Response to experimental challenge in persons immunized with different rubella vaccines

Area of Science:

• Immunology
• Virology
• Vaccinology

Background:

• Rubella virus infection poses a public health concern, necessitating effective vaccination strategies.
• Evaluating the immunogenicity and safety of different rubella vaccine formulations is crucial for optimizing public health interventions.

Purpose of the Study:

• To compare the immunogenicity and safety of three rubella vaccines (HPV-77-DE-5, Cendehill, and RA-27/3) in adolescents.
• To assess the antibody response and side effects following primary immunization and experimental rubella virus challenge.

Main Methods:

• 113 adolescent volunteers (13-17 years) received one of three rubella vaccines.
• Vaccine administration routes included subcutaneous and intranasal.
• Volunteers were experimentally challenged with rubella virus a year after primary immunization.
• Serologic responses were measured using complement fixation (CF), hemagglutination inhibition (HI), and neutralizing and sensitizing antibody tests.

Main Results:

• The RA-27/3 vaccine, administered either subcutaneously or intranasally, showed the highest immunogenic potential.
• Side effects ranged from 16% (Cendehill) to 32% (RA-27/3 intranasal).
• Booster responses after challenge were highest in Cendehill vaccinees (67%) and lowest in RA-27/3 vaccinees (7-11%), indicating a strong primary response with RA-27/3.

Conclusions:

• The RA-27/3 rubella vaccine exhibits superior immunogenic potential compared to HPV-77-DE-5 and Cendehill vaccines in adolescents.
• RA-27/3 vaccine is safe and effective, eliciting a strong primary antibody response that may reduce the need for boosters after subsequent exposure.
• Findings support the use of RA-27/3 as a highly immunogenic rubella vaccine option.