Rapid detection of human group C rotaviruses by reverse passive hemagglutination and latex agglutination tests using monoclonal antibodies

Reverse passive hemagglutination (RPHA) tests and a latex agglutination test with monoclonal antibodies (MAbs) were developed for the rapid detection of noncultivatable human group C rotaviruses. For RPHA tests, two MAbs, MAb 5A12 recognizing the outer capsid and MAb 13A3 recognizing the inner capsid, were separately used for the coating of sheep erythrocytes (SRBCs). Forty-six fecal samples were examined to confirm the practicality of the tests. As a result, there was concordance between the RPHA test with SRBCs coated with MAb 5A12 and polyacrylamide gel electrophoresis of viral RNA (RNA-PAGE) in 44 (95.6%) of 46 samples, while the diagnoses by the RPHA test with SRBCs coated with MAb 13A3 were in complete agreement with those by RNA-PAGE. Furthermore, a latex agglutination test with MAb 13A3 was also developed, and this test was fast enough and sensitive enough to successfully detect the viruses from most fecal samples within 2 min. The present procedures would be useful for the diagnosis of human group C rotavirus infections in clinical laboratories which are not well equipped. Rotaviruses are the most common causative agent of gastroenteritis in infants and young children in many coun-tries (11). Until recently, it was believed that there was only one rotavirus group and that all rotaviruses shared a group-specific antigen. However, a number of viruses which are morphologically similar to rotaviruses but do not share the group-specific antigen and usual genome profile generally associated with ordinary rotaviruses have been identified (16, 17). These distinct rotaviruses, atypical rotaviruses, ar