Transfusion transmitted virus infection in patients on maintenance haemodialysis and in hospital workers

A newly discovered DNA virus, transfusion transmitted virus (TTV), was isolated from a post-transfusional hepatitis patient in Japan. A high prevalence (32-46%) of TTV infections in patients receiving maintenance haemodialysis (HD) has been reported but the occupational risk of TTV on HD units has not yet been determined. We determined the prevalence of TTV in workers in the same HD unit and the risk factors for TTV infection in HD patients, using logistic regression analysis. The prevalence of TTV DNA was 59.6% in 198 HD patients, significantly higher than that in the HD unit (13 of 39, 33.3%;P= 0.002) and non-HD healthcare workers (20 of 75, 26.7%; P= 0.001). A logistic regression analysis showed that male gender and negative test results for hepatitis G virus RNA were risk factors for TTV infection, but prior blood transfusion and duration of HD were not. Stepwise selection of multiple regression analysis showed that the presence of hepatitis C virus RNA was the only significant predictor for high serum ALT activity, and that the presence of TTV DNA was not. These results indicate that TTV is one of the prevalent human viruses transmissible either parenterally or nonparenterally in HD patients, but the occupational risk of TTV infection in HD unit workers is as low as in other healthcare workers. The pathogenic effects of TTV on the liver appear to be limited.