To the Editor—We read with interest the article by Patel and colleagues [1], which reported an unexpected 33% prevalence of anti–hepatitis delta virus antibodies (anti-HDV-Abs) in a large and representative US household population. Estimates of 400 000 individuals with hepatitis delta in the United States could be drawn from the study. These figures are somewhat in line with recent claims of a global burden of up to 60 million people with hepatitis delta [2]. As highlighted by Patel et al [1], high-risk groups were not represented or were underrepresented in their survey of 16 143 US adults. Hepatitis delta is...