In spite of its immutable susceptibility to penicillin,Treponema pallidum(T.pallidum) subsp.pallidumcontinues to cause millions of cases of syphilis each year worldwide, resulting in significant morbidity and mortality and underscoring the urgency of developing an effective vaccine to curtail the spread of the infection. Several technical challenges, including absence of anin vitroculture system until very recently, have hampered efforts to catalog the diversity of strains collected worldwide. Here, we provide near-complete genomes from 196T.pallidumstrains–including 191T.pallidumsubsp.pallidum–sequenced directly from patient samples collected from 8 countries and 6 continents. Maximum likelihood phylogeny revealed that samples from most sites were predominantly SS14 clade. However, 99% (84/85) of the samples from Madagascar formed two of the five distinct Nichols subclades. Although recombination was uncommon in the evolution of modern circulating strains, we found multiple putative recombination events betweenT.pallidumsubsp.pallidumand subsp.endemicum, shaping the genomes of several subclades. Temporal analysis dated the most recent common ancestor of Nichols and SS14 clades to 1717 (95% HPD: 1543–1869), in agreement with other recent studies. Rates of SNP accumulation varied significantly among subclades, particularly among different Nichols subclades, and was associated in the Nichols A subclade with a C394F substitution in TP0380, a ERCC3-like DNA repair helicase. Our data highlight the role played by variation in genes encoding putative surface-exposed outer membrane proteins in defining separate lineages, and provide a critical resource for the design of broadly protective syphilis vaccines targeting surface antigens.

Background: HIV disproportionally affects key populations including men who have sex with men (MSM). HIV prevalence among MSM varies from 17% in Brazil and Mexico to 13% in Peru, whereas it is below 0.5% for the general population in each country. Pre-exposure prophylaxis (PrEP) with emtricitabine/tenofovir is being implemented in the context of combination HIV prevention. Reports on willingness to use PrEP among MSM have started to emerge over the last few years. Previously reported factors associated with willingness to use PrEP include awareness, higher sexual risk behavior, and previous sexually transmitted infection. Objective: This study aimed to evaluate the factors associated with willingness to use daily oral PrEP among MSM in 3 Latin American, middle-income countries (Brazil, Mexico, and Peru). Methods: This Web-based, cross-sectional survey was advertised in 2 gay social network apps (Grindr and Hornet) used by MSM to find sexual partners and on Facebook during 2 months in 2018. Inclusion criteria were being 18 years or older, cisgender men, and HIV-negative by self-report. Eligible individuals answered questions on demographics, behavior, and PrEP (awareness, willingness to use, barriers, and facilitators). Multivariable logistic regression modeling was performed to assess the factors associated with willingness to use daily oral PrEP in each country. Results: From a total sample of 43,687 individuals, 44.54% of MSM (19,457/43,687) were eligible and completed the Web-based survey—Brazil: 58.42% (11,367/19,457), Mexico: 30.50% (5934/19,457), and Peru: 11.08% (2156/19,457); median age was 28 years (interquartile range: 24-34), and almost half lived in large urban cities. Most participants were recruited on Grindr (69%, 13,349/19,457). Almost 20% (3862/19,352) had never tested for HIV, and condomless receptive anal sex was reported by 40% (7755/19,326) in the previous 6 months. Whereas 67.51% (13,110/19,376) would be eligible for PrEP, only 9.80% (1858/18,959) of participants had high HIV risk perception. PrEP awareness was reported by 64.92% (12,592/19,396); this was lower in Peru (46.60%, 1002/2156). Overall, willingness to use PrEP was reported by 64.23% (12,498/19,457); it was highest in Mexico (70%, 4158/5934) and lowest in Peru (58%, 1241/2156). In multivariate regression models adjusted for age, schooling, and income in each country, willingness to use PrEP was positively associated with PrEP awareness and PrEP facilitators (eg, free PrEP and HIV testing) and negatively associated with behavioral (eg, concerned by daily pill regimen) and belief barriers (eg, sexual partners may expect condomless sex). Conclusions: In this first cross-country, Web-based survey in Latin America, willingness to use PrEP was found to be high and directly related to PrEP awareness. Interventions to increase awareness and PrEP knowledge about safety and efficacy are crucial to increase PrEP demand. This study provides important information to support the implementation of PrEP in Brazil, Mexico, and Peru.

Background: Men who have sex with men (MSM) and male-to-female transgender women (TW) are at increased risk of HIV and sexually transmitted infections (STIs). We evaluated factors associated with incidence of HIV, HSV-2, and chlamydia and gonorrhea (anal and pharyngeal). Methods: We used data from the Comunidades Positivas trial with MSM/TW who have sex with men in Lima, Peru. Participants were asked about sexual risk behaviors and underwent HIV/STI testing at baseline and 9- and 18-month follow-ups. We used discrete time proportional hazards regression to calculate hazard ratios for variables associated with incidence of each STI. Results: Among 718 MSM/TW, HIV incidence was 3.6 cases per 100 person-years. HIV incidence was associated with having an incident STI adjusted hazard ratio (aHR) of 3.73. Unprotected receptive anal intercourse was associated with incident anal chlamydia (aHR 2.20). An increased number of sexual partners increased incident HSV-2 (aHR 3.15 for 6–14 partners and 3.97 for 15–46 partners compared with 0–2 partners). The risk of anal gonorrhea decreased with each sexually active year (aHR 0.94) and increased for unprotected compensated sex (aHR 2.36). The risk of pharyngeal gonorrhea also decreased with each year since sexual debut (aHR 0.95). The risk of anal chlamydia decreased with each sexually active year (aHR 0.96); the risk increased with reports of unprotected sex work (aHR 1.61) and unprotected receptive anal sex (aHR 2.63). All aHRs have P values <0.05. Conclusions: MSM/TW experience high incidence of HIV. Up-to-date prevalence and incidence information and identifying factors associated with infection can help develop a more effective combination prevention response.

Introduction: The HIV epidemic continues to disproportionately impact Latin‐American transgender women (TGW). We assessed factors associated with long‐term pre‐exposure prophylaxis (PrEP) engagement and adherence among TGW enrolled in the Implementation of PrEP (ImPrEP) study, the largest PrEP demonstration study in Latin America.Methods: HIV‐negative TGW aged ≥18 years reporting 1+eligibility criteria in the 6 months prior to enrolment (e.g. sex partner known to be living with HIV, condomless anal sex [CAS], transactional sex or having a sexually transmitted infection [STI]) who could safely take PrEP were enrolled. Follow‐up visits were conducted at 4 weeks and then quarterly. We conducted logistic regression to identify factors associated with long‐term PrEP engagement (3+ follow‐up visits in 52 weeks) and complete self‐reported adherence (no missed pills in the past 30 days) during follow‐up. For both outcomes, we constructed multivariable models controlling for country, socio‐demographics, sexual behaviour, substance use, STIs and self‐reported adherence at 4 weeks (long‐term engagement outcome only).Results: From March 2018 to June 2021, ImPrEP screened 519 TGW, enrolled 494 (Brazil: 190, Mexico: 66 and Peru: 238) and followed them for 52 weeks. At baseline, 27.5% of TGW were aged 18–24 years, 67.8% were mixed‐race and 31.6% had >secondary education. Most, 89.9% reported CAS, 61.9% had >10 sex partners and 71.9% reported transactional sex. HIV incidence was 1.82 cases per 100 person‐years (95% confidence interval [CI]: 0.76–4.38). Almost half of TGW (48.6%) had long‐term PrEP engagement, which was positively associated with reporting complete adherence at week 4 (aOR:2.94 [95%CI:1.88–4.63]) and was inversely associated with reporting CAS with unknown‐HIV partner (aOR:0.52 [95%CI:0.34–0.81]), migration (aOR:0.54 [95%CI:0.34–0.84]), and being from Mexico (aOR:0.28 [95%CI:0.14–0.53]). Self‐reported adherence was associated with TGW aged >34 (aOR:1.61 [95%CI:1.10–2.34]) compared to those aged 25–34 and those with >secondary education (aOR:1.55 [95%CI:1.10–2.19]) and was lower among TGW from Peru (aOR:0.29 [95%CI:0.21–0.41]) or reporting PrEP‐related adverse effects (aOR:0.63 [95%CI:0.42–0.92]).Conclusions: Although TGW were willing to enrol in ImPrEP, long‐term PrEP engagement and complete self‐reported adherence were limited, and HIV incidence remained relatively high. A successful HIV prevention agenda should include trans‐specific interventions supporting oral PrEP and exploring long‐acting PrEP strategies for TGW.

Background: Most forcibly displaced persons are hosted in low- and middle-income countries (LMIC). There is a growing urbanization of forcibly displaced persons, whereby most refugees and nearly half of internally displaced persons live in urban areas. This scoping review assesses the sexual and reproductive health (SRH) needs, outcomes, and priorities among forcibly displaced persons living in urban LMIC. Methods: Following The Joanna Briggs Institute scoping review methodology we searched eight databases for literature published between 1998 and 2023 on SRH needs among urban refugees in LMIC. SHR was operationalized as any dimension of sexual health (comprehensive sexuality education [CSE]; sexual and gender based violence [GBV]; HIV and STI prevention and control; sexual function and psychosexual counseling) and/or reproductive health (antental, intrapartum, and postnatal care; contraception; fertility care; safe abortion care). Searches included peer-reviewed and grey literature studies across quantitative, qualitative, or mixed-methods designs. Findings: The review included 92 studies spanning 100 countries: 55 peer-reviewed publications and 37 grey literature reports. Most peer-reviewed articles (n = 38) discussed sexual health domains including: GBV (n = 23); HIV/STI (n = 19); and CSE (n = 12). Over one-third (n = 20) discussed reproductive health, including: antenatal, intrapartum and postnatal care (n = 13); contraception (n = 13); fertility (n = 1); and safe abortion (n = 1). Eight included both reproductive and sexual health. Most grey literature (n = 29) examined GBV vulnerabilities. Themes across studies revealed social-ecological barriers to realizing optimal SRH and accessing SRH services, including factors spanning structural (e.g., livelihood loss), health institution (e.g., lack of health insurance), community (e.g., reduced social support), interpersonal (e.g., gender inequitable relationships), and intrapersonal (e.g., low literacy) levels. Conclusions: This review identified displacement processes, resource insecurities, and multiple forms of stigma as factors contributing to poor SRH outcomes, as well as producing SRH access barriers for forcibly displaced individuals in urban LMIC. Findings have implications for mobilizing innovative approaches such as self-care strategies for SRH (e.g., HIV self-testing) to address these gaps. Regions such as Africa, Latin America, and the Caribbean are underrepresented in research in this review. Our findings can guide SRH providers, policymakers, and researchers to develop programming to address the diverse SRH needs of urban forcibly displaced persons in LMIC. Plain English summary: Most forcibly displaced individuals live in low- and middle-income countries (LMICs), with a significant number residing in urban areas. This scoping review examines the sexual and reproductive health (SRH) outcomes of forcibly displaced individuals in urban LMICs. We searched eight databases for relevant literature published between 1998 and 2023. Inclusion criteria encompassed peer-reviewed articles and grey literature. SRH was defined to include various dimensions of sexual health (comprehensive sexuality education; sexual and gender-based violence; HIV/ STI prevention; sexual function, and psychosexual counseling) and reproductive health (antenatal, intrapartum, and postnatal care; contraception; fertility care; and safe abortion care). We included 90 documents (53 peer-reviewed articles, 37 grey literature reports) spanning 100 countries. Most peer-reviewed articles addressed sexual health and approximately one-third centered reproductive health. The grey literature primarily explored sexual and gender-based violence vulnerabilities. Identified SRH barriers encompassed challenges across structural (livelihood loss), health institution (lack of insurance), community (reduced social support), interpersonal (gender inequities), and individual (low literacy) levels. Findings underscore gaps in addressing SRH needs among urban refugees in LMICs specifically regarding sexual function, fertility care, and safe abortion, as well as regional knowledge gaps regarding urban refugees in Africa, Latin America, and the Caribbean. Self-care strategies for SRH (e.g., HIV self-testing, long-acting self-injectable contraception, abortion self-management) hold significant promise to address SRH barriers experienced by urban refugees and warrant further exploration with this population. Urgent research efforts are necessary to bridge these knowledge gaps and develop tailored interventions aimed at supporting urban refugees in LMICs.

HIV incidence estimation is critical for monitoring the HIV epidemic dynamics and the effectiveness of public health prevention interventions. We aimed to identify sexual and gender minorities (SGM) with recent HIV infections, factors associated with recent HIV infection, and to estimate annualised HIV incidence rates. Cross-sectional multicentre study in HIV testing services in Brazil and Peru (15 cities). Inclusion criteria: 18+ years, SGM assigned male at birth, not using pre-/post-exposure prophylaxis. We identified recent HIV infection using the Maxim HIV-1 LAg-Avidity EIA assay as part of a recent infection testing algorithm (RITA). Annualized HIV incidence was calculated using the UNAIDS/WHO incidence estimator tool. Multivariable logistic regression models were used to estimate factors associated with recent HIV infection. Trial registration: NCT05674682. From 31-Jan-2021 to 29-May-2022, 6899 individuals participated [Brazil: 4586 (66.5%); Peru: 2313 (33.5%)]; 5946 (86.2%) cisgender men, 751 (10.9%) transgender women and 202 (2.9%) non-binary/gender diverse. Median age was 27 (IQR: 23–34) years. HIV prevalence was 11.4% (N = 784/6899); 137 (2.0%) SGM were identified with recent HIV infection. The overall annualized HIV incidence rate was 3.88% (95% CI: 2.86–4.87); Brazil: 2.62% (95% CI: 1.78–3.43); Peru: 6.69% (95% CI: 4.62–8.69). Participants aged 18–24 years had higher odds of recent HIV infection compared to those aged 30+ years in both countries. Our results highlight the significant burden of HIV epidemic among SGM in large urban centres of Brazil and Peru. Public health policies and interventions to increase access to effective HIV prevention methods such as PrEP are urgently needed in Latin America. Unitaid, 10.13039/100004423 WHO (Switzerland), 10.13039/100009647 Ministry of Health from Brazil and Peru.