title: Persistence of mumps antibodies after 2 doses of measles-mumps-rubella vaccine.
abstract: BACKGROUND
  Since 1990, most US schoolchildren have received a second dose of measles-mumps-rubella vaccine (MMR2) at kindergarten entry. The objective of the present study was to evaluate the short- and long-term mumps immunogenicity of MMR2.
  
  
  METHODS
  At enrollment in 1994-1995, children (n=308) in a rural Wisconsin health maintenance organization received MMR2 at age 4-6 years. A comparison group of older children (n=308) was vaccinated at age 9-11 years. Serum samples were collected over 12 years. Mumps antibody levels were evaluated by plaque-reduction neutralization (lowest detectable titer, 10).
  
  
  RESULTS
  Before MMR2, the geometric mean titer (GMT) for the younger group was 33; no subject was seronegative, but 16% had the lowest detectable titer. In response to MMR2, the GMT tripled to 97, and the proportion with low titers diminished to 3%. Four-fold boosts occurred among 54%, but only 3% were positive for immunoglobulin M. Twelve years after MMR2, the GMT declined to 46, the proportion with titers<or=10 was not significantly different from the pre-MMR2 proportion, and 5% were seronegative. The older group showed similar patterns, and at age 17 years both groups had comparable antibody levels.
  
  
  CONCLUSIONS
  The mumps antibody response to MMR2 was vigorous, but over a 12-year period titers declined to levels similar to pre-MMR2 titers. No advantage was apparent in delaying MMR2 from kindergarten to middle school.
authors.affiliation: Division of Viral Diseases, National Center for Immunization and Respiratory Diseases, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. clebaron@cdc.gov
authors.forename: Charles W
authors.initials: CW
authors.lastname: LeBaron
authors.forename: Bagher
authors.initials: B
authors.lastname: Forghani
authors.forename: Carol
authors.initials: C
authors.lastname: Beck
authors.forename: Cedric
authors.initials: C
authors.lastname: Brown
authors.forename: Daoling
authors.initials: D
authors.lastname: Bi
authors.forename: Cynthia
authors.initials: C
authors.lastname: Cossen
authors.forename: Bradley J
authors.initials: BJ
authors.lastname: Sullivan
mesh_terms: D000914:Antibodies, Viral / Q000097:blood*; D002648:Child; D002675:Child, Preschool; D004306:Dose-Response Relationship, Immunologic; D005260:Female; D006801:Humans; D007117:Immunization, Secondary; D008297:Male; D022542:Measles-Mumps-Rubella Vaccine / Q000276:immunology*; D009107:Mumps / Q000517:prevention & control; D009109:Mumps virus / Q000276:immunology*; D013997:Time Factors; D014922:Wisconsin
chemical_list: D000914:Antibodies, Viral; D022542:Measles-Mumps-Rubella Vaccine