Skip Navigation
Skip to contents

Epidemiol Health : Epidemiology and Health

OPEN ACCESS
SEARCH
Search
Advanced Search
mobile menu button

Search

Page Path
HOME > Search
2 "Immunization programs"
Filter
Filter
Article category
Keywords
More +
Publication year
Authors
More +
Funded articles
COVID-19: Original Article
Risk of new-onset seizures following immunization against COVID-19: a self-controlled case-series study
Hwa Yeon Ko, Dongwon Yoon, Ju Hwan Kim, Han Eol Jeong, Seung Bong Hong, Won-Chul Shin, Ju-Young Shin, on behalf of the CoVaSC Investigators
Epidemiol Health. 2025;47:e2025024.   Published online May 2, 2025
DOI: https://doi.org/10.4178/epih.e2025024
  • 10,808 View
  • 124 Download
AbstractAbstract AbstractSummary PDFSupplementary Material
Abstract
OBJECTIVES
Despite emerging reports of new-onset seizures (NOS) following coronavirus disease 2019 (COVID-19) vaccination, safety evidence regarding the risk of NOS after vaccination remains limited. We aimed to investigate the potential association between NOS and COVID-19 vaccination.
METHODS
We conducted a self-controlled case series study utilizing a nationwide database linking the COVID-19 vaccination registry and the National Health Information Database (from February 2021 to October 2022). We identified adults (≥18 years) who received COVID-19 vaccination (BNT162b2, ChAdOx1 nCoV-19, mRNA-1273, NVX-CoV2373, or Ad26.COV2.S) and had a diagnosis of NOS accompanied by prescriptions of anti-seizure drugs. The observation period was defined as 240 days following vaccination. We evaluated the risk of NOS during a risk window of 28 days after vaccination compared to the control window (the remaining observation period excluding the risk window). Incidence rate ratios (IRRs) with 95% confidence intervals (CIs) were estimated using a conditional Poisson regression model.
RESULTS
Among 42,155,198 COVID-19 vaccine recipients, we identified 1,849 and 4,217 patients with NOS in the risk and control windows, respectively. There was no increased risk of NOS within the 28-day period following vaccination (IRR, 0.99; 95% CI, 0.94 to 1.05). Although results from subgroup analyses by vaccine type were largely consistent with the main findings (IRR, 0.95; 95% CI, 0.88 to 1.03 for BNT162b2; IRR, 0.95; 95% CI, 0.77 to 1.16 for ChAdOx1 nCoV-19; IRR, 1.58; 95% CI, 0.52 to 4.83 for Ad26.COV2.S), a marginally elevated risk was observed for mRNA-1273 (IRR, 1.21; 95% CI, 1.04 to 1.42).
CONCLUSIONS
There was no evidence of an increased risk of NOS following COVID-19 vaccination. These findings can be used as safety evidence in clinical decision-making and to bolster public confidence in COVID-19 vaccines.
Summary
Korean summary
· 질병관리청 코로나19백신 접종 등록자료와 국민건강보험공단의 청구 데이터베이스 연계 자료원을 활용하여 코로나19백신 접종과 경련/발작 발생 간의 관련성에 대한 안전성 평가를 수행함. · 자기-대조환자군 연구설계를 적용하여 4,215만 명 이상의 코로나19백신 접종자를 대상으로 분석한 결과, 대부분의 백신 종류에서 접종 후 28일 이내에 경련/발작 발생 위험이 증가하지 않았으며, mRNA-1273 백신에서만 위험이 다소 증가한 것으로 나타남. · 전반적으로, 본 연구는 코로나19백신 접종 후 경련/발작 발생 위험이 증가하지 않음을 보여주었으며, 이는 임상적 의사결정과 백신 안전성에 대한 신뢰를 높이는 근거로 활용될 수 있음.
Key Message
· A nationwide self-controlled case series study investigated whether COVID-19 vaccination increases the risk of new-onset seizures (NOS) in adults by analyzing over 42 million vaccine recipients. · The results showed no increased risk of NOS within 28 days after vaccination for most vaccine types, with the exception of a marginally elevated risk for the mRNA-1273 vaccine. · Overall, the study found no evidence of increased NOS risk following COVID-19 vaccination, supporting the safety of these vaccines for clinical decision-making.
Original Article
Incidence of varicella in children in Jeju-do, Korea, 2005-2016: age-period-cohort analysis
Jinhee Kim, Ji-Eun Kim, Jong-Myon Bae
Epidemiol Health. 2018;40:e2018054.   Published online November 8, 2018
DOI: https://doi.org/10.4178/epih.e2018054
  • 26,892 View
  • 224 Download
  • 2 Web of Science
  • 3 Crossref
AbstractAbstract AbstractSummary PDFSupplementary Material
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.
Summary
Korean summary
2011년 이후 생후 12-15개월 유아에게 수두백신 무상접종을 시행해 오고 있는 제주도에 있어서, 수두발생 신고건수가 증가하는 괴리 현상에 있어, 국민건강보험공단의 수진자료를 확보하여 연령-기간-코호트 (age-period-cohort, APC) 분석을 시행하였다. 그 결과 연령이 증가하고 연도가 최근으로 올수록 수두 발생에 대한 연령과 기간효과는 점점 감소하는 반면, 수두백신 무상접종이 시작된 2011년을 전후해서 코호트 효과는 양에서 음으로 전환하였다. 따라서 현재 접종하고 있는 수두 백신은 수두발생을 예방하는 효과가 있으며, 돌발수두 발생은 이차백신 실패로 볼 수 있다.

Citations

Citations to this article as recorded by  
  • The comparison of seroconversion rates among different varicella vaccines administered Turkish children; MAV/06 and vOka
    Zuhal Umit, Zumrut Sahbudak Bal, Aysin Zeytinoglu, Tansu Gulbahar Aydogan, Ozlem Bag, Gizem Guner Ozenen, Ferda Ozkinay, Zafer Kurugol
    Human Vaccines & Immunotherapeutics.2021; 17(11): 4190.     CrossRef
  • Recent increase in pertussis incidence in Korea: an age-period-cohort analysis
    Chanhee Kim, Seonju Yi, Sung-il Cho
    Epidemiology and Health.2021; 43: e2021053.     CrossRef
  • Incidence of Scarlet Fever in Children in Jeju Province, Korea, 2002-2016: An Age-period-cohort Analysis
    Jinhee Kim, Ji-Eun Kim, Jong-Myon Bae
    Journal of Preventive Medicine and Public Health.2019; 52(3): 188.     CrossRef
Epidemiol Health : Epidemiology and Health
© Korean Society of Epidemiology.
TOP