Risk of HIV Acquisition Among Men Who Have Sex With Men Infected With Bacterial Sexually Transmitted Infections: A Systematic Review and Meta-Analysis

Bacterial sexually transmitted infections among men who have sex with men and transgender women using oral pre-exposure prophylaxis in Latin America (ImPrEP): a secondary analysis of a prospective, open-label, multicentre study

BACKGROUND

The global burden of sexually transmitted infections (STIs) poses a challenge in the context of HIV pre-exposure prophylaxis (PrEP) programmes. We aimed to explore factors associated with prevalent, incident, and recurrent STIs in men who have sex with men (MSM) and transgender women on PrEP in Brazil, Mexico, and Peru.

METHODS

ImPrEP was a prospective, single-arm, open-label, multicentre study that enrolled MSM and transgender women in the context of the public health systems of Brazil (14 sites), Mexico (four sites), and Peru (ten sites) between February, 2018, and June, 2021. Eligibility criteria followed regional PrEP guidelines at the study start, including participants aged 18 years and older, not living with HIV, and reporting at least one of the following in the previous 6 months: condomless anal sex (CAS), anal sex with partner(s) living with HIV, any bacterial STI, or transactional sex. Eligible participants were screened and enrolled on the same day to receive daily oral PrEP (tenofovir disoproxil fumarate 300 mg and emtricitabine 200 mg). We assessed three outcomes: prevalent bacterial STIs, incident bacterial STIs, and recurrent bacterial STIs. Testing occurred at baseline and quarterly for syphilis, anorectal chlamydia, and anorectal gonorrhoea. Behavioural data were collected at baseline and quarterly. The study was registered with the Brazilian Registry of Clinical Trials, U1111-1217-6021.

FINDINGS

Among all 9509 participants included in the ImPrEP study (3928 [41·3%] in Brazil, 3288 [34·6%] in Mexico, and 2293 [24·1%] in Peru), 8525 (89·7%) had available STI results at baseline and were included in the prevalent STI analysis, and 7558 (79·5%) had available STI results during follow-up and were included in the incident and recurrent STI analyses. 2184 (25·6%) of 8525 participants had any bacterial STI at baseline. STI incidence during follow-up was 31·7 cases per 100 person-years (95% CI 30·7-32·7), with the highest rate for anorectal chlamydia (11·6 cases per 100 person-years, 95% CI 11·0-12·2), followed by syphilis (10·5 cases per 100 person-years, 9·9-11·1) and anorectal gonorrhoea (9·7 cases per 100 person-years, 9·2-10·3). Although only 2391 (31·6%) of 7558 participants had at least one STI during follow-up, 915 (12·1%) participants had recurrent diagnoses, representing 2328 (61·2%) of 3804 incident STI diagnoses. Characteristics associated with prevalent, incident, and recurrent STIs included younger age, multiple sex partners, receptive CAS, substance use, and previous STI diagnoses at baseline (incident or recurrent only).

INTERPRETATION

Our findings underscore the nuanced dynamics of STI transmission among MSM and transgender women across Latin America, highlighting an urgent need for tailored interventions to mitigate STI burden effectively, especially among the most susceptible individuals.

FUNDING

Unitaid, WHO, and ministries of health (Brazil, Mexico, and Peru).

TRANSLATIONS

For the Portuguese and Spanish translations of the abstract see Supplementary Materials section.

Impact of varying pre-exposure prophylaxis programs on HIV and Neisseria gonorrhoeae transmission among MSM in the Netherlands: a modelling study

BACKGROUND

In 2019, a five-year pre-exposure prophylaxis (PrEP) program started in the Netherlands, in which up to 8,500 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 prospective PrEP programs from 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) for t.

RESULTS

At a capacity of 8,500 participants and 3-monthly consultations, the PrEP program could lead to 3,140 (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 numbers 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 numbers of consultations: 589,330 (95%CrI 586,240 - 591,160) and 272,590 (95%CrI 271,770 - 273,290) respectively.

CONCLUSION

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 consultations frequency could be reduced without reducing the number of averted infections if capacity is increased.

Preventing Behavioral Human Immunodeficiency Virus Infections in Adolescents and Young Adults

HIV prevention in adolescents and young adults (AYA) requires a multi-pronged strategy encompassing behavioral, biologic, and structural approaches. This article reviews the epidemiology of HIV infection in the United States and its pathogenesis and transmission. Prevention approaches are discussed in more detail, with an emphasis on how each approach is relevant to AYA populations. Information is summarized in a resource table with links to references and in-depth discussions of the topics reviewed in this article.

Antimicrobial treatment and resistance in sexually transmitted bacterial infections

Sexually transmitted infections (STIs) have been part of human life since ancient times, and their symptoms affect quality of life, and sequelae are common. Socioeconomic and behavioural trends affect the prevalence of STIs, but the discovery of antimicrobials gave hope for treatment, control of the spread of infection and lower rates of sequelae. This has to some extent been achieved, but increasing antimicrobial resistance and increasing transmission in high-risk sexual networks threaten this progress. For Neisseria gonorrhoeae, the only remaining first-line treatment (with ceftriaxone) is at risk of becoming ineffective, and for Mycoplasma genitalium, for which fewer alternative antimicrobial classes are available, incurable infections have already been reported. For Chlamydia trachomatis, in vitro resistance to first-line tetracyclines and macrolides has never been confirmed despite decades of treatment of this highly prevalent STI. Similarly, Treponema pallidum, the cause of syphilis, has remained susceptible to first-line penicillin.

Effectiveness of the Therapeutic Lifestyle Change Diet Intervention to Improve Biochemical Markers of Cardiovascular Diseases in HIV-Infected Patients with Dyslipidemia

INTRODUCTION

This randomized controlled trial study aimed to investigate the effectiveness of therapeutic lifestyle change (TLC) diet intervention by the registered dietitians.

METHODS

Eighty-two people living with HIV (PLHIV) with dyslipidemia were randomly allocated to the intervention group as well as another 82 PLHIV with dyslipidemia to the control group. Participants in the intervention group were instructed to meet the registered dietitians every 2 weeks at weeks 0, 2, 4, 6, and 12 (a totally of 12 weeks) to receive individual medical nutrition therapy according to the TLC diet principles, while the participants in the control group only received routine health care service.

RESULTS

Triglycerides, total cholesterol, and LDL cholesterol of the intervention group were significantly lower than those of the control group at the endpoint (p < 0.05). In addition, these biomarkers and C-reactive protein of the intervention group were significantly lower when compared with their baseline (p < 0.05). The overall dietary habits of participants in the intervention group were significantly improved at the end of the study (p < 0.05).

CONCLUSION

The medical nutrition therapy intervention based on the TLC diet is effective in improving blood lipid profiles among PLHIV with dyslipidemia.

Orogenital and anal infection by Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium, and other sexually transmitted infections in men who have sex with men in Lisbon

BACKGROUND

Men who have sex with men (MSM) are at risk for sexually transmitted infections (STIs), but more data on extragenital carriage are needed.

AIM

We assessed the genital and extragenital prevalence of bacterial and other STIs in MSM in a Lisbon sexual health clinic.

METHODS

We screened oral, anal, and urine samples of MSM visiting the GAT-CheckpointLX clinic June 2017-December 2021 for Chlamydia trachomatis (including lymphogranuloma venereum, LGV), Neisseria gonorrhoeae, Mycoplasma genitalium, Trichomonas vaginalis, Mycoplasma hominis, Ureaplasma urealyticum, and U. parvum. Ano-oro-genital lesions were tested for LGV, Treponema pallidum, and Herpes Simplex Virus. Blood was tested for HIV and T. pallidum antibodies.

RESULTS

N. gonorrhoeae was found in 16.6% of the MSM followed by C. trachomatis (13.2%), M. genitalium (10.3%) and T. vaginalis (0.2%). The most frequent occurrence was anorectal (C. trachomatis, M. genitalium) and oral (N. gonorrhoeae). We found high carriage of U. urealyticum (36.1%) and M. hominis (22.1%). LGV was detected in 21.8% of chlamydia-positive anorectal swabs. Syphilis was detected in 22.6% of tested MSM, while 13.8% had HIV. Gonorrhoea and chlamydia were significantly more prevalent in MSM with concomitant HIV or syphilis.

CONCLUSION

The substantial extragenital prevalence of bacterial STIs in MSM, and HIV and syphilis coinfections, suggest screening has value in identifying hidden carriage and in contributing for providing better care.

Changes in Inflammatory Cytokine Levels in Rectal Mucosa Associated With Neisseria gonorrheae and/or Chlamydia trachomatis Infection and Treatment Among Men Who Have Sex With Men in Lima, Peru

BACKGROUND

Neisseria gonorrheae and Chlamydia trachomatis are associated with mucosal inflammation and human immunodeficiency virus 1 (HIV-1) transmission. We assessed levels of inflammatory cytokines in men who have sex with men (MSM) with and without rectal gonorrhea and/or chlamydia in Lima, Peru.

METHODS

We screened 605 MSM reporting condomless receptive anal intercourse for rectal N. gonorrheae/C. trachomatis using nucleic acid testing. We identified 101 cases of gonorrhea and/or chlamydia and randomly selected 50 N. gonorrheae/C. trachomatis positive cases and matched 52 negative controls. We measured levels of IL-1β, IL-6, IL-8, and TNF-α in rectal secretions. Tests for HIV-1, rectal N. gonorrheae/C. trachomatis, and mucosal cytokines were repeated after 3 and 6 months. Cytokine levels in cases and uninfected controls were compared using Wilcoxon rank-sum tests and linear regression.

RESULTS

MSM with gonorrhea/chlamydia had elevated levels of all cytokines in rectal mucosa compared with matched controls (all P values <.001). Following antibiotic treatment there were no significant differences in cytokine levels at 3- or 6-month follow-up evaluations (all P values >.05).

DISCUSSION

Rectal gonorrhea/chlamydia infection is associated with transient mucosal inflammation and cytokine recruitment. Our data provide proof of concept for rectal sexually transmitted infection screening as an HIV prevention strategy for MSM. Clinical Trials Registration. NCT03010020.

An isothermal CRISPR-based diagnostic assay for Neisseria gonorrhoeae and Chlamydia trachomatis detection

IMPORTANCE

A method for Neisseria gonorrhoeae (NG)/Chlamydia trachomatis (CT) detection is developed using multiplex-recombinase polymerase amplification and Cas12a/Cas13a. This method can detect NG and CT simultaneously with high sensitivity and specificity. This method has great potential to be further developed into larger-scale screening and point-of-care testing (POCT).

Sexually Transmitted Infections and the Risk of Reinfection Within 12 Months: A Population-Based Cohort

BACKGROUND

Chlamydia, gonorrhea, and syphilis are common sexually transmitted infections that disproportionately affect specific groups in New Zealand (NZ). Predictors of reinfection are not well studied in NZ but could inform public health strategies to decrease sexually transmitted infection (STI) incidence.

METHODS

New Zealand-wide chlamydia, gonorrhea, and syphilis cases during 2019 were identified using nationally collected data. Cases were followed-up to identify reinfection with the same STI within 12 months of initial infections. Logistic regression models were used to identify predictors for each STI reinfection.

RESULTS

Determinants identified for increased odds of chlamydia reinfection were age groups 16-19 and 20-24 years, females, Māori and Pacific peoples, cases in the Northern region, and cases with at least one test before the initial infection. Age 40 years and older was associated with lower odds of gonorrhea reinfection, as was being of Asian ethnicity, living in Midland or Southern regions, and reporting heterosexual behavior. Region was the only statistically significant predictor for syphilis reinfection, with higher odds of reinfection for people living in the Central region.

CONCLUSIONS

Our findings reflect disproportionate STI rates for some groups in NZ, with younger age groups, Māori and Pacific peoples, men who have sex with men, and people living in the Northern region experiencing higher odds of reinfection. Groups identified with higher odds for reinfection require increased access to culturally responsive health services to treat, understand, and prevent possible reinfection. Changes to current public health strategies could include culturally specific behavioral counseling, and improvements to and adherence to effective contract tracing.

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.

Sexual healthcare and at-home STI test collection: attitudes and preferences of transgender women in the Southeastern United States

Background

HIV and sexually transmitted infections (STIs) disproportionally affect transgender women in the United States, particularly in the Southeast where rates of HIV and bacterial STIs are especially high. Despite the high HIV/STI burden among transgender women, their engagement in sexual healthcare services, including HIV/STI testing, is low. Understanding reasons for this disconnect is essential in developing HIV/STI prevention efforts for this population, especially in the Southeastern US, where access to affirming sexual healthcare providers and resources is limited. We aimed to perform an exploratory qualitative study to describe the attitudes and preferences of transgender women living in Alabama with regards to sexual healthcare and at-home STI test collection.

Methods

Transgender women ≥18 years old residing in Alabama were invited to participate in virtual individual in-depth interviews via Zoom. The interview guide explored participant experiences engaging with sexual healthcare services as well as preferences related to extragenital (i.e., rectal, pharyngeal) and at-home STI testing for gonorrhea and chlamydia. A trained qualitative researcher coded transcripts after each interview and iteratively amended the interview guide as themes emerged. Data were coded and thematically analyzed using NVivo qualitative software.

Results

Between June 2021-April 2022, 22 transgender women were screened and 14 eligible women enrolled. Eight participants were white (57%), and six were black (43%). Five participants (36%) were living with HIV and engaged with HIV care services. Interview themes included preference for sexual healthcare environments specializing in LGBTQ+ care, enthusiasm toward at-home STI testing, an emphasis on affirming patient-provider interactions in sexual healthcare settings, a preference for sexual healthcare providers involved in STI testing who were not cisgender men, and gender dysphoria around sexual health discussions and testing.

Conclusion

Transgender women in the Southeastern US prioritize affirming provider-patient interactions, however resources in the region are limited. Participants were enthusiastic about at-home STI testing options, which have the potential to mitigate gender dysphoria. Further investigation into development of remote sexual healthcare services for transgender women should be performed.

Factors Associated With Chlamydia and Gonorrhea Treatment Completion Among Sexual Health Clinic Patients, Baltimore City, Maryland; 2018 to 2019

BACKGROUND

Prompt and appropriate treatment of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) is critical to prevent transmission and serious sequelae. The objectives were to determine the prevalence of CT/NG treatment completion and identify demographic, behavioral, and clinical factors associated with treatment completion at sexual health clinics in Baltimore City, Maryland.

METHODS

Electronic health record data from patients diagnosed with CT/NG during 2018-2019 were analyzed. Treatment completion was defined as documentation of Centers for Disease Control and Prevention-recommended treatment ≤30 days after testing. Regression was used to assess differences in treatment completion across groups; analyses were stratified by birth sex.

RESULTS

Most of the 2426 male (86%) and 754 (72%) female patients diagnosed with CT/NG completed treatment in ≤30 days; 74% of male and 36% of female patients were treated same-day. Among 890 male patients not treated same-day, treatment completion was associated with other same-day antimicrobial treatments (adjusted prevalence ratio, 0.76 [95% confidence interval, 0.61-0.94]), longer test processing times (≥10 days; 0.78 [0.65-0.95]) infection at multiple anatomic sites (1.49 [1.25-1.76]), and patients with previous clinic visits (1.16 [1.03-1.31]). Among 483 female patients not treated same-day, treatment completion was associated with diagnosis year (2019 vs. 2018; 1.23 [1.05-1.43]) and residential addresses 2 to 5 miles (vs. <2 miles) from clinic (1.25 [1.02-1.53]). Demographic and behavioral characteristics were not associated with treatment completion.

CONCLUSIONS

Substantial proportions of male and female sexual health clinic patients did not complete treatment. Our findings underscore the need for implementation of highly sensitive and specific point-of-care (POC) CT/NG testing to improve treatment completion in this setting.

Postexposure Doxycycline to Prevent Bacterial Sexually Transmitted Infections

BACKGROUND

Interventions to reduce sexually transmitted infections (STIs) among men who have sex with men (MSM) are needed.

METHODS

We conducted an open-label, randomized study involving MSM and transgender women who were taking preexposure prophylaxis (PrEP) against human immunodeficiency virus (HIV) infection (PrEP cohort) or living with HIV infection (persons living with HIV infection [PLWH] cohort) and who had had Neisseria gonorrhoeae (gonorrhea), Chlamydia trachomatis (chlamydia), or syphilis in the past year. Participants were randomly assigned in a 2:1 ratio to take 200 mg of doxycycline within 72 hours after condomless sex (doxycycline postexposure prophylaxis) or receive standard care without doxycycline. STI testing was performed quarterly. The primary end point was the incidence of at least one STI per follow-up quarter.

RESULTS

Of 501 participants (327 in the PrEP cohort and 174 in the PLWH cohort), 67% were White, 7% Black, 11% Asian or Pacific Islander, and 30% Hispanic or Latino. In the PrEP cohort, an STI was diagnosed in 61 of 570 quarterly visits (10.7%) in the doxycycline group and 82 of 257 quarterly visits (31.9%) in the standard-care group, for an absolute difference of -21.2 percentage points and a relative risk of 0.34 (95% confidence interval [CI], 0.24 to 0.46; P<0.001). In the PLWH cohort, an STI was diagnosed in 36 of 305 quarterly visits (11.8%) in the doxycycline group and 39 of 128 quarterly visits (30.5%) in the standard-care group, for an absolute difference of -18.7 percentage points and a relative risk of 0.38 (95% CI, 0.24 to 0.60; P<0.001). The incidences of the three evaluated STIs were lower with doxycycline than with standard care; in the PrEP cohort, the relative risks were 0.45 (95% CI, 0.32 to 0.65) for gonorrhea, 0.12 (95% CI, 0.05 to 0.25) for chlamydia, and 0.13 (95% CI, 0.03 to 0.59) for syphilis, and in the PLWH cohort, the relative risks were 0.43 (95% CI, 0.26 to 0.71), 0.26 (95% CI, 0.12 to 0.57), and 0.23 (95% CI, 0.04 to 1.29), respectively. Five grade 3 adverse events and no serious adverse events were attributed to doxycycline. Of the participants with gonorrhea culture available, tetracycline-resistant gonorrhea occurred in 5 of 13 in the doxycycline groups and 2 of 16 in the standard-care groups.

CONCLUSIONS

The combined incidence of gonorrhea, chlamydia, and syphilis was lower by two thirds with doxycycline postexposure prophylaxis than with standard care, a finding that supports its use among MSM with recent bacterial STIs. (Funded by the National Institutes of Health; DoxyPEP ClinicalTrials.gov number, NCT03980223.).

Sexually transmitted infections and sexual behaviour among men having sex with men from Tshwane, South Africa

BACKGROUND

Men having sex with men (MSM) are at increased risk of acquiring sexually transmitted infections (STIs), including extra-urethral infections. This study aimed to provide information on the presence of genital and extra-genital non-viral STIs and associated risk factors among MSM in the Tshwane district of South Africa.

METHOD

Samples were collected from 200 MSM in the North-western area of Tshwane. After the completion of a questionnaire including demographics and sexual history and an HIV test, three swabs (pharyngeal, rectal, and urethral) were collected and tested for the presence of Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT), Mycoplasma genitalium (MG) and Trichomonas vaginalis (TV).

RESULTS

Data were collected from 199 participants and 77/199 (38.7%) participants had at least one infection regardless of specimen site. Of these 34 (17.1%) were infected with NG; 36 (18.1%) with CT, 16 (8.1%) with MG and 14 (7.0%) with TV. NG and CT were most frequently detected in rectal specimens. The HIV prevalence in this study was 66.8% (133/199), with 56 (28.1%) of participants both STI and HIV positive. Being between 18 and 20 years, and difficulty having safe sex (more sex partners and more often condomless anal sex) when high/drunk were significantly associated with having an STI. Factors with increased odds of having an STI were being HIV positive, having two or more sexual partners, depending on partner financially, performing and receiving rimming, or receiving anal sex.

CONCLUSIONS

This study has highlighted the high burden of STIs in MSM in the local community, especially the prevalence of these pathogens in extra-genital sites.

Update on the Epidemiology, Screening, and Management of Chlamydia trachomatis Infection

Chlamydia trachomatis infection ("chlamydia") is the most commonly diagnosed bacterial sexually transmitted infection globally, occurring in the genitals (urethra or vagina/cervix), rectum, or pharynx. If left untreated in women, genital chlamydia can ascend into the upper genital tract causing pelvic inflammatory disease, increasing their risk for ectopic pregnancy, infertility, and chronic pelvic pain. In men, chlamydia can cause epididymitis and proctitis. However, chlamydia is asymptomatic in over 80% of cases. This article provides an update on the epidemiology, natural history, and clinical manifestations of chlamydia in adults and discusses the current approaches to its management and control policy.

Advances and challenges in sexually transmitted infections prevention among men who have sex with men in Asia

PURPOSE OF REVIEW

This review summarizes recently published research on sexually transmitted infections (STIs) and sexually transmitted diseases (STDs) among men who have sex with men (MSM) in Asia, covering four main areas: prevalence and consequences of STIs/STDs, factors associated with STI risk, strategies and measures of STI prevention, challenges in the prevention of SITs.

RECENT FINDINGS

Studies show that STIs among Asian MSM are still prevalent, with the prevalence of STIs varying slightly from country to country. In addition to the number of sexual partners, frequency of condom use, high-risk sexual behaviors, the influence of Confucianism, law, and COVID-19 are also related to STI risk. Social stigma, weak health systems, lack of funding and policy support are the current challenges for STIs prevention.

SUMMARY

In the future, new media technologies are encouraged to be used to enhance education and reduce stigma and discrimination against MSM and STIs. Expanding STI screening, strengthening STI knowledge propaganda and education among MSM population, and providing necessary counseling and medical services are main strategies in STI prevention. It is also important to strengthen STI awareness and policy support at the national level.

Factors associated with testing for HIV and other sexually transmitted infections in men who have sex with men and transgender women in Bangkok, Thailand

Background

Routine screening for HIV and other sexually transmitted infections (STIs) facilitates early diagnosis and treatment, thereby preventing morbidity and onward transmission. We estimated the prevalence of prior HIV/STI testing among men who have sex with men (MSM) and transgender women (TGW) in Bangkok, Thailand, and identified factors associated with prior testing.

Methods

Cross-sectional analyses were performed using data collected at enrollment into an HIV incidence cohort. From April to October 2017, MSM and TGW were enrolled if they were aged 18–35 years, reported anal intercourse with a male or TGW partner, and reported behavioral vulnerability to HIV. Participants answered questions about demographics, sexual behaviors, and lifetime HIV/STI testing history. Multivariable robust Poisson regression was used to estimate risk ratios (RRs) and 95% confidence intervals (CIs) for factors potentially associated with prior testing.

Results

Among 1,014 participants, 348 (34.3%) were TGW and the median age was 21.6 (interquartile range 20.0-24.8) years. Prior testing for HIV was reported by 421 (41.5%) and for other STIs by 268 (26.4%). HIV testing was more common among participants aged ≥ 22 years (RR 1.37 [95% CI 1.13–1.67]), with college education as compared to secondary or less (RR 1.37 [95% CI 1.08–1.72]), and who met male sexual partners online (RR 1.52 [95% CI 1.24–1.85]), but lower among participants attracted to both men and women as compared to men only (RR 0.64 [95% CI 0.51–0.81]) and who met male sexual partners in bars (RR 0.83 [95% CI 0.72–0.97]). Similar associations were observed with prior testing for other STIs, including increased testing among participants with college education (RR 1.52 [95% CI 1.11–2.09]) and who met male sexual partners online (RR 1.73 [95% CI 1.30–2.31]), but lower among participants attracted to both men and women (RR 0.70 [95% CI 0.51–0.96]) and who met male sexual partners in bars (RR 0.67 [95% CI 0.54–0.83]).

Conclusions

Despite behavioral vulnerability, prior testing for HIV and other STIs was uncommon. Online engagement strategies may be effectively reaching Thai MSM and TGW who meet sexual partners online, but new interventions are needed to encourage testing among younger, less educated, and bisexual MSM and TGW.

Risk of Human Immunodeficiency Virus Acquisition Among High-Risk Heterosexuals With Nonviral Sexually Transmitted Infections: A Systematic Review and Meta-Analysis

BACKGROUND

Nonviral sexually transmitted infections (STIs) increase risk of sexually acquired human immunodeficiency virus (HIV) infection. Updated risk estimates carefully scrutinizing temporality bias of studies are needed.

METHODS

We conducted a systematic review (PROSPERO CRD42018084299) of peer-reviewed studies evaluating variation in risk of HIV infection among high-risk heterosexuals diagnosed with any of: Chlamydia trachomatis, Mycoplasma genitalium, Neisseria gonorrhoeae, Treponema pallidum, and/or Trichomonas vaginalis. We searched PubMed, Web of Science, and Embase databases through December 2017 and included studies where STIs and HIV were assessed using laboratory tests or medical examinations and where STI was diagnosed before HIV. After dual screening, data extraction, and risk of bias assessment, we meta-analytically pooled risk ratios (RRs).

RESULTS

We found 32 eligible studies reporting k = 97 effect size estimates of HIV acquisition risk due to infection with one of the abovementioned STIs. Most data were based on women engaged in sex work or other high-risk occupations in developing countries. Many studies did not measure or adjust for known confounders, including drug injection and condom use, and most were at medium or high risk of bias because of the potential for undetected HIV infection to have occurred before STI infection. Human immunodeficiency virus acquisition risk increased among women infected with any pathogen; the effect was greatest for women infected with Mycoplasma genitalium (RR, 3.10; 95% confidence interval [CI], 1.63-5.92; k = 2) and gonorrhea (RR, 2.81; 95% CI, 2.25-3.50; k = 16) but also statistically significant for women infected with syphilis (RR, 1.67; 95% CI, 1.23-2.27; k = 17), trichomonas (RR, 1.54; 95% CI, 1.31-1.82; k = 17), and chlamydia (RR, 1.49; 95% CI, 1.08-2.04; k = 14). For men, data were space except for syphilis (RR, 1.77; 95% CI, 1.22-2.58; k = 5).

CONCLUSION

Nonviral STI increases risk of heterosexual HIV acquisition, although uncertainty remains because of risk of bias in primary studies.

Contribution of Sex Differences to HIV Immunology, Pathogenesis, and Cure Approaches

Approximately 38 million people were living with human immunodeficiency virus (HIV) in 2020 and 53% of those infected were female. A variety of virological and immunological sex-associated differences (sexual dimorphism) in HIV infection have been recognized in males versus females. Social, behavioral, and societal influences play an important role in how the HIV pandemic has affected men and women differently. However, biological factors including anatomical, physiologic, hormonal, and genetic differences in sex chromosomes can each contribute to the distinct characteristics of HIV infection observed in males versus females. One striking example of this is the tendency for women to have lower HIV plasma viral loads than their male counterparts early in infection, though both progress to AIDS at similar rates. Sex differences in acquisition of HIV, innate and adaptive anti-HIV immune responses, efficacy/suitability of specific antiretroviral drugs, and viral pathogenesis have all been identified. Sex differences also have the potential to affect viral persistence, latency, and cure approaches. In this brief review, we summarize the major biological male/female sex differences in HIV infection and their importance to viral acquisition, pathogenesis, treatment, and cure efforts.

Controversies and evidence on Chlamydia testing and treatment in asymptomatic women and men who have sex with men: a narrative review

Background

Chlamydia trachomatis (CT) is the most common bacterial sexually transmitted infection (STI) worldwide. CT is mainly asymptomatic. Test-and-treat strategies are widely implemented to prevent transmission and complications. Strategies are not without controversy in asymptomatic women and men who have sex with men (MSM). Concerns are emerging to test and treat asymptomatic persons for urogenital CT (‘Controversy 1’) and pharyngeal or rectal CT (‘Controversy 2’), whereby testing symptomatic persons is not under debate. Opposed views in CT treatment involve using azithromycin versus doxycycline (‘Controversy 3’). The objective of this review is to provide coverage of these public health and clinical controversies by reviewing the current scientific evidence.

Methods

A literature search was performed using PubMed for relevant publications between 2018 and September 2021, and iterative retrieval of additional relevant publications.

Results

Controversy 1. In women, the majority of asymptomatic CT are at the urogenital site, and detections mostly include viable CT. CT easily transmits to a partner and potentially also between the vaginal and rectal areas; the clinical impact of urogenital CT is established, although risks for adverse outcomes are uncertain. Wide-scale testing in asymptomatic women has not resulted in reduced prevalence. In MSM, evidence for the clinical impact of asymptomatic urogenital CT is lacking. Controversy 2. Rectal CT is common in women diagnosed with urogenital CT, but the clinical impact of asymptomatic rectal CT is uncertain. In MSM, rectal CT is common, and most CT infections are at the rectal site, yet the risk of longer term complications is unknown. In both sexes, pharyngeal CT is uncommon and has no documented clinical impact. Controversy 3. In the treatment of rectal CT, doxycycline has superior effectiveness to azithromycin. Evidence has also accumulated on the harms of test-and-treat strategies.

Conclusions

Current practices vary widely, from widescale test-and-treat approaches to more individual patient- and partner-level case management. Choosing which asymptomatic people to test at what anatomic site, and whether to test or not, requires an urgent (re-)definition of the goals of testing and treating asymptomatic persons. Treatment guidelines are shifting toward universal doxycycline use, and clinical practice now faces the challenge of implementation.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-022-07171-2.

Test-and-treat is a key strategy in the control of Chlamydia trachomatis (CT). We discuss recent controversies and present scientific evidence regarding urogenital, rectal, and pharyngeal CT test-and-treat strategies in women and in men who have sex with men (MSM). This should inform best practices for the prevention and management of the most common bacterial sexually transmitted infection (STI) worldwide.

Rectal chlamydia infections: implications for reinfection risk, screening, and treatment guidelines

PURPOSE OF REVIEW

Rectal chlamydia is a prevalent sexually transmissible infection in both men who have sex with men (MSM) and in women. Screening is recommended for MSM but remains controversial for women. The optimal treatment for rectal chlamydia is now conclusive but interpreting and managing positive results remains challenging. Infections among MSM are increasing and strategies are needed to reduce incident infections. This review summarizes recent developments for the screening and management of rectal chlamydia and its implications on reinfection.

RECENT FINDINGS

Reinfections in MSM may be occurring due to resumption of sex soon after treatment whereas repeat infections in women may occur due to autoinoculation in the absence of sex. Doxycycline is now first-line treatment but its role in chemoprophylaxis remains unclear. False positive results remain an issue, but the development of viability assays may prove useful in future to determine true infections.

SUMMARY

Doxycycline is the first-line treatment for rectal chlamydia and in women may prevent infections at the urogenital site. Viability assays can help to reduce antibiotic use once developed. The role of routine screening of rectal chlamydia in women remains unclear and this debate may soon include asymptomatic infections in MSM.

Diagnosis and Treatment of Sexually Transmitted Infections: A Review

IMPORTANCE

Approximately 1 in 5 adults in the US had a sexually transmitted infection (STI) in 2018. This review provides an update on the epidemiology, diagnosis, and treatment of gonorrhea, chlamydia, syphilis, Mycoplasma genitalium, trichomoniasis, and genital herpes.

OBSERVATIONS

From 2015 to 2019, the rates of gonorrhea, chlamydia, and syphilis increased in the US; from 1999 to 2016, while the rates of herpes simplex virus type 1 (HSV-1) and HSV-2 declined. Populations with higher rates of STIs include people younger than 25 years, sexual and gender minorities such as men and transgender women who have sex with men, and racial and ethnic minorities such as Black and Latinx people. Approximately 70% of infections with HSV and trichomoniasis and 53% to 100% of extragenital gonorrhea and chlamydia infections are asymptomatic or associated with few symptoms. STIs are associated with HIV acquisition and transmission and are the leading cause of tubal factor infertility in women. Nucleic acid amplification tests have high sensitivities (86.1%-100%) and specificities (97.1%-100%) for the diagnosis of gonorrhea, chlamydia, M genitalium, trichomoniasis, and symptomatic HSV-1 and HSV-2. Serology remains the recommended method to diagnose syphilis, typically using sequential testing to detect treponemal and nontreponemal (antiphospholipid) antibodies. Ceftriaxone, doxycycline, penicillin, moxifloxacin, and the nitroimidazoles, such as metronidazole, are effective treatments for gonorrhea, chlamydia, syphilis, M genitalium, and trichomoniasis, respectively, but antimicrobial resistance limits oral treatment options for gonorrhea and M genitalium. No cure is available for genital herpes. Effective STI prevention interventions include screening, contact tracing of sexual partners, and promoting effective barrier contraception.

CONCLUSIONS AND RELEVANCE

Approximately 1 in 5 adults in the US had an STI in 2018. Rates of gonorrhea, chlamydia, and syphilis in the US have increased, while rates of HSV-1 and HSV-2 have declined. Ceftriaxone, doxycycline, penicillin, moxifloxacin, and the nitroimidazoles are effective treatments for gonorrhea, chlamydia, syphilis, Mycoplasma genitalium, and trichomoniasis, respectively, but antimicrobial resistance limits oral therapies for gonorrhea and Mycoplasma genitalium, and no cure is available for genital herpes.