Simplified Mathematical Modelling of Uncertainty: Cost-Effectiveness of COVID-19 Vaccines in Spain

Impact of High Covid-19 Vaccination Rate in an Aging Population: Estimating Averted Hospitalizations and Deaths in the Basque Country, Spain Using Counterfactual Modeling

COVID-19 vaccines have demonstrated significant efficacy in reducing severe symptoms and fatalities, although their effectiveness in preventing transmission varies depending on the population's age profile and the dominant variant. This study evaluates the impact of the COVID-19 vaccination campaign in the Basque Country region of Spain, which has the fourth highest proportion of elderly individuals worldwide. Using epidemiological data on hospitalizations, ICU admissions, fatalities, and vaccination coverage, we calibrated four versions of an ordinary differential equations model with varying assumptions on the age structure and transmission function. Counterfactual no-vaccine scenarios were simulated by setting the vaccination rate to zero while all other parameters were held constant. The initial vaccination rollout is estimated to have prevented 46,000 to 75,000 hospitalizations, 6,000 to 11,000 ICU admissions, and 15,000 to 24,000 deaths, reducing these outcomes by 73-86%. The most significant impact occurred during the third quarter of 2021, coinciding with the Delta variant's dominance and a vaccination rate exceeding 60%. Sensitivity analysis revealed that vaccination coverage had a more substantial effect on averted outcomes than vaccine efficacy. Overall, the vaccination campaign in the Basque Country significantly reduced severe COVID-19 outcomes, aligning with global estimates and demonstrating robustness across different modeling approaches.

Economic Evaluation of COVID-19 Immunization Strategies: A Systematic Review and Narrative Synthesis

OBJECTIVES

This study aimed to systematically assess global economic evaluation studies on COVID-19 vaccination, offer valuable insights for future economic evaluations, and assist policymakers in making evidence-based decisions regarding the implementation of COVID-19 vaccination.

METHODS

Searches were performed from January 2020 to September 2023 across seven English databases (PubMed, Web of Science, MEDLINE, EBSCO, KCL-Korean Journal Dataset, SciELO Citation Index, and Derwent Innovations Index) and three Chinese databases (Wanfang Data, China Science and Technology Journal, and CNKI). Rigorous inclusion and exclusion criteria were applied. Data were extracted from eligible studies using a standardized data collection form, with the reporting quality of these studies assessed using the Consolidated Health Economic Evaluation Reporting Standards 2022 (CHEERS 2022).

RESULTS

Of the 40 studies included in the final review, the overall reporting quality was good, evidenced by a mean score of 22.6 (ranging from 10.5 to 28). Given the significant heterogeneity in fundamental aspects among the studies reviewed, a narrative synthesis was conducted. Most of these studies adopted a health system or societal perspective. They predominantly utilized a composite model, merging dynamic and static methods, within short to medium-term time horizons to simulate various vaccination strategies. The research strategies varied among studies, investigating different doses, dosages, brands, mechanisms, efficacies, vaccination coverage rates, deployment speeds, and priority target groups. Three pivotal parameters notably influenced the evaluation results: the vaccine's effectiveness, its cost, and the basic reproductive number (R0). Despite variations in model structures, baseline parameters, and assumptions utilized, all studies identified a general trend that COVID-19 vaccination is cost-effective compared to no vaccination or intervention.

CONCLUSIONS

The current review confirmed that COVID-19 vaccination is a cost-effective alternative in preventing and controlling COVID-19. In addition, it highlights the profound impact of variables such as dose size, target population, vaccine efficacy, speed of vaccination, and diversity of vaccine brands and mechanisms on cost effectiveness, and also proposes practical and effective strategies for improving COVID-19 vaccination campaigns from the perspective of economic evaluation.

Cost-effectiveness of COVID-19 vaccination: A systematic review

OBJECTIVE

The COVID-19 vaccination strategy has been widely used to protect population health worldwide. This study aims to summarize the cost-effectiveness evidence of economic evaluation of COVID-19 vaccination strategies to provide evidence supporting the usage of COVID-19 vaccination, especially where the supply of COVID-19 vaccine is limited.

METHODS

A systematic literature review was performed by searching both English and Chinese databases, including PubMed, Embase, Science Direct, Web of Science, Medline, Scopus, and CNKI. Articles published from January 1, 2020 to August 1, 2022 (PROSPERO registration number: CRD42022355442).

RESULTS

Of the 1035 papers identified, a total of 28 English studies that met the preset criteria were included. COVID-19 vaccination and booster vaccination were cost-effective or cost-saving regardless of the vaccine type; vaccine efficacy, vaccine price, vaccine supply or prioritization, and vaccination pace were the influential factors of cost-effectiveness among different population groups. When supply is adequate, mass vaccination should be encouraged, while when supply is inadequate, prioritizing the high risk and the elderly is more cost-effective.

CONCLUSIONS

COVID-19 vaccination strategies are economically favorable in a wide range of countries and population groups, and further research on suitable strategies for booster COVID-19 vaccination is needed.

Incremental Net Benefit and Incremental Cost-Effectiveness Ratio of COVID-19 Vaccination Campaigns: Systematic Review of Cost-Effectiveness Evidence

SARS-CoV-2 vaccination has been the most effective tool to prevent COVID-19, significantly reducing deaths and hospitalizations worldwide. Vaccination has played a huge role in bringing the COVID-19 pandemic under control, even as the inequitable distribution of vaccines still leaves several countries vulnerable. Therefore, organizing a mass vaccination campaign on a global scale is a priority to contain the virus spread. The aim of this systematic review was to assess whether COVID-19 vaccination campaigns are cost-effective with respect to no vaccination. A systematic literature search was conducted in the WHO COVID-19 Global literature database, PubMed, Web of Science, Embase, and Scopus from 2020 to 2022. Studies assessing the COVID-19 vaccination campaign cost-effectiveness over no vaccination were deemed eligible. The "Drummond's checklist" was adopted for quality assessment. A synthesis of the studies was performed through the "dominance ranking matrix tool". Overall, 10 studies were considered. COVID-19 vaccination was deemed cost-effective in each of them, and vaccination campaigns were found to be sustainable public health approaches to fight the health emergency. Providing economic evaluation data for mass vaccination is needed to support decision makers to make value-based and evidence-based decisions to ensure equitable access to vaccination and reduce the COVID-19 burden worldwide.

Economic evaluation of COVID-19 vaccination: A systematic review

Background

Safe and effective vaccination is considered to be the most critical strategy to fight coronavirus disease 2019 (COVID-19), leading to individual and herd immunity protection. We aimed to systematically review the economic evaluation of COVID-19 vaccination globally.

Methods

We performed a systematic search to identify relevant studies in two major databases (MEDLINE/PubMed and EBSCO) published until September 8, 2022. After deduplication, two researchers independently screened the study titles and abstracts according to pre-determined inclusion and exclusion criteria. The remaining full-text studies were assessed for eligibility. We assessed their quality of reporting using the Consolidated Health Economic Evaluation Reporting Standards (CHEERS) 2022 checklist and summarized and narratively presented the results.

Results

We identified 25 studies that assessed the economic evaluation of COVID-19 vaccination worldwide by considering several input parameters, including vaccine cost, vaccine efficacy, utility value, and the size of the targeted population. All studies suggested that COVID-19 vaccination was a cost-effective or cost-saving intervention for mitigating coronavirus transmission and its effect in many countries within certain conditions. Most studies reported vaccine efficacy values ranging from 65% to 75%.

Conclusions

Given the favorable cost-effectiveness profile of COVID-19 vaccines and disparities in affordability across countries, considering prioritization has become paramount. This review provides comprehensive insights into the economic evaluation of COVID-19 vaccination that will be useful to policymakers, particularly in highlighting preventive measures and preparedness plans for the next possible pandemic.

Cost-Effectiveness of COVID-19 Sequential Vaccination Strategies in Inactivated Vaccinated Individuals in China

To effectively prevent and control the COVID-19 pandemic, countries have adopted a booster vaccination strategy. This study aimed to estimate the cost-effectiveness of sequential booster COVID-19 vaccination compared to two-dose inactivated vaccination in China from a societal perspective. A Markov model was developed to estimate the cost-effectiveness of sequential vaccination, including two doses of an inactivated vaccine followed by a booster shot of an inactivated vaccine, adenovirus vectored vaccine, protein subunit vaccine, or mRNA vaccine. The incremental effects of a booster shot with an inactivated vaccine, protein subunit vaccine, adenovirus vectored vaccine, and mRNA vaccine were 0.0075, 0.0110, 0.0208, and 0.0249 QALYs and saved costs of US$163.96, US$261.73, US$583.21, and US$724.49, respectively. Under the Omicron virus pandemic, the sequential vaccination among adults and the elderly (aged 60-69, 70-79, over 80) was consistently cost-saving, and a booster shot of the mRNA vaccine was more cost-saving. The results indicate that the sequential vaccination strategy is cost-effective in addressing the COVID-19 pandemic, and improving vaccination coverage among the elderly is of great importance in avoiding severe cases and deaths.

Effectiveness and Cost-Effectiveness of Inactivated Vaccine to Address COVID-19 Pandemic in China: Evidence From Randomized Control Trials and Real-World Studies

Objective

This study aimed to determine the efficacy, effectiveness, and cost-effectiveness of inactivated COVID-19 vaccines (CoronaVac and BBIBP-CorV) in China using existing international clinical trials and real-world evidence.

Methods

Through a search of PubMed, Embase, Web of Science, and CNKI, studies investigating the effectiveness of inactivated COVID-19 vaccines were identified, and a meta-analysis was undertaken to synthesize the vaccine efficacy and effectiveness data. Moreover, a decision-analytic model was developed to estimate the cost-effectiveness of inactivated vaccines for combating the COVID-19 pandemic in the Chinese context from a societal perspective. Results of the meta-analysis, along with cost data from official websites and works of literature were used to populate the model. Sensitivity analysis was performed to test the robustness of the model results.

Results

A total of 24 studies were included in the meta-analysis. In comparison to no immunization, the effectiveness of inactivated vaccine against COVID-19 infection, hospitalization, ICU admission and death were 65.18% (95% CI 62.62, 67.75), 79.10% (95% CI 71.69, 86.51), 90.46% (95% CI 89.42, 91.50), and 86.69% (95% CI 85.68, 87.70); and the efficacy against COVID-19 infection and hospitalization were 70.56% (95% CI 57.87, 83.24) and 100% (95% CI 61.72, 100). Inactivated vaccine vaccination prevented more infections, hospitalizations, ICU admissions, and deaths with lower total costs, thus was cost-saving from a societal perspective in China. Base-case analysis results were robust in the one-way sensitivity analysis, and the percentage of ICU admission or death and direct medical cost ranked the top influential factors in our models. In the probabilistic sensitivity analysis, vaccination had a 100% probability of being cost-effective.

Conclusion

Inactivated vaccine is effective in preventing COVID-19 infection, hospitalization, ICU admission and avoiding COVID-19 related death, and COVID-19 vaccination program is cost-saving from societal perspective in China.

Cost-effectiveness of interventions for the prevention and control of COVID-19: Systematic review of 85 modelling studies

Background

We aimed to quantitatively summarise the health economic evaluation evidence of prevention and control programs addressing COVID-19 globally.

Methods

We did a systematic review and meta-analysis to assess the economic and health benefit of interventions for COVID-19. We searched PubMed, Embase, Web of Science, and Cochrane Library of economic evaluation from December 31, 2019, to March 22, 2022, to identify relevant literature. Meta-analyses were done using random-effects models to estimate pooled incremental net benefit (INB). Heterogeneity was assessed using I2 statistics and publication bias was assessed by Egger's test. This study is registered with PROSPERO, CRD42021267475.

Results

Of 16 860 studies identified, 85 articles were included in the systematic review, and 25 articles (10 studies about non-pharmacological interventions (NPIs), five studies about vaccinations and 10 studies about treatments) were included in the meta-analysis. The pooled INB of NPIs, vaccinations, and treatments were $1378.10 (95% CI = $1079.62, $1676.59), $254.80 (95% CI = $169.84, $339.77) and $4115.11 (95% CI = $1631.09, $6599.14), respectively. Sensitivity analyses showed similar findings.

Conclusions

NPIs, vaccinations, and treatments are all cost-effective in combating the COVID-19 pandemic. However, evidence was mostly from high-income and middle-income countries. Further studies from lower-income countries are needed.

Value-based pricing of a COVID-19 vaccine

AIM

The purpose of this study is to determine the value-based price of a COVID-19 vaccine from a societal perspective in Germany.

METHODS

A decision model was constructed using, e.g., information on age-specific fatality rates, intensive care unit (ICU) costs and outcomes, and the full vaccination rate. Three strategies were analysed: vaccination (with 95 % and 50 % efficacy against death), a mitigation strategy, and no intervention. The base-case time horizon was 5 years. The value of a vaccine includes savings from avoiding COVID-19 mitigation measures and productivity loss, as well as health benefits from preventing COVID-19 related mortality. The value of an additional life year was borrowed from new, innovative oncological drugs, as cancer reflects a condition with a similar morbidity and mortality burden in the general population in the short term as COVID-19.

RESULTS

A vaccine with a 95 % efficacy dominates the mitigation strategy strictly. The value-based price (€6,431) is thus determined by the comparison between vaccination and no intervention. The price is particularly sensitive to the full vaccination rate and the duration of vaccine protection. In contrast, the value of a vaccine with 50 % efficacy is more ambiguous.

CONCLUSION

This study yields a value-based price for a COVID-19 vaccine with 95 % efficacy, which is considerably greater than the purchasing price.

Economic Value of Vaccines to Address the COVID-19 Pandemic in Hong Kong: A Cost-Effectiveness Analysis

Objective The coronavirus disease 2019 (COVID-19) pandemic has imposed significant costs on economies. Safe and effective vaccines are a key tool to control the pandemic; however, vaccination programs can be costly. Are the benefits they bestow worth the costs they incur? The relative value of COVID-19 vaccines has not been widely assessed. In this study, a cost-effectiveness analysis was performed to provide evidence of the economic value of vaccines in Hong Kong. Method We developed a Markov model of COVID-19 infections using a susceptible–infected–recovered structure over a 1-year time horizon from a Hong Kong healthcare sector perspective to measure resource utilization, economic burden, and disease outcomes. The model consisted of two arms: do nothing and implement a vaccination program. We assessed effectiveness using units of quality-adjusted life years (QALYs) to measure the incremental cost-effectiveness at a HKD 1,000,000/QALY threshold. Results The vaccination program, which has reached approximately 72% of the population of Hong Kong with two vaccine doses, was found to have a cost of HKD 22,339,700 per QALY gained from February 2021 to February 2022. At a willingness-to-pay threshold, the vaccination program was not cost-effective in the context of the low prevalence of COVID-19 cases before the Omicron wave. However, the cost-effectiveness of a COVID-19 vaccine is sensitive to the infection rate. Hong Kong is now experiencing the fifth wave of the Omicron. It is estimated that the ICER of the vaccination program from February 2022 to February 2023 was HKD 310,094. The vaccination program in Hong Kong was cost-effective in the context of the Omicron. Conclusions Vaccination programs incur a large economic burden, and we therefore need to acknowledge their limitations in the short term. This will help relevant departments implement vaccination programs. From a longer-term perspective, the vaccination program will show great cost-effectiveness once infection rates are high in a regional outbreak. Compared with other age groups, it is suggested that the elderly population should be prioritized to improve the vaccine coverage rate.