Vital Signs

Newly Reported Acute and Chronic Hepatitis C Cases — United States, 2009–2018

A. Blythe Ryerson, PhD; Sarah Schillie, MD; Laurie K. Barker, MSPH; Benjamin A. Kupronis, MPH; Carolyn Wester, MD

Disclosures

Morbidity and Mortality Weekly Report. 2020;69(14):399-404. 

In This Article

Results

During 2018, a total of 3,621 cases of acute hepatitis C were reported, representing an estimated 50,300 cases (95% CI = 39,800–171,600), after adjusting for underascertainment and underreporting. During 2009–2018, the number of reported acute hepatitis C cases per 100,000 population increased threefold, from 0.3 in 2009 to 1.2 in 2018. During 2018, the highest rate of reported acute hepatitis C cases was in persons aged 20–29 years (3.1 per 100,000), followed by persons aged 30–39 years (2.6), 40–49 years (1.3), 50–59 years (0.9) and ≥60 years (0.4); the lowest rate (0.1) was in persons aged <20 years (Figure 1). This age pattern was consistent throughout 2009–2018, but the absolute increase in the annual case counts per 100,000 was highest for persons aged 20–39 years; among those aged 20–29 years, rates increased approximately 300%, from 0.7 in 2009 to 3.1 in 2018, and among those aged 30–39 years, rates increased approximately 400%, from 0.5 in 2009 to 2.6 in 2018.

Figure 1.

Rate* of reported acute hepatitis C cases,§ by year and age group — National Notifiable Diseases Surveillance System, United States, 2009–2018
*Cases per 100,000 U.S. population.
The states and jurisdictions reporting cases to CDC through the National Notifiable Diseases Surveillance System might vary by year (https://www.cdc.gov/hepatitis/statistics/2017surveillance/index.htm). During 2018, cases of acute hepatitis C were either not reportable by law, statute, or regulation; not reported; or otherwise unavailable to CDC from Alaska, Arizona, Delaware, District of Columbia, Hawaii, Iowa, Mississippi, and Rhode Island.
§Only confirmed, acute hepatitis C cases are included. Complete case definitions by year are available at https://wwwn.cdc.gov/nndss/conditions/hepatitis-c-acute/.

A total of 137,713 new chronic hepatitis C cases were reported during 2018. A larger percentage of these cases were among males (63.1%) than among females (36.9%) (Table). Among both males and females, a bimodal age distribution was observed, with the largest proportion of all newly reported chronic cases among persons aged 20–39 and 50–69 years (Figure 2). Baby boomers accounted for 36.3% of newly reported chronic hepatitis C cases in 2018, persons born during 1966–1980 (Generation X) accounted for 23.1%, and those born during 1981–1996 (millennials) accounted for 36.5%. (Table). Among 2015–2018 NHANES participants aged ≥20 years who were HCV RNA-positive, 60.6% (95% CI = 46.1%–73.9%) reported having been told that they had hepatitis C.

Figure 2.

Number of newly reported* chronic hepatitis C cases, by sex and age — National Notifiable Diseases Surveillance System, United States, 2018
*During 2018, cases of chronic hepatitis C were either not reportable by law, statute, or regulation; not reported; or otherwise unavailable to CDC from Alabama, Arizona, Arkansas, California, Delaware, District of Columbia, Hawaii, Indiana, Kentucky, Mississippi, Nevada, North Carolina, Rhode Island, and Texas.
Only confirmed, newly diagnosed, chronic hepatitis C cases with information regarding both sex and age are included. Complete case definition is available at https://wwwn.cdc.gov/nndss/conditions/hepatitis-c-chronic/case-definition/2016/.

Comments

3090D553-9492-4563-8681-AD288FA52ACE

processing....