HCV is the most common, chronic bloodborne infection in the US. CDC (2001) estimates that five million people in the US are HCV antibody positive. Worldwide, an estimated 3% of the population is infected (Al-Saden & Wachs, 2004). Officially discovered in 1989, Hepatitis C (HCV) is of the genera hepaciviruses, which is one of three genera in the Fiaviviridae family (Al-Saden & Wachs, 2004). HCV is hepatotrophic; the liver is the reservoir for the virus (Al-Saden & Wachs, 2004). The virus causes an immune response in the liver, causing inflammation. Prolonged inflammation damages liver tissue, causing fibrosis (scarring). If the fibrosis is not lessened or stopped it continues to progress into cirrhosis. Cirrhosis can lead to liver failure (Al-Saden & Wachs, 2004).
The United States (US) spends more than $600 million a year on the healthcare costs associated with liver disease related to the hepatitis C virus (HCV) (Al-Saden & Wachs, 2004). In the US, 8,000 to 10,000 deaths are attributable to HCV yearly. HCV- associated end-stage liver disease is the most frequent indication for liver transplantation among adults (Al-Saden & Wachs, 2004).
Most people are not aware of their infection because they are not clinically ill, but are a source of transmission to others. Most HCV-infected people are aged 30–49 years. Therefore, the number of deaths attributable to HCV-related chronic liver disease could markedly increase during the next 10–20 years as this group of infected people reaches ages at which complications from chronic liver disease typically occur (CDC, 1998).
There is no HCV vaccine on the market for prevention of HCV infection. The main source of transmission of HCV is infected people. HCV is transmitted primarily through large or repeated direct percutaneous exposures to blood. More than 60 percent of HCV infections are acquired by this route (Taylor & Waters, 2004). Risk factors associated with transmission of HCV in the United include blood transfusion, injecting-drug use, employment in patient care or clinical laboratory work, exposure to a sex partner or household member who has had a history of hepatitis, exposure to multiple sex partners, and low socioeconomic level. These studies reported no association with military service or exposures resulting from medical, surgical, or dental procedures, tattooing, acupuncture, ear piercing, or foreign travel. If transmission from such exposures does occur, the frequency might be too low to detect (CDC, 1998).
Injecting drug use is the primary risk factor for acquiring HCV infection. Injecting-drug use currently accounts for most HCV transmission in the US (CDC, 1998). Reuse of a syringe or needle from an infected drug user provides a transmission source (Al-Saden & Wachs, 2004). Many people with chronic HCV may have acquired their infection 20-30 years ago as a result of limited or occasional illegal drug injecting.
Nosocomial transmission of HCV is possible if infection-control techniques or disinfection procedures are inadequate and contaminated equipment is shared among patients. Reports from other countries do document nosocomial HCV transmission, but such transmission rarely has been reported in the US, other than in chronic hemodialysis settings. Studies indicate that HCV transmission might occur among patients in a hemodialysis center because of incorrect implementation of infection-control practices (CDC, 1998).
The following are recommended, routine precautions for the care of all hemodialysis patients (CDC, 1998).
Clean and contaminated areas should be separated; (e.g., handling and storage of medications and hand washing should not be done in the same or an adjacent area to that where used equipment or blood samples are handled).
Currently, no recommendations exist to restrict professional activities of health-care workers with HCV infection. As recommended for all health-care workers, those who are HCV-positive should follow strict aseptic technique and standard precautions, including appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments (CDC, 1998).
Blood transfusion accounted for a substantial proportion of HCV infections acquired more than15 years ago. In 1994 routine testing of donated blood began. Since that time, the risk of transfusion-transmitted HCV is almost zero (Taylor & Waters, 2004).
Organ transplantation organs from a HCV infected donor can be a source of transmission. There is a window period that may allow for transmission, even if the source tests negative (Al-Saden & Wachs, 2004).
Healthcare, emergency medical (e.g., emergency medical technicians and paramedics), and public safety workers (e.g., fire-service, law-enforcement, and correctional facility personnel) who have exposure to blood in the workplace are at risk for being infected with bloodborne pathogens. However, HCV prevalence among healthcare workers is not higher than in the general population. It averages one to two percent (Al-Saden & Wachs, 2004).
HCV is not transmitted efficiently through occupational exposures to blood. One study found that a history of unintentional needle-stick injury was the only occupational risk factor independently associated with HCV infection (CDC, 1998). The average incidence of anti-HCV seroconversion after accidental percutaneous exposure from an HCV-positive source is 1.8% (range: 0%--7%) (CDC, 2001). Transmission rarely occurs from mucous membrane exposures to blood. Data for HCV suggest that environmental contamination with blood containing HCV is not a significant risk for transmission in the health-care setting (CDC, 2001).
Universal blood and body fluid precautions should always be practiced to reduce and possibly eliminate the risk of exposure (Taylor & Waters, 2004). Engineering controls should be implemented to prevent exposure to blood. Protocols should be in place for the reporting and follow-up of percutaneous or permucosal exposures to blood or body fluids.
There is no data in the U.S. that indicates that people with tattooing and body piercing alone are at increased risk of HCV infection. In other countries, HCV infection has been associated with folk medicine practices, tattooing, body piercing, and commercial barbering. In the US, case-control studies have reported no association between HCV infection and these types of exposures (CDC, 1998).
Sexual transmission is not considered an efficient mode of transmission. Sexual transmission occurs in less than five percent of HCV cases (Taylor & Waters, 2004). Increased chances for sexual transmission occur with vaginal or anal sex with an infected person without the use of a condom or other barrier (Al-Saden & Wachs, 2004). Transmission of HCV can occur through oral sex with an infected person in the presence of open wounds or abrasions (Al-Saden & Wachs, 2004):
Prevalence of HCV infection among male patients with a HCV positive female partner (seven percent) was no different than that among males with a negative female partner (eight percent). However, female patients with a HCV positive partner were almost fourfold more likely to have HCV infection than females with a negative male partner (ten percent versus three percent respectively). These data indicate that, similar to other bloodborne viruses, sexual transmission of HCV from males to females is more efficient than from females to males (CDC, 1998).
Among people with high-risk sexual practices who deny a history of injecting-drug use, the prevalence of anti-HCV averages six percent. Unacknowledged percutaneous risk factors, like illegal injecting-drug use, might contribute to increased risk for HCV infection among people with high-risk sexual practices (CDC, 1998).
Perinatal transmission is not considered an efficient mode of transmission, less than 4.5 percent, so pregnancy is not contraindicated for women infected with HCV (Taylor & Waters, 2004), (Al-Saden & Wachs, 2004).
Data regarding the relationship between delivery mode and HCV transmission are limited. What is available indicates no difference in infection rates between infants delivered vaginally compared with cesarean-delivered infants. The transmission of HCV infection through breast milk has not been documented. Although serum anti-HCV antibody and HCV RNA have been detected in colostrums, HCV is not known to be transmitted to infants through breastfeeding (Taylor & Waters, 2004). In the studies that have evaluated breastfeeding in infants born to HCV-infected women, the average rate of infection was 4% in both breastfed and bottle-fed infants (CDC, 1998). Breastfeeding is not contraindicated (Al-Saden & Wachs, 2004).
Families sharing razors, toothbrushes, washcloths, and nail clippers are potential sources of transmission. Non-sexual household contacts have HCV prevalence rates of approximately one half percent to 13 percent (Al-Saden & Wachs, 2004).
The HCV is diagnosed with a positive HCV antibody test (Al-Saden & Wachs, 2004). Diagnosis of HCV is usually accidental because people with acute HCV infection typically are either asymptomatic or have a mild clinical illness. 60-70 percent of people with an acute infection are asymptomatic (Al-Saden & Wachs, 2004). Frequently, chronic HCV is not recognized until asymptomatic individuals are identified as HCV-positive during blood donor screening, or elevated ALT levels are detected during routine physical examinations.
Symptoms of acute HCV only occur in 30% of the cases and are similar to the other acute hepatitis infections. 20%-30% might have jaundice; and 10%-20% might have non-specific symptoms (CDC, 1998). Symptoms include the following (CDC, 2004):
The course of chronic liver disease is usually insidious, progressing at a slow rate without symptoms or physical signs in the majority of patients during the first two or more decades after infection. The course of acute hepatitis C is variable. Elevations in serum ALT levels, often in a fluctuating pattern, are its most characteristic feature. Normalization of ALT levels might occur and suggests full recovery, but this is frequently followed by ALT elevations that indicate progression to chronic disease.
15% to 25% of people with HCV resolve the infection on their own (Al-Saden & Wachs, 2004). Approximately 75% develop chronic infection, and 75% of those with chronic infection develop mild to moderate liver damage and have a normal life expectancy. 15% to 20% of people with chronic infection develop complications or cirrhosis leading to liver transplant (Al-Saden & Wachs, 2004). 1% to 5% of individuals develop hepatocellular carcinoma (Al-Saden & Wachs, 2004).
Factors predicting severity of liver disease have not been well defined. Recent data indicate that increased alcohol intake, being aged older than 40 at the time of infection, and being male are associated with more severe liver disease (CDC, 1998).
Testing should be offered routinely to the people most likely to be infected with HCV. Appropriate counseling and medical follow-up should accompany testing. The determination of high risk individuals to recommend for routine testing is based on various considerations, including a known epidemiologic relationship between a risk factor and acquiring HCV infection, prevalence of risk behavior or characteristic in the population, prevalence of infection among those with a risk behavior or characteristic, and the need for people with a recognized exposure to be evaluated for infection.
Recommendations for Testing Based on Risk (CDC, 2004).
Risk of Infection
Injecting drug users
Recipients of clotting factors made before 1987
Recipients of blood and/or solid organs before 1992
People with undiagnosed liver problems
Infants born to infected mothers
After 12-18 mos. old
Healthcare/public safety workers
Only after known exposure
People having sex with multiple partners
People having sex with an infected steady partner
As part of a complete medical history for all patients, it is important to obtain a history of high-risk exposures associated with HCV and other bloodborne pathogens. Such a history can be used to identify asymptomatic people who should be offered testing for HCV infection. Routine testing is currently recommended only for people who belong to groups with a known high prevalence of infection.
The average time period from exposure to symptom onset is 6-7 weeks. The average time period from exposure to seroconversion is 8-9 weeks. Anti-HCV can be detected in 80% of patients within 15 weeks after exposure, in greater than 90% within 5 months after exposure, and in greater than 97% by 6 months after exposure (CDC, 1998).
If a person’s exposure was in the past, people who test negative for HCV should be reassured. People whose HCV test results are indeterminate should be advised that the result is inconclusive, and they should receive appropriate follow-up testing or referral for further testing. People who test positive should be provided with information regarding the need for preventing further harm to their liver; reducing risks for transmitting HCV to others; and medical evaluation for chronic liver disease and possible treatment (CDC, 1998).
Antiviral therapy is recommended for patients with chronic hepatitis C who are at greatest risk for progression to cirrhosis. These people include anti-HCV-positive patients with persistently elevated ALT levels, detectable HCV RNA, and a liver biopsy that indicates either portal or bridging fibrosis or at least moderate degrees of inflammation and necrosis (CDC, 1998).
In patients with less severe histologic changes, indications for treatment are less clear, and careful clinical follow-up might be an acceptable alternative to treatment with antiviral therapy (e.g., interferon) because progression to cirrhosis is likely to be slow, if it occurs at all. Similarly, patients with compensated cirrhosis (without jaundice, ascites, variceal hemorrhage, or encephalopathy) might not benefit from interferon therapy. Careful assessment should be made, and the risks and benefits of therapy should be thoroughly discussed with the patient (CDC, 1998).
Patients with persistently normal ALT values should not be treated outside of clinical trials, since treatment might actually induce liver enzyme abnormalities. Patients with advanced cirrhosis who might be at risk for decompensation with therapy and pregnant women also should not be treated (CDC, 1998).
Interferon and ribavirin are two drugs licensed for the treatment of persons with chronic hepatitis C. Interferon can be taken alone or in combination with ribavirin. Combination therapy, using pegylated interferon and ribavirin, is currently the treatment of choice. Combination therapy can get rid of the virus in up to five out of ten persons for genotype 1 and in up to eight out of ten persons for genotype 2 and 3 (CDC, 2004)
Available Antiviral Medications (Al-Saden & Wachs, 2004)
Common side effects of ribavirin include (Al-Saden & Wachs, 2004):
Most patients receiving interferon experience flu-like symptoms early in treatment, but these symptoms diminish with continued treatment. Other common side effects of alfa interferons, regardless of whether or not pegylated are (Al-Saden & Wachs, 2004):
Immune globulin (IG) and antiviral agents are not recommended for postexposure prophylaxis (PEP) of HCV. Data regarding the prevention of HCV infection with IG indicate that IG is not effective for postexposure prophylaxis of hepatitis C. There has been no assessment of postexposure use of antiviral agents (e.g., interferon) to prevent HCV infection. The mechanisms of the effect of interferon in treating hepatitis C are poorly understood, and an established infection might need to be present for interferon to be effective. Interferon is not FDA-approved for this PEP (CDC, 2001).
There are no recommendations of PEP for HCV. Recommendations for postexposure management are intended to achieve early identification of chronic disease and, if present, referral for evaluation of treatment options.
Institutions should establish policies and procedures for HCV testing of people after percutaneous or permucosal exposures to blood. The conversion rate for post-needlestick exposure is 1.8% (0% to 7% range) (Al-Saden & Wachs, 2004). Healthcare professionals who provide care to people exposed to HCV in the occupational setting should be knowledgeable regarding the risk for HCV infection and appropriate counseling, testing, and medical follow-up.
Postexposure follow-up of healthcare, emergency medical and public safety workers for hepatitis C virus (HCV) infection (CDC, 1998)
Centers for Disease Control and Prevention (1998). Hepatitis C: What Clinicians and Other Health Professionals Need to Know, MMWR. 47 (19). Retrieved May 17, 2004 from http://www.cdc.gov/ mmwrhtml.
Centers for Disease Control and Prevention. (2001). Updated U.S. public health service guidelines for the management of occupational exposures to HBV, HCV, and HIV and recommendations for postexposure prophylaxis. MMWR 50(11) 1-42. Retrieved May 17, 2004 from http://www.cdc.gov/mmwr/preview/mmwrhtml/rr5011a1.htm
Al-Saden, P. & Wachs, J. (2004). Hepatitis C: An update for occupational health nurses. AAOHN Journal, 52(5), 210-219.
Centers for Disease Control and Prevention. (2004). Viral Hepatitis C. National Center for Infectious Disease. Retrieved May 17, 2004 from http://www.cdc.gov/ncidod/diseases/hepatitis/c/fact.htm.
Taylor, C. & Waters, K. (2004). Hepatitis C: A public health response in Kansas. Kansas Nurse. 79(4), 8-10.
Ward, R., Kugelmas, M. & Libsch, K. (2004). Management of Hepatitis C: Evaluating suitability for drug therapy. American Family Physician. 69(6). 1429-1437.