Hepatitis C Test Recommendations

Hepatitis C virus (HCV) infection is the most common chronic blood-borne infection in the United States. HCV persists as a chronic infection in 75 to 85% of individuals. Approximately 20% of infected persons will progress to cirrhosis within 20 years and up to 5% will die from HCV-related liver disease. Today, HCV infection is the leading indication for liver transplantation. Since many people can live with HCV for decades without developing symptoms, testing is critical. Highly effective medications are now available that can cure HCV infection. 

In 1998, the CDC recommended HCV testing for individuals at high risk for HCV transmission, including those who had injected drugs, been hemodialysed, transfused or transplanted before July 1992, or received clotting factor concentrates produced before 1987. Screening also was recommended for persons with occupational sharps exposures, children born to HCV-infected mothers and individuals with persistently elevated ALT levels and individuals infected with HIV. Unfortunately, this risk-based testing strategy had limited success, as evidenced by the substantial number of HCV-infected persons who remain unaware of their infection.

A recent analysis of NHANES data determined that the prevalence of HCV antibody among persons in the 1945–1965 birth cohort was 3.25%, compared to 1.0 – 1.5% in the general population. People within this age cohort account for approximately three fourths of all chronic HCV infections.  

In 2012, CDC published new birth-year based recommendations that target the baby boomer generation (MMWR August 17, 2012 / 61:1-18). These birth-year-based recommendations are intended to augment, not replace, the 1998 HCV testing guidelines. In addition to testing adults of all ages at risk, CDC now recommends that all adults born during 1945 to1965 should be tested one-time with an HCV antibody test (anti-HCV).  

CDC recommends testing the following individuals for HCV infection:

• Adults born from 1945 through 1965 should be tested at least once in their lifetime and more frequently if they are at ongoing risk 
• Persons who currently or previously inject drugs
• Patients who have HIV infection
• Patients with persistently abnormal alanine aminotransferase (ALT) levels
• Patients treated with clotting factor concentrates produced before 1987
• Patients who have ever received long-term hemodialysis
• Patients who were recipients of either blood transfusions or organ transplants before July 1992, or who were notified their donor later tested positive for HCV
• Children born to HCV-positive women
• Healthcare, emergency medical, and public safety workers with exposure to HCV-positive blood through needle sticks, sharps, or mucosal exposures

CDC also suggests that HCV testing may benefit:

• Recipients of transplanted tissues
• Persons who inject drugs
• Intranasal cocaine and other non-injecting illegal drug users
• Persons with a history of tattooing or body piercing
• Persons with a history of multiple sex partners or sexually transmitted infections
• Long-term steady sex partners of HCV-positive persons
• Persons who engage in high-risk sexual activity and with history of sexually transmitted infections

The initial test should be an immunoassay for HCV antibody. An immunocompetent person without risk factors who tests anti-HCV negative is not HCV-infected and does not require additional testing. Repeat testing should be considered for persons with ongoing risk behaviors. 

Individuals with reactive test results should be confirmed. A person whose anti-HCV test is reactive should be tested with quantitative real-time PCR for HCV RNA to distinguish active from cleared infection. Patients, who have confirmed positive results for HCV infection, should then have their HCV genotype determined. If an individual has HCV genotype 1a, they should be further tested for NS5a drug resistance. 

All patients with chronic HCV infection should be tested for evidence of current or previous Hepatitis B (HBV) infection by measuring Hepatitis B surface antigen (HBsAg) and Hepatitis B core antibody (anti-HBc). This testing should be completed before initiating HCV treatment because HBV may be reactivated. 

Reference:

CDC Testing Recommendations for Hepatitis C Virus Infection: http://www.cdc.gov/hepatitis/hcv/guidelinesc.htm