Abstract: | Quadruple vaccines (DTP-P), prepared by mixing crude adsorbed Salk poliomyelitis vaccines, heat-killed pertussis vaccines and adsorbed purified diphtheria and tetanus toxoids were found to be toxic for mice. However, by using purified poliomyelitis and heat-killed formalinized pertussis components, vaccines were prepared that were non-toxic. The pertussis component of these vaccines retained potency over extended periods of storage. Stable, potent DTP-P vaccines offer an excellent alternative to DTP and live poliomyelitis vaccine in the basic immunization of infants and children. |