HAV infection in chronic liver disease: a rationale for vaccination.

We report the conduct and results of a systematic search of the literature to assess whether exposure to HAV could induce a fatal deterioration of liver diseases. We assessed 30 studies and found evidence of progressive decrease of natural immunity against HAV in Italy. HAV vaccine seems as safe in chronic liver diseases than in general population. On the basis of the evidence we recommend that subjects with chronic liver disease should be vaccinated against HAV, especially if younger than 40 years.