Very high prevalence of TT virus (TTV) infection in general population of Japan revealed by a new set of PCR primers

Clear evidence for TT virus (TTV) to be a hepatitis virus remains unseen despite its origination from a hepatitis patient. Epidemiological studies on TTV have been limited more or less by the prematurity of the diagnostic systems. We sought after PCR systems that could detect TTV DNA more efficiently than those reported previously, and found that a PCR with new primers designated T801 and T935 was 10-100 times more sensitive than that with published primers NG061 and NG063. To our surprise, TTV DNA was identified by the new PCR system with T801/T935 in 92% of 100 individuals who visited our hospital for health screening, compared to 23% with NG061/NG063. Liver function test values were comparable between TTV DNA-negative and positive individuals, but mean age was younger in the former than in the latter: 29.7 +/- 6.9 versus 41.4 +/- 14.7 years (P < 0.05). Our results suggest that asymptomatic carriers of TTV are very common in general population of adults in Japan. (C) 1998 Elsevier Science Ireland Ltd. All rights reserved.