A Study on the Prevalence of Transfusion Transmitted Virus by Seminested-PCR Among Patients With Thalassemia Major

Patients with thalassemia major are at increased risk of blood borne viral infections. TT virus (TTV) is a single stranded circular DNA virus which is involved in the development of post-transfusion non A– C hepatitis. The aim of the present investigation was to assess the prevalence of TTV infection among these patients. Two hundred and fifty patients with thalassemia major were the subject of this study. TTV DNA was amplified from plasma by seminested polymerase chain reaction (PCR) with TTV–specific primers (NGO59, NGO61, NGO63) from the conserved regions in ORF1 (This segment consists of 271 bp). The data collected were compared with 250 blood samples taken from healthy blood donors in the central blood bank. Data were analysed using the 2 and Fisher’s exact test, as appropriate. The prevalence of TTV DNA was significantly higher in thalassemic patients (57.2%, 143/250) than in healthy controls (20%, 54/250). The prevalence of positive TTV DNA was found to increase with age and number of transfusions (p<0.01 and p<0.04 respectively). There is no statistically significant association between TTV DNA prevalence and the gender. TTV is highly prevalent both among thalassemic patients living in Khouzestan province of Iran who undergo multiply transfused as well as in healthy blood donors. Based on these observations, it is likely that the parental route may not be the only mode of spread TTV. Okamoto et al. have previously shown that TTV DNA is present in faeces, which may further supports the faecal–oral route of viral transmission.