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    Sex is associated with the persistence of non-optimal vaginal microbiota following treatment for bacterial vaginosis: a prospective cohort study
    Ratten, LK ; Plummer, EL ; Murray, GL ; Danielewski, J ; Fairley, CK ; Garland, SM ; Hocking, JS ; Tachedjian, G ; Chow, EPF ; Bradshaw, CS ; Vodstrcil, LA (WILEY, 2021-03)
    OBJECTIVE: Determine the associations between factors and sexual practices and the composition of the vaginal microbiome (VM) of women treated for bacterial vaginosis (BV). DESIGN: Prospective cohort study. SETTING: The Melbourne Sexual Health Centre, Melbourne, Australia. POPULATION: Seventy-five reproductive-age women diagnosed with clinical BV, treated with first-line antibiotics and followed for up to 6 months. METHODS: Women self-collected vaginal swabs and completed questionnaires at enrolment, the day following antibiotics and monthly for up to 6months until BV recurrence or no BV recurrence (n = 430 specimens). Bacterial composition was determined using 16S rRNA gene amplicon sequencing. The effects of ongoing factors on VM composition (utilising 291 monthly specimens) were assessed using generalised estimating equations population-averaged models, which accounted for repeated measures within individuals. MAIN OUTCOME MEASURES: The relative abundance of vaginal bacterial taxa. RESULTS: Women who reported ongoing sex with a regular sexual partner (RSP) had a VM comprised of increased relative abundance of non-optimal BV-associated bacteria (Adjusted co-efficient [Adjusted co-eff] = 11.91, 95% CI 3.39to20.43, P = 0.006) and a decreased relative abundance of optimal, Lactobacillus species (Adjusted co-eff = -12.76, 95% CI -23.03 to -2.49, P = 0.015). A history of BV was also associated with a decreased relative abundance of Lactobacillus spp. (Adjusted co-eff = -12.35, 95% CI -22.68, P = 0.019). The relative abundance of Gardnerella, Atopobium and Sneathia spp. increased following sex with an RSP. CONCLUSIONS: Sex with an untreated RSP after BV treatment was associated with a VM comprised of non-optimal BV-associated bacteria. BV treatment approaches may need to include partner treatment if they are to achieve a sustained optimal VM associated with improved health outcomes. TWEETABLE ABSTRACT: Sex drives a return to a 'non-optimal' vaginal microbiota after antibiotics for bacterial vaginosis.
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    Factors Associated With Early Resumption of Condomless Anal Sex Among Men Who Have Sex With Men After Rectal Chlamydia Treatment
    Lau, A ; Kong, FYS ; Fairley, C ; Templeton, DJ ; Amin, J ; Boyd, MA ; Bradshaw, CS ; Chen, MY ; Donovan, B ; Khaw, C ; Lewis, DA ; McNulty, A ; Regan, DG ; Ratnayake, M ; Hocking, J (LIPPINCOTT WILLIAMS & WILKINS, 2020-06)
    BACKGROUND: The resumption of sexual activity shortly after commencing treatment for sexually transmitted infections (STIs) is poorly described despite contributing to onward transmission. With azithromycin remaining an option for rectal Chlamydia trachomatis, resuming sex too early after treatment may contribute to antimicrobial resistance because of exposure of newly acquired STIs to subinhibitory concentrations. METHODS: Clinical and sexual behavioral data were collected from men participating in a trial assessing treatment efficacy for rectal chlamydia. Data were collected at recruitment and weekly for 3 weeks after commencing treatment. Outcome measures were resumption of any sexual activity or condomless receptive anal sex within 1, 2, or 3 weeks after commencing treatment. Generalized linear regression was used to calculate adjusted risk ratios (aRR) to identify associated factors. RESULTS: Almost 1 in 10 men (9.5%; 95% confidence interval [CI], 7.2-12.1) resumed condomless receptive anal sex within 1 week of commencing treatment. This was associated with current preexposure prophylaxis use (aRR, 3.4; 95% CI, 2.5-4.8]) and having 9 or more sexual partners in the last 3 months (aRR, 3.2; 95% CI, 1.6-5.0). Most men (75.0%; 95% CI, 71.3-78.5) resumed any sexual activity within 3 weeks; this was associated with a greater number of sexual partners (4-8 partners; aRR, 1.2; 95% CI, 1.1-1.5; ≥9 partners; aRR, 1.5; 95% CI, 1.3-1.7). CONCLUSIONS: Resuming condomless receptive anal sex early after treatment may facilitate onward transmission and promote antimicrobial resistance for STIs. Although azithromycin remains a treatment option, this analysis highlights the need for new health promotion messages regarding early resumption of sex and continued surveillance for antimicrobial resistance.
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    Bacterial Load of Chlamydia trachomatis in the Posterior Oropharynx, Tonsillar Fossae, and Saliva among Men Who Have Sex with Men with Untreated Oropharyngeal Chlamydia
    Phillips, TR ; Fairley, CK ; Maddaford, K ; Danielewski, J ; Hocking, JS ; Lee, D ; Williamson, DA ; Murray, G ; Kong, F ; De Petra, V ; Bradshaw, CS ; Chen, MY ; Wigan, R ; Snow, A ; Howden, BP ; Garland, SM ; Chow, EPF ; Munson, E (AMER SOC MICROBIOLOGY, 2020-01)
    The aim of this study was to determine whether Chlamydia trachomatis could be detected in saliva and if infection is specific to an anatomical site in the oropharynx. Men who have sex with men (MSM) who were diagnosed with oropharyngeal chlamydia at the Melbourne Sexual Health Centre in 2017-2018 were invited to participate upon returning for treatment. Swabs at the tonsillar fossae and posterior oropharynx and a saliva sample were collected. Throat samples were tested for C. trachomatis by the Aptima Combo 2 assay. The bacterial loads of C. trachomatis in all samples were assessed by quantitative PCR (qPCR) detecting the ompA gene. We calculated the positivity and bacterial load of C. trachomatis for all samples. Forty-two MSM were included. The median age was 28 years (interquartile range [IQR], 24 to 33 years). Thirty-two participants (76.2%; 95% confidence interval [CI], 60.5% to 87.9%) had C. trachomatis detected by qPCR at both the tonsillar fossae and the posterior oropharynx, followed by 9.5% (n = 4; 95% CI, 2.7% to 22.6%) positive at the posterior oropharynx only and 4.8% (n = 2; 95% CI, 0.58% to 16.2%) positive at the tonsillar fossae only. Twenty-nine MSM had C. trachomatis detected in saliva (69.0%; 95% CI, 52.9% to 82.3%). The median C. trachomatis load in saliva was 446 copies/ml (IQR, 204 to 1,390 copies/ml), that in the tonsillar fossae was 893 copies/swab (IQR, 390 to 13,224 copies/ml), and that in the posterior oropharynx was 1,204 copies/swab (IQR, 330 to 16,211). There was no significant difference in C. trachomatis load between the tonsillar fossae and the posterior oropharynx (P = 0.119). Among MSM with oropharyngeal chlamydia, nearly three-quarters had chlamydia DNA detected in saliva, although the viability and implications for transmission are unknown.