Impact of the sequential poliovirus immunization schedule: A demonstrationproject

Objective: Researchers for this pi-eject evaluated compliance with the sequ ential poliovirus immunization schedule that uses inactivated poliovirus va ccine (IPV) for the first 2 doses of the polio immunization series, and ass essed immunization coverage rates before and after implementation of this s chedule at 6 public health clinics serving I county in Georgia. Design: Immunization histories for 3 birth cohorts of infants were compared : (1) the baseline cohort, born January 1 through June 30, 1995; (2) the ev aluation cohort, born January 1 through June 30, 1997, after implementation of the schedule change; and (3) the dose-3 cohort, born August 1 through N ovember 30, 1996 (i.e., old enough to be eligible for a third dose of polio virus vaccine following implementation of the sequential schedule). Results: Following implementation of the new poliovirus immunization recomm endations, 94% (534 of 567) of infants who received their first dose of pol iovirus vaccine by age 3 months received IPV. Among these infants, 99.6% (5 32 of 534) were also up to date (UTD) for first doses of diphtheria and tet anus toxoids and acellular pertussis vaccine (DTP1/DTaP1), 99.6% (532 of 53 4) were UTD for first doses of hemophilus influenza type b (Hib I), and 98. 6% (527 of 534) had received at least one dose of Hepatitis B. Among infant s visiting the clinics for their first or second dose of poliovirus vaccine , DTaP/DTP, and/or Hib, 76% received 3 or 4 simultaneous injections. In the dose-3 cohort, 78% (145 of 185) of infants who received a third dose of po liovirus vaccine had received 2 doses of IPV and I dose of oral poliovirus vaccine. Conclusions: Compliance with the recommended use of IPV for the first 2 pol iovirus immunization doses as part of the sequential schedule was very high ill this low-income and ethnically diverse population. Furthermore, the ne ed for additional injections did not impede the delivery of recommended chi ldhood immunizations. (C) 2000 American Journal of Preventive Medicine.