INFECTIOUS-HEPATITIS - EVIDENCE FOR 2 DISTINCTIVE CLINICAL, EPIDEMIOLOGIC, AND IMMUNOLOGICAL TYPES OF INFECTION (REPRINTED FROM JAMA, VOL 200, PG 95-103, 1967)

The identification of two types of infectious hepatitis with distincti ve clinical, epidemiological, and immunological features provided an e xplanation for the occurrence of second attacks of the disease. One ty pe resembled classical infectious hepatitis (III); it was characterize d by an incubation period of 30 to 38 days, a relatively short period of abnormal serum transaminase activity (3 to 19 days), a consistently abnormal thymol turbidity, and a high degree of contagion. The other type resembled serum hepatitis (SH); it was characterized by a longer incubation period (41 to 108 days), a longer period of abnormal transa minase activity (35 to 200 days) and a relatively normal thymol turbid ity. Contrary to commonly accepted concepts, the SH type was moderatel y contagious. Patients with IH type were later proved to be immune to the same type. Patients with the SH type were not immune to the IH typ e infection.