Factors affecting responses to immunization

Geoffrey Edsall once stated "...at its best, immunization is the cheapest and most practical means of controlling infectious disease...". While immunization against some diseases has been highly successful, the efficacy of some vaccines is far from adequate. Basic immunological research has identified many factors which control the development and operation of the immune system of vertebrate animals; application of this information to the development and practical use of vaccines for humans may eventually benefit this general approach to the control of infectious disease.