Hofmeister MG, et al. - This investigation draws on 2013-2016 data from the National Health and Nutrition Examination Survey (NHANES) to determine the prevalence of hepatitis C virus (HCV) among all adults aged ≥18 years in the US. A combination of literature reviews and population size estimation approaches were used to evaluate the HCV prevalence and population sizes for four additional populations: incarcerated people, unsheltered homeless people, active-duty military personnel, and nursing home residents. Researchers observed that over 2 million people in the US had current HCV infection during 2013-2016. HCV antibody prevalence might have increased, while RNA prevalence might have reduced, probably a reflection the combination of the opioid crisis, curative treatment for HCV infection, and mortality among the HCV-infected population vs past estimates based on similar methodology.