Technology for Prophylactic Immunization [and Discussion]

The World Health Organization's expanded programme on immunization demands the use of stabilized vaccines, especially in countries in which the ambient temperatures are high. Although much is known about the stability of DPT, BCG, measles and poliomyelitis vaccines when stored in the domestic refrigerator at between 2 and 8 degrees C, little is known of their stability when exposed to higher temperatures. The conditions of storage and transport of vaccine in the developing countries are presented and the types of refrigerators forming the cold chain in these countries are outlined. Finally a simplified immunization schedule suitable for the Third World is presented.