Syphilis incidence among men who have sex with men in China: results from a meta-analysis

In-Depth Proteome Coverage of In Vitro-Cultured Treponema pallidum and Quantitative Comparison Analyses with In Vivo-Grown Treponemes

Previous mass spectrometry (MS)-based global proteomics studies have detected a combined total of 86% of all Treponema pallidum proteins under infection conditions (in vivo-grown T. pallidum). Recently, a method was developed for the long-term culture of T. pallidum under in vitro conditions (in vitro-cultured T. pallidum). Herein, we used our previously reported optimized MS-based proteomics approach to characterize the T. pallidum global protein expression profile under in vitro culture conditions. These analyses provided a proteome coverage of 94%, which extends the combined T. pallidum proteome coverage from the previously reported 86% to a new combined total of 95%. This study provides a more complete understanding of the protein repertoire of T. pallidum. Further, comparison of the in vitro-expressed proteome with the previously determined in vivo-expressed proteome identifies only a few proteomic changes between the two growth conditions, reinforcing the suitability of in vitro-cultured T. pallidum as an alternative to rabbit-based treponemal growth. The MS proteomics data have been deposited in the MassIVE repository with the data set identifier MSV000093603 (ProteomeXchange identifier PXD047625).

Deep proteome coverage advances knowledge of Treponema pallidum protein expression profiles during infection

Comprehensive proteome-wide analysis of the syphilis spirochete, Treponema pallidum ssp. pallidum, is technically challenging due to high sample complexity, difficulties with obtaining sufficient quantities of bacteria for analysis, and the inherent fragility of the T. pallidum cell envelope which further complicates proteomic identification of rare T. pallidum outer membrane proteins (OMPs). The main aim of the present study was to gain a deeper understanding of the T. pallidum global proteome expression profile under infection conditions. This will corroborate and extend genome annotations, identify protein modifications that are unable to be predicted at the genomic or transcriptomic levels, and provide a foundational knowledge of the T. pallidum protein expression repertoire. Here we describe the optimization of a T. pallidum-specific sample preparation workflow and mass spectrometry-based proteomics pipeline which allowed for the detection of 77% of the T. pallidum protein repertoire under infection conditions. When combined with prior studies, this brings the overall coverage of the T. pallidum proteome to almost 90%. These investigations identified 27 known/predicted OMPs, including potential vaccine candidates, and detected expression of 11 potential OMPs under infection conditions for the first time. The optimized pipeline provides a robust and reproducible workflow for investigating T. pallidum protein expression during infection. Importantly, the combined results provide the deepest coverage of the T. pallidum proteome to date.

Immunization with Tp0954, an adhesin of Treponema pallidum, provides protective efficacy in the rabbit model of experimental syphilis

Syphilis, a chronic multisystemic disease caused by spirochete Treponema pallidum subspecies pallidum infection, continues to be a serious global health problem and congenital syphilis remains a major cause of adverse outcomes in pregnancy in developing countries. The development of an effective vaccine is the most cost-effective way to eliminate syphilis, but so far has been elusive. Here, we evaluated the immunogenicity and protective efficacy of Tp0954, a T. pallidum placental adhesin, as a potential vaccine candidate in a New Zealand White rabbit model of experimental syphilis. Animals immunized with recombinant Tp0954 (rTp0954) produced high titers of Tp0954-specific serum IgG, high levels of IFN-γ from splenocytes and specific splenocyte proliferation response when compared to control animals immunized with PBS and Freund’s adjuvant (FA). Furthermore, rTp0954 immunization significantly delayed the development of cutaneous lesions, promoted inflammatory cellular infiltration at the primary lesion sites, as well as inhibited T. pallidum dissemination to distal tissues or organs when compared with that of the control animals. In addition, the naïve rabbits receiving popliteal lymph nodes from Tp0954-immunized, T. pallidum-challenged animals were not infected by T. pallidum, confirming sterile immunity. These findings suggest that Tp0954 is a potential vaccine candidate against syphilis.

Prevalence of HIV and syphilis and their co-infection among men having sex with men in Asia: A systematic review and meta-analysis

Background

Studies found that the group of men who have sex with men (MSM) is at a very high level of risk of HIV and sexually transmitted infections (STIs) in Asian regions due to multiple reasons. Although the prevalence of HIV among general people in Asia is considered low, the prevalence of HIV and Syphilis among MSM in this region was found very high and usually, it goes unnoticed. This study aimed to inspect the prevalence of and trends in HIV, Syphilis, and their co-infection among MSM in Asia.

Methods

A systematic search was performed on January 5, 2021, in PubMed, Web of Science, and Google Scholar databases. To evaluate the heterogeneity, Q-tests, and I ² were used. To explore the publication bias, Eggers' test and funnel plot were used. The random-effect model and subgroup analysis were performed due to the significant heterogeneity.

Results

A total of 2872 articles were identified, and 66 articles were included in the final analysis. The overall prevalence of HIV and Syphilis among MSM was estimated considering 69 estimates from 66 studies whereas 19 estimates of co-infection were found in 17 studies. The pooled HIV prevalence was 8.48% (CI: 7.01-9.95) and the pooled Syphilis prevalence was 9.86% (CI: 8.30-11.41) with significant heterogeneity and publication bias. The pooled prevalence of HIV and Syphilis co-infection was 2.99% (CI: 1.70-4.27) with significant heterogeneity and no publication bias. The HIV, Syphilis, and HIV-Syphilis co-infection prevalence estimates exhibited an upward trend during 2002-2017.

Conclusions

HIV, Syphilis, and their co-infection are quite prevalent among MSM in the Asia-Pacific region. Integrated and intensified intervention strategies, HIV testing, and improved access to antiretroviral treatment as well as increased awareness are needed to reduce HIV, Syphilis, and their co-infection among the discussed vulnerable group.

Optimizing Peer Distribution of Syphilis Self-Testing Among Men Who Have Sex with Men in China: A Multi-City Pragmatic Randomized Controlled Trial

Syphilis testing uptake is low among men who have sex with men (MSM) around the world. Syphilis self-testing (SST) may complement facility-based testing; the distribution model is yet to be explored. This study aimed to investigate the effectiveness of peer distribution of syphilis self-testing on promoting syphilis testing. We conducted a three-arm, unblinded, parallel individually randomized controlled trial among MSM in three cities in Guangdong, China. Inclusion criteria were: men who were born biologically male, aged 18 or above, have ever had sex with a man, will refer the interventions to peers, and will take the three-month follow-up survey. Enrolled indexes were randomly assigned in a 1:1:1 ratio into standard-of-care arm (SOC arm), standard SST delivery arm (S-SST arm), and a web-based referral link SST delivery arm (RL-SST arm). The primary outcome was the number of returned photograph-verified syphilis testing results per index. A total number of 300 indexes were enrolled, with 100 indexes in each arm. The number of verified syphilis tests per index conducted by alters was 0.05 in the control arm, 0.51 in the S-SST arm, and 0.31 in the RL-SST arm. The cost per alter tested was $760.60 for SOC, $83.78 for S-SST, and $93.10 for RL-SST. Minimal adverse event was reported among both indexes and alters during the study. This study showed that peer distribution of SST could improve syphilis testing uptake among MSM in China compared to facility-based testing. This approach warrants further consideration as part of expanding syphilis self-testing.

The Changing Trend of Syphilis: Is It a Sign of Impending Epidemic?

Background

Syphilis is a treatable bacterial infection caused by Treponema pallidum. There has been a change in incidence of syphilis in various nations over the years.

Aim

To study the epidemiological trends, demographic profile, high-risk behaviour, clinical pattern, and stage of syphilis over the last ten years in patients presenting to an STD clinic in a tertiary care hospital.

Material and Methods

This was a retrospective observational study over ten years. Records of all confirmed syphilis cases were analysed in relation to demography and clinical profile.

Results

There were a total of 3,110 STD patients among whom 31 cases (accounting for 0.99%) of confirmed syphilis were seen. There was a significant increase in cases in the last five years of study, especially in the last year. An increase in primary (PS) and secondary syphilis (SS) was observed. Males outnumbered females (3:1). Mean age of patients was 35.0 ± 11.53 years. Professionals were most common (22.6%) having syphilis followed by farmers (19.35%). A significant proportion (45.1%) of our patients were at least graduates. Unprotected sex was seen in all the patients followed by extramarital/premarital sex (71.35%). There were 16.12% of cases who had a history of paid sex and 9.7% were homosexuals. SS and latent syphilis were more common (38.7% each) than PS (19.35%). In PS single chancre and in SS truncal asymptomatic rash was the commonest clinical presentation. Limitation: Single-centre study, including only self-reported patients leading to a small sample size, is the major limitation of the study.

Conclusion

The increased trend of primary and secondary syphilis in recent years highlights that there is a risk of an impending epidemic.

Prevalence of syphilis and chlamydia trachomatis infection among men who have sex with men in Jiangsu province, China: A cross-sectional survey

Background

Epidemics of sexually transmitted infections (STIs) among men who have sex with men (MSM) are major global public health concerns. This study aimed to examine the prevalence of syphilis and chlamydia trachomatis (CT) infection and associated factors among MSM in Jiangsu province, China, hoping to provide updated data for the formulation of relevant policies.

Methods

A cross-sectional survey was conducted among MSM from April to July 2021 in four cities in the province. Socio-demographic characteristics and behavioral information were collected through a face-to-face questionnaire interview. Venous blood specimens were collected for HIV, hepatitis C (HCV), and syphilis testing using serological testing methods. First-void urine specimens were collected for CT and Neisseria gonorrhoeae (NG) testing using nucleic acid amplification testing (NAAT) methods. Chi-square tests were used to compare differences in syphilis and CT infection between subgroups of variables. Multivariate logistic regression analysis was used to identify factors associated with syphilis and CT infection.

Results

A total of 1,087 participants were enrolled. The prevalence of HIV, HCV, syphilis, CT and NG infection were 6.6, 0.4, 6.3, 4.2, and 0.4%, respectively. MSM recruited online [adjusted odds ratio (aOR) = 2.189, P = 0.020], diagnosed with an STI in the past 12 months (aOR = 3.304, P < 0.001), and living with HIV (aOR = 4.721, P < 0.001) were more likely to have syphilis infection. MSM who were younger than 25 years (aOR = 4.286, P = 0.020), had senior high school level education (aOR = 2.521, P = 0.038), and were recruited via VCT clinics (aOR = 3.455, P = 0.001) were more likely to have CT infection.

Conclusions

Our study showed a high prevalence of syphilis and chlamydia among MSM in Jiangsu province, China. STI screening, diagnosis, and treatment services promotion should be a top priority on the prevention agenda.

Incidence and risk factors for syphilis infection among men who have sex with men: A cohort study from an urban sexual health clinic in Jakarta, Indonesia

Objective: Syphilis infection remains a significant health issue among marginalised populations in Indonesia, in particular among men who have sex with men (MSM), in whom there are limited studies from Indonesia exploring risk factors associated with STI acquisition.Our study aimed to identify risk factors of syphilis infection among MSM attending large sexual health clinic in Jakarta. Methods: We conducted a retrospective cohort analysis using patient records (MSM aged 18 years or older) period Jan 2018-Dec 2019. We used Cox regression to identify risk factors associated with syphilis incidence. Results: Study population were 2912 MSM tested for syphilis, 473 (16.2%) were diagnosed with syphilis on their first visit; early syphilis (415; 14%) and latent syphilis (58, 2%). Among the cohort of 2439 MSM who tested negative at baseline, 40 MSM were identified with a new positive syphilis result during 2 years follow up. Risk factors remaining significantly associated with syphilis incidence included having STI symptom at 1st visit (aHR, 2.8; 95% CI, 1.38-5.65), and HIV-infection (aHR 4.53; 95% CI 2.24 - 9.17).Syphilis incidence rate was 8.19 (95% CI 6.01-11.16) per 100 PYFU. Conclusions: Syphilis infection at baseline and incidence was high among MSM attending this large clinic in Jakarta. Integrated and accessible syphilis prevention and detection coupled with HIV services are needed, with a special focus on high-risk individuals.

Coerced syphilis self-testing among men who have sex with men: a nationwide cross-sectional study in China

BACKGROUND

Syphilis testing uptake remains low among men who have sex with men (MSM) in many low-and middle-income countries. Syphilis self-testing is an efficacious approach on increasing syphilis testing coverage. However, one unintended consequence is the syphilis self-testing coercion from others (including partners, healthcare providers, friends, etc.). This study aimed to examine the prevalence, pattern and correlates of coerced syphilis self-testing among MSM in China.

METHODS

A nationwide online cross-sectional study was conducted from 14 to 28 July 2018. Sociodemographic characteristics, sexual behaviors and coerced syphilis self-testing variables were collected through a questionnaire that targeted MSM in China. Multivariable logistic regression was used to explore associated factors with syphilis self-testing coercion.

RESULTS

Overall, 174 MSM were recruited in this study, 31 men (17.8%) reported ever experiencing syphilis self-testing coercion. The most common types of coercion before syphilis self-testing were verbal abuse (38.7%, 12/31) and threatening to end a relationship (38.7%, 12/31). After obtaining the self-test results, men were mostly subjected to end a relationship (45.2%, 14/31) and threaten of violence (35.5%, 11/31). Multivariable logistic regression indicated that men who used condoms inconsistently in the past three months, ever used substances before or during sex, ever had group sex with males and commercial sex were more likely to experience syphilis self-testing coercion.

CONCLUSIONS

Coerced syphilis self-testing was prevalent among MSM in China. Innovative intervention to reduce coerced syphilis self-testing is necessary among MSM in China.

Factors Associated With Neurosyphilis in Patients With Syphilis Treatment Failure: A Retrospective Study of 165 HIV-Negative Patients

Background

In recent years, the incidence of syphilis has increased year by year. Our study is to explore the risk factors for the development of neurosyphilis in patients who failed syphilis treatment.

Methods

A total number of 165 patients with complete medical records and who agreed to undergo lumbar puncture were divided into 47 neurosyphilis cases and 118 non-neurosyphilis cases according to the diagnostic criteria of neurosyphilis, and the differences in clinical characteristics and laboratory features between the two groups were analyzed. Significant variables were entered into multivariable logistic regression models.

Results

(1) There were statistical differences (p < 0.05) between the neurosyphilis (NS) group and the non-neurosyphilis (NNS) group in terms of the higher proportion of male and serum rapid plasma reagin (RPR) > 1:32 and the elevated cerebrospinal fluid white blood cell (CSF WBC) and CSF protein in the neurosyphilis group compared with the non-neurosyphilis group. (2) Male gender, serum RPR titers >1:32 at lumbar puncture, CSF WBC >8 × 10⁶/L were significantly associated with neurosyphilis.

Conclusion

For patients who have failed syphilis treatment, lumbar puncture should be performed to exclude neurosyphilis, to enable early diagnosis and treatment, and to prevent irreversible damage of neurosyphilis, especially if the patient is male and has a serum RPR>1:32 and elevated CSF WBC at lumbar puncture, which are risk factors for neurosyphilis.

Two Potential Syphilis Vaccine Candidates Inhibit Dissemination of Treponema pallidum

Syphilis, caused by the spirochete Treponema pallidum subspecies pallidum, continues to be a major public health problem worldwide. Recent increases in the number of syphilis cases, in addition to the lack of an efficient vaccine against T. pallidum for humans, highlights an urgent need for the design and development of an efficacious syphilis vaccine. Here, we assess the vaccine potential of the adhesion protein Tp0136 and the outer membrane protein Tp0663. Rabbits were subcutaneously immunized with recombinant proteins Tp0136, Tp0663, or control PBS. Immunization with Tp0136 or Tp0663 generated a strong humoral immune response with high titers of IgG, as assessed by ELISA. Moreover, animals immunized with Tp0136 or Tp0663 exhibited attenuated lesion development, increased cellular infiltration at the lesion sites, and inhibition of treponemal dissemination to distant organs compared to the unimmunized animals. These findings indicate that Tp0136 and Tp0663 are promising syphilis vaccine candidates. Furthermore, these results provide novel and important information for not only understanding the pathogenic mechanisms of spirochetes, but also the development of spirochete-specific subunit vaccines.

Simple-to-use nomogram for predicting the risk of syphilis among MSM in Guangdong Province: results from a serial cross-sectional study

Background

The purpose of this study was to develop and validate a simple-to-use nomogram for the prediction of syphilis infection among men who have sex with men (MSM) in Guangdong Province.

Methods

A serial cross-sectional data of 2184 MSM from 2017 to 2019 was used to develop and validate the nomogram risk assessment model. The eligible MSM were randomly assigned to the training and validation dataset. Factors included in the nomogram were determined by multivariate logistic regression analysis based on the training dataset. The receiver operating characteristic (ROC) curves was used to assess its predictive accuracy and discriminative ability.

Results

A total of 2184 MSM were recruited in this study. The prevalence of syphilis was 18.1% (396/2184). Multivariate logistic analysis found that age, the main venue used to find sexual partners, condom use in the past 6 months, commercial sex in the past 6 months, infection with sexually transmitted diseases (STD) in the past year were associated with syphilis infection using the training dataset. All these factors were included in the nomogram model that was well calibrated. The C-index was 0.80 (95% CI 0.76–0.84) in the training dataset, and 0.79 (95% CI 0.75–0.84) in the validation dataset.

Conclusions

A simple-to-use nomogram for predicting the risk of syphilis has been developed and validated among MSM in Guangdong Province. The proposed nomogram shows good assessment performance.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12879-021-06912-z.

The Holistic Health Status of Chinese Homosexual and Bisexual Adults: A Scoping Review

Background: Same-sex marriage is currently not legalized in China, despite the considerably large number of homosexual and bisexual Chinese populations. At the same time, their holistic health status remains unclear. This is the first scoping review conducted to comprehensively examine all the available literature and map existing evidence on the holistic health of homosexual and bisexual Chinese. Methods: This scoping review used the framework of Arksey and O'Malley and followed the Preferred Reporting Items for Systematic Review and Meta-Analysis extension for scoping reviews (PRISMA-ScR). A comprehensive search strategy was carried out across 20 English (EN) and Chinese (both traditional and simplified) electronic databases from January 1, 2001, to May 31, 2020. Two reviewers conducted the reference screening and study selection independently and consulted a third senior reviewer whenever a consensus must be achieved. Data extraction was conducted using a structured data form based on the Cochrane template, after which a narrative synthesis of the findings was performed. Results: A total of 2,879 references were included in the final analysis, with 2,478 research articles, 167 reviews, and 234 theses. Regarding the study populations, the vast majority of studies centered on men only (96.46%), especially men who have sex with men (MSM). Only 1.32% of the studies targeted female sexual minorities. The geographical distribution of all research sites was uneven, with most of them being conducted in mainland China (95.96%), followed by Hong Kong (2.05%), Taiwan (2.02%), and Macau (0.06%). Regarding the specific study focus in terms of the health domain, around half of the studies (45.93%) focused on sexual health only, and an additional quarter of the studies (24.15%) investigated both sexual health and social well-being. Meanwhile, the studies focusing on mental health only accounted for approximately 15% of the total. Conclusions: This scoping review revealed that previous research focused more on male than female sexual minorities, on disease-centered surveys than person-centered interventions, and investigations on negative health conditions than positive health promotion. Therefore, investigations centered on the female sexual minorities and corresponding person-centered interventions are highly needed. Review Registration: The protocol of this review has been registered within Open Science Framework (https://osf.io/82r7z) on April 27, 2020.

Epidemiological characteristics and trends of notifiable infectious diseases in China from 1986 to 2016

Background

Since the 1980s, China has undergone significant social change and the incidence of infectious diseases has also changed considerably. Here, we report the epidemiological features and changes in notifiable infectious diseases in China from 1986 to 2016 to explore the factors contributing to the successful control of infectious diseases and the challenges faced in the prevention and control of infectious diseases.

Methods

The data of notifiable infectious diseases in China from 1986 to 2016 were collected from the monthly analysis report of the National Infectious Disease Surveillance System. Joinpoint regression models were used to examine incidence and mortality trends from 1986 to 2016. IBM SPSS Statistics version 22.0, Excel 2010 and R x64 3.5.2 were used for data analysis.

Results

A total of 132 858 005 cases of notifiable infectious diseases were reported over these 31 years, with an average yearly incidence of 342.14/100 000. There were 284 694 deaths with an average yearly mortality rate of 0.73/100 000. The overall incidence and overall mortality of notifiable infectious diseases both showed a "U" distribution (ie, a decrease, stable, an increase, stable again). The top five diseases in terms of incidence were hand, foot and mouth disease, viral hepatitis, tuberculosis, other infectious causes of diarrhea and dysentery, accounting for 78.0% of all reported cases. The top five causes of death were HIV/AIDS, rabies, tuberculosis, viral hepatitis and epidemic encephalitis B, which accounted for 76.07% of all mortalities. The diseases with the top five fatality rates were rabies, H5N1, H7N9, HIV/AIDS and plague, with rates of 91.06%, 66.07%, 38.51%, 25.19% and 10.31%, respectively.

Conclusions

This analysis will benefit the future monitoring of infectious diseases and public health measures in China.

The Intersection of HIV and Syphilis: Update on the Key Considerations in Testing and Management

PURPOSE OF REVIEW

To highlight recent trends in the epidemiology of HIV and syphilis, the impact of the COVID epidemic, our approach to care of co-infected patients, and our views on important next steps in advancing the field.

RECENT FINDINGS

HIV and syphilis co-infection has been on the rise in recent years although since the COVID pandemic there is a decrease in new diagnoses-it remains unclear if this represents a true decline or inadequate testing or under-reporting. Standard HIV care should include regular syphilis serology .Treatment and serological follow-up of syphilis in HIV positive and negative patients can be conducted similarly. Challenges remain in the diagnosis and management of neurosyphilis. New models for testing and prevention will be crucial next steps in controlling co-infection. The intersection of HIV and syphilis infections continues to pose new and unique challenges in diagnosis, treatment, and prevention.

Social network distribution of syphilis self-testing among men who have sex with men in China: study protocol for a cluster randomized control trial

BACKGROUND

Syphilis is a common sexually transmitted infection (STI) among men who have sex with men (MSM). Increasing syphilis testing is important to syphilis control. However, in low- and middle-income countries like China, syphilis testing rates remain low among MSM. We describe a randomized controlled trial protocol to examine the effectiveness of social network distribution approaches of syphilis self-testing among MSM in China.

METHODS

We will recruit index and alter MSM. Indexes will be eligible if they: are born biologically male; aged 18 years or above; ever had sex with another man; are willing to distribute syphilis testing packages or referral links to their alters; and willing to provide personal contact information for future follow-up. Three hundred MSM will be recruited and randomly assigned in a 1:1:1 ratio into three arms: standard of care (control arm); standard syphilis self-testing (SST) delivery arm; and referral link SST delivery arm. Indexes will distribute SST packages or referral links to encourage alters to receive syphilis testing. All indexes will complete a baseline survey and a 3-month follow-up survey. Syphilis self-test results will be determined by photo verification via a digital platform. The primary outcome is the mean number of alters who returned verified syphilis testing results per index in each arm.

DISCUSSION

The trial findings will provide practical implications in strengthening syphilis self-testing distribution and increasing syphilis testing uptake among MSM in China. This study also empowers MSM community in expanding syphilis testing by using their own social network.

TRIAL REGISTRATION

Chinese Clinical Trial Registry, ChiCTR2000036988 . Registered 26 August 2020 - Retrospectively registered.

Syphilis Self-testing: A Nationwide Pragmatic Study Among Men Who Have Sex With Men in China

BACKGROUND

Syphilis self-testing may help expand syphilis testing among men who have sex with men (MSM). China has rapidly scaled up human immunodeficiency virus (HIV) self-testing, creating an opportunity for integrated syphilis self-testing. However, there is a limited literature on implementing syphilis self-testing.

METHODS

A cross-sectional online survey was conducted among Chinese MSM in 2018. Participants completed a survey instrument including sociodemographic characteristics, sexual behaviors, syphilis self-testing, and HIV self-testing history. Multivariable logistic regression was conducted to identify correlates of syphilis self-testing. We also recorded potential harms associated with syphilis self-testing.

RESULTS

Six hundred ninety-nine MSM from 89 cities in 21 provinces in China completed the study. A total of 361/699 (51.7%) men tested for syphilis, of whom 174/699 (24.9%) men used syphilis self-testing. Among 174 who had self-tested, 90 (51.7%) reported that the self-test was their first syphilis test and 161 (92.5%) reported that they undertook syphilis self-testing together with HIV self-testing. After adjusting for covariates, syphilis self-testing was correlated with disclosure of sexual orientation to family or friends (adjusted odds ratio [aOR], 1.90; 95% confidence interval [CI], 1.32-2.73), reporting 2-5 male sexual partners (aOR, 1.81; 95% CI, 1.04-3.16), HIV self-testing (aOR, 39.90; 95% CI, 17.00-93.61), and never tested for syphilis in the hospital (aOR, 2.96; 95% CI, 1.86-4.72). Self-reported harms associated with syphilis self-testing were minimal.

CONCLUSIONS

Scaling up syphilis self-testing could complement facility-based testing in China among MSM. Self-testing may increase first-time testing and has limited harms. Our findings suggest that syphilis self-testing could be integrated into HIV self-testing services.

HIV and other STIs self-testing to reduce risk compensation among men who have sex with men who use oral pre-exposure prophylaxis in China: protocol for a randomised waitlist-controlled trial

INTRODUCTION

Pre-exposure prophylaxis (PrEP) reduces the risk of HIV infection among men who have sex with men by up to 99%. However, in real-world settings, PrEP users may exhibit risk compensation after uptake of PrEP, including more condomless anal intercourse (CAI) and increased sexually transmitted infection (STI) acquisition. HIV self-testing (HIVST) decreases CAI among men who have sex with men (MSM) by providing awareness of the HIV status of oneself and one's sexual partners. Here, we describe the rationale and design of a randomised waitlist-controlled trial to examine the impact of HIVST on risk compensation among PrEP users.

METHODS AND ANALYSIS

The study is a two-arm randomised waitlist-controlled trial with 1000 HIV-negative MSM in four major cities in China who will be taking oral PrEP (involving tenofovir disoproxil fumarate/emtricitabine) either daily (n=500) or in an event-driven regimen (n=500). The participants will be randomised (1:1) to either the immediate HIVST intervention arm (HIVST plus standard facility-based counselling and testing from 0 to 12 months) or the waitlist arm (standard facility-based counselling and testing from 0 to 6 months, then crossover to receive the HIVST intervention in months 7-12). Participants will provide blood samples to assess the incidence of syphilis and herpes simplex virus type 2 (HSV-2) during a follow-up. The primary outcomes will be the occurrence of CAI, number of sexual partners and incidence of syphilis and HSV-2 during a follow-up. The secondary outcomes will be the HIV and STI testing frequency and STI treatment adherence during a follow-up. The planned start and end dates for the study is 26 December 2018 and 31 December 2020.

ETHICS AND DISSEMINATION

The Medical Science Research Ethics Committee of The First Affiliated Hospital of China Medical University has approved the study (IRB(2018)273).

TRIAL REGISTRATION NUMBER

ChiCTR1800020374.

High HIV Incidence Among Men Who Have Sex With Men in 8 Chinese Cities: Results From a Trial

Background

In China, while the overall HIV prevalence has been decreasing within key populations, the epidemic among men who have sex with men (MSM) is still on the rise. This study aims to assess the HIV incidence rate and identify driving forces of HIV seroconversion among MSM in a closed cohort.

Methods

This study is a secondary analysis of a large trial of HIV testing promotion among Chinese MSM in 2016–2017. Sexual behaviors, HIV testing activities, and HIV serostatus were measured at baseline and follow-up every 3 months. HIV seroconversion in this study was defined as a self-reported HIV-positive test result. Participants who reported testing for HIV at least twice during different follow-up periods were included. Subgroup analysis and Cox regression were used to examine the correlates with HIV seroconversion.

Results

Overall, 347 participants were included in this study, with a mean age of 25.3 ± 6.1, and 71.2% were migrants. The sociodemographic characteristics of the included participants were similar to the rest of the participants in the trial (n = 1034); 7.2% (25/347) of participants seroconverted during the study period, resulting in an incidence rate of 15.56/100 person-years. In subgroup analysis, the HIV incidence rate was higher among migrants than nonmigrants (incidence rate ratio, 1.26; 95% confidence interval [CI], 0.47–3.87). In the time-dependent Cox regression model, bisexual MSM had a higher risk of contracting HIV than gay men (adjusted hazard ratio, 2.19; 95% CI, 1.02–4.72).

Conclusions

Our findings suggest a high HIV incidence rate among Chinese MSM. Further expansion of pre-exposure prophylaxis and other effective HIV prevention interventions are urgently needed.

Partner Notification Among Persons With Early Syphilis in Shenzhen, China, 2011-2017: Implications for Practice and Policy

BACKGROUND

Partner notification (PN) is an essential component of syphilis control and is recommended by Chinese Sexually Transmitted Disease guidelines. However, in China, studies examining local practice are limited. This study evaluated PN outcomes among persons with early syphilis infection in an urban district in China.

METHODS

From 2011 to 2017, persons diagnosed with early syphilis were asked to participate in an evaluation of supportive patient referral partner services for all recent sex partners, and the contact and case finding indices were determined in Nanshan District, Shenzhen, China.

RESULTS

During the study period, 642 index patients with early syphilis reported 1749 sex partners. Of those partners, 678 were potentially contactable and 525 (30%) were contacted. The overall contact index was 0.82. Among the 1749 partners reported, 1108 (63%) were described as casual partners, and only 37 (3%) were contacted (contact index 0.13) compared with 641 partners who were either spouses and regular partners (contact index, 1.37). Among those 525 partners contacted, 418 (80%) were tested, and 205 (39%) were diagnosed with and treated for syphilis. Among those, 9 (4%) were primary, 26 (13%) were secondary, 16 (8%) were early latent, and 154 (49%) were other syphilis infections. The overall case finding index was 0.29.

CONCLUSIONS

There is a need to improve PN practices in China, which include developing operational guidelines of PN and to develop and evaluate novel PN ways like using Internet-based strategy.

Identification of the Neuroinvasive Pathogen Host Target, LamR, as an Endothelial Receptor for the Treponema pallidum Adhesin Tp0751

Treponema pallidum subsp. pallidum is the causative agent of syphilis, a human-specific sexually transmitted infection that causes a multistage disease with diverse clinical manifestations. Treponema pallidum undergoes rapid vascular dissemination to penetrate tissue, placental, and blood-brain barriers and gain access to distant tissue sites. The rapidity and extent of T. pallidum dissemination are well documented, but the molecular mechanisms have yet to be fully elucidated. One protein that has been shown to play a role in treponemal dissemination is Tp0751, a T. pallidum adhesin that interacts with host components found within the vasculature and mediates bacterial adherence to endothelial cells under shear flow conditions. In this study, we further explore the molecular interactions of Tp0751-mediated adhesion to the vascular endothelium. We demonstrate that recombinant Tp0751 adheres to human endothelial cells of macrovascular and microvascular origin, including a cerebral brain microvascular endothelial cell line. Adhesion assays using recombinant Tp0751 N-terminal truncations reveal that endothelial binding is localized to the lipocalin fold-containing domain of the protein. We also confirm this interaction using live T. pallidum and show that spirochete attachment to endothelial monolayers is disrupted by Tp0751-specific antiserum. Further, we identify the 67-kDa laminin receptor (LamR) as an endothelial receptor for Tp0751 using affinity chromatography, coimmunoprecipitation, and plate-based binding methodologies. Notably, LamR has been identified as a receptor for adhesion of other neurotropic invasive bacterial pathogens to brain endothelial cells, including Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae, suggesting the existence of a common mechanism for extravasation of invasive extracellular bacterial pathogens.IMPORTANCE Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subsp. pallidum. The continued incidence of syphilis demonstrates that screening and treatment strategies are not sufficient to curb this infectious disease, and there is currently no vaccine available. Herein we demonstrate that the T. pallidum adhesin Tp0751 interacts with endothelial cells that line the lumen of human blood vessels through the 67-kDa laminin receptor (LamR). Importantly, LamR is also a receptor for meningitis-causing neuroinvasive bacterial pathogens such as Neisseria meningitidis, Haemophilus influenzae, and Streptococcus pneumoniae Our findings enhance understanding of the Tp0751 adhesin and present the intriguing possibility that the molecular events of Tp0751-mediated treponemal dissemination may mimic the endothelial interaction strategies of other invasive pathogens.

Prevalence and protective factors of HIV and syphilis infection among men who have sex with men in Northwest China

BACKGROUND

Men who have sex with men (MSM) continue to be disproportionately impacted by human immunodeficiency virus (HIV) and syphilis in China. Little is known about HIV and syphilis infections among MSM in Xi'an, a developing city in Northwest China. A cross-sectional study with recruitment via snowball sampling was conducted to collect HIV and syphilis infection status and risk factors among MSM in Xi'an between April 2013 to December 2016. Among the 5000 participants, the mean age was 29.0 years (SD 7.7) and the prevalence of HIV, syphilis, and coinfection was 6.5%, 2.2%, and 0.4%, respectively. There was no significant change in HIV prevalence from 2013 to 2016, while the prevalence of syphilis and coinfection showed a downward trend. Multiple logistic regression analyses found that being over 25 years old (OR = 1.647), junior high school/middle school education and below (OR = 3.085), with a sexual role of passive or versatile (OR = 3.300; OR = 2.337), rush poppers use during the last 6 months (OR = 1.660) and syphilis infection (OR = 2.235) were more likely to acquire HIV infection, whereas used condoms in the last episode of anal sex (OR = 0.572) and tested HIV antibody previously (OR = 0.252) were protective factors for HIV infection. HIV prevalence among MSM in Xi'an was stable, whereas the prevalence of syphilis and coinfection showed a downward trend. Interventions to promote HIV and sexually transmitted disease testing and condom use should be strengthened, especially for MSM with low education.

What has changed HIV and syphilis infection among men who have sex with men (MSM) in Southwest China: a comparison of prevalence and behavioural characteristics (2013-2017)

Background

Chongqing reportedly has a large MSM population and a high STI prevalence in previous studies. However, most studies are attributed to independent cross-sectional studies, few studies have investigated trends in the prevalence of syphilis and HIV, as well as behavioural characteristics among MSM using serial surveillance surveys.

Methods

Data were collected in Chongqing through face-to-face questionnaire interview and laboratory testing in Chongqing. The respondents were recruited among MSM by snowball sampling from May 2013 to December 2017. The self-report questionnaire primarily included socio-demographics, HIV knowledge, and HIV-related behaviour characteristics over the year. Blood specimens were tested to diagnose HIV and syphilis infection by Chongqing CDC. Cochran-Armitage trend test and multivariate logistic regression were conducted to compare the changes in STI prevalence and independent behavioural factors among MSM.

Results

There were 6568 eligible participants (98.4%). The overall HIV prevalence was 20.5% among MSM in Chongqing, with a decrease from 23.0% in 2013 to 19.2% in 2017. The overall syphilis prevalence was 5.8%, with an increase from 3.2% in 2013 to 6.7% in 2017. The proportion of consistent condom use (CCU) during anal intercourse (46.3 to 57.7%, P<0.001),CCU with regular male partners(47.7 to 59.7%, P<0.001), CCU with casual male partners (51.5 to 62.3%, P<0.001) and drug use during anal intercourse (0.3 to 1.4%, P<0.05) were increasing. By contrast, a significant decrease was reported in the percentage of MSM with more than two regular male partners (66.0 to 21.4%, P<0.001) and more than two casual male partners (38.3 to 20.7%, P<0.001). A significant difference was observed in syphilis infection, testing for HIV antibodies and drug use during anal intercourse in the past years between the HIV-positive and HIV-negative respondents.

Conclusion

A decreasing trend of HIV prevalence was showed during among MSM from 2013 to 2017 in Chongqing. While gradual reduction of high-risk behaviors along with HIV prevalence supported development of STI counselling and testing, increasing syphilis infection and drug use during anal intercourse warrants further understanding.

As through a glass, darkly: the future of sexually transmissible infections among gay, bisexual and other men who have sex with men

The trajectory of sexually transmissible infection (STI) incidence among gay and other men who have sex with men (MSM) suggests that incidence will likely remain high in the near future. STIs were hyperendemic globally among MSM in the decades preceding the HIV epidemic. Significant changes among MSM as a response to the HIV epidemic, caused STI incidence to decline, reaching historical nadirs in the mid-1990s. With the advent of antiretroviral treatment (ART), HIV-related mortality and morbidity declined significantly in that decade. Concurrently, STI incidence resurged among MSM and increased in scope and geographic magnitude. By 2000, bacterial STIs were universally resurgent among MSM, reaching or exceeding pre-HIV levels. While the evidence base necessary for assessing the burden STIs among MSM, both across time and across regions, continues to be lacking, recent progress has been made in this respect. Current epidemiology indicates a continuing and increasing trajectory of STI incidence among MSM. Yet increased reported case incidence of gonorrhoea is likely confounded by additional screening and identification of an existing burden of infection. Conversely, more MSM may be diagnosed and treated in the context of HIV care or as part of routine management of pre-exposure prophylaxis (PrEP), potentially reducing transmission. Optimistically, uptake of human papillomavirus (HPV) vaccination may lead to a near-elimination of genital warts and reductions in HPV-related cancers. Moreover, structural changes are occurring with respect to sexual minorities in social and civic life that may offer new opportunities, as well as exacerbate existing challenges, for STI prevention among MSM.

Dual rapid test for HIV and syphilis: A laboratory evaluation of the diagnostic accuracy of the Standard Q HIV/Syphilis Combo Test

We evaluated the Standard Q HIV/Syphilis Combo Test (SD Biosensor, South Korea), a dual rapid test using stored sera (N = 400) in a laboratory setting in Lima, Peru. The sensitivity and specificity for HIV antibody detection was 100.0% (95% CI: 98.2-100.0%) and 99.5% (95% CI: 97.2-100.0%), respectively. For treponemal antibody detection the sensitivity and specificity was 97.5% (95%CI:94.3-99.2%) and 100.0% (95%CI:98.2-100.0%), respectively.

Leading by Example: Web-Based Sexual Health Influencers Among Men Who Have Sex With Men Have Higher HIV and Syphilis Testing Rates in China

Background

The spread of healthy behaviors through social networks may be accelerated by influential individuals. Previous studies have used lay health influencers to prevent sexually transmitted infections (STIs) among internet-using men who have sex with men (MSM). However, there is a lack of understanding of the characteristics of this key subset of MSM.

Objective

This study aimed to examine sociodemographic characteristics, HIV and syphilis testing, and sexual behaviors of Web-based MSM sexual health influencers (SHIs) in China, defined as individuals with relatively stronger influence on spreading HIV and STI information online.

Methods

A Web-based survey of MSM was conducted in August 2017 as a final follow-up of a randomized controlled trial promoting HIV testing in 8 Chinese cities. Men were recruited through a gay social networking mobile phone app and were included if they were born biologically male, aged 16 years and above, ever had sex with another man, and HIV negative or with unknown HIV status. Information regarding sociodemographic characteristics, sexual behaviors, and HIV and syphilis testing was obtained. We assessed men’s Web-based sexual health influence using a standardized 6-item opinion leadership scale focused on HIV and STI information. Influencers were defined as those whose mean score ranked within the top 13% (a higher score means greater influence). We used multivariable linear and logistic regression models to measure Web-based sexual health influence’s association with HIV and syphilis testing, controlling for intervention trial effects, age, education, income, and marital status.

Results

Overall, 1031 men completed the survey. Most men were younger than 30 years (819/1031, 79.43%) and had at least college education (667/1031, 64.69%). Influencers were more likely to get tested for HIV (73/132, 55.3% vs 337/899, 37.5%; P<.001) and syphilis (35/132, 26.5% vs 137/899, 15.2%; P=.001) in the last 3 months compared with noninfluencers. There were no significant differences in condomless sex with male partners (26/132, 19.7% vs 203/899, 22.6%; P=.46), mean number of male sex partners (1.32 vs 1.11; P=.16) in the last 3 months, and mainly meeting male sex partners online in the last 12 months (97/132, 73.5% vs 669/899, 74.4%; P=.82) between influencers and noninfluencers. Regression analyses showed that influencers had higher odds of HIV testing (adjusted odds ratio, AOR 2.16, 95% CI 1.48-3.17) and syphilis testing (AOR 1.99, 95% CI 1.28-3.10) in the last 3 months.

Conclusions

We identified Web-based SHIs who might be more likely to help promote healthy HIV and syphilis testing behaviors through MSM populations. Leveraging existing influencers may help improve HIV and syphilis testing among their networks.

An Update on the Global Epidemiology of Syphilis

PURPOSE OF REVIEW

Syphilis continues to cause morbidity and mortality worldwide. While syphilis infection is easily identifiable and treatable, rates of syphilis infection continue to increase among select populations in high-income countries and remain at endemic levels in low- and middle-income counties.

RECENT FINDINGS

World Health Organization recommended strategies have led to the dual elimination of mother-to-child transmission of syphilis and HIV in several countries, however outbreaks among select populations need to be adequately addressed.

SUMMARY

Continued vigilance and investment is needed to address syphilis worldwide. The epidemiology of syphilis differs in high-income and low- and middle-income counties.

A defined syphilis vaccine candidate inhibits dissemination of Treponema pallidum subspecies pallidum

Syphilis is a prominent disease in low- and middle-income countries, and a re-emerging public health threat in high-income countries. Syphilis elimination will require development of an effective vaccine that has thus far remained elusive. Here we assess the vaccine potential of Tp0751, a vascular adhesin from the causative agent of syphilis, Treponema pallidum subsp. pallidum. Tp0751-immunized animals exhibit a significantly reduced bacterial organ burden upon T. pallidum challenge compared with unimmunized animals. Introduction of lymph nodes from Tp0751-immunized, T. pallidum-challenged animals to naive animals fails to induce infection, confirming sterile protection. These findings provide evidence that Tp0751 is a promising syphilis vaccine candidate.

There are no vaccines for the prevention of syphilis, a disease caused by the bacterium Treponema pallidum subsp. pallidum. Here, the authors use an animal model of infection to show that immunization with the Tp0751 bacterial protein inhibits the pathogen's spread within the body.

Increased incidence of syphilis in men who have sex with men and risk management strategies, Germany, 2015

In Germany, the number of reported syphilis cases increased between 11% and 22% per year between 2010 and 2014. We analysed syphilis surveillance data and data of four behavioural surveys on men who have sex with men (MSM) in Germany (2003, 2007, 2010, 2013) to assess if this rise is ongoing and to find possible explanations for it. Syphilis notifications increased in 2015 by 19% to a total of 6,834. This was mainly due to increasing notifications in MSM of all age groups in larger German cities. Data from the behavioural surveys on MSM in Germany showed a simultaneous increase of selective condom use as HIV-status-bases risk management strategy and the number of syphilis cases. MSM diagnosed with HIV reported condomless anal intercourse with non-steady partners more frequent than MSM not diagnosed with HIV or untested for HIV, but the latter also reported higher frequencies of this behaviour in the more recent surveys. Transmission in HIV-positive MSM probably plays an important, but not exclusive role, for the syphilis dynamics in Germany. A risk adapted routine screening for sexually active MSM and potentially innovative approaches to increase early screening and treatment of syphilis such as internet counselling, home sampling, home testing and broadening venue-based (rapid) testing, should be critically evaluated to effectively reduce syphilis infections.