, side effects, and cost of HZ vaccination. Vaccine effectiveness was the most important characteristic. The residents have the highest WTP (CN ¥974; US $145) for enhancing the effectiveness of vaccines. To maximize HZ vaccine uptake, health authorities should promote vaccine effectiveness.

Cost-Effectiveness Analysis of Herpes Zoster Vaccination in a Chinese Population: Recombinant Subunit Vaccine versus Live Attenuated Vaccine

BACKGROUND

Currently, the recombinant subunit vaccine and live attenuated vaccine in the prevention of herpes zoster are approved for marketing in China. This study aims to evaluate the cost-effectiveness of the recombinant subunit vaccine and the live attenuated vaccine in the Chinese population.

METHODS

A decision tree-Markov analysis model was utilized to estimate expected costs and quality-adjusted life years (QALYs), comparing the lifetime cost-effectiveness of vaccination with the recombinant subunit vaccine (London, United Kingdom, Shingrix, GSK) to that of the live attenuated vaccine (Changchun, China, Ganwei, Changchun Bcht) in the Chinese population, with the primary outcome measure being the incremental cost-effectiveness ratio (ICER).

RESULTS

In the base-case analysis, the ICERs for the recombinant subunit vaccine ranged by age from USD 3428 to USD 5743 per QALY, while the ICERs for the live attenuated vaccine ranged from USD 4017 to USD 18,254 per QALY, compared with no vaccination. Among all age groups, the category of 60 to 69 years was the optimal age for vaccination. The results were most sensitive to changes in herpes zoster incidence, vaccine efficacy, and discount rate. Even with a two-dose compliance rate of 20% for the recombinant subunit vaccine, vaccination remained cost-effective. ZVL would need to reduce costs by at least 12.2% compared to RZV to have a cost-effectiveness advantage.

CONCLUSIONS

The recombinant subunit vaccine and the live attenuated vaccine were both cost-effective in the Chinese population, but, relatively, the recombinant subunit vaccine had a greater advantage in disease prevention and cost-effectiveness in all age groups above 50 years.

Turning the Tide against Herpes Zoster in Rheumatoid Arthritis Patients Treated with JAK Inhibitors

Objectives: This study aimed to evaluate the incidence of Herpes Zoster (HZ) in patients with rheumatoid arthritis (RA) treated with Janus kinase inhibitors (JAKi), and to predict potential risk factors for HZ development. Methods: We retrospectively analysed medical records from RA patients at our rheumatology unit who met the 2010 ACR/EULAR criteria for RA and were receiving JAKi. The incidence and course of HZ were assessed through chart review and supplementary phone interviews. Results: A total of 198 JAKi-treated patients were monitored for an average of 18.5 months. Nine subjects experienced HZ, resulting in an incidence of 2.95 per 100 patient-years. No demographic or treatment-related differences were found among patients who developed HZ and those who did not. Disease duration (OR: 1.06, 95% CI: 1.01-1.12), time on JAKi treatment (OR: 1.04, 95% CI: 1.009-1.073), higher disease activity at JAKi initiation (OR: 4.16, 95% CI: 1.07-16.17), and at 3-month follow-up (OR: 6.0, 95% CI: 1.35-26.60) were identified as predictors of HZ occurrence. Thirty-six patients received vaccination against HZ, and none reported adverse reactions or flare-ups during a mean follow-up of 9.6 months. Conclusions: The incidence of HZ aligns with published data, suggesting that disease and treatment duration, as well as disease activity, are significant predictors of HZ in RA patients on JAKi therapy. Vaccination against HZ proved to be safe and effective, underscoring its potential protective value in this patient population.

Differential Utility Losses in Herpes Zoster Cases Between Vaccinated and Unvaccinated Subjects: A Meta-analysis of Three Clinical Trials

BACKGROUND AND OBJECTIVE

Recombinant zoster vaccine (RZV) is approved in adults for the prevention of herpes zoster. The effect of RZV in moderating the severity of breakthrough cases of herpes zoster has been noted but not explicitly quantified before. In this study, a meta-analysis was undertaken to estimate differential utility losses between unvaccinated (Placebo) and vaccinated (RZV) subjects in breakthrough cases of herpes zoster from three RZV clinical trials.

METHODS

Differential utility losses between the two groups were estimated in units of quality-adjusted life-years (QALYs), leveraging aggregate patient data from the ZOE-50 (NCT01165177), ZOE-70 (NCT01165229), and ZOE-HSCT (NCT01610414) clinical trials. Differential utility losses and the ratio of mean utility losses were analyzed using random-effects and fixed-effects meta-regression models.

RESULTS

The mean QALY loss differences between the unvaccinated (Placebo) and vaccinated (RZV) groups were 0.008, 0.004, and 0.011 in the ZOE-50, ZOE-70, and ZOE-HSCT studies, respectively, yielding an overall estimated difference of 0.007 (95% confidence interval 0.002-0.012) QALYs. Quality-adjusted life-year loss in the vaccinated group was estimated to be 35.5% of the value in the placebo group. A sensitivity analysis estimated an overall difference of 0.005 (95% confidence interval 0.001-0.009) QALYs, corresponding to 48.6% of the QALY loss value in the placebo group.

CONCLUSIONS

Recombinant zoster vaccine is effective in alleviating disease severity in breakthrough cases of herpes zoster. The results may be useful in distinguishing QALY losses between vaccinated and unvaccinated cohorts in health economics studies, particularly cost-effectiveness analyses.

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.

Willingness to vaccinate against herpes zoster in Chinese urban population: a mixed-methods study

OBJECTIVE

Although the herpes zoster vaccine has been available in mainland China since June 2020, residents' knowledge of herpes zoster and the herpes zoster vaccine is poor, and vaccination rates are low, especially among the elderly, who are at high risk for herpes zoster. This study assessed willingness to be vaccinated against herpes zoster and factors associated with vaccination among urban residents in China.

METHODS

A mixed-methods study was conducted in community health centres from August 2022 to September 2022. We used convenience sampling to select 2864 residents from 9 Chinese cities for the quantitative study and 67 adults for the qualitative study. A structured questionnaire was used for the quantitative study, and data were collected through face-to-face interviews. Multinomial logistic regression was used to analyse factors associated with willingness to vaccinate. Qualitative data were analysed using thematic analysis of barriers to herpes zoster vaccination.

RESULTS

A total of 2864 eligible respondents were included in the study. Of these, 42.67% intended to receive the herpes zoster vaccine, 21.44% refused and 35.89% were hesitant. The results of the quantitative and qualitative analyses showed that the factors associated with respondents' willingness to be vaccinated against herpes zoster included: personal characteristics such as gender, age and income; knowledge and attitudes about herpes zoster and the vaccine; vaccine characteristics such as efficacy, safety and price; and other factors such as pain tolerance and accessibility to vaccination.

CONCLUSION

The low willingness to vaccinate, especially among the elderly, is mainly related to their poor knowledge and negative attitude towards the infection and vaccination. Therefore, health education about herpes zoster, immunisation promotion, and improvement of accessibility and affordability would be valuable in China.

[Vaccination against the herpes zoster virus]

OBJECTIVE

To review the latest published evidence on the vaccine used in our country against the herpes zoster virus, breaking down the results according to the efficacy, efficiency, effectiveness and safety of the vaccine. Include the current recommendations for vaccination.

DESIGN

Secondary review. Descriptive qualitative review. Review using the search term "herpes zoster vaccine" and "Adjuvanted recombinant Herpes Zoster subunit vaccine". Retrospective observational study.

DATA SOURCES

Embase, Medline and Google Scholar. Selection of studies Search criterion with the terms "Shingrix vaccine" and "Adjuvanted Herpes Zoster Subunit Vaccine". Search period 2013-2023. Studies classified as clinical trials or randomized clinical trials were selected. 21 published studies were evaluated. There were no exclusions.

RESULTS

The evaluated studies were found to be coherent and in all of them efficacy in adult individuals in preventing viral reactivation and in preventing complications was higher than 80%. The effectiveness of the vaccine after two doses was also higher than 80%. Cost-effectiveness studies were always favourable in adults, immunodepressed patients and individuals with chronic pathology. The safety of the vaccine was evaluated in the pivotal studies and in the post-commercialization studies that were undertaken (although there were few of the latter due to the short period of time studied). The safety profile of the vaccine is very high and in the case of severe adverse effects, their frequency was similar to that of a placebo.

CONCLUSIONS

We have a safe and effective vaccine against the herpes zoster virus that allows us to protect the most vulnerable population groups against this virus.

Explore the optimal timing for administering the second dose of the varicella vaccine in China

The prevalence of varicella in China has been increasing annually, with a relatively high incidence rate of breakthrough cases. Administering two doses of the varicella vaccine (Varv) proves to be the most effective measure. The objective of this study is to assess the immunogenicity of two doses of the Varv at varying intervals and explore the optimal timing for administering the second dose of the Varv. Utilizing a prospective cohort study design, the quantification of varicella immunoglobulin G (IgG) antibodies' geometric mean concentrations (GMC) is conducted through glycoprotein-based enzyme-linked immunosorbent assay (gpELISA). A total of 903 infants were included in the per-protocol population. After completing the first dose of the Varv, the GMC of antibody after 1 month (Group A) was 463.8 (447.6-480.1) mIU/mL. There was a statistically significant difference in GMC and seroconversion rates among the groups (B/C/D) that received the second dose of the Varv (p < 0.05). Multiple comparisons revealed that the group with a 3-year interval between the two vaccine doses had a higher GMC of 665.2 (622.6-707.8) mIU/mL compared to the group with a 1-year interval of 611.1 (577.1-645.3) mIU/mL and the group with a 5-year interval of 564.7 (540.1-589.4) mIU/mL. To effectively prevent and control the varicella epidemic in Jiangsu Province, two dose Varv vaccination is recommended, the optimal time point for the second dose Varv is 3 years after the first vaccination.

Willingness to Vaccinate Against Herpes Zoster and Its Associated Factors Across WHO Regions: Global Systematic Review and Meta-Analysis

BACKGROUND

A life-course immunization approach would enhance the quality of life across all age groups and improve societal well-being. The herpes zoster (HZ) vaccine is highly recommended for older adults to prevent HZ infection and related complications. The proportions of willingness to receive the HZ vaccine varies across countries, and various kinds of factors, including sociodemographics and individual perceptions, influence the willingness to vaccinate.

OBJECTIVE

We aim to estimate the HZ vaccination willingness rate and identify factors associated with vaccine uptake willingness across all World Health Organization (WHO) regions.

METHODS

A global systematic search was performed on PubMed, Web of Science, and the Cochrane Library for all papers related to the HZ vaccine published until June 20, 2022. Study characteristics were extracted for each included study. Using double arcsine transformation, vaccination willingness rates with 95% CIs were pooled and reported. The willingness rate and associated factors were analyzed by geographical context. Associated factors were also summarized based on Health Belief Model (HBM) constructs.

RESULTS

Of the 26,942 identified records, 13 (0.05%) papers were included, covering 14,066 individuals from 8 countries in 4 WHO regions (Eastern Mediterranean Region, European Region, Region of the Americas, and Western Pacific Region). The pooled vaccination willingness rate was 55.74% (95% CI 40.85%-70.13%). Of adults aged ≥50 years, 56.06% were willing to receive the HZ vaccine. After receiving health care workers' (HCWs) recommendations, 75.19% of individuals were willing to get the HZ vaccine; without HCWs' recommendations, the willingness rate was only 49.39%. The willingness rate was more than 70% in the Eastern Mediterranean Region and approximately 55% in the Western Pacific Region. The willingness rate was the highest in the United Arab Emirates and the lowest in China and the United Kingdom. The perception of HZ severity and susceptibility was positively associated with vaccination willingness. The perceived barriers to vaccination willingness (main reasons for unwillingness) included low trust in the effectiveness of the HZ vaccine, concerns about safety, financial concerns, and being unaware of the HZ vaccine's availability. Older individuals, those having lower education, or those having lower income levels were less likely to willing to be vaccinated.

CONCLUSIONS

Only 1 in 2 individuals showed a willingness to be vaccinated against HZ. The willingness rate was the highest in the Eastern Mediterranean Region. Our findings show the critical role HCWs play in promoting HZ vaccination. Monitoring HZ vaccination willingness is necessary to inform public health decision-making. These findings provide critical insights for designing future life-course immunization programs.

Cost-Effectiveness Analysis of Vaccination With Recombinant Zoster Vaccine Among Hematopoietic Cell Transplant Recipients and Persons With Other Immunocompromising Conditions Aged 19 to 49 Years

OBJECTIVES

This study aimed to estimate the cost-effectiveness of the use of recombinant zoster vaccine (RZV) (Shingrix), which protects against herpes zoster (HZ), among immunocompromised adults aged 19 to 49 years, as a contribution to deliberations of the Advisory Committee on Immunization Practices.

METHODS

Hematopoietic cell transplant (HCT) recipients experience a high incidence of HZ, and the efficacy of RZV in preventing HZ has been studied in clinical trials. The cost-effectiveness model calculated incremental cost-effectiveness ratios that compared vaccination with RZV with a no vaccination strategy among adults aged 19 to 49 years. Costs and outcomes were calculated until age 50 years using the healthcare sector perspective and summarized as cost per quality-adjusted life-year (QALY) gained. The base case represents HCT recipients, with scenario analyses representing persons with other immunocompromising conditions, including hematologic malignancies, human immunodeficiency virus, and autoimmune and inflammatory conditions. Uncertainty was investigated using univariate, multivariate, and probabilistic sensitivity analyses.

RESULTS

Base-case results indicated vaccination with RZV would avert approximately 35% of HZ episodes and complications, while saving approximately 11% of net costs. Compared with no vaccination, vaccination of HCT recipients with RZV generated cost-savings (ie, lower costs and improved health) in the base case and in 81% of simulations in the probabilistic analysis. In scenario analyses, vaccination cost US dollar ($) 9500/QALY among patients with hematologic malignancies, $79 000/QALY among persons living with human immunodeficiency virus, and $208 000/QALY among persons with selected autoimmune and inflammatory conditions.

CONCLUSIONS

Generally favorable economic estimates supported recommendations for vaccination of immunocompromised adults with RZV to prevent episodes of HZ and related complications.

Country score tool to assess readiness and guide evidence generation of immunization programs in aging adults in Europe

Objectives

Delaying of policies for immunization of aging adults, low vaccine uptake, and the lack of supportive evidence at the national level could diminish the value in health and economics of such programs. This study aims to develop a "country score tool" to assess readiness and to facilitate evidence generation for aging adult immunization programs in Europe, and examine the comprehensiveness, relevance, acceptability, and feasibility of the tool.

Methods

The tool was developed in two phases. First, a modified Delphi process was used to construct the tool. The process included a literature review, stakeholder consultations, and a three-round Delphi study. The Delphi panel included researchers, supra-national and national decision-makers of immunization programs recruited from five countries, using snowball sampling method. The consensus was predefined at the agreement rate of 70%. Pilot testing of the tool was conducted in the Netherlands, Germany, Serbia, and Hungary involving researchers in the field of health technology assessment. After assessing the countries' readiness, researchers evaluated four features, namely comprehensiveness, relevance, acceptability, and feasibility of the tool via an online survey that included 5-scale Likert questions. The percentages of affirmative answers including "agree" and "totally agree" choices were presented.

Results

The review identified 16 tools and frameworks that formed the first version of our tool with 14 items. Eight experts were involved in the Delphi panel. Through three Delphi rounds, four items were added, one was dropped, and all others were amended. The consensus was achieved on the tool with 17 items divided into decision-making and implementation parts. Each item has a guiding question, corresponding to explanations and rationales to inform assessment with readiness scores. Eight researchers completed the pilot testing. The tool was rated as comprehensive (75%), relevant (100%), acceptable (75%), and feasible (88%) by participants.

Conclusion

Through a thorough and transparent process, a country score tool was developed helping to identify strengths, weaknesses, and evidential requirements for decision-making and implementation of immunization programs of aging adults. The tool is relevant for different European contexts and shows good comprehensiveness, acceptability, and feasibility.

Longitudinal changes in cell-mediated immunity after varicella-zoster virus skin test in the general population; Shozu Herpes Zoster Study: SHEZ study

Varicella-zoster virus-specific cell-mediated immunity has been associated with the onset and severity of herpes zoster (HZ), and the administration of the HZ vaccine enhanced the immunity. However, limited data is available on the duration of cell-mediated immunity enhancement by soluble antigen of varicella-zoster virus (VZV) skin test. A prospective, community-based cohort study was conducted in Shozu County, Kagawa Prefecture, Japan. Repeated VZV skin tests containing inactivated VZV antigen and blood tests were performed on 365 subjects aged 60 years and older at baseline, 1, 2, and 3 years later. The differential immunity indices of VZV over time for cell-mediated and humoral immunity were evaluated. VZV skin test reaction and ELISpot counts increased significantly at 1, 2, and 3 years later compared to the baseline. However, humoral immunity indices did not change materially over time. Soluble antigen by VZV skin test enhanced VZV-specific cell-mediated immunity, and it persisted for at least 1 year. In addition, the inoculation with inactivated antigens every year by VZV skin test continued to enhance VZV-specific cell-mediated immunity after 2 and 3 years.

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.

Cost and health impact analysis of herpes zoster vaccination in Norway

BACKGROUND

A decision analytic model was developed to estimate the cost-effectiveness of a national vaccination program against herpes zoster in Norway.

METHODS

The model analyzed six vaccination scenarios that included the live-attenuated zoster vaccine under different target ages of vaccination (60, 65, and 70 years) compared with no vaccination. A catch-up program implemented in the first year of the vaccination was included in three of the scenarios. The model followed the population of Norway over a 40-year time horizon to estimate costs and outcomes associated with vaccination. Immunization costs, costs related to herpes zoster (both healthcare sector and non-healthcare sector), the quality of life gains due to avoided cases of herpes zoster, and quality-of-life losses due to vaccine-related adverse events were estimated.

RESULTS AND CONCLUSIONS

A national vaccination program would result in reduction of the number of herpes zoster cases and decreased burden of illness. Vaccinating adults at 65 years of age with catch-up up to 70 years in the first year of the program was the most cost-effective strategy with the incremental cost per quality-adjusted life-year gained at NOK (Norwegian Krone) 245,459 from the societal perspective and NOK 248,637 from the health care system perspective.

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.

Vaccination for quality of life: herpes-zoster vaccines

Current vaccination policy in most high-income countries aims to counteract the decline in cell-mediated immunity to varicella zoster virus that occurs with advancing age or immunosuppression. The aim of this review was to describe the burden of illness associated with herpes zoster (HZ) and post-herpetic neuralgia (PHN) risks and their impact on the social and common life in infected people. The effectiveness/efficacy and cost effectiveness of the immunization strategy will be presented through the review of the literature relevant to the live attenuated HZ vaccine (ZLV) licensed in 2006 and the recombinant HZ vaccine (RZV). The latter has very recently been approved to protect aged people aged ≥ 50 years against HZ morbidity including its complications, and associated health-care costs. Finally, this review also provides data with respect of precautions of using and safety of ZVL and RVZ.

Patterns of prescription, hospitalizations and costs of herpes zoster in patients at risk, from a large Italian claims database

Purpose

This observational study aimed to investigate the incidence of herpes zoster (HZ) among at-risk subjects aged ≥50 years, characterize them and assess annual healthcare utilization and costs from the Italian National Health System (NHS) perspective.

Methods

Records of reimbursed drug prescriptions, hospitalizations and outpatient specialist care from the Fondazione ReS database were linked to identify patients aged ≥50 years at HZ risk (i.e. cardiovascular disease/chronic obstructive pulmonary disease/diabetes/immunosuppression, according to the Italian National Vaccine Prevention Plan - PNPV 2017-2019) in 2013. New HZ events (incidence per 1,000) were researched in 2 years, and subjects with HZ in the previous year were excluded. Antiviral and pain therapy consumptions, hospitalizations for HZ and costs paid by NHS were assessed annually.

Results

From 12,562,609 inhabitants in 2013, a total of 1,004,705 patients (18.5% aged ≥50 years) at risk without a previous event were selected. The 2-year incidence of HZ was 5.9 per 1,000 (mean age 74 ± 10 years; 54.3% female). Patients aged 80-89 (7.2 per 1,000), females (6.7 per 1,000) and immunosuppressed subjects (6.9 per 1,000) had the highest incidence rates. One year after the new HZ episode, 82.2% were treated with specific antivirals (79.3% brivudine), generating an annual average cost/treated of €106; 8.0% were hospitalized for HZ, with an average cost/hospitalized of €3,927; the overall mean cost/incident patient was €402.

Conclusions

This analysis provided HZ incidence in subjects aged ≥50 years considered at risk by the PNPV and its burden from the NHS perspective. Our findings can help health governance to improve clinical decisions and economic positioning concerning zoster vaccine plan.

A global agenda for older adult immunization in the COVID-19 era: A roadmap for action

Given our global interconnectedness, the COVID-19 pandemic highlights the urgency of building a global system that can support both routine and pandemic/epidemic adult immunization. As such, a framework to recommend vaccines and build robust platforms to deliver them to protect the rapidly expanding demographic of older adults is needed. Adult immunization as a strategy has the broad potential to preserve and improve medical, social, and economic outcomes, including maintaining functional ability that benefits older adults, their families, communities, and countries. While we will soon have multiple vaccines against COVID-19, we must recognize that we already have a variety of vaccines against other pathogens that can keep adults healthier. They can prevent simultaneous co-infection with COVID-19, and may favorably impact- the outcome of a COVID-19 illness. Further, administering a vaccine against COVID-19 requires planning now to determine delivery strategies impacting how older adults will be immunized in a timely manner. A group of international experts with various backgrounds from health and aging disciplines met to discuss the evidence case for adult immunization and crucial knowledge gaps that must be filled in order to implement effective policies and programs for older adult immunization. This group, coming together as the International Council on Adult Immunization (ICAI), outlined a high-level roadmap to catalyze action, provide policy guidance, and envision a global adult immunization platform that can be adapted by countries to fit their local contexts. Further meetings centered around the value of adult immunization, particularly in the context of COVID-19. There was agreement that programs to deliver existing influenza, pneumococcal, herpes zoster vaccines, and future COVID-19 vaccines to over a billion older adults who are at substantially higher risk of death and disability due to vaccine-preventable diseases are more urgent than ever before. Here we present a proposed framework for delivering routine and pandemic vaccines. We call upon the global community and governments to prioritize action for integrating robust adult immunization programs into the public health agenda.

Outpatient healthcare utilization and prescribing patterns for herpes zoster in United States adults

Little is known about health resource utilization and treatment patterns for herpes zoster (HZV) after the introduction of HZV virus vaccination. The objective of this study is to characterize trends in HZV utilization, racial disparities, and treatment patterns in the United States. Data from the 1993-2015 National Ambulatory Medical Care Survey were analyzed, including 15,400,000 weighted primary acute HZV visits in adults. Overall, the weighted frequency (95% confidence interval) of HZV visits increased from 1993-1998 to 2007-2015 (1,269,815 [565,455-1,974,175]-8,017,911 [6,424,491-9,611,331], P = 0.0001). HZV visits were associated with African-American (38.8% [35.8-41.7%] vs. 8.2% [7.4-9.0%]) and Hispanic race/ethnicity (12.6% [6.6-18.5%] vs. 8.0% [7.3-8.5%]), public insurance (42.7% [36.6-49.2%] vs. 33.7% [32.2-35.2%]) in comparison with all other visits. Oral antiviral agents were prescribed in 64.3% (58.1-70.1%) of HZV visits. HZV visits were associated with higher rates of opioid prescriptions compared to all other visits (18.4% [14.0-23.9%] vs. 6.1% [5.6-6.6%], P < 0.0001). The limitation is no data on HZV severity. HZV visits increased over time, even after introduction of HZV vaccines. There were significant racial/ethnic and healthcare disparities of, and high rates of opiate and corticosteroid prescriptions at HZV visits. Future efforts are needed to address these practice gaps, and encourage vaccination and evidence-based prescribing in HZV.

Adult vaccination as the cornerstone of successful ageing: the case of herpes zoster vaccination. A European Interdisciplinary Council on Ageing (EICA) expert focus group

Herpes zoster (HZ) is a painful cutaneous rash with vesicular lesions, lasting up to 3 weeks, and caused by reactivation of the latent varicella zoster virus (VZV). It may be associated with complications, the most feared being post-herpetic neuralgia. Effective vaccines are available to prevent HZ, but uptake remains low. We report here the conclusions of an expert focus group convened by the European Interdisciplinary Council on Ageing (EICA). The group discussed how existing recommendations regarding HZ vaccination could be better implemented, and how compliance and coverage with HZ vaccination could be enhanced. This report proposes strategies to increase awareness of HZ and its vaccine, enhance vaccine uptake, and educate regarding the role of prevention, including immunization, as a means to "age well". A key strategy that could rapidly and easily be implemented at low cost is co-administration of HZ vaccine with other vaccines scheduled in the target age group. The scientific evidence surrounding the safety and efficacy of co-administration is discussed. Other strategies, such as active calls, publicity campaigns and national vaccine registries are also outlined. There is a compelling need for a full consensus document that carries weight across all the healthcare professions involved in vaccination, to issue simple and basic recommendations for all healthcare providers.