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

Lessons for medical countermeasure development from unforeseen outbreaks

The unanticipated emergence of the COVID-19 pandemic and the rapid spread of the mpox epidemic in 2022 and 2024 brought unforeseen challenges to public health. While distinct in nature, these outbreaks share some similarities and offer valuable insights into responding to novel virus dissemination in vulnerable populations. In light of these two experiences, we aim to discern the prioritization of medical countermeasures (MCM) among antivirals, antibodies, and vaccines. Comparative analysis of MCMs reveals that while antivirals serve essential roles as therapeutic tools, monoclonal antibodies can be used for both prevention and treatment, and vaccines remain of paramount importance for controlling epidemics as mass or targeted prophylaxis. Variability in production processes, administration methods, logistics, and costs distinguish these countermeasures. Vaccines, by inducing long-lasting immunity and ideally promoting herd effects, exhibit substantial advantages over other options. To enhance future pandemic readiness, proactive measures must include ready-to-use vaccine platforms with regulatory approval and manufacturing capacities, as well as prototype vaccines for representative pathogens and preexisting protocols to evaluate their efficacies and side effects. The comparison underscores the challenges of social acceptance and equity, particularly in vaccine production and distribution. As the world faces unknown agents, the three major types of MCMs do not have equal and symmetrical effects in terms of epidemic control. Thus, a vaccine-oriented strategy with a community-centered approach, proves essential for effective pandemic preparedness, encouraging continued innovation in vaccinology.

The path to prevention of multiple sclerosis: Considerations for Epstein-Barr virus vaccine-based prevention studies

Recent advancements in our understanding of the association between Epstein-Barr virus (EBV) and multiple sclerosis (MS), along with progress in EBV vaccine development, warrant serious considerations of future EBV vaccine-based MS-prevention studies. The clinical, financial, logistical, and technological considerations for designing and conducting retrospective and/or prospective prevention studies with the primary objective of evaluating the effectiveness of EBV vaccines in preventing MS and other EBV-associated sequelae are presented here. As implementation of these studies may require hundreds of thousands of participants, millions of dollars, and decades to observe if meaningful reductions in MS incidence occur, alternative approaches using pragmatic phase IV, post-licensure study designs focused on either the prevention of MS or infectious mononucleosis (IM), a common clinical manifestation of EBV infection that has been associated with increased risk of MS, are also explored. Current knowledge gaps in technology, funding, and research that must be addressed for a study protocol to be successfully designed and implemented are also discussed.

Value of Vaccinations: A Fundamental Public Health Priority to Be Fully Evaluated

INTRODUCTION

Vaccinations are one of the most impactful public health interventions, saving millions of lives annually and reducing the spread of infectious diseases. Numerous vaccines are expected to become available in the future. Decision-makers will have to thoroughly evaluate them. It is essential to fully comprehend the value of vaccinations to effectively and efficiently guide decisions.

METHODS

This work aims to highlight the multifaceted benefits of vaccination, extending beyond clinical outcomes to encompass profound economic and societal advantages.

RESULTS

Vaccinations should be considered an investment, not a cost. In comparison to other health expenditures, the vaccine costs can be considered moderate. Vaccinations can also reduce the fiscal burden by avoiding diseases, minimizing lost workdays and absenteeism, lowering disability claims, and increasing workforce productivity. The costs of non-vaccination represent a relevant issue. Vaccination also plays a key role in addressing the global challenge of antimicrobial resistance. Apart from quantifiable economic parameters, vaccines also have intangible benefits reducing pain and avoiding quality of life lost and deaths.

CONCLUSIONS

Comprehensive Health Technology Assessments are required to understand the overall value of vaccinations.

Cost-effectiveness models assessing COVID-19 booster vaccines across eight countries: A review of methods and data inputs

Coronavirus disease 2019 (COVID-19) continues to cause serious health consequences globally. Policy makers now assess cost effectiveness (CE) when evaluating COVID-19 vaccines. A targeted literature review was performed to examine recent CE evidence for COVID-19 vaccines, as severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) transitions from pandemic to endemic, to identify best practices. Data were from large EU countries (UK, Spain, Germany, France, and Italy), US, Canada, and Australia. Nine CE studies met the inclusion criteria. Studies evaluated booster vaccination, and mainly considered mRNA vaccines. CE studies reported that COVID-19 vaccines provided health benefits and were cost-effective or showed cost-savings. Benefits were more pronounced in older and high-risk populations based on higher rates of COVID-19 hospitalization and death. CE findings were most sensitive to estimates of incidence of COVID-19, SARS-CoV-2 transmissibility, vaccine effectiveness, waning/duration of vaccine protection, and hospitalization costs. Most data inputs were sourced from real-world evidence (RWE). Lack of inclusion of some parameters, such as transmission modeling, productivity losses, and the impact of long COVID may undervalue COVID-19 vaccines. As SARS-CoV-2 evolves and COVID-19 vaccines are updated, continuous generation of RWE is needed to demonstrate the CE of COVID-19 vaccines in an ongoing manner.

Health Preferences in Transition: Differences from Pandemic to Post-Pandemic in Valuation of COVID-19 and RSV Illness in Children and Adults

Objective: This study aimed to measure changes in preferences regarding health-related quality of life associated with COVID-19 and RSV illness in children and adults from 2021 (during the COVID-19 pandemic) to 2023 (post-pandemic). Methods: A stated-preference survey elicited time trade-off (TTO) values from US adults in spring 2021 (n = 1014) and summer 2023 (n = 1186). Respondents were asked to indicate how much time they would hypothetically be willing to trade from the end of their life to avoid the effects of varying severities of COVID-19 and RSV illness for: (1) children; (2) parents of an ill child (family spillover); and (3) adults. Attitudes relating to COVID-19 vaccination and data on experience with COVID-19 or RSV illness were also collected. The primary outcome measure was the loss in quality-adjusted life years (QALYs). Changes in preferences over the time period from 2021 to 2023 were evaluated using regression analysis. Results: QALY losses increased with disease severity and were highest for Long COVID. Across all COVID-19 and RSV health states, QALY losses associated with child health states were higher than family spillover or adult health states. In the regression analysis, QALY losses reported in the 2023 survey were significantly lower than 2021 QALY losses for COVID-19, but not RSV. Conclusions: Preferences may change over time in a pandemic context and therefore, economic analyses of pandemic interventions should consider the timeframe of health preference data collection to determine whether they are suitable to include in an economic evaluation. Even with the impacts on health-related quality of life attenuated over time, childhood illnesses still had a measurable impact on caregivers' quality of life.

Comparison of Phenotypes of Headaches After COVID-19 Vaccinations Differentiated According to the Vaccine Used

Background/Objectives: In this ongoing, multicenter, global cohort observational study, phenotypes of headaches after COVID-19 vaccination were directly compared between different vaccines. Methods: Phenotypes of postvaccinal headache were recorded in 18,544 participants. The study was launched immediately after the start of the global COVID-19 vaccination campaign on 12 January 2021 and continued until 1 August 2023. Specific aspects of headaches and related variables were collected via an online questionnaire. The clinical headache characteristics of patients vaccinated with the Comirnaty (BioNTech), Jcovden (Johnson & Johnson), Sputnik V (Gamelaya), Covilo (Sinopharm), Spikevax (Moderna), Vaxzevria (AstraZeneca), and Convidecia (CanSino Biologics) vaccines were investigated. Results: Across all vaccines, the median and mean latency of headache onset after vaccine administration were 12 h and 23.3 h, respectively. The median and mean headache duration were 12 h and 23.3 h, respectively. When the nonreplicating viral vector vaccine Sputnik V was used, headaches occurred the fastest, with a latency of 17 h. The latencies for the Vaxzevria and Convidecia nonreplicating viral vector vaccines were 14.9 h and 19.1 h, respectively. The Covilo inactivated whole-virus vaccine had a latency of 20.5 h. The latencies of the mRNA-based Comirnaty and Spikevax vaccines were 26.0 h and 22.02 h, respectively. Analysis of variance revealed no significant differences in the mean duration of postvaccinal headache for the vaccines tested. Compared with the Comirnaty, Covilo, and Vaxzevria vaccines, the Spikevax vaccine induced significantly greater headache intensities. Vaxzevria was associated with a significantly higher frequency of concomitant symptoms than the other vaccines. Conclusions: The phenotype of postvaccinal headache can vary significantly between vaccines. These results have clinical implications for differentiating between postvaccinal headache and other primary and secondary headaches. This knowledge is clinically relevant in differentiating life-threatening vaccination complications, such as thrombotic syndromes, which are also associated with headaches. Based on these results, new diagnostic criteria for postvaccinal headaches can be developed.

The Impact of Vaccination on COVID-19, Influenza, and Respiratory Syncytial Virus-Related Outcomes: A Narrative Review

Vaccination represents a core preventive strategy for public health, with interrelated and multifaceted effects across health and socioeconomic domains. Beyond immediate disease prevention, immunization positively influences downstream health outcomes by mitigating complications of preexisting comorbidities and promoting healthy aging. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), influenza virus, and respiratory syncytial virus (RSV) are common respiratory viruses responsible for broad societal cost and substantial morbidity and mortality, particularly among at-risk individuals, including older adults and people with frailty or certain comorbid conditions. In this narrative review, we summarize the overall impact of vaccination for these 3 viruses, focusing on mRNA vaccines, each of which exhibits unique patterns of infection, risk, and transmission dynamics, but collectively represent a target for preventive strategies. Vaccines for COVID-19 (caused by SARS-CoV-2) and influenza are effective against the most severe outcomes, such as hospitalization and death; these vaccines represent the most potent and cost-effective interventions for the protection of population and individual health against COVID-19 and influenza, particularly for older adults and those with comorbid conditions. Based on promising results of efficacy for the prevention of RSV-associated lower respiratory tract disease, the first RSV vaccines were approved in 2023. Immunization strategies should account for various factors leading to poor uptake, including vaccine hesitancy, socioeconomic barriers to access, cultural beliefs, and lack of knowledge of vaccines and disease states. Coadministration of vaccines and combination vaccines, such as multicomponent mRNA vaccines, offer potential advantages in logistics and delivery, thus improving uptake and reducing barriers to adoption of new vaccines. The success of the mRNA vaccine platform was powerfully demonstrated during the COVID-19 pandemic; these and other new approaches show promise as a means to overcome existing challenges in vaccine development and to sustain protection against viral changes over time.A graphical abstract and video abstract is available with this article.

The cost-effectiveness of COVID-19 vaccination program among age-groups children, adults, and elderly in Europe: A systematic review

Objectives

To prepare for future epidemics, the experiences from the vaccination programs in the COVID-19 pandemic need to be collated. This systematic review synthesizes health economic evidence of COVID-19 vaccination programs in European countries comparing the target groups children, adults, and elderly, to study whether the Swedish vaccination strategy was justified on cost-effectiveness grounds.

Method

A literature search using the PICOS (Population, Intervention, Control, Outcomes, Study design) convention was conducted in the databases Medline, Embase, PsycInfo, CINAHL, and Tuft CEA Registry, Cochrane and INAHTA in February 2023. The inclusion criteria were economic evaluations (S) comparing COVID-19 vaccination (I) in age-groups children, adult, and elderly European residents (P) with non-vaccinated European residents (C) in terms of cost per QALY, cost differences, and net monetary benefit (O). Hand-search was done on selected websites and in reference lists of included reports. Title/abstract screening, full-text screening, and quality assessment with the Swedish HTA agency checklist were performed by two researchers. The reporting follows the PRISMA 2020 recommendations.

Results

The database search resulted in 5,720 reports, title/abstract screening yielded 162 reports and after full-text screening, four reports remained. Two studies comparing vaccination of adults and elderly with high and moderate study quality were included. No study was found on the children population. The economic evidence indicated that COVID-19 vaccination of the elderly is cost-effective when compared with vaccination of the adult group, but the transferability to Swedish circumstances was inconclusive due to differences in outcome and cost data between Sweden and the included studies' settings.

Conclusion

The common European COVID-19 vaccination policy that prioritized the elderly population was the cost-effective option in the reviewed studies. The lack of transferability to Sweden precludes a clear conclusion on the Swedish vaccination policy.

Cost-effectiveness analysis of COVID-19 booster doses and oral antivirals: Case studies in the Indo-Pacific

BACKGROUND

Decision-makers in middle-income countries need evidence on the cost-effectiveness of COVID-19 booster doses and oral antivirals to appropriately prioritise these healthcare interventions.

METHODS

We used a dynamic transmission model to assess the cost-effectiveness of COVID-19 booster doses and oral antivirals in Fiji, Indonesia, Papua New Guinea, and Timor-Leste. We conducted cost-effectiveness analysis from both healthcare and societal perspectives using data collated from publicly available sources. We developed an interactive R Shiny which allows the user to vary key model assumptions, such as the choice of discounting rate, and view how these assumptions affect model results.

FINDINGS

Booster doses were cost saving and therefore cost-effective in all four middle-income settings from both healthcare and societal perspectives using 3% discounting. Providing oral antivirals was cost-effective from a healthcare perspective if procured at a low generic price (US$25) or middle-income reference price (US$250); however, their cost-effectiveness was strongly influenced by rates of wastage or misuse, and the ongoing costs of care for patients hospitalised with COVID-19. The cost or wastage of rapid antigen tests did not appear strongly influential over the cost-effectiveness of oral antivirals in any of the four study settings.

CONCLUSIONS

Our results support that COVID-19 booster programs are cost-effective in middle-income settings. Oral antivirals demonstrate the potential to be cost-effective if procured at or below a middle-income reference price of US$250 per schedule. Further research should quantify the rates of wastage or misuse of oral COVID-19 antivirals in middle-income settings.

Cost effectiveness analysis comparing varying booster intervals of vaccination policies to address COVID-19 situation in Thailand, 2023

The COVID-19 booster immunization policy is cost-effective, but evidence on additional booster doses and appropriate strategies is scarce. This research compared the cost-effectiveness of annual, twice-a-year, and biennial booster dose policies. We performed stochastic modeling using compartmental susceptible-exposed-infectious-recovered models and a system dynamic model. We evaluated four policy scenarios: (1) hypothetical no-booster immunization policy; (2) twice-a-year vaccination policy; (3) annual vaccination policy; and (4) biennial vaccination policy. In addition, we conducted a one-way sensitivity analysis by adjusting R0 from 1.8 to 3.0 in all scenarios (epidemic stage) and by decreasing the vaccination cost by 50% at the end of the first year to reflect the current policy direction to enhance domestic vaccine production. Compared to non-booster policies, all three booster strategies reduced the number of cases, hospital admissions, and severe infections remarkably. Without a booster, total cases would reach 16,220,615 (95% confidence interval [CI] 6,726,550-29,661,112) by day 1,460, whereas, with a twice-a-year booster, the total cases would reach 597,901 (95% CI 526,230-694,458) in the same period. Even though the no booster scenario exhibited the lowest cost by approximately the first 500 days, by day 1,460 the biennial booster scenario demonstrated the lowest cost at 72.0 billion baht (95% CI 68.6-79.4 billion). The most cost-saving policy was the biennial booster scenario. The annual booster scenario also stood as a cost-effective option for most outcomes. In the epidemic stage and in an assumption where the vaccination costs dropped, all booster policies became more cost-effective or cost-saving compared with the main assumption. This study underscores the significance of the COVID-19 vaccine booster policy. Implementing policies should take into consideration cost-effectiveness, feasibility, and public communication.

New Vaccines for Chronic Respiratory Patients

Chronic respiratory diseases (CRD) are responsible for more than four million deaths worldwide and have become especially prevalent in developed countries. Although the current therapies help manage daily symptoms and improve patients' quality of life, there is a major need to prevent exacerbations triggered mainly by respiratory infections. Therefore, CRD patients are a prime target for vaccination against infectious agents. In the present manuscript we review the state of the art of available vaccines specifically indicated in patients with CRDs. In addition to pneumococcus, influenza, pertussis, and SARS-CoV-2 vaccines, recently added immunization options like vaccines and monoclonal antibodies against respiratory syncytial virus, are particularly interesting in CRD patients. As new products reach the market, health authorities must be agile in updating immunization recommendations and in the programming of the vaccination of vulnerable populations such as patients with CRDs. Organizational and educational strategies might prove useful to increase vaccine uptake by CRD patients.

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.

Avoidable COVID-19-related deaths and hospitalizations in Brazil, 2020-2023

OBJECTIVE

To estimate the number of avoidable COVID-19 deaths and hospitalizations in Brazil.

METHODS

Secondary data on COVID-19 deaths and hospitalizations were related to two measures of cumulative vaccine coverage (in the last six months and before this period) by negative binomial regression to estimate population-level protective effectiveness (PLPE) against severe disease. The latter includes the overall protective effect of all COVID-19-preventive measures, such as direct and indirect vaccine effectiveness, social distancing, and lockdown, but only the vaccine coverage data were available for the regression analysis.

RESULTS

COVID-19 mortality rates per 100,000 inhabitants were 10.26, 16.45, 0.14, and 0.94, for the years 2020, 2021, 2022, and the first half of 2023. In the same order and scale, COVID-19 hospitalization rates were 28.96, 47.04, 0.40, and 3.74. Both hospitalizations and deaths peaked early in 2021, then sharply reduced by the end of the year as the first-dose vaccine coverage reached 90 %, and rose with the vaccine coverage within the last six months falling below 10 % in 2023. PLPE for preventing COVID-19 deaths was 19.9 %, 98.9 %, and 93.1 % for the years 2021, 2022, and the first half of 2023. Had Brazil vaccinated the same number of people against COVID-19 in the last quarter of 2020 as it did in the first quarter of 2021, over 117,000 deaths and 277,000 hospitalizations could have been avoided over the period analyzed.

CONCLUSIONS

PLPE reduction in 2023 was likely caused by low vaccine uptake. The disease burden could have been much lower had the vaccination started earlier and had the vaccine uptake not dropped so sharply in 2023.

Clinical impact and cost-effectiveness of the updated COVID-19 mRNA Autumn 2023 vaccines in Germany

OBJECTIVES

To assess the potential clinical impact and cost-effectiveness of coronavirus disease 2019 (COVID-19) mRNA vaccines updated for Autumn 2023 in adults aged ≥60 years and high-risk persons aged 30-59 years in Germany over a 1-year analytic time horizon (September 2023-August 2024).

METHODS

A compartmental Susceptible-Exposed-Infected-Recovered model was updated and adapted to the German market. Numbers of symptomatic infections, a number of COVID-19 related hospitalizations and deaths, costs, and quality-adjusted life-years (QALYs) gained were calculated using a decision tree model. The incremental cost-effectiveness ratio of an Autumn 2023 Moderna updated COVID-19 (mRNA-1273.815) vaccine was compared to no additional vaccination. Potential differences between the mRNA-1273.815 and the Autumn Pfizer-BioNTech updated COVID-19 (XBB.1.5 BNT162b2) vaccines, as well as societal return on investment for the mRNA-1273.815 vaccine relative to no vaccination, were also examined.

RESULTS

Compared to no autumn vaccination, the mRNA-1273.815 campaign is predicted to prevent approximately 1,697,900 symptomatic infections, 85,400 hospitalizations, and 4,100 deaths. Compared to an XBB.1.5 BNT162b2 campaign, the mRNA-1273.815 campaign is also predicted to prevent approximately 90,100 symptomatic infections, 3,500 hospitalizations, and 160 deaths. Across both analyses we found the mRNA-1273.815 campaign to be dominant.

CONCLUSIONS

The mRNA-1273.815 vaccine can be considered cost-effective relative to the XBB.1.5 BNT162b2 vaccine and highly likely to provide more benefits and save costs compared to no vaccine in Germany, and to offer high societal return on investment.

Comparison of healthcare resource use and cost between influenza and COVID-19 vaccine coadministration and influenza vaccination only

OBJECTIVE

To compare healthcare resource utilization (HCRU) and all-cause medical costs among individuals aged ≥50 years who received influenza and COVID-19 vaccines on the same day and those who received influenza vaccine only.

METHODS

We conducted a retrospective cohort study leveraging Optum's de-identified Clinformatics DataMart from 8/31/2021 to 7/31/2023. Individuals aged ≥50 years continuously enrolled in health plans for 1 year prior and until 7/31/2023 were included. Two cohorts were formed based on vaccination status between 8/31/2022 and 1/31/2023: co-administered influenza and COVID-19 vaccines (co-admin cohort) and influenza vaccine only (influenza cohort). Associations between vaccination status and all-cause, influenza-related, COVID-related, pneumonia-related, and cardiorespiratory-related hospitalization, outpatient or emergency room visits and all-cause medical costs were estimated by weighted generalized linear models, adjusting for confounding by stabilized inverse probability of treatment weighting.

RESULTS

613,156 (mean age: 71) and 1,340,011 (mean age: 72) individuals were included in the co-admin and influenza cohorts, respectively. After weighting, the baseline characteristics were balanced between cohorts. The co-admin cohort was at statistically significant lower risk of all-cause (RR: 0.95, 95% CI: 0.93-0.96), COVID-19-related (RR: 0.59, 95% CI: 0.56-0.63), cardiorespiratory-related (RR: 0.94, 95% CI: 0.93-0.96) and pneumonia-related (RR: 0.86, 95% CI: 0.83-0.90) hospitalization but not influenza-related hospitalizations (RR: 0.91, 95% CI: 0.81, 1.04) compared with the influenza cohort. Co-administration was associated with 3% lower all-cause medical cost (cost ratio: 0.974, 95% CI: 0.968, 0.979) during the follow-up period compared to receiving influenza vaccine only.

LIMITATIONS

Limitations include the potential residual confounding bias in observational data, measurement errors from claims data, and that the cohort was followed for a single season.

CONCLUSION

Receiving co-administered COVID-19 and influenza vaccines versus only receiving influenza vaccination reduced the risk of HCRU, especially COVID-19-related hospitalization and all-cause medical costs. Increasing vaccine coverage, particularly for COVID-19, might have public health and economic benefits.