Evaluation of Measles Vaccine Immunogenicity and Durability Using A Pseudotyped Virus Neutralization Assay.

INTRODUCTION

This study aimed to establish a robust method for monitoring measles vaccine-induced immunity and assessing population-level serostatus.

METHODS

This study constructed a vesicular stomatitis virus (VSV)-based pseudotyped virus system expressing envelope proteins from seven major circulating measles genotypes (H1, B3, D4, D8, D9, D11, G3) and the Schwarz vaccine strain (genotype A), thereby enabling a high-throughput neutralization assay for antibody detection.

RESULTS

Vaccination induced a substantial increase in neutralizing antibody geometric mean titers (GMT) post-immunization (4,808 after the first dose; 5,326 after the second dose), with antibody levels remaining elevated in 4-year-old children (GMT: 3,834). Cross-neutralization activity against different genotypes varied by less than 6.4-fold, demonstrating broad protective immunity. However, 12% of adult sera tested were seronegative, revealing the presence of susceptible populations.

CONCLUSIONS

This study confirms the robust immunogenicity of the current measles vaccine and establishes a valuable tool for serosurveillance and long-term immunity assessment.