Updated August 24, 2015.

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In 1996, the U.S. Public Health Service (USPHS) issued the first guidance on the use of antiretroviral drugs (ARVs) as post-exposure prophylaxis (PEP) in cases of occupational exposure to HIV by healthcare personnel (HCP).

In 2013, the USPHS updated the guidelines for the fourth time, basing their recommendations on the availability and effectiveness of newer-generation ARVs, as well as up-to-date data on the long-term safety of ARVs previously endorsed for use.

Among the considerations of the review panel:

• Overall effectiveness of candidate ARVs
• Tolerability and toxicities
• Drug safety in pregnancy and during lactation
• Pill burden and frequency of dosing

Defining Occupational Exposure

Exposure to HIV among HCP is defined as either a percutaneous injury (e.g., a needlestick or cut from a sharp object), or contact of mucous membrane or non-intact skin (e.g. chapped, abraded or afflicted with dermatitis) with HIV-infected blood, tissue, or other body fluids considered potentially infectious.

These include cerebrospinal fluid, amniotic fluid, pericardial fluid (fluid from the membrane surrounding the hear), synovial fluid (fluid from around the joints), pleural fluid (fluid from the membranes surrounding the lungs); and peritoneal fluid (lubricating fluids from within the abdominal cavity).

Feces, nasal secretions, saliva, sputum, sweat, tears, urine and vomit are not considered potentially infectious unless visibly bloody. Moreover, while human bites should be evaluated individually, there have been no documented cases of HIV transmission through human bites in a healthcare setting.

Key Changes in the 2013 USPHS Guidelines

The previous guidelines, issued in 2005, recommended that the severity of exposure be assessed to determine whether to employ two or more ARVs. That recommendation has fallen away entirely, and the USPHS now endorses the use of three or more ARVs for all occupational exposures.

The updated guidelines further suggest that the use of fourth-generation antigen/antibody tests could reduce the post-treatment testing period from six months to four months.

Overview of Guidelines

In the event of occupational exposure to HIV,

1. PEP should be implemented immediately, ideally within hours of exposure. Expert consultation should always be sought, but not at the expense of delaying therapy.
2. A baseline HIV test would be given to determine the HIV status of the HCP. When possible, the HIV status of the source patient should be be sought to help guide the appropriate use of PEP.
3. Three or more ARVs would be prescribed, based on a favorable side effect profile and a convenient dosing schedule. (See Recommended Drug Options, below.) Known or suspected pregnancy (or breastfeeding) would further determine the choice of drugs in some.
4. In addition to a baseline HIV test, the HCP should be given the necessary baseline lab tests to anticipate drug toxicities. The tests should include, minimally, a complete blood count (CBC), as well as kidney and liver function tests.
5. PEP would commence and continue for the course of 28 days. Pre-treatment counseling should be provided to address proper adherence, possible side effects, and possible drug interactions.
6. Follow-up appointments should begin within 72 hours of exposure, and include follow-up HIV testing and counseling. A second lab monitoring for drug toxicities should be performed at two weeks.
7. Thereafter, HIV testing should be performed at six weeks, 12 weeks, and six months after exposure. If a fourth-generation combination HIV p24 antigen/HIV antibody test is used, follow-up testing can be performed at six weeks and four months after exposure.

Recommended Drug Options

The USPHS recommends the use of Viread (tenofovir) and Emtriva (emtricitabine)—or the combination of two drugs in the single-pill formulation, Truvada—plus Isentress (raltegravir) for PEP in incidences of occupational exposure.

Alternatives for these drugs can be used in the event of underlying renal disease or other conditions that might contradict the use of the suggested medications.

Viramune (nevirapine) should never be prescribed for PEP, while ARVs not routinely recommended for PEP should be avoided. These include Videx (didanosine) and Aptivus (tipranavir), as well as the combination of Zerit (stavudine) and Videx.

The HIV/AIDS Channel of About.com is pleased to have been named one the "Best HIV/STD Health Blogs" of 2015 by the editors of San Francisco-based Healthline.

_Source:

_{Kuhar, D.; Henderson, D.; Struble, K.; et al. "Updated US Public Health Service Guidelines for the Management of Occupational Exposures to Human Immunodeficiency Virus and Recommendations for Postexposure Prophylaxis."Infection Control and Hospital Epidemiology. August 6, 2013; 34(9): 875-892.}