infection , defined according to the presence of virus and viral antigens in intestinal tissues and by seroconversion in the immunoglobulin m ( igm ) isotype as determined by enzyme-linked immunosorbent assay with sa-11 antigen , was observed for all age groups ( neonatal to adult ) , even in the presence of virus-specific serum or intestinal immunoglobulins .
C0003342
viral antigens
C0003320
antigen