Syphilis predicts HIV incidence among men and transgender women who have sex with men in a preexposure prophylaxis trial

The development of an online risk calculator for the prediction of future syphilis among a high-risk cohort of men who have sex with men and transgender women in Lima, Peru

Background Syphilis incidence worldwide has rebounded since 2000, particularly among men who have sex with men (MSM). A predictive model for syphilis infection may inform prevention counselling and use of chemoprophylaxis.

METHODS

Data from a longitudinal cohort study of MSM and transgender women meeting high-risk criteria for syphilis who were followed quarterly for 2 years were analysed. Incidence was defined as a four-fold increase in rapid plasma reagin (RPR) titres or new RPR reactivity if two prior titres were non-reactive. Generalised estimating equations were used to calculate rate ratios (RR) and develop a predictive model for 70% of the dataset, which was then validated in the remaining 30%. An online risk calculator for the prediction of future syphilis was also developed.

RESULTS

Among 361 participants, 22.0% were transgender women and 34.6% were HIV-infected at baseline. Syphilis incidence was 19.9 cases per 100-person years (95% confidence interval (CI) 16.3-24.3). HIV infection (RR 2.22; 95% CI 1.54-3.21) and history of syphilis infection (RR 2.23; 95% 1.62-3.64) were significantly associated with incident infection. The final predictive model for syphilis incidence in the next 3 months included HIV infection, history of syphilis, number of male sex partners and sex role for anal sex in the past 3 months, and had an area under the curve of 69%. The online syphilis risk calculator based on those results is available at: www.syphrisk.net.

CONCLUSIONS

Using data from a longitudinal cohort study among a population at high risk for syphilis infection in Peru, we developed a predictive model and online risk calculator for future syphilis infection. The predictive model for future syphilis developed in this study has a moderate predictive accuracy and may serve as the foundation for future studies.

Subsequent HIV Diagnosis Risk After Syphilis in a Southern Black Population

BACKGROUND

Southern non-Hispanic black persons are disproportionately represented in the HIV epidemic. Those previously diagnosed as having syphilis are at significant risk to become HIV infected within 36 months. Effective prevention strategies such as preexposure prophylaxis should be offered to those at highest risk to maximize prevention efforts.

METHODS

HIV-negative persons diagnosed as having primary or secondary (P&S) syphilis during 1998-2014 were matched with incident HIV cases diagnosed during 1998-2016 in Shelby County Tennessee. Person-year HIV incidence rate, Kaplan-Meier survival estimates, and Cox proportional regression model analyses were performed to explore predicting risk factors and quantifying risk factors associated with HIV-free survival time frames.

RESULTS

Among 2032 HIV-negative non-Hispanic black Shelby County residents diagnosed as having P&S syphilis, 139 (6.8%) were subsequently diagnosed as having HIV infection. Men who have sex with men (MSM) experienced the highest incidence of HIV diagnosis rate (4.98 per 100 person-years, 95% confidence interval, 4.76-5.2). Being male, MSM, younger than 30 years, or coinfected with gonorrhea increased risk of HIV acquisition 2.32, 11.80, 1.67, and 2.44 times, respectively, compared with being female, heterosexual men, 30+ years old, or not infected with other sexually transmitted infections.

CONCLUSIONS

Among our population diagnosed as having P&S syphilis, 1 in 6 MSM and 1 in 16 persons coinfected with gonorrhea were subsequently diagnosed as having HIV during 36 months of follow-up. These findings have implications for HIV screening and recruitment as priority preexposure prophylaxis candidates.

Sexually Transmitted Infections Detected During and After Incarceration Among People with Human Immunodeficiency Virus: Prevalence and Implications for Screening and Prevention

BACKGROUND

Incarceration and human immunodeficiency virus (HIV) are associated with sexually transmitted infections (STIs); however, little is known about STI prevalence among people living with HIV (PLWH) during and after incarceration.

METHODS

Electronic medical records from the Dallas County Jail and community HIV clinics were reviewed to determine the frequency and results of testing for gonorrhea, chlamydia, syphilis, and hepatitis B virus (HBV) among PLWH incarcerated in Dallas County Jail between 2010 and 2013. HIV viral loads (VL) and evidence of STI symptoms and treatment were also collected.

RESULTS

During 2473 incarcerations, 6 (3%) of 190 tests were positive for gonorrhea, 7 (4%) of 190 for chlamydia, 231 (21%) of 1082 for syphilis, of which 53 (23%) were new diagnoses, and 48 (5%) of 1005 for HBV surface antigen. Among 1631 releases to the community, 808 followed up in community clinics, where 21 (4%) 553 tests were positive for gonorrhea, 23 (4%) of 555 for chlamydia, 150 (19%) of 808 for syphilis, of which 31 (21%) were new diagnoses, and 24 (6%) of 421 for HBV surface antigen. The majority of new STI cases, 51 (80%) of 64 in jail and 43 (77%)of 56 in the community, had a concurrent detectable (>200 copies/mL) HIV VL.

CONCLUSIONS

Testing for gonorrhea and chlamydia was low, particularly in jail, which was attributed to testing protocols. High proportions of PLWH tested positive for syphilis and HBV infection in both settings. The majority of patients with active STIs had a detectable HIV VL. Routine, opt-out screening for STIs for PLWH during and after incarceration has the potential to identify a high proportion of STIs and improve secondary HIV prevention.

Sexual network characteristics of men who have sex with men with syphilis and/or gonorrhoea/chlamydia in Lima, Peru: network patterns as roadmaps for STI prevention interventions

OBJECTIVE

While men who have sex with men (MSM) are disproportionately affected by Peru's overlapping HIV and STI epidemics, there are few data on how partnership-level and network-level factors affect STI transmission in Peru. We explored partnership-level and network-level factors associated with gonorrhoea/chlamydia (Neisseria gonorrhoeae and/or Chlamydia trachomatis (NG/CT)) and/or syphilis infection among MSM in Peru.

METHODS

We present the results of a cross-sectional secondary analysis of MSM (n=898) tested for syphilis and NG/CT infection as part of the screening process for two STI control trials in Lima, Peru. Participants completed questionnaires on demographics, sexual identity and role, characteristics of their three most recent sexual partners (partner sexual orientation, gender, role, partnership type, partner-specific sexual acts) and 30-day sexual network characteristics (number of sexual partners, partnership types, frequency of anal/vaginal intercourse). Participants were tested for syphilis and urethral, rectal and oropharyngeal NG/CT. Differences in network characteristics were analysed with χ2 and Kruskal-Wallis tests.

RESULTS

Approximately 38.9% of participants had a new STI diagnosis (syphilis (rapid plasma reagin ≥16): 10.6%; NG/CT: 22.9%; syphilis-NG/CT coinfection: 5.4%). Condomless anal intercourse (CAI) was not significantly associated with an STI diagnosis. Gay-identified participants with exclusively homosexual networks had a higher prevalence of STIs (47.4%) than gay-identified MSM with only heterosexual/bisexual partners (34.6%, p=0.04), despite reporting fewer sexual partners (any partners: 2, 1-4 vs 3, 2-6; p=0.001; casual partners: 1, 0-3 vs 2, 1-4; p=0.001) and more stable partnerships (1, 0-1 vs 0, 0-1; p=0.003) in the last month.

CONCLUSIONS

Network size and the number of casual sexual partners were associated with NG/CT infection among MSM in Peru. Despite reporting fewer sexual risk behaviours (smaller network size, more stable partnerships, less CAI), MSM with homosexual-only sexual networks had a higher prevalence of NG/CT and syphilis. These findings suggest network composition among MSM in Peru plays an important role in the risk for STI acquisition.

A Nonhuman Primate Model for Rectally Transmitted Syphilis

Among men who have sex with men (MSM), those with a diagnosis of syphilis or other rectal sexually transmitted infections (STIs) are at a higher risk for human immunodeficiency virus acquisition, which is concerning given the large increase in recently reported syphilis cases in the United States. We have developed the first nonhuman primate model for rectally transmitted syphilis by exposing simian/human immunodeficiency virus-infected and naive rhesus macaques to Treponema pallidum in the rectum. All animals showed mucosal lesions, systemic dissemination, and seroconversion (treponemal antibodies). This model would be valuable for studying the manifestations of and interventions for T. pallidum infection, with and without human immunodeficiency virus coinfection.

HIV Initial Assessment and Routine Follow-up: What Tests to Order and Why

Laboratory tests are an important tool in the care of patients with human immunodeficiency virus. An organized approach to laboratory ordering helps clinicians to understand the utility of each test, ensure a comprehensive evaluation, and decrease use of unnecessary tests. Tests are organized around the following goals of care: confirm the diagnosis, assess for immune suppression, guide antiretroviral therapy, screen for coinfections and latent infections, monitor response to therapy, and provide preventative care. This article reviews appropriate testing for patients with human immunodeficiency virus to accomplish these goals with a focus on how each test is useful in clinical practice.

Seroreactivity and prevalence of syphilis in donors at a blood bank in Barranquilla, Colombia

Introduction: Syphilis is a public health concern given its high impact on morbidity and mortality. Objective: We aimed to determine the association of syphilis seroreactivity and seroprevalence with sociodemographic variables of donors at a blood bank in the district of Barranquilla, Colombia, during 2015 and 2016. Materials and methods: We conducted a descriptive cross-sectional study based on the results of the treponemal and nontreponemal tests and the sociodemographic variables of the study population. We performed a univariate analysis to determine the absolute and relative frequencies for each categorical variable. We determined the seroreactivity against Treponema pallidum and the prevalence of active syphilis infection, and we used Pearson’s chi-square test to evaluate the differences between the proportions. Results: We found a seroreactivity of 1.86% in individuals with previous T. pallidum infection, and a prevalence of 0.93% in those with active T. pallidum infection. These values were higher in adult men and older adults, widowers, the unemployed, and people living in municipalities of the Department of Atlántico other than Barranquilla and its metropolitan area. The incidence of syphilis infection showed a significant association with sex and occupation. Conclusion: In comparison to the national average, syphilis seroreactivity was high among blood donors. There was an association between syphilis infection incidence and sociodemographic variables such as sex and occupation.

Sexually acquired syphilis: Laboratory diagnosis, management, and prevention

The methods used for the laboratory diagnosis of syphilis include direct detection of Treponema pallidum subspecies pallidum and serologic testing. Serologic testing relies on both nontreponemal and treponemal tests. In newly developed reverse-sequence screening algorithms, treponemal tests are performed before nontreponemal tests. The management of syphilis requires appropriate staging, treatment, and follow-up of patients along with the prompt reporting of infections to public health authorities to assist with prevention and control efforts. Benzathine penicillin G remains the treatment of choice for all stages of syphilis. Screening of populations at higher risk for syphilis is recommended by the US Centers for Disease Control and Prevention, the US Preventive Services Task Force, and the World Health Organization. The second article in this continuing medical education series reviews the testing for and the management of sexually acquired syphilis.

Immunological Changes in Monocyte Subsets and Their Association With Foxp3+ Regulatory T Cells in HIV-1-Infected Individuals With Syphilis: A Brief Research Report

The incidence of syphilis has increased dramatically in men who have sex with men (MSM), especially those with HIV-1 infection. Treponema pallidum and HIV-1 are bidirectionally synergistic, accelerating disease progression reciprocally in co-infected individuals. We have shown that monocytes have different effects on T helper cells at different stages of HIV-1 infection. However, the immunological changes in the three monocyte subsets and in regulatory T cells (Tregs), and the associations between these cell types during syphilis infection among HIV-1-infected MSM remain unclear. Herein, we used cell staining methods to explore changes in monocyte subsets and Tregs and any associations between these cells. We found that the frequency of classical monocytes was higher in the rapid plasma reagin (RPR⁺) group than in the healthy controls (HCs) and the chronic HIV-1 infection (CHI) plus RPR⁺ (CHI&RPR⁺) group. The frequencies of Foxp3⁺CD25⁺CD45RA⁺ and Foxp3⁺Helios⁺CD45RA⁺ Tregs were significantly higher in the RPR⁺, CHI, and CHI&RPR⁺ groups than in HCs, whereas the frequency of CD45RA⁺ Tregs was lower in the CHI&RPR⁺ group than in CHI group. The frequencies of Foxp3⁺CD25⁺CD45RO⁺ and Foxp3⁺Helios⁺CD45RO⁺ Tregs were lower in the RPR⁺, CHI, and CHI&RPR⁺ groups than in HCs. The frequency of intermediate monocytes was inversely correlated with the frequency of CD45RA⁺ Tregs and positively correlated with the frequency of CD45RO⁺ Tregs. These results demonstrate for the first time that intermediate monocytes control the differentiation of Treg subsets in Treponema pallidum/HIV-1 co-infections. These findings provide new insights into an immunological mechanism involving monocytes/Tregs in HIV-infected individuals with syphilis.

Syphilis

Syphilis is an infectious disease caused by the spirochaete Treponema pallidum subsp. pallidum which is transmitted by sexual contact or vertical transmission during pregnancy. The incidence of syphilis has increased in the last years, mainly among men who have sex with men. Without treatment, the disease develops into different clinical stages, being able to present cardiovascular or irreversible neurological complications after a number of years. The disease is classified as early syphilis - primary, secondary and early latent syphilis (less than 12 months) - which is contagious, and as late syphilis - late latent and tertiary syphilis- which is rarely contagious. Diagnosis and management are often a challenge because of its diversity of manifestations and the difficulty of interpretation of serological tests. The treatment of syphilis is based on penicillin or doxycycline in allergic patients. Treatment failure because of resistance has been described with azithromycin. The follow up with a serological test is recommended in all patients with syphilis in order to ascertain cure after the treatment and to diagnose possible reinfections.

Why we need pre-exposure prophylaxis: incident HIV and syphilis among men, and transgender women, who have sex with men, Bangkok, Thailand, 2005-2015

We describe incident human immunodeficiency virus (HIV) and syphilis trends in men who have sex with men (MSM) and transgender women (TGW) presenting for HIV voluntary counseling and testing (VCT) services and sexually transmitted infection (STI) management at the Silom Community Clinic, Bangkok, Thailand. Clients underwent rapid HIV testing and syphilis rapid plasma reagin (RPR) testing. For incidence analysis, we included clients with >1 follow-up visit. Initial negative HIV with subsequent positive HIV defined incident HIV infection; incident syphilis infection was defined as negative RPR followed by positive RPR (titer ≥1:8) and confirmatory anti- Treponema pallidum antibodies. Calculation of incidence using Poisson regression assumed a uniform probability distribution throughout the seroconversion interval. From 15 September 2005 to 31 December 2015, we tested 10,158 clients for HIV and 10,324 for syphilis. Overall, 7109 clients tested HIV-seronegative and contributed 7157 person-years (PY). Three-hundred forty-seven incident HIV infections resulted in an incidence rate of 4.8 per 100 PY (95% confidence interval [CI] 4.4-5.4). We found an inverted U-shape trend of HIV incidence over time with a peak of 6.4 per 100 PY in quarter 2/2011 ( p < 0.01) (Poisson with RCS function, p = 0.001). Overall, 8713 clients tested seronegative for syphilis and contributed 8623 PY. The incidence of syphilis infection was 4.4 per 100 PY (95% CI 3.9-4.8). Despite an apparent decline in HIV incidence among MSM and TGW attending VCT services, syphilis incidence rose and remained high. Evaluating temporal trends of HIV and syphilis incidence provides an opportunity to evaluate epidemic trajectories and target limited program funding. We recommend focused HIV and STI prevention interventions for MSM in Bangkok.

Behavioral characteristics and their association with syphilis seroprevalence among a cohort of young Black men who have sex with men

The objective of this study was to describe the sociodemographic characteristics and behavioral factors that are associated with syphilis seroprevalence in a cohort of young Black men who have sex with men (YBMSM) in Chicago, USA (n = 606). The weighted syphilis seroprevalence in the study population was 29.2% (95% CI 23.9, 35.1). A bivariate probit multiple regression model was used to estimate the outcomes. Characteristics that were positively associated with syphilis seropositivity included being age 19-20, 21-24, and at least age 25 compared to the reference group (age 16-18 years old) (0.72 [95% CI 0.18, 1.25], 1.40 [95% CI 0.68, 2.13], and 1.34 [95% CI 0.75,1.94], respectively), using social media to meet sexual partners (0.33 [95% CI 0.05, 0.61]), using condoms more often (0.39 [95% CI 0.02, 0.76]), and a history of criminal justice involvement (0.25 [95% CI 0.06, 0.44]). Our study results suggest that among YBMSM in Chicago, interventions promoting condom use may be less effective for syphilis prevention compared to HIV prevention in this population. The contribution of nonpenetrative sex to syphilis prevalence requires additional research as does how best to implement routine syphilis screening and treatment for YBMSM in the context of ongoing syphilis transmission.

Incidence of sexually transmitted infections in men who have sex with men and who are at substantial risk of HIV infection - A meta-analysis of data from trials and observational studies of HIV pre-exposure prophylaxis

BACKGROUND

Men who have sex with men (MSM) and who engage in condomless anal intercourse with casual partners are at high risk of acquiring sexually transmitted infections (STIs), but reliable epidemiological data are scarce. Studies on HIV pre-exposure prophylaxis (PrEP) enrol MSM who indicate that they engage in behaviour that puts them at high risk of acquiring HIV. Because they also screen for STIs at regular intervals, these studies may serve as a valuable source to estimate incidence rates of STIs in this subpopulation of MSM.

METHODS

We systematically searched for trials and observational studies of PrEP in MSM that reported data on the incidence of STIs during the study period. Incidence rates were calculated as events per 100 person-years (py) with 95% confidence intervals (CI). Data from individual studies were pooled building subgroups along study types and geography. We performed sensitivity analyses, including data only from studies that met pre-defined quality criteria.

RESULTS

Twenty-four publications on 20 studies were included. The majority of studies reported that sexual behaviour and/or STI incidence remained stable or decreased during the study period. For syphilis, incidence rates ranged from 1.8/100py to 14.9/100py, the pooled estimate was 9.1/100py (95%-CI: 7.7-10.9). Incidence rates for gonorrhoea and chlamydia of any site ranged from 13.3/100py to 43.0/100py and 15.1/100py to 48.5/100py, respectively. Considering only studies that met the criteria for sensitivity analysis yielded pooled estimates of 39.6/100py (95%-CI: 32.9-47.6) and 41.8/100py (95%-CI: 33.9-51.5), respectively. The overall estimate for hepatitis C incidence was 1.3/100py (95%-CI: 1.0-1.8).

CONCLUSIONS

Despite partly heterogeneous results, the data depict high incidence rates of STIs among MSM who engage in higher-risk sexual behaviours such as condomless sex with casual partners. This subpopulation of MSM requires access to STI screening at close intervals. By offering access to structures that provide regular STI monitoring and prompt treatment, PrEP may not only decrease HIV incidence but also have beneficial effects in decreasing the burden of STIs.

Risk Factors and Incidence of Syphilis in Human Immunodeficiency Virus (HIV)-Infected Persons: The HIV Outpatient Study, 1999-2015

Background

Since 2000, the incidence of syphilis has been increasing, especially among gay, bisexual, and other men who have sex with men (MSM) in the United States. We assessed temporal trends and associated risk factors for newly diagnosed syphilis infections among human immunodeficiency virus (HIV)-infected patients during a 16-year period.

Methods

We analyzed data from the HIV Outpatient Study (HOPS) cohort participants at 10 US HIV clinics during 1999-2015. New syphilis cases were defined based on laboratory parameters and clinical diagnoses. We performed Cox proportional hazards regression analyses of sociodemographic, clinical, and behavioral risk factors for new syphilis infections.

Results

We studied 6888 HIV-infected participants; 641 had 1 or more new syphilis diagnoses during a median follow-up of 5.2 years. Most participants were male (78%), aged 31-50 years, and 57% were MSM. The overall incidence was 1.8 (95% confidence interval [CI], 1.6-1.9) per 100 person-years (PY) and it increased from 0.4 (95% CI, .2-.8) to 2.2 (95% CI, 1.4-3.5) per 100 PY during 1999-2015. In multivariable analyses adjusting for calendar year, risk factors for syphilis included age 18-30 years (hazard ratio [HR], 1.3 [95% CI, 1.1-1.6]) vs 31-40 years, being MSM (HR, 3.1 [95% CI, 2.4-4.1]) vs heterosexual male, and being non-Hispanic black (HR, 1.6 [95% CI, 1.4-1.9]) vs non-Hispanic white.

Conclusions

The increases in the syphilis incidence rate through 2015 reflect ongoing sexual risk and highlight the need for enhanced prevention interventions among HIV-infected patients in care.

The relationship between anogenital HPV types and incident HIV infection among men who have sex with men and transgender women in Lima, Peru: Findings from a prospective cohort study

Although it is known that individuals living with HIV have a higher HPV prevalence, the impact of individual HPV types on HIV acquisition is less clear. In this prospective cohort study we investigated the relationship between HPV types and incident HIV infection among men who have sex with men (MSM) and transgender women (TW) in Lima, Peru. Six hundred HIV-negative Peruvian MSM and TW participated in a 2-year study with biannual visits. At baseline, participants completed a computerized, self-administered questionnaire on sexual behavior and HPV knowledge and underwent a physical exam including anogenital swabs for HPV DNA (37 genotypes via linear array testing) and HIV testing; follow-up visits included the questionnaire and HIV testing. Participant mean age was 25 years (range = 18-40), with 48.9% self-identifying as gay and 86.5% reporting having sex exclusively with men. At baseline, 530 participants had HPV DNA present (61.1% with high-risk HPV, 84.9% with low-risk HPV). Among 571 participants who returned for any study visit, 73 (12.8%) became infected with HIV during the 2-year follow-up (6% HIV incidence). Compared to those without HIV, more participants with HIV had any HPV type present (97.3% vs. 87.6%, respectively, p = .01), more than one HPV type (79.5% vs. 58.2%, p < .01), or high-risk HPV (72.6% vs. 51.4%, p < .01). Some participants lost to follow-up could have been HIV-positive, which would have affected the relationship of HPV and HIV infection. Our prospective study showed that participants with any HPV type, more than one HPV type, or high-risk HPV were more likely to test positive for HIV. Although most studies have shown HPV-HIV coinfection, our findings illustrate the strong relationship between individual HPV types and HIV infection. This further illustrates the potential utility of HPV vaccine for MSM and TW, not only for HPV prevention but also possibly for HIV prevention.

Latent Classes of Sexual Risk Among Black Men Who Have Sex with Men and Women

Black men who have sex with men and women (BMSMW) are at high risk for HIV and other sexually transmitted infections (STIs). Despite knowing that HIV/STI risk varies by sexual positioning practices, limited data have characterized the risk profiles of BSMW. This study utilized latent class analysis (LCA) to explore BMSMW's sexual risk profiles regarding condomless sexual positioning practices. Participants were BMSMW in intervention studies in Los Angeles, Chicago, and Philadelphia. LCA was used to characterize their sexual risk profiles. Age, study location, HIV status, social support, and internalized homophobia were used as covariates in a multinomial regression model predicting the likelihood of class membership. Among the 546 participants, three latent classes of risk were identified: Seropositive Serosorters, Seronegative/unknown Serosorters, and Main Partners Only. All groups had the greatest probabilities of condomless sex with main partners. Seropositive Serosorters had the highest probabilities of condomless sex with HIV-positive partners. Seronegative/unknown Serosorters had the highest probabilities of condomless sex with HIV-negative or unknown status partners. HIV-positive BMSMW had 87% lower odds of being classified as Seronegative/unknown Serosorters than Seropositive Serosorters than HIV-negative/unknown status BMSMW (AOR = 0.13, 95% CI 0.06, 0.28). HIV-positive BMSMW had 71% lower odds of being classified as Main Partners Only than Seropositive Serosorters than HIV-negative/unknown status BMSMW (AOR = 0.29, 95% CI 0.16, 0.51). Findings highlight opportunities for clinicians to promote condom use and risk reduction among BMSMW with differing sexual risk profiles. Increased understanding of sexual positioning practices among BMSMW might help address HIV/STIs among this group.

Gay Circuit Parties in Barcelona and Their Impact on Gonorrhea Incidence

This study explored the role of circuit parties on the incidence of gonorrhea among men who have sex with men (MSM) in Barcelona (Spain). Specifically, it aimed to detect cyclic peaks in the number of reported diagnoses of gonorrhea after gay circuit parties. We analyzed monthly cases of gonorrhea reported from January 2007 through December 2016 after the main annual gay circuit parties in Barcelona. We used the integer autoregressive model for time series with discrete values. The performance of the model was tested in heterosexual men and women, in whom the circuit parties could be expected to have no impact. A sensitivity analysis was conducted, changing post-event diagnosis windows to 1 week later/1 week before. In the study period, a total of 4182 of gonorrhea cases were detected, of which 74.8% (n = 2181) occurred in men who identified themselves as MSM. The average annual increase in gonorrhea cases reported among MSM was 32.57%. In an independent analysis of each gay circuit party, cases increased significantly in two of them. The results were also similar for same-sex practices among men only. On controlling for the increasing trend over the study period and the seasonal effect, an average of 1.16 gonorrhea cases in MSM (95% CI: 0.68, 1.64) were attributable to the celebration of one of the gay circuit parties considered. During the expected outbreak, an average of 13 gonorrhea cases were detected and between 5 and 13% were attributable to one of the circuit parties. In view of these findings, participants should consider seeking advice from their healthcare provider and practice safer sex using condoms to prevent sexually transmitted infections. Local public health services should be reinforced to ensure care for participants during and after gay circuit parties. More research is needed to design and implement preventive programs.

Quality of care and HIV service utilization among key populations in Zambia: a qualitative comparative analysis among female sex workers, men who have sex with men and people who use drugs

HIV epidemic control requires improving access and uptake of HIV services by key populations (KPs). In Zambia, the behaviors of female sex workers (FSWs), men who have sex with men (MSM), and people of who use drugs (PWUD) are criminalized, and little information exists about their HIV/STI service use. Using a quality of care (QOC) framework, we compared barriers to and opportunities for HIV/STI service access and uptake among the three KPs. We conducted in-depth interviews and focus group discussions with 314 KP members between July 2013 and September 2015 in eight districts. Poorer QOC was received at public health facilities compared to private, NGOs and traditional healers. Stigma and discrimination, confidentiality, and legal prosecution were barriers to service use and more salient among MSM than FSWs and PWUD. Invasive facility policies were barriers and more prominent among FSWs than MSM and PWUD. Service unavailability was of equally high salience among MSM and PWUD than FSWs. Comfort in the clinic and perceived treatment effectiveness were facilitators for all three KPs. The health care experiences of KPs are not monolithic; HIV/STI service improvement strategies should address the concerns and be tailored to the needs of each key population.

Old Pathogen, New Challenges: A Narrative Review of the Multilevel Drivers of Syphilis Increasing in American Men Who Have Sex With Men

Since the turn of the current century, syphilis incidence and prevalence have been increasing more rapidly among men who have sex with men (MSM) than any other US subpopulation, exceeding their previously high rates in the 1970s and 1980s, before the AIDS epidemic. The reasons for these trends are multifactorial and complex, involving individual behavioral, sociocultural, structural, and biological factors, which will be reviewed in this article. Men who have sex with men tend to have more sexual partners than heterosexuals, and engage in practices (e.g., anal sex) that are highly efficient for syphilis transmission and nondetection of primary chancres. In the era of highly active antiretroviral therapy rendering adherent patients noninfectious and the use of preexposure prophylaxis, there is substantially less concern about HIV transmission and acquisition among MSM, resulting in higher levels of condomless sex. The increased concentration of syphilis among black MSM is partially related to assortative mixing, that is, black MSM being more likely to have other black sex partners, as well as decreased access to preventive services and treatment due to economic marginalization, Societal rejection and discrimination may also potentiate factors that may increase sexual risks resulting in syphilis, for example, depression and substance use. The anticipation of experiencing homophobic discrimination in health care settings may lead many sexually active MSM to delay needed screening and treatment, thus being infectious to partners for longer periods than other populations. To effectively control the syphilis epidemic among MSM, scaling up a combination of programs, ranging from enhanced community education to training clinicians and health care systems to provide culturally competent care, will be necessary.

Social networks as drivers of syphilis and HIV infection among young men who have sex with men

OBJECTIVES

Syphilis and HIV epidemics overlap, yet little is known about combined network and behavioural factors that drive syphilis-HIV coinfection. Our study objective was to assess network contexts and sexual behaviours associated with syphilis-HIV co-infection and monoinfection among a particularly vulnerable subgroup: young Black men who have sex with men (YBMSM). To achieve this objective, we examined factors associated with coinfection by each subgroup as classified by syphilis-HIV infection status: (A) HIV monoinfected, (B) syphilis monoinfected and (C) neither syphilis infected nor HIV infected. In addition, we further identified the factors that are associated with HIV infection or syphilis monoinfection.

METHODS

Data were collected from a sample of 365 YBMSM, aged 16-29 years, recruited through respondent-driven sampling between 2014 and 2016, in two cities with large HIV epidemics: Houston, TX, and Chicago, IL. We conducted a series of multinomial logistic regression models to predict coinfection, HIV monoinfection and syphilis monoinfection as a function of network and sexual behavioural factors.

RESULTS

Coinfection was associated with having network members who are coinfected or HIV infected within one's social network. Syphilis monoinfection was associated with a higher number of social venues attended, and HIV monoinfection was associated with having more condomless top partners.

CONCLUSION

Public health interventions that address the diagnosis and treatment of syphilis infection and ensure that those with syphilis are being tested for HIV may be promising in limiting the synergy of syphilis-HIV infections in onward transmission. Advancing HIV and syphilis prevention efforts in high-prevalence networks may allow prioritisation of limited resources.

HIV, HCV, HBV, and syphilis among transgender women from Brazil: Assessing different methods to adjust infection rates of a hard-to-reach, sparse population

Different sampling strategies, analytic alternatives, and estimators have been proposed to better assess the characteristics of different hard-to-reach populations and their respective infection rates (as well as their sociodemographic characteristics, associated harms, and needs) in the context of studies based on respondent-driven sampling (RDS). Despite several methodological advances and hundreds of empirical studies implemented worldwide, some inchoate findings and methodological challenges remain. The in-depth assessment of the local structure of networks and the performance of the available estimators are particularly relevant when the target populations are sparse and highly stigmatized. In such populations, bottlenecks as well as other sources of biases (for instance, due to homophily and/or too sparse or fragmented groups of individuals) may be frequent, affecting the estimates.In the present study, data were derived from a cross-sectional, multicity RDS study, carried out in 12 Brazilian cities with transgender women (TGW). Overall, infection rates for HIV and syphilis were very high, with some variation between different cities. Notwithstanding, findings are of great concern, considering the fact that female TGW are not only very hard-to-reach but also face deeply-entrenched prejudice and have been out of the reach of most therapeutic and preventive programs and projects.We cross-compared findings adjusted using 2 estimators (the classic estimator usually known as estimator II, originally proposed by Volz and Heckathorn) and a brand new strategy to adjust data generated by RDS, partially based on Bayesian statistics, called for the sake of this paper, the RDS-B estimator. Adjusted prevalence was cross-compared with estimates generated by non-weighted analyses, using what has been called by us a naïve estimator or rough estimates.

Increased Syphilis Testing of Men Who Have Sex With Men: Greater Detection of Asymptomatic Early Syphilis and Relative Reduction in Secondary Syphilis

Background

Syphilis rates have increased markedly among men who have sex with men (MSM) internationally. We examined trends in syphilis testing and detection of early syphilis among MSM in Australia.

Methods

Serial cross-sectional analyses on syphilis testing and diagnoses among MSM attending a national sentinel network of 46 clinics in Australia between 2007 and 2014.

Results

359313 clinic visits were included. The proportion of MSM serologically tested for syphilis annually increased in HIV-negative (48% to 91%; Ptrend < .0001) and HIV-positive MSM (42% to 77%; Ptrend < .0001). The mean number of tests per man per year increased from 1.3 to 1.6 in HIV-negative MSM (Ptrend < .0001) and from 1.6 to 2.3 in HIV-positive MSM (Ptrend < .0001). 2799 and 1032 syphilis cases were detected in HIV-negative and HIV-positive MSM, respectively. Among HIV-negative MSM, the proportion of infections that were early latent increased from 27% to 44% (Ptrend < .0001), while the proportion that were secondary decreased from 24% to 19% (Ptrend = .030). Among HIV-positive MSM, early latent infections increased from 23% to 45% (Ptrend < .0001), while secondary infections decreased from 45% to 26% (Ptrend = .0003). Among HIV-positive MSM, decreasing secondary syphilis correlated with increasing testing coverage (r = -0.87; P = .005) or frequency (r = -0.93; P = .001).

Conclusions

Increases in syphilis screening were associated with increased detection of asymptomatic infectious syphilis and relative falls in secondary syphilis for both HIV-positive and HIV-negative MSM nationally, suggesting interruption of syphilis progression.

Impact of insurance coverage on HIV transmission potential among antiretroviral therapy-treated youth living with HIV

OBJECTIVE

To identify the prevalence of high HIV transmission potential in a cohort of youth living with HIV (YLWH), and determine the impact of insurance coverage on potential for HIV transmission.

DESIGN

Retrospective cohort study of antiretroviral therapy (ART)-treated YLWH at a US adolescent HIV clinic, 2002-2015.

METHODS

The primary exposure was presence or absence of insurance, defined as private, public or pharmacy-only coverage. The primary outcome was high HIV transmission potential, defined as time-concurrent incident bacterial sexually transmitted infections (STI) (gonorrhea, chlamydia or syphilis) and HIV RNA greater than 1500 copies/ml. Marginal structural models adjusting for baseline demographic covariates, prior history of STI and time-varying retention in care assessed the relationship between insurance status and HIV transmission potential.

RESULTS

Participants (n = 240) were followed for a median of 22 (IQR 8.1-49) months after ART initiation, and were predominately African-American men and transgender women who have sex with men, with a median age at HIV diagnosis of 19 years (IQR 17-21). We identified 37 (15%) participants with at least one episode of high HIV transmission potential. Insurance coverage was associated with a greater than 50% lower odds of high HIV transmission potential (aOR 0.46, 95% CI 0.26-0.84), and history of STI at or before entry to HIV care conferred more than three-fold higher odds of high transmission potential (aOR 3.21, 95% CI 1.55-6.63).

CONCLUSION

We found 15% of YLWH to have episodic high HIV transmission potential despite receiving ART. Insurance coverage, including pharmacy-only benefits, was protective against transmission risk, suggesting a pivotal role for universal ART coverage in treatment as prevention.

Sex, PrEP, and Stigma: Experiences with HIV Pre-exposure Prophylaxis Among New York City MSM Participating in the HPTN 067/ADAPT Study

The HPTN 067/Alternative Dosing to Augment Pre-Exposure Prophylaxis Pill Taking (ADAPT) study evaluated daily and non-daily dosing schedules for oral pre-exposure prophylaxis (PrEP) to prevent HIV. A qualitative sub-study including focus groups and in-depth interviews was conducted among men who have sex with men participating in New York City to understand their experience with PrEP and study dosing schedules. The 37 sub-study participants were 68% black, 11% white, and 8% Asian; 27% were of Hispanic/Latino ethnicity. Mean age was 34 years. Themes resulting from qualitative analysis include: PrEP is a significant advance for HIV prevention; non-daily dosing of PrEP is congruent with HIV risk; and pervasive stigma connected to HIV and risk behavior is a barrier to PrEP adherence, especially for non-daily dosing schedules. The findings underscore how PrEP intersects with other HIV prevention practices and highlight the need to understand and address multidimensional stigma related to PrEP use.

Maximizing the Benefits of HIV Preexposure Prophylaxis

Preexposure prophylaxis (PrEP) with tenofovir/emtricitabine (slash indicates coformulation) is highly effective in preventing new HIV infections. PrEP efficacy is strongly associated with adherence. In clinical trials, PrEP has been more effective in men who have sex with men and HIV-serodiscordant heterosexual couples than in women, likely reflecting pharmacokinetic differences between levels of tenofovir disoproxil fumarate in vaginal and rectal tissues, and poorer adherence in studies in women. Current guidelines recommend daily PrEP for men and women; however, PrEP taken at least 4 days per week for men may be as effective as daily PrEP, and women must take PrEP 6 to 7 days per week to maximize efficacy. Data are accumulating on the effectiveness of pericoital PrEP for men who have sex with men, but it is not yet recommended in the United States. PrEP is underprescribed for younger individuals, black individuals, and Hispanic and Latino individuals. This article summarizes a presentation by Susan P. Buchbinder, MD, at the IAS-USA continuing education program, Improving the Management of HIV Disease, held in Chicago, Illinois, in May 2017.

HIV Pre-exposure Prophylaxis (PrEP) Uptake and Retention Among Men Who Have Sex with Men in a Community-Based Sexual Health Clinic

In a community-based clinic serving men who have sex with men in San Francisco, California, this study characterized key steps of the pre-exposure prophylaxis (PrEP) cascade and identified correlates of retention in care. In total, 344 patients were evaluated for PrEP. Three-fourths (78%) of those who sought PrEP services initiated PrEP. The overall cumulative incidence of discontinuing PrEP at 13 months was 38%. Men with a sexually transmitted infection (STI) were 44% less likely to be retained (adjusted hazard ratio [aHR] 0.56, 95% confidence interval [0.33-0.95]). Comprehensive retention efforts for men with STIs are crucial to optimize the benefits of PrEP.

Sexually Transmitted Infections Among HIV-Infected Individuals in the District of Columbia and Estimated HIV Transmission Risk: Data From the DC Cohort

Background

Washington, DC, has one of the highest rates of HIV infection in the United States. Sexual intercourse is the leading mode of HIV transmission, and sexually transmitted infections (STIs) are a risk factor for HIV acquisition and transmission.

Methods

We evaluated the incidence and demographic factors associated with chlamydia, gonorrhea, and syphilis among HIV-infected persons enrolled at 13 DC Cohort sites from 2011 to 2015. Using Poisson regression, we assessed covariates of risk for incident STIs. We also examined HIV viral loads (VLs) at the time of STI diagnosis as a proxy for HIV transmission risk.

Results

Six point seven percent (451/6672) developed an incident STI during a median follow-up of 32.5 months (4% chlamydia, 3% gonorrhea, 2% syphilis); 30% of participants had 2 or more STI episodes. The incidence rate of any STIs was 3.8 cases per 100 person-years (95% confidence interval [CI], 3.5-4.1); age 18-34 years, 10.8 (95% CI, 9.7-12.0); transgender women, 9.9 (95% CI, 6.9-14.0); Hispanics, 9.2 (95% CI, 7.2-11.8); and men who have sex with men (MSM), 7.7 (95% CI, 7.1-8.4). Multivariate Poisson regression showed younger age, Hispanic ethnicity, MSM risk, and higher nadir CD4 counts to be strongly associated with STIs. Among those with an STI, 41.8% had a detectable VL within 1 month of STI diagnosis, and 14.6% had a VL ≥1500 copies/mL.

Conclusions

STIs are highly prevalent among HIV-infected persons receiving care in DC. HIV transmission risk is considerable at the time of STI diagnosis. Interventions toward risk reduction, antiretroviral therapy adherence, and HIV virologic suppression are critical at the time of STI evaluation.

Unevenness in Health at the Intersection of Gender and Sexuality: Sexual Minority Disparities in Alcohol and Drug Use Among Transwomen in the San Francisco Bay Area

Research on the health of transwomen is largely focused on heterosexual HIV risk. Little is known about the health of sexual minority transwomen. We conducted a secondary cross-sectional analysis of data from a HIV risk and resilience study of transwomen aged 16 to 24 years in the San Francisco Bay Area (N = 259). Prevalence and demographic characteristics of sexual minority transwomen was assessed and logistic regression models were used to examine the relationship between sexual minority status and alcohol and drug use. In logistic regression models, sexual minority transwomen had greater fold odds of heavy episodic drinking and illicit prescription drug use compared to their heterosexual counterparts, controlling for race/ethnicity, age, income, nativity, hormone status, and history of feminization procedures. These results suggest that sexual minority status may be an important social determinant of health among gender minorities. Populations of transwomen are heterogeneous; effective interventions must consider sexual minority status.

2016 United Kingdom national guideline on the sexual health care of men who have sex with men

This guideline is intended for use in UK Genitourinary medicine clinics and sexual health services but is likely to be of relevance in all sexual health settings, including general practice and Contraception and Sexual Health (CASH) services, where men who have sex with men (MSM) seek sexual health care or where addressing the sexual health needs of MSM may have public health benefits. For the purposes of this document, MSM includes all gay, bisexual and all other males who have sex with other males and both cis and trans men. This document does not provide guidance on the treatment of particular conditions where this is covered in other British Association for Sexual Health and HIV (BASHH) Guidelines but outlines best practice in multiple aspects of the sexual health care of MSM. Where prevention of sexually transmitted infections including HIV can be addressed as an integral part of clinical care, this is consistent with the concept of combination prevention and is included. The document is designed primarily to provide guidance on the direct clinical care of MSM but also makes reference to the design and delivery of services with the aim of supporting clinicians and commissioners in providing effective services. Methodology This document was produced in accordance with the guidance set out in the BASHH CEG's document 'Framework for guideline development and assessment' published in 2010 at http://www.bashh.org/guidelines and with reference to the Agree II instrument. Following the production of the updated framework in April 2015, the GRADE system for assessing evidence was adopted and the draft recommendations were regraded. Search strategy (see also Appendix 1) Ovid Medline 1946 to December 2014, Medline daily update, Embase 1974 to December 2014, Pubmed NeLH Guidelines Database, Cochrane library from 2000 to December 2014. Search language English only. The search for Section 3 was conducted on PubMed to December 2014. Priority was given to peer-reviewed papers published in scientific journals, although for many issues evidence includes conference abstracts listed on the Embase database. In addition, for 'Identification of problematic recreational drug and alcohol use' section and 'Sexual problems and dysfunctions in MSM' section, searches included PsycINFO. Methods Article titles and abstracts were reviewed and if relevant the full text article was obtained. Priority was given to randomised controlled trial and systematic review evidence, and recommendations made and graded on the basis of best available evidence. Piloting and feedback The first draft of the guideline was circulated to the writing group and to a small group of relevant experts, third sector partners and patient representatives who were invited to comment on the whole document and specifically on particular sections. The revised draft was reviewed by the CEG and then reviewed by the BASHH patient/public panel and posted on the BASHH website for public consultation. The final draft was piloted before publication. Guideline update The guidelines will be reviewed and revised in five years' time, 2022.

The Cost-Effectiveness of Syphilis Screening Among Men Who Have Sex With Men: An Exploratory Modeling Analysis

We adapted a published model to estimate the costs and benefits of screening men who have sex with men for syphilis, including the benefits of preventing syphilis-attributable human immunodeficiency virus. The cost per quality-adjusted life year gained by screening was <US $0 (cost-saving) and US $16,100 in the dynamic and static versions of the model, respectively.

Asymptomatic anorectal Chlamydia trachomatis and Neisseria gonorrhoeae infections are associated with systemic CD8+ T-cell activation

BACKGROUND

Oral preexposure prophylaxis (PrEP) has been established as a pivotal strategy in HIV prevention. However, bacterial sexually transmitted infections (STIs), such as Chlamydia trachomatis and Neisseria gonorrhoeae, are also highly prevalent. Although the presence of STI-related mucosal lesions is a known risk factor for HIV acquisition, the potential increase in risk associated with asymptomatic STIs is not completely understood. Recent data demonstrated higher T-cell activation is a risk factor for sexually acquired HIV-1 infection. We examined the effect of asymptomatic C. trachomatis and N. gonorrhoeae anorectal infection on systemic immune activation, potentially increasing the risk of HIV acquisition.

METHODS

We analyzed samples from participants of PrEP Brasil, a demonstration study of daily oral emtricitabine/tenofovir disoproxil fumarate HIV PrEP among healthy MSM, for T-cell activation by flow cytometry. We included 34 asymptomatic participants with anorectal swab for C. trachomatis and/or N. gonorrhoeae infection, whereas negative for other STIs, and 35 controls.

RESULTS

We found a higher frequency of human leukocyte antigen DRCD38 CD8 T cells (1.5 vs. 0.9%, P < 0.005) and with memory phenotype in the group with asymptomatic C. trachomatis and/or N. gonorrhoeae infection. Exhaustion and senescence markers were also significant higher in this group. No difference was observed in the soluble CD14 levels.

CONCLUSION

Our findings suggest asymptomatic anorectal C. trachomatis and/or N. gonorrhoeae increase systemic immune activation, potentially increasing the risk of HIV acquisition. Regular screening and treatment of asymptomatic STIs should be explored as adjuvant tools for HIV prevention.

The impact of HIV infection and socioeconomic factors on the incidence of gonorrhea: A county-level, US-wide analysis

Background

Gonorrhea is the second most commonly reported identifiable disease in the United States (U.S.). Importantly, more than 25% of gonorrheal infections demonstrate antibiotic resistance, leading the Centers for Disease Control and Prevention (CDC) to classify gonorrhea as an “urgent threat”.

Methods

We examined the association of gonorrhea infection rates with the incidence of HIV and socioeconomic factors. A county-level multivariable model was then constructed.

Results

Multivariable analysis demonstrated that HIV incidence [Coefficient (Coeff): 1.26, 95% Confidence Interval (CI): 0.86, 1.66, P<0.001] exhibited the most powerful independent association with the incidence of gonorrhea and predicted 40% of the observed variation in gonorrhea infection rates. Sociodemographic factors like county urban ranking (Coeff: 0.12, 95% CI: 0.03, 0.20, P = 0.005), percentage of women (Coeff: 0.41, 95% CI: 0.28, 0.53, P<0.001) and percentage of individuals under the poverty line (Coeff: 0.45, 95% CI: 0.32, 0.57, P<0.001) exerted a secondary impact. A regression model that incorporated these variables predicted 56% of the observed variation in gonorrhea incidence (Pmodel<0.001, R² model = 0.56).

Conclusions

Gonorrhea and HIV infection exhibited a powerful correlation thus emphasizing the benefits of comprehensive screening for sexually transmitted infections (STIs) and the value of pre-exposure prophylaxis for HIV among patients visiting an STI clinic. Furthermore, sociodemographic factors also impacted gonorrhea incidence, thus suggesting another possible focus for public health initiatives.

The PICASSO Cohort: baseline characteristics of a cohort of men who have sex with men and male-to-female transgender women at high risk for syphilis infection in Lima, Peru

BACKGROUND

Men who have sex with men (MSM) and male-to-female transgender women (transwomen) are disproportionately at risk of syphilis infection in Peru.

METHODS

From 2013 to 2014, MSM and transwomen seeking human immunodeficiency virus (HIV) or sexually transmitted infection (STI) testing and/or treatment were recruited into a 2-year observational cohort study to determine predictors of recently acquired syphilis infection (defined as a rapid plasma reagin [RPR] titer ≥1:16 and a reactive treponemal antibody test) in Lima, Peru. At baseline, interviewers collected sociodemographic, behavioral, and medical characteristics from participants. All cohort participants were tested for syphilis, HIV, Chlamydia trachomatis (CT), and Neisseria gonorrhoeae (NG) infection. Using cross-sectional analyses, bivariate and multivariate models were used to determine factors associated with recently acquired syphilis infection and calculate adjusted prevalence ratios.

RESULTS

We recruited 401 participants, 312 MSM and 89 transwomen, with median ages of 29.0 and 32.5 years old (interquartile ranges: 23.3, 37.4 and 27.2, 39.5, respectively). The prevalence of recently acquired syphilis infection at baseline was 16.8% for MSM and 6.7% for transwomen. Among MSM and transwomen, 30.1 and 33.7% were infected with HIV, 18.6 and 24.7% were infected with CT, and 14.2 and 19.1% were infected with NG, respectively. Co-infection rates among MSM with recently acquired syphilis infection included: 44.2% with HIV, 40.4% with CT (32.7% with anal CT and 7.7% with pharyngeal CT), and 19.2% with NG (11.5% with anal NG and 7.7% with pharyngeal NG). Co-infection rates among transwomen with recently acquired syphilis infection included: 66.7% with HIV, 0% with CT, and 16.7% with anal NG. In multivariate analysis among the entire cohort, recently acquired syphilis infection was independently associated with younger age (adjusted prevalence ratio [aPR] = 0.96, 95% confidence interval [CI] = 0.93-0.99), receptive role during anal sex (aPR = 2.56, 95% CI = 1.05-6.25), prior HIV diagnosis (aPR = 1.70, 95% CI = 1.11-2.61), anal CT or NG infection (aPR = 1.69, 95% CI = 1.09-2.60), and prior syphilis diagnosis (aPR = 3.53, 95% CI = 2.20-5.68).

CONCLUSIONS

We recruited a cohort of MSM and transwomen who had a high prevalence of recently acquired syphilis infection in Lima, Peru. Recently acquired syphilis infection was associated with socio-demographic characteristics, sexual risk, and sexually transmitted co-infections.

Factors associated with syphilis incidence in the HIV-infected in the era of highly active antiretrovirals

After several years of steady decline, syphilis is reemerging globally as a public health hazard, especially among people living with human immunodeficiency virus (HIV). Syphilis resurgence is observed mainly in men who have sex with men (MSM), yet other transmission groups are affected too. In this manuscript, we study the factors associated with syphilis incidence in the Swiss HIV cohort study in the era of highly effective antiretrovirals. Using parametric interval censored models with fixed and time-varying covariates, we studied the immunological, behavioral, and treatment-related elements associated with syphilis incidence in 3 transmission groups: MSM, heterosexuals, and intravenous drug users. Syphilis incidence has been increasing annually since 2005, with up to 74 incident cases per 1000 person-years in 2013, with MSM being the population with the highest burden (92% of cases). While antiretroviral treatment (ART) in general did not affect syphilis incidence, nevirapine (NVP) was associated with a lower hazard of syphilis incidence (multivariable hazard ratio 0.5, 95% confidence interval 0.2-1.0). We observed that condomless sex and younger age were associated with higher syphilis incidence. Moreover, time-updated CD4, nadir CD4, and CD8 cell counts were not associated with syphilis incidence. Finally, testing frequency higher than the recommended once a year routine testing was associated with a 2-fold higher risk of acquiring syphilis. Condomless sex is the main driver of syphilis resurgence in the Swiss HIV Cohort study; ART and immune reconstitution provide no protection against syphilis. This entails targeted interventions and frequent screening of high-risk populations. There is no known effect of NVP on syphilis; therefore, further clinical, epidemiological, and microbiological investigation is necessary to validate our observation.

Rates and Correlates of Syphilis Reinfection in Men Who Have Sex with Men

PURPOSE

This study examined rates and correlates of syphilis reinfection in men who have sex with men (MSM).

METHODS

From 2012 to 2015, time to reinfection was assessed in 323 MSM receiving initial treatment for syphilis in San Francisco.

RESULTS

One in five men was reinfected (71/323; 22%). The rate of syphilis reinfection was greater among HIV-infected men (adjusted hazard ratio [aHR] = 1.96; 95% confidence interval [95% CI] = 1.16-3.31) and ketamine users (aHR = 2.76; 95% CI = 1.09-7.00).

CONCLUSION

Expanded prevention efforts are needed with HIV-infected and substance-using MSM to reduce the burden of reinfection in this population.

HIV Incidence Among Men Who Have Sex With Men After Diagnosis With Sexually Transmitted Infections

BACKGROUND

Men who have sex with men (MSM) are at high risk for acquiring HIV infection after diagnosis with other sexually transmitted infections (STIs). Identifying the STIs associated with the greatest risk of subsequent HIV infection could help target prevention interventions, particularly preexposure prophylaxis (PrEP).

METHODS

Using matched HIV and STI surveillance data from Washington State from January 1, 2007, to June 30, 2013, we calculated the incidence of new HIV diagnoses after different STI diagnoses among MSM. Men entered observation at the time of their first STI diagnosis during the study period and exited at HIV diagnosis or June 30, 2013. Cox proportional hazards regression was used to conduct a global comparison of rates.

RESULTS

From January 1, 2007, to June 30, 2013, 6577 HIV-negative MSM were diagnosed as having 10,080 bacterial STIs at 8371 unique time points and followed for 17,419 person-years. Two hundred eighty (4.3%) men were subsequently diagnosed as having HIV infection for an overall incidence of 1.6 per 100 person-years (95% confidence interval, 1.4-1.8). The estimated incidence of HIV diagnoses among all MSM in the state was 0.4 per 100 person-years. Men who have sex with men were at the greatest risk for HIV diagnosis after being diagnosed as having rectal gonorrhea (HIV incidence, 4.1 per 100 person-years), followed by early syphilis (2.8), urethral gonorrhea (1.6), rectal chlamydial infection (1.6), pharyngeal gonorrhea (1.1), late syphilis (1.0), and urethral chlamydial infection (0.6; P < 0.0001 overall).

CONCLUSIONS

Men who have sex with men diagnosed as having rectal gonorrhea and early syphilis were at the greatest risk for being diagnosed as having HIV infection after STI diagnosis. These men should be prioritized for more intensive prevention interventions, including PrEP.

Syphilis and HIV/Syphilis Co-infection Among Men Who Have Sex With Men (MSM) in Ecuador

There is a reemergence of syphilis in the Latin American and Caribbean region. There is also very little information about HIV/Syphilis co-infection and its determinants. The aim of this study is to investigate knowledge, attitudes, and practices regarding sexually transmitted infections (STIs), in particular syphilis infection and HIV/Syphilis co-infection, as well as to estimate the prevalence of syphilis among men who have sex with men (MSM) in a city with one of the highest HIV prevalence rates in Ecuador. In this study, questionnaires were administered to 291 adult MSM. Questions included knowledge about STIs and their sexual practices. Blood samples were taken from participants to estimate the prevalence of syphilis and HIV/syphilis co-infection. In this population, the prevalence of HIV/syphilis co-infection was 4.8%, while the prevalence of syphilis as mono-infection was 6.5%. Participants who had syphilis mono-infection and HIV/syphilis co-infection were older. Men who had multiple partners and those who were forced to have sex had increased odds of syphilis and HIV/syphilis co-infection. A high prevalence of syphilis and self-reported STI was observed, which warrants targeted behavioral interventions. Co-infections are a cause for concern when treating a secondary infection in a person who is immunocompromised. These data suggest that specific knowledge, attitudes, and behaviors among MSM are associated with increased odds of STIs (including HIV/syphilis co-infections) in this region of Ecuador.

High Willingness to Use HIV Pre-Exposure Prophylaxis Among Transgender Women in Argentina

Purpose: In Argentina, transgender women face a disproportionately high prevalence of HIV infection (34%). Although not currently approved in Argentina, pre-exposure prophylaxis (PrEP) may offer a potential effective HIV prevention tool for this population. In this study, we assessed the willingness to use PrEP among transgender women in Argentina. Methods: Data were drawn from a nationwide cross-sectional survey conducted among transgender women in 2013. Using multivariable logistic regression, we assessed the prevalence of and factors associated with willingness to use PrEP among transgender women with negative or unknown HIV status. Results: This study included 337 transgender women (278 HIV negative and 59 with unknown HIV status), most of whom had a history of sex work involvement (81.8%). Overall, 301 (89.3%) expressed willingness to use PrEP. In a multivariable analysis, having casual sexual partners was positively associated with willingness to use PrEP (adjusted odds ratio [AOR]=4.26, 95% confidence interval [CI] 1.73-10.51), while discrimination by healthcare workers was negatively associated (AOR=0.33, 95% CI 0.12-0.88). Conclusion: We found high levels of willingness to use PrEP among transgender women in Argentina, suggesting that there is high perception of HIV risk in this population. However, discrimination by healthcare workers was a strong negative correlate of willingness to use PrEP, suggesting that multilevel interventions that address gender-based stigma in healthcare settings will be critical for the success of PrEP as an HIV prevention strategy in this population.

High HIV incidence in men who have sex with men following an early syphilis diagnosis: is there room for pre-exposure prophylaxis as a prevention strategy?

OBJECTIVES

HIV pre-exposure prophylaxis (PrEP) is becoming a pivotal strategy for HIV prevention. Understanding the impact of risk factors for HIV transmission to identify those at highest risk would favour the implementation of PrEP, currently limited by costs. In this service evaluation, we estimated the incidence of bacterial STIs in men who have sex with men (MSM) diagnosed with early syphilis attending a London sexual health clinic according to their HIV status. In addition, we estimated the incidence of HIV infection in HIV-negative MSM, following a diagnosis of early syphilis.

METHODS

We undertook a retrospective case note review of all MSM patients diagnosed with early syphilis between January and June 2014. A number of sexual health screens and diagnoses of chlamydia, gonorrhoea and HIV were prospectively analysed following the syphilis diagnosis.

RESULTS

206 MSM were diagnosed with early syphilis. 110 (53%) were HIV-negative at baseline, 96 (47%) were HIV-positive. Only age (37 vs 32 years, p=0.0005) was significantly different according to HIV status of MSM at baseline. In HIV-negative versus HIV-positive MSM, incidence of rectal chlamydia infection at follow-up was 27 cases vs 50/100 person-years of follow-up (PYFU) (p=0.0039), 33 vs 66/100 PYFU (p=0.0044) for rectal gonorrhoea and 10 vs 26/100 PYFU (p=0.0044) for syphilis reinfection, respectively. Total follow-up for 110 HIV-negative MSM was 144 person-years. HIV incidence was 8.3/100 PYFU (CI 4.2 to 14).

CONCLUSIONS

A diagnosis of early syphilis carries a high risk of consequent HIV seroconversion and should warrant prioritised access to prevention measures such as PrEP and regular STI screening to prevent HIV transmission.

Global challenges in human immunodeficiency virus and syphilis coinfection among men who have sex with men

INTRODUCTION

Syphilis and human immunodeficiency virus (HIV) coinfection disproportionately affects men who have sex with men (MSM), and the rate of coinfection has been increasing over the last decade. HIV and syphilis coinfection is particularly challenging because the infections interact synergistically thereby increasing the risk of acquisition and transmission as well as accelerating disease progression. Areas covered: This paper reviews and summarizes the epidemiology, pathogenesis, diagnosis, clinical management and prevention of HIV and syphilis coinfection among MSM. Expert commentary: Research does not support a different syphilis treatment for coinfected individuals; however, coinfection may warrant a recommendation for antiretroviral therapy. In order to reverse the epidemic of syphilis and HIV coinfection, there needs to be greater awareness, improved cultural sensitivity among health care providers, improved access to preventative services and increased screening for syphilis and HIV.

Risk Factors Associated with Incident Syphilis in a Cohort of High-Risk Men in Peru

BACKGROUND

Syphilis is concentrated among high-risk groups, but the epidemiology of syphilis reinfection is poorly understood. We characterized factors associated with syphilis incidence, including reinfection, in a high-risk cohort in Peru.

METHODS

Participants in the NIMH CPOL trial were assessed at baseline and 2 annual visits with HIV/STI testing and behavioral surveys. Participants diagnosed with syphilis also attended 4- and 9-month visits. All participants underwent syphilis testing with RPR screening and TPPA confirmation. Antibiotic treatment was provided according to CDC guidelines. Reinfection was defined as a 4-fold titer increase or recurrence of seroreactivity after successful treatment with subsequent negative RPR titers. The longitudinal analysis used a Possion generalized estimating equations model with backward selection of variables in the final model (criteria P <0.02).

RESULTS

Of 2,709 participants, 191 (7.05%) were RPR-reactive (median 1:8, range 1:1-1:1024) with TPPA confirmation. There were 119 total cases of incident syphilis, which included both reinfection and first-time incident cases. In the bivariate analysis, the oldest 2 quartiles of age (incidence ratio (IR) 3.84; P <0.001 and IR 8.15; P <0.001) and being MSM/TW (IR 6.48; P <0.001) were associated with higher risk of incident syphilis infection. Of the sexual risk behaviors, older age of sexual debut (IR 12.53; P <0.001), not being in a stable partnership (IR 1.56, P = 0.035), higher number of sex partners (IR 3.01; P <0.001), unprotected sex in the past 3 months (IR 0.56; P = 0.003), HIV infection at baseline (IR 3.98; P <0.001) and incident HIV infection during the study period (IR 6.26; P = 0.003) were all associated with incident syphilis. In the multivariable analysis, older age group (adjusted incidence ratio (aIR) 6.18; P <0.001), men reporting having sex with a man (aIR 4.63; P <0.001), and incident HIV infection (aIR 4.48; P = 0.008) were significantly associated.

CONCLUSIONS

We report a high rate of syphilis reinfection among high-risk men who have evidence of previous syphilis infection. Our findings highlight the close relationship between HIV incidence with both incident syphilis and syphilis reinfection. Further studies on syphilis reinfection are needed to understand patterns of syphilis reinfection and new strategies beyond periodic testing of high-risk individuals based on HIV status are needed.

Evaluation of Elecsys Syphilis Assay for Routine and Blood Screening and Detection of Early Infection

Treponema pallidum infections can have severe complications if not diagnosed and treated at an early stage. Screening and diagnosis of syphilis require assays with high specificity and sensitivity. The Elecsys Syphilis assay is an automated treponemal immunoassay for the detection of antibodies against T. pallidum The performance of this assay was investigated previously in a multicenter study. The current study expands on that evaluation in a variety of diagnostic settings and patient populations, at seven independent laboratories. The samples included routine diagnostic samples, blood donation samples, samples from patients with confirmed HIV infections, samples from living organ or bone marrow donors, and banked samples, including samples previously confirmed as syphilis positive. This study also investigated the seroconversion sensitivity of the assay. With a total of 1,965 syphilis-negative routine diagnostic samples and 5,792 syphilis-negative samples collected from blood donations, the Elecsys Syphilis assay had specificity values of 99.85% and 99.86%, respectively. With 333 samples previously identified as syphilis positive, the sensitivity was 100% regardless of disease stage. The assay also showed 100% sensitivity and specificity with samples from 69 patients coinfected with HIV. The Elecsys Syphilis assay detected infection in the same bleed or earlier, compared with comparator assays, in a set of sequential samples from a patient with primary syphilis. In archived serial blood samples collected from 14 patients with direct diagnoses of primary syphilis, the Elecsys Syphilis assay detected T. pallidum antibodies for 3 patients for whom antibodies were not detected with the Architect Syphilis TP assay, indicating a trend for earlier detection of infection, which may have the potential to shorten the time between infection and reactive screening test results.

Transgender populations and HIV: unique risks, challenges and opportunities

Due to unique social, behavioural, structural and biological issues, transgender (TG) populations, especially TG women, are at high risk for HIV acquisition. This increased risk is multifactorial, due to differing psychosocial risk factors, poorer access to TG-specific healthcare, a higher likelihood of using exogenous hormones or fillers without direct medical supervision, interactions between hormonal therapy and antiretroviral therapy, and direct effects of hormonal therapy on HIV acquisition and immune control. Further research is needed to elucidate these mechanisms of risk and to help design interventions to reduce HIV risk among transgender populations.

The Transition From Postexposure Prophylaxis to Preexposure Prophylaxis: An Emerging Opportunity for Biobehavioral HIV Prevention

Although some individuals who present for antiretroviral postexposure prophylaxis (PEP) had a 1-time exposure to human immunodeficiency virus (HIV), others may be recurrently risky. Given that preexposure prophylaxis (PrEP) has been shown to be efficacious, identification of those individuals who present for PEP who might benefit from PrEP is important to decrease HIV acquisition in high-risk individuals. While inclusion criteria for PrEP have been developed, there is a paucity of data to help clinicians determine which PEP users are at highest risk for HIV acquisition and therefore should be offered PrEP. We will discuss the rationale for using PrEP after PEP use, and will focus on the assessment of PEP users who may benefit from PrEP.

Benzathine penicillin G for the management of early syphilis among HIV co-infected persons: A systematic review

Background

The optimal treatment for syphilis in people who are human immunodeficiency virus (HIV) positive is controversial.

Objective

To assess the efficacy of three doses versus a single dose of long acting Benzathine Penicillin G (BP-G) for the effective management of early syphilis among HIV co-infected populations.

Methods

A systematic search of the published literature was conducted using MEDLINE and EMBASE databases to identify clinical and observational studies published between January 2010 and May 2015. Inclusion criteria were: publication in English or French, populations co-infected with HIV and early syphilis, treatment with BP-G and outcomes related to syphilis treatment. All articles underwent a risk of bias assessment and data extraction was completed on all included studies.

Results

Seven studies were eligible for final inclusion, data extraction and analysis. The evidence from the final included studies were from non-randomized controlled trials. In general, no significant differences were found between groups treated with one versus two or more doses of BP-G; but there was a trend toward longer time to treatment failure with three doses. Differences in methodology limit the ability to draw any firm conclusions on the relative efficacy between these two treatment regimens.

Conclusion

Insufficient data exist to ascertain whether or not there is an added benefit from additional doses of BP-G for the treatment of early syphilis with HIV co-infection. A high-quality, randomized controlled trial is needed to definitively nswer this question.