Discovering dominant tumor immune archetypes in a pan-cancer census.

Cancers display significant heterogeneity with respect to tissue of origin, driver mutations, and other features of the surrounding tissue. It is likely that individual tumors engage common patterns of the immune system-here "archetypes"-creating prototypical non-destructive tumor immune microenvironments (TMEs) and modulating tumor-targeting. To discover the dominant immune system archetypes, the University of California, San Francisco (UCSF) Immunoprofiler Initiative (IPI) processed 364 individual tumors across 12 cancer types using standardized protocols. Computational clustering of flow cytometry and transcriptomic data obtained from cell sub-compartments uncovered dominant patterns of immune composition across cancers. These archetypes were profound insofar as they also differentiated tumors based upon unique immune and tumor gene-expression patterns. They also partitioned well-established classifications of tumor biology. The IPI resource provides a template for understanding cancer immunity as a collection of dominant patterns of immune organization and provides a rational path forward to learn how to modulate these to improve therapy.

Silicon Valley Meets Biomedical Research in the Chan Zuckerberg Initiative.

The Chan Zuckerberg Initiative, the philanthropy launched by Facebook CEO Mark Zuckerberg and his wife Priscilla Chan, drew attention with its stated goal of helping to "cure, manage, or treat all diseases" by the end of the century. They intend to do it through funding basic research and addressing gaps in biomedical technology.

Transoceanic pathogen transfer in the age of sail and steam.

In the centuries following Christopher Columbus's 1492 voyage to the Americas, transoceanic travel opened unprecedented pathways in global pathogen circulation. Yet no biological transfer is a single, discrete event. We use mathematical modeling to quantify historical risk of shipborne pathogen introduction, exploring the respective contributions of journey time, ship size, population susceptibility, transmission intensity, density dependence, and pathogen biology. We contextualize our results using port arrivals data from San Francisco, 1850 to 1852, and from a selection of historically significant voyages, 1492 to 1918. We offer numerical estimates of introduction risk across historically realistic ranges of journey time and ship population size, and show that both steam travel and shipping regimes that involved frequent, large-scale movement of people substantially increased risk of transoceanic pathogen circulation.

Ancient and modern genomics of the Ohlone Indigenous population of California.

SignificanceCalifornia supports a high cultural and linguistic diversity of Indigenous peoples. In a partnership of researchers with the Muwekma Ohlone tribe, we studied genomes of eight present-day tribal members and 12 ancient individuals from two archaeological sites in the San Francisco Bay Area, spanning ∼2,000 y. We find that compared to genomes of Indigenous individuals from throughout the Americas, the 12 ancient individuals are most genetically similar to ancient individuals from Southern California, and that despite spanning a large time period, they share distinctive ancestry. This ancestry is also shared with present-day tribal members, providing evidence of genetic continuity between past and present Indigenous individuals in the region, in contrast to some popular reconstructions based on archaeological and linguistic information.

Geographical patterns of social cohesion drive disparities in early COVID infection hazard.

The uneven spread of COVID-19 has resulted in disparate experiences for marginalized populations in urban centers. Using computational models, we examine the effects of local cohesion on COVID-19 spread in social contact networks for the city of San Francisco, finding that more early COVID-19 infections occur in areas with strong local cohesion. This spatially correlated process tends to affect Black and Hispanic communities more than their non-Hispanic White counterparts. Local social cohesion thus acts as a potential source of hidden risk for COVID-19 infection.

Antigenic Characterization of Novel Human Norovirus GII.4 Variants San Francisco 2017 and Hong Kong 2019.

Norovirus is a major cause of acute gastroenteritis; GII.4 is the predominant strain in humans. Recently, 2 new GII.4 variants, Hong Kong 2019 and San Francisco 2017, were reported. Characterization using GII.4 monoclonal antibodies and serum demonstrated different antigenic profiles for the new variants compared with historical variants.

Evaluating a Targeted Minimum Loss-Based Estimator for Capture-Recapture Analysis: An Application to HIV Surveillance in San Francisco, California.

The capture-recapture method is a common tool used in epidemiology to estimate the size of "hidden" populations and correct the underascertainment of cases, based on incomplete and overlapping lists of the target population. Log-linear models are often used to estimate the population size yet may produce implausible and unreliable estimates due to model misspecification and small cell sizes. A novel targeted minimum loss-based estimation (TMLE) model developed for capture-recapture makes several notable improvements to conventional modeling: "targeting" the parameter of interest, flexibly fitting the data to alternative functional forms, and limiting bias from small cell sizes. Using simulations and empirical data from the San Francisco, California, Department of Public Health's human immunodeficiency virus (HIV) surveillance registry, we evaluated the performance of the TMLE model and compared results with those of other common models. Based on 2,584 people observed on 3 lists reportable to the surveillance registry, the TMLE model estimated the number of San Francisco residents living with HIV as of December 31, 2019, to be 13,523 (95% confidence interval: 12,222, 14,824). This estimate, compared with a "ground truth" of 12,507, was the most accurate and precise of all models examined. The TMLE model is a significant advancement in capture-recapture studies, leveraging modern statistical methods to improve estimation of the sizes of hidden populations.

Caring for Patients with Functional Impairment in Middle Age: Perspectives from Primary Care Providers and Geriatricians.

BACKGROUND: The prevalence of functional impairment is increasing among middle-aged adults and is associated with adverse health outcomes. Primary care providers (PCPs) and geriatricians may have important insights about optimal approaches to caring for these patients, but little is known about their perspectives. OBJECTIVE: To examine PCPs' and geriatricians' perspectives on clinical needs and optimal approaches to care for middle-aged patients with functional impairment. DESIGN: Qualitative study using semi-structured interviews. PARTICIPANTS: PCPs and geriatricians from outpatient practices in the San Francisco Bay area. APPROACH: Interviews focused on characteristics and care needs of middle-aged patients with functional impairment and models of care to address these needs. We analyzed interviews using hybrid deductive-inductive qualitative thematic analysis. KEY RESULTS: Clinicians (14 PCPs, 15 geriatricians) described distinct characteristics of functional impairment in middle-aged versus older adults, such as different rates of onset, but similar clinical needs. Despite these similar needs, clinicians identified age-specific barriers to delivering optimal care to middle-aged patients. These included system-level challenges such as limited access to insurance and social services; practice- and clinician-level barriers including inadequate clinician training; and patient-level factors including less access to family caregivers and perceptions of stigma. To overcome these challenges, clinicians suggested clinical approaches including addressing health-related social needs within healthcare systems; implementing practice-based models that are multi-disciplinary, team-based, and coordinated; training clinicians to effectively manage functional impairment; and expanding community-based services and supports to help patients navigate the medical system. Identified needs, challenges, and solutions were generally similar across geriatricians and PCPs. CONCLUSIONS: Clinicians face challenges in delivering optimal care to middle-aged patients who have functional impairments similar to their older counterparts but lack access to services and supports available to older people. These findings suggest the importance of increasing access to care models that address functional impairment regardless of age.

How Primary Care Clinicians Process Patient Death: Logistics, Emotions, and Opportunities for Structural Support.

BACKGROUND: Navigating the logistics and emotional processing of a patient's death is an inevitable part of many physicians' roles. While research has primarily examined how inpatient clinicians cope with patient loss, little work has explored how primary care clinicians (PCCs) handle patient death in the outpatient setting, and what support resources could help PCCs process loss. OBJECTIVE: To explore PCCs' experiences with the logistics and emotional processing of patient deaths and suggestions for supportive resources. DESIGN: Qualitative study using semi-structured interviews conducted between March and May 2023. PARTICIPANTS: Recruitment emails were sent to 136 PCCs (physicians and nurse practitioners) at three San Francisco academic primary care clinics. Twelve clinicians participated in the study. APPROACH: This study used a template analysis approach. Interview transcripts were analyzed in an iterative fashion to identify themes for how PCCs navigate patient death. RESULTS: Participants (n=12) described outpatient death notification as inconsistent, delayed, and rife with uncertainty regarding subsequent actions. They felt various emotions, notably sadness and guilt, especially with deaths of young, vulnerable patients or those from preventable illnesses. Participants identified strategies for emotional processing and recommended improvements including clear procedural guidance, peer debriefings, and formal acknowledgements of deceased patients. CONCLUSIONS: Interviewing PCCs about their experiences following a patient death revealed key themes in logistical and emotional processing, and clinic resource recommendations to better support PCCs. Given the distinct characteristics of primary care-such as enduring patient relationships, greater isolation in ambulatory settings compared to inpatient environments, and rising burnout rates-enhancing guidance and support for PCCs is crucial to mitigate administrative burdens and grief after patient loss.

Factors Associated with Smoking Cessation and the Receipt of Cessation Services in a Public, Safety-Net Primary Care System.

BACKGROUND: Prevalence of smoking is high among patients receiving care in safety-net settings, and there is a need to better understand patient factors associated with smoking cessation and receipt of cessation services. OBJECTIVE: To identify patient factors associated with smoking cessation attempts and receipt of cessation counseling and pharmacotherapy in a large safety-net health system. DESIGN: We conducted a retrospective cohort analysis using EHR data in a safety-net system in San Francisco, CA. PARTICIPANTS: We included 7384 adult current smokers who had at least three unique primary care encounters with documented smoking status between August 2019 and April 2022. MAIN MEASURES: We assessed four outcomes using multivariate generalized estimating equation models: (1) any cessation attempt, indicating a transition in smoking status from "current smoker" to "former smoker"; (2) sustained cessation, defined as transition in smoking status from current smoker to former smokers for two or more consecutive visits; (3) receipt of smoking cessation counseling from healthcare providers; and (4) receipt of pharmacotherapy. KEY RESULTS: Of 7384 current adult smokers, 17.6% had made any cessation attempt, and of those 66.5% had sustained cessation. Most patients (81.1%) received counseling and 41.8% received pharmacotherapy. Factors associated with lower odds of any cessation attempt included being aged 45-64, non-Hispanic black, and experiencing homelessness. The factor associated with lower odds of sustained cessation was being male. Factors associated with lower odds of receiving counseling were being insured by Medicaid or being uninsured. Factors associated with lower odds of receiving pharmacotherapy included speaking languages other than English, being male, and identifying as racial and ethnic minorities. CONCLUSIONS: Health system interventions could close the gap in access to smoking cessation services for unhoused and racial/ethnic minority patients in safety-net settings, thereby increasing cessation among these populations.

Interruptions in HIV and Behavioral Health Care for Criminal-Legal Involved People Living with HIV Following Implementation of Decarceration and Shelter in Place in San Francisco, California.

Decarceration policies, enacted for SARS-CoV-2 mitigation in carceral settings, potentially exacerbated barriers to care for people living with HIV (PWH) with criminal legal involvement (CLI) during Shelter-in-Place (SIP) by limiting opportunities for engagement in provisions of HIV and behavioral health care. We compared health care engagement for PWH with CLI in San Francisco, California before and after decarceration and SIP using interrupted time series analyses. Administrative data identified PWH booked at the San Francisco County Jail with at least one clinic encounter from 01/01/2018-03/31/2020 within the municipal health care network. Monthly proportions of HIV, substance use, psychiatric and acute care encounters before (05/01/2019-02/29/2020) and after (03/01/2020-12/31/2020) SIP and decarceration were compared using Generalized Estimating Equation (GEE) log-binomial and logistic regression models, clustering on the patient-level. Of 436 patients, mean age was 43 years (standard-deviation 11); 88% cisgender-male; 39% white, 66% homeless; 67% had trimorbidity by Elixhauser score (medical comorbidity, psychotic disorder or depression, and substance use disorder). Clinical encounters immediately dropped following SIP for HIV (aOR = 0.77; 95% CI: 0.67, 0.90) and substance use visits (aRR = 0.83; 95% CI: 0.70, 0.99) and declined in subsequent months. Differential reductions in clinical encounters were seen among Black/African Americans (aRR = 0.93; 95% CI: 0.88, 0.99) and people experiencing homelessness (aRR = 0.92; 95% CI: 0.87, 0.98). Significant reductions in care were observed for PWH with CLI during the COVID-19 pandemic, particularly among Black/African Americans and people experiencing homelessness. Strategies to End the HIV Epidemic must improve engagement across diverse care settings to improve outcomes for this key population.

Continuing Low Awareness and Use of Pre-exposure Prophylaxis (PrEP) for HIV among People Who Inject Drugs (PWID), San Francisco, 2022.

Clinical trials provide evidence that pre-exposure prophylaxis (PrEP) prevents HIV acquisition including through sharing of injection equipment among people who inject drugs (PWID). However, uptake among many populations at risk for HIV has been slow, particularly among PWID. We examined data from the National HIV Behavioral Surveillance (NHBS) from San Francisco in 2022 to measure PrEP uptake and identify factors associated with PrEP awareness among PWID. Of 479 PWID with HIV-negative or unknown HIV status, 54.9% were aware of PrEP, 5.9% had discussed PrEP with a healthcare provider, and 1.5% had used PrEP in the past year. Lack of PrEP awareness was associated with being age 50 years and older (adjusted odds ratio [aOR] 0.40, 95% CI 0.27-0.60), being men who have sex with women (vs. men who have sex with men, aOR 0.47, 95% CI 0.24-0.92), having a disability (aOR 0.58, 95% CI 0.35-0.95), using heroin as their most frequently injected drug (aOR 0.51, 95% CI, 0.34-0.78), not having tested for HIV, HCV, or an STD in the past year (aOR 0.43, 95% CI 0.28-0.64), and not having access to new sterile needles in the past year (aOR 0.28, 95%CI 0.08-1.00). We found negligible change in the awareness and uptake of PrEP among PWID since previously measured in NHBS in 2018. Low PrEP use among PWID may be addressed by increasing provider discussion of PrEP with their PWID patients and clients during routine care, expanding testing for injection-related infections among PWID, and integrating PrEP access into harm reduction programs.

Acceptability of Long-Acting Injectable Antiretroviral Therapy Among People with HIV Receiving Care at Three Ryan White Funded Clinics in the United States.

Understanding the acceptability of long-acting injectable antiretroviral therapy (LAI-ART) among people with HIV (PWH), especially priority populations, is essential for effective implementation. We conducted semi-structured interviews with patients in three Ryan White-funded HIV clinics in San Francisco, Chicago, and Atlanta. We employed maximal variation sampling across age, gender, race, ethnicity, and time living with HIV and oversampled for individuals with suboptimal clinical engagement. An 8-step hybrid deductive and inductive thematic analysis approach guided data analysis. Between August 2020 and July 2021, we conducted 72 interviews. Median age was 46 years; 28% were ciswomen, 7% transwomen, 44% Black/African-American and 35% Latinx, 43% endorsed a psychiatric diagnosis, 35% were experiencing homelessness/unstable housing, and 10% had recent substance use. Approximately 24% were sub-optimally engaged in care. We observed a spectrum of LAI-ART acceptability, ranging from enthusiasm to hesitancy to rejection. We also characterized four emergent orientations towards LAI-ART: innovator, pragmatist, deliberator, and skeptic. Overall, the majority of participants expressed favorable initial reactions towards LAI-ART. Most approached LAI-ART pragmatically, but acceptability was not static, often increasing over the course of the interview. Participants considered their HIV providers as essential for affirming personal relevance. HIV stigma, privacy concerns, and medical mistrust had varied impacts, sometimes facilitating and other times hindering personal relevance. These findings held across priority populations, specifically young adults, cis/trans women, racial/ethnic minorities, and individuals with suboptimal clinical engagement. Further research is needed to explore the transition from hypothetical acceptance to uptake and to confirm the actual benefits and drawbacks of this treatment.

RESUMEN: La aceptabilidad de la terapia antirretroviral inyectable de acción prolongada (LAI-ART, por su sigla en inglés) entre personas con VIH es esencial para una implementación efectiva. Durante el periodo de agosto de 2020 a julio de 2021, realizamos 72 entrevistas semiestructuradas con personas con VIH en clínicas públicas ubicadas en San Francisco, Chicago y Atlanta. Un análisis temático, tanto deductivo como inductivo, guio nuestra investigación. Observamos un espectro de aceptabilidad de LAI-ART que va desde el entusiasmo hasta la indecisión y el rechazo. También caracterizamos cuatro orientaciones actitudinales emergentes hacia LAI-ART: innovadora, pragmática, deliberativa y escéptica. Los participantes también señalaron la importancia de sus proveedores de VIH para validar su relevancia personal. El estigma asociado al VIH, preocupaciones sobre la privacidad y desconfianza en el sistema médico tuvieron diversos impactos, a veces facilitando y otras veces obstaculizando la relevancia personal. Entre las poblaciones prioritarias del estudio, los resultados fueron consistentes.

Disparities in HIV Testing and PrEP Awareness for Black Women who Inject Drugs in San Francisco, California.

HIV disproportionately affects Black/African Americans (AA), while PrEP is under-utilized by Black/AA, women, and people who inject drugs (PWID). In San Francisco, California's National HIV Behavioral Surveillance among PWID in 2022, Black/AA women were the least likely to be tested for HIV among all groups by sex and race/ethnicity and the least likely to be aware of PrEP among women. Yet, Black/AA women were no less likely to see a healthcare provider in the last year. Data suggest that providers' failure to discuss and address HIV risk with Black/AA female PWID is a major barrier to accessing effective care and prevention. El VIH afecta de manera desproporcionada a Black/afroamericanos (AA), mientras que la PrEP está infrautilizada por los Black/AA, las mujeres y las personas que se inyectan drogas (PWID). En la National HIV Behavioral Surveillance de PWID de San Francisco, California en 2022, las mujeres Black/AA eran las que menos probabilidades tenían de someterse a la prueba del VIH entre todos los grupos por sexo y raza/etnia y las que menos probabilidades tenían de conocer la PrEP entre las mujeres. Sin embargo, las mujeres Black/AA no tenían menos probabilidades de acudir a un profesional sanitario en el último año. Los datos sugieren que el hecho de que los proveedores no hablen ni aborden el riesgo de VIH con las PWID de raza Black/AA es un obstáculo importante para acceder a una atención y prevención eficaces.

Acceptability of an automated directly observed therapy (DOT) application for PrEP adherence support among young men who have sex with men: a qualitative exploration.

Pre-exposure prophylaxis (PrEP) adherence remains a challenge among young men who have sex with men (MSM). We developed and tested a smartphone application ("app"), "DOT Diary", which combines automated directly observed therapy (DOT) with information about PrEP protection levels, pill-taking reminders, a sexual behavior diary, and a PrEP dosing calendar. To contextualize trial results, we qualitatively explored participants' app experiences. The trial enrolled 100 young MSM in San Francisco and Atlanta. Participants were randomized 2:1 to DOT Diary versus standard-of-care and followed for 24 weeks. Interviews were conducted with 24 intervention participants. Data were analyzed using a memo-writing approach. Most expressed overall satisfaction with the app ("it was good for its purpose"), despite concerns about technical glitches. The most popular app features were the monthly calendar showing days PrEP was taken and information about level of protection based on pills taken. The DOT component helped participants establish PrEP routines. The reminders were "annoying but effective" at motivating dosing. Opinions about the sexual behavior diary varied. Overall, DOT Diary was acceptable; participants were willing to use it daily to record pill-taking. Critical components included the information about PrEP protection levels and calendar, while others may be modified to improve future success.Trial registration: ClinicalTrials.gov identifier: NCT03771638.

Environmental Justice and Systems Analysis for Air Quality Planning in the Port of Oakland in California.

Many frontline communities experience adverse health impacts from living in proximity to high-polluting industrial sources. Securing environmental justice requires, in part, a comprehensive set of quantitative indicators. We incorporate environmental justice and life-cycle thinking into air quality planning to assess fine particulate matter (PM2.5) exposure and monetized damages from operating and maintaining the Port of Oakland, a major multimodal marine port located in the historically marginalized West Oakland community in the San Francisco Bay Area. The exposure domain for the assessment is the entire San Francisco Bay Area, a home to more than 7.5 million people. Of the more than 14 sources included in the emissions inventory, emissions from large container ships, or ocean-going vessels (OGVs), dominate the PM2.5 intake, and supply chain sources (material production and delivery, fuel production) represent between 3.5% and 7.5% of annual intake. Exposure damages, which model the costs from excess mortalities resulting from exposure from the study's emission sources, range from USD 100 to 270 million per annum. Variations in damages are due to the use of different concentration-response relationships, hazard ratios, and Port resurfacing area assumptions. Racial and income-based exposure disparities are stark. The Black population and people within the lowest income quintile are 2.2 and 1.9 times more disproportionately exposed, respectively, to the Port's pollution sources relative to the general population. Mitigation efforts focused on electrifying in-port trucking operations yield modest reductions (3.5%) compared to strategies that prioritize emission reductions from OGVs and commercial harbor craft operations (8.7-55%). Our recommendations emphasize that a systems-based approach is critical for identifying all relevant emission sources and mitigation strategies for improving equity in civil infrastructure systems.

Overdose from Unintentional Fentanyl Use when Intending to Use a Non-opioid Substance: An Analysis of Medically Attended Opioid Overdose Events.

Fentanyl-mixed and substituted heroin is well-documented, but less is known about unintentional fentanyl use among people using stimulants. To determine the prevalence of and racial and ethnic disparities in unintentional fentanyl use among people experiencing a medically attended opioid overdose, we reviewed 448 suspected non-fatal overdose cases attended by a community paramedic overdose response team in San Francisco from June to September 2022. We applied a case definition for opioid overdose to paramedic records and abstracted data on intended substance use prior to overdose. Among events meeting case criteria with data on intended substance use, intentional opioid use was reported by 57.3%, 98.0% of whom intended to use fentanyl. No intentional opioid use was reported by 42.7%, with most intending to use stimulants (72.6%), including methamphetamine and cocaine. No intentional opioid use was reported by 58.5% of Black, 52.4% of Latinx, and 28.8% of White individuals (p = 0.021), and by 57.6% of women and 39.5% of men (p = 0.061). These findings suggest that unintentional fentanyl use among people without opioid tolerance may cause a significant proportion of opioid overdoses in San Francisco. While intentional fentanyl use might be underreported, the magnitude of self-reported unintentional use merits further investigation to confirm this phenomenon, explore mechanisms of use and disparities by race and ethnicity, and deploy targeted overdose prevention interventions.

Health impact assessment of PM2.5 from uncovered coal trains in the San Francisco Bay Area: Implications for global exposures.

Coal generates almost 40% of the world's electricity with 80 countries throughout the world using coal power. An inherent part of this generation is the rail transport of coal in uncovered cars, often up to a mile long. Existing studies document the subsequent increments of PM2.5 to the near-rail populations, which typically include a large number of economically disadvantaged residents and/or people of color. However, to date there is no assessment of the health implications of this stage in the use of coal. The present study quantifies such impacts on a region in the San Francisco Bay Area. The analysis shows important effects on mortality, hospitalization for cardiovascular and respiratory disease, asthma exacerbation, work loss, and days of restricted activity. Several of these outcomes exhibited a one to six percent increase over baseline. As such, it delineates the implications for the global effects of the transport of coal.

Detectable viral load associated with unmet mental health and substance use needs among trans women living with HIV in San Francisco, California.

BACKGROUND: Substance use and mental distress are known barriers to HIV care engagement among trans women. Less is known about access and utilization of mental health and substance use care among trans women and the relationship between unmet behavioral health needs and HIV viral suppression. We examined the relationship between mental health and substance use on HIV viral load among trans women living with HIV. We also examined the relationship between mental health and substance use services needs with HIV care engagement and having a detectable viral load by comparing engagement in care cascades. METHODS: Data are from a 2022 baseline assessment for an intervention with trans women living with HIV (n = 42) in San Francisco. Chi-Squared or Fisher's exact tests were conducted to determine associations between HIV viral load, mental health, and substance use. We also examine characteristics associated with each step in the HIV, mental health, and substance use care cascades. RESULTS: Most participants were trans women of color (85.7%), 40 years of age or older (80.9%), with low income (88.1%), and almost half were unstably housed (47.6%). Of the 32 participants who screened positive for depression, anxiety and/or psychological distress, 56.3% were referred for mental health services in the past 12 months. Of those who were referred, 44.4% received mental health services. Of the 26 participants who screened positive for a substance use disorder, 34.6% were referred to substance use services in the past 12 months. Of those referred, 33.3% received substance use services in the past 3 months. Latina trans women had a low referral rate to meet their mental health needs (50%) and only 16.7% of African American/Black trans women who screened positive for a substance use disorder were referred for services, while trans women of other race/ethnicities had high referral and services utilization. No significant results were found between HIV viral load and screening positive for a mental health disorder. Methamphetamine use was statistically associated with having a detectable HIV viral load (p = 0.049). CONCLUSIONS: We identified significant unmet mental health and substance use services needs and noted racial/ethnic disparities in the context of high HIV care engagement among trans women living with HIV. We also found that methamphetamine use was a barrier to having an undetectable viral load for trans women living with HIV. To finally end the HIV epidemic, integration of behavioral health screening, linkage, and support are needed in HIV care services for populations most impacted by HIV, especially trans women. TRIAL REGISTRATION: NCT, NCT 21-34,978. Registered January 19, 2022.

"They made me feel like I mattered": a qualitative study of how mobile crisis teams can support people experiencing homelessness.

BACKGROUND: Mobile crisis teams (MCTs) can be important alternatives to emergency medical services or law enforcement for low-acuity 911 calls. MCTs address crises by de-escalating non-violent situations related to mental health or substance use disorders and concurrent social needs, which are common among people experiencing homelessness (PEH). We sought to explore how an MCT in one city served the needs and supported the long- and short-term goals of PEH who had recently received MCT services. METHODS: We conducted 20 semi-structured interviews with service recipients of the Street Crisis Response Team, a new 911-dispatched MCT implemented in San Francisco in November 2020. In the weeks after their encounter, we interviewed respondents about their overall MCT experience and comparisons to similar services, including perceived facilitators and barriers to the respondent's self-defined life goals. We analyzed interview transcripts with thematic analysis to capture salient themes emerging from the text and organized within a social-ecological model. RESULTS: Nearly all respondents preferred the MCT model over traditional first responders, highlighting the team's person-centered approach. Respondents described the MCT model as effectively addressing their most immediate needs (e.g., food), short-term relief from the demands of homelessness, acute mental health or substance use symptoms, and immediate emotional support. However, systemwide resource constraints limited the ability of the team to effectively address longer-term factors that drive crises, such as solutions to inadequate quality and capacity of current housing and healthcare systems and social services navigation. CONCLUSIONS: In this study, respondents perceived this MCT model as a desirable alternative to law enforcement and other first responders while satisfying immediate survival needs. To improve MCT's effectiveness for PEH, these teams could collaborate with follow-up providers capable of linking clients to resources and services that can meet their long-term needs. However, these teams may not be able to meaningfully impact the longstanding and complex issues that precipitate crises among PEH in the absence of structural changes to upstream drivers of homelessness and fragmentation of care systems.