Clearance of hepatitis TT virus infection among thalassemia children and IVDU.

The novel transfusion transmissible hepatitis virus TTV first isolated by a group from Japan has predominantly been detected in members of groups at high risk for contracting blood borne viruses. Aside from elevated liver enzymes, the symptoms associated with its infection have been reported to range from asymptomatic to hepatic failure. The purpose of the present study was to determine if and to what extent the host's immune response is capable of clearing TTV infection. Hence, we extracted DNA from sera obtained from altogether 201 intravenous drug users (IVDU) and 80 thalassemia children--both groups at high risk of parenteral exposure--and performed PCR using semi-nested primers. Those positive for TTV DNA were once again subjected to PCR after approximately one year in order to determine how many still harbored the virus. Our results showed TTV DNA to be absent in merely 20.6% of the formerly positive IVDU, whereas it was still present in all the thalassemia children who could be tested for the second time. Based on the small sample size and the high-risk environment, these results ought to be interpreted with caution and definitely merit further investigation.