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.
Jay W. Marks, MD, is a board-certified internist and gastroenterologist. He graduated from Yale University School of Medicine and trained in internal medicine and gastroenterology at UCLA/Cedars-Sinai Medical Center in Los Angeles.
How does liver damage occur in hepatitis C infection?
The presence of HCV in the liver triggers the human
immune system, which leads to inflammation. Over time (usually decades),
prolonged inflammation may cause scarring. Extensive scarring in the liver is
called cirrhosis. When the
liver becomes cirrhotic, it fails to perform its normal functions, (liver failure), and this leads to serious complications and even
death. Cirrhotic livers also are more prone to become cancerous.
How is hepatitis C virus spread, is it contagious, and how can transmission be prevented?
HCV is spread (transmitted) most efficiently through
exposure to infected blood.
The most common route of transmission is
needles shared among users of illicit drugs.
Accidental needle-sticks in
health care workers also have transmitted the virus. The average risk of getting
HCV infection from a stick with a contaminated needle is 1.8% (range 0% to
1992, some people acquired the HCV infection from transfusions of blood or blood
products. Since 1992, all blood products have been screened for HCV, and cases of HCV
blood transfusion now are extremely rare.
HCV infection also can be passed from mother to unborn
child. Approximately 4 of every 100 infants born to HCV-infected mothers become
infected with the virus.
A small number of cases are transmitted through sexual
intercourse. The risk of transmission of HCV from an infected individual to a
non-infected spouse or sexual partner without the use of
condoms over a lifetime has
been estimated to be between 1% and 4%.
Finally, there have been some outbreaks of HCV
when instruments or exposed to blood have been re-used without appropriate cleaning
Transmission of HCV can be prevented in several ways.
Prevention programs have been aimed at avoiding needle sharing among drug addicts. Needle
exchange programs and educational interventions have reduced transmission of HCV
infection. However, the population of drug addicts is a difficult population to
reach, and rates of HCV remain high among addicts (30% of younger users).
healthcare workers, safe needle-usage techniques have been developed to reduce
accidental needle-sticks. Newer syringes have self-capping needle systems that
avoid the need to manually replace a cap after drawing blood and reduce the risk
There is no clear way to prevent transmission of the HCV from
mother to child.
Persons with multiple sexual partners should use barrier
precautions such as condoms to limit the risk of HCV as well as other
If one partner is infected, monogamous couples should consider the low risk
of transmission of HCV infection when deciding whether to use condoms during intercourse. Some
couples may decide to use them and some may not.
Screening tests for blood
products have almost eliminated the risk of transmission of HCV infection through transfusion,
estimated by the CDC to be less than one in
two million transfused blood products.
People with HCV infection should not share razors
or toothbrushes with others.
It is critical that physicians and clinics follow
manufacturer's directions for sterilizing/cleaning instruments and that
disposable instruments be discarded properly.
It is important to realize that HCV is not spread by casual contact. Thus,
shaking hands, kissing, and hugging are not behaviors that increase the risk of
transmission. There is no need to use special isolation procedures when dealing
with infected patients.