WaSH insecurity and anxiety among people who inject drugs in the Tijuana-San Diego border region.

BACKGROUND: Water, sanitation, and hygiene (WaSH) insecurity increases the risk of water-related diseases. However, limited research has been conducted on psychosocial distress as it relates to WaSH insecurity, especially among people who inject drugs (PWID). We examined the relationship between WaSH insecurity and related anxiety among PWID living in different housing conditions along the US-Mexico border region. METHODS: From 2020-2021, a cross-sectional study was conducted among 585 people who injected drugs within the last month in Tijuana (N = 202), San Diego (N = 182), and in both Tijuana and San Diego (N = 201). Participants underwent interviewer-administered surveys related to WaSH access, substance use, and generalized anxiety disorder (GAD-7). Quasi-Poisson regressions were used to assess associations between WaSH insecurity and anxiety in the prior 6-months. RESULTS: Participants were 75% male, 42% were unhoused and 91% experienced WaSH insecurity in the prior 6-months. After adjusting for housing status, gender, and age, lack of access to basic drinking water (Adj RR: 1.28; 95% CI: 1.02-1.58), sanitation (Adj RR:1.28; 95% CI: 1.07-1.55), and a daily bath/shower (Adj RR: 1.38; 95% CI: 1.15-1.66) were associated with mild-severe anxiety. The number of WaSH insecurities was independently associated with a 20% increased risk of experiencing anxiety per every additional insecurity experienced (Adj RR: 1.20; CI: 1.12-1.27). We also found a significant interaction between gender and housing status (p = 0.003), indicating that among people experiencing sheltered/unsheltered homelessness, women had a higher risk of mild-severe anxiety compared to men (Adj RR: 1.55; 95% CI: 1.27-1.89). At the same time, among women, those who are unhoused have 37% increased risk of anxiety than those who live in stable housing conditions (Adj RR: 1.37; 95% CI: 1.01-1.89). CONCLUSION: The lack of specific WaSH services, particularly lack of drinking water, toilets, and daily showers were associated with higher levels of anxiety among PWID in the Tijuana-San Diego border region. Women experiencing homelessness were especially vulnerable. WaSH interventions that provide safe, 24-h access may help to reduce anxiety and health risks associated with WaSH insecurity.

Is It the Timing? Short-Term Mobility and Coital Frequency in Agbogbloshie, Ghana.

Short-term mobility is often associated with increased sexual risk behavior. Mobile individuals often have higher rates of sexual risk behavior compared to non-mobile individuals, but the reasons why are not clear. Using monthly retrospective panel data from 202 men and 282 women in Agbogbloshie, Ghana, we tested whether short-term mobility was associated with changes in coital frequency, and whether the association was due to the act of travel in the given month (e.g., enabling higher risk behavior), the reason for travel, or an individual's travel propensity at other times in the year. Overnight travel specifically to visit family or friends, or for education, health, or other reasons, was associated with increased coital frequency for men. However, men with higher travel propensities had lower overall coital frequency and the act of traveling enabled more sex only for the most frequent male travelers. Men who seldom traveled had much higher coital frequency, but the act of traveling was not associated with additional sex acts. For women, travel for education, health, or other reasons increased coital frequency. Occasional female travelers had slightly more sex acts compared to non-mobile women, and the act of traveling for these women was associated with slight increases in coital frequency, supporting the enabling hypothesis. Highly mobile women had fewer sex acts per month on average. Our findings suggest that mobility characteristics measured on a broad temporal scale, as well as the reason for mobility, are important to understand the relationship between short-term mobility and sexual behavior.

Geographic Mobility, Place Attachment, and the Changing Geography of Sex among African American and Latinx MSM Who Use Substances in Los Angeles.

The places that people go and interact with others, along with the characteristics of those places, determine degrees of sexual health risk and concomitant prevention opportunities for gay, bisexual, and other men who have sex with men (MSM). The objective of this paper is to use syndemic theory to guide analyses of 20 in-depth interviews with African American and Hispanic/Latinx MSM living in Los Angeles. We describe the places in which African American and Latinx MSM interviewees live and socialize, and how these places influence sexual behavior, drug use, and access to health care. We find common spatial patterns in mobility, incongruence in residential and sexual places, and differing geographic patterns of sex by men who use geo-social hook-up apps. Significant instability in home life and varying forms of mobility and risk-taking were a response to cumulative disadvantage and intersecting structural forces including poverty, racism, and homophobia. Our results strongly suggest that geographic mobility is a syndemic factor for HIV risk among MSM in Los Angeles, as mobility amplified negative impacts of other syndemic factors. Innovative place-interventions to reduce HIV incidence and disparities in HIV need to acknowledge the synergistic factors that drive higher HIV incidence among AA and Latinx MSM.

Coital Frequency and Male Concurrent Partnerships During Pregnancy and Postpartum in Agbogbloshie, Ghana.

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.

Effectiveness of combination packages for HIV-1 prevention in sub-Saharan Africa depends on partnership network structure: a mathematical modelling study.

OBJECTIVES: Combination packages for HIV prevention can leverage the effectiveness of biomedical and behavioural elements to lower disease incidence with realistic targets for individual and population risk reduction. We investigated how sexual network structures can maximise the effectiveness of a package targeting sexually active adults in sub-Saharan Africa (SSA) with intervention components for medical male circumcision (MMC) and sexual partnership concurrency (having >1 ongoing partner). METHODS: Network-based mathematical models of HIV type 1 (HIV-1) transmission dynamics among heterosexual couples were used to explore how changes to MMC alone and in combination with changes to concurrency impacted endemic HIV-1 prevalence and incidence. Starting from a base model parameterised from empirical data from West Africa, we simulated the prevalence of circumcision from 10% to 90% and concurrency was modelled at four discrete levels corresponding to values observed across SSA. RESULTS: MMC and concurrency could contribute to the empirical variation in HIV-1 disease prevalence across SSA. Small reductions in concurrency resulted in large declines in HIV-1 prevalence. Scaling up circumcision in low-concurrency settings yields a greater relative benefit, but the absolute number of infections averted depends on both the circumcision coverage and baseline incidence. Epidemic extinction with this package will require substantial scale-up of MMC in low-concurrency settings. CONCLUSIONS: Dynamic sexual network structure should be considered in the design and targeting of MMC within combination HIV-1 prevention packages. Realistic levels of coverage for these packages within southern Africa could lead to a reduction of incidence to the low levels observed in western Africa, and possibly, epidemic extinction.

Time From HIV Diagnosis to Viral Load Suppression: 2007-2013.

BACKGROUND: US guidelines now recommend that all HIV-infected persons receive antiretroviral therapy). HIV prevention is increasingly focused on ensuring that infected persons are diagnosed soon after HIV acquisition and quickly link to care and initiate antiretroviral therapy. We examined trends in time from HIV diagnosis to viral load suppression in King County, WA, to gauge improvement in our HIV care continuum over time. METHODS: We used HIV surveillance data and Cox proportional hazards to evaluate how the time from diagnosis to viral suppression changed among persons newly diagnosed as having HIV in King County, WA, between 2007 and 2013. RESULTS: A total of 1490 (84%) of 1766 newly diagnosed persons achieved viral suppression in a median time of 213 days (95% confidence interval, 203-229). Thirty-six percent of all persons diagnosed in 2007 and 77% in 2013 were virally suppressed within 12 months of HIV diagnosis (P < 0.0001). Differences in time to suppression by calendar year persisted when stratifying by CD4 count at diagnosis. Race was not significantly associated with time to viral suppression. CONCLUSIONS: Time from HIV diagnosis to viral suppression dramatically declined between 2007 and 2013, and more than three quarters of recently HIV-diagnosed individuals in King County, WA, now achieve viral suppression within a year of diagnosis. This improvement was evident among all persons newly diagnosed as having HIV, regardless of race/ethnicity or CD4 count at time of diagnosis.

Self-reported sex partner dates for use in measuring concurrent sexual partnerships: correspondence between two assessment methods.

Although prevalence of concurrent sexual partnerships is increasingly investigated as a driver of HIV epidemics, its measurement varies and its role in transmission dynamics remains contested. Relying on different methods of obtaining self-reported partnership histories may lead to significant differences in prevalence. This study examined the reliability of two methods for assessing dates of sex and the implications for measuring concurrent sexual partnerships. We conducted a cross-sectional reliability study using self-reported survey data from 650 women ages 18-65 years, recruited online nationwide for human papillomavirus natural history studies from 2007 to 2012. Intermethod reliability of first and last sex with the most recent partner was assessed using weighted kappa. Intraclass correlation coefficient was estimated for intramethod reliability across two consecutive questionnaires administered 4 months apart. Point prevalence of concurrent sexual partnerships at 6 months prior to the questionnaire date was similar between the two question formats (10.5 % for categorical and 10.9 % for continuous). The range between the minimum and maximum cumulative prevalence for 12 months was larger when using the categorical questions (17.0-29.6 % compared to 27.6-28.6 % using the continuous questions). Agreement between the two question formats was moderate for the date of first sex with the most recent partner (κ = 0.56, 95 % CI 0.48-0.64) and almost perfect for the date of last sex (κ = 0.93, 95 % CI 0.91-0.94). Longitudinal agreement for date of first sex was high for the continuous date question (ICC = 0.89, 95 % CI 0.86-0.92). Results of this reliability study can be used to inform the design of future studies of concurrent sexual partnerships and their association with HIV.

Replacing clinic-based tests with home-use tests may increase HIV prevalence among Seattle men who have sex with men: evidence from a mathematical model.

BACKGROUND: Home-use tests have potential to increase HIV testing but may increase the rate of false-negative tests and decrease linkage to HIV care. We sought to estimate the impact of replacing clinic-based testing with home-use tests on HIV prevalence among men who have sex with men (MSM) in Seattle, Washington. METHODS: We adapted a deterministic, continuous-time model of HIV transmission dynamics parameterized using a 2003 random digit dial study of Seattle MSM. Test performance was based on the OraQuick In-Home HIV Test (OraSure Technologies, Inc, Bethlehem, PA) for home-use tests and, on an average, of antigen-antibody combination assays and nucleic acid amplification tests for clinic-based testing. RESULTS: Based on observed levels of clinic-based testing, our baseline model predicted an equilibrium HIV prevalence of 18.6%. If all men replaced clinic-based testing with home-use tests, prevalence increased to 27.5% if home-use testing did not impact testing frequency and to 22.4% if home-use testing increased testing frequency 3-fold. Regardless of how much home-use testing increased testing frequency, any replacement of clinic-based testing with home-use testing increased prevalence. These increases in HIV prevalence were mostly caused by the relatively long window period of the currently approved test. If the window period of a home-use test were 2 months instead of 3 months, prevalence would decrease if all MSM replaced clinic-based testing with home-use tests and tested more than 2.6 times more frequently. CONCLUSIONS: Our model suggests that if home-use HIV tests replace supplement clinic-based testing, HIV prevalence may increase among Seattle MSM, even if home-use tests result in increased testing.

Place and sexual partnership transition among young American Indian and Alaska native women.

Multiple challenges expose American Indian and Alaska Native (AIAN) women to high-risk sexual partnerships and increased risk for HIV/STI. Using a unique sample of sexually-active young AIAN women (n = 129), we examined characteristics of last three partners and whether transitional partnerships were associated with different risk profiles, including where partners met, lived, and had sex. Respondents were more likely to have met their previous or current secondary partner (P2) at a friend's or family setting (versus work or social setting) (AOR = 3.92; 95 % CI 1.31, 11.70). Condom use was less likely when meeting a partner at friend's or family settings (AOR = 0.17; 95 % CI 0.05, 0.59). Sexual intercourse with P2 (compared to P1) usually took place in "riskier" settings such as a car, bar, or outside (AOR = 4.15; 95 % CI 1.59, 10.68). Perceived "safe" places, e.g., friend's or family's house, were identified with risky behaviors; thus, homogeneous messaging campaigns may promote a false sense of safety.

Conceptual framework and research methods for migration and HIV transmission dynamics.

Migration and mobility have had a profound influence on the global HIV epidemic. We propose a network-dyadic conceptual model to interpret previous literature and inform the development of future research with respect to study design, measurement methods, and analytic approach. In this model, HIV transmission is driven by risk behaviors of migrants that emerges and is enabled by mobility, the bridging of sub-epidemics across space and time, and the displacement effects on the primary residential sending community for migrants. To investigate these causal pathways, empirical study designs must measure the relative timing of migratory events, sexual risk behaviors, and incident HIV infections. Network-based mathematical models using empirical data on partnerships help gain insight into the dynamic disease transmission systems. Although the network-dyadic conceptual model and related network methods may not address all questions related to migration and HIV, they provide a unified approach for future research on this important topic.

Migration, sexual networks, and HIV in Agbogbloshie, Ghana.

BACKGROUND: HIV is spread through structured sexual networks, which are influenced by migration patterns, but network-oriented studies of mobility and HIV risk behavior have been limited. OBJECTIVE: We present a comprehensive description and initial results from our Migration & HIV in Ghana (MHG) study in Agbogbloshie, an urban slum area within Accra, Ghana. METHODS: The MHG study was a population-based cross-sectional study of adults aged 18-49 in Agbogbloshie in 2012. We used a one-year retrospective relationship history calendar to collect egocentric network data on sexual partners as well as migration and short-term mobility, and tested for prevalent HIV-1/2 infection. RESULTS: HIV prevalence was 5.5%, with prevalence among women (7.2%) over twice that of men (2.8%). Three-quarters of residents were born outside the Greater Accra region, but had lived in Agbogbloshie an average of 10.7 years. Only 7% had moved housing structures within the past year. However, short-term mobility was common. Residents had an average of 7.3 overnight trips in the last year, with women reporting more travel than men. Thirty-seven percent of men and 9% of women reported more than one sexual partner in the last year. CONCLUSIONS: Population-based surveys of migration and sexual risk behavior using relationship history calendars in low-resource settings can produce high quality data. Residents in Agbogbloshie are disproportionately affected by HIV, and have high levels of short-term mobility. HIV prevention interventions targeted to highly mobile populations in high prevalence settings may have far-reaching and long-term implications.

Seroadaptation among men who have sex with men: emerging research themes.

Seroadaptation describes a diverse set of potentially harm-reducing behaviors that use HIV status to inform sexual decision making. Men who have sex with men (MSM) in many settings adopt these practices, but their effectiveness at preventing HIV transmission is debated. Past modeling studies have demonstrated that serosorting is only effective at preventing HIV transmission when most men accurately know their HIV status, but additional modeling is needed to address the effectiveness of broader seroadaptive behaviors. The types of information withwhichMSMmake seroadaptive decisions is expanding to include viral load, treatment status, and HIV status based on home-use tests, and recent research has begun to examine the entire seroadaptive process, from an individual's intentions to seroadapt to their behaviors to their risk of acquiring or transmitting HIV and other STIs. More research is needed to craft clear public health messages about the risks and benefits of seroadaptive practices.

Geographic mobility and its impact on sexual health and ongoing HIV transmission among migrant latinx men who have sex with men.

An understudied social process that may determine variable HIV risk, testing, and linkage to care is geographic mobility, including immigration as well as short-term mobility, especially among sexual minority populations. We aimed to assess how geographic mobility over the lifecourse between Latin America and the U.S., and within the U.S., was linked to sexual risk and health behaviors among Latinx migrant men who have sex with men (MSM) in San Bernardino County, California. Qualitative analysis of 16 semi-structured interviews revealed four major domains of influence on participants' sexual risk behaviors. At the micro level, these included social environment/interpersonal factors (e.g., family and peer support) and geographic factors and pathways (e.g., migration journey to the U.S.). At the macro level data centered on cultural factors (e.g., gender norms in home country) and structural factors (e.g., HIV healthcare). Our results can illuminate and promote effective health policies and HIV reduction efforts for Latinx migrant MSM in metro areas.

Novel Location-Based Survey Using Cognitive Interviews to Assess Geographic Networks and Hotspots of Sex and Drug Use: Implementation and Validation Study.

BACKGROUND: The Ending the HIV Epidemic initiative in the United States relies on HIV hotspots to identify where to geographically target new resources, expertise, and technology. However, interventions targeted at places with high HIV transmission and infection risk, not just places with high HIV incidence, may be more effective at reducing HIV incidence and achieving health equity. OBJECTIVE: We described the implementation and validation of a web-based activity space survey on HIV risk behaviors. The survey was intended to collect geographic information that will be used to map risk behavior hotspots as well as the geography of sexual networks in Los Angeles County. METHODS: The survey design team developed a series of geospatial questions that follow a 3-level structure that becomes more geographically precise as participants move through the levels. The survey was validated through 9 cognitive interviews and iteratively updated based on participant feedback until the saturation of topics and technical issues was reached. RESULTS: In total, 4 themes were identified through the cognitive interviews: functionality of geospatial questions, representation and accessibility, privacy, and length and understanding of the survey. The ease of use for the geospatial questions was critical as many participants were not familiar with mapping software. The inclusion of well-known places, landmarks, and road networks was critical for ease of use. The addition of a Google Maps interface, which was familiar to many participants, aided in collecting accurate and precise location information. The geospatial questions increased the length of the survey and warranted the inclusion of features to simplify it and speed it up. Using nicknames to refer to previously entered geographic locations limited the number of geospatial questions that appeared in the survey and reduced the time taken to complete it. The long-standing relationship between participants and the research team improved comfort to disclose sensitive geographic information related to drug use and sex. Participants in the cognitive interviews highlighted how trust and inclusive and validating language in the survey alleviated concerns related to privacy and representation. CONCLUSIONS: This study provides promising results regarding the feasibility of using a web-based mapping survey to collect sensitive location information relevant to ending the HIV epidemic. Data collection at several geographic levels will allow for insights into spatial recall of behaviors as well as future sensitivity analysis of the spatial scale of hotspots and network characteristics. This design also promotes the privacy and comfort of participants who provide location information for sensitive topics. Key considerations for implementing this type of survey include trust from participants, community partners, or research teams to overcome concerns related to privacy and comfort. The implementation of similar surveys should consider local characteristics and knowledge when crafting the geospatial components.

Concurrent partnerships, acute infection and HIV epidemic dynamics among young adults in Zimbabwe.

This paper explores the roles of acute infection and concurrent partnerships in HIV transmission dynamics among young adults in Zimbabwe using realistic representations of the partnership network and all published estimates of stage-specific infectivity. We use dynamic exponential random graph models to estimate partnership network parameters from an empirical study of sexual behavior and drive a stochastic simulation of HIV transmission through this dynamic network. Our simulated networks match observed frequencies and durations of short- and long-term partnerships, with concurrency patterns specific to gender and partnership type. Our findings suggest that, at current behavior levels, the epidemic cannot be sustained in this population without both concurrency and acute infection; removing either brings transmission below the threshold for persistence. With both present, we estimate 20-25% of transmissions stem from acute-stage infections, 30-50% from chronic-stage, and 30-45% from AIDS-stage. The impact of acute infection is strongly moderated by concurrency. Reducing this impact by reducing concurrency could potentially end the current HIV epidemic in Zimbabwe.

Change in sexual activity 12 months after ART initiation among HIV-positive Mozambicans.

We assessed sexual behaviors before and 12-months after ART initiation among 277 Mozambicans attending an HIV clinic. Measured behaviors included the number of sexual partners, condom use, concurrent relationships, disclosure of HIV status, alcohol use, and partners' serostatus. Compared to before ART initiation, increases were seen 12 months after ART in the proportion of participants who were sexually active (48% vs. 64% respondents, P < 0.001) and the proportion of participants with HIV-negative or unknown serostatus partners (45% vs. 80%, P < 0.001). Almost all (96%) concurrent partnerships reported at 12 months formed after ART initiation. Although reported correct and consist condom use increased, the number of unprotected sexual relationships remained the same (n = 45). Non-disclosure of HIV-serostatus to sexual partners was the only significant predictor of practicing unprotected sex with partners of HIV-negative or unknown serostatus. Sexual activity among HIV-positive persons on ART increased 12 months after ART initiation. Ongoing secondary transmission prevention programs addressing sexual activity with multiple partners, disclosure to partners and consistent condom use with serodisconcordant partners must be incorporated throughout HIV care programs.

A call for epidemic modeling to examine historical and structural drivers of racial disparities in infectious disease.

Since this is a commentary, there is no abstract.

Effective strategies to promote HIV self-testing for men who have sex with men: Evidence from a mathematical model.

BACKGROUND: HIV testing is the gateway to HIV treatment and prevention. HIV self-testing (HIVST) has potential to increase testing; however, the potential population-level impact of HIVST on the HIV epidemic and the best strategies for promoting HIVST are unknown. Our aim is to inform public health approaches for promoting HIVST as part of a comprehensive strategy to reduce HIV incidence. METHODS: Stochastic network-based HIV transmission models were used to estimate how different HIVST strategies would affect HIV incidence in Seattle and Atlanta over 10 years. We included four types of HIV testers and implemented nine replacement and eleven supplementation strategies for HIVST. RESULTS: Replacement of clinic-based tests with HIVST increased HIV incidence in Seattle and Atlanta. The benefits of supplementary strategies depended on the tester type using HIVST. Targeting non-testers averted the highest number of cases per test. In Seattle 2.2 (95%SI=-77, 100.4) and 4.7 (95%SI=-35.7, 60.1) infections were averted per 1000 HIVST when non-testers used HIVST once or twice per year respectively. In Atlanta the comparable rates were 8.0 (95%SI=-60.3 to 77.7) and 6.7 (95%SI=-37.7, 41.0). Paradoxically, increasing testing among risk-based testers using HIVST increased incidence. CONCLUSIONS: The population-level impact of HIVST depends on who is reached with HIVST, how kits are used, and by characteristics of the underlying epidemic and HIV care infrastructure. Targeted HIVST can be an effective component of a comprehensive HIV testing strategy. More work is needed to understand how to identify and target non-testers for self-testing implementation.

Sexual partner concurrency and sexual risk among gay, lesbian, bisexual, and transgender American Indian/Alaska natives.

BACKGROUND: American Indian and Alaska Natives suffer pervasive health disparities, including disproportionately high rates of HIV. Sexual network dynamics, including concurrency and sexual mixing patterns, are key determinants of HIV disparities. METHODS: We analyzed data from the first national study of gay, lesbian, bisexual, and transgender American Indian and Alaska Natives to examine the prevalence of concurrency, sex and race of partners, and level of risk across different partnership patterns. Egocentric network data were analyzed at the level of the respondents, who were grouped according to the sex of their last 3 partners. RESULTS: Overall rates of HIV and concurrency were high in this population. HIV prevalence (34%) and cumulative prevalence of concurrency (55%) were highest among men who had sex with only men, while women who had sex with only women reported lower concurrency and HIV. Women who had sex with women and men also had high HIV prevalence (15%) and reported slightly higher concurrency risk and low condom use, making them effective bridge populations. CONCLUSIONS: The uniformly high rates of Native partner selection creates the potential for amplification of disease spread within this small community, while the high rates of selecting partners of other races creates the potential for bridging to other groups in the transmission network. These findings provide some of the first insights into sexual networks and concurrency among Native gay, lesbian, bisexual, and transgender populations and suggest that both men and women deserve attention in HIV prevention efforts at individual, dyadic and population levels.

Immigrant Generational Differences in Social Support and Sexual Risk Behaviors Among Men Who Have Sex With Men in Seattle, Washington.

Different immigrant generations may encounter distinct sexual opportunities with implications for HIV transmission. Yet, few studies have examined how immigrant generational status is associated with sexual risk behaviors among men who have sex with men (MSM). We explored relationships between immigrant generational status, social support, and sexual risk behaviors among English-speaking MSM using data from surveys conducted in Seattle, Washington, in 2014 (n = 323). We compared the sexual risk behaviors and social support of first-generation, second-generation, and third- and higher-generation MSM, and examined whether immigrant generational status and social support were associated with sexual risk behaviors using logistic regression models. Second-generation MSM reported lower friend social support than first- or third- and higher-generation MSM (p < .05). However, immigrant generational status was not associated with sexual risk behavior outcomes, even after accounting for social support. Results suggest that differences in immigration processes such as acculturation may be more predictive of risk behaviors than generational status alone.