Thanks to recent medical advances, HIV is an infection that is now considered a chronic disease rather than a death sentence. HIV positive individuals have an increasingly better life expectancy and life quality, including the possibility of an active sexual life with HIV negative partners.
Today’s tools of HIV protection are a combination of drugs such as tenofovir and emtricitabine (brand name Truvada) for PrEP (Pre-Exposure Prophylaxis) and PEP (Post Exposure Prophylaxis), two relatively new preventive approaches that have revolutionized the lives of many HIV negative individuals, helping reduce the risk of transmission after high–risk exposure by nearly 92%, according to the Centers for Disease Control and Prevention.
In spite of Truvada’s newly gained popularity, some relevant facts are still not commonly known.
Post exposure prophylaxis is effective and recommended if started within 72 hours from the risky exposure. Some HIV viral forms develop in a matter of hours, therefore it would be best to start the treatment as soon as possible. The Emergency Room would be the right place to look for assistance after a risky encounter.
In spite of its common nickname of “morning after for HIV”, PEP requires a 28 day treatment with a combination of different drugs. A follow up with a specialist is also necessary and, in any case, the effectiveness is not certain so the exposed individual will need to get tested for HIV.
A randomized, placebo controlled clinical trial will probably never be conducted to prove definitively the effectiveness of PEP for nonoccupational HIV exposure (e.g. sexual encounters with HIV positive partner). Due to ethical and logistical reasons the Centers for Disease Control and Prevention (CDC) stated that this clinical trial would not be performed. The data supporting the use of antiretroviral therapy for PEP in nonoccupational exposures is thus limited to studies on animals, observational studies, and clinical data in other patient populations, such as healthcare personnel.
Side Effects are not the only barriers of Post-exposure Prophylaxis; costs are a limiting factor as well. A dosage of PEP medications may cost more than 700 euro, and the expenses increases as follow up visits and additional tests are necessary to check the patient’s HIV status.
There are specific recommendations for the use of post-exposure prophylaxis in nonoccupational settings, aiming to minimize unnecessary use of antiviral medications. PEP is recommended for:
These three criteria should all be present in order to be considered at high enough risk of HIV to be prescribed PEP.
Another case is when the source patient is known to be HIV infected. In this case the PEP is recommended for a broader set of cases.
If the HIV status of the source is unknown, the CDC guidelines recommend to determine the need of PEP on a case-by-case basis.
Whenever possible, the source should be tested for HIV to assess the level of risk. Regular STD screening is a good way to keep track on the presence of potentially contagious infections.
PEP appears to be a newly invented safety belt protecting from HIV post-exposure.
Practicing safe sex, using condoms, counseling with a professional and other behavioral interventions are more cost effective ways to avoid HIV infection in the general population, reserving drug treatment for the highest risks.
Even though we now have the PEP option, let’s all remember to not use it to encourage risky behavior: with or without safety belt, it’s always better not to be in a car crash!