There is no vaccine to prevent hepatitis C, and immune globulin is not effective for postexposure prophylaxis. The development of effective pre- and postexposure prophylaxis is complicated because of the genetic diversity of HCV. In the absence of effective preventive measures, and considering the long-term infectious nature of the disease, it is important that those who are positive for anti-HCV be advised on how they can avoid infecting others. Because no tests are available to determine infectivity, it should be assumed that anyone positive for anti-HCV is potentially infectious. All such individuals should be told that HCV is primarily transmitted by exposure to blood, serum-derived body fluids, and body fluids that are visibly contaminated with blood. They should be told what this information means in terms of their day-to-day living and in terminology that they can understand. Persons who are at risk of exposure to HCV also need to be advised on what steps they might take to minimize their risk of becoming infected. The primary measures available to prevent hepatitis C are screening of blood, organ and tissue donors; modification of high-risk behaviors; and use of blood and body fluid precautions.

Counseling Patients to Prevent Transmission from Direct Exposure to Blood

Patients should be given the following messages:

1. Don't donate blood, body organs, other tissue, or semen.

2. Don't share personal household articles that could become contaminated with blood, such as toothbrushes, dental appliances, nail-grooming equipment or razors.

3. Cover cuts and skin lesions to keep from spreading infectious blood or secretions.

4. Don't use or inject illegal drugs; if illegal drugs are used, stop using and injecting drugs.

   • Enter and complete substance abuse treatment, including relapse prevention.

   • Take the following steps to reduce personal and public health risks, if continuing to inject drugs:

     • Never reuse or "share" syringes, water, or drug preparation equipment.

     • Use only syringes obtained from a reliable source (e.g., pharmacies).

     • Use a new sterile syringe to prepare and inject drugs.

     • If possible, use sterile water to prepare drugs; otherwise use clean water from a reliable source (such as fresh tap water).

     • Use a new or disinfected container ("cooker") and a new filter ("cotton") to prepare drugs.

     • Clean the injection site prior to injection with a new alcohol swab.

     • Safely dispose of syringes after one use.

Injection drug use is the most frequently identified risk factor for acquiring hepatitis C. Community-based programs that target the prevention of HIV infection among injecting drug users also should include messages and interventions related to the prevention of HBV (hepatitis B virus) and HCV infections. Physicians should offer hepatitis B vaccine to their patients who inject illicit drugs. Because acquisition of HCV infection is particularly rapid in this high-risk group, early intervention to prevent infection is essential. HCV transmission associated with drug injection can be prevented through a variety of approaches. First, preventing the initiation of drug injection avoids the infection risks associated with this behavior. Similarly, if a person who injects drugs can completely stop injecting, future risks of HCV transmission are eliminated. Substance abuse treatment can help the person who injects drugs reduce the amount of drug injection and ideally eliminate it entirely. For injection drug users who continue to inject, prevention strategies for HCV are similar to those for HIV and would reduce the chance that blood and bloodborne agents would be transferred among injection drug users. Injection drug users should use new, sterile syringes and needles -- not only for every injection but also to prepare and distribute dissolved drug solutions; they should also use cookers, cotton, and water that have not been used by another injection drug user. The chance for transfer of blood should be minimal if these practices are followed. Changing the prescription and paraphernalia laws to make it easier for drug users to obtain and possess syringes, and supporting syringe exchange programs are important steps in achieving these safer injection practices.

Counseling Patients to Prevent Sexual Transmission

1. For persons with a steady partner, there are no recommendations for changes in sexual practices.

2. For persons with multiple partners, safer sex should be recommended. They should

   • Reduce the number of partners.

   • Inform all prospective partners of their anti-HCV positivity.

   • Use latex condoms. The efficacy of latex condoms in preventing infection with HCV is unknown, but their proper use may reduce transmission.

For HCV-infected persons with a steady partner, there are no specific recommendations for changes in sexual practices, because it appears from studies of persons in monogamous relationships that the risk of transmission through sexual activity is very low. However, HCV-infected persons should be informed of the potential risk for sexual transmission to assist them in making decisions about precautions. The decision whether to use or not to use barriers for sexual practices should be made by both partners. It may be prudent to abstain from sexual intercourse or use barrier precautions during the menstrual cycle. Consideration should also be given to testing exposed sexual partners for anti-HCV, and if positive, evaluating them for the presence or development of chronic liver disease. HCV-infected individuals who have multiple sex partners should be advised that having more than one sex partner increases their risk of acquiring other sexually transmitted diseases (STDs), and they should practice "safer sex" to avoid acquiring other STDs as well as to prevent transmitting HCV infection to their partners.

Counseling Pregnant Patients and Parents

There are no recommendations advising against pregnancy or breast-feeding. Potential, expectant, and new parents should be advised that there is about a 5% risk of HCV-infected women transmitting HCV to their newborns, and that the data on the safety of breast-feeding are limited but indicate that breast-feeding does not transmit HCV. There are a small number of follow-up studies of HCV-infected infants that indicate that these infants do well in the short term. At present, there are no data from long-term follow-up.

• Routine screening of pregnant women for anti-HCV is not recommended.

• Infants born to anti-HCV positive women should be tested for anti-HCV after 12 months of age. If positive, infants should be evaluated for the presence or development of CLD.

• Children with HCV-related severe disease or histologically advanced pathology should be referred to a specialist in the management of chronic HCV infection.

Counseling Patients on Other Issues

Patients should also be counseled on what they can do to reduce the severity of the disease. Patients should be warned of the dangers of coinfection with other viruses or another strain of HCV, and the recommendations given above for preventing transmission of HCV to others also will serve to protect themselves. Patients with chronic liver disease should be offered hepatitis A vaccine and should be told to avoid the use of alcohol. Over-the-counter and other medications should be taken only with a physician's knowledge, and patients should inform medical and dental providers of their anti-HCV positivity. Patients are becoming more interested in alternative medicine, such as traditional Chinese medicine, naturopathy, and homeopathy, and physicians should be prepared to address questions on these topics.

There are many aspects of hepatitis C that are not clearly understood and that make recommendations for prevention and counseling difficult. It is important that patients be under the care of a physician who is knowledgeable about hepatitis C. It may also be helpful for patients to become involved with a support group to help them work through the process of accepting their diagnosis and to help them learn how to live with hepatitis C.

Postexposure Follow-Up of Health Care Workers

There is no vaccine for hepatitis C, and postexposure prophylaxis with immune globulin is not recommended. There are no data on the prevention of HCV infection with anti-viral agents (e.g., alpha interferon), and mechanisms of the effect of interferon treatment for patients with hepatitis C are poorly understood; established infection may need to be present for interferon to be effective. Interferon must be administered by injection, and patients receiving treatment can experience side effects. Based on these considerations, no postexposure prophylaxis regimens with anti-viral agents for HCV infection are currently recommended.

In the absence of effective prophylaxis, persons who have been exposed to HCV may benefit from knowing their infection status so that they can seek evaluation for chronic liver disease and treatment. It is recommended that individual institutions consider implementing policies and procedures for follow-up after percutaneous or permucosal exposures to blood. At a minimum such policies should include

1. For the source, baseline testing for anti-HCV

2. For the person exposed to an anti-HCV positive source, baseline and follow-up (e.g., 6-month) testing for anti-HCV and ALT activity

3. Confirmation by supplemental anti-HCV testing of all anti-HCV results reported as repeatedly reactive by EIA

4. Recommending against postexposure prophylaxis with immune globulin or anti-viral agents (e.g., interferon)

5. Education of health care workers about the risk for and prevention of bloodborne infections, including hepatitis C, in occupational settings, with the information routinely updated to ensure accuracy

Several studies suggest that interferon treatment begun early in the course of HCV infection is associated with a higher rate of resolved infection. After an exposure, the use of PCR to measure HCV RNA could detect the onset of HCV infection earlier than the use of EIA to measure anti-HCV. However, PCR is not a licensed assay, and the accuracy of the results are highly variable. There are no data indicating that treatment begun in the acute phase of infection is more beneficial than treatment given early in the course of chronic HCV infection. Furthermore, alpha interferon is approved for the treatment only of chronic hepatitis C.

There are currently no recommendations regarding restriction of health care workers with hepatitis C. The risk of transmission from an infected health care worker to a patient appears to be very low. Furthermore, there are no serologic assays that can determine infectivity nor are there data to determine the threshold concentration of virus required for transmission. As recommended for all health care workers, those who are anti-HCV positive should follow strict aseptic technique and standard (universal) precautions, including appropriate use of hand washing, protective barriers, and care in the use and disposal of needles and other sharp instruments.