Mary D. Nettleman, MD, MS, MACP is the Chair of the Department of Medicine at Michigan State University. She is a graduate of Vanderbilt Medical School, and completed her residency in Internal Medicine and a fellowship in Infectious Diseases at Indiana University.
Hepatitis C is contagious. Transmission occurs mainly by contact with
Sharing of contaminated needles among IV drug users is the most common mode
of transmission. Using a needle to inject recreational drugs, even once several
years ago, is a risk factor for hepatitis C. Approximately one-third of young persons who use illicit, injectable drugs have hepatitis C. Older users
have a higher risk of disease (70% to 90% infected), especially if they injected
in the 1970s and 1980s.
In 1992, a test became available for checking blood for HCV. Blood and
blood products are now tested to ensure that they are not contaminated. As a
result, cases of hepatitis C related to transfusion, hemodialysis, or
transplantation have dropped to almost zero. Transfusion of blood or blood
products before 1992 is a risk factor for hepatitis C.
Less common causes of HCV transmission include the following:
From mother to infant at the time of childbirth
Through sexual intercourse with an infected person: Having multiple sex
partners is a risk factor.
Needle sticks with HCV-contaminated blood: This is mostly seen in health
care workers. The risk of developing HCV infection after a needle stick is about
1.8% (range 0%-10%). Very rarely, a blood splash to the eye of a worker has
transmitted hepatitis C.
Procedures done with equipment, such as an endoscope, that has not been
properly cleaned between patients. Some cases have also been traced to the reuse
of syringes that were contaminated with small amounts of blood from an infected
You cannot get hepatitis C by living with, being near, or touching someone
with the disease. You can get the disease by sharing items contaminated with
blood such as a razor, toothbrush, or nail clippers.
The source of transmission is unknown in about 30% of people with chronic