Evaluation of assay systems for the detection of rotavirus in stool specimens

We tested 41 rotavirus positive and 42 negative specimens as determined by electron microscopy. The assays systems used were an indirect NIH-ELISA, Meritec-Rotavirus, Virogen Rotatest, and Rotazyme II. Meritec and Virogen (latex agglutination assays) were the most sensitive tests, detecting 95% of the positive specimens. The NIH-ELISA detected 81% and Rotazyme detected 63%. Rotazyme was the most specific (100%), followed by the NIH-ELISA (95%) and the two latex agglutination systems (91%). To determine the level of rotavirus detection, we tested three systems against serial two-fold dilutions of ten positive stools. The NIH-ELISA detected rotavirus in an average dilution of 1:723. Rotazyme detected rotavirus in an average stool dilution of 1:366, and Meritec showed an average of 1:164. Rotavirus strains representing serotypes 1-4 were also tested. Meritec was able to detect all four serotypes. Virogen did not react with serotype 2 strains. The NIH-ELISA and rotazyme were unable to detect serotype 3. These data suggest that some latex agglutination assays may be a useful alternative to ELISAs in the clinical laboratory.