[Comparison of enzyme immunoassay, counterimmunoelectrophoresis and polyacrylamide gel electrophoresis for the diagnosis of rotaviruses].

Detection of human rotaviruses by enzyme-linked immunosorbent assay (ELISA), provided by the World Health Organization, in 100 stool specimens was compared with the sensitivity of detection by counterimmunoelectrophoresis (CIED) and polyacrylamide gel electrophoresis (PAGE). Table 1 shows that 34 samples were found to contain rotavirus antigens by ELISA and in other 4 specimens false negative results were observed in the ELISA confirmatory test because of high antigen concentration. The ELISA confirmatory test was repeated with the 4 samples diluted 1/40 and they became positives. It was found that, of the 38 ELISA positive samples, 35 were positive by PAGE (92%) and 24 by CIED (63%). Detection of human rotaviruses in stools by PAGE were almost as sensitive as ELISA, but the direct visualization of viral RNA fragments, provided a distinct advantage since no confirmatory test was necessary. Besides, the surveillance of rotavirus electrophoretypes constitutes a very useful tool in epidemiological studies, in order to the future possible use of a rotavirus vaccine in our country. By the other hand, it was found CIED less sensitive than ELISA and PAGE. This disadvantage might be tolerated in a diagnostic setting, only if no other test was available for rotavirus diagnosis.