Screening for hepatitis C virus (HCV) infection in persons at high risk for infection has been recommended by the United States Preventive Services Task Force (USPSTF). One-time screening for all adults born between 1945 and 1965 also was recommended.
The USPSTF recommendations are being reported in an article in the June 25 issue of Annals of Internal Medicine.
HCV, which can cause inflammation, permanent liver damage, and cancer, infects up to 3.9 million persons in the United States, according to the task force. Past or current injection drug use is the most significant risk factor, and receiving a blood transfusion before 1992 is an established one. Other risk factors include chronic hemodialysis; being born to an HCV-infected mother; incarceration; intranasal drug use; getting an unregulated tattoo; and other percutaneous exposures, such as being a health care worker and having surgery before the implementation of universal precautions.
HCV infection is most prevalent among persons born from 1945 through 1965, the task force noted. Many being unaware that they are infected becomes problematic because HCV progresses slowly and the risk of serious complications increases as time passes.
A risk-based approach may miss detection of a substantial proportion of HCV-infected persons in the birth cohort because patient disclosure and knowledge about previous risk status may be lacking, the task force found. One-time screening for HCV infection in the birth cohort may identify infected patients at an earlier, more treatable stage of disease.
The USPSTF found evidence to indicate the following:
• that anti-HCV antibody testing followed by confirmatory polymerase chain reaction testing accurately detects chronic HCV infection.
• that various noninvasive tests have good to very good accuracy in making a diagnosis of fibrosis or cirrhosis.
• that antiviral regimens result in sustained virologic response and improved clinical outcomes (even though they found no direct evidence on the benefit of screening for HCV infection in asymptomatic adults in reducing morbidity and mortality).
The USPSTF found inadequate evidence that counseling or immunization of patients with HCV infection against other infections improves health outcomes, reduces transmission of HCV, or changes high-risk behaviors; that knowledge of positive status for HCV infection reduces high-risk behaviors; or that labor management and breast-feeding strategies in HCV-positive women are effective at reducing risk for mother-to-child transmission.
The USPSTF concluded that screening for populations at high risk for infection and one-time screening in all adults in the United States born between 1945 and 1965 are of moderate benefit.
The USPSTF found limited evidence on the potential harms of screening for HCV, including anxiety, patient labeling, and feelings of stigmatization, and adequate evidence on the harms associated with the diagnostic evaluation used to guide treatment decisions, liver biopsy—bleeding, infection, and severe pain.
The USPSTF also found adequate evidence that antiviral therapy regimens are associated with a high rate of harms, such as fatigue, headache, flu-like symptoms, hematologic events, and rash, but that these harms of treatment are small.
This USPSTF recommendation is an update to a previous one. In 2004, the task force recommended against routine screening for HCV infection in asymptomatic adults who are not at increased risk for infection and found insufficient evidence to recommend for or against routine HCV screening for adults at high risk for infection.
To inform an update, researchers studied published evidence and focused on research gaps identified in the previous review. They found adequate evidence to indicate that the antiviral regimens used as treatment for patients with HCV infection result in improved clinical outcomes and that targeted screening misses up to two-thirds of infected patients.
In an accompanying editorial, the authors wrote that the task force’s expanded screening recommendations are especially important in light of the highly effective treatment that is now available for patients with HCV infection. They noted that antiviral agents can elicit a sustained virologic response (virologic clearance or cure) in up to 79% of patients when administered with peginterferon and ribavirin and that the benefits of HCV treatment are expected to increase.
An estimated 45% to 85% of persons with chronic HCV infection are unaware they are infected and thus do not receive needed care and treatment, the authors pointed out. In the absence of interventions, about 1 million persons infected with HCV will die of HCV-related disease, according to CDC estimates.
When HCV testing is accompanied by appropriate care and treatment, they stated, it can reduce risk by 70% for hepatocellular carcinoma and by 50% for all-cause mortality.
Screening both persons at risk and the birth cohort will help identify millions of Americans who previously were unaware of their infection status and thus help prevent liver disease and deaths attributable to chronic HCV infections, they concluded.