Follow-up tests to confirm HCV infection often not performed
HealthDay News -- Among Americans who test positive for hepatitic C virus infection (HCV) approximately half do not return for the second test necessary to confirm or refute the diagnosis, according to the CDC.
Surveillance data from two major cities and six states during a seven-year period indicate that 49.2% of 217,755 newly reported HCV patients underwent only the first test for antibodies to the virus, Deborah Holtzman, PhD, of the CDC's Division of Viral Hepatitis and colleagues wrote in Morbidity and Mortality Weekly Report.
Without the second test for HCV RNA, it is unclear whether patients with positive antibody tests have real evidence of infection, have false-positive test results or have leftover antibodies from a cleared infection, the researchers noted. These data suggest that "testing and reporting must improve" in order to detect all persons with current HCV infection.
"In an era of continued HCV transmission and expanding options for curative antiviral therapies, surveillance that identifies current HCV infection can help assess the need for services and link persons with infection to appropriate care and treatment," Holtzman and colleagues wrote.
Furthermore, initial results from clinical trials of investigational "direct-acting" HCV therapies are promising, suggesting that fast-acting therapies that rule out the need for poorly tolerated interferons are on the horizon.
The Vital Signs surveillance data results, coupled with earlier estimates that 3 million Americans have HCV -- the majority of whom do not know about their infection status -- have prompted the CDC to issue updated HCV testing guidance for clinicians and laboratory workers.
In the first HCV guideline update since 2003, the CDC is now recommending all people who have an antibody-positive HCV test receive the second, confirmatory HCV RNA test.
"Monitoring current HCV infection in states and localities can help gauge what interventions and services are needed to identify persons with HCV infection and effectively link them to appropriate care and treatment," the CDC wrote.
Although some people with HCV will clear the infection on their own, approximately 80% do not. Without treatment these people may develop liver disease, cirrhosis and cancer, CDC Director Tom Frieden, MD, said during a press briefing.
Patients who are aware of their infection status can make decisions to seek treatment and lifestyle choices to avoid further liver damage, and can get vaccinated against hepatitis B.
Surveillance data revealed that Baby Boomers -- those born between 1945 and 1965 -- represented the largest proportion of patients with positive HCV tests, representing 67.2% of those who underwent both antibody and RNA testing, and 58.5% of those who underwent only the first test.
Of those newly reported cases for which mortality data were available, 3.4% died, with deaths more likely among those aged 50 to 59 years. Across all sites, the annual rate of individuals with newly reported HCV infection was 84.7 per 100,000 people.
"To help identify persons with current HCV infection, public health and clinical care providers can offer HCV antibody testing to persons born during 1945–1965, in addition to those with other HCV risk factors, and test for HCV RNA those persons who test positive for HCV antibody," the researchers recommended.
They warned the study findings are limited to the eight surveillance sites, and may not be generalizable to other cities and states. The sites included San Francisco and New York City, as well as Colorado, Connecticut, Minnesota, New Mexico, New York State and Oregon.
- Centers for Disease Control and Prevention. "Vital signs: Evaluation of hepatitis C virus infection testing and reporting -- eight U.S. sites, 2005–2011." MMWR. 2013; 62:1-5.
- Centers for Disease Control and Prevention. "Testing for HCV infection: An update of guidance for clinicians and laboratorians." MMWR. 2013; 62:1-4.