High Interest in Syphilis Pre-exposure and Post-exposure Prophylaxis Among Gay, Bisexual and Other Men Who Have Sex With Men in Vancouver and Toronto

Abstract

Background We assessed the acceptability of doxycycline-based syphilis pre-exposure and post-exposure prophylaxis (PrEP/PEP) as well as human immunodeficiency virus (HIV) PrEP/PEP in gay, bisexual, and other men who have sex with men (gbMSM). Methods We recruited gbMSM from Toronto and Vancouver sexually transmitted infection (STI) clinics during routine visits from June 2018 to August 2018. We analyzed data using descriptive statistics and constructed multivariable logistic regression models for willingness to use syphilis and HIV PrEP and PEP respectively. Results Among 424 participants (56.4% Toronto, 43.6% Vancouver), median (interquartile range [IQR]) age was 31.0 years (26.0–39.0 years), 61.7% had completed postsecondary education and 54.4% were white. Median (IQR) number of male partners in the past 6 months was 6.0 (3.0–13.0), and 18.2% had 1 or more prior syphilis diagnosis. 60.1%/44.1% indicated willingness to use syphilis PEP/PrEP; 36.6% were unwilling to use either. Among HIV-negative participants, 74.0% and 75.2% were willing to use HIV PrEP and PEP, respectively. Most participants were familiar with antibiotic resistance (89.0%) and agreed that syphilis rates are rising in Canada (68.2%), but only 55.4% believed they were at risk for syphilis. Agreement with the latter statement was associated with willingness to use syphilis PrEP (adjusted odds ratio [aOR], 1.6; 95% confidence interval [95%CI], 1.0–2.5), as was previous/existing HIV PrEP use (aOR, 2.2; 95% CI, 1.1–4.3) and being “very concerned” about STI acquisition (aOR, 1.9; 95% CI, 1.0–3.4). Odds of being willing to use syphilis PEP were higher in Toronto versus Vancouver (aOR, 2.0; 95% CI, 1.2–3.4) and increased with the number of different STIs previously diagnosed (aOR, 1.4; 95% CI, 1.2,1.7). Conclusions There is considerable interest in syphilis PrEP/PEP in gbMSM attending Toronto/Vancouver STI clinics.

Interest in Hypothetical Preexposure Prophylaxis Against Herpes Simplex Virus: A Cross-Sectional Survey

“…In this 2018 cross-sectional survey of Toronto and Vancouver gbMSM attending sexual health clinics, we found moderately high willingness to use hypothetical HSV PrEP, at 61.8%. Similar to our previous findings on syphilis chemoprophylaxis, 10 this willingness was associated with prior STI burden and HIV PrEP use.…”

“…The primary purpose of the survey was to examine interest in syphilis chemoprophylaxis strategies; those results are published. 10 To examine interest in HSV PrEP, we assumed that this would take the form of a safe, existing, oral antiviral such as valacyclovir, and that delivery models would be similar to HIV PrEP. 11 Participants were presented with an introductory paragraph about HSV (Supplemental Digital Content 1, http://links.lww.com/OLQ/A593 ) and the following description: “Herpes PrEP would involve taking one anti-herpes pill every day to prevent HSV.…”

A systematic review of the impacts of oral tetracycline class antibiotics on antimicrobial resistance in normal human flora

“…In a cross-sectional survey in gbMSM attending Toronto and Vancouver STI clinics, willingness to use was 44.1% for PrEP and 60.1% for PEP. 59 In online studies, 52.7%–75.8% of Australian gbMSM said they would be prepared to use STI PrEP, while 84% of American gbMSM expressed interest in STI PEP. 60 The numerically higher interest in PEP in these studies is of interest, as the decreased burden of drug compared with PrEP could theoretically mitigate AMR risk.…”

Testing as Prevention of Resistance in Bacteria Causing Sexually Transmitted Infections—A Population-Based Model for Germany

“…Subtherapeutic dosages of antibiotic drugs, which can facilitate the selection of antimicrobial resistance, are likely to occur in case of blind therapy of a suspected STI without appropriate microbiological diagnosis, as is still frequently the case [ 1 ]. Alternatively, this situation may occur if preexisting, asymptomatic bacterial STIs coincide with off-label application of antibiotics, such as doxycycline for pre-exposure prophylaxis (PrEP) or post-exposure prophylaxis (PEP) approaches as practiced by sexually highly active populations with considerable success regarding the prevention of syphilis and Chlamydia -associated urethritis [ 21 , 22 , 23 , 24 ]. In addition, single-dose application of azithromycin (e.g., for the treatment of gonococcal or chlamydial urethritis) has been reported to trigger the selection of macrolide resistance in M. genitalium [ 25 ].…”