title: Varicella and varicella vaccination in South Korea.
abstract: With continuing occurrence of varicella despite increasing vaccine coverage for the past 20 years, a case-based study, a case-control study, and an immunogenicity and safety study were conducted to address the impact of varicella vaccination in South Korea. Varicella patients under the age of 16 years were enrolled for the case-based study. For the case-control study, varicella patients between 12 months and 15 years of age were enrolled with one control matched for each patient. For the immunogenicity and safety study, otherwise healthy children from 12 to 24 months old were immunized with Suduvax (Green Cross, South Korea). Fluorescent antibody to membrane antigen (FAMA) varicella-zoster virus (VZV) antibody was measured before and 6 weeks after immunization. In the case-based study, the median age of the patients was 4 years. Among 152 patients between 1 and 15 years of age, 139 children received varicella vaccine and all had breakthrough infections. Clinical courses were not ameliorated in vaccinated patients, but more vaccinated patients received outpatient rather than inpatient care. In the case-control study, the adjusted overall effectiveness of varicella vaccination was 54%. In the immunogenicity and safety study, the seroconversion rate and geometric mean titer for FAMA antibody were 76.67% and 5.31. Even with increasing varicella vaccine uptake, we illustrate no upward age shift in the peak incidence, a high proportion of breakthrough disease, almost no amelioration in disease presentation by vaccination, and insufficient immunogenicity of domestic varicella vaccine. There is need to improve the varicella vaccine used in South Korea.
authors.affiliation: Department of Pediatrics, Hanyang University Medical Center, Seoul, Republic of Korea.
authors.forename: Sung Hee
authors.initials: SH
authors.lastname: Oh
authors.forename: Eun Hwa
authors.initials: EH
authors.lastname: Choi
authors.forename: Seon Hee
authors.initials: SH
authors.lastname: Shin
authors.forename: Yun-Kyung
authors.initials: YK
authors.lastname: Kim
authors.forename: Jin Keun
authors.initials: JK
authors.lastname: Chang
authors.forename: Kyong Min
authors.initials: KM
authors.lastname: Choi
authors.forename: Jae Kyun
authors.initials: JK
authors.lastname: Hur
authors.forename: Kyung-Hyo
authors.initials: KH
authors.lastname: Kim
authors.forename: Jae Youn
authors.initials: JY
authors.lastname: Kim
authors.forename: Eun Hee
authors.initials: EH
authors.lastname: Chung
authors.forename: Soo Young
authors.initials: SY
authors.lastname: Lee
authors.forename: Su Eun
authors.initials: SE
authors.lastname: Park
authors.forename: Sungho
authors.initials: S
authors.lastname: Cha
authors.forename: Kwang-Nam
authors.initials: KN
authors.lastname: Kim
authors.forename: Sang Hyuk
authors.initials: SH
authors.lastname: Ma
authors.forename: Byung Wook
authors.initials: BW
authors.lastname: Eun
authors.forename: Nam Hee
authors.initials: NH
authors.lastname: Kim
authors.forename: Dae Sun
authors.initials: DS
authors.lastname: Jo
authors.forename: Bo Youl
authors.initials: BY
authors.lastname: Choi
authors.forename: Shin Ah
authors.initials: SA
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood; D016022:Case-Control Studies; D002644:Chickenpox / Q000453:epidemiology* / Q000473:pathology / Q000517:prevention & control*; D019433:Chickenpox Vaccine / Q000008:administration & dosage* / Q000009:adverse effects / Q000276:immunology*; D002648:Child; D002675:Child, Preschool; D005260:Female; D006801:Humans; D007223:Infant; D008297:Male; D056910:Republic of Korea / Q000453:epidemiology; D014611:Vaccination / Q000009:adverse effects / Q000706:statistics & numerical data
chemical_list: D000914:Antibodies, Viral; D019433:Chickenpox Vaccine