Hepatitis A virus in the liver and intestine of marmosets after oral inoculation.

A total of 12 seronegative marmosets (Saguinus mystax) were inoculated orally with hepatitis A virus (HAV) and sacrificed at 3- to 4-day intervals. Tissues from the livers, intestines, mesenteric lymph nodes, and spleens were obtained for immunofluorescence studies, and bile and intestinal contents were obtained for enzyme-linked immunosorbent assay studies. Two marmosets sacrificed on days 34 and 41 after inoculation developed antibody to HAV and demonstrated HAV in their livers but not in any part of their intestinal tissues. None of the remaining marmosets sacrificed from days -3 to 31 survived long enough to develop antibody to HAV, but an additional two marmosets, which were sacrificed on days 21 and 31, demonstrated HAV in their livers and also in bile but not in the intestinal tissues or their contents. The mesenteric lymph nodes and spleens were negative for HAV by immunofluorescence in all the marmosets. No evidence of HAV replication was demonstrated in any part of the intestine at any time during the incubation period or during acute illness in the marmosets inoculated orally with HAV. The shedding of HAV in stools in the late incubation period can be explained by excretion of HAV from the livers with the bile.