Acute Hepatitis A Infection in Hepatitis B Chimpanzee Carriers†

Two hepatitis B virus carrier chimpanzees which were superinfected with hepatitis A virus developed acute hepatitis followed by the production of antibodies to hepatitis A virus. The Southern blot technique employed to monitor liver hepatitis B virus DNA revealed that the amount of viral DNA in both animals was significantly reduced during the acute phase of hepatitis A infection. The levels of plasma hepatitis B DNA polymerase activity were also reduced in one chimpanzee. The high titers of HBsAg in the circulation remained unchanged throughout the study, and antibodies to the surface antigen and to e antigen were not detected. The morphological lesions in the liver were severe in one chimpanzee from whom one specimen showed both periportal focal necrosis and zonal parenchymal necrosis.