Prevalence of Hepatitis D in the United States.

Background: Hepatitis D virus (HDV) causes the most severe form of viral hepatitis and exclusively infects people who are also infected with hepatitis B virus (HBV). The global incidence of HDV is estimated to be 5.9%-14.6% of HBV infected individuals, however, the prevalence in the United States is unknown.

Methods: In this study, the prevalence of HDV in HBV infected individuals was determined by testing 1104 samples from a national laboratory that were positive for hepatitis B surface antigen with the anti-HDV total antibody ELISA from International Immuno Diagnostics.

Results: The prevalence of HDV using the described approach was 1.2% of HBV positive samples. HDV positivity did not correlate with HBV viral load, although the sample size may be insufficient to detect such an effect. HDV RNA, which is present during active infection, was detected in 33% of anti-HDV positive samples.

Conclusions: This provides a more reliable estimate for HDV prevalence in the United States that is lower than estimates from previous smaller studies and meta-analyses. A reliable estimate of HDV prevalence is increasingly important due to the advent of several new HDV therapies and the growing consensus among clinicians and professional societies that all HBV infected individuals should also be screened for HDV.