Infections and Immunoepidemiology Branch, Division of Cancer Epidemiology and Genetics, National Cancer Institute, Rockville, Maryland.
Demographic and Health Surveys, ICF International, Rockville, Maryland.
Department of Medicine, Stanford University School of Medicine, Palo Alto, California.
Department of Infectious Disease, Shanghai Jiao Tong University Affiliated Sixth People's Hospital, China.
Department of Microbiology and Immunology, Stanford University School of Medicine, Palo Alto, California.
Information Management Services, Calverton, Maryland.
Urban Health Study, University of California San Francisco.
Department of Medicine, Weill Cornell Medical College, New York.
People who inject drugs (PWID) are commonly exposed to hepatitis B virus (HBV) and hepatitis D virus (HDV). We evaluated the prevalence of HDV viremia among hepatitis B surface antigen (HBsAg)-positive PWID (n = 73) using a new quantitative microarray antibody capture (Q-MAC) assay, HDV western blot, and HDV RNA. HDV Q-MAC performed well in this cohort: anti-HDV, 100% sensitivity and specificity; HDV viremia, 61.5% sensitivity and 100% specificity. Hepatitis D viremia was present in 35.6% of HBsAg-positive participants and was more common in those with resolved compared to chronic hepatitis C (5.1% vs 0.6%; adjusted odds ratio, 9.80; P < .0001).