title: Impact of multiple injections on immunization rates among vulnerable children.
abstract: BACKGROUND
  In 1997, the Advisory Committee on Immunization Practices (ACIP) recommended a switch from oral polio vaccine (OPV) to inactivated polio vaccine (IPV) for the first two infant doses. The ACIP also recommended use of diphtheria, tetanus, and acellular pertussis vaccine (DTaP) for infants. These recommendations resulted in two additional injections at the 2- and 4-month immunization visits. This study evaluates the implementation of new IPV and DTaP immunization recommendations and their impact on immunization coverage levels.
  
  
  METHODS
  Immunization coverage was assessed in public clinics in three urban areas before and after the recommendations. One pre- and three post-recommendation cohorts were followed to 12 months of age.
  
  
  RESULTS
  Almost all (> or = 88%) infants in the pre-recommendation cohort received OPV, DTP, and only one or two injections. Almost all (> or = 78%) infants in the post-recommendation cohorts received IPV, DTaP, and three or four injections. The percentage of infants in the post-recommendation cohorts up-to-date for immunizations at 12 months of age was slightly higher than those in the pre-recommendation cohort.
  
  
  CONCLUSIONS
  Providers rapidly switched from OPV and DTP to IPV and DTaP. Coverage at 12 months of age was higher among IPV/DTaP recipients than among OPV/DTP recipients. Provider and parent acceptance of four injections at a visit was high. The recent pneumococcal conjugate vaccine recommendations potentially add a fifth injection at 2 and 4 months of age. Acceptance or rejection of five injections by providers and parents needs early assessment.
authors.affiliation: Immunization Services Division, National Immunization Program, Centers for Disease Control and Prevention, Atlanta, Georgia 30333, USA. mkolasa.cdc.gov
authors.forename: M S
authors.initials: MS
authors.lastname: Kolasa
authors.forename: T J
authors.initials: TJ
authors.lastname: Petersen
authors.forename: E W
authors.initials: EW
authors.lastname: Brink
authors.forename: I D
authors.initials: ID
authors.lastname: Bulim
authors.forename: J M
authors.initials: JM
authors.lastname: Stevenson
authors.forename: L E
authors.initials: LE
authors.lastname: Rodewald
mesh_terms: D002662:Child Health Services / Q000706:statistics & numerical data*; D015331:Cohort Studies; D015721:Diphtheria-Tetanus-Pertussis Vaccine / Q000008:administration & dosage*; D006801:Humans; D017589:Immunization Programs / Q000458:organization & administration* / Q000706:statistics & numerical data; D007115:Immunization Schedule; D007223:Infant; D011054:Poliovirus Vaccine, Inactivated / Q000008:administration & dosage*; D014481:United States; D014505:Urban Population
chemical_list: D015721:Diphtheria-Tetanus-Pertussis Vaccine; D011054:Poliovirus Vaccine, Inactivated