Prioritization of the Target Population for Coronavirus Disease 2019 (COVID-19) Vaccination Program in Thailand

COVID-19 vaccination status in people with spinal cord injury: Results from a cross-sectional study in Thailand

OBJECTIVE

To assess COVID-19 vaccination status among individuals with spinal cord injury (SCI).

DESIGN

A cross-sectional study.

SETTING

Twelve hospitals from all regions of Thailand.

PARTICIPANTS

One hundred and eighty people with SCI were randomly selected from the Thai SCI registry database.

INTERVENTION

Not applicable.

OUTCOME MEASURES

The primary outcome, which was the COVID-19 vaccination status, and the secondary outcomes, which were the number of vaccination doses, satisfaction and dissatisfaction aspects, and barriers to vaccination, were recorded using a specifically developed questionnaire over the telephone during February to March 2022. Data were analyzed using descriptive analyses, bivariate, and multivariable analyses.

RESULTS

Of the 96 people with SCI who were able to respond, the prevalence of receiving at least one dose was 77% but the prevalence of receiving a booster dose was 20%. Being non-traumatic SCI correlated negatively with having received any vaccination doses when compared to traumatic SCI. Most of the participants were satisfied with the government provision of COVID-19 vaccines. The major barriers to vaccination were problems related to a negative attitude toward the vaccination, followed by transportation difficulties and wheelchair-inaccessible vaccination sites.

CONCLUSIONS

Seventy-seven percent of people with SCI participating in this study received at least one dose of the COVID-19 vaccine, whereas only 20% of them received a booster dose of the COVID-19 vaccination. To increase the prevalence of vaccination, healthcare providers should deliver the fact regarding COVID-19 vaccination to reduce negative attitudes, as well as remove physical barriers to vaccination places for people with SCI.

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.

Predictive models for health outcomes due to SARS-CoV-2, including the effect of vaccination: a systematic review

BACKGROUND

The interaction between modelers and policymakers is becoming more common due to the increase in computing speed seen in recent decades. The recent pandemic caused by the SARS-CoV-2 virus was no exception. Thus, this study aims to identify and assess epidemiological mathematical models of SARS-CoV-2 applied to real-world data, including immunization for coronavirus 2019 (COVID-19).

METHODOLOGY

PubMed, JSTOR, medRxiv, LILACS, EconLit, and other databases were searched for studies employing epidemiological mathematical models of SARS-CoV-2 applied to real-world data. We summarized the information qualitatively, and each article included was assessed for bias risk using the Joanna Briggs Institute (JBI) and PROBAST checklist tool. The PROSPERO registration number is CRD42022344542.

FINDINGS

In total, 5646 articles were retrieved, of which 411 were included. Most of the information was published in 2021. The countries with the highest number of studies were the United States, Canada, China, and the United Kingdom; no studies were found in low-income countries. The SEIR model (susceptible, exposed, infectious, and recovered) was the most frequently used approach, followed by agent-based modeling. Moreover, the most commonly used software were R, Matlab, and Python, with the most recurring health outcomes being death and recovery. According to the JBI assessment, 61.4% of articles were considered to have a low risk of bias.

INTERPRETATION

The utilization of mathematical models increased following the onset of the SARS-CoV-2 pandemic. Stakeholders have begun to incorporate these analytical tools more extensively into public policy, enabling the construction of various scenarios for public health. This contribution adds value to informed decision-making. Therefore, understanding their advancements, strengths, and limitations is essential.

A Scoping Review and Taxonomy of Epidemiological-Macroeconomic Models of COVID-19

OBJECTIVES

The COVID-19 pandemic placed significant strain on many health systems and economies. Mitigation policies decreased health impacts but had major macroeconomic impact. This article reviews models combining epidemiological and macroeconomic projections to enable policy makers to consider both macroeconomic and health objectives.

METHODS

A scoping review of epidemiological-macroeconomic models of COVID-19 was conducted, covering preprints, working articles, and journal publications. We assessed model methodologies, scope, and application to empirical data.

RESULTS

We found 80 articles modeling both the epidemiological and macroeconomic outcomes of COVID-19. Model scope is often limited to the impact of lockdown on health and total gross domestic product or aggregate consumption and to high-income countries. Just 14% of models assess disparities or poverty. Most models fall under 4 categories: compartmental-utility-maximization models, epidemiological models with stylized macroeconomic projections, epidemiological models linked to computable general equilibrium or input-output models, and epidemiological-economic agent-based models. We propose a taxonomy comparing these approaches to guide future model development.

CONCLUSIONS

The epidemiological-macroeconomic models of COVID-19 identified have varying complexity and meet different modeling needs. Priorities for future modeling include increasing developing country applications, assessing disparities and poverty, and estimating of long-run impacts. This may require better integration between epidemiologists and economists.

Impact of vaccination and non-pharmacological interventions on COVID-19: a review of simulation modeling studies in Asia

Introduction

Epidemiological modeling is widely used to offer insights into the COVID-19 pandemic situation in Asia. We reviewed published computational (mathematical/simulation) models conducted in Asia that assessed impacts of pharmacological and non-pharmacological interventions against COVID-19 and their implications for vaccination strategy.

Methods

A search of the PubMed database for peer-reviewed, published, and accessible articles in English was performed up to November 2022 to capture studies in Asian populations based on computational modeling of outcomes in the COVID-19 pandemic. Extracted data included model type (mechanistic compartmental/agent-based, statistical, both), intervention type (pharmacological, non-pharmacological), and procedures for parameterizing age. Findings are summarized with descriptive statistics and discussed in terms of the evolving COVID-19 situation.

Results

The literature search identified 378 results, of which 59 met criteria for data extraction. China, Japan, and South Korea accounted for approximately half of studies, with fewer from South and South-East Asia. Mechanistic models were most common, either compartmental (61.0%), agent-based (1.7%), or combination (18.6%) models. Statistical modeling was applied less frequently (11.9%). Pharmacological interventions were examined in 59.3% of studies, and most considered vaccination, except one study of an antiviral treatment. Non-pharmacological interventions were also considered in 84.7% of studies. Infection, hospitalization, and mortality were outcomes in 91.5%, 30.5%, and 30.5% of studies, respectively. Approximately a third of studies accounted for age, including 10 that also examined mortality. Four of these studies emphasized benefits in terms of mortality from prioritizing older adults for vaccination under conditions of a limited supply; however, one study noted potential benefits to infection rates from early vaccination of younger adults. Few studies (5.1%) considered the impact of vaccination among children.

Conclusion

Early in the COVID-19 pandemic, non-pharmacological interventions helped to mitigate the health burden of COVID-19; however, modeling indicates that high population coverage of effective vaccines will complement and reduce reliance on such interventions. Thus, increasing and maintaining immunity levels in populations through regular booster shots, particularly among at-risk and vulnerable groups, including older adults, might help to protect public health. Future modeling efforts should consider new vaccines and alternative therapies alongside an evolving virus in populations with varied vaccination histories.

Impact of COVID-19 Vaccination Rates and Public Measures on Case Rates at the Provincial Level, Thailand, 2021: Spatial Panel Model Analyses

The coronavirus disease of 2019 (COVID-19) was a pandemic that caused high morbidity and mortality worldwide. The COVID-19 vaccine was expected to be a game-changer for the pandemic. This study aimed to describe the characteristics of COVID-19 cases and vaccination in Thailand during 2021. An association between vaccination and case rates was estimated with potential confounders at ecological levels (color zones, curfews set by provincial authorities, tourism, and migrant movements) considering time lags at two, four, six, and eight weeks after vaccination. A spatial panel model for bivariate data was used to explore the relationship between case rates and each variable and included only a two-week lag after vaccination for each variable in the multivariate analyses. In 2021, Thailand had 1,965,023 cumulative cases and 45,788,315 total administered first vaccination doses (63.60%). High cases and vaccination rates were found among 31-45-year-olds. Vaccination rates had a slightly positive association with case rates due to the allocation of hot-spot pandemic areas in the early period. The proportion of migrants and color zones measured had positive associations with case rates at the provincial level. The proportion of tourists had a negative association. Vaccinations should be provided to migrants, and collaboration between tourism and public health should prepare for the new era of tourism.

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.

The Effects of CoronaVac and ChAdOx1 nCoV-19 in Reducing Severe Illness in Thailand: A Retrospective Cohort Study

Two primary vaccines for coronavirus disease 2019 (COVID-19) have been rolled out in the mass vaccination campaign that started simultaneously with the spread of the delta variant. To explore the vaccines' effect on reducing viral load and disease severity, we conducted a retrospective cohort study in Thai patients aged ≥18 years who were confirmed COVID-19 positive by RT-PCR. Compared to unvaccinated patients, Ct values and the number of severe cases among vaccine regimens were analyzed. Ct values of vaccinated patients were not significantly different from unvaccinated patients, despite an increase of Ct values in a booster dose. The adjusted odd ratio for prevention of delta-related severe diseases was 0.47, 95% CI: 0.30-0.76 and 0.06, 95% CI: 0.01-0.45 after receiving one dose and two doses, respectively. No severe illness was found in booster-vaccinated individuals. Focusing on the vaccine types, one dose of ChAdOx1 nCoV-19 gave significant protection, whereas one dose of CoronaVac did not (0.49, 95% CI: 0.30-0.79, p = 0.003 vs. 0.28, 95% CI: 0.04-2.16, p = 0.223). Two-dose vaccination showed robust protective effects in all subpopulations regardless of vaccine type. Vaccinations with two primary vaccines could not reduce viral load in patients with COVID-19, but could prevent severe illness.

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 Analysis of COVID-19 Vaccination in Low- and Middle-Income Countries

Background

WHO reported that 5.5 million people died in the world because of COVID-19. One of the efforts to mitigate the pandemic is administrating the vaccines globally.

Objective

The objective of this study was to review cost-effectiveness analysis of COVID-19 vaccination in low- and middle-income countries (LMICs).

Methods

We searched PubMed and EBSCO for the eligible studies with inclusion criteria using cost-effectiveness analysis, free full text, low-middle-income countries, and the publication date since the last year. Four reviewers conducted the review independently.

Results

The review identified four articles meeting the eligibility criteria. The settings were LMICs. Different perspectives and economic modelling used by the countries confirmed a similar result. They all explained that vaccination could prevent the infection spread and mortality caused by COVID-19 and showed high cost-effectiveness values.

Conclusion

Administering COVID-19 vaccines was cost-effective and even cost-saving. The studies found that vaccination was more cost-effective in reducing the spread of the COVID-19 virus and the mortality it caused than no vaccination.

Using simulation modelling and systems science to help contain COVID-19: A systematic review

This study systematically reviews applications of three simulation approaches, that is, system dynamics model (SDM), agent-based model (ABM) and discrete event simulation (DES), and their hybrids in COVID-19 research and identifies theoretical and application innovations in public health. Among the 372 eligible papers, 72 focused on COVID-19 transmission dynamics, 204 evaluated both pharmaceutical and non-pharmaceutical interventions, 29 focused on the prediction of the pandemic and 67 investigated the impacts of COVID-19. ABM was used in 275 papers, followed by 54 SDM papers, 32 DES papers and 11 hybrid model papers. Evaluation and design of intervention scenarios are the most widely addressed area accounting for 55% of the four main categories, that is, the transmission of COVID-19, prediction of the pandemic, evaluation and design of intervention scenarios and societal impact assessment. The complexities in impact evaluation and intervention design demand hybrid simulation models that can simultaneously capture micro and macro aspects of the socio-economic systems involved.