Development of Efficient Prophylactic Vaccines and Theracines for Newborns and Infants

Abstract

Vaccines represent one of the most impressive successes of experimental medicine, allowing for the eradication of a causative infectious agent and extinction of diseases such as variola, which is caused by smallpox. The vaccine against variola was discovered by Jenner 200 yr ago based on the observation that the injection of a boy with cowpox was protected against two successive inoculations with the deadly smallpox virus. The global vaccination with vaccinia led to the almost total eradication of the smallpox virus. Classical vaccines developed later through discoveries pioneered by Pasteur and Ramon led to definition of a golden rule of vaccine preparation that consists of the principle of inactivation of the pathogenicity of a microbe or bacterial toxin without altering their immunogenicity—namely, the ability to induce a protective immune response. Fervent advancement in vaccinology established that an ideal vaccine should be endowed with the following properties: (a) The microbe used to prepare the vaccine should exhibit a constant antigen specificity without being the subject of genetic variation; (b) it should induce protective immunity; (c) the protection should be life-long, because it should induce immune memory, allowing a primed host to react rapidly to an infectious agent; and (d) it should be devoid of side effects.