According to the National Health and Nutrition Examination Survey (NHANES), the prevalence of chronic hepatitis B virus (HBV) infection based on positive hepatitis B surface antigen (HBsAg) is estimated to be 0.3% overall,1,2 0.15% in US-born individuals, and 1.28% in non–US-born individuals, with the highest prevalence among non–US-born Asian individuals (3.9%).2 However, the true prevalence is likely higher because high-risk populations are not adequately represented in the survey. A study that used meta-analytic methods to determine country-specific pooled HBV prevalence rates multiplied by the number of non–US-born persons living in the US in 2009 by country of birth estimated that a total of 2.2 million persons with chronic HBV infection were living in the US3—much higher than the NHANES estimate of 862 000.1 Despite the availability of safe and effective vaccines, the prevalence of HBV infection among young adults in the US has been increasing in recent years, possibly because of the low prevalence of immunity among adults and the ongoing opioid epidemic.4,5