Prevalence and correlates of and a risk score to identify asymptomatic anorectal gonorrhoea and chlamydia infection among men who have sex with men in Kisumu, Kenya

Challenges and Solutions to STI Control in the Era of HIV and STI Prophylaxis

PURPOSE OF REVIEW

This article reviews current efforts to control bacterial sexually transmitted infections (STIs) among HIV pre-exposure prophylaxis (PrEP) users and outlines the opportunities and challenges to controlling STIs within HIV PrEP programs.

RECENT FINDINGS

The incidence of STIs continues to rise globally especially among HIV PrEP users, with an estimated 1 in 4 PrEP users having a curable bacterial STI. STIs and HIV comprise a syndemic needing dual interventions. The majority of STIs are asymptomatic, and when testing is available, many STIs occur in extragenital sites that are missed when relying on urine testing or genital swabs. Optimal testing and treatment, including testing for antimicrobial resistance, pose difficulties in high income countries and is essentially non-existent in most low- and middle-income countries. Novel STI primary prevention strategies, like doxycycline post-exposure prophylaxis (PEP) for STI prevention, have proven to be highly efficacious in some populations. A few jurisdictions have issued normative guidelines and position statements for doxycycline PEP; however, clinical standards for implementation and data on public health impact are limited. STI incidence rates are high and rising in sexually active populations. Sexual health programs should leverage the expansion of HIV PrEP delivery services to integrate STI testing, surveillance, and novel STI prevention services.

Derivation and Internal Validation of a Risk Score for Predicting Chlamydia trachomatis Infection in Kenyan Women Planning Conception

BACKGROUND

Availability of laboratory confirmation of sexually transmitted infections is increasing in low- and middle-income countries, but costs continue to limit their access. Chlamydia trachomatis (CT) is a sexually transmitted infection of significant clinical importance, particularly among women. This study aimed to develop a risk score to identify women with a higher likelihood of CT infection, who could then be prioritized for laboratory testing, in a population of Kenyan women planning pregnancies.

METHODS

Women with fertility intentions were included in this cross-sectional analysis. Logistic regression was used to estimate odds ratios for the association between demographic, medical, reproductive, and behavioral characteristics and the prevalence of CT infection. A risk score was developed and validated internally based on the regression coefficients in the final multivariable model.

RESULTS

The prevalence of CT was 7.4% (51 of 691). A risk score for predicting CT infection, with scores 0 to 6, was derived from participants' age, alcohol use, and presence of bacterial vaginosis. The prediction model yielded an area under the receiver operating curve of 0.78 (95% confidene interval [Cl], 0.72-0.84). A cutoff of ≤2 versus >2 identified 31.8% of women as higher risk with moderate sensitivity (70.6%; 95% Cl, 56.2-71.3) and specificity (71.3%; 95% Cl, 67.7-74.5). The bootstrap-corrected area under the receiver operating curve was 0.77 (95% Cl, 0.72-0.83).

CONCLUSIONS

In similar populations of women planning pregnancies, this type of risk score could be useful for prioritizing women for laboratory testing and would capture most women with CT infections while performing more costly testing in less than half of the population.

Inadequate performance of a risk score to predict asymptomatic Neisseria gonorrhoeae and Chlamydia trachomatis infection among cisgender men who have sex with men

OBJECTIVES

Epidemiological treatment of persons who are sexual contacts to partners with Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT) often results in treatment of uninfected persons, which may increase the risk of antibiotic-resistant infections. We sought to identify the predictors of NG and/or CT infections to develop a risk score that could be used to limit epidemiological treatment to persons most likely to have these infections.

METHODS

We included visits to the Public Health - Seattle & King County Sexual Health Clinic by asymptomatic cisgender men who have sex with men (MSM) aged ≥18 who presented as a sexual contact to partner(s) with CT or NG infection between 2011 and 2019. We used logistic regression to estimate the odds of CT and/or NG infections associated with demographic and clinical predictors, selecting the final set of predictors using the Akaike information criteria and obtaining score weights from model coefficients. We used a cross-validation approach to obtain average model discrimination from each of 10 models, leaving out 10% of the data, and evaluated sensitivity and specificity at various score cut-offs.

RESULTS

The final model for predicting NG or CT infection included seven predictors (age <35 years, HIV status, receptive oral sex in the prior 2 months, CT diagnosis, condomless receptive anal intercourse, condomless insertive anal intercourse and methamphetamine use in the prior 12 months). Model discrimination, as measured by the receiver operating curve, was 0.60 (95% CI 0.54 to 0.66). Sensitivity for detection of infection was ≥90% for scores ≥3, ≥5 and ≥7; specificity for these cut-offs was <16%. At scores ≥9, ≥12 and ≥14, specificity increased but sensitivity decreased to ≤76%.

CONCLUSIONS

Our risk score did not sufficiently discriminate between asymptomatic MSM with and without NG/CT infection. Additional studies evaluating epidemiological treatment as a standard of care in diverse populations are needed to guide best practices in the management of contacts to NG/CT infection.

Prevalence of gonococcal and chlamydial infections among men who have sex with men in sub-Saharan Africa: protocol for a systematic review and meta-analysis

BACKGROUND

Bacterial sexually transmitted infections (STIs) including Neisseria gonorrhoeae and Chlamydia trachomatis are common in men who have sex with men (MSM). These infections increase the risk of acquiring and transmitting human immunodeficiency virus (HIV) in this key population. Access to MSM in many countries in sub-Saharan Africa remains generally difficult due to discrimination or criminalization of their sexual orientation which could lead to depression and risky sexual practices associated with prevalence. This protocol therefore proposes to undertake a systematic review and meta-analysis of literature on the prevalence of gonococcal and chlamydial infections among MSM in Sub-Saharan Africa.

METHODS

This review which aims to ascertain the pooled prevalence and risk factors of these infections in sub-Saharan Africa's MSM population will follow the Preferred Reporting Items for Systematic Review and Meta-analyses (PRISMA) guidelines. The search strategy will review relevant articles from the following databases: PubMed, Scopus, ISI Web of Science and the Directory of Open Access Journals (DOAJ). Articles screening for eligibility and data extraction will be conducted by two independent reviewers. All discrepancies will be resolved by the third and fourth reviewers. Heterogeneity in studies will be evaluated using the I2 statistic and where heterogeneity is high and significant, a random effect model will be used to estimate the pooled prevalence. Publication bias will be assessed using the Doi plot. Extracted data will be analysed using MetaXL add-on for Microsoft excel. Data will be presented in tables and graphically presented in forest plots.

DISCUSSION

In this study, we anticipate being able to systematically determine the prevalence of Neisseria gonorrhoeae and Chlamydia trachomatis among MSM as well as explore possible risk factors associated with prevalence. The outcomes of the systematic review and meta-analyses will serve to support researchers and public health stakeholders in identifying healthcare priorities and in addressing issues pertaining to the overall wellbeing of the MSM community.

SYSTEMATIC REVIEW REGISTRATION

PROSPERO CRD42022327095.

Risk Prediction Score for Screening Asymptomatic Sexually Transmitted Infections in HIV-positive French Men Who Have Sex with Men (ANRS 9520 DRIVER)

OBJECTIVES

Asymptomatic sexually transmitted infections (STI) are frequent among men who have sex with men (MSM). Identifying asymptomatic STIs is a crucial issue, not only for secondary but also for primary prevention, as early treatment can reduce transmission risk. We aimed to develop a self-reported predictive score for early identification of asymptomatic STIs.

METHODS

Participants provided clinical data and completed a self-administered questionnaire including sociodemographic variables and behaviors during the 6 previous months. We used multivariable logistic regression to identify factors associated with asymptomatic STIs. We calculated the accuracy of the model by the non-parametric area (AUC) under the receiver-operating-characteristic (ROC) curve to find the optimal discriminant threshold for screening.

RESULTS

A total of 781 HIV-positive MSM were included with a mean age of 46.8 years. Asymptomatic STI prevalence was 13.2%. Detectable plasma HIV RNA (adjusted odds ratio (aOR [95% CI): 2.54 [1.23;5.25]), inconsistent condom use during anal sex (2.20 [1.36;3.56]), group sex (2.00 [1.15;3.45]), during or-genital practices (1.83 [1.12;3.01]), not being in stable relationship (1.70 [1.01;2.66] and an item from a sensation-seeking behavioral scale "I don't like watching porn videos" (1.61 [1.01;2.59] were associated with asymptomatic STI. AUC was 0.7 and with optimal threshold of 0.1082 for this model; sensitivity was 80.4%. Self-reported asymptomatic STI predictive score was built with this threshold according to the 6 factors in the final model.

CONCLUSIONS

As this predictive score is not designed to be diagnostic, but to provide indications for diagnostic tests, its ease of administration and sensitivity remain the most important features. Its use in clinical practice for early detection of asymptomatic STIs potentially can reinforce STI primary and secondary prevention.

Identifying youth at high risk for sexually transmitted infections in community-based settings using a risk prediction tool: a validation study

BACKGROUND : Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) are the most common bacterial sexually transmitted infections (STIs) worldwide. In the absence of affordable point-of-care STI tests, WHO recommends STI testing based on risk factors. This study aimed to develop a prediction tool with a sensitivity of > 90% and efficiency (defined as the percentage of individuals that are eligible for diagnostic testing) of < 60%.

METHODS

This study offered CT/NG testing as part of a cluster-randomised trial of community-based delivery of sexual and reproductive health services to youth aged 16-24 years in Zimbabwe. All individuals accepting STI testing completed an STI risk factor questionnaire. The outcome was positivity for either CT or NG. Backwards-stepwise logistic regression was performed with p ≥ 0.05 as criteria for exclusion. Coefficients of variables included in the final multivariable model were multiplied by 10 to generate weights for a STI risk prediction tool. A maximum likelihood Receiver Operating Characteristics (ROC) model was fitted, with the continuous variable score divided into 15 categories of equal size. Sensitivity, efficiency and number needed to screen were calculated for different cut-points.

RESULTS

From 3 December 2019 to 5 February 2020, 1007 individuals opted for STI testing, of whom 1003 (99.6%) completed the questionnaire. CT/NG prevalence was 17.5% (95% CI 15.1, 19.8) (n = 175). CT/NG positivity was independently associated with being female, number of lifetime sexual partners, relationship status, HIV status, self-assessed STI risk and past or current pregnancy. The STI risk prediction score including those variables ranged from 2 to 46 with an area under the ROC curve of 0.72 (95% CI 0.68, 0.76). Two cut-points were chosen: (i) 23 for optimised sensitivity (75.9%) and specificity (59.3%) and (ii) 19 to maximise sensitivity (82.4%) while keeping efficiency at < 60% (59.4%).

CONCLUSIONS

The high prevalence of STIs among youth, even in those with no or one reported risk factor, may preclude the use of risk prediction tools for selective STI testing. At a cut-point of 19 one in six young people with STIs would be missed.

Rectal gonorrhoea and chlamydia among men who have sex with men in coastal Kenya

Background: Men who have sex with men (MSM) have a higher prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections compared to the rest of the population, often remaining undiagnosed. In Kenya, prevalence of rectal CT and NG infection and NG antimicrobial sensitivity are poorly described. Methods: MSM who reported receptive anal intercourse (RAI) were recruited from an ongoing human immunodeficiency virus acquisition and treatment study in coastal Kenya in 2016-2017. Rectal swabs were collected at two time points 6 months apart to estimate prevalence and incidence of CT/NG infection using a molecular point-of-care assay. Participants positive for CT or NG were treated according to national guidelines. NG culture and antimicrobial susceptibility testing was performed. Participant and risk behaviour characteristics were collected and association with baseline CT/NG prevalence assessed by multivariable regression analysis. Results: Prevalence of CT/NG in 104 MSM was 21.2% (CT 13.5%, NG 9.6%, dual infection 1.9%) at baseline and 25.9% in 81 MSM at follow-up (CT 14.8%, NG 14.8%, dual infection 3.7%). CT/NG incidence was estimated at 53.0 (95% CI, 34.5-81.3) per 100 person-years. Most CT/NG positive participants were asymptomatic: 95.5% at baseline and 100% at follow-up. CT/NG infection was associated with being paid for sex [adjusted odds ratio (aOR)=6.2, 95% CI (1.7-22.9)] and being in formal employment [aOR=7.5, 95% CI (1.1-49.2)]. Six NG isolates were obtained at follow-up; all were susceptible to ceftriaxone and cefixime and all were resistant to penicillin, tetracycline and ciprofloxacin. Conclusions: There is a high prevalence and incidence of asymptomatic rectal CT and NG in MSM reporting RAI in coastal Kenya. MSM who were paid for sex or had formal employment were more likely to be infected with CT/NG suggesting increased risk behaviour during transactional sex. Antimicrobial susceptibility results suggest that current antibiotic choices in Kenya are appropriate for NG treatment.

Rectal gonorrhoea and chlamydia among men who have sex with men in coastal Kenya

Background: Men who have sex with men (MSM) have a higher prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections compared to the rest of the population, often remaining undiagnosed. In Kenya, prevalence of rectal CT and NG infection and NG antimicrobial sensitivity are poorly described. Methods: MSM who reported receptive anal intercourse (RAI) were recruited from an ongoing human immunodeficiency virus acquisition and treatment study in coastal Kenya in 2016-2017. Rectal swabs were collected at two time points 6 months apart to estimate prevalence and incidence of CT/NG infection using a molecular point-of-care assay. Participants positive for CT or NG were treated according to national guidelines. NG culture and antimicrobial susceptibility testing was performed. Participant and risk behaviour characteristics were collected and association with baseline CT/NG prevalence assessed by multivariable regression analysis. Results: Prevalence of CT/NG in 104 MSM was 21.2% (CT 13.5%, NG 9.6%, dual infection 1.9%) at baseline and 25.9% in 81 MSM at follow-up (CT 14.8%, NG 14.8%, dual infection 3.7%). CT/NG incidence was estimated at 53.0 (95% CI, 34.5-81.3) per 100 person-years. Most CT/NG positive participants were asymptomatic: 95.5% at baseline and 100% at follow-up. CT/NG infection was associated with being paid for sex [adjusted odds ratio (aOR)=6.2, 95% CI (1.7-22.9)] and being in formal employment [aOR=7.5, 95% CI (1.1-49.2)]. Six NG isolates were obtained at follow-up; all were susceptible to ceftriaxone and cefixime and all were resistant to penicillin, tetracycline and ciprofloxacin. Conclusions: There is a high prevalence and incidence of asymptomatic rectal CT and NG in MSM reporting RAI in coastal Kenya. MSM who were paid for sex or had formal employment were more likely to be infected with CT/NG suggesting increased risk behaviour during transactional sex. Antimicrobial susceptibility results suggest that current antibiotic choices in Kenya are appropriate for NG treatment.

Rectal gonorrhoea and chlamydia among men who have sex with men in coastal Kenya

Background: Men who have sex with men (MSM) have a higher prevalence of Chlamydia trachomatis (CT) and Neisseria gonorrhoeae (NG) infections compared to the rest of the population, often remaining undiagnosed. In Kenya, prevalence of rectal CT and NG infection and NG antimicrobial sensitivity are poorly described. Methods: MSM who reported receptive anal intercourse (RAI) were recruited from an ongoing human immunodeficiency virus acquisition and treatment study in coastal Kenya in 2016-2017. Rectal swabs were collected at two time points 6 months apart to estimate prevalence and incidence of CT/NG infection using a molecular point-of-care assay. Participants positive for CT or NG were treated according to national guidelines. NG culture and antimicrobial susceptibility testing was performed. Participant and risk behaviour characteristics were collected and association with baseline CT/NG prevalence assessed by multivariable regression analysis. Results: Prevalence of CT/NG in 104 MSM was 21.2% (CT 13.5%, NG 9.6%, dual infection 1.9%) at baseline and 25.9% in 81 MSM at follow-up (CT 14.8%, NG 14.8%, dual infection 3.7%). CT/NG incidence was estimated at 53.0 (95% CI, 34.5-81.3) per 100 person-years. Most CT/NG positive participants were asymptomatic: 95.5% at baseline and 100% at follow-up. CT/NG infection was associated with being paid for sex [adjusted odds ratio (aOR)=6.2, 95% CI (1.7-22.9)] and being in formal employment [aOR=7.5, 95% CI (1.1-49.2)]. Six NG isolates were obtained at follow-up; all were susceptible to ceftriaxone and cefixime and all were resistant to penicillin, tetracycline and ciprofloxacin. Conclusions: There is a high prevalence and incidence of asymptomatic rectal CT and NG in MSM reporting RAI in coastal Kenya. MSM who were paid for sex or had formal employment were more likely to be infected with CT/NG suggesting increased risk behaviour during transactional sex. Antimicrobial susceptibility results suggest that current antibiotic choices in Kenya are appropriate for NG treatment.

Rectal gonorrhoea and chlamydia among men who have sex with men in coastal Kenya

Background: Men who have sex with men (MSM) experience a high burden of Chlamydia trachomatis (CT) and Neisseria gonorrhoea (NG) infections. These remain largely undiagnosed in the context of syndromic treatment. In Kenya, prevalence of rectal CT and NG infection and NG antimicrobial sensitivity are poorly described. Methods: MSM who reported receptive anal intercourse (RAI) were recruited from an ongoing human immunodeficiency virus acquisition and treatment study in coastal Kenya in 2016-2017. Rectal swabs were collected at two time points 6 months apart to estimate prevalence of CT/NG using a molecular point-of-care assay. Participants positive for CT or NG were treated according to national guidelines. NG culture and antimicrobial susceptibility testing was performed. Participant and risk behaviour characteristics were collected and association with baseline CT/NG prevalence was assessed by multivariable regression analysis. Results: Prevalence of CT/NG in 104 MSM was 21.2% (CT 13.5%, NG 9.6%, dual infection 1.9%) at baseline and 25% in 84 MSM at follow-up (CT 14.3%, NG 14.3%, dual infection 3.6%). Most CT/NG positive participants were asymptomatic: 95.5% at baseline and 100% at follow-up. CT/NG infection was associated with being paid for sex (aOR=6.2, 95%CI (1.7-22.9)) and being in formal employment (aOR=7.5, 95%CI (1.14-49.2)). Six NG isolates were obtained at follow-up; all isolates were susceptible to ceftriaxone and cefixime (1 st line treatment for NG) and all were resistant to penicillin, tetracycline and ciprofloxacin. Conclusions: The high prevalence of asymptomatic rectal CT and NG in MSM reporting RAI demonstrates the need for frequent screening or presumptive treatment. MSM who were paid for sex or had formal employment were more likely to be infected with CT/NG, suggesting increased risk behaviour during transactional sex. Antimicrobial susceptibility results suggest that current antibiotic choices in Kenya are appropriate for NG treatment.