Antiretroviral Prophylaxis for Occupational Exposure to HIV

Clinical Question

Should health care workers with occupational exposure to human immunodeficiency virus (HIV) receive postexposure antiretroviral prophylaxis?

Evidence-Based Answer

There are no controlled trials of postexposure prophylaxis for persons with occupational exposure to body fluids potentially infected with HIV. Based on one case-control study, individually selected antiretroviral therapy, initiated soon after exposure, is recommended. Treatment should continue for four weeks or until the source body fluid tests HIV negative.

Practice Pointers

The Centers for Disease Control and Prevention (CDC) defines occupational HIV exposure as a percutaneous injury (e.g., a needlestick, cut from a sharp object) or contact of mucous membranes or nonintact skin (e.g., skin that is chapped, abraded, or affected by dermatitis) with blood, tissue, or other body fluids that are potentially infected with HIV.¹ Potentially infectious fluids include cerebrospinal, synovial, pleural, peritoneal, pericardial, and amniotic fluids. Feces, nasal secretions, saliva, sputum, sweat, tears, urine, and vomit are not considered infectious unless visibly bloody. The risk of HIV transmission is approximately 0.3 percent after percutaneous exposure to infected blood and 0.09 percent after mucous membrane exposure. The risk of transmission varies with the type of exposure and infected fluid.¹

The authors of this Cochrane review searched the literature from 1985 to May 2005. They found no controlled trials of postexposure prophylaxis, but found one case-control study. Participants were health care workers with occupational, percutaneous exposure to HIV-infected blood. Patients in the case group had HIV seroconversion temporally associated with the exposure and no other reported concurrent exposure to HIV. Participants in the control group remained seronegative six months after exposure.

An increased risk of HIV transmission was associated with deep injury, visible blood on the device, procedures involving a needle placed in the source patient's blood vessel, and terminal illness in the source patient. Zidovudine (Retrovir) use after exposure was associated with a lower risk of HIV transmission. Most patients took at least 1,000 mg of zidovudine per day starting within four hours of exposure.

Of 58 health care workers who received postexposure prophylaxis, 71 percent had adverse effects, including nausea (24 percent), fatigue (22 percent), emotional distress (13 percent), and headache (9 percent). Although patients who received a three-drug regimen reported more adverse effects, the drop-out rate in these patients was similar to that in patients who received fewer drugs.

The CDC recommends postexposure prophylaxis for health care workers who have occupational exposure to blood infected with HIV, and it recommends considering prophylaxis for health care workers with percutaneous injuries from sources with unknown HIV status who have risk factors or who are from settings where HIV exposure is likely.¹ Prophylaxis should be initiated as soon as possible, ideally within hours, not days, of exposure. Therapy should continue for four weeks or until the source blood tests HIV negative. Selection of prophylactic medication should be determined in consultation with an expert in antiretroviral therapy and HIV transmission.¹ If expert consultation is not immediately possible, more information on prophylactic regimens is available athttp://www.cdc.gov/mmwr/preview/mmwrhtml/rr5409a1.htm andhttp://www.ucsf.edu/hivcntr/Hotlines/PEPline.html.