Background In 2007 the World Health Organization (WHO) launched the global initiative to eliminate mother-to-child transmission of syphilis (congenital syphilis, or CS). To assess progress towards the goal of <50 CS cases per 100,000 live births, we generated regional and global estimates of maternal and congenital syphilis for 2016 and updated the 2012 estimates. Methods Maternal syphilis estimates were generated using the Spectrum-STI model, fitted to sentinel surveys and routine testing of pregnant women during antenatal care (ANC) and other representative population data. Global and regional estimates of CS used the same approach as previous WHO estimates. Results The estimated global maternal syphilis prevalence in 2016 was 0.69% (95% confidence interval: 0.57–0.81%) resulting in a global CS rate of 473 (385–561) per 100,000 live births and 661,000 (538,000–784,000) total CS cases, including 355,000 (290,000–419,000) adverse birth outcomes (ABO) and 306,000 (249,000–363,000) non-clinical CS cases (infants without clinical signs born to un-treated mothers). The ABOs included 143,000 early fetal deaths and stillbirths, 61,000 neonatal deaths, 41,000 preterm or low-birth weight births, and 109,000 infants with clinical CS. Of these ABOs– 203,000 (57%) occurred in pregnant women attending ANC but not screened for syphilis; 74,000 (21%) in mothers not enrolled in ANC, 55,000 (16%) in mothers screened but not treated, and 23,000 (6%) in mothers enrolled, screened and treated. The revised 2012 estimates were 0.70% (95% CI: 0.63–0.77%) maternal prevalence, and 748,000 CS cases (539 per 100,000 live births) including 397,000 (361,000–432,000) ABOs. The estimated decrease in CS case rates between 2012 and 2016 reflected increased access to ANC and to syphilis screening and treatment. Conclusions Congenital syphilis decreased worldwide between 2012 and 2016, although maternal prevalence was stable. Achieving global CS elimination, however, will require improving access to early syphilis screening and treatment in ANC, clinically monitoring all women diagnosed with syphilis and their infants, improving partner management, and reducing syphilis prevalence in the general population by expanding testing, treatment and partner referral beyond ANC.

The AIDS epidemic in Brazil is disproportionately concentrated among MSM, as has been found in other countries. Renewed efforts to encourage testing, prevention and treatment are required.

One of the many challenges hindering the global response to the human immunodeficiency virus (HIV)/acquired immunodeficiency syndrome (AIDS) epidemic is the difficulty of collecting reliable information about the populations most at risk for the disease. Thus, the authors empirically assessed a promising new method for estimating the sizes of most at-risk populations: the network scale-up method. Using 4 different data sources, 2 of which were from other researchers, the authors produced 5 estimates of the number of heavy drug users in Curitiba, Brazil. The authors found that the network scale-up and generalized network scale-up estimators produced estimates 5–10 times higher than estimates made using standard methods (the multiplier method and the direct estimation method using data from 2004 and 2010). Given that equally plausible methods produced such a wide range of results, the authors recommend that additional studies be undertaken to compare estimates based on the scale-up method with those made using other methods. If scale-up-based methods routinely produce higher estimates, this would suggest that scale-up-based methods are inappropriate for populations most at risk of HIV/AIDS or that standard methods may tend to underestimate the sizes of these populations.

BackgroundBenzathine penicillin G (BPG) is the only recommended treatment to prevent mother-to-child transmission of syphilis. Due to recent reports of country-level shortages of BPG, an evaluation was undertaken to quantify countries that have experienced shortages in the past 2 years and to describe factors contributing to these shortages.Methods and findingsCountry-level data about BPG shortages were collected using 3 survey approaches. First, a survey designed by the WHO Department of Reproductive Health and Research was distributed to 41 countries and territories in the Americas and 41 more in Africa. Second, WHO conducted an email survey of 28 US Centers for Disease Control and Prevention country directors. An additional 13 countries were in contact with WHO for related congenital syphilis prevention activities and also reported on BPG shortages. Third, the Clinton Health Access Initiative (CHAI) collected data from 14 countries (where it has active operations) to understand the extent of stock-outs, in-country purchasing, usage behavior, and breadth of available purchasing options to identify stock-outs worldwide. CHAI also conducted in-person interviews in the same 14 countries to understand the extent of stock-outs, in-country purchasing and usage behavior, and available purchasing options. CHAI also completed a desk review of 10 additional high-income countries, which were also included. BPG shortages were attributable to shortfalls in supply, demand, and procurement in the countries assessed. This assessment should not be considered globally representative as countries not surveyed may also have experienced BPG shortages. Country contacts may not have been aware of BPG shortages when surveyed or may have underreported medication substitutions due to desirability bias. Funding for the purchase of BPG by countries was not evaluated. In all, 114 countries and territories were approached to provide information on BPG shortages occurring during 2014–2016. Of unique countries and territories, 95 (83%) responded or had information evaluable from public records. Of these 95 countries and territories, 39 (41%) reported a BPG shortage, and 56 (59%) reported no BPG shortage; 10 (12%) countries with and without BPG shortages reported use of antibiotic alternatives to BPG for treatment of maternal syphilis. Market exits, inflexible production cycles, and minimum order quantities affect BPG supply. On the demand side, inaccurate forecasts and sole sourcing lead to under-procurement. Clinicians may also incorrectly prescribe BPG substitutes due to misperceptions of quality or of the likelihood of adverse outcomes.ConclusionsTargets for improvement include drug forecasting and procurement, and addressing provider reluctance to use BPG. Opportunities to improve global supply, demand, and use of BPG should be prioritized alongside congenital syphilis elimination efforts.

BackgroundThe Brazilian response towards AIDS epidemic is well known, but the absence of a systematic review of vulnerable populations ─ men who have sex with men (MSM), female sex workers (FSW), and drug users (DU) remains a main gap in the available literature. Our goal was to conduct a systematic review and meta-analysis of studies assessing HIV prevalence among MSM, FSW and DU, calculating a combined pooled prevalence and summarizing factors associated the pooled prevalence for each group.MethodsNine electronic databases (MEDLINE via PubMed, EMBASE, Cochrane CENTRAL, AIDSLINE, AMED, CINAHL, TOXNET, SciELO, and ISI-Web of Science) were searched for peer-reviewed papers published in English, French, Spanish or Portuguese, from 1999 to 2009. To be included in the review, studies had to measure HIV prevalence and/or incidence as the primary outcome among at least one specific population under analysis.ResultsThe studies targeting the three populations analyzed mostly young participants aged 30 years or less. Among FSW, eight studies were selected (3,625 participants), consistently identifying higher condom use with sexual clients than with occasional and stable partners. The combined HIV prevalence for FSW was 6.2 (95% CI: 4.4-8.3). Ten studies targeting MSM were identified (6,475 participants). Unprotected anal intercourse was commonly reported on those studies, but with great variability according to the nature of the relationship - stable vs. occasional sex partners - and sexual practice - receptive vs. insertive anal sex. Pooled HIV prevalence for MSM was 13.6 (95% CI: 8.2-20.2). Twenty nine studies targeting DU were identified (13,063 participants). Those studies consistently identified injection drug use and syringe/needle sharing as key predictors of HIV-infection, as well as engagement in sex work and male-to-male sex. The combined HIV prevalence across studies targeting DU was 23.1 (95% CI: 16.7-30.2).ConclusionsFSW, MSM and DU from Brazil have a much risk of acquiring HIV infection compared to the general population, among which HIV prevalence has been relatively low (~0.6%). Those vulnerable populations should be targeted by focused prevention strategies that provide accurate information, counseling and testing, as well as concrete means to foster behavior change (e.g. access to condoms, drug abuse treatment, and clean syringes in the case of active injecting drug users), tailored to gender and culture-specific needs. Programs that provide these services need to be implemented on public health services throughout the country, in order to decrease the vulnerability of those populations to HIV infection.