Sexually transmitted infections (STIs): epidemiological trends and resistance

The global dissemination of ceftriaxone-resistant Neisseria gonorrhoeae FC428-like strains poses a public health concern. To assess and follow their spread, establishing effective antimicrobial resistance (AMR) surveillance systems is essential.

This study aimed to track ceftriaxone-resistant FC428-like strains in parts of China, using a molecular screening tool.

Samples were collected from Sichuan, Zhejiang, Shanghai, and Guangdong provinces between 2019 and 2021. We employed a rapid molecular tool − the high-resolution melting analysis-based FC428 (HRM-FC428) assay, to screen for FC428-like strains. All FC428-like strains detected were further characterised by genotyping and PCR-sequencing.

Of 1,042 tested samples, 44 harboured the penA-60.001 allele linked to ceftriaxone resistance, revealing a 4.2% prevalence of FC428-like strains. The HRM-FC428 assay additionally uncovered six strains with mosaic penA-195.001 or penA-232.001 alleles, both bearing the A311V mutation, a ceftriaxone resistance marker. During the study, the prevalence of FC428-like strains among overall samples appeared to increase, with rates of 2.8% (11/395) in 2019, 4.2% (16/378) in 2020, and 6.3% (17/269) in 2021. Some strains’ sequence types (ST)s were identified across provinces (e.g. ST1903, ST1600) and most strains (24/44) were ST1903, an ST also reported in other regions/countries, suggesting local evolution and global transmission.

Our work underscores the value of culture-independent antimicrobial resistance monitoring and validates the use of molecular diagnostic tools, like the HRM-FC428 assay for this purpose. This study offers insights into the complex landscape of ceftriaxone-resistant N. gonorrhoeae, emphasising the importance of continued surveillance and global collaboration to mitigate this growing public health threat.

Antimicrobial resistance (AMR) of Mycoplasma genitalium (MG) is a growing concern worldwide and surveillance is needed. In Belgium, samples are sent to the National Reference Centre of Sexually Transmitted Infections (NRC-STI) on a voluntary basis and representative or robust national AMR data are lacking.

We aimed to estimate the occurrence of resistant MG in Belgium.

Between July and November 2022, frozen remnants of MG-positive samples from 21 Belgian laboratories were analysed at the NRC-STI. Macrolide and fluoroquinolone resistance-associated mutations (RAMs) were assessed using Sanger sequencing of the 23SrRNA and parC gene. Differences in resistance patterns were correlated with surveillance methodology, socio-demographic and behavioural variables via Fisher’s exact test and logistic regression analysis.

Of the 244 MG-positive samples received, 232 could be sequenced for macrolide and fluoroquinolone RAMs. Over half of the sequenced samples (55.2%) were resistant to macrolides. All sequenced samples from men who have sex with men (MSM) (24/24) were macrolide-resistant. Fluoroquinolone RAMs were found in 25.9% of the samples and occurrence did not differ between socio-demographic and sexual behaviour characteristics.

Although limited in sample size, our data suggest no additional benefit of testing MG retrieved from MSM for macrolide resistance in Belgium, when making treatment decisions. The lower occurrence of macrolide resistance in other population groups, combined with emergence of fluoroquinolone RAMs support macrolide-resistance testing in these groups. Continued surveillance of resistance in MG in different population groups will be crucial to confirm our findings and to guide national testing and treatment strategies.

Diagnoses of bacterial sexually transmitted infections (STIs) have increased in France since the 2000s. The main strategy to control STI transmission is recommending/facilitating access to condom use, testing, and antibiotic treatments.

This study analyses the evolution of STI testing in the private sector in France from 2006 to 2020.

National health insurance reimbursement data were used to determine numbers and rates of individuals aged ≥ 15 years tested for diagnoses of chlamydia, gonorrhoea and syphilis in the private sector in France and to describe their evolution from 2006 to 2020.

Upward tendencies in testing were observed from 2006 to 2019 for all three STIs. The highest testing rates were identified in people aged 25‒29-years old. The observed testing-increase from 2017 to 2019 was twice as high in young people (< 25 years old) as in older people. In 2019, chlamydia, gonorrhoea and syphilis testing rates were respectively 45.4 (+ 21% since 2017), 41.3 (+ 60%), and 47.2 (+ 22%) per 1,000 inhabitants. For all STIs combined, the number of tested individuals decreased by 37% between March and April 2020 during the first COVID-19 epidemic wave and lockdown in France.

Improvements found in STI testing rates may have resulted from better awareness, especially among young people and health professionals, of the importance of testing, following prevention campaigns. Nevertheless, testing levels remain insufficient considering increasing diagnoses. In 2020, the COVID-19 pandemic had a considerable impact on STI testing. Partner notification and offering diverse testing opportunities including self-sampling are essential to control STI epidemics particularly in exposed populations.

Despite increased use of pre-exposure prophylaxis (PrEP) in Germany, HIV infection rates are not declining and little is known about how this prevention method affects the prevalence of sexually transmitted infections (STI) among men who have sex with men (MSM).

We studied, in a large multicentre cohort, STI point prevalence, co-infection rates, anatomical location and influence of PrEP.

The BRAHMS study was a prospective cohort study conducted at 10 sites in seven major German cities that enrolled MSM reporting increased sexual risk behaviour. At screening visits, MSM were tested for Mycoplasma genitalium (MG), Neisseria gonorrhoeae (NG), Chlamydia trachomatis (CT) and Treponema pallidum (TP), and given a behavioural questionnaire. With binomial regression, we estimated prevalence ratios (PR) and 95% confidence intervals (CI) for the association of PrEP and STI.

We screened 1,043 MSM in 2018 and 2019, with 53.0% currently using PrEP. At screening, 370 participants (35.5%) had an STI. The most common pathogen was MG in 198 (19.0%) participants, followed by CT (n = 133; 12.8%), NG (n = 105; 10.1%) and TP (n = 37; 3.5%). Among the 370 participants with at least one STI, 14.6% (n = 54) reported STI-related symptoms. Infection prevalence was highest at anorectal site (13.4% MG, 6.5% NG, 10.2% CT). PrEP use was not statistically significant in adjusted models for STI (PR: 1.10; 95% CI: 0.91–1.32), NG/CT, only NG or only CT.

Prevalence of asymptomatic STI was high, and PrEP use did not influence STI prevalence in MSM eligible for PrEP according to national guidelines.

To inform prevention and control of sexually transmitted infections (STIs), we need reliable prevalence estimates.

One objective of the Slovenian National Survey of Sexual Lifestyles, Attitudes and Health was to estimate the prevalence of STIs with Chlamydia trachomatis, Neisseria gonorrhoeae, Mycoplasma genitalium and Trichomonas vaginalis.

Data were collected between October 2016 and July 2017 in a probability sample of the general population aged 18–49 years. Computer-assisted face-to-face interviewing and self-completion of questionnaires were used. Respondents were invited to provide urine samples to be tested for STIs.

Of 1,929 survey participants, 1,087 individuals provided urine samples which were tested confidentially for C. trachomatis and a subset (n = 1,023) were tested anonymously for the other STIs. The prevalence of C. trachomatis was 0.5% (95% confidence interval (CI): 0.1–1.8) in men and 1.7% (95% CI: 0.9–3.2) in women. Age-specific prevalence was the highest among individuals aged 18–24 years, 2.8% (95% CI: 0.7–10.6) in men and 4.7% (95% CI: 1.7–12.3) in women. N. gonorrhoea was not detected. Prevalence of M. genitalium was 0.5% (95% CI: 0.1–2.2) in men and 0.3% (95% CI: 0.1–1.1) in women; the highest prevalence was among men aged 25–34 years (1.1%; 95% CI: 0.2–7.5) and women aged 35–49 years (0.5%; 95% CI: 0.1–2.0). T. vaginalis was detected in the sample from one woman (0.2%; 95% CI: 0.1–1.2).

The substantial prevalence of C. trachomatis among young adults suggests gaps in testing, diagnosis and treatment.