Sensitivity and reproducibility of enzyme immunoassay for measles virus antibody detection

The Immunoenzymatic ELISA method has been applied to the detection of antibody to measles virus by using a single serum dilution. The reproducibility has been tested over three groups of sera negative, intermediate and strongly positive, in 48 different assays. The standard deviations and the variation coefficients are reported which show very good reproducibility both within and between runs. As regard sensitivity ELISA has proved more sensitive than Haemagglutination Inhibition (HAI) by testing sera both from healthy and vaccinated individuals. Variation of the absolute O.D. values has been found by using two different lots of plates. The use of control sera with various titres is recommended, and a reference scale may be valuable for normalization of the results.