Did a little research on AuAg hepatitis after it was mentioned in connection with the DIA posts (time capsule and AuAg stone pics).

So Au stands for Australia and Ag is for antigen. AuAg was identified from an Australian aboriginal population during some transfusion medicine studies. No link was made to hepatitis at the time. Later the link between this antigen was made in a case where a child who had previously been tested became positive for the ag and developed hepatitis at the same time. It was proved that the presence of the ag was synonymous with hepatitis B infection. It is recognized today as HBsAg (hepatitis B surface antigen).

So not associated with a super virulent hepatitis. Just a well known hepatitis marker that is routinely used to diagnose hepatitis infection.