Incidence of sexually transmitted infections in men who have sex with men and who are at substantial risk of HIV infection - A meta-analysis of data from trials and observational studies of HIV pre-exposure prophylaxis.

Werner RN ，Gaskins M ，Nast A ，Dressler C ... -  《PLoS One》

Quantifying heterogeneity in sexual behaviour and distribution of STIs before and after pre-exposure prophylaxis among men who have sex with men.

Objectives: Pre-exposure prophylaxis (PrEP) use may influence sexual behaviour and transmission of STIs among men who have sex with men (MSM). We aimed to quantify the distribution of STI diagnoses among MSM in the Netherlands based on their sexual behaviour before and after the introduction of PrEP. Methods: HIV-negative MSM participating in a prospective cohort study (Amsterdam Cohort Studies) completed questionnaires about sexual behaviour and were tested for STI/HIV during biannual visits (2009-2019). We developed a sexual behaviour risk score predictive of STI diagnosis and used it to calculate Gini coefficients for gonorrhoea, chlamydia and syphilis diagnoses in the period before (2009 to mid-2015) and after PrEP (mid-2015 to 2019). Gini coefficients close to zero indicate that STI diagnoses are homogeneously distributed over the population, and close to one indicate that STI diagnoses are concentrated in individuals with a higher risk score. Results: The sexual behaviour risk score (n=630, n visits=10 677) ranged between 0.00 (low risk) and 3.61 (high risk), and the mean risk score increased from 0.70 (SD=0.66) before to 0.93 (SD=0.80) after PrEP. Positivity rates for chlamydia (4%) and syphilis (1%) remained relatively stable, but the positivity rate for gonorrhoea increased from 4% before to 6% after PrEP. Gini coefficients increased from 0.37 (95% CI 0.30 to 0.43) to 0.43 (95% CI 0.36 to 0.49) for chlamydia, and from 0.37 (95% CI 0.19 to 0.52) to 0.50 (95% CI 0.32 to 0.66) for syphilis comparing before to after PrEP. The Gini coefficient for gonorrhoea remained stable at 0.46 (95% CI 0.40 to 0.52) before and after PrEP. Conclusions: MSM engaged in more high-risk sexual behaviour and gonorrhoea diagnoses increased after PrEP was introduced. Chlamydia and syphilis diagnoses have become more concentrated in a high-risk subgroup. Monitoring the impact of increasing PrEP coverage on sexual behaviour and STI incidence is important. Improved STI prevention is needed, especially for high-risk MSM.

van Wees DA ，Diexer S ，Rozhnova G ，Matser A ，den Daas C ，Heijne J ，Kretzschmar M ... -  《-》

Low incidence of HIV infection and decreasing incidence of sexually transmitted infections among PrEP users in 2020 in Germany.

Objectives of this study, as part of a nation-wide HIV pre-exposure prophylaxis (PrEP) evaluation project, were to determine the incidence of infections with HIV, chlamydia, gonorrhea, syphilis, hepatitis A/B/C in persons using PrEP, and to describe the health care funded PrEP use in Germany. Additionally, factors associated with chlamydia/gonorrhea and syphilis infections were assessed. Anonymous data of PrEP users were collected at 47 HIV-specialty centers from 09/2019-12/2020. Incidence rates were calculated per 100 person years (py). Using longitudinal mixed models, we analyzed risk factors associated with sexually transmitted infections (STIs). 4620 PrEP users were included: 99.2% male, median age 38 years (IQR 32-45), 98.6% men who have sex with men (MSM). The median duration of PrEP exposure was 451 days (IQR 357-488), totaling 5132 py. Four HIV infections were diagnosed, incidence rate 0,078/100py (95% CI 0.029-0.208). For two, suboptimal adherence was reported and in the third case, suboptimal adherence and resistance to emtricitabine were observed. One infection was likely acquired before PrEP start. Incidence rates were 21.6/100py for chlamydia, 23.7/100py for gonorrhea, 10.1/100py for syphilis and 55.4/100py for any STI and decreased significantly during the observation period. 65.5% of syphilis, 55.6% of chlamydia and 50.1% of gonorrhea cases were detected by screening of asymptomatic individuals. In a multivariable analysis among MSM younger age, PrEP start before health insurance coverage and daily PrEP were associated with greater risk for chlamydia/gonorrhea. Symptom triggered testing and a history of STI were associated with a higher risk for chlamydia/gonorrhea and syphilis. A significantly lower risk for chlamydia/gonorrhea and syphilis was found for observations during the COVID-19 pandemic period. We found that HIV-PrEP is almost exclusively used by MSM in Germany. A very low incidence of HIV infection and decreasing incidence rates of STIs were found in this cohort of PrEP users. The results were influenced by the SARS-CoV-2 pandemic. Rollout of PrEP covered by health insurance should be continued to prevent HIV infections. Increased PrEP availability to people at risk of HIV infection through the elimination of barriers requires further attention. Investigation and monitoring with a longer follow-up would be of value.

Schmidt D ，Kollan C ，Bartmeyer B ，Bremer V ，Schikowski T ，Friebe M ，Schellberg S ，Scholten S ，Bickel M ，Hanhoff N ，Rüsenberg R ，Schewe K ，NEPOS study group ... -  《-》

Sexual network characteristics of men who have sex with men with syphilis and/or gonorrhoea/chlamydia in Lima, Peru: network patterns as roadmaps for STI prevention interventions.

While men who have sex with men (MSM) are disproportionately affected by Peru's overlapping HIV and STI epidemics, there are few data on how partnership-level and network-level factors affect STI transmission in Peru. We explored partnership-level and network-level factors associated with gonorrhoea/chlamydia (Neisseria gonorrhoeae and/or Chlamydia trachomatis (NG/CT)) and/or syphilis infection among MSM in Peru. We present the results of a cross-sectional secondary analysis of MSM (n=898) tested for syphilis and NG/CT infection as part of the screening process for two STI control trials in Lima, Peru. Participants completed questionnaires on demographics, sexual identity and role, characteristics of their three most recent sexual partners (partner sexual orientation, gender, role, partnership type, partner-specific sexual acts) and 30-day sexual network characteristics (number of sexual partners, partnership types, frequency of anal/vaginal intercourse). Participants were tested for syphilis and urethral, rectal and oropharyngeal NG/CT. Differences in network characteristics were analysed with χ2 and Kruskal-Wallis tests. Approximately 38.9% of participants had a new STI diagnosis (syphilis (rapid plasma reagin ≥16): 10.6%; NG/CT: 22.9%; syphilis-NG/CT coinfection: 5.4%). Condomless anal intercourse (CAI) was not significantly associated with an STI diagnosis. Gay-identified participants with exclusively homosexual networks had a higher prevalence of STIs (47.4%) than gay-identified MSM with only heterosexual/bisexual partners (34.6%, p=0.04), despite reporting fewer sexual partners (any partners: 2, 1-4 vs 3, 2-6; p=0.001; casual partners: 1, 0-3 vs 2, 1-4; p=0.001) and more stable partnerships (1, 0-1 vs 0, 0-1; p=0.003) in the last month. Network size and the number of casual sexual partners were associated with NG/CT infection among MSM in Peru. Despite reporting fewer sexual risk behaviours (smaller network size, more stable partnerships, less CAI), MSM with homosexual-only sexual networks had a higher prevalence of NG/CT and syphilis. These findings suggest network composition among MSM in Peru plays an important role in the risk for STI acquisition.

Blair C ，Passaro RC ，Segura ER ，Lake JE ，Perez-Brumer AG ，Sanchez J ，Lama JR ，Clark JL ... -  《-》

HIV pre-exposure prophylaxis and diagnoses of sexually transmitted infections - observational data from German checkpoints, 01/2019-08/2021.

The impact of starting HIV pre-exposure prophylaxis (PrEP) on diagnoses of sexually transmitted infections (STI) remains unclear. We used data from German HIV/STI Checkpoints collected from 01/2019 to 08/2021 to determine the impact of PrEP use on syphilis, gonorrhoea and chlamydia diagnoses. We used self-reported data on demographics, sexual behaviour, testing and PrEP use, as well as lab-confirmed diagnoses from visits to HIV/STI Checkpoints in Germany. PrEP use was categorized as (1) never used; (2) intention to use; (3) former use; (4) current on-demand use; (5) daily use. In multivariate regression analyses (MRA) with gonorrhoea, chlamydia, and syphilis diagnoses as outcomes, we controlled for age, number of sexual partners, number of condomless anal intercourse (CAI) partners in the last six months, and testing recency. For the analysis, we included 9,219 visits for gonorrhoea and chlamydia testing and 11,199 visits for syphilis testing conducted at checkpoints from 01/2019 to 08/2021. MRA identified age (aOR 0.98; 95%CI 0.97-0.99), number of sexual partners in the past six months (aOR 4.90; 95%CI 2.53-9.52 for 11 + partners), and use of chemsex substances (aOR 1.62; 95%CI 1.32-2.00) as risk factors for gonorrhoea, while age (aOR 0.99; 95%CI 0.98-1.00), number of CAI partners (aOR 3.19; 95%CI 2.32-4.41 for 5 + partners), partner sorting (aOR 1.30; 95%CI 1.09-1.54), and use of chemsex substances (aOR 1.29; 95%CI 1.05-1.59) were risk factors for chlamydia infections. For syphilis, the number of CAI partners (aOR 3.19; 95%CI 1.60-6.34 for 5 + partners) was found to be the only significant risk factor. There was a strong association between PrEP use and the number of sexual partners (≤ 5 vs.>5: aOR 3.58; 95%CI 2.15-5.97 for daily PrEP use), the number of CAI partners in the past six months (≤ 1 vs.>1: aOR 3.70; 95%CI 2.15-6.37 for daily PrEP use), and the number of STI tests performed (suggesting higher testing frequency). Both outcomes were also related to partner sorting, chemsex, and selling sex. Checkpoint visits reporting current PrEP use or intention to start PrEP correlated with eligibility criteria for PrEP, i.e. high partner numbers, inconsistent condom use during anal intercourse, and use of chemsex drugs. Use of HIV-specific prevention methods such as HIV serosorting, PrEP sorting, and viral load sorting was reported more frequently. (Daily) PrEP use was an independent risk factor for a chlamydia diagnosis only.

Marcus U ，Schink SB ，Weber C 《BMC PUBLIC HEALTH》