Validation and comprehensive analysis ofStreptococcus pneumoniae IgG WHOenzyme linked immunosorbent assay in anIndian reference laboratory: supplementary data

Monitoring serotype-specific IgG levels against pneumococci is crucial for assessing immunity, vaccineefficacy, and evaluating vaccination programs. The WHO ELISA for pneumococci is a standardized assayensuring consistency in testing and comparability of results across laboratories. It involves a rigoroustesting process to confirm accurate, precise, and reliable detection of antibodies. We validated theprotocol for 13 pneumococcal serotypes by assessing its specificity, reproducibility (coefficient of variation≤15%), repeatability (coefficient of variation ≤20%) , accuracy, lower limit of quantification, stability,and robustness. We found these parameters were within acceptable ranges and showed excellentperformance. Our findings imply that the method employed is appropriate for evaluating 13 valentpneumococcal conjugate vaccine which is introduced in the national immunization program by comparingpre-and post-vaccination IgG response.