Comparative analysis of monoclonal antibody based enzyme immunoassay, modified genome electrophoresis & electron microscopy procedures for rotavirus diagnosis from faecal specimens

Background & objectives: Reliable and rapid diagnosis of rotavirus infectio n is necessary for patient management. Several newly introduced commercial enzyme immunoassays (ELISAs) have been evaluated using direct electron micr oscopy (DEM) with or without direct ultracentrifugation as the standard ref erence method, and have shown varying results. Methods : In the present study we compared the diagnostic efficacy of the t hree methods viz., monoclonal antibody (MAb) ELISA, modified polyacrylamide gel electrophoresis (PAGE) and DEM without ultracentrifugation in the dete ction of rota-viruses from 211 stool specimens. The data were analysed by t wo latent class model (2LC) in the absence of a gold standard reference met hod. Results : Rotavirus was detected in 42 specimens by NIAb-ELISA; in 40 speci mens by PAGE and in 33 specimens by DEM. The estimates of sensitivities and specificities of the three methods were analysed by 2LC method. The analys is revealed no significant variation among the three methods. However, DEM was found with a comparatively lesser sensitivity over the other two method s. Interpretation & conclusions : Though DEM was found to be relatively less s ensitive than the other two methods, the differences were not significant, and all the three methods were highly specific. Moreover, DEM has the addit ional advantage of detecting non-group A and other gastroenteritis viruses. The findings suggest the use of highly sensitive and specific NIAb-ELISA a nd PAGE in parallel to detect group A, non-group A and atypical rotavirus i nfection in the population.