Hepatitis C

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).
 

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):

• jaundice
• fatigue
• dark urine
• abdominal pain
• loss of appetite
• nausea

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.

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).

• To protect their liver from further harm, HCV-positive people should be advised to
  • Not drink alcohol;
  • Not start any new medicines, including over-the-counter and herbal medicines, without checking with their doctor; and
  • Get vaccinated against hepatitis A if liver disease is found to be present.
• To reduce the risk for transmission to others, HCV-positive people should be advised to
  • Not donate blood, body organs, other tissue, or semen;
  • Not share toothbrushes, dental appliances, razors, or other personal-care articles that might have blood on them; an
  • Cover cuts and sores on the skin to keep from spreading infectious blood or secretions.
• HCV-positive people with one long-term steady sex partner do not need to change their sexual practices. They should
  • Discuss the risk, which is low but not absent, with their partner (If they want to lower the limited chance of spreading HCV to their partner, they might decide to use barrier precautions [e.g., latex condoms]); and
• Discuss with their partner the need for counseling and testing. HCV-positive women do not need to avoid pregnancy or breastfeeding. Potential, expectant, and new parents should be advised that
  • Approximately 5 out of every 100 infants born to HCV-infected women become infected (This occurs at the time of birth, and no treatment exists that can prevent this from happening);
  • Infants infected with HCV at the time of birth seem to do very well in the first years of life (More studies are needed to determine if these infants will be affected by the infection as they grow older);
  • No evidence exists that mode of delivery is related to transmission; therefore, determining the need for cesarean delivery versus vaginal delivery should not be made on the basis of HCV infection status;
  • Limited data regarding breastfeeding indicate that it does not transmit HCV, although HCV-positive mothers should consider abstaining from breastfeeding if their nipples are cracked or bleeding;
  • Infants born to HCV-positive women should be tested for HCV infection and if positive, evaluated for the presence or development of chronic liver disease
  • If an HCV-positive woman has given birth to any children after the woman became infected with HCV, she should consider having the children tested.
• Other counseling messages
  • Sneezing, hugging, coughing, food or water, sharing eating utensils or drinking glasses, or casual contact does not spread HCV.
  • People should not be excluded from work, school, play, child-care or other settings on the basis of their HCV infection status.
  • Involvement with a support group might help patients cope with hepatitis C.
• HCV-positive people should be evaluated (by referral or consultation, if appropriate) for presence or development of chronic liver disease including
  • Assessment for biochemical evidence of chronic liver disease;
  • Assessment for severity of disease and possible treatment according to current practice guidelines in consultation with, or by referral to, a specialist knowledgeable in this area
  • Determination of need for hepatitis A vaccination.

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)

ribavirin
   
interferon

• Roeferon® (interferon alfa-2a)
• Intron-A® (interferon alfa-2b)
• Infergen® (interferon alfacon-1)

pegylated interferons

• Pegasys® (pegylated interferon alfa 2a)
• Peg-lnton® (pegylated interferon alfa 2b,)

Common side effects of ribavirin include (Al-Saden & Wachs, 2004):

• Hemolytic anemia.
• Increased iron stores in the liver.
• Gout.
• Itching.
• Skin sensitivity to the sun.
• Nasal stuffiness.
• Sinus problems.
• Ear infections.
• Sore throat.
• Depression.
• Nervousness.
• Insomnia.
• Fetal abnormalities.
• Decreased sperm count.
• Increased potential to develop cancer.

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):

• Fatigue.
• Depression.
• Nausea.
• Vomiting.
• Constipation.
• Diarrhea.
• Memory problems.
• Loss of appetite.
• Thinning hair.
• Bone marrow suppression.
• Autoimmune conditions.
• Seizures.
• Worsening of hepatitis.
• Infections.
• Inflammation of the lungs.
• Decrease or changes in vision.
• Decreased sex drive.

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)

• For the source, baseline testing for anti-HCV.
• For the person exposed to an HCV-positive source, baseline and follow-up testing including
  • Baseline testing for anti-HCV and ALT activity; and
  • Follow-up testing for anti-HCV (e.g., at 4–6 months) and ALT activity. (If earlier diagnosis of HCV infection is desired, testing for HCV RNA may be performed at 4–6 weeks.)

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.