Trends in Hepatitis D Virus Prevalence Among HBsAg-Positive Individuals With and Without HIV in Italy: A Converging Epidemiology

Background and aims: Hepatitis D virus (HDV) infection has historically been more prevalent among people with HIV (PWH) due to shared transmission routes. Whether HIV status still identifies a subgroup at higher risk of HDV in contemporary settings remains unclear. Methods: We performed two cross-sectional analyses assessing anti-HDV prevalence among HBsAg-positive PWH enrolled in the ICONA cohort in 2009-2012 and 2019-2023, compared with HIV-negative individuals from the MASTER and PITER cohorts. Results: Anti-HDV prevalence among PWH declined from 19.1% to 12.5%, converging with that observed in HIV-negative individuals (12.7%). Injection drug use markedly decreased over time among PWH and remained the strongest determinant of HDV infection. In multivariable analyses, HDV seropositivity was associated with age, injection drug use, and birth outside Italy, but not with HIV infection in the contemporary period. Conclusion: These findings indicate that HIV infection is no longer independently associated with HDV infection in this setting and support universal HDV screening strategies.