Epidemic hepatitis-associated antigen (milan antigen). Study on normal population and sporadic acute viral hepatitis.

Five epidemics of A (short incubation) or IH hepatitis in children have been studied in Italy and England with the collaboration of Sheila Sherlock's group of the Royal Free Hospital, London.1Sera from the patients have been repeatedly negative for the Australia antigen. A new antigen has been detected by gel diffusion using a new antiserum obtained from a multiply transfused patient; this is the epidemic hepatitis-associated antigen (EHAA). The EHAA was found in fresh sera of 66.5% of the patients and 90% of those tested during the first two weeks of illness. This antiserum (T or Milan) produces a precipitin line at the gel diffusion test when it reacts with sera from patients with viral hepatitis of both long or short incubation periods. This means that the T or Milan antiserum contains at least two antibodies, one specifically related to the antigen or antigens associated with SH2