Self-contained enzymic membrane immunoassay for detection of rotavirus antigen in clinical samples.

A self-contained enzymic membrane immunoassay (SCEMIA) system has been developed for the detection of viral antigens in clinical samples. The assay system makes use of antiviral antibodies bound to a nylon membrane, a flow-through washing procedure, and a clearly visible endpoint of the enzymic reaction. A SCEMIA system with antibodies against rotavirus detected rotavirus antigen, within 15 min, in all faecal samples from children with gastroenteritis that were positive for antigen in a standard microplate enzyme immunoassay, which took 4 h to complete. In addition, the SCEMIA could detect rotavirus in faecal samples collected from infected individuals both before and after antigen could be detected by a standard immunoassay system. Rotavirus antigen was not detectable in control children who did not have evidence of rotavirus infection. SCEMIA systems are an accurate, rapid, and inexpensive means for the practical diagnosis of viral infections in human beings.