Incidence of Gonorrhea and Chlamydia Following Human Immunodeficiency Virus Preexposure Prophylaxis Among Men Who Have Sex With Men: A Modeling Study

Expanding access to STI care with free of charge, convenient services in sexual health walk-in clinics

Background: Sexually transmitted infections (STIs) are a long-standing public health issue with increasing incidence in recent years even though most STIs can be effectively treated or even cured with inexpensive medications.Purpose/Design: In this manuscript, we discuss factors that contribute with this concerning scenario, including modifications in the model of STI care in the United States; barriers for diagnosis and treatment; and scarcity of targeted STI prevention messages. We then describe the approach adopted by AIDS Healthcare Foundation to mitigate STI trends, with a focus on sexual health Wellness Centers.Results: The main characteristics of this program include free and convenient services with large volume capacity, sex-positive culture, advertisement of available resources, and accessibility to key populations at higher risk for STI acquisition.Conclusions: This experience could be adapted and expanded to other settings, supporting the public health mission of controlling the spread and detrimental outcomes of STIs.

iPARTY study: Increasing pre-exposure prophylaxis access and reach via telehealth for young men who have sex with men in Singapore 2022-2023

Introduction

Although pre-exposure prophylaxis (PrEP) has been available in Singapore since 2016, its uptake among gay, bisexual and other men-who-have-sex-with-men (GBMSM) is low. The iPARTY study was established to evaluate the acceptability and feasibility of PrEP and a PrEP teleconsultation service for young GBMSM aged 18 to 29 years.

Method

A total of 53 young GBMSM were enrolled in the iPARTY study. They had a total of 5 in-person consultations and teleconsultations, at 12-week intervals. Laboratory tests and quarterly baseline surveys were performed to assess PrEP adherence, sexual behaviour, and incidence of human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs).

Results

Thirty-five participants completed the entire 12-month follow-up. Most participants had positive experiences with PrEP teleconsultations. There was a statistically significant fall in participants' aggregate Patient Health Questionnaire-9 scores throughout the study. Self-reported PrEP adherence decreased over the course of the study, denoting improved mental health. Although self-reported condom use for anal intercourse and participants' risk perception of HIV decreased after PrEP adoption, there was no statisti-cally significant increase in STI incidence.

Conclusion

This pilot project has shown that PrEP services provide an opportunity for YMSM to access sexual health testing, treatment and counselling, and may even have tangible benefits on the mental health of this population. Teleconsultation is shown to be a suitable platform for the delivery of such services. Collaborative initiatives are crucial to further enhance the affordability and accessibility of PrEP in Singapore, and to improve patient adherence.

Recurrence of sexually transmitted infections is commonly found in a subpopulation of Austrian users of HIV pre-exposure prophylaxis

BACKGROUND

In recent years there has been an increase in the diagnoses of sexually transmitted infections (STI) among men who have sex with men (MSM) using human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP); however, data on PrEP users in Austria are limited.

PATIENTS, MATERIAL AND METHODS

In June 2020, we initiated a prospective observational cohort study at Vienna General Hospital including PrEP users from Vienna. Participants underwent STI testing quarterly and provided behavioral information using a questionnaire.

RESULTS

Between June 2020 and December 2023 a total of 360 individuals (99% MSM) were enrolled comprising 379 person-years of follow-up. We identified 276 STIs in 154 individuals, of which 23% (36/154) were symptomatic. The incidence rates per 100 person-years were 29.9 (95% confidence interval, CI 24.3-35.3 per 100 person-years) for gonorrhea, 22.7 (95% CI 17.9-27.5 per 100 person-years) for chlamydia and 9.8 (95% CI 6.6-12.9 per 100 person-years) for syphilis. Extragenital infections accounted for 95% (97/102) of gonorrhea and 81% (65/80) of chlamydia cases. A case of HIV infection was recorded in a 20-year-old male with inconsistent PrEP use. Participants with one or more reinfection (18%; 65/360) accounted for 68% (187/276) of all STIs. Sexualized drug use (Chemsex) was reported by 44% (157/360) of participants and was significantly associated with higher rates of gonorrhea (38% vs. 21%, p < 0.001) and syphilis (17% vs. 5%, p < 0.001) but not chlamydia (26% vs. 19%, p = 0.118).

CONCLUSION

Throughout the study, 43% of participants experienced a bacterial STI, which was mostly asymptomatic and at extragenital sites. Chemsex was commonly reported and identified as a predictor for STI reinfection, underlining the importance of harm reduction strategies in Austrian STI prevention.

Routine Testing for Chlamydia and Gonorrhea in an HIV Pre-Exposure Prophylaxis Program in Hanoi, Vietnam: Implications for Low- and Middle-Income Countries

Objectives

To assess the prevalence, anatomical distribution, and correlates of Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) infections within an HIV pre-exposure prophylaxis (PrEP) program in Hanoi, Vietnam.

Design

Cross-sectional, observational study.

Methods

Between January-December 2022, HIV PrEP program clients who were male at birth, ≥16 years old, reported ≥1 male sex partner in the prior 12 months, were enrolled. A questionnaire collected sociodemographics, sexual behaviors, and clinical data. CT/NG testing was performed on self-collected urine, rectal, and pharyngeal specimens. Multivariate logistic regression was used to identify factors associated with infections.

Results

Among 529 participants, the prevalence of CT or NG was 28.9% (153/529). The prevalence of NG was 14.4% (76/529) and highest for pharyngeal infections (11.7%; 62/528), while for CT, the prevalence was 20.4% (108/529) and highest for rectal infections (15.0%; 74/493). Symptoms in the prior week were reported by 45.8% (70/153) of those with CT or NG infections. Among asymptomatic participants, there was a low prevalence of urethral CT (3.1%; 14/457) and NG (0.9%; 4/457). Condomless anal sex (aOR= 1.98; 95% CI: 1.27, 3.09) and sexualized drug use in the prior 6 months (aOR= 1.71; 95% CI: 1.09, 2.69) were associated with CT/NG infections.

Conclusions

The study found a high prevalence of CT/NG infections, particularly pharyngeal and rectal infections, within an HIV PrEP program in Hanoi, Vietnam. The findings suggest testing for urethral infections among asymptomatic individuals is of limited value. Further research is needed for STI prevention strategies and updated guidelines for CT/NG screening in HIV PrEP programs in low- and middle-income countries.

Factors associated with bacterial sexually transmitted infection screening uptake and diagnosis among men who have sex with men in France

BACKGROUND

The prevalence of syphilis, Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG) in men who have sex with men (MSM) is very high. As these bacterial sexually transmitted infections (bSTIs) are frequently asymptomatic, they are often undiagnosed and therefore untreated. We aimed to characterize the profile of MSM who reported bSTI screening and diagnosis in the previous 12 months, and to identify the factors associated with a diagnosis of a bSTI among MSM in France.

METHODS

We used data from Enquête Rapport au Sexe (ERAS), a large French national anonymous cross-sectional online survey among MSM conducted from 26 February to 11 April 2021. After comparing MSM screened and diagnosed in the previous year with those who were not, a binary logistic regression model was used to compare MSM diagnosed with at least one bSTI with those who were not.

RESULTS

Of the 13 300 survey respondents, 6 263 (47.1%) MSM reported screening for at least one bSTI in the previous 12 months. Of these, 1 060 (16.9%) were diagnosed for at least one bSTI during their most recent screening. Specifically, 446 (7.1%) MSM were diagnosed with NG, 427 (6.8%) with CT, and 402 (6.4%) for syphilis. The following self-reported factors were associated with a greater likelihood of bSTI diagnosis: younger age, a lower educational level, frequenting MSM meeting places, not currently using pre-exposure prophylaxis (PrEP) but willing to take preventive treatment against bSTIs (reference group: not using PrEP and not willing to take preventive treatment against bSTIs), low health literacy, more than one sexual male partner, practicing chemsex, and condomless anal intercourse with casual male partners (the latter three factors concerning the previous six months).

CONCLUSIONS

A large proportion of MSM were diagnosed for at least one bSTI. This result provides an insight into bSTI screening uptake and diagnosis among MSM in France, and could inform future decisions about how to plan effective bSTI screening and diagnosis programs for this population.

Impact of Varying Pre-exposure Prophylaxis Programs on HIV and Neisseria gonorrhoeae Transmission Among MSM in the Netherlands: A Modeling Study

BACKGROUND

In 2019, a 5-year pre-exposure prophylaxis (PrEP) program started in the Netherlands, in which up to 8500 men who have sex with men (MSM) can obtain PrEP and 3-monthly consultations with HIV/STI testing.

SETTING

We assessed the impact of the PrEP program on transmission of HIV and Neisseria gonorrhea (NG) among MSM in the Netherlands and examined prospective variations of the program after 2024.

METHODS

We used an agent-based model to estimate the effect of the PrEP program. For hypothetical prospective PrEP programs starting in 2024, we varied the capacity (8,500; 12,000; 16,000 participants) and consultation frequency (3-monthly; 6-monthly; 70% 3-monthly and 30% 6-monthly).

RESULTS

At a capacity of 8,500 participants and 3-monthly consultations, the PrEP program could lead to 3,140 [95% credible interval (95% CrI): 1,780-4,780] and 27,930 (95% CrI: 14,560-46,280) averted HIV and NG infections, requiring 316,050 (95% CrI: 314,120-317,580) consultations. At a capacity of 16,000 participants, the programs with 3-monthly consultations and 6-monthly consultations could lead to comparable number of averted HIV [3,940 (95% CrI: 2,420-5,460), and 3,900 (2,320-5,630) respectively] and NG infections [29,970 (95% CrI: 15,490-50,350), and 29,960 (95% CrI: 13,610-50,620) respectively], while requiring substantially different number of consultations: 589,330 (95% CrI: 586,240-591,160) and 272,590 (95% CrI: 271,770-273,290), respectively.

CONCLUSIONS

Continuation of a PrEP program could lead to a substantial reduction in HIV and NG transmission. More infections could be averted if the number of participants is increased. In turn, the consultation frequency could be reduced without reducing the number of averted infections if capacity is increased.

High cure rates of Mycoplasma genitalium following empiric treatment with azithromycin alongside frequent detection of macrolide resistance in Austria

BACKGROUND

Mycoplasma genitalium (MG) is an emerging sexually transmitted infection, often harboring resistance-associated mutations to azithromycin (AZM). Global surveillance has been mandated to tackle the burden caused by MG, yet no data are available for Austria. Thus, we aimed to investigate the prevalence of MG, disease characteristics, and treatment outcomes at the largest Austrian HIV-and STI clinic.

METHODS

All MG test results at the Medical University of Vienna from 02/2019 to 03/2022 were evaluated. Azithromycin resistance testing was implemented in 03/2021.

RESULTS

Among 2671 MG tests, 199 distinct and mostly asymptomatic (68%; 135/199) MG infections were identified, affecting 10% (178/1775) of all individuals. This study included 83% (1479/1775) men, 53% (940/1775) men who have sex with men (MSM), 31% (540/1754) HIV+, and 15% (267/1775) who were using HIV pre-exposure prophylaxis (PrEP). In logistic regression analysis, 'MSM' (aOR 2.55 (95% CI 1.65-3.92)), 'use of PrEP' (aOR 2.29 (95% CI 1.58-3.32)), and 'history of syphilis' (aOR 1.57 (95% CI 1.01-2.24) were independent predictors for MG infections. Eighty-nine percent (178/199) received treatment: 11% (21/178) doxycycline (2 weeks), 52% (92/178) AZM (5 days), and 37% ( 65/178) moxifloxacin (7-10 days) and 60% (106/178) had follow-up data available showing negative tests in 63% (5/8), 76% (44/58) and 85% (34/40), respectively. AZM resistance analysis was available for 57% (114/199)) and detected in 68% (78/114). Resistance-guided therapy achieved a cure in 87% (53/61), yet, empiric AZM-treatment (prior to 03/2021) cleared 68% (26/38).

CONCLUSIONS

Mycoplasma genitalium was readily detected in this Austrian observational study, affected predominantly MSM and often presented as asymptomatic disease. We observed a worryingly high prevalence of AZM resistance mutations; however, empiric AZM treatment cleared twice as many MG infections as expected.

Routine Data Analysis of HIV Pre-Exposure Prophylaxis Use and Rates of Sexually Transmitted Infections Since Coverage of HIV Pre-Exposure Prophylaxis by the Statutory Health Insurance in Germany

Human immunodeficiency virus pre-exposure prophylaxis (PrEP) is considered as an effective protection against a human immunodeficiency virus (HIV) infection. However, it is still unclear, how PrEP use is associated with the incidence of sexually transmitted infections (STI) other than HIV. PrEP became reimbursable in Germany from September 1, 2019 for persons with statutory health insurance (SHI). With the EvE-PrEP study, the Federal Ministry of Health commissioned the evaluation of the effects of the new reimbursement situation in Germany. In the presented module of the EvE-PrEP study, routine data from three large German SHI funds were analyzed in anonymized form for the period January 1, 2019 to March 31, 2020. Data were analyzed regarding: Characteristics and adherence of PrEP users, treatment success of PrEP, and changes in STI incidence rates before and since PrEP use. The cooperating SHI funds collectively covered about 52% of the overall population in Germany in 2019. A total of 7102 persons with PrEP use were included into the analysis. These were predominantly male (99%), on average 37.4 years old and a high proportion of persons lived in large cities. The average quotient of PrEP daily defined doses and assumed days on PrEP was 87%. The average STI rates normalized per 100 person-years at individual level pre PrEP did not statistically significant differ compared to since PrEP (chlamydia: 17.5 vs. 17.6, gonococcal infection: 29.1 vs. 30.7, and syphilis: 14.6 vs.13.6). A large data set was used to evaluate the introduction of PrEP as a SHI benefit in Germany. A potentially suspected increase in bacterial STI incidence rates was not found. A rather high average adherence rate was observed. The very high proportion of men and people from the largest German cities among PrEP users is striking. These results could indicate barriers to PrEP access for people at risk of HIV, especially if they are women or people living in less urban areas.

Missed opportunities for guidance on sexually transmitted infection services: a global review of national HIV PrEP guidance

OBJECTIVES

People who use or would benefit from pre-exposure prophylaxis (PrEP) for HIV infection are disproportionately affected by sexually transmitted infections (STIs). Integrating STI services when offering PrEP fosters synergies and efficiencies in response to HIV/STI and promotes people-centred care. Including guidance on STI interventions for people on PrEP may facilitate implementation and uptake. We conducted a global review of national PrEP guidance documents and analysed the inclusion of recommendations for the provision of STI services by country level of income.

METHODS

We searched national PrEP guidance documents published by WHO Member States through the WHO, the Joint United Nations Programme on HIV/AIDS (UNAIDS) databases, the PrEPWatch repository and Google. Information on a range of STI-related interventions was extracted from documents available by October 2023.

RESULTS

Of the 113 national PrEP guidance documents retrieved, STIs were mentioned in 77% (90/117). Viral hepatitis B testing and vaccination were recommended by most high-income countries (HICs) and low-income and middle-income countries (LMICs). Recommendation for syphilis testing was prominent in HICs (91%) and moderately noted in LMICs (68%). Gonorrhoea and chlamydia testing was recommended frequently in HICs (88%) and 42% in LMICs. However, the review noted that, to a much lesser extent, specific type of testing for these pathogens was mentioned. Recommendation for quarterly STI testing for syphilis, gonorrhoea and chlamydia was ubiquitous, while the need to offer STI partner services was rarely mentioned.

CONCLUSIONS

PrEP services offer an opportunity for improved and expanded STI services, increasing person-centred care and addressing STI epidemics alongside HIV. Our review highlights the strengths and gaps in incorporating critical STI interventions into national PrEP normative guidance. Addressing these gaps through a stepwise approach and increasing targeted testing and partner services can help improve quality of care and support an effective response to HIV and other STIs.

Epidemiological impact of Neisseria gonorrhoeae and Chlamydia trachomatis screening in men having sex with men: a modelling study

OBJECTIVES

The impact of the systematic screening of Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) in men having sex with men (MSM) on these pathogens' epidemiology remains unclear. We conducted a modelling study to analyse this impact in French MSM.

METHODS

We modelled NG and CT transmission using a site-specific deterministic compartmental model. We calibrated NG and CT prevalence at baseline using results from MSM enrolled in the Dat'AIDS cohort. The baseline scenario was based on 1 million MSM, 40 000 of whom were tested every 90 days and 960 000 every 200 days. Incidence rate ratios (IRRs) at steady state were simulated for NG, CT, NG and/or CT infections, for different combinations of tested sites, testing frequency and numbers of frequently tested patients.

RESULTS

The observed prevalence rate was 11.0%, 10.5% and 19.1% for NG, CT and NG and/or CT infections. The baseline incidence rate was estimated at 138.2 per year per 100 individuals (/100PY), 86.8/100PY and 225.0/100PY for NG, CT and NG and/or CT infections. Systematically testing anal, pharyngeal and urethral sites at the same time reduced incidence by 14%, 23% and 18% (IRR: 0.86, 0.77 and 0.82) for NG, CT and NG and/or CT infections. Reducing the screening interval to 60 days in frequently tested patients reduced incidence by 20%, 29% and 24% (IRR: 0.80, 0.71 and 0.76) for NG, CT and NG and/or CT infections. Increasing the number of frequently tested patients to 200 000 reduced incidence by 29%, 40% and 33% (IRR: 0.71, 0.60 and 0.67) for NG, CT and NG and/or CT infections. No realistic scenario could decrease pathogens' incidence by more than 50%.

CONCLUSIONS

To curb the epidemic of NG and CT in MSM, it would not only be necessary to drastically increase screening, but also to add other combined interventions.

Risk Compensation After Initiation of Daily Oral Pre-exposure Prophylaxis Among Sexual and Gender Minorities in Nigeria

Pre-exposure prophylaxis (PrEP) use may be associated with risk compensation. We enrolled and provided PreP to sexual and gender minorities (SGM) in Abuja, Nigeria between April 2018 and May 2019. Behavioral information and samples for urogenital and anorectal Chlamydia trachomatis and Neisseria gonorrhoeae sexually transmitted infections (STIs) were collected at baseline. Blood samples for PrEP assay and self-reported adherence were collected at three-monthly follow-up visits. STIs were detected using Aptima Combo2 assay. We estimated the odds ratios (ORs) of PCR-diagnosed bacterial STIs and self-reported behavioral outcomes (condomless anal intercourse [CAI] and concurrent sexual relationships) with conditional logistic regression. Of 400 SGM who initiated PrEP, 206 were eligible for analysis, and had a median age of 24 years (IQR 22-27). In multivariable analysis, participants in the PrEP period had decreased odds of CAI (adjusted OR: 0.49, 95% CI 0.28, 0.84). PrEP use was not associated with risk compensation.

Slovenia's national HIV PrEP programme: Evaluation of real-world implementation

BACKGROUND

The aim of our study was to evaluate real-world implementation of Slovenia's national HIV PrEP programme, which is fully covered by our national health insurance.

METHODS

In retrospective cohort study we analysed the data from all men who have sex with men (MSM) who were enrolled in PrEP programme of our clinic between 1 January 2022 and 31 December 2022.

RESULTS

A total of 190 MSM with an average age of 36.7 years were included in our analysis. 151 (79.5%) decided for event-driven PrEP and 39 (20.5%) opted for daily PrEP. Self-reported adherence was 95%. Among eligibility criteria, unprotected sex was the most common one, followed by one or more STIs in the past, use of chemsex and use of HIV post-exposure prophylaxis in the past. No new cases of HIV infection and no significant deterioration of kidney or liver function were observed during the follow-up. Sixty-seven episodes of STIs were diagnosed and treated. Gonorrhea (32), chlamydia (14), and Mpox (10) were the most common ones.

CONCLUSIONS

PrEP was successfully implemented into everyday clinical practice, proving to be both safe and effective. High number of diagnosed STIs suggests that the PrEP programme, combined with STI screening and vaccination, provides a strong public health impact among MSM in Slovenia.

Effect of mass treatment on the long-term prevalence of gonorrhoea, chlamydia and syphilis-a systematic review

BACKGROUND

Selective mass treatment of STIs may lead to a durable reduction in the prevalence of STIs or a temporary reduction associated with an increased probability of antimicrobial resistance emerging.

METHODS

We searched PubMed and Google Scholar for studies evaluating the impact of mass STI treatment on the long-term prevalence of chlamydia, gonorrhoea, syphilis and chancroid. The primary outcomes were the long term (≥3 months post the intervention) impact of the intervention on prevalence/incidence of the STI and on antimicrobial resistance.

RESULTS

Our search yielded 269 studies, of which 4 met the inclusion criteria. With the exception of the Carletonville study, where this was not assessed, three of the four studies found that intensive STI treatment was associated with a reduced prevalence of the targeted STI during or immediately after the intervention. In all four studies, there was no evidence that the intense treatment had a long-term effect on prevalence. In the only study where this was assessed, the intensive use of penicillin to reduce gonococcal prevalence was associated with the emergence of reduced susceptibility to penicillin in N. gonorrhoeae.

CONCLUSION

The available evidence suggests that mass treatment of chlamydia, gonorrhoea and syphilis in high prevalence populations is only associated with a temporary reduction in the prevalence of these infections and may select for antimicrobial resistance.

Management of Neisseria gonorrhoeae infection: from drug resistance to drug repurposing

INTRODUCTION

Neisseria gonorrhoeae is a common sexually transmitted disease connected with extensive drug resistance to many antibiotics. Presently, only expanded spectrum cephalosporins (ceftriaxone and cefixime) and azithromycin remain useful for its management.

AREAS COVERED

New chemotypes for the classical antibiotic drug target gyrase/topoisomerase IV afforded inhibitors with potent binding to these enzymes, with an inhibition mechanism distinct from that of fluoroquinolones, and thus less prone to mutations. The α-carbonic anhydrase from the genome of this bacterium (NgCAα) was also validated as an antibacterial target.

EXPERT OPINION

By exploiting different subunits from the gyrase/topoisomerase IV as well as new chemotypes, two new antibiotics reached Phase II/III clinical trials, zoliflodacin and gepotidacin. They possess a novel inhibition mechanism, binding in distinct parts of the enzyme compared to the fluoroquinolones. Other chemotypes with inhibitory activity in these enzymes were also reported. NgCAα inhibitors belonging to a variety of classes were obtained, with several sulfonamides showing MIC values in the range of 0.25-4 µg/mL and significant activity in animal models of this infection. Acetazolamide and similar CA inhibitors might thus be repurposed as antiinfectives. The scientific/patent literature has been searched for on PubMed, ScienceDirect, Espacenet, and PatentGuru, from 2016 to 2024.

Estimating Partnership Duration among MSM in Belgium-A Modeling Study

Mathematical modeling is widely used for describing infection transmission and evaluating interventions. The lack of reliable social parameters in the literature has been mentioned by many modeling studies, leading to limitations in the validity and interpretation of the results. Using data from the European MSM Internet survey 2017, we developed a network model to describe sex acts among MSM in Belgium. The model simulates daily sex acts among steady, persistent casual and one-off partners in a population of 10,000 MSM, grouped as low- or high-activity by using three different definitions. Model calibration was used to estimate partnership duration and homophily rates to match the distribution of cumulative sex partners over 12 months. We estimated an average duration between 1065 and 1409 days for steady partnerships, 4-6 and 251-299 days for assortative high- and low-activity individuals and 8-13 days for disassortative persistent casual partnerships, respectively, varying across the three definitions. High-quality data on social network and behavioral parameters are scarce in the literature. Our study addresses this lack of information by providing a method to estimate crucial parameters for network specification.

Effect of screening for Neisseria gonorrhoeae and Chlamydia trachomatis on incidence of these infections in men who have sex with men and transgender women taking HIV pre-exposure prophylaxis (the Gonoscreen study): results from a randomised, multicentre, controlled trial

BACKGROUND

Guidelines recommend screening for Neisseria gonorrhoeae and Chlamydia trachomatis at three anatomical sites (urethra, anus, and pharynx) every 3 months (3 × 3) in men who have sex with men (MSM) and transgender women taking HIV pre-exposure prophylaxis (PrEP). We present the first randomised controlled trial to compare the effect of screening versus non-screening for N gonorrhoeae and C trachomatis on the incidence of these infections in MSM and transgender women taking PrEP.

METHODS

A multicentre, randomised, controlled trial of 3 × 3 screening for N gonorrhoeae and C trachomatis versus non-screening was done among MSM and transgender women taking PrEP in five HIV reference centers in Belgium. Participants attended the PrEP clinics quarterly for 12 months. N gonorrhoeae and C trachomatis was tested at each visit in both arms, but results were not provided to the non-screening arm, if asymptomatic. The primary outcome was incidence rate of N gonorrhoeae and C trachomatis infections in each arm, assessed in the per-protocol population. Non-inferiority of the non-screening arm was proven if the upper limit of the 95% CI of the incidence rate ratio (IRR) was lower than 1·25. This trial is registered with ClinicalTrials.gov, NCT04269434, and is completed.

FINDINGS

Between Sept 21, 2020, and June 4, 2021, 506 participants were randomly assigned to the 3 × 3 screening arm and 508 to the non-screening arm. The overall incidence rate of N gonorrhoeae and C trachomatis was 0·155 cases per 100 person-days (95% CI 0·128-0·186) in the 3 × 3 screening arm and 0·205 (95% CI 0·171-0·246) in the non-screening arm. The incidence rate was significantly higher in the non-screening arm (IRR 1·318, 95% CI 1·068-1·627). Participants in the non-screening arm had a higher incidence of C trachomatis infections and symptomatic C trachomatis infections. There were no significant differences in N gonorrhoeae infections. Participants in the non-screening arm consumed significantly fewer antimicrobial drugs. No serious adverse events were reported.

INTERPRETATION

We failed to show that non-screening for N gonorrhoeae and C trachomatis is non-inferior to 3 × 3 screening in MSM and transgender women taking PrEP in Belgium. However, screening was associated with higher antibiotic consumption and had no effect on the incidence of N gonorrhoeae. Further research is needed to assess the benefits and harms of N gonorrhoeae and C trachomatis screening in this population.

FUNDING

Belgian Health Care Knowledge Centre.

Lymphogranuloma venereum verläuft häufig asymptomatisch bei Männern, die Sex mit Männern haben, in Österreich

Hintergrund und Ziele

Lymphogranuloma venereum (LGV) ist eine sexuell übertragene Erkrankung verursacht durch Chlamydia trachomatis (CT), Serovar L1–L3. Eine Zunahme von LGV ist vorwiegend bei Männern, die Sex mit Männern haben (MSM), beobachtet worden. Die Unterscheidung zwischen LGV und Nicht‐LGV‐Serovaren hat therapeutische Konsequenzen, daher wurden Prävalenz und Charakteristika von LGV innerhalb aller CT‐Infektionen untersucht.

Patienten und Methodik

Alle CT‐positiven Befunde, erhoben an den vier größten österreichischen HIV‐ und STI‐Kliniken von 04/2014–12/2021, wurden hinsichtlich Charakteristika der Erkrankung und Demographie der Patienten ausgewertet.

Ergebnisse

Insgesamt wurden n = 2083 CT‐Infektionen bei n = 1479 Personen dokumentiert. Das mediane Alter betrug 31,4 Jahre, 81% waren männlich, 59% MSM, 44% HIV‐positiv, 13% nutzten HIV‐Prä‐Expositionsprophylaxe. Serovaranalysen waren bei 61% (1258/2083) verfügbar, wobei L1–L3 in 15% (192/1258) aller Fälle nachgewiesen wurde. Bei MSM mit rektaler CT‐Infektion waren 23% (101/439) LGV. LGV‐Fälle verglichen mit CT‐Infektionen traten vermehrt bei MSM (92% [177/192] vs. 62% [1179/1891], p < 0,001), HIV‐Positivität (64% [116/180] vs. 46% [631/1376]; p < 0,001) und konkomitanter Syphilisinfektion (18% [32/180] vs. 7% [52/749]; p < 0,001) auf. LGV‐Infektionen verliefen zumeist asymptomatisch (45% [87/192]), gefolgt von Proktitis (38% [72/192]).

Schlussfolgerungen

Lymphogranuloma venereum machte 23% der rektalen CT‐Infektionen bei MSM aus und 45% aller LGV‐Fälle waren asymptomatisch. Bei fehlender CT‐Serovar‐Analyse sollte in Risikopopulationen eine erhöhte LGV‐Prävalenz in Betracht gezogen und bei der empirischen Therapiedauer berücksichtigt werden.

A Practical Approach to Sexually Transmitted Infection Screening for the Primary Care Clinician

Sexually transmitted infections (STIs) are commonly encountered in primary care. The Centers for Disease Control and Prevention and the US Preventive Services Task Force have both issued guidelines about screening for chlamydia, gonorrhea, syphilis, and HIV. By eliciting a sexual history, understanding their patients' anatomy, and considering factors which may increase the likelihood of STIs and their sequelae, clinicians can implement a practical, evidence-based approach to STI screening.

Asymptomatic lymphogranuloma venereum is commonly found among men who have sex with men in Austria

BACKGROUND AND OBJECTIVES

Serovar L1-L3 of Chlamydia trachomatis (CT) causes lymphogranuloma venereum (LGV). A surge in LGV-cases has been observed among HIV-positive men who have sex with men (MSM). Discrimination between LGV and non-LGV is pivotal since it has major treatment implications. Here, we aimed to determine the prevalence and characteristics of LGV among CT-infections.

PATIENTS AND METHODS

All CT-positive results from 04/2014-12/2021 at the four largest Austrian HIV and STI clinics were evaluated. Disease characteristics and patient demographics were analyzed.

RESULTS

Overall, n  =  2,083 infections of CT were documented in n  =  1,479 individual patients: median age was 31.4 years, 81% were male, 59% MSM, 44% HIV-positive, 13% on HIV pre-exposure-prophylaxis. Available serovar analyses (61% [1,258/2,083]) showed L1-L3 in 15% (192/1,258). Considering only MSM with rectal CT-infection, LGV accounted for 23% (101/439). Cases of LGV vs. other CT-infections were primarily MSM (92% [177/192] vs. 62% [1,179/1,891], p < 0.001), more often HIV-positive (64% [116/180] vs. 46% [631/1,376]; p < 0.001) and had frequently concomitant syphilis infection (18% [32/180] vs. 7% [52/749]; p < 0.001). LGV commonly manifested as proctitis (38% [72/192]) whereas 45% (87/192) were asymptomatic.

CONCLUSIONS

Lymphogranuloma venereum accounted for 23% of rectal CT-infections in MSM. Furthermore, 45% of all LGV-cases were asymptomatic. In the absence of CT-serovar analysis, a high LGV prevalence should be considered in risk-populations and guide empiric treatment selection.

Patterns of Chlamydia trachomatis and Neisseria gonorrhoeae in different anatomical sites among Pre-Exposure Prophylaxis (PrEP) users in Brazil

BACKGROUND

The presence of untreated sexually transmitted infections (STIs) significantly increases the chance of acquiring HIV. In Brazil, testing for Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) among Pre-Exposure Prophylaxis (PrEP) users is insufficient, and syndromic treatment is a priority in clinical practice. Multi-site testing for CT/NG improves thescreening of asymptomatic cases and ensures timely treatment. Therefore, it is essential for HIV prevention. This study aims to test the importance of two-site testing for better screening of these pathogens and to determine whether the presence of symptoms is an indicator of CT/NG infection.

METHODS

This is a cross-sectional study carried out in four public infectious diseases clinics in São Paulo State, Brazil between January of 2022 and March of 2023. All participants had an anal swab and a first-pass or mid-stream urine collected for CT/NG analysis by Polymerase chain reaction (PCR). Data about sociodemographic, sexual behavioural and clinical aspects were collected. Pathway analysis was used to examine the direct and indirect relationships between variables according to the theoretical model.

RESULTS

We screened 171 PrEP users which had two samples collected, resulting in 342 samples. Comparing the anatomic sites, the urine samples showed lower sensitivity for CT and NG than anal samples. Gonorrhoea was directly linked to lower age (β= -0.161, p = 0.001). Time of PrEP use was directly associated with CT infection (β = 0.202; p = 0.042) and inversely associated with dysuria (β= -0.121, p = 0.009). Lower occurrence of yellow-green secretion was linked to detection of CT (β= -0.089, p = 0.005) and NG (β= -0.048, p = 0.002) infections. Foul-smelling discharge was directly associated with CT (β = 0.275, p = 0.004) and NG (β = 0.295, p = 0.037) infection.

CONCLUSION

The symptoms are a bad indicator of CT and NG infection, and the screening must be done in more than one site since most of the positive results would be missed if only urines were tested. In the case of testing only one anatomical site, specifically the urethra, the CT/NG incidence and prevalence would be underestimated. The two-sites testing improves detection rates of CT/NG, and PrEP follow-up benefits people offering STI testing.

Modelling the impact of vaccination and sexual behaviour adaptations on mpox cases in the USA during the 2022 outbreak

BACKGROUND

The 2022 mpox outbreak has infected over 30 000 people in the USA, with cases declining since mid-August. Infections were commonly associated with sexual contact between men. Interventions to mitigate the outbreak included vaccination and a reduction in sexual partnerships. Understanding the contributions of these interventions to decreasing cases can inform future public health efforts.

METHODS

We fit a dynamic network transmission model to mpox cases reported by Washington DC through 10 January 2023. This model incorporated both vaccine administration data and reported reductions in sexual partner acquisition by gay, bisexual or other men who have sex with men (MSM). The model output consisted of daily cases over time with or without vaccination and/or behavioural adaptation.

RESULTS

We found that initial declines in cases were likely caused by behavioural adaptations. One year into the outbreak, vaccination and behavioural adaptation together prevented an estimated 84% (IQR 67% to 91%) of cases. Vaccination alone averted 79% (IQR 64% to 88%) of cases and behavioural adaptation alone averted 25% (IQR 10% to 42%) of cases. We further found that in the absence of vaccination, behavioural adaptation would have reduced the number of cases, but would have prolonged the outbreak.

CONCLUSIONS

We found that initial declines in cases were likely caused by behavioural adaptation, but vaccination averted more cases overall and was key to hastening outbreak conclusion. Overall, this indicates that outreach to encourage individuals to protect themselves from infection was vital in the early stages of the mpox outbreak, but that combination with a robust vaccination programme hastened outbreak conclusion.

Sexually Transmitted Infection Prevention Perspectives in Black Men Who Have Sex With Men Taking Preexposure Prophylaxis in New Orleans

INTRODUCTION

Profound sexual health disparities exist for Black men who have sex with men (MSM) in the US South, including a high prevalence of sexually transmitted infections (STIs). Sexually transmitted infection prevention strategies beyond condoms are needed for Black MSM taking preexposure prophylaxis (PrEP).

METHODS

We conducted in-depth interviews with Black MSM taking PrEP in New Orleans, Louisiana. Informed by the Health Belief Model, we asked about participants' perceived susceptibility, severity, and concerns regarding STIs, and perceived benefits of STI prevention. We also asked about willingness to use various STI prevention strategies, including antibiotic prophylaxis. Interviews were audio-recorded and analyzed using applied thematic analysis.

RESULTS

We interviewed 24 Black MSM aged 18 to 36 years; half had a recent STI diagnosis. Most participants were concerned about receiving an STI diagnosis, noting shame or disappointment; physical effects were concerning but infrequently considered. Participants described being less likely to use condoms with routine partners or those taking PrEP. Most reported being willing to engage in each of the 6 prevention strategies discussed.

CONCLUSIONS

Black MSM taking PrEP voiced concern about STIs, and many noted that they infrequently use condoms. They were willing to engage in methods focused on preventing STIs on an individual or population level.

Beyond HIV prevention: Assessment of the benefits of pre-exposure prophylaxis for sexual quality of life

BACKGROUND

Pre-exposure prophylaxis (PrEP) may favor sexual satisfaction by reducing the fear of HIV and promoting less restrictive sexual practices. These benefits may be even higher among PrEP users with mental health issues.

METHODS

We invited adult PrEP users to answer a questionnaire including demographics, questions on the sexual experience compared to the period before PrEP use, and the Hospital Anxiety and Depression Scale. Factors associated with improvements in the sexual experience were investigated using modified Poisson models.

RESULTS

We included 221 participants; most were white males. A large percentage of participants reported improvements in quality of sex after PrEP initiation; the composite outcome "PrEP-associated improvement in the quality of sex" was observed in 92 (42%), whereas the outcome "PrEP-associated improvement in the fear of HIV acquisition" was observed in 120 participants (54%). Demographics and depression/anxiety were not significantly associated with the outcomes.

CONCLUSION

PrEP has positive effects beyond HIV prevention, improving several aspects of sexual quality of life. These benefits are valid incentives for PrEP use and prescription.

Incidence of sexually transmitted infections and association with behavioural factors: Time-to-event analysis of a large pre-exposure prophylaxis (PrEP) cohort

OBJECTIVES

Our objective was to obtain long-term data on the incidence of sexually transmitted infections (STIs) and their association with behavioural factors after widespread pre-exposure prophylaxis (PrEP) implementation.

METHODS

This was a time-to-event analysis of a national PrEP cohort in Switzerland (SwissPrEPared study). Participants were people without HIV interested in taking PrEP with at least two STI screening visits. Primary outcomes were incidence rate of gonorrhoea, chlamydia, and syphilis. The association between behavioural factors and STI diagnosis was expressed using hazard ratios. We adjusted for testing frequency and calendar year.

RESULTS

This analysis included 3907 participants enrolled between April 2019 and April 2022, yielding 3815.7 person-years of follow-up for gonorrhoea (15 134 screenings), 3802.5 for chlamydia (15 141 screenings), and 3858.6 for syphilis (15 001 screenings). The median age was 39 years (interquartile range [IQR] 32-47), 93.8% (n = 3664) identified as men who have sex with men (MSM). The incidence was 22.8 (95% confidence interval [CI] 21.3-24.4) per 100 person-years for gonorrhoea, 26.3 (95% CI 24.7-28.0) for chlamydia, and 4.4 (95% CI 3.8-5.1) for syphilis. Yearly incidence rates decreased between 2019 (all bacterial STIs: 81.6; 95% CI 59.1-109.9) and 2022 (all bacterial STIs: 49.8; 95% CI 44.6-55.3). Participants reporting chemsex substance use were at higher risk of incident STIs, as were those reporting multiple sexual partners. Younger age was associated with a higher risk of gonorrhoea and chlamydia.

CONCLUSIONS

Incidence rates of bacterial STIs decreased over time. Young MSM, those with multiple partners, and those using chemsex substances were at increased risk of STIs.

Frequent screening for asymptomatic chlamydia and gonorrhoea infections in men who have sex with men: time to re-evaluate?

There is increasing debate regarding the harms and benefits of frequent asymptomatic screening for Chlamydia trachomatis and Neisseria gonorrhoeae in men who have sex with men (MSM). One concern is that frequent asymptomatic screening could result in increased antimicrobial resistance in an array of sexually acquired infections and other pathogens, due to selection pressure exerted by frequent broad-spectrum antimicrobial usage within some sexual networks. Here, we outline the harms and benefits of frequent C trachomatis and N gonorrhoeae screening in MSM in high-income settings and propose that screening frequency be reduced. We describe the evidence gaps that should be further explored to better understand the implications of reducing the frequency of asymptomatic C trachomatis and N gonorrhoeae screening in MSM and the surveillance systems that should be in place to prepare for such changes.

Impact of voluntary testing on infectious disease epidemiology: A game theoretic approach

The World Health Organization recommends test-and-treat interventions to curb and even eliminate epidemics of HIV, viral hepatitis, and sexually transmitted infections (e.g., chlamydia, gonorrhea, syphilis and trichomoniasis). Epidemic models show these goals are achievable, provided the participation of individuals in test-and-treat interventions is sufficiently high. We combine epidemic models and game theoretic models to describe individual's decisions to get tested for infectious diseases within certain epidemiological contexts, and, implicitly, their voluntary participation to test-and-treat interventions. We develop three hybrid models, to discuss interventions against HIV, HCV, and sexually transmitted infections, and the potential behavioral response from the target population. Our findings are similar across diseases. Particularly, individuals use three distinct behavioral patterns relative to testing, based on their perceived costs for testing, besides the payoff for discovering their disease status. Firstly, if the cost of testing is too high, then individuals refrain from voluntary testing and get tested only if they are symptomatic. Secondly, if the cost is moderate, some individuals will test voluntarily, starting treatment if needed. Hence, the spread of the disease declines and the disease epidemiology is mitigated. Thirdly, the most beneficial testing behavior takes place as individuals perceive a per-test payoff that surpasses a certain threshold, every time they get tested. Consequently, individuals achieve high voluntary testing rates, which may result in the elimination of the epidemic, albeit on temporary basis. Trials and studies have attained different levels of participation and testing rates. To increase testing rates, they should provide each eligible individual with a payoff, above a given threshold, each time the individual tests voluntarily.

Management of asymptomatic sexually transmitted infections in Europe: towards a differentiated, evidence-based approach

Most sexually transmitted infections (STIs) can be accurately diagnosed and treated during asymptomatic carriage. Widespread screening for these STIs is therefore assumed to be an effective way to reduce their prevalence and associated disease. In this review, we provide evidence that this is the case for HIV and syphilis. However, for other STIs such as Neisseria gonorrhoeae and Chlamydia trachomatis, our review reveals that the evidence that screening reduces infection prevalence and associated disease is weak. There is also growing evidence of harms from screening that might outweigh any benefits. The harms include the increased consumption of antimicrobials that follows frequent screening and increased detection of asymptomatic STIs in key populations, such as men who have sex with men taking HIV pre-exposure prophylaxis, and associated risk of antimicrobial resistance in target and non-target organisms. There may also be psycho-social harm associated with an STI diagnosis. We conclude that in the absence of symptoms, in high STI prevalence populations frequent STI screening should be limited to HIV and syphilis.

Bacterial sexually transmitted infections are concentrated in subpopulations of men who have sex with men using HIV pre-exposure prophylaxis

OBJECTIVE

Studies have shown varying trends in incidence of sexually transmitted infections (STIs) among individuals using HIV pre-exposure prophylaxis (PrEP). Characterization of individuals at increased risk for STIs may offer an opportunity for targeted STI screening.

DESIGN

Group-based trajectory modeling.

METHODS

We screened participants from the AMPrEP demonstration project (2015-2020) for urogenital, anal, and pharyngeal chlamydia and gonorrhea, and syphilis every 3 months and when needed. We identified trajectories of STI incidence within individuals over time and determinants of belonging to a trajectory group. We calculated cumulative proportions of STIs within STI trajectory groups.

RESULTS

Three hundred and sixty-six participants with baseline and at least one screening visit during follow-up were included (median follow-up time = 3.7 years [interquartile range, IQR = 3.5-3.7]). We identified three trajectories of STI incidence: participants with a mean of approximately 0.1 STIs per 3 months ('low overall', 52% of the population), participants with a mean 0.4 STI per 3 months ('medium overall', 43%), and participants with high and fluctuating (between 0.3 and 1 STIs per 3 months) STI incidence ('high and fluctuating', 5%). Participants in the 'low overall' trajectory were significantly older, and reported less chemsex and condomless anal sex with casual partners than participants in the other trajectories. Participants in the 'high and fluctuating' and 'medium overall' groups accounted for respectively 23 and 64% of all STIs observed during follow-up.

CONCLUSIONS

STI incidence was concentrated in subpopulations of PrEP users who were younger, had more chemsex and condomless anal sex. Screening frequency for STIs could be reduced for subpopulations with low risk for incident STIs.

Partnership types and coital frequency as predictors of gonorrhea and chlamydia among young MSM and young transgender women

BACKGROUND

Sexually transmitted infections pose a major public health challenge in the United States and this burden is especially acute in subpopulations like young men who have sex with men (YMSM) and young transgender women (YTW). Yet, the direct behavioral antecedents of these infections are not well understood making it difficult to identify the cause of recent increases in incidence. This study examines how variations in partnership rates and the number of condomless sex acts are associated with STI infections among YMSM-YTW.

METHOD

This study leveraged 3 years of data from a large longitudinal cohort of YMSM-YTW. A series of generalized linear mixed models examined the association between the number of condomless anal sex acts, number of one-time partners, number of casual partners, and number of main partners and chlamydia, gonorrhea, or any STI.

RESULTS

Results indicated the number of casual partners was associated with gonorrhea [aOR = 1.17 (95% CI: 1.08, 1.26)], chlamydia [aOR = 1.12 (95% CI: 1.05, 1.20)], and any STI [aOR = 1.14 (95% CI: 1.08, 1.21)] while the number of one-time partners was only associated with gonorrhea [aOR = 1.13 (95% CI: 1.02, 1.26)]. The number of condomless anal sex acts was not associated with any outcome.

CONCLUSION

These findings suggest the number of casual partners is a consistent predictor of STI infection among YMSM-YTW. This may reflect the quick saturation of risk within partnerships making the number of partners, rather than the number of acts, the more relevant factor for STI risk.

Improving and Extending STERGM Approximations Based on Cross-Sectional Data and Tie Durations

Temporal exponential-family random graph models (TERGMs) are a flexible class of models for network ties that change over time. Separable TERGMs (STERGMs) are a subclass of TERGMs in which the dynamics of tie formation and dissolution can be separated within each discrete time step and may depend on different factors. The Carnegie et al. (2015) approximation improves estimation efficiency for a subclass of STERGMs, allowing them to be reliably estimated from inexpensive cross-sectional study designs. This approximation adapts to cross-sectional data by attempting to construct a STERGM with two specific properties: a cross-sectional equilibrium distribution defined by an exponential-family random graph model (ERGM) for the network structure, and geometric tie duration distributions defined by constant hazards for tie dissolution. In this paper we focus on approaches for improving the behavior of the Carnegie et al. approximation and increasing its scope of application. We begin with Carnegie et al.'s observation that the exact result is tractable when the ERGM is dyad-independent, and then show that taking the sparse limit of the exact result leads to a different approximation than the one they presented. We show that the new approximation outperforms theirs for sparse, dyad-independent models, and observe that the errors tend to increase with the strength of dependence for dyad-dependent models. We then develop theoretical results in the dyad-dependent case, showing that when the ERGM is allowed to have arbitrary dyad-dependent terms and some dyad-dependent constraints, both the old and new approximations are asymptotically exact as the size of the STERGM time step goes to zero. We note that the continuous-time limit of the discrete-time approximations has the desired cross-sectional equilibrium distribution and exponential tie duration distributions with the desired means. We show that our results extend to hypergraphs, and we propose an extension of the Carnegie et al. framework to dissolution hazards that depend on tie age.

Incidence and Prevalence of Hepatitis C Virus Among HIV-Negative Gay and Bisexual Men Using HIV Pre-exposure Prophylaxis (PrEP): A Systematic Review and Meta-analysis

Background

Gay and bisexual men using HIV pre-exposure prophylaxis (PrEP) are at increased risk for sexually transmissible infections. Hepatitis C virus (HCV) risk among PrEP users is less clear. We explored HCV prevalence and incidence among cohorts of gay and bisexual men using PrEP and sources of heterogeneity across studies.

Methods

This was a systematic review and meta-analysis of open-label PrEP studies to April 2022 reporting HCV prevalence at baseline or incidence during follow-up among gay and bisexual men using PrEP. Pooled prevalence and incidence estimates were calculated using random-effects meta-analysis, and subgroup analyses were performed by study- and country-level characteristics, including availability of HCV direct-acting antiviral (DAA) therapy at time of study.

Results

Twenty-four studies from 9 countries were included, with a total sample of 24 733 gay and bisexual men. Pooled HCV antibody baseline prevalence was 0.97% (95% CI, 0.63%-1.31%), and pooled HCV RNA baseline prevalence was 0.38% (95% CI, 0.19%-0.56%). Among 19 studies reporting HCV incidence, incidence ranged from 0.0 to 2.93/100 person-years (py); the pooled estimate was 0.83/100py (95% CI, 0.55-1.11). HCV incidence was higher in 12 studies that began follow-up before broad DAA availability (1.27/100py) than in 8 studies that began follow-up after broad DAA availability (0.34/100py) and higher in studies in Europe compared with North America and Australia.

Conclusions

Early reports of high HCV incidence among PrEP-using cohorts likely reflect enrollment of individuals based on specific risk-based eligibility criteria for smaller studies and enrollment before DAA scale-up. In contexts where both DAAs and PrEP have been implemented at scale, studies report lower HCV incidence. PrEP-specific HCV testing guidelines should be guided by local epidemiology.

HIV pre-exposure prophylaxis and incidence of sexually transmitted infections in Brazil, 2018 to 2022: An ecological study of PrEP administration, syphilis, and socioeconomic indicators

BACKGROUND

Human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) is one of the pillars of a combination prevention strategy for reducing the risk of new infections caused by HIV. The daily use of antiretroviral drugs by individuals who are not infected with HIV is required to prevent infection. Although its efficacy has been well established in the literature, in recent years, the decreased supply of antiretroviral drugs has been associated with an increase in the incidence of sexually transmitted infections (STI) and changes in the social determinants of health. An ecological study was conducted covering a five-year period (2018-2022), starting from the year of initiation of PrEP administration in Brazilian state capitals.

PRINCIPAL FINDINGS

Descriptive analysis was performed, and the spatial distribution of study data was taken into account. Correlation analysis was used to assess the association between PrEP administration, the incidence and detection rate of STI, and socioeconomic data. The southern region showed the highest incidence rates of STI, but the northern and northeastern regions demonstrated the worst socioeconomic indicators, especially those related to illiteracy and basic sanitation. PrEP administration was significantly correlated with illiteracy (ρ = -0.658), per capita income (ρ = 0.622), public garbage collection (ρ = 0.612), syphilis (ρ = 0.628) and viral hepatitis (ρ = 0.419) incidences. Further, all STI were significantly associated with illiteracy and per capita income.

SIGNIFICANCE

Our findings highlight the need to continue exploring PrEP use and rising syphilis rates. In terms of policy, PrEP administration appears to be inversely associated with regions of greater social vulnerability. Further efforts should focus on the social determinants and health needs of this population to improve access to PrEP and reduce social disparities.

STI Testing among Medicaid Enrollees Initiating PrEP for HIV Prevention in Six Southern States

OBJECTIVES

The purpose of this study was to measure sexually transmitted infection (STI) testing among Medicaid enrollees initiating preexposure prophylaxis (PrEP) to prevent human immunodeficiency virus. Secondary data are in the form of Medicaid enrollment and claims data in six states in the US South.

METHODS

Research partnerships in six states in the US South developed a distributed research network to accomplish study aims. Each state identified all first-time PrEP users in fiscal year 2017-2018 (combined N = 990) and measured the presence of STI testing for chlamydia, syphilis, and gonorrhea through 2019. Each state calculated the percentage of individuals with at least one STI test during 3-, 6-, and 12-month follow-up periods.

RESULTS

The proportion of first-time PrEP users that received an STI test varied by state: 37% to 67% of all of the individuals in each state who initiated PrEP received a test within the first 6 months of PrEP treatment and 50% to 77% received a test within the first 12 months.

CONCLUSIONS

Although the Centers for Disease Control and Prevention recommends STI testing at least every 6 months for PrEP users, our analysis of Medicaid data suggests that STI testing occurs less frequently than recommended in populations at elevated risk of syphilis, gonorrhea, and chlamydia.

Comparison of the burden of self-reported bacterial sexually transmitted infections among men having sex with men across 68 countries on four continents

BACKGROUND

Men who have sex with men (MSM) are in general more vulnerable to sexually transmitted infections (STIs) than the heterosexual men population. However, surveillance data on STI diagnoses lack comparability across countries due to differential identification of MSM, diagnostic standards and methods, and screening guidelines for asymptomatic infections.

METHODS

We compared self-reported overall diagnostic rates for syphilis, gonorrhea, and chlamydia infections, and diagnostic rates for infections that were classified to be symptomatic in the previous 12 months from two online surveys. They had a shared methodology, were conducted in 68 countries across four continents between October 2017 and May 2018 and had 202,013 participants.

RESULTS

Using multivariable multilevel regression analysis, we identified age, settlement size, number of sexual partners, condom use for anal intercourse, testing frequency, sampling rectal mucosa for extragenital testing, HIV diagnosis, and pre-exposure prophylaxis use as individual-level explanatory variables. The national proportions of respondents screened and diagnosed who notified some or all of their sexual partners were used as country-level explanatory variables. Combined, these factors helped to explain differences in self-reported diagnosis rates between countries. The following differences were not explained by the above factors: self-reported syphilis diagnoses were higher in Latin America compared with Europe, Canada, Israel, Lebanon, and the Philippines (aORs 2.30 - 3.71 for symptomatic syphilis compared to Central-West Europe); self-reported gonorrhea diagnoses were lower in Eastern Europe and in Latin America compared with all other regions (aORs 0.17-0.55 and 0.34 - 0.62 for symptomatic gonorrhea compared to Central-West Europe); and self-reported chlamydia diagnoses were lower in Central East and Southeast Europe, South and Central America, and the Philippines (aORs 0.25 - 0.39 for symptomatic chlamydia for Latin American subregions compared to Central West Europe).

CONCLUSIONS

Possible reasons for differences in self-reported STI diagnosis prevalence likely include different background prevalence for syphilis and syndromic management without proper diagnosis, and different diagnostic approaches for gonorrhea and chlamydia.

Determining the screening frequency for sexually transmitted infections for people who use HIV pre-exposure prophylaxis: a systematic review and meta-analysis

OBJECTIVES

Although the World Health Organization recommends 'frequent' screening of sexually transmitted infections (STI) for people who use pre-exposure prophylaxis for HIV, there is no evidence for optimal frequency.

METHODS

We searched five databases and used random-effects meta-analysis to calculate pooled estimates of STI test positivity. We narratively synthesized data on secondary outcomes, including adherence to recommended STI screening frequency and changes in STI epidemiology.

RESULTS

Of 7477 studies, we included 38 for the meta-analysis and 11 for secondary outcomes. With 2-3 monthly STI screening, the pooled positivity was 0.20 (95% confidence interval [CI]: 0.15-0.25) for chlamydia, 0.17 (95% CI: 0.12-0.22) for gonorrhea, and 0.07 (95% CI: 0.05-0.08) for syphilis. For chlamydia and gonorrhea, the positivity was approximately 50% and 75% lower, respectively, in studies that screened 4-6 monthly vs 2-3 monthly. There was no significant difference in the positivity for syphilis in studies that screened 4-6 monthly compared to 2-3 monthly. Adherence of clients to recommended screening frequency varied significantly (39-94%) depending on population and country. Modeling studies suggest more frequent STI screening could reduce incidence.

CONCLUSION

Although more frequent STI screening could reduce delayed diagnoses and incidence, there remain significant knowledge gaps regarding the optimal STI screening frequency.

Intervention treatment distributions that depend on the observed treatment process and model double robustness in causal survival analysis

The generalized g-formula can be used to estimate the probability of survival under a sustained treatment strategy. When treatment strategies are deterministic, estimators derived from the so-called efficient influence function (EIF) for the g-formula will be doubly robust to model misspecification. In recent years, several practical applications have motivated estimation of the g-formula under non-deterministic treatment strategies where treatment assignment at each time point depends on the observed treatment process. In this case, EIF-based estimators may or may not be doubly robust. In this paper, we provide sufficient conditions to ensure the existence of doubly robust estimators for intervention treatment distributions that depend on the observed treatment process for point treatment interventions and give a class of intervention treatment distributions dependent on the observed treatment process that guarantee model doubly and multiply robust estimators in longitudinal settings. Motivated by an application to pre-exposure prophylaxis (PrEP) initiation studies, we propose a new treatment intervention dependent on the observed treatment process. We show there exist (1) estimators that are doubly and multiply robust to model misspecification and (2) estimators that when used with machine learning algorithms can attain fast convergence rates for our proposed intervention. Finally, we explore the finite sample performance of our estimators via simulation studies.

Frequency and Combination of Sequential Sexual Acts That May Lead to Sexually Transmitted Infections at Different Anatomic Sites Within the Same Person

Modeling studies suggest that transmission of gonorrhea and chlamydia to multiple anatomic sites within the same person is necessary to reproduce observed high rates of extragenital gonorrhea/chlamydia. Limited empiric behavioral data support this idea. In this cross-sectional study, we enrolled individuals assigned male at birth who reported sex with men (MSM) and denied receptive anal sex (RAS) in the past 2 years. Participants enrolled in-person at the Sexual Health Clinic in Seattle, Washington (December 2019-September 2021) or online (July 2021-September 2021), and completed a sexual history questionnaire that asked about specific sexual acts and sequence of those acts during their last sexual encounter. We enrolled 210 MSM during the 16-month recruiting period. The median number of sex acts reported at last sexual encounter was 4 (interquartile range 3-5). The most commonly reported acts at last sex were: kissing (83%), receiving oral sex (82%), and insertive anal sex (65%). There was substantial variability in the sequence of acts reported; no unique sequence of sex acts was reported by more than 12% of the population. Ninety percent of participants reported sequences of behaviors that could lead to gonorrhea or chlamydia transmission within the same person (respondent or partner); the most common of these combinations was kissing followed by receiving oral sex (64% reporting). Engaging in multiple sex acts within a single sexual encounter is common and may lead to gonorrhea/chlamydia transmission within the same person. This complicates empiric measurements of transmission probabilities needed to estimate population-level transmission.

Very High Incidence of Chlamydia trachomatis, Neisseria gonorrhoeae, and Treponema pallidum among Low-Risk MSM in an Outpatient Clinic in Wroclaw, Poland in 2019-2020

BACKGROUND

The rise in sexually transmitted infections and chemsex has led to syndemy with HIV, partly due to common routes of transmission and clustered transmissions. Despite this, barriers to STI care and PrEP still remain. We sought to determine whether MSM at low risk for HIV infection were also at low risk for other STIs.

METHODS

The study group was tested for HIV, HCV, and Treponema pallidum, as well as had urethral, rectal, and oropharyngeal smears performed for Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) six months apart. The control group was tested once to define the background incidence.

RESULTS

Treponema pallidum, CT, and NG prevalence was very high at both time points and was similar to the control group. CT was especially common in the control group (20.58%) and the study group at the rectal site at the second time point (9.37%). NG dominated the oropharyngeal site (15.87%), with urethral site sparing. NG infection was associated with an increased number of partners, not condom use (OR, 1.082 [95% CI; 1.009-1.171]). Risk behavior did not change between the time points. Treponema pallidum, CT, and NG incidence was exceptionally high (12.5/100PY, 25.39/100PY, 34.92/100PY, respectively; pooled 87.5/100PY) and was comparable to other studies of high-risk MSM.

CONCLUSIONS

Despite a lower risk for HIV acquisition, the study group was at a very high risk for other STIs, and this risk remained high throughout the study. Patients and medical professionals should be aware of syphilis, gonorrhea, and chlamydiosis transmission risks, and screening should be performed accordingly. Prophylactic programs need to be updated to specifically include lower-risk individuals.

Effect of Screening and Treatment for Gonorrhea and Chlamydia on HIV Incidence Among Men Who Have Sex With Men in the United States: A Modeling Analysis

BACKGROUND

Previous models have estimated the total population attributable fraction of Neisseria gonorrhoeae and Chlamydia trachomatis (NG/CT) on HIV incidence among men who have sex with men (MSM), but this does not represent realistic intervention effects. We estimated the potential impact of screening for NG/CT on downstream incidence of HIV among MSM.

METHODS

Using a network model, we estimated the effects of varying coverage levels for sexually transmitted infection screening among different priority populations: all sexually active MSM regardless of HIV serostatus, MSM with multiple recent (past 6 months) sex partners regardless of serostatus, MSM without HIV, and MSM with HIV. Under the assumption that all screening events included a urethral test, we also examined the effect of increasing the proportion of screening events that include rectal screening for NG/CT on HIV incidence.

RESULTS

Increasing annual NG/CT screening among sexually active MSM by 60% averted 4.9% of HIV infections over a 10-year period (interquartile range, 2.8%-6.8%). More HIV infections were averted when screening was focused on MSM with multiple recent sex partners: 60% coverage among MSM with multiple recent sex partners averted 9.8% of HIV infections (interquartile range, 8.1%-11.6%). Increased sexually transmitted infection screening among MSM without HIV averted more new HIV infections compared with the transmissions averted because of screening MSM with HIV, but fewer NG/CT tests were needed among MSM with HIV to avert a single new HIV infection.

CONCLUSIONS

Screening of NG/CT among MSM is expected to lead to modest but clinically relevant reductions in HIV incidence among MSM.

Sexually Transmitted Infections Among Men and Transgender Women Using HIV Pre-exposure Prophylaxis in a Large Integrated Health System-A Cohort Study

BACKGROUND

Sexually transmitted infections (STIs) are common in people using pre-exposure prophylaxis (PrEP). We examined risk and factors associated with STIs in a cohort of PrEP users in an integrated health system in the United States.

SETTING

The Kaiser Permanente Southern California is a large integrated health system that provides comprehensive medical services to approximately 4.7 million demographically diverse members.

METHODS

We identified men and transgender women initiating PrEP between January 1, 2014, and June 1, 2018, and followed through December 31, 2018. Demographic and clinical factors potentially associated with the risk of bacterial STIs during PrEP use were evaluated using Poisson regression models.

RESULTS

Among 5042 individuals tested for STIs with 7198 person-years of follow-up, 1709 (33.9%) had at least one new STI. The estimated incidence of STIs was 48.3 per 100 person-years, and the most common STI was rectal chlamydia. Most repeat STIs (61.4%) occurred <180 days apart. In a multivariable analysis, an history of STIs in the prior 6 months through 7 days after the PrEP initiation was the most prominent risk factor of STIs during PrEP use (adjusted risk ratio: 1.78, 95% confidence intervals: 1.65 to 1.93). Other risk factors included younger age (<35 years), being Hispanic, and having a history of alcohol use disorder or drug use disorder.

CONCLUSIONS

Quarterly STI testing and targeted intervention to mitigate STI risk are warranted for young and racial minority PrEP users, particularly for those with prior history of STIs and substance use disorders.

Assessing the Impact of HIV Preexposure Prophylaxis Scale-Up on Gonorrhea Incidence Among Gay and Bisexual Men in Sydney: A Mathematical Modeling Study

BACKGROUND

The rollout of preexposure prophylaxis (PrEP) for HIV prevention among gay and bisexual men (GBM) is associated with increases in condomless anal intercourse, potentially increasing the incidence of other sexually transmissible infections (STIs).

METHODS

We developed an individual-based mathematical model to simulate the transmission of Neisseria gonorrhoeae among GBM in Sydney, accounting for changes in sexual practices, STI testing, and PrEP use. We calibrated and validated the model using reported incidence rates for HIV-positive and HIV-negative GBM from 2010 to 2019. Scenarios were run with varying PrEP uptake, PrEP-related STI testing, and PrEP-related sexual behavior and testing intervals up to 2030 to assess the impact of PrEP use on gonorrhea incidence.

RESULTS

Preexposure prophylaxis uptake and associated 3-monthly STI testing from 2015 onward resulted in a predicted increase from 20 to 37 N. gonorrhoeae infections per 100 person-years among HIV-negative GBM by the end of 2020. This is lower than the counterfactual predictions of 45 per 100 person-years if PrEP were not scaled up and 48 per 100 person-years with nonadherence to 3-monthly STI testing. Increasing the time between STI tests for PrEP users by 1 month from 2018 results in the incidence rate among HIV-negative GBM increasing by 8% by 2030. If PrEP coverage doubles from 24% to 53%, incidence among HIV-negative GBM declines by ~25% by 2030.

CONCLUSIONS

Behavior change due to widespread PrEP use may lead to significant increases in gonorrhea incidence in GBM, but the recommended quarterly STI testing recommended for PrEP users should reduce incidence by 18% by 2030.

Real-world trends in incidence of bacterial sexually transmissible infections among gay and bisexual men using HIV pre-exposure prophylaxis (PrEP) in Australia following nationwide PrEP implementation: an analysis of sentinel surveillance data

BACKGROUND

Although data from large implementation trials suggest that sexually transmissible infection (STI) risk increases among gay and bisexual men who initiate HIV pre-exposure prophylaxis (PrEP), there are few data on the trends in population-level STI incidence in the years following widespread PrEP implementation. We aimed to describe trends in bacterial STI incidence among gay and bisexual men using PrEP across Australia in the context of broad PrEP availability through Australia's subsidised medicines scheme.

METHODS

We analysed linked clinical data from HIV-negative gay and bisexual men aged 16 years or older who had been prescribed PrEP across a sentinel surveillance clinical network, including 37 clinics in Australia, between Jan 1, 2016, and Dec 31, 2019. Patients were included if they had STI testing at least twice during the observation period. Repeat testing methods were used to calculate chlamydia, gonorrhoea, syphilis, and any STI incidence rates during individuals' periods of PrEP use. Incidence rate ratios (IRRs) for estimated change in incidence per half calendar year (6-month) period were calculated using negative binomial regression. Secondary analyses compared STI incidence rates across individuals initiating PrEP in each year from 2016 to 2019, as well as by length of time using PrEP (per each additional 6 months of PrEP use).

FINDINGS

22 730 men were included in the analyses. During the observation period, 11 351 chlamydia infections were diagnosed in 6630 (30·1%) of 22 034 men over 25 991·2 person-years of PrEP use (incidence rate 43·7 cases [95% CI 42·9-44·5] per 100 person-years). Chlamydia incidence decreased from 48·7 cases per 100 person-years in July-December, 2016, to 42·0 cases per 100 person-years in July-December, 2019 (IRR for estimated change per 6-month period 0·98 [95% CI 0·97-0·99]; p=0·0031). 9391 gonorrhoea infections were diagnosed in 5885 (26·9%) of 21 845 men over 24 858·7 person-years of PrEP use (incidence rate 37·8 cases [95% CI 37·0-38·5] per 100 person-years). Gonorrhoea incidence decreased from 45·5 cases per 100 person-years in July-December, 2016, to 37·2 cases per 100 person-years in July-December, 2019 (IRR 0·97 [95% CI 0·96-0·98]; p<0·0001). Declines in chlamydia and gonorrhoea incidence were most prominent in the first 18 months of observation and incidence was stable thereafter. 2062 syphilis infections were diagnosed in 1488 (7·7%) of 19 262 men over 21 978·9 person-years of PrEP use (incidence rate 9·4 cases [95% CI 9·0-9·8] per 100 person-years). Syphilis incidence increased from 6·2 cases per 100 person-years in July-December, 2016, to 9·8 cases per 100 person-years in July-December, 2019 (IRR 1·08 [95% CI 1·05-1·10]; p<0·0001).

INTERPRETATION

Chlamydia and gonorrhoea incidence among gay and bisexual men using PrEP were highest in the early months of PrEP implementation in Australia and stabilised at slightly lower rates thereafter following wider PrEP uptake. Lower prospective STI risk among people initiating PrEP in later years contributed to the observed trends in STI incidence. Widespread PrEP implementation can contribute to increased STI screening and detection.

FUNDING

Australian Department of Health, National Health and Medical Research Council.

Sexually Transmitted Infection Testing, Prevalence, and Treatment among Individuals Receiving HIV Pre-Exposure Prophylaxis within an Integrated Healthcare Delivery System

BACKGROUND

Initial and follow-up sexually transmitted infection (STI) and HIV testing is recommended when taking HIV preexposure prophylaxis (PrEP). We assessed STI services before and after PrEP initiation among persons aged ≥18 years.

METHODS

We conducted this retrospective cohort study at an US integrated healthcare delivery system. We measured HIV/STI testing rates, STI prevalence and treatment at 3 time points: (1) at PrEP initiation, (2) at 120 days, and (3) at 210 days.

RESULTS

Of 685 PrEP initiators, 67.2% continued PrEP use at 120 days and 49.5% at 210 days. Of PrEP users, HIV and STI testing were > 85% and > 80%, respectively, at all 3 time points. Prevalence for any chlamydia, rectal chlamydia, and any gonorrhea, rectal gonorrhea, or pharyngeal gonorrhea was always high at the 120 days and 210 days (e.g, 6.9%, 10.5%, 6.7%, 5.0%, and 5.2%, respectively, at the 120-days for continuous PrEP users). Over 90% of all individuals who tested positive for chlamydia and/or gonorrhea received antibiotic pharmacy fills within seven days at 120 days and 210 days. Monthly PrEP-related pharmacy cost was about $2259-$2659. The proportion of the total medical cost that was PrEP-related pharmacy was about 82% for PrEP continuous users.

CONCLUSIONS

Although HIV/STI testing rates were high, they can still be improved during HIV PrEP management. High STI prevalence after PrEP initiation in this study suggests that patients taking PrEP are at risk of acquiring an STI. Interventions to improve STI services during PrEP management are continuously needed.

Trends in Sexual Behavior and Sexually Transmitted Infections After Initiating Human Immunodeficiency Virus Pre-Exposure Prophylaxis in Men Who Have Sex with Men from Amsterdam, the Netherlands: A Longitudinal Exposure-Matched Study

Men who have sex with men (MSM) initiating human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) may increase condomless anal sex (CAS) and number of partners, and, consequently, more often acquire sexually transmitted infections (STIs). Using data from the Amsterdam Cohort Studies, we compared sexual behavior and STI among MSM after PrEP-initiation with controls not initiating PrEP. The MSM reported on sexual behavior and were tested for HIV, chlamydia, gonorrhea, and syphilis semi-annually. We matched MSM who initiated PrEP between January 1, 2015 and December 31, 2019 1:1 to MSM who did not use time-dependent propensity scores based on age, sexual behavior, and STI. Primary end-points were number of casual partners, and proportion with CAS and receptive CAS (rCAS) with casual partners, sexualized drug use (SDU), any STI, and anal STI. We modeled end-points during the 4 years before and 2 years after PrEP-initiation or matched PrEP-initiation timepoint by using logistic regression (dichotomous end-points) or negative binomial regression (count end-point), adjusted for calendar year. Two hundred twenty-eight out of the 858 (26.6%) MSM initiated PrEP. We matched 198 out of 228 (86.8%) to a control. Before PrEP-initiation, end-points increased over time in both groups, with no statistically significant difference. The odds of CAS, rCAS, and anal STI were on average higher after than before PrEP-initiation in PrEP initiators, whereas after versus before differences were not observed in controls. After PrEP-initiation, PrEP initiators had statistically significantly more casual partners, and higher odds of CAS, rCAS, SDU, any STI, and anal STI than controls. These findings support frequent STI screening and counseling in MSM using PrEP.

Can we screen less frequently for STI among PrEP users? Assessing the effect of biannual STI screening on timing of diagnosis and transmission risk in the AMPrEP Study

BACKGROUND

In many countries, HIV pre-exposure prophylaxis (PrEP) users are screened quarterly for STIs. We assessed the consequences of less frequent STI testing. We also assessed determinants of asymptomatic STI and potential for onward transmission.

METHODS

Using data from the AMPrEP study, we assessed the proportion of syphilis, and genital, anal, and pharyngeal chlamydia and gonorrhoea diagnoses which would have been delayed with biannual versus quarterly screening. We assessed the potential for onward transmission by examining reported condomless anal sex (CAS) in periods after to-be-omitted visits when screening biannually. We assessed determinants of incident asymptomatic STIs using Poisson regression and calculated individual risk scores on the basis of the coefficients from this model.

RESULTS

We included 366 participants. Median follow-up was 47 months (IQR 43-50). 1,183STIs were diagnosed, of which 932(79%) asymptomatic. With biannual screening, 483 asymptomatic STIs (52%) diagnoses would have been delayed at 364 study visits. Of these visits, 129 (35%), 240 (66%) and 265 (73%) were followed by periods of CAS with steady, known casual or unknown casual partners, respectively. Older participants had a lower risk of asymptomatic STI (incidence rate ratio (IRR) 0.86/10-year increase, 95% CI 0.80 to 0.92), while CAS with known (IRR 1.36, 95% CI 1.10 to 1.68) and unknown (IRR 1.86, 95% CI 1.48 to 2.34) casual partners and chemsex (IRR 1.51, 95% CI 1.28 to 1.78) increased the risk. The individual risk scores had limited predictive value (sensitivity=0.70 (95% CI 0.66 to 0.74), specificity=0.50 (95% CI 0.48 to 0.51)).

CONCLUSION

Reducing the STI screening frequency to biannually among PrEP users will likely result in delayed diagnoses, potentially driving onward transmission. Although determinants for asymptomatic STIs were identified, predictive power was low.