1
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Lee YH, Choe YJ. A cost benefit analysis of varicella vaccination in South Korea. Vaccine X 2024; 19:100521. [PMID: 39070929 PMCID: PMC11277761 DOI: 10.1016/j.jvacx.2024.100521] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2024] [Revised: 07/02/2024] [Accepted: 07/03/2024] [Indexed: 07/30/2024] Open
Abstract
Background The introduction of varicella vaccination has significantly reduced the burden of chickenpox in many countries, but outbreaks still occur in populations with high vaccination coverage. To address this, some countries, including the United States, Germany, and Japan, have adopted a two-dose varicella vaccination recommendation. Economic evaluations are crucial for assessing vaccine recommendations; however, there are limited studies exist in Asian countries. Thus, our study aimed to evaluate the cost-benefit of one-dose and two-dose varicella vaccination programs compared to no vaccination in South Korea, incorporating updated data on disease burden and costs. Methods We utilized data from South Korea's health databases to estimate varicella burden and vaccination records. Decision tree analysis was employed to compare costs and benefits of vaccination strategies over a ten-year period for the 2012 birth cohort. Sensitivity analyses were conducted to assess the impact of various variables. Results Both one-dose and two-dose vaccination programs showed cost-benefit compared to no vaccination, with substantial societal cost savings. The one-dose program yielded a benefit-cost ratio (BCR) of1.43, while the two-dose program had a direct BCR of1.28. Sensitivity analyses confirmed the robustness of these findings. Conclusion Our study demonstrates the economic benefits of varicella vaccination in South Korea, aligning with findings from other countries. While the second dose did not show additional cost savings compared to the one-dose program, other factors like disease severity and transmission dynamics should be considered. Implementing either a one-dose or two-dose varicella vaccination regimen in South Korea could lead to cost reductions and improved cost-effectiveness compared to no vaccination, emphasizing the importance of vaccination programs in reducing disease burden and enhancing public health outcomes.
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Affiliation(s)
- Young Hwa Lee
- Allergy Immunology Center, Korea University, Seoul, the Republic of Korea
| | - Young June Choe
- Allergy Immunology Center, Korea University, Seoul, the Republic of Korea
- Department of Pediatrics, Korea University College of Medicine and Korea University Anam Hospital, Seoul, the Republic of Korea
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2
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Lee YH, Choe YJ, Lee J, Kim E, Lee JY, Hong K, Yoon Y, Kim YK. Global varicella vaccination programs. Clin Exp Pediatr 2022; 65:555-562. [PMID: 36457198 PMCID: PMC9742762 DOI: 10.3345/cep.2021.01564] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/15/2021] [Accepted: 03/11/2022] [Indexed: 11/09/2022] Open
Abstract
Varicella (chickenpox) is an infectious disease caused by the highly contagious varicella zoster virus with a secondary attack rate greater than 90%. From this perspective, we aimed to establish the basis for a national varicella vaccine policy by reviewing vaccination programs and policies of countries that have introduced universal varicella vaccinations. As a result of the spread of varicella, an increasing number of countries are providing 2-dose vaccinations and universally expanding their use. In practice, the efficacy and effectiveness of vaccination differ among vaccines and vaccination programs. Optimized vaccination strategies based on each country's local epidemiology and health resources are required. Accordingly, it is necessary to evaluate the effectiveness of varicella vaccines in different settings. Given the short-term and fragmented vaccine effectiveness evaluation in Korea, it is necessary to evaluate its effectiveness at the national level and determine its schedule based on the evidence generated through these studies.
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Affiliation(s)
- Young Hwa Lee
- Department of Pediatrics, Korea University Anam Hospital, Seoul, Korea
| | - Young June Choe
- Department of Pediatrics, Korea University Anam Hospital, Seoul, Korea
| | - Jia Lee
- Division of Immunization, Korea Disease Control and Prevention Agency, Cheongju, Korea
| | - Eunseong Kim
- Division of Immunization, Korea Disease Control and Prevention Agency, Cheongju, Korea
| | - Jae Young Lee
- Division of Immunization, Korea Disease Control and Prevention Agency, Cheongju, Korea
| | - Kwan Hong
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
| | - Yoonsun Yoon
- Department of Pediatrics, Korea University Guro Hospital, Seoul, Korea
| | - Yun-Kyung Kim
- Department of Pediatrics, Korea University Ansan Hospital, Ansan, Korea.,Korea University College of Medicine, Seoul, Korea
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3
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Suh J, Choi JK, Lee J, Park SH. Estimation of single-dose varicella vaccine effectiveness in South Korea using mathematical modeling. Hum Vaccin Immunother 2022; 18:2085468. [PMID: 35704399 PMCID: PMC9621034 DOI: 10.1080/21645515.2022.2085468] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/25/2022] Open
Abstract
In South Korea, despite the implementation of a universal single-dose vaccination program for children aged 12–15 months in 2005, the varicella incidence rate remains significant. Prior case-control studies have reported that currently used varicella vaccines are extremely inefficacious. We estimated vaccine effectiveness (VE) by fitting a dynamic transmission model to age-specific varicella incidence data from 2007 to 2015 and available vaccine coverage data. The initial vaccine efficacy and primary failure rates were estimated to be 61.1% and 38.9%, respectively. The average duration of protection was 21.4 years. The mean VE [(1-relative risk) %] for the simulated data of 2004–2014 birth cohorts decreased from 59.8% to 50.7% over 9 years. This mathematical modeling study demonstrated that the single-dose vaccine exhibits moderate effectiveness, and a high proportion of primary failure could be a main cause of breakthrough infections. Therefore, a two-dose vaccination strategy should be considered.
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Affiliation(s)
- Jiyeon Suh
- School of Mathematics and Computing (Computational Science and Engineering), Yonsei University, Seoul, Republic of Korea
| | - Jae-Ki Choi
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jeehyun Lee
- School of Mathematics and Computing, Yonsei University, Seoul, Republic of Korea
| | - Sun Hee Park
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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4
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Kim EY, Park C, Lee G, Jeong S, Song J, Lee DH. Epidemiological characteristics of varicella outbreaks in the Republic of Korea, 2016–2020. Osong Public Health Res Perspect 2022; 13:133-141. [PMID: 35538685 PMCID: PMC9091637 DOI: 10.24171/j.phrp.2022.0087] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/15/2022] [Accepted: 04/04/2022] [Indexed: 11/10/2022] Open
Abstract
Objectives We described the trends and epidemiological characteristics of varicella outbreaks from 2016 to 2020 in the Republic of Korea. Methods We investigated variables such as the outbreak setting, age of patients, vaccination status, and lesion count. The collected data were analyzed with the Cochrane-Armitage trend test and Kruskal-Wallis test. These statistical tests were performed using R ver. 4.0.3. Results The number of varicella outbreaks increased from 2016 to 2018; however, after a slight decrease in the number of outbreaks in 2019, the number fell sharply in 2020. The median size of outbreaks decreased from 8 to 9 cases during 2016−2019 to 6 cases in 2020. The median duration of outbreaks was 18 days during 2016−2017, 28 days in 2018, 29 days in 2019, and 15 days in 2020. Varicella outbreaks occurred most frequently in elementary schools, and vaccination coverage of patients increased from 89.4% in 2016 to 97.2% in 2019. The median age of patients with outbreak-related varicella decreased from 8 years in 2016 to 6 years in 2020. Conclusion Significant changes were observed in the age of patients with outbreak-related varicella. Ongoing monitoring of varicella outbreaks should be conducted. Further research will be needed to measure the disease burden of varicella and enable evidence-based policy decisions.
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5
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Choi B, Kwon S. Seroprevalence comparison of different varicella vaccines among Turkish children. Hum Vaccin Immunother 2022; 18:2067443. [PMID: 35446747 PMCID: PMC9302503 DOI: 10.1080/21645515.2022.2067443] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/02/2022] Open
Affiliation(s)
- BongKyoo Choi
- Department of Research and Development, GC Pharma, Yongin, South Korea.,Department of Biohealth Regulatory Science, Sungkyunkwan University, Suwon, South Korea
| | - ShiNae Kwon
- Department of Research and Development, GC Pharma, Yongin, South Korea
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6
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Choi B, Cho H, Shin Y, Lee EK. Letter to the Editor: Effectiveness of the Varicella Vaccine Among Korean Children: Suggestions for Future Research. J Korean Med Sci 2022; 37:e17. [PMID: 34981684 PMCID: PMC8723895 DOI: 10.3346/jkms.2022.37.e17] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2021] [Accepted: 12/22/2021] [Indexed: 11/26/2022] Open
Affiliation(s)
- BongKyoo Choi
- Department of Research and Development, GC Pharma, Yongin, Korea
- Department of Medicine, University of California, Irvine, CA, USA
- Department of Biohealth Regulatory Science, Sungkyunkwan University, Suwon, Korea.
| | - Hyunjeong Cho
- Department of Research and Development, GC Pharma, Yongin, Korea
| | - Younchul Shin
- Department of Research and Development, GC Pharma, Yongin, Korea
| | - Eun-Kyoung Lee
- Department of Research and Development, GC Pharma, Yongin, Korea
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7
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Lee YH, Choe YJ, Hwang SS, Cho SI. Spatiotemporal distribution of varicella in the Republic of Korea. J Med Virol 2021; 94:703-712. [PMID: 34738261 DOI: 10.1002/jmv.27434] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/30/2021] [Revised: 10/28/2021] [Accepted: 11/02/2021] [Indexed: 11/10/2022]
Abstract
Varicella is a highly contagious disease caused by the varicella-zoster virus (VZV). Given its tendency to cluster geographically, spatial analyses may provide a better understanding of the pattern of varicella transmission. We investigated the spatial characteristics of varicella in Korea and the risk factors for varicella at a national level. Using national surveillance and demographic data, we examined the spatial distribution of incidence rates and their spatial autocorrelation and calculated Moran's index. Spatial regression analysis was used to identify sociodemographic predictors of varicella incidence at the district level. An increasing tendency in the annual incidence of varicella was observed over a 12-year period (2006-2018), with a surge in 2017. There was a clear positive spatial autocorrelation of the varicella incidence rate during the surveillance period. During 2006-2014, High-High (HH) clusters were mostly confined to the northeast region and neighboring districts. The spatial error model showed that population density had a negative coefficient and childhood percentage, percentage of children under 12 years of age among the total population, had positive coefficient, whereas vaccine coverage was insignificant. The varicella incidence according to geographic region varied with population density, childhood percentage, suggesting the importance of community-level surveillance and monitoring strategies.
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Affiliation(s)
- Young Hwa Lee
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, Republic of Korea.,Department of Pediatrics, Korea University Anam Hospital, Seoul, Republic of Korea
| | - Young June Choe
- Department of Pediatrics, Korea University Anam Hospital, Seoul, Republic of Korea
| | - Seung-Sik Hwang
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, Republic of Korea
| | - Sung-Il Cho
- Department of Epidemiology, School of Public Health, Seoul National University, Seoul, Republic of Korea
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8
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Umit Z, Sahbudak Bal Z, Zeytinoglu A, Gulbahar Aydogan T, Bag O, Guner Ozenen G, Ozkinay F, Kurugol Z. The comparison of seroconversion rates among different varicella vaccines administered Turkish children; MAV/06 and vOka. Hum Vaccin Immunother 2021; 17:4190-4193. [PMID: 34643479 DOI: 10.1080/21645515.2021.1967037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/20/2022] Open
Abstract
Varicella is a vaccine-preventable disease, and the incidence of varicella has declined since the introduction of varicella vaccine campaigns. A wild type of varicella zoster virus (VZV) was isolated from a 33-month-old child with varicella in Korea in 1989, a different strain (MAV/06). A live-attenuated varicella vaccine containing strain (MAV/06), Suduvax®, was developed in South Korea in 1994. Turkey introduced the varicella vaccine containing the MAV/06 strain (Varicella Vaccine-GCC, Green Cross, South Korea) in January 2019. Therefore, we aimed to compare the seroconversion rates among MAV/06 vaccine- and vOka-administered children. We prospectively collected blood samples from 98 received vOKA and 98 received MAV/06 children 6 weeks after administration, and seroconversion rates were determined by an indirect fluorescence assay (Anti-VZV IIFT IgG, Euroimmun, Germany). Seroconversion rate was significantly higher in vOka group than MAV/06 group (82.7% vs. 64.3%; p = .004). Of the children vaccinated with vOka strain, 17 children did not develop antibodies, 12 were weakly positive, and the remaining 69 children were strongly positive. Of the children who were administered MAV/06 strain, 35 were negative, 20 were weakly positive, and 43 were strongly positive. In conclusion, this study demonstrated that MAV/06 varicella vaccine had lower seroconversion rates and the strong seropositive cases were less common than vOka-administered children. Larger and prospective studies are needed.
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Affiliation(s)
- Zuhal Umit
- Division of Infectious Disease, Department of Pediatrics, Medical School of Ege University, Izmir, Turkey
| | - Zumrut Sahbudak Bal
- Division of Infectious Disease, Department of Pediatrics, Medical School of Ege University, Izmir, Turkey
| | - Aysin Zeytinoglu
- Department of Medical Microbiology, Ege University Faculty of Medicine, İzmir, Turkey
| | | | - Ozlem Bag
- Departments of Social Pediatrics, Dr Behcet Uz 'Children's Hospital, Izmir, Turkey
| | - Gizem Guner Ozenen
- Division of Infectious Disease, Department of Pediatrics, Medical School of Ege University, Izmir, Turkey
| | - Ferda Ozkinay
- Division of Infectious Disease, Department of Pediatrics, Medical School of Ege University, Izmir, Turkey
| | - Zafer Kurugol
- Division of Infectious Disease, Department of Pediatrics, Medical School of Ege University, Izmir, Turkey
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9
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Carryn S, Cheuvart B, Povey M, Dagnew AF, Harpaz R, van der Most R, Casabona G. No consistent evidence of decreased exposure to varicella-zoster virus among older adults in countries with universal varicella vaccination. J Infect Dis 2021; 225:413-421. [PMID: 34609490 PMCID: PMC8807177 DOI: 10.1093/infdis/jiab500] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2021] [Accepted: 10/04/2021] [Indexed: 11/16/2022] Open
Abstract
Background Universal varicella vaccination might reduce opportunities for varicella-zoster virus (VZV) exposure and protective immunological boosting, thus increasing herpes zoster incidence in latently infected adults. We assessed humoral and cell-mediated immunity (CMI), as markers of VZV exposure, in adults aged ≥50 years. Methods We repurposed data from placebo recipients in a large multinational clinical trial (ZOE-50). Countries were clustered based on their varicella vaccination program characteristics, as having high, moderate, or low VZV circulation. Anti-VZV antibody geometric mean concentrations, median frequencies of VZV-specific CD4 T cells, and percentages of individuals with increases in VZV-specific CD4 T-cell frequencies were compared across countries and clusters. Sensitivity analyses using a variable number of time points and different thresholds were performed for CMI data. Results VZV-specific humoral immunity from 17 countries (12 high, 2 moderate, 3 low circulation) varied significantly between countries (P < .0001) but not by VZV circulation. No significant differences were identified in VZV-specific CMI between participants from 2 high versus 1 low circulation country. In 3/5 sensitivity analyses, increases in CMI were more frequent in high VZV circulation countries (.03 ≤ P < .05). Conclusions We found no consistent evidence of reduced VZV exposure among older adults in countries with universal varicella vaccination. Clinical Trials Registration NCT01165177.
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Affiliation(s)
| | | | | | - Alemnew F Dagnew
- GSK, 14200 Shady Grove Road, Rockville, MD, USA.,Bill & Melinda Gates Medical Research Institute, Cambridge, MA, USA
| | | | - Robbert van der Most
- GSK, Rue de l'Institut, Rixensart, Belgium.,Coalition for Epidemic Preparedness Innovations (CEPI), 0473 Oslo, Norway
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10
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Hong K, Sohn S, Choe YJ, Rhie K, Lee JK, Han MS, Chun BC, Choi EH. Waning Effectiveness of One-dose Universal Varicella Vaccination in Korea, 2011-2018: a Propensity Score Matched National Population Cohort. J Korean Med Sci 2021; 36:e222. [PMID: 34519184 PMCID: PMC8438188 DOI: 10.3346/jkms.2021.36.e222] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/06/2021] [Accepted: 07/25/2021] [Indexed: 01/21/2023] Open
Abstract
BACKGROUND Despite high coverage (~98%) of universal varicella vaccination (UVV) in the Republic of Korea since 2005, reduction in the incidence rate of varicella is not obvious. The study aimed to evaluate the vaccine effectiveness (VE) of one-dose UVV by timeline and severity of the disease. METHODS All children born in Korea in 2011 were included for this retrospective cohort study that analyzed insurance claims data from 2011-2018 and the varicella vaccination records in the immunization registry. Adjusted hazard ratios by Cox proportional hazard models were used to estimate the VE through propensity score matching by the month of birth, sex, healthcare utilization rate, and region. RESULTS Of the total 421,070 newborns in the 2011 birth cohort, 13,360 were matched for age, sex, healthcare utilization rate, and region by the propensity score matching method. A total of 55,940 (13.29%) children were diagnosed with varicella, with the incidence rate 24.2 per 1000 person-year; 13.4% of vaccinated children and 10.4% of unvaccinated children. The VE of one-dose UVV against any varicella was 86.1% (95% confidence interval [CI], 81.4-89.5) during the first year after vaccination and 49.9% (95% CI, 43.3-55.7) during the 6-year follow-up period since vaccination, resulting in a 7.2% annual decrease of VE. The overall VE for severe varicella was 66.3%. The VE of two-dose compared to one-dose was 73.4% (95% CI, 72.2-74.6). CONCLUSION We found lower long-term VE in one-dose vaccination and waning of effectiveness over time. Longer follow ups of the vaccinated children as well as appropriately designed studies are needed to establish the optimal strategy in preventing varicella in Korea.
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Affiliation(s)
- Kwan Hong
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
| | - Sangho Sohn
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
| | - Young June Choe
- Department of Pediatrics, Korea University Anam Hospital, Seoul, Korea
| | - Kyuyol Rhie
- Department of Pediatrics, Incheon Sejong Hospital, Incheon, Korea
| | - Joon Kee Lee
- Department of Pediatrics, Chungbuk National University Hospital, Cheongju, Korea
| | - Mi Seon Han
- Department of Pediatrics, Seoul Metropolitan Government - Seoul National University Boramae Medical Center, Seoul, Korea
| | - Byung Chul Chun
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
| | - Eun Hwa Choi
- Department of Pediatrics, Seoul National University Hospital, Seoul, Korea
- Department of Pediatrics, Seoul National University Hospital, Seoul, Korea.
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11
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Choi B, Shin JH, Lee JE, Koh SB. Letter to the Editor: Effectiveness of the Varicella Vaccine in Korea: Unresolved Issues. J Korean Med Sci 2021; 36:e200. [PMID: 34254478 PMCID: PMC8275458 DOI: 10.3346/jkms.2021.36.e200] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/05/2021] [Accepted: 07/01/2021] [Indexed: 11/20/2022] Open
Affiliation(s)
- BongKyoo Choi
- Department of Research and Development, GC Pharma, Yongin, Korea
- Department of Medicine, University of California, Irvine, CA, USA.
| | - Ji Hyeun Shin
- Department of Pharmacovigilance, LSK Global PS, Seoul, Korea
| | - Jee Eun Lee
- Department of Clinical and Regulatory Affairs, LG Chem Ltd, Seoul, Korea
| | - Sang Baek Koh
- Department of Preventive Medicine, Wonju College of Medicine, Yonsei University, Wonju, Korea
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12
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Cross-Sectional Study of Varicella Zoster Virus Immunity in Healthy Korean Children Assessed by Glycoprotein Enzyme-Linked Immunosorbent Assay and Fluorescent Antibody to Membrane Antigen Test. Vaccines (Basel) 2021; 9:vaccines9050492. [PMID: 34065863 PMCID: PMC8151998 DOI: 10.3390/vaccines9050492] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 05/05/2021] [Accepted: 05/07/2021] [Indexed: 11/17/2022] Open
Abstract
The prevalence of varicella is especially high among children in the age group of 4-6 years in South Korea, regardless of vaccination. We investigated the immune status of healthy children enrolled in day-care centers and compared pre- and post-vaccination immunity. Antibody titers were measured using a glycoprotein enzyme-linked immunosorbent assay (gpEIA) kit, and the seroconversion rate was assessed using a fluorescent antibody to membrane antigen (FAMA) test. Among 541 vaccinated children, 109 (20.1%) had breakthrough varicella. However, 13 (72.2%) of the 18 unvaccinated children had a history of varicella. The gpEIA geometric mean titers (GMTs) of pre- and 5 weeks post-vaccination in 1-year-old children were 14.7 and 72 mIU/mL, respectively, and the FAMA seroconversion rate was 91.1%. The gpEIA GMTs of 2-, 3-, 4-, 5-, and 6-year-old children were 104.1, 133.8, 223.5, 364.1, and 353.0 mIU/mL, respectively. Even though the gpEIA GMT increased with age, the pattern of gpEIA titer distribution in 4- to 6-year-old vaccinees without varicella history represented both waning immunity and natural boosting immunity. These results suggest that some vaccinees are vulnerable to varicella infection. Therefore, it is necessary to consider a two-dose varicella vaccine regimen in South Korea.
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13
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Suh J, Lee T, Choi JK, Lee J, Park SH. The impact of two-dose varicella vaccination on varicella and herpes zoster incidence in South Korea using a mathematical model with changing population demographics. Vaccine 2021; 39:2575-2583. [PMID: 33814230 DOI: 10.1016/j.vaccine.2021.03.056] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 03/13/2021] [Accepted: 03/16/2021] [Indexed: 01/29/2023]
Abstract
BACKGROUND In South Korea, one-dose varicella vaccination was introduced to the National Immunization Program in 2005, but varicella outbreaks have continued to occur. Therefore, a two-dose vaccination strategy is considered. METHODS We developed an age-structured deterministic compartment model using Korean population projection data. The impact of adding a second dose of varicella vaccine on varicella and herpes zoster (HZ) epidemiology was assessed under four different vaccine effectiveness (VE) scenarios (base, moderate, lowest, highest) and the optimal timing of the second vaccine dose (18 months, 4, 5, or 6 years of age) was examined over the period 2020-2065. RESULTS A two-dose vaccination schedule reduced the cumulative varicella incidence by > 90% compared to no vaccination, regardless of the VE. The additional reduction attributable to a second dose compared to a single dose was greatest (82%) with the lowest VE scenario. A second dose at 6 years of age reduced the varicella incidence at a population level, whereas a second dose at 18 months of age reduced the varicella incidence primarily in the target birth cohorts. Routine vaccination at the age of 18 months with a catch-up vaccination of 6-year-olds was the optimal strategy for birth cohort and population-level control. HZ incidence continued to increase under no vaccination scenario, which represents the effect of aging population. Under a two-dose scenario, the additional increase in HZ incidence attributable to the reduced exogenous boosting was small relative to a one-dose scenario and a further reduction in HZ cases was observed. CONCLUSION A two-dose varicella vaccination schedule would significantly reduce varicella and HZ incidence in the long term. A second dose at the age of 18 months with a catch-up vaccination of 6-year-olds would be optimal for controlling varicella in South Korea.
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Affiliation(s)
- Jiyeon Suh
- School of Mathematics and Computing (Computational Science and Engineering), Yonsei University, Seoul, Republic of Korea
| | - Taeyong Lee
- School of Mathematics and Computing (Mathematics), Yonsei University, Seoul, Republic of Korea
| | - Jae-Ki Choi
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jeehyun Lee
- School of Mathematics and Computing (Computational Science and Engineering), Yonsei University, Seoul, Republic of Korea; School of Mathematics and Computing (Mathematics), Yonsei University, Seoul, Republic of Korea.
| | - Sun Hee Park
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.
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14
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Choi B, Shin JH, Lee JE, Koh S. Letter to the Editor: Epidemiological Comments on the Effectiveness of the Varicella Vaccine in Korea. J Korean Med Sci 2020; 35:e265. [PMID: 32686377 PMCID: PMC7371459 DOI: 10.3346/jkms.2020.35.e265] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 02/17/2020] [Accepted: 05/25/2020] [Indexed: 12/12/2022] Open
Affiliation(s)
- BongKyoo Choi
- Department of Research and Early Development, GC Pharma, Yongin, Korea
- Department of Medicine, University of California, Irvine, CA, USA.
| | - Ji Hyeun Shin
- Department of Pharmacovigilance, LSK Global PS, Seoul, Korea
| | - Jee Eun Lee
- Department of Research and Early Development, GC Pharma, Yongin, Korea
| | - Sangbaek Koh
- Department of Preventive Medicine, Wonju College of Medicine, Yonsei University, Wonju, Korea
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15
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Lee YH, Choe YJ, Cho SI, Park HK, Bang JH, Lee JK. The Author's Response: Effects of One-dose Varicella Vaccination on Disease Severity in Children during Outbreaks in Seoul, Korea. J Korean Med Sci 2020; 35:e266. [PMID: 32686378 DOI: 10.3346/jkms.2020.35.e266] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/16/2020] [Accepted: 07/08/2020] [Indexed: 11/20/2022] Open
Affiliation(s)
- Young Hwa Lee
- Department of Social and Preventive Medicine, Hallym University College of Medicine, Chuncheon, Korea
| | - Young June Choe
- Department of Social and Preventive Medicine, Hallym University College of Medicine, Chuncheon, Korea
| | - Sung Il Cho
- Department of Epidemiology, Seoul National University Graduate School of Public Health, Seoul, Korea
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
| | - Hye Kyung Park
- Division of Infectious Disease Surveillance, Center for Control of Infectious Diseases, KCDC, Osong, Korea
| | - Ji Hwan Bang
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
- Division of Infectious Diseases, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea
| | - Jong Koo Lee
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
- Department of Family Medicine, Seoul National University College of Medicine, Seoul, Korea.
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16
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Graham J, Wolfson LJ, Kyle J, Bolde-Villarreal CP, Guarneros-DeRegil DB, Monsanto H, Pillsbury M, Talbird S, Daniels VJ. Budget impact analysis of multiple varicella vaccination strategies: a Mexico perspective. Hum Vaccin Immunother 2019; 16:886-894. [PMID: 31567045 PMCID: PMC7227656 DOI: 10.1080/21645515.2019.1672491] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
A number of live-attenuated varicella vaccines are produced globally that provide protection against the varicella zoster virus. In Mexico, varicella vaccination is not included in the national immunization program and is recommended for use only in high-risk subgroups. We developed a budget impact model to estimate the impact of universal childhood immunization against varicella on the national payer system in Mexico. A scenario of no varicella vaccination was compared to scenarios with vaccination with a single dose at 13 months of age, in alignment with the existing program of immunization with the measles-mumps-rubella vaccine. Nine different vaccination scenarios were envisioned, differing by vaccine type and by coverage. Varicella cases and treatment costs of each scenario were computed in a dynamic transmission model of varicella epidemiology, calibrated to the population of Mexico. Unit costs were based on Mexico sources or were from the literature. The results indicated that each of the three vaccine types increased vaccine acquisition and administration expenditures but produced overall cost savings in each of the first 10 years of the program, due to fewer cases and reduced varicella treatment costs. A highly effective vaccine at 95% coverage produced the greatest cost savings.
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Affiliation(s)
- Jonathan Graham
- Health Economics, Research Triangle Park, RTI Health Solutions, NC, USA
| | - Lara J Wolfson
- Center for Observational and Real World Evidence (CORE), Merck & Co., Inc, Kenilworth, NJ, USA
| | - Jeffrey Kyle
- Center for Observational and Real World Evidence (CORE), Merck & Co., Inc, Kenilworth, NJ, USA
| | | | | | | | - Matthew Pillsbury
- Center for Observational and Real World Evidence (CORE), Merck & Co., Inc, Kenilworth, NJ, USA
| | - Sandra Talbird
- Health Economics, Research Triangle Park, RTI Health Solutions, NC, USA
| | - Vincent J Daniels
- Center for Observational and Real World Evidence (CORE), Merck & Co., Inc, Kenilworth, NJ, USA
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17
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Cost-effectiveness analysis of universal varicella vaccination in Turkey using a dynamic transmission model. PLoS One 2019; 14:e0220921. [PMID: 31408505 PMCID: PMC6692038 DOI: 10.1371/journal.pone.0220921] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Accepted: 07/25/2019] [Indexed: 12/18/2022] Open
Abstract
BACKGROUND In 2013, Turkey introduced one-dose universal varicella vaccination (UVV) at 12 months of age. Inclusion of a second dose is being considered. METHODS We developed a dynamic transmission model to evaluate three vaccination strategies: single dose at 12 months (1D) or second dose at either 18 months (2D-short) or 6 years of age (2D-long). Costs and utilization were age-stratified and separated into inpatient and outpatient costs for varicella and herpes zoster (HZ). We ran the model including and excluding HZ-related costs and impact of exogenous boosting. RESULTS Five years post-introduction of UVV (1D), the projected varicella incidence rate decreases from 1,674 cases pre-vaccine to 80 cases/100,000 person-years. By 25 years, varicella incidence equilibrates at 39, 12, and 16 cases/100,000 person-years for 1D, 2D-short, and 2D-long strategies, respectively, using a highly effective vaccine. With or without including exogenous boosting impact and/or HZ-related costs and health benefits, the 1D strategy is least costly, but 2-dose strategies are cost-effective considering a willingness-to-pay threshold equivalent to the gross domestic product. The model predicted a modest increase in HZ burden during the first 20-30 years, after which time HZ incidence equilibrates at a lower rate than pre-vaccine. CONCLUSIONS Our findings support adding a second varicella vaccine dose in Turkey, as doing so is highly cost-effective across a wide range of assumptions regarding the burden associated with varicella and HZ disease.
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18
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Jung J, Im JH, Ko YJ, Huh K, Yoon CG, Rhee C, Kim YE, Go DS, Kim A, Jung Y, Radnaabaatar M, Yoon SJ. Complementing conventional infectious disease surveillance with national health insurance claims data in the Republic of Korea. Sci Rep 2019; 9:8750. [PMID: 31217476 PMCID: PMC6584579 DOI: 10.1038/s41598-019-45409-3] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/10/2018] [Accepted: 06/06/2019] [Indexed: 12/19/2022] Open
Abstract
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.
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Affiliation(s)
- Jaehun Jung
- Department of Preventive Medicine, Gachon University College of Medicine, Incheon, Korea
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Jae Hyoung Im
- Department of Infectious Diseases, Inha University School of Medicine, Incheon, Republic of Korea
| | - Young-Jin Ko
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Kyungmin Huh
- Department of Infectious Diseases, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Republic of Korea
| | - Chang-Gyo Yoon
- Preventive Medicine Program, Graduate School of Public Health, Seoul National University, Seoul, Korea
| | - Chulwoo Rhee
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Young-Eun Kim
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Dun-Sol Go
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Arim Kim
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Yunsun Jung
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Munkhzul Radnaabaatar
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea
| | - Seok-Jun Yoon
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Republic of Korea.
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19
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Choi JK, Park SH, Park S, Choi SM, Kim SH, Lee DG, Yoo JH, Choi JH, Kang JH. Trends in varicella and herpes zoster epidemiology before and after the implementation of universal one-dose varicella vaccination over one decade in South Korea, 2003-2015. Hum Vaccin Immunother 2019; 15:2554-2560. [PMID: 31008679 DOI: 10.1080/21645515.2019.1603985] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023] Open
Abstract
Background: In South Korea, the one-dose varicella vaccine was included in the National Immunization Program for children aged 12-15 months in 2005, and the vaccine coverage reached >95%. The impact of varicella vaccination on varicella and herpes zoster (HZ) was investigated, accounting for demographic changes over time.Methods: We calculated the crude and age-sex standardized incidence rates (IRs) and age-specific IRs of varicella and HZ from 2003 to 2015, using the National Health Information Database including approximately 50 million Koreans. The annual incidence rate ratios (IRRs) were calculated using a negative binomial regression analysis, adjusting for age and sex.Results: The crude varicella IR steadily declined by 67%, from 5.70/1000 to 1.87/1000 person years (IRR per year: 0.91; 95% CI 0.89-0.93), but the adjusted IRs showed a significant decline only during 2010-2015 (adjusted IRR per year: 0.90; 95% CI 0.88-0.93). The greatest decline was found in children ≤4 years of age, whereas the IR increased until 2011 and then declined afterward in children aged 5-9 years, who represented the highest incidence age group in 2013-2015. The crude HZ IR increased from 2.67/1000 to 9.80/1000 person years (IRR per year: 1.12; 95% CI 1.10-1.15), and the adjusted IR also followed the same trend. A similar increasing trend was observed before and after universal vaccination.Conclusions: One-dose varicella vaccination was moderately effective in preventing varicella, but this strategy was insufficient to interrupt varicella transmission in children. Furthermore, the HZ incidence dramatically increased over this decade. The current vaccination strategy against varicella-zoster disease should be reconsidered.
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Affiliation(s)
- Jae-Ki Choi
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sun Hee Park
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Sanghyun Park
- Department of Biostatistics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Su-Mi Choi
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Si-Hyun Kim
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Dong-Gun Lee
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jin-Hong Yoo
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jung-Hyun Choi
- Division of Infectious Diseases, Department of Internal Medicine, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
| | - Jin Han Kang
- Vaccine Bio Research Institute, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea.,Department of Pediatrics, College of Medicine, The Catholic University of Korea, Seoul, Republic of Korea
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20
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Lee YH, Choe YJ, Cho SI, Park H, Bang JH, Lee JK. Effects of One-dose Varicella Vaccination on Disease Severity in Children during Outbreaks in Seoul, Korea. J Korean Med Sci 2019; 34:e83. [PMID: 30886550 PMCID: PMC6417997 DOI: 10.3346/jkms.2019.34.e83] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 10/26/2018] [Accepted: 02/22/2019] [Indexed: 11/20/2022] Open
Abstract
BACKGROUND In Korea, the incidence of varicella has increased despite the introduction of a universal one-dose vaccination for children aged 12-15 months in 2005. A previous study demonstrated that the vaccine effectiveness was insufficient to prevent against varicella. We assessed the effect of the varicella vaccination on disease severity. METHODS Epidemiologic investigation of varicella cases in Seoul metropolitan area from 2015 to 2017 were used. Varicella-related symptoms such as rash were determined by the clinical practitioners. Disease severity of patients was assessed by the number of skin lesions and divided into mild (≤ 50) and moderate (51-249) to severe (≥ 250). Unconditional logistic regression analysis was performed and age was controlled. RESULTS Among a total of 1,008 varicella cases reported, 869 cases were breakthrough cases and 139 were unvaccinated cases. The risk for occurrence of moderate-to-severe disease in the breakthrough group was 0.57 times less than that of the unvaccinated group. CONCLUSION These data suggest that national varicella vaccination may have a significant effect on attenuation of disease severity in children.
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Affiliation(s)
- Young Hwa Lee
- Department of Epidemiology, Seoul National University Graduate School of Public Health, Seoul, Korea
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
| | - Young June Choe
- Division of Pediatric Infectious Diseases, The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Sung-Il Cho
- Department of Epidemiology, Seoul National University Graduate School of Public Health, Seoul, Korea
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
| | - HyeKyung Park
- Division of Infectious Disease Surveillance, Center for Control of Infectious Diseases, KCDC, Osong, Korea
| | - Ji Hwan Bang
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
- Division of Infectious Diseases, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Korea
| | - Jong-koo Lee
- Institute of Infectious Disease, Seoul National University College of Medicine, Seoul, Korea
- Department of Family Medicine, Seoul National University College of Medicine, Seoul, Korea
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21
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Jung J, Ko YJ, Kim YE, Huh K, Park BJ, Yoon SJ. Epidemiological Impact of the Korean National Immunization Program on Varicella Incidence. J Korean Med Sci 2019; 34:e53. [PMID: 30804728 PMCID: PMC6384433 DOI: 10.3346/jkms.2019.34.e53] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 08/13/2018] [Accepted: 12/18/2018] [Indexed: 11/20/2022] Open
Abstract
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.
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Affiliation(s)
- Jaehun Jung
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
- Department of Preventive Medicine, Gachon University College of Medicine, Incheon, Korea
| | - Young-Jin Ko
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Young-Eun Kim
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
| | - Kyungmin Huh
- Division of Infectious Disease, Department of Medicine, Samsung Medical Center, Sungkyunkwan University School of Medicine, Seoul, Korea
| | - Byung-Joo Park
- Department of Preventive Medicine, Seoul National University College of Medicine, Seoul, Korea
| | - Seok-Jun Yoon
- Department of Preventive Medicine, Korea University College of Medicine, Seoul, Korea
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22
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Lee YH, Choe YJ, Cho SI, Bang JH, Oh MD, Lee JK. Increasing varicella incidence rates among children in the Republic of Korea: an age-period-cohort analysis. Epidemiol Infect 2019; 147:e245. [PMID: 31364576 PMCID: PMC6805734 DOI: 10.1017/s0950268819001389] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/20/2018] [Revised: 05/18/2019] [Accepted: 05/31/2019] [Indexed: 11/06/2022] Open
Abstract
In the Republic of Korea, despite the introduction of one-dose universal varicella vaccination in 2005 and achieving a high coverage rate of 98.9% in 2012, the incidence rate has been increased sevenfold. This study aimed to investigate time trends of varicella incidence rate, assessing the age, period and birth cohort effects. We used national data on the annual number of reported cases from 2006 to 2017. A log-linear Poisson regression model was used to estimate age-period-cohort effects on varicella incidence rate. From 2006 to 2017, the incidence of varicella increased from 22.5 cases to more than 154.8 cases per 100 000. Peak incidence has shifted from 4 to 6 years old. The estimated period and cohort effects showed significant upward patterns, with a linear increasing trend by net drift. There has been an increase in the incidence among the Korean population regarding period and cohort despite the universal vaccination of varicella vaccine. Our data suggest the need for additional studies to address the current gap in herd immunity.
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Affiliation(s)
- Young Hwa Lee
- Department of Epidemiology, Seoul National University School of Public Health, Seoul, Republic of Korea
| | - Young June Choe
- Division of Pediatric Infectious Diseases, The Warren Alpert Medical School of Brown University, Providence, RI, USA
| | - Sung-Il Cho
- Department of Epidemiology, Seoul National University School of Public Health, Seoul, Republic of Korea
| | - Ji Hwan Bang
- Division of Infectious Diseases, Seoul Metropolitan Government-Seoul National University Boramae Medical Center, Seoul, Republic of Korea
| | - Myoung-don Oh
- Department of Internal Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
| | - Jong-Koo Lee
- Department of Family Medicine, Seoul National University College of Medicine, Seoul, Republic of Korea
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23
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Varela FH, Pinto LA, Scotta MC. Global impact of varicella vaccination programs. Hum Vaccin Immunother 2018; 15:645-657. [PMID: 30427766 PMCID: PMC6605725 DOI: 10.1080/21645515.2018.1546525] [Citation(s) in RCA: 85] [Impact Index Per Article: 14.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2018] [Revised: 10/12/2018] [Accepted: 10/29/2018] [Indexed: 12/19/2022] Open
Abstract
Although varicella is usually a mild and self-limited disease, complications can occur. In 1998, the World Health Organization recommended varicella vaccination for countries where the disease has a significant public health burden. Nonetheless, concerns about a shift in the disease to older groups, an increase in herpes zoster in the elderly and cost-effectiveness led many countries to postpone universal varicella vaccine introduction. In this review, we summarize the accumulating evidence, available mostly from high and middle-income countries supporting a high impact of universal vaccination in reductions of the incidence of the disease and hospitalizations and its cost-effectiveness. We have also observed the effect of herd immunity and noted that there is no definitive and consistent association between vaccination and the increase in herpes zoster incidence in the elderly.
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Affiliation(s)
- Fernanda Hammes Varela
- Centro Infant, Department of Pediatrics, School of Medicine, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul state, Brazil
| | - Leonardo Araújo Pinto
- Centro Infant, Department of Pediatrics, School of Medicine, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul state, Brazil
| | - Marcelo Comerlato Scotta
- Centro Infant, Department of Pediatrics, School of Medicine, Pontifícia Universidade Católica do Rio Grande do Sul (PUCRS), Porto Alegre, Rio Grande do Sul state, Brazil
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24
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Kim J, Kim JE, Bae JM. Incidence of varicella in children in Jeju-do, Korea, 2005-2016: age-period-cohort analysis. Epidemiol Health 2018; 40:e2018054. [PMID: 30428643 PMCID: PMC6302224 DOI: 10.4178/epih.e2018054] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2018] [Accepted: 11/08/2018] [Indexed: 11/09/2022] Open
Abstract
OBJECTIVES Although the nationwide inoculation rate of varicella vaccine was approximately 95% in Korean children recently, the number of notified varicella cases is unexpectedly continuously increasing till now. To suggest some hypotheses regarding this discrepancy, an age-period-cohort (APC) analysis as a descriptive epidemiology study was conducted for children residing in Jeju-do, Korea. METHODS The raw data were obtained from the nationwide database for insurance claim of healthcare fee provided by the National Health Insurance Service, Korea. The selection criteria were children aged 2-13 years who visited any healthcare center due to varicella from 2005 to 2016 while residing in Jeju-do. After calculating the birth cohort-specific crude incidence rates by age and year, the intrinsic estimator method was used to perform the APC analysis. RESULTS As the annual crude incidence rates decreased with increasing age between 2005 and 2016, the age and period effects also decreased. The intrinsic estimator coefficients suggesting the cohort effect shifted from positive to negative in 2011, the starting year of free varicella vaccine program in Jeju-do. CONCLUSIONS The results suggested that inoculated varicella vaccines have preventive effects. However, further studies to evaluate waning immunity would be needed.
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Affiliation(s)
- Jinhee Kim
- Jeju Center for Infection Control, Jeju, Korea
| | - Ji-Eun Kim
- Jeju Center for Infection Control, Jeju, Korea
| | - Jong-Myon Bae
- Department of Preventive Medicine, Jeju National University School of Medicine, Jeju, Korea
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25
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Oh HS, Bae JM. Vaccination history in elementary school children enrolled in the varicella epidemic investigations held in Jeju-si, Korea in the first half of 2017. Epidemiol Health 2017; 39:e2017053. [PMID: 29278902 PMCID: PMC5790978 DOI: 10.4178/epih.e2017053] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2017] [Accepted: 11/13/2017] [Indexed: 11/19/2022] Open
Abstract
OBJECTIVES The reported incidence rate of varicella infection in Jeju-do is higher compared with the national average. This study aimed to examine varicella vaccination history and evaluate clinical manifestation of varicella cases in Jeju-do. METHODS Based on the guideline suggested by the Korea Centers for Disease Control and Prevention (KCDC), two epidemic investigations for varicella infection were conducted in the first half of 2017. The history of varicella vaccination was confirmed using the Integrated Control System for Diseases and Health operated by the KCDC. RESULTS Out of a total of 60 elementary school children as the study subjects, all had been previously vaccinated against varicella. Twenty cases (33%) showed mild clinical manifestations and no complications. CONCLUSIONS As the government of Jeju-do has supplied a single-labeled vaccine since 2011, there is a need to evaluate the type of vaccination failure such as primary or secondary.
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Affiliation(s)
- Hyun-Suk Oh
- Jeju Heathcare Center of Jeju-si, Jeju, Korea
| | - Jong-Myon Bae
- Department of Preventive Medicine, Jeju National University Scool of Medicine, Jeju, Korea
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26
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Daulagala SWPL, Noordeen F, Fara MMF, Rathnayake C, Gunawardana K. Exposure rate of VZV among women attending antenatal care clinic in Sri Lanka - a cross sectional study. BMC Infect Dis 2017; 17:625. [PMID: 28915849 PMCID: PMC5602960 DOI: 10.1186/s12879-017-2725-x] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2017] [Accepted: 09/11/2017] [Indexed: 02/01/2023] Open
Abstract
Background Varicella or chickenpox was not a notifiable disease until 2005 in Sri Lanka and only a few studies have been conducted on the epidemiology of VZV infection in the country. The antiVZV IgG sero-prevalence among antenatal women is extremely limited and thus a selected group of antenatal clinic attendees were chosen to determine the exposure rate to VZV infection. Methods Women attending the antenatal clinic at Teaching Hospital, Peradeniya, Sri Lanka were selected for the study and 3 mL of venous blood was collected from 181 participants and the demographic data was obtained through a pretested questionnaire. Sera of the women were then tested for the presence of antiVZV IgG using ELISA (HUMAN Diagnostics, Germany). Data was analysed using the SPSS statistical software for Windows, Version 12.0. Results Of the 181 antenatal women who took part in the study, 141 were positive for antiVZV IgG giving a sero-prevalence of 77.9% for the past exposure to VZV. Of the 141 antiVZV IgG positive women, 43.3% (n = 61) were from urban, 41.8% (n = 59) were from rural and 14.9% (n = 21) were from estate populations (an ethnic population living in small settlements in the tea estates whose ancestors were brought from India during the British colonial period to work in the tea plantations in Sri Lanka). Out of the 88 antenatal women with a positive history for varicella, 85 (96.6%) were positive for anti-VZV IgG. The highest number of antiVZV IgG positivity was seen in the 31–35 age group, which was 85.0% of the total number of antenatal women included in that category. An increase in the antiVZV IgG sero-prevalence with increasing age was also noted in the study sample. Conclusion Exposure rate of VZV infection as confirmed by antiVZV IgG in the present study sample of antenatal women was 77.9%. Age specific, population based future sero-prevalence studies should be conducted in Sri Lanka to understand the anti-VZV IgG status in the country.
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Affiliation(s)
| | - Faseeha Noordeen
- Department of Microbiology, Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka.
| | | | - Chathura Rathnayake
- Department of Gynecology and Obstetrics, Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka
| | - Kapila Gunawardana
- Department of Gynecology and Obstetrics, Faculty of Medicine, University of Peradeniya, Peradeniya, Sri Lanka
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Wutzler P, Bonanni P, Burgess M, Gershon A, Sáfadi MA, Casabona G. Varicella vaccination - the global experience. Expert Rev Vaccines 2017. [PMID: 28644696 DOI: 10.1080/14760584.2017.1343669] [Citation(s) in RCA: 115] [Impact Index Per Article: 16.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/30/2023]
Abstract
INTRODUCTION Varicella, although a frequently benign childhood disease, nevertheless represents a considerable health burden. WHO recommends including varicella vaccines in universal routine vaccination programs, and maintaining coverage >80%. Many countries have successfully introduced varicella vaccination and have benefited from lower disease burden, but many others have not adopted the vaccine. Reasons include cost commitment for a 'mild childhood disease' or concerns that vaccination will shift varicella to older age groups or increase herpes zoster incidence. Areas covered: This literature review summarizes the effectiveness and epidemiological impact of varicella immunization programs. Expert commentary: Varicella vaccines are immunogenic with acceptable safety profiles. One and two dose schedules are highly effective against varicella and large reductions in disease incidence, particularly moderate-severe disease, have been widely reported. There is currently no evidence to suggest that the introduction of varicella vaccination results in a shift of varicella disease burden to older age groups. Although epidemiological studies have shown an increased incidence of herpes zoster since the vaccines were launched, there are many other contributing factors, and indeed, this secular trend was evident before their introduction. In conclusion, varicella vaccination easily fits into existing immunization programs and significantly reduces the often underestimated burden of varicella.
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Affiliation(s)
- Peter Wutzler
- a Institute of Virology and Antiviral Therapy , Friedrich Schiller University , Jena , Germany
| | - Paolo Bonanni
- b Department of Health Sciences , University of Florence , Florence , Italy
| | - Margaret Burgess
- c The Discipline of Paediatrics and Adolescent Health , University of Sydney , Sydney , Australia
| | - Anne Gershon
- d Division of Infectious Disease , Columbia University , New York , NY , USA
| | - Marco Aurélio Sáfadi
- e Department of Pediatrics , Santa Casa de Sao Paulo School of Medical Sciences , Sao Paulo , Brazil
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