自 1997年底日本学者Ｎｉｓｈｉｚａｗａ等[1] 报道发现一种可能与输血后肝炎相关的新病毒———ＴＴ病毒 (ＴＴＶ)以来 ,国内外学者对ＴＴＶ的基因序列、流行病学及临床表现作了大量的研究 ,现将研究进展综述如下。1　ＴＴＶ的发现及其病原学　　长期以来 ,人们一直在寻找非甲 Since the Japanese scholar Nishizawa et al [1] reported late in 1997 that a new type of hepatitis virus (TTV) possibly related to post-transfusion hepatitis has been reported by domestic and foreign scholars on the gene sequence, epidemiology and clinical manifestations of TTV A large number of studies, the research progress are summarized below. 1 TTV’s Discovery and Its Etiology People have long been searching for non-A’s