Evidence for a new rotavirus subgroup in India.

Monoclonal antibodies specific for rotavirus subgroup 1 (SG1) and subgroup 2 (SG2) were used to analyse by enzyme immunoassay (EIA) the subgroups of human rotavirus isolates obtained from three different parts of India during the period September 1985 to July 1987. We identified one isolate which failed to react with either SG1 or SG2 specific monoclonal antibodies, although it reacted well with a monoclonal antibody specific for group A rotaviruses. This finding suggests that it belongs to a new rotavirus subgroup. Further, another isolate was found to belong to SG1 although it had a 'long' electropherotype.