Hepatitis C risk factors


 * Intravenous drug users (IVDU)
 * Blood transfusion before 1990
 * Current transfusion-associated risk: < 1/100,000
 * Comparative risks: Hepatitis B Virus (HBV) 1/63,000, HIV 1/493,000
 * Residual risk due to recently infected donors (10 week window)
 * Percutaneous exposures
 * Needle stick transmission: ~3% HCV, 30% HBV, 0.3% HIV
 * Lesser Risk Factors
 * High-risk sexual behavior
 * Low socioeconomic status (unclear mechanisms)
 * Sexual transmission inefficient
 * HIV coinfection increases sexual and maternal-fetal transmission
 * Risk Factors For Progression
 * Alcohol use
 * HIV or HBV coinfection
 * Older age at infection, male sex


 * Number of new infections per year has declined from an average of 240,000 in the 1980s to about 26,000 in 2004.
 * Most infections are due to illegal injection drug use.
 * Transfusion-associated cases occurred prior to blood donor screening; now occurs in less than one per 2 million transfused units of blood.
 * Estimated 4.1 million (1.6%) Americans have been infected with HCV, of whom 3.2 million are chronically infected.
 * The risk for perinatal HCV transmission is about 4%
 * If coinfected with HIV the risk for perinatal infection is about 19%