Transfusion-transmitted virus infection in China: Prevalence in blood donors and in patients with liver diseases

Background: Prevalence of transfusion-transmitted virus (TTV) infection amo ng blood donors and in patients with liver diseases in China was studied. Methods: DNA was extracted from serum and amplified by seminested polymeras e chain reaction with reported primer sets from a conserved region of the T TV genome. Results: TT Virus DNA was detected in 55 of 196 blood donors (28%); 31% (40 of 127) in the north and 22% (15 of 69) in the south. TT Virus DNA was als o detected in 14 of 31 patients (45%) with non-A-non-G fulminant hepatitis and in eight of 25 patients (32%) with non-A-non-G chronic hepatitis. The r ate of TTV viraemia in these patients with liver disease was comparable to chat in blood donors. TT Virus DNA sequencing of 12 isolates showed that th e prevalence of genotype 2 was significantly higher than that reported in J apan (66.7 vs 2.6%, P<0.001). Furthermore, genotyping assays based on restr iction fragment length polymorphism were carried out on all 88 TTV DNA-posi tive samples. It was found that 42 isolates (47.7%) belonged to genotype 1 and 40 (45.5%) to genotype 2. It was of particular interest that the preval ence of genotype 1 in patients with non-A-non-G fulminant hepatitis was sig nificantly higher than that in blood donors (10/14 vs 22/55, P<0.05). Conclusions: The data indicate that TTV infection is common in China and th at the pathogenic potential of TTV toward the liver (if any) may differ bet ween genotypes. (C) 1999 Blackwell Science Asia Pty Ltd.