Six viruses, namely hepatitis A, B, C, D, E, and G mainly target the liver and cause inflammation, or hepatitis, as their primary clinical manifestation. Of these, chronic damage from Hepatitis C is the primary cause for end stage liver disease that needs liver transplantation.
Hepatitis C virus (HCV) is a double-shelled, single-stranded RNA virus that is detectable in blood during an acute or chronic infection. HCV replicates in the liver cells where white blood cells called lymphocytes recognize these infected cells and initiate an immune response to control the virus. Cells then produce proteins called cytokines that mediate this immune response and destroy liver cells, replacing them with fibrosis and later, cirrhosis, liver failure, and cancer.
HCV is contagious. It is spread through contact with an infected blood such as sharing needles or equipment to inject drugs, blood transfusions or organ transplants, or blood contamination in medical settings. Other potential sources of infection may include having multiple sexual partners, tattooing, body piercing, and maternal-fetal transmission. In the United States alone, it is estimated that 3.2 million people have chronic hepatitis C and most are not aware of their infection because symptoms can be very mild in the acute phase, and may include fever, joint pains, nausea, vomiting and loss of appetite. In fact, they can be asymptomatic for years. Usually when symptoms such as abdominal pain, dark urine, grey-colored stools, and jaundice appear, they are often advanced signs of the disease and call for hospitalization.
About 15%- 25% of people "clear" the virus without treatment while 75% - 85% of people who contract the virus develop a lifelong or chronic infection of which male gender, use of alcohol, and onset of infection have been identified to affect the course of the disease. Abnormal hepatic transaminase levels on routine testing prompts specific testing for hepatitis C. Once screening for hepatitis C antibodies is positive, other tests are conducted to determine if it is chronic or has been cleared.
Acute HCV is uncommonly diagnosed, but studies suggest that early treatment with interferon-based therapy decreases the risk of progression to chronic disease.
For patients with chronic HCV, the current recommended therapy is the combination of interferon alfa and ribavirin over many months. The goal is to eliminate the virus and control symptoms, improve liver function, and prevent complications of progressive liver disease including cirrhosis, liver failure, and hepatic carcinoma.
Abstinence from alcohol is also essential to the efficacy of therapy. People with chronic hepatitis C should regularly see their physicians and consult them before taking new medications or herbal supplements as they can potentially cause more liver damage. Likewise, there is no current vaccine to prevent hepatitis C.
Polygon Medical Animation illustrates in the following video the initial stages of HCV replication where the HCV virus enters a Hepatocyte cell of the liver. Once entered, the viral RNA is then released.
1 Department of Health & Human Resources, Center for Disease Control and Prevention, Division of Viral Hepatitis, June 2010
2 Hepatitis C, Cleveland Clinic, Center for Continuing Education, Medical Publication, 2012