Influence of universal HBV vaccination on chronic HBV infection in Italy: Results of a cross-sectional multicenter study

Background and Aim: The universal hepatitis B vaccination for infants and 12-year-old adolescents (the latter limited to the first 12 years of application) was launched in Italy in 1991. Twenty-three years later we evaluated the impact of the vaccination campaign on the burden of HBsAg-positive chronic liver diseases (CLD). Material and Methods: A total of 513 HBsAg-positive chronic carriers referring to 16 Italian liver units were investigated and compared with HBsAg carriers enrolled in previous surveys. Results: The proportion of inactive carriers decreased from 20.0% in 2001 to 3.3% in 2014, while that of cirrhotic patients increased from 22.6% to 33.2%. Regarding the age class 0-33 (fully covered by HBV vaccination in 2014), the rate of inactive carriers decreased from the 21.7% in 2001 to 5.9% in 2014, that of chronic hepatitis from 17.5% to 5.2% and that of cirrhosis cases from 26.4% to 4.1%. Instead, in the over-60 age group the rate of inactive carriers increased from 22.8% to 41.2% and that of chronic hepatitis from 16.8% to 46%; the rate of patients with cirrhosis ranged from 5% to 8% in different studies. Conclusion: Twenty-three years after the introduction universal HBV vaccination in Italy, the clinical presentation of CLD had shown a shift toward older ages and more severe diseases.