CDC Updates, Combines Occupational Exposure Guidelines for HBV, HCV, HIV
The guidelines point out that the risk of contracting HIV or HCV in occupational settings is low, even after direct contact with blood from an infected patient. The HIV-infection risk is 0.3% for percutaneous exposure and 0.09% for mucous-membrane exposure. This risk may be greater if the exposure involves a deep, penetrating injury to the health care worker or contact with large amounts of blood or concentrated virus in a laboratory setting. The risk of HCV infection after percutaneous contact with blood from an infected patient is about 1.8%.
HBV, unlike the other two viruses, is easily transmitted from patients to health care workers. According to CDC, 3762% of health care workers exposed to blood that contains HBV may show serological evidence of infection. Up to 31% of exposed health care workers may be diagnosed with hepatitis. Needlestick injuries involving blood from an HBV-infected patient carry a seroconversion risk of 2337% and a hepatitis risk of 16% if the virus is not in a high-replicating, hepatitis Be antigen-positive state.
HBV exposure. CDC strongly recommends that all health care workers at risk of occupational exposure to blood receive the three-dose HBV vaccination series. Anyone who has not been vaccinated should start the series immediately after exposure to blood, even from an uninfected patient, since future occupational exposures to blood are likely.
CDC recommends postexposure prophylaxis with hepatitis B immune globulin for health care workers who have not received or did not respond to the HBV vaccination series. Vaccine nonresponders are urged to undergo a second three-dose vaccination series after an occupational exposure to HBV.
HCV exposure. According to CDC, clinical evidence does not support treatment with antiviral agents or immune globulin after an occupational exposure to HCV. Instead, CDC recommends monitoring the exposed worker for signs of infection and providing early treatment if HCV-related disease is diagnosed.
HIV exposure. When an occupational exposure involves a patient who is either known to be infected with HIV or likely to harbor the virus, CDC advises immediate treatment of the worker with a four-week regimen consisting of two nucleoside analog reverse-transcriptase inhibitors: zidovudine and lamivudine, lamivudine and stavudine, or didanosine and stavudine.
A three-drug or specialized regimen may be appropriate if the risk of infection is particularly high or the patient is infected with a drug-resistant strain of HIV. The guidelines offer suggestions for devising three-drug treatment plans.
Determining whether a patient is infected with HIV is an important part of managing the treatment of a health care worker after exposure to the patients blood. If the patient cannot be tested for HIV infection but is unlikely to harbor the virus, CDC does not recommend prophylaxis for the exposed worker. If testing reveals that the patient is HIV-seronegative, antiretroviral prophylaxis for the worker, if already begun, should stop.
Since drugs used to treat HIV infections are fairly toxic, CDC recommends that patient testing after an exposure be done using an FDA-approved assay that will give results in 2448 hours. This would allow the exposed worker to stop taking antiretrovirals as soon as possible if the patient is not infected with HIV.
CDC noted that although occupational infection with HIV is uncommon, the emotional distress that follows exposure merits close attention. Postexposure counseling and follow-up HIV testing should be part of the health care organizations exposure-management plan.
Ready access. Health care facilities should have antiretroviral agents, HBV vaccine, and hepatitis B immune globulin on hand or nearby for immediate postexposure prophylaxis. Also important, CDC said, is a well-organized exposure-management plan that delivers these products to workers immediately after an incident occurs.
- Centers for Disease Control and Prevention. Updated U.S. Public Health Service guidelines for the management of occupational exposures to HBV, HCV, and HIV and recommendations for postexposure prophylaxis. MMWR. 2001; 50(RR-11):1-52.