Cost-benefit analysis of human adenovirus vaccine development in a Korean military setting.

BACKGROUND: Human adenovirus (HAdV) is a prevalent causative agent of acute respiratory disease (ARD) and is frequently responsible for outbreaks, particularly in military environments. Current vaccines do not effectively cover HAdV subtypes commonly found among Korean military personnel, highlighting the need for a new targeted vaccine. This study presents a cost-benefit analysis to evaluate the economic viability of developing and implementing such a vaccine within a military context. METHODS: We adopted a societal perspective for this cost-benefit analysis, which included estimating costs associated with vaccine development, production, and distribution over a projected timeline. We assumed a development period of five years, after which vaccine production and administration were initiated in the sixth year. The cost associated with vaccine development, production, and dispensation was considered. The benefits were calculated based on both direct and indirect cost savings from preventing HAdV infections through vaccination. All financial figures were expressed in 2023 US dollars. A sensitivity analysis was conducted to explore the impact of varying factors such as vaccination rate, incidence of infection, vaccine efficacy, and discount rate. RESULTS: For the base case scenario, we assumed a vaccination rate of 100 %, an incidence rate of 0.02, and a vaccine efficacy of 95 %, applying a 3 % discount rate. Initially, in the sixth year, the benefit-cost ratio stood at 0.71, suggesting a cost disadvantage at the onset of vaccination. However, this ratio improved to 1.32 in the following years, indicating a cost benefit from the seventh year onward. The cumulative benefit-cost ratio over a decade reached 2.72. The outcomes from the sensitivity analysis were consistent with these findings. CONCLUSION: Our cost-benefit analysis demonstrates that the introduction of an HAdV vaccine for the Korean military is economically advantageous, with substantial cost benefits accruing from the seventh year after the commencement of vaccination.

Inference and forecasting phase shift regime of COVID-19 sub-lineages with a Markov-switching model.

IMPORTANCE: Using regime-switching models, we attempted to determine whether there is a link between changes in severe acute respiratory syndrome coronavirus 2 (SARS-Cov-2) variants and infection waves, as well as forecasting new SARS-Cov-2 variants. We believe that our study makes a significant contribution to the field because it proposes a new approach for forecasting the ongoing pandemic, and the spread of other infectious diseases, using a statistical model which incorporates unpredictable factors such as human behavior, political factors, and cultural beliefs.

A Model-Based Cost-Effectiveness Analysis of Long-Acting Monoclonal Antibody (Tixagevimab and Cilgavimab: Evusheld) Preventive Treatment for High-Risk Populations Against SARS-CoV-2 in Korea.

BACKGROUND: Tixagevimab and cilgavimab (Evusheld) administration is a recommended strategy for unvaccinated patients with immunocompromised conditions and severe allergic reaction conditions to protect high-risk individuals and control the coronavirus disease 2019 (COVID-19) epidemic. We estimated the cost-effectiveness of Evusheld in key risk populations: 1) immunocompromised (vaccinated/unvaccinated), 2) severe allergic reaction, and 3) unvaccinated elderly high-risk groups. METHODS: Based on the estimated target risk group population, we used a model of COVID-19 transmission to estimate the size of the risk group population for whom Evusheld treatment may help prevent symptomatic COVID-19 (and deaths) in 2022. We projected Evusheld intervention costs, quality-adjusted life year (QALY) lost, cost averted and QALY gained by reduced COVID-19 incidence, and incremental cost-effectiveness (cost per QALY gained) in each modeled population from the healthcare system perspective. RESULTS: Our study demonstrated that Evusheld treatment for COVID-19 infection in South Korea is highly cost-effective for unvaccinated risk groups ($18,959 per QALY gained for immunocompromised and $23,978 per QALY gained for high-risk elderly groups) and moderately cost-effective among individuals who are vaccinated immunocompromised ($46,494 per QALY gained), or have severe allergic reactions ($45,996 per QALY gained). Evusheld's cost-effectiveness may be subject to risk-group-specific COVID-19 disease progression and Evusheld efficacy and cost, which may change in future epidemic scenarios. CONCLUSION: As the COVID-19 variants and risk group-specific durable efficacy, toxicity (and/or resistance) and optimal dosing of Evusheld remain uncertain, better empirical estimates to inform these values in different epidemiological contexts are needed. These results may help decision-makers prioritize resources toward more equitable and effective COVID-19 control efforts.

Preparations for the Assessment of COVID-19 Infection and Long-Term Cardiovascular Risk.

Studies showing that coronavirus disease 2019 (COVID-19) is associated with an increased risk of cardiovascular disease continue to be published. However, studies on how long the overall cardiovascular risk increases after COVID-19 and the magnitude of its long-term effects have only been confirmed recently. This is partly because the distinction between cardiovascular risk as an acute complication of COVID-19 or post-acute cardiovascular manifestations is ambiguous. Long-COVID has arisen as an important topic in the second half of the pandemic. This term indicates that symptoms persist for more than two 2 months; following three months of SARS-CoV-2 infection and cannot be explained by other medical conditions. Despite the agreement of these international organizations and experts, it is difficult to define whether there is sufficient medical evidence to prove the existence of long-COVID. However, the Korean government and Korea Disease Control and Prevention Agency (KDCA) are preparing a new platform to assess the long-term impact of COVID-19. Using this data, a prospective cohort of 10,000 confirmed COVID-19 cases will be established. This cohort will be linked with claims data from the National Health Insurance Services (NHIS) and it is expected that increased real-world evidence of long-COVID will be accumulated.

Model-based cost-effectiveness analysis of oral antivirals against SARS-CoV-2 in Korea.

OBJECTIVES: Many countries have authorized the emergency use of oral antiviral agents for patients with mild-to-moderate cases of coronavirus disease 2019 (COVID-19). We assessed the cost-effectiveness of these agents for reducing the number of severe COVID-19 cases and the burden on Korea's medical system. METHODS: Using an existing model, we estimated the number of people who would require hospital/intensive care unit (ICU) admission in Korea in 2022. The treatment scenarios included (1) all adult patients, (2) elderly patients only, and (3) adult patients with underlying diseases only, compared to standard care. Based on the current health system capacity, we calculated the incremental costs per severe case averted and hospital admission for each scenario. RESULTS: We estimated that 236,510 COVID-19 patients would require hospital/ICU admission in 2022 with standard care only. Nirmatrelvir/ritonavir (87% efficacy) was predicted to reduce this number by 80%, 24%, and 17% when targeting all adults, adults with underlying diseases, and elderly patients (25, 8, and 4%, respectively, for molnupiravir, with 30% efficacy). Nirmatrelvir/ritonavir use is likely to be cost-effective, with predicted costs of US$8,878, US$8,964, and US$1,454, per severe patient averted for the target groups listed above, respectively, while molnupiravir is likely to be less cost-effective, with costs of US$28,492, US$29,575, and US$7,915, respectively. CONCLUSIONS: In Korea, oral treatment using nirmatrelvir/ritonavir for symptomatic COVID-19 patients targeting elderly patients would be highly cost-effective and would substantially reduce the demand for hospital admission to below the capacity of the health system if targeted to all adult patients instead of standard care.

Correlation between the Level of Social Distancing and Activity of Influenza Epidemic or COVID-19 Pandemic: A Subway Use-Based Assessment.

Social distancing is an effective measure to mitigate the spread of novel viral infections in the absence of antiviral agents and insufficient vaccine supplies. Subway utilization density may reflect social activity and the degree of social distancing in the general population.; This study aimed to evaluate the correlations between subway use density and the activity of the influenza epidemic or coronavirus disease 2019 (COVID-19) pandemic using a time-series regression method. The subway use-based social distancing score (S-SDS) was calculated using the weekly ridership of 11 major subway stations. The temporal association of S-SDS with influenza-like illness (ILI) rates or the COVID-19 pandemic activity was analyzed using structural vector autoregressive modeling and the Granger causality (GC) test. During three influenza seasons (2017-2020), the time-series regression presented a significant causality from S-SDS to ILI (p = 0.0484). During the COVID-19 pandemic in January 2020, S-SDS had been suppressed at a level similar to or below the average of the previous four years. In contrast to the ILI rate, there was a negative correlation between COVID-19 activity and S-SDS. GC analysis revealed a negative causal relationship between COVID-19 and S-SDS (p = 0.0098).; S-SDS showed a significant time-series association with the ILI rate but not with COVID-19 activity. When public transportation use is sufficiently suppressed, additional social mobility restrictions are unlikely to significantly affect COVID-19 pandemic activity. It would be more important to strengthen universal mask-wearing and detailed public health measures focused on risk activities, particularly in enclosed spaces.

Associations Between Private Health Insurance and Medical Care Utilization for Musculoskeletal Disorders: Using the Korea Health Panel Survey Data for 2014 to 2015.

In South Korea, people may increase their medical coverage by purchasing private health insurance to augment low coverage provided by the National Health Insurance (NHI). Frequent and excessive use of medical care by those with private health insurance is an issue, especially for musculoskeletal disorders that require excessive care and contribute to moral hazard. In South Korea, since private health insurance is structurally linked to the scope of coverage with public health insurance, this increased use of medical care may adversely affect public health insurance finances. This study aimed to analyze the effects of private health insurance on medical care use for patients with musculoskeletal disorders. We used the Korea Health Panel 2014 to 2015 data that included 5622 participants who used medical care for musculoskeletal disorders in 2015. Two groups were created: those who purchased private health insurance (n = 3588) and those without private insurance (n = 2034). We compared their medical utilization using logistic regression, negative binomial regression, and multiple linear regression to determine the associations of private health insurance with medical care use. Medical expenditures by private health insurance purchasers were higher than those of non-purchasers for outpatient care (P < .001), but no differences were found for inpatient care. Our findings suggest that the expansion of private health insurance further burdened the NHI financially, ultimately increasing the burden of medical expenses for the population. Research should implement demonstration studies with different groups of diseases.

Burden of dental caries and periodontal disease in South Korea: An analysis using the national health insurance claims database.

OBJECTIVES: It is essential to measure and monitor the burden of dental caries and periodontal disease (PD) in Korea's ageing population due to their potential impact on morbidity, quality of life and economic condition. This study aimed to quantify the size of burden of dental caries and PD using the disability-adjusted life years (DALYs), and their trends. METHODS: DALYs were estimated using incidence-based approaches to calculate the burden of dental caries and PD from 2013 to 2015 in Korea. Incidence and prevalence were estimated using medical claim data by specific algorithms. Additionally, sensitivity analysis was conducted to investigate possible weakness in the study methodology. To conduct the sensitivity analysis, we modified the algorithms to estimate prevalence and incidence. RESULTS: The burden of dental caries and PD increased by 39.2% and 57.0%, respectively, between 2013 and 2015. In 2015, dental caries and PD ranked 11th and 25th, respectively, in terms of the leading causes of DALYs. The burden of dental caries was the most substantial in children aged 0-9 years, while that of PD was the most substantial among those in their ages of 40 and 50 (per 100 000 population). After sensitivity analysis with a modified disease algorithm, the magnitude of disease burden changed considerably. CONCLUSIONS: Dental caries and PD constitute substantial burdens in South Korea. Despite the known limitations, medical claims data can be a powerful resource for conducting timely and cost-effective measurements of oral health. In countries, where universal dental schemes are available, there is need to estimate the burden of oral disease using claims data, for methodical advances in the research field.

Complementing conventional infectious disease surveillance with national health insurance claims data in the Republic of Korea.

Surveillance remains an important tool for timely outbreak detection and response. Many countries, including Korea, have established national infectious disease surveillance systems with clinical notification. We aimed to evaluate the National Health Insurance Claims-based Surveillance (NHICS) compared to conventional passive report-based National Infectious Diseases Surveillance (NIDS). Reported to claimed cases ratios (R/C ratio) were evaluated from monthly notifiable disease cases captured by NIDS and NHICS. The relationships between 26 infectious diseases and each surveillance system were analysed using Pearson's correlation analysis and linear regression. There was an overall increase in R/C ratio from 2010-2017 (0.37 to 0.78). In 22 infectious diseases, there was a correlation between NIDS and NHICS. Moreover, claim-based surveillance showed less fluctuating disease incidence rates than report-based surveillance for specific infectious diseases, such as varicella, mumps, and scarlet fever. However, for infectious diseases with episodic outbreaks or low incidence, it was difficult to assess NHICS usefulness. Claim-based surveillance is less affected by limitations of conventional report-based surveillance systems, such as reporting rate. Given delays in claim systems, a claim-based surveillance is expected to be complementary to conventional systems for the detection of various infectious diseases with the advancement of bio-information technology.

Trends and Patterns of Burden of Disease and Injuries in Korea Using Disability-Adjusted Life Years.

BACKGROUND: It is extremely important to objectively take a view of population health to provide useful information to decision makers, health-sector leaders, researchers, and informed citizens. This study aims to examine the burden of disease in Korea as of 2015, and to study how the burden of disease changes with the passage of time. METHODS: We used results from the Korean National Burden of Disease and Injuries Study 2015 for all-cause mortality, cause-specific mortality, and non-fatal disease burden to derive disability-adjusted life years (DALYs) by gender and age groups from 2007 to 2015. DALYs were calculated as the sum of the years of life lost (YLLs) and the years lived with disability (YLDs). RESULTS: In 2015, the burden of disease for Korean people was calculated at 29,476 DALYs per 100,000 population. DALYs caused by low back pain were the highest, followed by diabetes mellitus and chronic obstructive pulmonary disease. The burden of disease showed a consistently increasing trend from 2007 to 2015. Although YLLs have been on the decrease since 2011, the increase in YLDs has contributed to the overall rise in DALYs. The DALYs per 100,000 population in 2015 increased by 28.1% compared to 2007. CONCLUSION: As for the diseases for which the burden of disease is substantially increasing, it is needed to establish appropriate policies in a timely manner. The results of this study are expected to be the basis for prioritizing public health and health care policies in Korea.

Regional Differences in Years of Life Lost in Korea from 1997 to 2015.

BACKGROUND: Reducing the gaps in health inequality at a regional level and improving health equity have been emphasized in Korea, it is essential to accurately measure the burden of disease by region. This study aimed to estimate years of life lost (YLLs) in 17 Si and Do of Korea from 1997 to 2015 and determine the trends of regional differences in health status and disease structure. METHODS: YLL was calculated by subtracting the age at death from the life expectancy. Data on the region, gender, and age-stratified cause-specific death were obtained from the Korean Statistical Information Service of Statistics Korea. RESULTS: Age-standardized YLLs per 100,000 population decreased by year in all regions from 1997 to 2015 by 27.4% (27.5% for men; 27.2% for women). Despite the decline in YLLs, the regions with the highest and lowest YLLs did not change between 1997 and 2015. The diseases showing regional differences were caused by injury, often classified as avoidable mortality. We also confirmed that YLLs were higher in the regions with a higher deprivation index. CONCLUSION: The present study identified that YLLs differed by regions in Korea with specific causes. The findings of this study can be used by decision-makers to prioritize the reduction of regional gaps in premature deaths.

Epidemiological Impact of the Korean National Immunization Program on Varicella Incidence.

The number of reported varicella cases is continuously increasing in Korea; however, associated medical utilization is declining. The ratio between varicella insurance claims and reports of passive infectious disease surveillance has gradually increased to > 80% since the second half of 2017. The recent increase in reported varicella cases is influenced by improved reporting. We calculated the varicella incidence and cumulative incidence in each birth cohort according to age. The cumulative incidence rate among children aged < 6 years in the birth cohort born after the National Immunization Program introduced the varicella vaccine was about 60% lower than among children born before.

Malaria control and chemoprophylaxis policy in the Republic of Korea Armed Forces for the previous 20 years (1997-2016).

BACKGROUND: Vivax malaria reemerged along the Demilitarized Zone (DMZ), Republic of Korea (ROK), in 1993. While it was hypothesized that vivax malaria would spread throughout the peninsula, nearly all cases were due to exposure near the DMZ. To reduce spillover of vivax malaria to the civilian community, the ROK Ministry of National Defense (MND) initiated malaria prevention policies including a large-scale chemoprophylaxis programme in malaria high-risk areas in 1997. The present study investigated the overall changes in the incidence of malaria among ROK soldiers and the mass chemoprophylaxis program from 1997 to 2016. RESULTS: Peak numbers of vivax malaria were reported in 2000, with most cases reported near the DMZ, before declining to the current levels. To combat the rapid increase in the number of malaria cases and its expansion throughout the ROK, the MND implemented mosquito control and personal protection programmes. The MND also implemented a large-scale vivax malaria chemoprophylaxis programme using hydroxychloroquine (400 mg weekly) in 1997, and primaquine (15 mg × 14 days) as terminal chemoprophylaxis in 2001. Additionally, an improved medical system enabled the rapid detection and treatment of malaria to reduce morbidity and decrease transmission of malaria from humans to mosquitoes. Following the full implementation of these programmes, the incidence of vivax malaria declined in both ROK Armed Forces and civilian populations. Subsequently, several changes in the ROK Armed Forces chemoprophylaxis programme were implemented, including the reduction of the period of hydroxychloroquine prophylaxis by 2 months (2008) and other changes in the chemoprophylaxis policy, e.g., only ROK Armed Forces personnel in moderate risk groups received terminal primaquine chemoprophylaxis (2011), and in 2016, the discontinuation of terminal primaquine chemoprophylaxis in moderate-risk area. CONCLUSIONS: The resurgence of vivax malaria in the ROK Armed Forces personnel near the DMZ was successfully suppressed through the implementation of a mass malaria chemoprophylaxis programme initiated by the MND in 1997, as well as several other factors that may have contributed to the reduction of malaria transmission since 2000. Given the current malaria situation in the ROK and North Korea, it is necessary to reevaluate the ROK Armed Forces and civilian malaria control policies.

The economic burden of epilepsy in Korea, 2010.

OBJECTIVES: The purposes of this study were to evaluate the prevalence of epilepsy and to estimate the cost of epilepsy in Korea, 2010. METHODS: This study used a prevalence based approach to calculate the cost of epilepsy. Claims data from the Korean national health insurance and data from the Korea health panel, the Korea National Statistical Office's records of causes of death, and labor statistics were used to estimate the cost of epilepsy. Patients were defined as those who were hospitalized or visited an outpatient clinic during 2010 with a diagnosis of epilepsy (International Classification of Diseases 10th revision codes G40-G41). Total costs of epilepsy included direct medical costs, direct non-medical cost and indirect costs. RESULTS: The annual prevalence of treated epilepsy was 228 per 100 000 population, and higher in men. The age-specific prevalence was highest for teenagers. The total economic burden of epilepsy was 536 billion Korean won (KW). Indirect cost (304 billion KW) was 1.3 times greater than direct cost (232 billion KW). By gender, the male (347 billion KW) were more burdened than the female (189 billion KW). The estimated cost in young age younger than 20 years old was 24.5% of the total burden of epilepsy. CONCLUSIONS: A significant portion of the economic burden of epilepsy is borne by people in young age. To reduce the economic burden of epilepsy, effective prevention and treatment strategies are needed.