Transmission and Symptoms
How is HCV transmitted?
HCV is transmitted primarily through large or repeated percutaneous (i.e., passage through the skin) exposures to infectious blood, such as
•Injection drug use (currently the most common means of HCV transmission in the United States)
•Receipt of donated blood, blood products, and organs (once a common means of transmission but now rare in the United States since blood screening became available in 1992)
•Needlestick injuries in health care settings
•Birth to an HCV-infected mother
HCV can also be spread infrequently through
•Sex with an HCV-infected person (an inefficient means of transmission)
•Sharing personal items contaminated with infectious blood, such as razors or toothbrushes (also inefficient vectors of transmission)
•Other health care procedures that involve invasive procedures, such as injections (usually recognized in the context of outbreaks)
What is the prevalence of HCV infection among injection drug users (IDUs)?
The most recent surveys of active IDUs indicate that approximately one third of young (aged 18–30 years) IDUs are HCV-infected. Older and former IDUs typically have a much higher prevalence (approximately 70%–90%) of HCV infection, reflecting the increased risk of continued injection drug use. The high HCV prevalence among former IDUs is largely attributable to needle sharing during the 1970s and 1980s, before the risks of bloodborne viruses were widely known and before educational initiatives were implemented.