Sharing needles is the most common way people contract hepatitis C because the virus is transmitted via infected blood when a contaminated object is jabbed through the skin, touching an open wound. The virus can survive outside the human body for up to three weeks. Although hepatitis C is highly contagious, it cannot be transmitted by touching, kissing or coughing. It's other modes of transmission, via sexual intercourse or from mother to child, are rare.
Before 1992 -- the year blood screening for hepatitis C became available -- blood transfusion was the leading mode of transmission in the United States. That's one reason that baby boomers, or people born from 1945-1965, are five times more likely to have hepatitis C, according to the CDC, which recommends universal screening for this group. Baby boomers still comprise about 75% of all infections in the United States, but an alarming number of new infections are cropping up in people younger than 30 who share needles and other non-sterile equipment to inject drugs.
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