title: Hypothesis: how licensed vaccines confer protective immunity.
abstract: By examining experience with evaluation of licensed vaccines we theorize that a critical level of serum IgG confers protection against infectious diseases by killing or inactivating the inoculum. We found that efficacy is reliably predicted by measurement of serum antibodies elicited by vaccines, that serum IgG antibodies alone account for the protection conferred by passive immunization, that vaccine-induced "herd" immunity is best explained by inactivation of the inoculum on epithelial surfaces by serum antibodies and that serum antibodies induced by active immunization will neither treat disease symptoms nor eliminate the pathogen. If valid, this theory should facilitate research because knowledge of the pathogenesis of the disease symptoms may not be essential for vaccine development.
authors.affiliation: Laboratory of Developmental and Molecular Immunity National Institute of Child Health and Human Development, NIH, Bethesda, Maryland 20892, USA.
authors.forename: J B
authors.initials: JB
authors.lastname: Robbins
authors.forename: R
authors.initials: R
authors.lastname: Schneerson
authors.forename: S C
authors.initials: SC
authors.lastname: Szu
mesh_terms: D000818:Animals; D000917:Antibody Formation; D001428:Bacterial Vaccines / Q000592:standards; D006801:Humans; D007116:Immunization, Passive / Q000592:standards; D007074:Immunoglobulin G / Q000096:biosynthesis / Q000097:blood; D008070:Lipopolysaccharides / Q000276:immunology; D011785:Quality Assurance, Health Care; D014612:Vaccines / Q000592:standards*; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated; D014765:Viral Vaccines / Q000592:standards
chemical_list: D001428:Bacterial Vaccines; D007074:Immunoglobulin G; D008070:Lipopolysaccharides; D014612:Vaccines; D014613:Vaccines, Attenuated; D015164:Vaccines, Inactivated; D014765:Viral Vaccines