title: Seroprevalence of measles among children affected by national measles elimination program in Korea, 2010.
abstract: BACKGROUND
  Following the implementation of national measles elimination plan in Korea, the elimination was declared in 2006. In order to sustain the elimination, high population immunity should be continuously monitored. To evaluate the current age-related susceptibility within the Korean population, we conducted the seroprevalence in children and adolescents who were affected by the national measles elimination plan.
  
  
  METHODS
  We used residual serum specimens to measure measles specific IgG and geometric mean titer (GMT) in birth cohorts 2007-2008 and 1997-2003. Among birth cohorts, 2007-2008 cohorts were grouped to evaluate the timeliness of first dose of MMR, 1994-2003 cohorts were grouped to evaluate the effect of keep-up MMR2 campaign, and 1992-1993 cohorts were grouped to evaluate the effect of catch-up campaign in 2001.
  
  
  RESULTS
  Overall, measles seropositivity rate was 86%. The highest seroprevalence of measles IgG was in birth cohorts 2007-2008. Measles seropositivity declined continuously in age groups. The birth cohorts 1994-1996 showed significantly lower levels of seropositivity and GMT than did the other birth cohorts.
  
  
  CONCLUSIONS
  Despite efforts to eliminate measles for the past 10 years in Korea, our study revealed specific birth cohorts remaining at risk for transmission. The adolescents born during 1994-1996 had the lowest measles seropositivity levels, and might represent a 'pocket' that has potential at increased risk for measles transmission. Further discussion for follow-up immunization should be placed for consideration in the near future.
authors.affiliation: Division of Vaccine Preventable Disease Control and National Immunization Program, Korea Centers for Disease Control and Prevention, Osong, Republic of Korea.
authors.forename: Eun Seong
authors.initials: ES
authors.lastname: Kim
authors.forename: Young June
authors.initials: YJ
authors.lastname: Choe
authors.forename: Heeyeon
authors.initials: H
authors.lastname: Cho
authors.forename: You-Jin
authors.initials: YJ
authors.lastname: Kim
authors.forename: Hee Sook
authors.initials: HS
authors.lastname: Yoon
authors.forename: Jeong-Sun
authors.initials: JS
authors.lastname: Yang
authors.forename: Kisoon
authors.initials: K
authors.lastname: Kim
authors.forename: Geun-Ryang
authors.initials: GR
authors.lastname: Bae
authors.forename: Duk-hyoung
authors.initials: DH
authors.lastname: Lee
mesh_terms: D000293:Adolescent; D000914:Antibodies, Viral / Q000097:blood; D002648:Child; D002675:Child, Preschool; D015331:Cohort Studies; D060740:Disease Eradication; D005260:Female; D006801:Humans; D007074:Immunoglobulin G / Q000097:blood; D008297:Male; D008457:Measles / Q000453:epidemiology / Q000517:prevention & control* / Q000635:transmission; D008458:Measles Vaccine / Q000008:administration & dosage / Q000276:immunology*; D056910:Republic of Korea / Q000453:epidemiology; D018570:Risk Assessment; D016036:Seroepidemiologic Studies
chemical_list: D000914:Antibodies, Viral; D007074:Immunoglobulin G; D008458:Measles Vaccine