Detection of rotavirus in the intestine, liver, and pancreas (A) and in blood cells, serum, and spleen (B) of male and female infant NOD mice inoculated orally with RRV. RRV was detected by culture followed by EIA and by direct EIA. In panel B, infectious RRV was detected by culture then EIA in blood cells and spleen. Blood cells that contained infectious RRV also were positive for RRV antigen by direct EIA, and no other blood cell samples contained RRV antigen detectable by EIA. Rotavirus antigen was detected in serum by direct EIA, but infectious RRV was not detected in serum by culture then EIA. The number of mice examined at each day postinfection for each sample type (when these differed between sample types) is indicated above each panel.