Background Prevention of bacterial sexually transmitted infections (STIs) among men who have sex with men (MSM) requires timely disease detection, but this is complicated by asymptomatic infection. We estimated screening/testing rates by symptomatic status to evaluate adherence to Centers for Disease Control and Prevention STI screening guidelines. Methods In a cross-sectional study of 2572 US MSM aged 15 to 65 years in 2017 to 2018, we measured the reported number of asymptomatic STI screens in the past 2 years versus tests prompted by disease symptoms. Using negative binominal regression within a hierarchical Bayesian framework, we estimated yearly rates of asymptomatic screening and symptomatic testing by geographic, demographic, and behavioral factors. Results Human immunodeficiency virus (HIV) status was most strongly associated with all testing/screening frequency (incidence rate ratio [IRR], 1.72; 95% credible interval [Crl], 1.49, 1.97). The HIV-uninfected MSM had 0.14 (95% credible interval [CrI], 0.12-0.17) symptomatic tests and 0.88 (95% CrI, 0.77-1.01) asymptomatic screens per year. The HIV-infected MSM had 0.25 (95% CrI, 0.18-0.35) symptomatic tests and 1.53 (95% CrI, 1.24-1.88) asymptomatic screens per year. Rates of asymptomatic screening were higher among black compared with white MSM (IRR, 1.41; 95% CrI, 1.15-1.73), but weakly associated with number of past-year sexual partners (IRR, 1.01; 95% CrI, 1.00-1.01). Overall, 85% to 90% of diagnostic events were asymptomatic screens. Conclusions Self-reported rates of STI screening were close to Centers for Disease Control and Prevention's recommended overall annual screening frequency, but with gaps defined by demographics and behavioral risk. Targeted screening efforts may be indicated specifically for younger MSM and those with multiple partners.

In this paper, we present an overview and descriptive results from the first egocentric network study of men who have sex with men (MSM) from across the United States: the ARTnet study. ARTnet was designed to support prevention research for human immunodeficiency virus (HIV) and other sexually transmitted infections (STIs) that are transmitted across partnership networks. ARTnet implemented a population-based egocentric network study design that sampled egos from the target population and asked them to report on the number, attributes, and timing of their sexual partnerships. Such data provide the foundation needed for parameterizing stochastic network models that are used for disease projection and intervention planning. ARTnet collected data online from 2017 to 2019, with a final sample of 4904 participants who reported on 16198 sexual partnerships. The aims of this paper were to characterize the joint distribution of three network parameters needed for modeling: degree distributions, assortative mixing, and partnership age, with heterogeneity by partnership type (main, casual and one-time), demography, and geography. Participants had an average of 1.19 currently active partnerships (“mean degree”), which was higher for casual partnerships (0.74) than main partnerships (0.45). The mean rate of one-time partnership acquisition was 0.16 per week (8.5 partners per year). Main partnerships lasted 272.5 weeks on average, while casual partnerships lasted 133.0 weeks. There was strong but heterogenous assortative mixing by race/ethnicity for all groups. The mean absolute age difference for all partnership types was 9.5 years, with main partners differing by 6.3 years compared to 10.8 years for casual partners. Our analysis suggests that MSM may be at sustained risk for HIV/STI acquisition and transmission through high network degree of sexual partnerships. The ARTnet network study provides a robust and reproducible foundation for understanding the dynamics of HIV/STI epidemiology among U.S. MSM and supporting the implementation science that seeks to address persistent challenges in HIV/STI prevention.

BACKGROUND: Sexually transmitted infections (STIs) are associated with an increased risk of human immunodeficiency virus (HIV) acquisition and transmission. We estimated the proportion of HIV incidence among men who have sex with men attributable to infection with the 2 most common bacterial STIs, Neisseria gonorrhoeae (NG) and Chlamydia trachomatis (CT). METHODS: We used a stochastic, agent-based model of a sexual network of MSM with cocirculating HIV, NG, and CT infections. Relative risk (RR) multipliers, specific to anatomic site of infection, modified the risk of HIV transmission and acquisition based on STI status. We estimated the effect of NG and CT on HIV incidence overall and on HIV acquisition and HIV transmission separately. Each scenario was simulated for 10 years. The population attributable fraction (PAF) was determined for each combination of RRs by comparing the incidence in the final year of a scenario to a scenario in which the RRs associated with NG and CT were set to 1.0. RESULTS: Overall, 10.2% (interquartile range [IQR], 7.9-12.4) of HIV infections were attributable to NG/CT infection. Then in sensitivity analyses, the PAF for HIV transmission ranged from 3.1% (IQR, 0.5-5.2) to 20.4% (IQR, 17.8-22.5) and the PAF for HIV acquisition ranged from 2.0% (IQR, -0.7 to 4.3) to 13.8% (IQR, 11.7-16.0). CONCLUSIONS: Despite challenges in estimating the causal impact of NG/CT on HIV risk, modeling is an alternative approach to quantifying plausible ranges of effects given uncertainty in the biological cofactors. Our estimates represent idealized public health interventions in which STI could be maximally prevented, setting targets for real-world STI interventions that seek to reduce HIV incidence.

During pregnancy and postpartum, women in high HIV prevalence regions continue to be at high risk for acquiring HIV, due to both behavioral and biological mechanisms, despite declines in coital frequency as a pregnancy advances. We estimated differences in rates of partnership concurrency for men with and without pregnant or postpartum sexual partners. We used monthly retrospective panel data from Ghana from three perspectives: couple-level data, female reports of pregnancy and male partner concurrency, and male reports of concurrent partnerships and female partner pregnancy. Coital frequency increased during the first trimester and then declined with advancing pregnancy. However, in all three analyses, there was no compelling evidence that men with pregnant or postpartum partners had additional concurrent partnerships. Our findings suggest that even though women’s sexual activity likely declines during pregnancy and postpartum, they may not be at increased risk of HIV/STI due to their partners seeking additional partnerships.

Background: Pre-exposure prophylaxis (PrEP) is highly efficacious for preventing HIV but has not yet been brought to scale among at-risk persons. In several clinical trials in urban areas, technology-based interventions have shown a positive impact on PrEP adherence. In rural and small-town areas in the United States, which often do not have geographically proximal access to PrEP providers, additional support may be needed. This may be particularly true for younger persons who are more likely to face multiple barriers to accessing PrEP services. Home-based care, accomplished through a tailored mobile phone app, specimen self-collection (SSC), and interactive video consultations, could increase both PrEP initiation and persistence in care. Objective: The goal of this study is to assess the initiation and persistence in PrEP care for those randomized to a home-care intervention (electronic PrEP, ePrEP) relative to those assigned to the standard of care (control) condition. We will conduct additional assessments, including quantitative and qualitative analyses, to contextualize trial results and facilitate scale-up. Methods: This 2-arm, randomized controlled trial will enroll young men who have sex with men (YMSM) aged between 18 and 24 years from rural areas of Georgia, Mississippi, and North Carolina. The trial will seek to recruit a diverse sample, targeting 50% participation among highly impacted groups of black or Latino men who have sex with men. Intervention participants will receive a study app that incorporates a messaging platform, a scheduling and milestone-based tracking system for PrEP care progress, electronic behavioral surveys, and interactive video consultations with a clinician. Complemented by SSC kits mailed to laboratories for standard PrEP-related monitoring, the ePrEP system will allow participants to access PrEP care without leaving their homes. YMSM randomized to the control condition will receive a listing of nearest local PrEP providers to receive standard PrEP care. Both groups will complete quarterly electronic surveys. The primary outcome, assessed at 6 and 12 months after randomization, will be the difference in the proportion of intervention versus control participants that achieve protective levels of the active metabolite of oral PrEP (tenofovir diphosphate in dried blood spots). Results: Enrollment will begin in May 2019, with study completion in 2022. Conclusions: This trial will determine whether home PrEP care provided through an app-based platform is an efficacious means of expanding access to PrEP care for a diverse group of YMSM in rural and small-town areas of the United States.

Delay discounting is a measure of impulsivity that has been found to be associated with numerous health-related outcomes. To the extent that delay discounting is associated with sexual risk-taking, it might serve as a marker for HIV risk or as the basis for novel HIV prevention interventions. The goal of the current study was to examine the association between monetary and sexual delay discounting and condomless anal intercourse (CAI) in a cross-sectional sample of men who have sex with men. Based on previous findings, we examined whether these associations were age-dependent. Sexual, but not monetary, delay discounting was found to be associated with CAI in the past 12 months. These results suggest that delay discounting is associated with sexual risk-taking. More high risk sexual behaviors and their associations with delay discounting should be investigated in the future.

Objectives: Risk compensation (RC) could reduce or offset the biological prevention benefits of HIV pre-exposure prophylaxis (PrEP) among those at substantial risk of infection, including men who have sex with men (MSM). We investigated the potential extent and causal mechanisms through which RC could impact HIV transmission at the population and individual levels. Methods: Using a stochastic network-based mathematical model of HIV transmission dynamics among MSM in the United States, we simulated RC as a reduction in the probability of condom use after initiating PrEP, with heterogeneity by PrEP adherence profiles and partnership type in which RC occurred. Outcomes were changes to population-level HIV incidence and individual-level acquisition risk. Results: When RC was limited to MSM highly/moderately adherent to PrEP, 100% RC (full replacement of condoms) resulted in a 2% relative decline in incidence compared to no RC, but an 8% relative increase in infection risk for MSM on PrEP. This resulted from confounding by indication: RC increased the number of MSM indicated for PrEP as a function of more condomless anal intercourse among men otherwise not indicated for PrEP; this led to an increased PrEP uptake and subsequent decline in incidence. Conclusions: RC is unlikely to decrease the prevention impact of PrEP, and in some cases RC may be counterintuitively beneficial at the population level. This depended on PrEP uptake scaling with behavioral indications. Due to the increased acquisition risk associated with RC, however, clinicians should continue to support PrEP as a supplement rather than replacement of condoms.

Copyright © 2020 by the American Academy of Pediatrics. BACKGROUND:Mandatory vaccination has been effective in maintaining high vaccination coverage in countries such as the United States. However, there are no peer-reviewed analyses of the association between mandates and both coverage and subsequent incidence of vaccinepreventable disease in Europe. METHODS: Using data from the European Centre for Disease Prevention and Control and the World Health Organization, we evaluated the relationship between country-level mandatory vaccination policies and (1) measles and pertussis vaccine coverage and (2) the annual incidence of these diseases in 29 European countries. Multivariate negative binomial and linear regression models were used to quantify these associations. RESULTS: Mandatory vaccination was associated with a 3.71 (95% confidence interval [CI]: 1.68 to 5.74) percentage point higher prevalence of measles vaccination and a 2.14 (95% CI: 0.13 to 4.15) percentage point higher prevalence of pertussis vaccination when compared with countries that did not have mandatory vaccination. Mandatory vaccination was only associated with decreased measles incidence for countries without nonmedical exemptions (adjusted incidence rate ratio = 0.14; 95% CI: 0.05 to 0.36). We did not find a significant association between mandatory vaccination and pertussis incidence. CONCLUSIONS: Mandatory vaccination and the magnitude of fines were associated with higher vaccination coverage. Moreover, mandatory vaccination was associated with lower measles incidence for countries with mandatory vaccination without nonmedical exemptions. These findings can inform legislative policies aimed at increasing vaccination coverage.

Annual HIV testing is recommended for high-risk populations in the United States, to identify HIV infections early and provide timely linkage to treatment. However, heterosexuals at high risk for HIV, due to their residence in urban areas of high poverty and elevated HIV prevalence, test for HIV less frequently than other risk groups, and late diagnosis of HIV is common. Yet the factors impeding HIV testing in this group, which is predominantly African American/Black and Latino/Hispanic, are poorly understood. The present study addresses this gap. Using a systematic community-based sampling method, venue-based sampling (VBS), we estimate rates of lifetime and recent (past year) HIV testing among high-risk heterosexuals (HRH), and explore a set of putative multi-level barriers to and facilitators of recent testing, by gender. Participants were 338 HRH African American/Black and Latino/Hispanic adults recruited using VBS, who completed a computerized structured assessment battery guided by the Theory of Triadic Influence, comprised of reliable/valid measures on socio-demographic characteristics, HIV testing history, and multi-level barriers to HIV testing. Logistic regression analysis was used to identify factors associated with HIV testing within the past year. Most HRH had tested at least once (94%), and more than half had tested within the past year (58%), but only 37% tested annually. In both men and women, the odds of recent testing were similar and associated with structural factors (better access to testing) and sexually transmitted infection (STI) testing and diagnosis. Thus VBS identified serious gaps in rates of annual HIV testing among HRH. Improvements in access to high-quality HIV testing and leveraging of STI testing are needed to increase the proportion of HRH testing annually for HIV. Such improvements could increase early detection of HIV, improve the long-term health of individuals, and reduce HIV transmission by increasing rates of viral suppression.

Background: Delay discounting has been found to be associated with numerous health-related outcomes, including risky sexual behaviour. To date, it is unclear whether delay discounting measured in different domains is associated within individuals. The goal of this study was to assess the concordance of monetary and sexual delay discounting in men who have sex with men. Methods: Participants completed an online survey, including the Monetary Choice Questionnaire and the Sexual Discounting Task. Linear regression models were used to assess the association between monetary and sexual discount rates. Results: Sexual discount rates did not predict monetary discount rates. There was a substantial amount of clustering of sexual discount rates, requiring sexual discounting data to be categorised. Conclusions: Monetary and sexual delay discounting are distinct processes that are not necessarily associated within individuals, and monetary delay discounting is not an appropriate proxy measure for sexual impulsivity. Data from the Sexual Discounting Task are typically rank-transformed for analysis. These data suggest that this might be an invalid method of analysis. Future studies should investigate the distribution of their data to determine if it is appropriate to analyse sexual discounting data as a continuous measure.