TT virus genotype changes frequently in multiply transfused patients with hemophilia but rarely in patients with chronic hepatitis C and in healthy subjects.

TTV seems not to have clinical relevance. However, the publication is very important since it clearly shows that the virus inactivation of factor VIII and IX concentrates, at least those used in the patients investigated, is not totally effective in order to inactivate unenveloped viruses.

– V. Kretschmer.