Which exposure would NOT be an indication for Post Exposure Prophylaxis (PEP) in an Australian (low HIV prevalence) context?
- A man presents after sharing needles with another man who he believes may be HIV positive.
- A woman presents following receptive anal intercourse with a HIV + source known to be well controlled on antiretroviral therapy
- A lady presents after unprotected vaginal intercourse with a man from a high HIV prevalence country
- A healthcare worker presents following a needlestick injury in a patient with poorly controlled HIV’
Answer B
New evidence from the partner study suggests that the chance of HIV transmission from a viral load suppressed source is negligible. This groundbreaking study of 1166 serodiscordant partners in whom the HIV+ partner had viral suppression reported 0 cases of HIV transmission between the partners, despite 22,000 condomless sex acts among MSM and 36000 among heterosexual partners. The study was powered to give a 95% upper confidence of 0.3/100 couple years of condomless sex, suggesting that the risk is lower than it was previously thought to be a few years ago.
Add in the the weight of new evidence about the morbidity benefits of ART in the SMART and TEMPRANO trials has led to recent changes in WHO and Australian ASHM, which now recommend starting antiretroviral therapy in almost all HIV patients.
A, C, and D would all be indications for PEP by Australian guidelines. B would not be a indication, nor would even unprotected receptive anal sex with a source with unknown HIV status from the standard Australian low prevalence community – although it could be considered if the source was from a higher prevalence group – eg a country with higher prevalence or a subgroup like IVDU. Remember, this more conservative administration of PEP reflects both new evidence and low Australian prevalence, and many countries might have higher prevalence or not have updated older more conservative guidelines yet.
For tons of extra information including probabilities of transmission risks by different exposures and current indications for PEP check out ASHMs great guidelines here.
http://www.ashm.org.au/products/product/978-1-920773-47-2
And the 2016 WHO guidelines here
http://www.who.int/hiv/pub/arv/arv-2016/en/
THe PARTNER study is here
https://jamanetwork.com/journals/jama/fullarticle/2533066
