ABSTRACT
Vaccines are the most effective means of prevention of diseases. Eradication of small pox worldwide attests to the power of this preventive strategy. The rarity of infectious diseases such as diphtheria, tetanus, pertussis, mumps, and measles in the Western world is largely due to successful immunizations. Development of effective vaccines is seen as the hope for prevention of other infectious diseases such as malaria, AIDS, and hepatitis B and C infections.
