Evaluating Potency Values of Monovalent Rotavirus Vaccine: Comparison between Crystal Violet Staining and Immunoperoxidase Staining

Abstract

A human rotavirus vaccine will be included in the National Expanded Programme on Immunization in 2015. Thus, quality control of the vaccine is required, particularly in the control of potency values to verify vaccine efficacy in the market. The objective of this study was to compare two staining methods for assessing vaccine potency, the crystal violet and the immunoperoxidase, in the detection of rotaviral infection of MA104 cells. It was found that immunoperoxidase method yielded higher sensitivity than that of crystal violet. In addition, it showed compatible accuracy with the specification of the vaccine manufacturer which specified that the potency values should be higher than 6 logCCID₅₀/dose/ 1.5 ml. The immunoperoxidase staining method also had high precision as observed by the nonsignificant variations of the outcomes of two analyses. Thus, immunoperoxidase staining was a more suitable method for lot-release control of rotavirus vaccines to support the National Expanded Programme on Immunization.