Professeur docteur oussama chaalane

Hepatitis C: The Silent Epidemic
Each year, a barrage of new and old threats to our health is thrust on the public by the mainstream media. In many cases, the widespread concern caused by these media salvos is disproportionate to the actual or potential harm associated with the news reports. As a result, we are sometimes distracted from diseases that clearly threaten our health. Among the more serious public health problems, hepatitis C remains overlooked. It is even referred to by many as "the silent epidemic."1
Consider that 4.5 million people in the United States are infected with hepatitis C; yet, 80% of these people have no signs or symptoms of the disease.2 Many people in the United States are more familiar with hepatitis A and B, 2 types of viral hepatitis that have been extensively studied and publicized through public health programs. However, hepatitis C is significantly different from these other 2 diseases. Hepatitis C is a deadlier disease, and because it is a relatively newer medical discovery, much less is known about the disease.3
It is important for radiologic technologists (RTs) to continuously learn and utilize current information regarding the hepatitis C virus, not only to help patients but also to protect themselves. RTs have been taught to utilize universal precautions when working with bodily secretions. These precautions have been in place for the past 20 years, corresponding to the AIDS epidemic. Wearing gloves and other protective articles must become a habit for healthcare professionals, rather than choice. In learning about hepatitis C, it becomes apparent that this critical choice could mean the difference between routine safety and a lifetime of chronic liver disease or worse. Therefore, it is important that healthcare personnel working with patients realize the risks involved when precautions are not taken to prevent hepatitis C infection.
In the following article, many aspects of hepatitis C will be discussed, with a focus on the severity, prevention, and treatment of the disease. The discussion will also include information that can be helpful in planning simple education awareness programs for healthcare professionals, patient groups with high-risk behaviors, and the general public. The discussion will begin with an overview of hepatitis and a detailed description of hepatitis C.
Hepatitis
Hepatitis is an inflammation or swelling of the liver that can develop from a variety of causes. These causes include viruses, alcohol, drugs (including prescription medications), poisons, autoimmune disease, and opportunistic infections such as Mycobacterium avium or Cytomegalovirus. Hepatitis can lead to cirrhosis, liver cancer, and liver failure, which can all be fatal (See Table 1 for more information on the liver).1,4-7 Presently, at least 6 different types of hepatitis virus have been identified: hepatitis A, B, C, D, E, and G. The majority of hepatitis cases are caused by hepatitis A, B, and C. In fact, some of the other varieties of hepatitis virus only exist in the presence of hepatitis A, B, or C.1,7
Hepatitis C is caused by exposure to the hepatitis C virus. Viruses are small micro-organisms that primarily consist of DNA or RNA. A virus works by attaching to a cell and inserting its genetic material into this cell. The virus causes the infected cell to manufacture more virus copies. Eventually, the infected cell dies, and the virus copies are released to infect multiple surrounding cells, which are eventually killed. This process leads to a state of disease characterized by tissue damage and tissue death. In many cases, this process can be fatal.1
Hepatitis A virus is found in the feces of persons with hepatitis A and is usually transmitted person-to-person by placing items in the mouth (usually food or water) that have been contaminated by virus-containing feces. Hepatitis A is a short-term infection, typically resolving within 6 months without serious health problems.8 According to the Centers for Disease Control and Prevention (CDC), there are approximately 150 000 new infections each year in the United States. There are 2 types of vaccines available in the United States for protection against hepatitis A.1 Both vaccines are made from inactivated whole virus and require 2 vaccinations for complete immunization.9,10
The hepatitis B virus is found in infected blood and other body fluids. It is predominantly transmitted through sexual contact. This disease is much more infectious and prevalent than HIV, with an estimated 1.2 million chronic carriers in the United States.11 Chronic carriers are those individuals who have had the virus in their system for more than 6 months. Without treatment, the risk of developing cirrhosis and liver cancer is greatly increased. Between 5% and 10% of newly infected people may develop chronic hepatitis or become carriers. A noninfectious recombinant vaccine is available to prevent hepatitis B and requires multiple vaccinations for complete immunization.12
Hepatitis C
Hepatitis C was initially known as "non-A, non-B hepatitis." Research later found that the hepatitis C virus was actually an entirely different type of virus, known as an RNA virus.13 The viruses that cause hepatitis A and B are DNA viruses.1 The hepatitis C virus, sometimes referred to as the "stealth virus," is unique because of its capacity to continuously mutate. This ability allows it to cleverly evade the body’s immune system. At present, there are 6 genotypes and more than 50 subtypes of the hepatitis C virus.3
What Makes Hepatitis C a Special Concern
Several attributes of hepatitis C make this disease a special public health concern. Whereas hepatitis A and B cause a brief, intense infection, hepatitis C causes chronic infection.1 In fact, 80% to 90% of people infected with the hepatitis C virus will have the disease for years, many of them for decades. It is the propensity of the virus to mutate that leads to high rates of chronic infection. When individuals become infected with the hepatitis C virus, the body begins the process of producing antibodies directed against the virus. However, by the time the antibodies are fully developed and ready to attack the original virus, the antibodies ultimately fail because the virus has already mutated to a new version. Because of this high mutation rate, chronic infection is able to develop in 55% to 85% of infected persons. This is significant because chronic liver disease will develop in 70% of chronically infected persons. In fact, hepatitis C virus is one of the leading known causes of liver disease in the United States and throughout the world.13
Chronic liver disease is currently the 10th leading cause of death among adults in the United States. Viral hepatitis plays a significant role in chronic liver disease because it is estimated that hepatitis C is responsible for 40% to 60% of chronic liver disease, whereas another 10% to 15% of chronic liver disease is caused by chronic hepatitis B.14 Of those persons infected with the hepatitis C virus, 1% to 5% are likely to die from chronic liver disease. Consequently, liver disease caused by hepatitis C infection is currently the main indication for liver transplantation in the United States.14
In addition to liver disease, a small percentage of patients suffer from liver cancer. Scientists have demonstrated a strong association between hepatitis C and liver cancer.3 Chronic hepatitis C virus infection can also have autoimmune, dermatologic, hematologic, neurologic, ocular, pulmonary, and renal disease manifestations.13 Because the virus is capable of continuously mutating, research to develop a vaccine is extremely difficult. At present, there is no vaccine to prevent hepatitis C. This is especially significant, given that hepatitis C is the most common, chronic, blood-borne viral infection in the United States.14
The Silent Epidemic
Hepatitis C has been referred to as the silent epidemic for many reasons. M
ost notably, only 20% of people with hepatitis C develop signs or symptoms of the disease (See Table 2 for list of symptoms).2 Moreover, chronic liver disease caused by hepatitis C typically progresses at a slow rate during the first 2 or more decades after infection, without signs or symptoms. Because most people infected with the disease are thought to have been infected within the past 15 to 20 years, the true burden of infection may not become apparent for many years.1
Due to the insidious nature of this disease, routine testing of individuals at high risk for infection is of paramount importance. Healthcare personnel are on the front line of the battle and should become familiar with the risk factors and risk groups associated with hepatitis C infection.14
Risk Factors and Risk Groups
The hepatitis C virus is transmitted primarily through percutaneous exposure to contaminated blood. Groups at highest risk for hepatitis C infection include low-income individuals, healthcare workers, military veterans, intravenous drug users, alcoholics, sexually active persons who have multiple partners, people in prisons, and homeless people.1 Risk factors for hepatitis C virus infection include the following:
• Injection and other illicit drug use — Approximately 60% of new hepatitis C infections are associated with injection drug use. In addition, intranasal cocaine use has also been associated with infection.13
• Transfusion and organ transplantation — In 1992, hepatitis C virus antibody testing began to make this route of transmission rare. However, recipients of blood transfusions and organ transplants before this date remain at considerable risk.13
• Correctional facility — Incidence rates (new infections) among prisoners are extremely high. Some prisons have reported rates between 80% and 100%.1
• Low-income groups — Inner-city hospitals have reported prevalence rates of approximately 20%.1
• Racial and ethnic groups — In the United States, the highest incidence rates (new infections) are among African Americans, followed by Native Americans, Hispanics, and Caucasians.1
• Hemodialysis — The prevalence of antibodies against the hepatitis C virus is approximately 8% among hemodialysis patients. Inadequate infection control practices are the likely cause of infection.13
• Healthcare workers — Needlestick injury has led to hepatitis C infection in 3% to 4% of workers having such an episode; hepatitis C transmission has also been reported as a result of blood splash to the conjunctiva.13 RTs work in a variety of settings with individuals from all walks of life. Handling bloody items could be a routine aspect of the job, especially in an emergency department. In addition, requirements for patient confidentiality may prevent RTs from having all the information regarding patient diagnosis. For these reasons, RTs must always assume patients are infectious and vigilantly follow universal precautions to protect themselves.
• Sexual activity — Sexual transmission reportedly occurs in the United States at a frequency of 2.7% among heterosexual couples in monogamous relationships.13
• Tattooing/body piercing — Contaminated equipment or supplies have been implicated in the transmission of the hepatitis C virus.13
• Mother/fetus transmission — The incidence of hepatitis C virus infection is 5% to 6% among infants born to women infected with the hepatitis C virus. However, the incidence is as high as 20% among children born to mothers coinfected with HIV and the hepatitis C virus.13
• Other — There is no evidence that casual contact causes hepatitis C infection. However, sharing household items that may be contaminated with blood should be avoided.13
Routine Hepatitis C Testing
Individuals at high risk of hepatitis C infection should be identified and provided appropriate testing and counseling. Table 3 contains guidelines for testing that are based on recommendations by the CDC.2 Testing is required to identify infected persons at risk for chronic liver disease and for identifying infected persons to prevent them from transmitting hepatitis C to others. Individuals who test positive for hepatitis C infection should receive a medical referral to evaluate the extent of any liver disease, counseling to facilitate antiretroviral treatment, and drug or alcohol abuse treatment, if appropriate. Additionally, immunizations against hepatitis A and B (people infected with hepatitis C virus can still become infected with hepatitis A or B virus), influenza, and pneumococcal virus should be considered. Individuals testing negative should also receive counseling to reduce risky behavior, facilitate drug or alcohol abuse treatment, and coordinate appropriate immunizations.14
Hepatitis C testing involves several different types of tests with a variety of purposes. Table 4 provides a brief overview of these tests.15 Although many tests have been recently developed to better assist clinicians with the diagnosis and treatment of hepatitis C, the first test was developed only 13 years ago, in 1993. Because of the recency of research developments on hepatitis C, a significant lag exists in the application of new knowledge and technology. In fact, a recent study has underscored this gap. Blood banks, most hospitals, and many private diagnostic laboratories have the capacity for testing for the hepatitis C antibody. However, a survey showed that less than 50% of state and local public health laboratories are able to perform any type of hepatitis C testing. This finding is yet another example of the challenges faced by public health officials.14
HIV or Hepatitis C Virus: Which is Worse?
HIV and hepatitis C virus represent 2 of the most significant public health challenges of our times. However, the public health threat from the hepatitis C epidemic continues to be grossly underestimated by a majority of people in the United States, particularly politicians and healthcare personnel. Hepatitis C is extremely deadly and is already an epidemic of unprecedented terms. For example, without rapid intervention to contain the spread of the disease, the death rate from hepatitis C will soon surpass that from AIDS.1 Hepatitis C infection is already 4 times more prevalent than HIV infection in the United States.16 The current prevalence of hepatitis C is estimated to be 4.5 million Americans.1 The worldwide prevalence is estimated to be 200 million, making hepatitis C one of the greatest public health threats faced in this century, and perhaps the next century.1
In addition to loss of life, hepatitis C is responsible for significant healthcare costs and economic losses from lost work.1 The CDC has estimated that each year, hepatitis C causes $600 million in medical expenses and work-loss costs as a result of acute and chronic liver disease.17 However, when calculating the total lifetime costs for the current 4.5 million Americans who are believed to be infected with hepatitis C virus, the cost is estimated to be as high as $9 billion/year.1
The hepatitis C and HIV viruses not only pose threats as individual infections, but public health experts have also discovered a deadly interaction between the 2 viruses. In fact, coinfection with hepatitis C, HIV, and/or hepatitis B is now recognized as a significant problem and is indicative of the need for integrating prevention strategies.14
Treatment of Hepatitis C
The current standard of therapy that is most effective for treatment of hepatitis C is a combination of α-interferon and ribavirin. This combination therapy provides sustained elimination of hepatitis C viral infection for more than 6 months in 30% to 40% of patients. Although significant side effects cause 10% to 20% of treated patients to stop treatment before completion of therapy, newer treatments that have entered the market are more tolerable and have fewer side effects.14 In addition, serious side effects do not occur in all patients.3
Although all patients with chronic hepatitis C are potential candidates fo
r antiretroviral therapy, treatment is recommended for patients with increased risk of developing cirrhosis. In some patient populations, treatment decisions should be made on an individual basis because the risks and benefits of therapy are less clear. Many patients with chronic hepatitis C have been ineligible for clinical trials because of injection drug use, alcohol abuse, or comorbid medical and neuropsychiatric conditions.3
Treatment of hepatitis C in African Americans has presented significant difficulties. Research has found that the current standard of therapy is not as effective in certain patients with the genotype 1 virus. Studies have shown that because this type of virus is more prevalent in African Americans, the percentage of African Americans who respond to treatment is less than Caucasians. However, it is important to remember that treatment is still equally effective in many African Americans. In addition, newer treatments are showing encouraging results and some clinical trials have been designed to test elevated doses of new drugs in African Americans.18
Past or current alcohol abuse has significant negative ramifications for all patients receiving antiviral or interferon treatment.14 Alcohol is an important cofactor in the progression of hepatitis C liver disease to cirrhosis and liver cancer.3 Abstinence from alcohol is recommended for all patients with hepatitis C infection.14
Protect Yourself and Others From Hepatitis C
Healthcare professionals should protect themselves from hepatitis C by taking the following proactive steps1:
• Always wear gloves when wiping up blood, handling personal items (eg, tissues and tampons), or touching other sources of contaminated blood.
• Immediately clean up spilled blood with a strong disinfectant and keep skin injuries bandaged.
• Do not share razors, toothbrushes, pierced earrings, or other personal items with anyone.
• Use condoms if you have multiple sex partners or have sex with infected persons.
• Properly sterilize needles or other sharp implements for drugs, ear piercing, manicuring, or tattooing.
• Avoid using blood products outside the United States and Europe because testing for hepatitis C is not standard in many non-Western countries.
• Do not prechew food for a baby.
• Do not share gum that has already been chewed.
Health Education and Public Awareness
Hepatitis C is also known as the silent epidemic because it remains relatively unknown to the general public and measures to prevent the disease are still only slowly becoming standard practice among healthcare personnel. A recent survey commissioned by the American Gastroenterological Association (AGA) found that there are significant misperceptions about the disease among many, including physicians, the general public, and patients with hepatitis C. For example, 20% of the general population and 15% of patients with hepatitis C incorrectly believe that a vaccine for the disease exists. Another surprising finding was that only 55% of primary care physicians in the survey routinely asked their patients about risk factors, and only 30% of these primary care physicians tested for hepatitis C as part of a routine checkup.16 Table 5 lists several myths that are currently hindering prevention and treatment of this disease.2,14,17,18
As indicated by the AGA survey, proper education of healthcare professionals remains an unmet need. Because hepatitis C was only recently identified in 1988, healthcare professionals are often unaware of current information concerning diagnosis, medical management, and prevention of this disease.14 Vigilant levels of awareness are needed among healthcare professionals to maximize the identification of individuals infected with the hepatitis C virus. To increase awareness, coordinated education and communication efforts must be directed at healthcare and public health professionals, people at risk for infection, and the general public.
Although patient education is not the primary job of an RT, they are likely to come in contact with an increasing number of infected patients, and it is important that they are prepared. RTs help provide physicians with important information for the diagnosis and treatment of hepatitis C. Although they may not play a direct role in diagnosis and treatment, RTs should be able to provide accurate information to patients or other interested individuals. By no means should an RT initiate a dialogue about a patient’s diagnosis or risk factors. However, in the event that the patient expresses a concern or question about the diagnosis or treatment of hepatitis C, RTs should be prepared to respond with accurate, informative information, and encourage patients to seek specific information from their physician.
Education of healthcare professionals requires further development of educational programs, creation and dissemination of materials to assist healthcare professionals in identifying persons at risk for hepatitis C infection, and periodic updates of guidelines for the diagnosis, treatment, and prevention of hepatitis C. In addition, educational messages must be developed and distributed in communities with high prevalence rates of hepatitis C infection. In many cases, creating public awareness in these communities requires the development of culturally sensitive materials that account for language and literacy barriers.14
Conclusions
Hepatitis C is indeed a silent epidemic. Without a preponderance of signs or symptoms among the millions of individuals infected with the hepatitis C virus, this silent epidemic is poised to grow without challenge. This is especially true, given the difficulties in developing an effective vaccine. However, scientists have made significant strides in the development of hepatitis C tests and treatments. In addition, public awareness is beginning to exert pressure on policy makers. More citizens are asking for budget increases to provide adequate testing, counseling, and programs for public awareness.
The hepatitis C battle will require efforts at the global, national, state, local, and individual levels. Many resources are available to help in the dissemination of information (Table 6). It is critical that healthcare professionals start getting more involved in the workplace and community so that hepatitis C no longer remains a silent epidemic.
References
1. Hepatitis C: An Epidemic for Everyone. C. Everett Koop Institute at Dartmouth Web site. Available at: http://www.epidemic.org/. Accessed August 30, 2006.
2. Hepatitis C Fact Sheet. Centers for Disease Control and Prevention Web site. Available at: http://www.cdc.gov/ncidod/diseases/hepatitis/c/fact.htm. Accessed August 28, 2006.
3. Management of Hepatitis C: National Institutes of Health Consensus Conference Statement June 10-12, 2002. National Institutes of Health Web site. Available at: http://consensus.nih.gov/2002/2002HepatitisC2002116html.htm. Accessed August 28, 2006.
4. The Body: A Complete HIV/AIDS Resource. Body Health Resources Corporation Web site. Available at: http://www.thebody.com/nmai/hepatitis.html. Accessed August 30, 2006.
5. Cincinnati Children’s Hospital Medical Center. Liver anatomy and function. Available at: http://www.cincinnatichildrens.org/svc/alpha/l/liver/liver-anatomy.htm. Accessed September 12, 2006.
6. Three Rivers Endoscopy Center gihealth.com e-Newsletter. Cirrhosis of the liver. Available at: http://www.gihealth.com/newsletter/34/cirrhosis.html. Accessed September 12, 2006.
7. The American Liver Foundation. Your liver treats you right. Available at: http://www.alfdc.org/learning/Your%20Liver%20Treats%20You%20Right.pdf. Accessed September 12, 2006.
8. Hepatitis A Fact Sheet. Centers for Disease Control and Prevention Web site. Available at: http://www.cdc.gov/hepatitis. Accessed August 30, 2006.
9. VAQTA (Hepatitis A Vaccine, Inactivated) Prescribing Information. Whitehouse Station, NJ: Merck & Co., Inc.; 2006.
10. HAVRIX (Hepatitis A Vaccine, Inactivated) Prescribing Information. Research Triangle Park, NC: GlaxoSmithKline; 2005.
11. Hepatitis B Fact Sheet. Centers for Disease Control and Prevention Web site. Available at: http://www.cdc.gov/ncidod/diseases/hepatitis/b/fact.htm. Accessed August 30, 2006.
12. ENGERIX-B [Hepatitis B Vaccine (Recombinant)] Prescribing Information. Research Triangle Park, NC: GlaxoSmithKline; 2005.
13. Lo Re V, 3rd, Kostman JR. Management of chronic hepatitis C. Postgrad Med J. 2005;81:376-382.
14. National Hepatitis C Prevention Strategy. Centers for Disease Control and Prevention Web site. Available at: http://www.cdc.gov/ncidod/diseases/hepatitis/c/plan/index.htm. Accessed August 29, 2006.
15. Hepatitis C: Lab Tests Online. American Association for Clinical Chemistry Web site. Available at: http://www.labtestsonline.org/understanding/analytes/hepatitis_c/test.html. Accessed August 30, 2006.
16. Stigma of Hepatitis C and Lack of Awareness Stops Americans from Getting Tested and Treated. American Gastroenterological Association Web site. Available at: http://www.gastro.org/wmspage.cfm?parm1=420. Accessed August 30, 2006.
17. Recommendations for Prevention and Control of Hepatitis C Virus (HCV) Infection and HCV-Related Chronic Disease: MMWR 47 (RR19); 1-39. Centers for Disease Control and Prevention Web site. Available at: http://www.cdc.gov/mmwr/preview/mmwrhtml/00055154.htm. Accessed August 30, 2006.
18. Daniel S. Chronic hepatitis C treatment patterns in African-American patients: an update. Am J Gastroenterol. 2005;100:716-722.

 

 

 

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