Interchangeability of vaccines.

Abstract

The delivery of childhood immunizations can be complex, often requiring numerous injections over months or years to complete the recommended schedule. The ability to interchange similar vaccines from different manufacturers during a vaccination series is important because the product administered previously may be unknown or no longer available. The current vaccine literature was reviewed to identify available data and determine the consensus on the interchangeability of current vaccines. In the instance of diphtheria-tetanus toxoids-acellular pertussis (DTPa) vaccine, no serologic markers of protective efficacy against Bordetella pertussis exist; therefore it is difficult to evaluate interchangeability of available products. Consequently the ACIP, AAP and AAFP have recommended that the same DTPa product be used for the first three doses of the immunization series. However, if the previously administered product is unknown or not readily available, any licensed DTPa product may be used. More recent data suggest that at least some of the DTPa products have similar immunogenicity and appear to be interchangeable. For other families of vaccines, such as those designed to prevent infection with hepatitis B virus, poliovirus and Haemophilus influenzae type b, there is good evidence attesting to sustained immunogenicity when products from different manufacturers are used to complete a series. The use of approved combination vaccine products whenever possible is advocated by the ACIP, AAP and AAFP because such products decrease the number of injections needed to complete the recommended immunizations and may reduce health care costs, improve program performance and aid in documentation of administered vaccines.