Emergence of the lymphogranuloma venereum L2c genovariant, Hungary, 2012 to 2016

STIs during the COVID-19 Pandemic in Hungary: Gonorrhea as a Potential Indicator of Sexual Behavior

The social distancing measures introduced due to the COVID-19 pandemic may have affected the sexual behavior of the population. We collected data retrospectively from the National STD Center of Hungary. The overall patient influx data of the STD Center and the number of patients diagnosed with syphilis, chlamydia, and gonorrhea infections were assessed in the three-month period of 2020 when the strict governmental lockdown was introduced in Hungary. Data were compared to the pre- and post-lockdown quarters of 2020 and matched to the respective quarters of 2018 and 2019. The number of patients diagnosed with syphilis and chlamydia infections in 2020 during the lockdown decreased compared to 2018 and 2019, while the number of gonorrhea cases increased. The lower number of STI screenings resulted in a significant decrease in asymptomatic syphilis and chlamydia case numbers. However, the growing number of gonorrhea cases in 2020 during lockdown highlights that sexual behavior remained unchanged regardless of restrictions. Therefore, gonorrhea may be considered as an indicator of STI incidences during the pandemic.

Prevalence of anatomically specific infections with Chlamydia trachomatis among men who have sex with men in China: protocol for a nationwide cross-sectional study as part of Disease Burden Surveillance of Infections with Chlamydia (DBSIC)

INTRODUCTION

Chlamydia trachomatis (CT) causes the most prevalent bacterial sexually transmitted infection in the world, and men who have sex with men (MSM) are considered as a high-risk population for this infection. Data regarding the prevalence of CT infection in China are limited and fragmented. In this study, we aim to determine at the national level the anatomically specific CT prevalence and genotype distribution of CT strains among MSM, recruiting from the venues where MSM commonly seek sexual partners.

METHODS AND ANALYSIS

The study will be a nationwide cross-sectional survey to estimate the prevalence of chlamydial infections among MSM who meet the inclusion criteria over a period of 6 months (May-October 2022). A total of 2429 participants will be recruited from the venues where MSM most often seek sex partners in 14 cities of the 7 geographical regions in China. A mobile phone app-based anonymous self-administered questionnaire will be used to collect sociodemographic and behavioural data, and specimens of urine, anorectal and pharyngeal swabs will be collected for identifying the infections of CT and Neisseria gonorrhoeae and genotypes of CT. The data will be analysed using the IBM SPSS program V.20 ETHICS AND DISSEMINATION: The study protocol has been approved by the Medical Ethics Committee of the Chinese Academy of Medical Sciences Institute of Dermatology and the National Center for STD Control on 9 October 2021 (approval number 2021-KY-037). The study is based on voluntary participation and a written informed consent process. The study results will be submitted for publication in peer-reviewed journals and reported in conferences. The relevant data will be made available to development of control programmes and used as health education materials to disseminate to the community. The dataset will be deposited in a public repository.

TRIAL REGISTRATION NUMBER

ChiCTR2100052869.

Ongoing evolution of Chlamydia trachomatis lymphogranuloma venereum: exploring the genomic diversity of circulating strains

Lymphogranuloma venereum (LGV), the invasive infection of the sexually transmissible infection (STI) Chlamydia trachomatis, is caused by strains from the LGV biovar, most commonly represented by ompA-genotypes L2b and L2. We investigated the diversity in LGV samples across an international collection over seven years using typing and genome sequencing. LGV-positive samples (n=321) from eight countries collected between 2011 and 2017 (Spain n=97, Netherlands n=67, Switzerland n=64, Australia n=53, Sweden n=37, Hungary n=31, Czechia n=30, Slovenia n=10) were genotyped for pmpH and ompA variants. All were found to contain the 9 bp insertion in the pmpH gene, previously associated with ompA-genotype L2b. However, analysis of the ompA gene shows ompA-genotype L2b (n=83), ompA-genotype L2 (n=180) and several variants of these (n=52; 12 variant types), as well as other/mixed ompA-genotypes (n=6). To elucidate the genomic diversity, whole genome sequencing (WGS) was performed from selected samples using SureSelect target enrichment, resulting in 42 genomes, covering a diversity of ompA-genotypes and representing most of the countries sampled. A phylogeny of these data clearly shows that these ompA-genotypes derive from an ompA-genotype L2b ancestor, carrying up to eight SNPs per isolate. SNPs within ompA are overrepresented among genomic changes in these samples, each of which results in an amino acid change in the variable domains of OmpA (major outer membrane protein, MOMP). A reversion to ompA-genotype L2 with the L2b genomic backbone is commonly seen. The wide diversity of ompA-genotypes found in these recent LGV samples indicates that this gene is under immunological selection. Our results suggest that the ompA-genotype L2b genomic backbone is the dominant strain circulating and evolving particularly in men who have sex with men (MSM) populations.

Lymphogranuloma venereum genovariants in men having sex with men in Italy

Objectives

Lymphogranuloma venereum (LGV) is an STI caused by Chlamydia trachomatis serovars L1-L3. In Europe, the current epidemic is caused mainly by L2b genovariant, although increasing cases associated with other L2 variants have been reported. Here, we assessed the distribution of rectal LGV genovariants among men having sex with men (MSM) in Italy.

Methods

From 2016 to 2020, all the anorectal swabs collected from MSM attending the STI Clinic of St. Orsola-Malpighi Hospital in Bologna and positive for C. trachomatis were stored. LGV infection was confirmed by a pmpH PCR, and, subsequently, a fragment of the ompA gene was amplified and sequenced. Sequences were aligned to reference strains representing different LGV variants.

Results

LGV cases accounted for one-third of all chlamydial rectal infections with a total prevalence of 4.1% (76/1852). Total number of LGV cases per year remained constant. LGV was mainly found in symptomatic patients (>65%), older than 30 years, with a high burden of other STIs (63.7% HIV-positive, 35.5% with concurrent rectal gonorrhoea, 19.7% with early syphilis). A decreasing trend in HIV-LGV co-infection was noticed over time. Three main LGV genovariants were detected (L2f, 46.1%; L2b, 23.0%; L2-L2b/D-Da, 16.9%), together with other known L2b variants (mainly L2bV2 and L2bV4). Two novel L2b ompA variants with non-synonymous single-nucleotide polymorphisms were found. Over time, the percentage of L2f cases dropped gradually, with a significant increase in L2-L2b/D-Da cases (p=0.04).

Conclusions

In our area, LGV is endemic among MSM with different circulating genovariants. Active surveillance and genotyping programmes are needed to reduce re-establishing of LGV infection.

Substantial underdiagnosis of lymphogranuloma venereum in men who have sex with men in Europe: preliminary findings from a multicentre surveillance pilot

Objectives

Understanding the public health impact of lymphogranuloma venereum (LGV) in Europe is hampered by inadequate diagnostics and surveillance systems in many European countries. We developed and piloted LGV surveillance in three European countries without existing systems and performed a preliminary investigation of LGV epidemiology, where little evidence currently exists.

Methods

We recruited STI or dermatovenereology clinics and associated laboratories serving men who have sex with men (MSM) in Austria, Croatia and Slovenia, using the UK for comparison. We undertook centralised LGV testing of Chlamydia trachomatis (CT)-positive rectal swabs collected between October 2016 and May 2017 from MSM attending these clinics. Stored specimens from Austria (2015–2016) and Croatia (2014) were also tested. Clinical and sociodemographic data were collected using a standardised proforma. The ompA gene of LGV-positive specimens was sequenced.

Results

In total, 500 specimens from CT-positive MSM were tested, and LGV positivity was 25.6% (128/500; 95% CI 22.0% to 29.6%) overall, and 47.6% (79/166; 40.1% to 55.2%) in Austria, 20.0% (3/15; 7.1% to 45.2%) in Croatia, 16.7% (1/6; 3.0% to 56.4%) in Slovenia and 14.4% (45/313; 10.9% to 18.7 %) in the UK. Proformas were completed for cases in Croatia, Slovenia and in the UK; proformas could not be completed for Austrian cases, but limited data were available from line listings. Where recorded, 83.9% (78/93) of LGV-CT cases were HIV-positive compared with 65.4% (149/228) of non-LGV-CT cases; MSM with LGV-CT were more likely to have proctitis (Austria, 91.8% vs 40.5%, p<0.001; Croatia, 100% vs 25%, p=0.04; UK, 52.4% vs 11.7%, p<0.001) than those with non-LGV-CT. Six different ompA sequences were identified, including three new variants; the L2 ompA sequence predominated (58.6%, 51/87).

Conclusions

LGV is substantially underdiagnosed in MSM across Europe. Unified efforts are needed to overcome barriers to testing, establish effective surveillance, and optimise diagnosis, treatment and prevention.

Unveiling the Multilocus Sequence Typing (MLST) Schemes and Core Genome Phylogenies for Genotyping Chlamydia trachomatis

Multilocus sequence typing (MLST) has become a useful tool for studying the genetic diversity of important public health pathogens, such as Chlamydia trachomatis (Ct). Four MLST schemes have been proposed for Ct (data available from Chlamydiales MLST databases). However, the lack of a sole standardized scheme represents the greatest limitation regarding typing this species. This study was thus aimed at evaluating the usefulness of the four MLST schemes available for Ct, describing each molecular marker's pattern and its contribution toward a description of intra-specific genetic diversity and population structure. The markers for each scheme, showed a variable power of dicrimination, exhibiting in some cases over estimation in the determination of Sequence Types (STs). However, individual analysis of each locus's typing efficiency and discrimination power led to identifying 8 markers as having a suitable pattern for intra-specific typing. analyzing the 8 candidate markers gave a combination of 3 of these loci as an optimal scheme for identifying a large amount of STs, maximizing discrimination power whilst maintaining suitable typing efficiency. One scheme was compared against core genome phylogenies, finding a higher typing resolution through the last approach. These results confirm once again that although complete genome data, in particular from core genome MLST (cgMLST) allow a high resolution clustering for Ct isolates. There are combinations of molecular markers that could generate equivalent results, with the advantage of representing an easy implementation strategy and lower costs leading to contribute to the monitoring and molecular epidemiology of Ct.

[Diagnostic issues of lymphogranuloma venereum: A case series of 5 patients]

INTRODUCTION

Lymphogranuloma venereum (LG) is a sexually transmitted infection (STI) caused by Chlamydia trachomatis L serovar.

METHODS

These five consecutive cases aim to highlight the risk of LG misdiagnosis, in case of initial presentation with isolated inguinal adenitis.

RESULTS

Five men (mean age: 30±7 years) were seen in an internal medicine department, for inguinal adenopathy. One patient had clinical signs of urethritis. None presented an associated rectitis. Three patients had a history of STI, and two had a discovery of related HIV disease. Urinary polymerase chain reaction (PCR) was positive for the symptomatic patient and negative for the others. Lymph node PCR was positive in all patients within a L2b serotype (searched in 4 out of 5 cases).

CONCLUSION

LG should be evoked in any patient with inguinal adenomegaly, particularly in case of STI history or risk factors. Negativity of urinary PCR should lead to further investigations, essentially a lymph node cytopuncture to evidence C. trachomatis.