An 18 yr old previously well male Taiwanese was admitted with malaise, anorexia, and jaundice for two weeks. Results of liver tests were compatible with acute hepatitis. On day 1, he was seronegative for HBsAg, IgM anti-HAV, IgM anti-HBc, IgM anti-CMV, and IgM EBV capsid Ab, but positive for anti-delta in association with anti-HBc and anti-HBs. At follow up on day 5 HBsAg converted to positive ...