Epidemiological standardization of a test for susceptibility to mumps

An enzyme-linked immunosorbent assay (ELISA) for antibody to mumps virus is described. It is standardized with sera from putatively susceptible and immune populations. The ranges for 49 susceptible and 19 immune children were an optical density of -0.020 to 0.028 and 0.133 to 0.640, respectively. When compared with the microneutralization assay for evaluating vaccine responses, the ELISA appeared to be more sensitive while retaining its specificity. The failure rate after mumps vaccination in 301 children was 1.7% (5 of 301) by the ELISA and 12% (36 of 301) or 7.6% (23 of 301) by the microneutralization assay, depending on whether a high (30-100 50% tissue culture infectious dose [TCID₅₀]) or low (10-20 TCID₅₀) dose of virus was used.