Introduction: We investigated 170 HBsAg-positive immigrants living in Italy for 1-7 years to ascertain whether they may have become infected in the host country.
Methods: Of 2032 adult immigrants interviewed, 1727 (85%) voluntarily adhered to a screening program for bloodborne or sexually transmitted infections. HBsAg was detected in 170 (9.8%) screened immigrants who completed the diagnostic, clinical and therapeutic process at the nearest clinic of infectious diseases. HBV molecular biology was performed applying a homemade technology. Phylogenetic signal of the datasets was obtained by a likelihood-mapping analysis using TreePuzzle.
Results: Of the 170 HBsAg-positive immigrants, 133 were inactive carriers, 29 had chronic hepatitis and 8 compensated cirrhosis. HBV genotype was identified in 109 of the 113 HBV-DNA-positive immigrants and HBV-genotype-E predominated (68.9%). Of these 109, 6 (5.5%) subjects showed an HBV genotype absent or extremely rare in their native country: HBV-genotype-E in three from Eastern Europe and in one from Sri Lanka, possibly acquired from other immigrants from sub-Saharan countries, HBV-genotype-D1 in one from Burkina Faso and one from Senegal, possibly acquired in Italy.
Conclusion: The data suggest that immigrants may acquire HBV infection in Italy and, therefore, HBV vaccination programs should be extended to all immigrants living in Italy.
Keywords: Chronic HBV infection; Genetic variability; HBV genotype; Hepatitis B virus; Phenotypic variation; Refugees; Undocumented immigrants.