Group A bovine rotavirus: diagnosis and antigenic characterization of strains circulating in the Argentine Republic, 1994-1999]

Group A Bovine Rotavirus (BRV) has been identified as a major cause of neonatal diarrhea in cattle. The study was aimed to determine the prevalence of BRV and to antigenically characterize the G-types of circulating strains in dairy and beef herds in Argentina. A total of 1129 stool samples from diarrheic calves was analyzed from 1994 to 1999. The samples were initially screened for RV by ELISA and PAGE, and then G-typed using monoclonal antibodies (Mab) directed against G1, G2, G3, G6 and G10-specific epitopes. Forty percent (452/1129) of the samples were positive for RV by ELISA, while 24.7% (279/1129) were also positive for PAGE. VP7 was detected in the 70.5% (319/452) of the positive samples using a broadly reactive Mab (C60); 32.6% (104/319) were G6, 15.4% (49/319) were G10, and 6% (19/319) were G1. However, 46.1% (147/319) of the samples remained untypable. Rotavirus diarrhea prevalences were comparable in beef and dairy herds (87.3% and a 74.4%, respectively). Finally, G6 was the most prevalent G-type circulating in beef herds while G10 prevailed in dairy herds. A better understanding of RV epidemiology will contribute to the optimization of current vaccines and prevention programs of RV diarrhea in calves.