This is the 4th HIV transmission that we know - that has been reported and published or presented at a conference.
The paper say the infected person was fully adherent as others say because the test - the TDF-DP levels in dried blood spots test - says he was adherent - do we know for sure that this test is perfect?? If a person misses one dose on a daily PrEP regimen will they test always pick this up??
This person was exposed to a lot of HIV & perhaps when the transmission occurred he had a lot of HIV onboard from multiple condomless free exposures & perhaps PrEP levels were a little low at that moment, maybe he missed a dose despite dried spot saying he was adherent, or perhaps PrEP levels were lower that day for some reason or the HIV levels were just so high that they overcame the PrEP protection. We will never know the answer in this case but this incident shows to me PrEP is not perfect.
Look how much HIV this person was exposed to a lot - 1 to 5 partners with condomless anal sex - 100 events & 90 partners over past several months.
The paper authors concluded:Lower levels of TDF and/or FTC in rectal mucosa? - Underlying mechanism remains speculative: High repeated HIV exposure and/or mucosal damage? , Lower levels of TDF and/or FTC in rectal mucosa?
Clinical trials show that pre-exposure prophylaxis (PrEP) with tenofovir/emtricitabine is highly effective against acquisition of HIV-infection. World-wide, only two cases of PrEP failure have been reported under adequate tenofovir-diphosphate (TFV-DP) levels in dried blood spots. Both these individuals were infected with a multi-class resistant virus.
CROI: Acute infection with a wild-type HIV-1 virus in a PrEP user with high TDF levels - (02/20/17)