Abstract: Objective To study the situation of infection with transfusion transmitted virus (TTV) and its transmission through sexual contacts in STD patients. Methods Serum TTV DNA was tested by nested-PCR in 237 STD patients and 80 healthy married controls, and the sexual behaviors were investigated among the STD patients. Results (1) The positive rate of TTV DNA in the 237 STD patients was 19.41% (46/237), and it was significantly higher than that in the controls (2.5%, 2/80,P<0.005). (2) There was no significant difference in positive rates of TTV DNA between male STD patients (20.59%) and female patients (17.82%) (P>0.05). (3) The positive rates were relatively high in patients with syphilis (29.41%), genital herpes (30.43%), co-infection of syphilis and nongococcal urethritis (NGU) (33.33%), syphilis and condyloma acuminatum (CA) (42.86%) and genital herpes and CA (33.33%), whereas the positive rate of patients with NGU was as low as 10.87%. (4) There was a significant difference in TTV DNA positive rate between 28 STD couples (28.57%, 16/56) and 11 healthy couples (4.55%, 1/22) (P<0.05). (5) Out of the STD patients with positive TTV DNA, 21 patients had a history to visit sex workers for more than 6 months, whereas there were only 7 patients with such history in the STD patients with negative TTV DNA (P<0.005). The mean number of sexual partners was 17.20 in STD group with positive TTV DNA, and 7.86 in negative TTV DNA STD group (P<0.001). Conclusions There is a relatively high TTV infection in the STD patients. The STD patients with a longer history to visit sex workers or more sexual partners are likely to have TTV infection, suggesting that sexual contact is one of transmission routes of TTV.

Key words: Transfusion-transmitted virus, Sexually transmitted diseases