[What is next in antirabies immunization?]

Area of Science:

• Immunology
• Vaccinology
• Public Health

Context:

• Rabies prevention relies on effective vaccines inducing robust antibody responses.
• Different vaccine administration routes (intradermal vs. subcutaneous) may influence immunogenicity.
• Human diploid cell culture vaccines and tissue culture vaccines represent distinct vaccine technologies.

Purpose:

• To compare the immunogenicity of an intradermal human diploid cell culture rabies vaccine (Rabivac) with a subcutaneous tissue culture vaccine (Vnukovo SAD-32).
• To evaluate the impact of immunization route and duration on antirabic antibody titres.
• To assess antibody responses across different age groups, particularly in older adults.

Summary:

• Subjects receiving the intradermal Rabivac exhibited significantly higher geometrical mean titres of specific antirabic antibodies compared to those given the subcutaneous Vnukovo SAD-32 vaccine.
• Both short and long immunization schedules were assessed for the subcutaneous route.
• A notable finding was the low mean antibody titres and high incidence of zero values in individuals over 50 years old, irrespective of the vaccination method.

Impact:

• The study suggests intradermal vaccination may be a more effective route for generating higher antirabic antibody titres.
• Findings highlight a potential immunodeficiency or reduced vaccine response in older populations, warranting further investigation and potentially tailored vaccination strategies.
• Results contribute to understanding vaccine efficacy and optimizing rabies prevention protocols, especially for vulnerable age groups.