Introduction
Hepatitis is caused by a number of things, including:
• alcohol abuse,
• medications,
• illegal drug use/abuse,
• chemical exposure, and
• viruses
Hepatitis C is caused by a virus. Currently, six viruses are known to cause hepatitis: A, B, C, D, E, and G. Hepatitis F is under investigation. Each of these viruses differs in terms of structure, signs of infection, virulence, and re-infection potential.
Why is Hepatitis C such a problem?
When Hepatitis C first enters the body, it stimulates an immune response, causing the body to make an antibody called anti-HCV (Hepatitis C virus). Then it mutates into a different shape – one that the body does not recognize. Over the course of many years, the virus changes multiple times; remaining, for the most part, hidden from the immune system.
Because HCV mutates again and again, the body cannot mount an adequate immune response – which means that HCV cannot be eradicated in most people. About 85% of those infected with HCV will develop a chronic infection. Researchers have not been able to develop a vaccine to prevent Hepatitis C infection because the viral mutation makes it like trying to hit a moving target.
The NIH estimates that about 20% of the people with chronic Hepatitis C will develop cirrhosis of the liver over at least 20-30 years. Cirrhosis is a serious condition that can lead to liver failure. Currently, Hepatitis C is the number one reason for liver transplants. In a smaller percentage (1-5%) of those with chronic HCV, hepatocellular carcinoma (HCC) will develop. In some parts of the world (i.e., Japan), the chance of developing HCC is much higher.
According to the CDC, an estimated 4.1 million (1.6%) Americans have been infected with HCV. There are, on average, 19,000 new infections per year.2
While the incidence of new infections has declined dramatically in the last ten years, the clinical effects of past infections are emerging now.
How is Hepatitis C transmitted?
The Hepatitis C virus is a blood-borne pathogen. Contact with the blood or body secretions of someone infected with Hepatitis C puts you at risk.
Injectable drug users are most at risk of contracting HCV. Even people who have only used injectable drugs once or twice may become infected. According to the NIDA, at least 60% of HCV infection in the United States is related to injection drug use, and 50-80% of all new injectable drug users become infected within 6-12 months.3
Drug use by nasal inhalation: Drugs that are "snorted" such as cocaine and crystal methamphetamine may carry a risk of Hepatitis C acquisition when straws are shared, through contact with trace amounts of mucus and blood.
Transfusion of blood products: Recipients of clotting factors made before 1987 are at a high risk of HCV infection and should receive testing to determine if they are infected. Those that have received blood products and/or solid organs before 1992 are at an intermediate risk and should also be tested. With current testing of blood products, the risk of acquiring HCV through a transfusion is exceedingly small (<1 per 2 million transfused units).
Improperly sterilized medical or dental equipment can harbor HCV. Use of appropriate sterilization techniques and proper disposal of used equipment can reduce the risk of exposure to HCV to virtually zero.
Sexual transmission of HCV is rare in monogamous, heterosexual relationships. The highest risk of transmission is associated with multiple sexual partners and with traumatic sex that results in blood exposure. Use of latex condoms correctly and every time may help prevent the spread of this and other sexually transmitted diseases.
Mother to child transmission of HCV only occurs among infants born to women who are HCV RNA positive at the time of delivery (transmission risk approximately 4 %). However, if the mother is both HCV and HIV positive at the time of delivery, the risk increases to about 19%.2
Hemodialysis patients are at risk of acquiring HCV. The annual incidence is currently reported at between 0.73-3%. A major risk factor for hemodialysis patients is the number of years on dialysis. The longer the patient is on dialysis, the more likely it is that they will acquire HCV. Prevalence rates for patients who have been on dialysis <5 years is around 12%, increasing to 37% in patients receiving dialysis ≥5years. Investigations of dialysis-related outbreaks of HCV suggest that transmission is most likely related to inadequate infection control practices.4
Health Care Workers are at risk of acquiring HCV through accidental needle sticks, sharps exposure, or a blood splash to the eye or an open wound. Universal precautions can significantly reduce the risk of exposure to HCV.
Other potential sources of transmission include tattoo or body piecing with unsterilized equipment or through sharing personal care items such as toothbrushes, nail clippers or razors with an infected individual.
Who should be tested for HCV?
• Anyone who has ever injected illegal drugs—even just once
• Those who are notified that they had received blood from a donor who later tested positive for hepatitis C
• Recipients of clotting factors made before 1987
• Hemodialysis patients
• Recipients of blood and/or solid organs prior to July, 1992
• People with undiagnosed liver problems
• Infants born to infected mothers (test at 12-18 months of age)
• Health care/public safety workers after a known exposure
How is Hepatitis C Treated?
If you are HCV positive:
• Be evaluated for liver disease
• Receive vaccinations for Hepatitis A and B which would radically worsen liver prognosis if contracted
• Do NOT use drugs or drink alcohol
• Receive combination therapy with pegylated interferon and ribavirin—duration of treatment will vary depending on which genotype of HCV is involved.
• Consider "triple therapy," if indicated. Some studies have shown higher success rates with the addition of the antiviral drug amantadine (Symmetrel®), especially for "nonresponders."5,6
References
1. Celebrities with Hepatitis C. (2003, Nov. 9). Kansas City Star website, retrieved 6/16/08: www.kansascity.com/living/ health/hepatitis/v-print/story/38570.html
2. Centers for Disease Control and Prevention website (March 6, 2008). Viral hepatitis C fact sheet, retrieved 5/28/2008: www.cdc.gov/NCIDOD/Diseases/hepatitis/c/fact.htm
3. Leshner, A. , National Institute on Drug Abuse website. (May, 2000). NIDA Community Drug Alert Bulletin—Hepatitis, Retrieved 5/28/2008. www.drugabuse.gov/ HepatitisAlert/HepatitisAlert.html
4. Alter, M. and Tokars, J. (April 27, 2001).Recommendations for Preventing Transmission of Infections Among Chronic Hemodialysis Patients. Centers for Disease Control website. Retrieved 6/18/2008: http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5005a1.htm
5. Smith et. al. (May 2002). Amantadine Therapy for Chronic Hepatitis C. (Online) PubMed website. Retrieved 6/18/2008:
http://www.pubmedcentral.nih.gov/articlerender.fcgi?artid=1492374
6. Wikipedia website (June 16, 2008). Hepatitis C. Retrieved 6/16/2008:
http://en.wikipedia.org/wiki/Hepatitis_C
Some of the material in this article was excerpted from the Hepatitis C homestudy offered by TCHP. The TCHP Education Consortium offers homestudy education on a variety of health care topics on their website at www.tchpeducation.com. Homestudies are available to read free of charge on their website. If contact hours are desired, the processing cost is $5 per contact hour.
