Post-Exposure Prevention (PEP); What to Do If the Condom Breaks?
When healthcare workers have serious exposure to HIV (through a needlestick, for example), they are likely to be started on a two- or three-drug regimen within hours (within two hours if possible), and continue taking the drugs for four weeks. The U.S. Centers for Disease Control and Prevention (CDC) has published guidelines recommending this preventive care, since observational studies had suggested (although not proved) that use of AZT alone reduced the risk of HIV infection by about four fifths.But the guidelines say nothing about preventing HIV infection after exposure through sexual contact, or through needle sharing by injection drug users, even though the risk is biologically similar. Programs are now beginning in a few areas (including San Francisco) to provide such treatment, together with counseling and other services which may be needed (for example, hepatitis B and C testing, and hepatitis B vaccination). In other areas where there are no programs, the same drugs can be prescribed by any doctor, since they are FDA approved and commercially available; however, at this time few doctors know about preventive treatment after sexual exposure.
Treatment must start as soon as possible after the incident. Many experts believe that after 72 hours it is too late, since the virus will already be integrated into human cells. In practice it is difficult to get into treatment within 72 hours after an accidental exposure--especially if those exposed, and friends or associates they turn to for advice, do not know ahead of time that such treatment is available, and do not know how to contact a program or doctor who can provide it.
Fortunately this preventive treatment lasts only for four weeks and then the drugs are stopped. Therefore it does not involve a commitment to long-term antiretroviral use. The PEP programs include counseling to help people reduce the risk of further exposures.
In San Francisco alone, it is estimated that 600 to 800 people become HIV-positive each year. Hopefully, post-exposure prevention can be one part of the efforts to prevent these infections.
In or Near San Francisco
In the San Francisco area (if you live close enough that you can come in for repeated visits), you can join a local research program for non-occupational exposure; it pays for the drugs, tests, and other expenses, and provides counseling and certain other services as needed. You will be encouraged to give your real name, but if that is a problem, the staff will accept whatever name you give. There is no placebo, and you can stay in this program to benefit from the testing, etc., even if you choose not to take the drugs. The drugs are used for four weeks, and then there are occasional visits for followup blood tests. The entire program lasts one year, and includes nine visits to the research clinic.
If you live in or near San Francisco and have been accidentally exposed to HIV, call the research program hotline number, 415-514-4PEP, 24 hours a day (the previous number, 415-502-5PEP, will also work; the new one may be easier to remember). You may need to leave a phone number for a return call, which you will probably receive within half an hour. Or you can drop in at the PEP site, during certain hours, at either of two locations: San Francisco General Hospital Ward 4C, or the City Clinic on 7th Street between Harrison and Folsom. No appointment is needed, but call the number above to check when the clinics are open. Do not wait for open hours; use the telephone hotline so that if you are found to need treatment, it can be started immediately.
Other Locations
If exposed to HIV, you need to locate either a PEP program, or a PEP-knowledgeable physician. Unfortunately there is no national list of programs. A local AIDS service organization may be able to help; you can find one in your area by calling the National AIDS Hotline, 800-342-AIDS, 24 hours a day. (For a Spanish-speaking operator, call 800-344-SIDA, 8 a.m. to 2 a.m. Eastern time; for TTY, call 800-243-7889, 10 a.m. to 10 p.m. Monday through Friday Eastern time.)
Who Is Likely to Need Treatment?
Here are some of the guidelines used by the PEP program in San Francisco to decide who may benefit from drug treatment. Other PEP programs, or private physicians experienced with PEP, are likely to use similar criteria.
There must be a "significant" sexual or injection drug use exposure. "A significant sexual exposure is when a person has receptive or penetrative anal intercourse, receptive or penetrative vaginal intercourse or receptive oral intercourse with ejaculation. Significant sexual exposures are always without a condom (or when the condom breaks) and with someone who is HIV infected. Since it is not always possible to know if the person you are having sex with is HIV infected, PEP should be offered to anyone who has had a significant sexual exposure with a 'high risk' partner. High risk partners are men who have had sex with men, anyone with a history of injection drug use, sex workers, and anonymous partners." (Quoted from Twenty Top Questions and Answers about PEP; to obtain this document, see "For More Information," below.)
What Treatment Is Used?
Most people are treated with AZT plus 3TC for four weeks. The drugs are combined into a single tablet (called Combivir(tm)); the adult dose is one tablet, taken twice a day.
The San Francisco program also offers an alternative of ddI and d4T, for those who do not want to take AZT, or when the alternative is indicated by the partner's treatment history.
If it is suspected from clinical history that the patient's partner may have drug-resistant HIV, then a third antiretroviral may be added--the protease inhibitor nelfinavir.
Besides the antiretrovirals, the program includes counseling on risk reduction, testing for sexually-transmitted diseases and treatment if necessary, hepatitis B and C screening and hepatitis B vaccination or referral, and pregnancy testing. (Pregnant women are allowed to enter the program and use the antiretroviral drugs.)
What Has Been Learned So Far?
At this time about 150 people have been treated; no one has become HIV positive. Since the risk from a single exposure is fairly small, this could have happened by chance.
There has been no serious toxicity of the medications, and over 80% of the volunteers have completed the full four weeks of treatment.
One of the concerns of the program--that people would take more risks because of it--is too early to evaluate with the short follow-up so far.
For More Information
Several documents about post-exposure prevention, and the San Francisco program in particular, are available on the Web. The most important are:
"Twenty Top Questions and Answers about PEP." At (URL no longer available), select "Post Exposure Prevention" in the list of topics, then select "PEP: The San Francisco Feasibility Study," then select "Top Twenty Questions..." Many other documents about PEP, and the San Francisco study of non-occupational exposure, are also available on this site.
"What Is Post-Exposure Prevention (PEP)?" Select this article at http://www.caps.ucsf.edu/PEP.html.
"San Francisco PEP Update: What Happens," by Bill Snow and Larry Hanbrook, ACT UP/Golden Gate Writers' Pool, published in Bay Area Reporter, April 2, 1998. Go to http://www.actupny.org/indexfolder/actupgg.html, select "Writers' Pool articles," select "1998," then select the article, in the list which is sorted by date. (Note: The organization of this site, and the other sites also, may change in the future.)
Background on PEP for occupational exposure to HIV and other blood-borne illnesses can be found at http://www.ucsf.edu/hivcntr/resources/pep/
The government guidelines for occupational exposure (Public Health Service Guidelines for the Management of Health-Care Worker Exposures to HIV and Recommendations for Postexposure Prophylaxis) can be found at many Web sites; the document has been translated into convenient Web format (to avoid a separate download step) at (website no longer available) (select "Guidelines"). As of this writing, the current version was published May 15, 1998.
