Changing patterns of hepatitis B infection in Italy and NAT testing for improving the safety of blood supply.

In Italy, as in most industrialized countries, the burden of hepatitis B has progressively declined in recent decades as a consequence of general improvements in hygiene and standard of living, the introduction of several public health measures, refinement in blood screening and the implementation of specific vaccination programmes. Universal hepatitis B vaccination for all infants and adolescents as well as individuals at increased risk has resulted in considerable progress towards prevention and control of HBV infection. The residual risk of transmitting blood-borne viruses through transfusion is currently very low. Nucleic acid testing can shorten the window period and, consequently, further reduce the risk of viral transmission. Blood donor screening for HCV by NAT was initiated in Italy in 2001 and became mandatory in June 2002. NAT for HIV is currently mandatory in four regions, not mandatory but almost universally performed in another thirteen regions, and not yet introduced in the remaining four regions. NAT for HBV is currently mandatory in four regions and under evaluation in the remaining. NAT for HBV may be a useful tool in detecting acute viral infections in the window phase as well as the occult infections. Its efficacy in improving the safety of blood supply is expected to be higher in countries with intermediate/high endemicity, where anti-HBc antibody screening cannot be routinely performed. There is agreement that, at present, the implementation of HBV DNA testing will not allow for discontinuation of screening for HBsAg.