Trivalent Oral Polio Vaccine

Abstract

Titrations of antibodies against the 3 polio viruses by the metabolic inhibition test were determined before and after feedings of the trivalent mixture. Conversion rates after a single dose were disappointing for Type 1 antibody, but conversion rates after a second dose were 92%. In triply susceptible subjects, that is, in those non-immune to all 3 types of polioviruses, the conversion rate after 2 feedings of trivalent vaccine was 92% for Type 1, and 100% for Types 2 and 3. The advantages of using trivalent vaccine rather than monovalent vaccines are discussed.