Confirmatory testing of hepatitis C virus-positiveenzymeimmunoassay results in limited-resource countries:should it be attempted?

摘要

Hepatitis C virus (HCV) infections are ubiquitous. It is estimated that at least 170 million people worldwide and an estimated 4 million persons in the United States are infected with HCV.Although the annual incidence of HCV appears to have declined in the United States in the past decade toapproximately 38,000 new cases,45 the incidence is increasing in several countries in Eastern Europe, Eurasia, and South Asia, especially in populations experiencing significant epidemics of illicit injection drug use.1 Most persons with acute or chronic HCV infections are asymptomatic and healthy; only about 20 percent of acute infections result in clinical hepatitis. Therefore, HCV infections among healthy blood donors, whether they are paid, replacement, or volunteer donors, are not uncommon. In the United States, Western Europe, and other high- or middle-income countries, blood samples from donors that are repeatedly reactive on enzyme immunoassay (EIA) screening are routinely evaluated with additional supplemental tests to determine which are true- and which are false-positive. The majority of repeat-reactive HCV EIA tests among blood donors in the United States are not confirmed by recombinant immunoblot assay (RIBA) or nucleic acid amplification testing (NAT).A study of 33.2 million donations collected by the American Red Cross and America's Blood Centers between 1999 and 2003 found that only 49.3 percent of 47,041 HCV EIA#