TT virus infection in intravenous drug users

Our group has investigated 201 intravenous drug users for the presence of TTV DNA by means of polymerase chain reaction (PCR). The majority of the individuals tested were male, their age ranging from 16 to 63 years, and the duration of intravenous drug use from one to 40 years. TTV DNA was present in 62 of the 201 IVDUs (30.8%) with its prevalence on the ascent between the age groups below 20 and those between 21 and 30 years, as well as between the groups below 60 and between 60 to 120 months' duration of drug intake, respectively. When tested again after 9 months, nine IVDU (23.7%) were found TTV negative by PCR hinting at potential immunological clearance. Our control group comprised 200 healthy blood donors, 7% of whom were found to harbor TTV DNA in an age-dependent fashion, as observed with the IVDU. From the liver function tests performed we could not detect any statistically significant difference regarding ALT elevation observed in TTV-positive compared with TTV-negative individuals. To date, TTV does not appear to cause any serious liver disease in the majority of cases examined.