RT Journal Article SR Electronic T1 Evidence of HIV pre-exposure or post-exposure prophylaxis (PrEP/PEP) among blood donors: a pilot study, England June 2018 to July 2019 JF Sexually Transmitted Infections JO Sex Transm Infect FD BMJ Publishing Group Ltd SP sextrans-2021-054981 DO 10.1136/sextrans-2021-054981 A1 Heli Harvala A1 Claire Reynolds A1 Samreen Ijaz A1 Vicki Maddox A1 Sujan Dilly Penchala A1 Alieu Amara A1 Laura Else A1 Susan Brailsford A1 Saye Khoo YR 2021 UL http://sti.bmj.com/content/early/2021/03/28/sextrans-2021-054981.abstract AB Objective Due to increased use of pre-exposure prohylaxis (PrEP) and its potential to affect HIV screening of blood donors, we undertook antiretroviral residual testing among HIV-negative male donors in England.Methods Residual plasma samples were obtainnd from 46 male donors confirmed positive for syphilis and 96 donors who were repeat reactive for HIV antibodies in screening but confirmed as HIV-negative by reference testing. These were tested for concentrations of tenofovir and emtricitabine by high-performance liquid chromatograhpy coupled with mass spectrometry.Results We found evidence of pre-exposure or post-exposure prophylaxis (PrEP/PEP) use in three male blood donors confirmed positive for syphilis (3 out of 46 screened, 6.5%). Two were estimated to have taken PrEP/PEP within a day of donating, and the third within 2 days. Two were new donors, whereas one had donated previously but acquired syphilis infection after his last donation.Conclusions Our findings indicate that a small proportion of blood donors have not been disclosing PrEP/PEP use and therefore donating in non-compliance to donor eligibility criteria.