Hepatitis C Surveillance in the United States: Past, Present, and Future

Abstract

Data from 3 US public health surveillance systems indicate that an estimated 67 400 people acquired hepatitis C virus infections in 2022, 2.2 million adults had hepatitis C during January 2017-March 2020, and 12 717 people died in 2022 from hepatitis C-related causes, despite the availability of curative treatment since 2013. The 3 surveillance systems that provided these data-the National Notifiable Diseases Surveillance System, the National Health and Nutrition Examination Survey, and the National Vital Statistics System-were selected to monitor progress toward elimination of hepatitis C as a public health threat in the United States by 2030. However, some limitations of these surveillance systems compel the use of additional data sources with more timely information for the general population and for populations with higher incidence, prevalence, or mortality of hepatitis C, such as those experiencing homelessness, incarceration, or injection drug use. Commercial laboratories, health systems, and programs serving these populations could provide such data. This topical review of hepatitis C surveillance describes the history, long-term trends, and recent investments in public health surveillance for hepatitis C. Strengthening and modernizing the hepatitis C surveillance workforce and systems, improving data system interoperability, linking complementary data sources, and leveraging multiple data systems can aid in the measurement of public health efforts to meet hepatitis C elimination goals.

Keywords: data modernization; hepatitis C; public health; surveillance; trends.

Figure 1.

Trends in reported cases of unspecified hepatitis, non-A/non-B hepatitis, confirmed and probable acute hepatitis C, past or present hepatitis C, and chronic hepatitis C from the National Notifiable Diseases Surveillance System, United States, 1974-2021. (A) Reported cases of unspecified hepatitis, non-A/non-B hepatitis, and acute hepatitis C, 1974-2022. The non-A/non-B hepatitis case definition was established in 1990 as one of many newly standardized case definitions for notifiable diseases. Acute hepatitis C case definitions were published for 1995 and 1996. Case definitions for acute hepatitis C were revised for 2000, 2004, 2007, 2011, 2012, 2016, and 2020 (eTable 1 in Supplement). Surveillance reports published combined hepatitis C and non-A/non-B hepatitis case counts from 1994 through 2002 because jurisdictions implemented the acute hepatitis C case definitions at different times (eTable 2 in Supplement). (B) Newly reported cases of past or present hepatitis C and chronic hepatitis C, 2009-2022. Case definitions for hepatitis C, past or present, were published for 2003, 2005, 2011, and 2012. Case definitions for chronic hepatitis C were published for 2010, 2016, and 2020 (eTable 1 in Supplement). Surveillance reports published annual case counts for hepatitis C, past or present, from 2009 through 2015 and for chronic hepatitis C since 2016 (eTable 2 in Supplement). Data source: National Notifiable Diseases Surveillance System.

Figure 2.

Published estimates in millions of people with detected hepatitis C virus (HCV) RNA and selected protocol changes for the National Health and Nutrition Examination Survey (NHANES), United States, October 1988–August 2023. Data source: NHANES. Based on data for HCV RNA from NHANES collected during 1988-1994 and 1999–March 2020, 1 or more estimates of the prevalence of current, likely chronic, HCV infection were abstracted from each of 21 studies. The number in millions of people with current HCV infection (HCV RNA detected) is shown, with 95% CIs if available from the study. Studies used different methods: modeling the prevalence by using NHANES with other data sources, such as mortality from overdoses; weighting the estimates by using the survey weights available in the datasets; adjusting the survey weights to account for missing HCV antibody or HCV RNA results; or augmenting the estimates with information from studies of populations that were excluded or underrepresented in NHANES. Studies used different age groups (eg, ≥6, ≥12, ≥18, or ≥20 y). One study did not specify the age group used, and another limited the analysis to NHANES participants with elevated alanine transaminase levels. The hepatitis C laboratory and interview protocols changed during this time, as did the NHANES sampling design and data selected for public release. A major redesign of NHANES launched in 2025 (eTable 3 in Supplement). Abbreviations: ALT, alanine aminotransferase; anti-HCV, antibody to HCV infection; INNO-LIA, INNO line immunoassay; ELISA, enzyme-linked immunosorbent assay; RT-PCR, reverse-transcription polymerase chain reaction.

Figure 3.

Trends in reported deaths with any viral hepatitis, hepatitis C, and other and unspecified hepatitis from the National Vital Statistics System, United States, 1979-2022. Data source: National Vital Statistics System. (A) Deaths with underlying causes of any viral hepatitis and other and unspecified hepatitis during 1979-1998 and hepatitis C during 1996-1998 were coded by using the International Classification of Diseases, Ninth Revision (ICD-9). In preparation for the transition to the International Classification of Diseases, Tenth Revision (ICD-10) in 1999, deaths during 1996-1998 were recoded by using a crosswalk from ICD-9 to ICD-10 coding. (B) Deaths with any viral hepatitis and hepatitis C as 1 of multiple causes of death, 1999-2022. Beginning in 1999, deaths with hepatitis C as 1 of multiple causes of death were published instead of deaths with hepatitis C as the underlying cause of death (eTable 4 in Supplement).