Low Barrier Technology Interventions

Principal Investigator: Laura Bamford 

Budget: $108,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: The overarching goal of this project is to increase retention in care in people who use drugs with HIV in San Diego Conty through low barrier technology mobile HIV primary care. Individuals who report injection drug use as their HIV transmission risk factor have the lowest rates of viral suppression of all demographic groups in San Diego. Further, individuals with HIV who use methamphetamine in San Diego have lower retention in care and HIV viral suppression rates compared to individuals with HIV who do not use methamphetamine. Traditional HIV care models that require patients to secure transportation, schedule appointments, and navigate burdensome administrative processes are especially challenging for people who use drugs. Novel implementation strategies, including low barrier technology mobile HIV primary care services that transcend traditional care models, are necessary to better engage this population in HIV primary care. The University of California, San Diego (UCSD) Owen Clinic which is the largest and most comprehensive HIV Medicine Clinic in San Diego aims to establish and evaluate low barrier technology mobile HIV primary care services in close collaboration with the County of San Diego Harm Reduction Services Program. We propose parking a UCSD mobile unit adjacent to the newly established County of San Diego Harm Reduction Services Program with the goal of increasing engagement in HIV primary care in people who use drugs. This project will support the establishment of key infrastructure (telehealth, electronic storage lockers with keypads for participant medication and substance use equipment storage, and vein finding equipment for phlebotomy in people who inject drugs) trained personnel, and data recording systems to enable the implementation and evaluation of low barrier technology mobile HIV primary care to address the ongoing HIV public health crisis and work toward ending the HIV epidemic in San Diego. The implementation of the ‘Owen Low Barrier Care Mobile HIV Clinic’ will leverage the community collaboration with the County of San Diego and evidence-based low barrier mobile HIV primary care treatment and technology strategies to strive to overcome the multiple socio-structural barriers to HIV primary care faced by people who use drugs in San Diego.  

Principal Investigator: Angela Bazzi 

Budget: $123,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: With ongoing opioid and polysubstance use crises in California and nationwide, HIV transmission has increased among people who use and inject drugs (hereafter, PWUD). HIV testing is a critical entry point into the HIV prevention and care cascades, yet stigma and additional multilevel barriers limit access to facility-based HIV testing for PWUD. Even within syringe services programs (SSPs), competing priorities and resource constraints challenge the consistent provision of HIV testing. Harm reduction vending machines (HRVMs) are a promising approach for extending SSPs’ delivery of a range of HIV prevention supplies to PWUD, including syringes and other sterile drug use equipment, condoms, and HIV self-test kits. However, despite several decades of successful HRVM implementation internationally, this low-barrier technology has only recently gained traction among U.S. harm reduction programs, and important knowledge gaps persist regarding acceptability, feasibility, and factors that support equitable reach for HIV prevention, including among racially and ethnically diverse and unhoused PWUD. Furthermore, the acceptability of specific innovations in HRVM technology (e.g., biometric identification, data collection systems, telehealth capabilities) remain understudied among PWUD. Our research partner, DAP Health, operates one HRVM in downtown Palm Springs, CA, and hopes to expand to additional locations (e.g., public spaces) to better reach diverse communities (e.g., unhoused, rural, and tribal) across the medically-underserved Ending the HIV Epidemic (EHE) priority jurisdictions of Riverside and San Bernadino Counties. Leveraging our ongoing research partnership (between DAP Health, UC San Diego, and San Diego State University; NIH grant R34DA058389), we will purchase another HRVM and conduct a one-year study comparing locations and investigating implementation barriers, facilitators, and optimal strategies to help equitably and sustainably expand the reach of DAP Health’s HRVMs. By engaging a diverse range of implementation partners, including PWUD, harm reduction specialists, HIV service providers, community organizers, health department representatives, and policymakers, findings will directly inform efforts to expand HRVM implementation as a promising low-barrier technology for addressing HIV prevention and care in this region and beyond.  

Principal Investigator: Brittany Bryant 

Budget: $108,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: California’s Ending the Epidemic Strategic Plan identifies Black adolescent girls as disproportionately affected by HIV and STIs, with Black adolescents representing 51% of HIV diagnoses among U.S. adolescents aged 13-19 in 2020. Given the high rates of chlamydia, gonorrhea, and syphilis among Black girls, there is an urgent need for accessible, culturally tailored prevention interventions. The SIHLE (Sisters Informing, Healing, Living, and Empowering) intervention has proven effective in reducing HIV-related sexual risk behaviors through culturally relevant programming. Originally adapted to a web-based format (SIHLEweb) in 2013, further modernization is required to align with current technological trends, particularly mobile health solutions. Our overarching research goal is to design and test the effectiveness of a culturally tailored HIV prevention intervention mobile app for young Black girls (SIHLEapp) using the IDEAS Framework. As a preliminary step towards this goal, our aims for the current research study are to 1) explore preferred adaptation and implementation options of SIHLEapp through qualitative interviews with Black girls aged 13-18; and 2) explore potential targets for modernization of the SIHLE intervention through qualitative interviews with key stakeholders, including Black mothers or maternal figures and sexual health providers.  

Findings will guide the development of SIHLEapp and support future funding applications to CHRP or NIH. 

Principal Investigator: Susan Cassels 

Budget: $94,435 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: This proposal aims to address the ongoing HIV epidemic among sexual minority men (SMM) who are experiencing housing insecurity in Los Angeles (LA) by 1) collating the current access to low barrier spatially-variable HIV prevention and care, 2) mapping geographic prevention and care deserts in LA county, and 3) conducting a rapid needs assessment so that the most accurate and beneficial low barrier technologies can be strategically placed across the county.  

Spatial approaches to improving health of minoritized populations is critical since geographic access can pose significant barriers to uptake of interventions. Given the vast geography of the LA county region, it is imperative to better understand how different technologies will work in differing areas so that relevant needs are addressed adequately. Preliminary research by the PI has identified unique geo-spatial patterns that suggest different low barrier technologies will be relevant in different areas based on social behaviors (e.g., where PLWH experiencing homelessness sleep, where SMM engage in sexual encounters, and where SMM engage in substance use, etc.). Low-barrier HIV prevention and care must be geographically and temporally-specific, in order to maximize efficacy. 

Low barrier technologies for HIV prevention and care are especially important for people who are insecurity housed. Sexual minority populations experience housing insecurity at rates higher than heterosexual populations, especially SMM of color.  Housing insecurity is predictive of poor self-rated health among SMM (5), poor mental health, and poor HIV-related outcomes. The mechanisms that link housing insecurity to poor HIV outcomes include delayed, reduced or postponed health care or medications, higher rates of mental health disorders, substance use, and poor adherence to antiretroviral treatment. However, geographically responsive HIV treatment and care services, including mobile HIV testing vans or street-based PrEP outreach that meets people where they need services, can improve HIV-related outcomes.

Principal Investigator: Indrani Choudhuri 

Budget: $143,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract:  The advent of antiretroviral therapy (ART) has substantially improved the management of HIV/AIDS, yielding greater viral suppression, transmission prevention, and improved health outcomes for patients. However, drug resistance, including to the latest generation ART, is becoming a more pervasive clinical problem. Because resistant viruses typically replicate less efficiently than non-resistant viruses, whether a drug-resistant mutation (DRM) persists in the viral population depends on the intricate tradeoff between resistance and fitness. Here, we note one important and novel consideration. The occurrence and effect of DRMs in response to ART are strongly dependent on the specific genetic sequence background in which the mutation occurs. Previously, we showed that the fitness effect of primary DRMs can vary widely within and between patient populations due to epistatic interactions of the DRM with the sequence background of the virus. Accordingly, laboratory-derived molecular HIV clones, such as NL4-3, HxB2, or LAI IIIB, often fail to accurately reflect the complex genetic backgrounds of patient-derived viral sequences. Unfortunately, current methods for evaluating fitness effects of patient-derived DRMs rely on these same laboratory-derived molecular viral clones. To address this discrepancy, we propose to develop a novel machine-learning-based lightweight and ready-to-use software to predict the differential effects of DRMs premised on individual patient sequence backgrounds. The proposed software will leverage comprehensive HIV sequence data from patients in the Stanford and Los Alamos HIV databases to predict the fitness effects of DRMs in various patient-derived sequences. We aim to provide an accurate, easy-to-use, and reliable tool that can be developed as an application for clinicians for the potential assessment of drug resistance in patients, thus facilitating the development of tailored treatment strategies, including but not limited to the prescription of better combination regimens. This tool would represent a significant advance in bridging the gap between laboratory-based predictions and real-world patient scenarios. Its implementation could make costly DRM testing alternatives available to underserved communities, optimize treatment efficacy in diverse patient populations, and yield more effective personalized treatment strategies for HIV. 

Principal Investigator: Tommi Gaines 

Budget: $129,440 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: While substantial progress has been made in preventing and treating HIV, American Indians and Alaska Natives (AI/AN) continue to be overlooked. From 2018 to 2022, the rate of new HIV diagnoses remained stable or decreased for most racial/ethnic groups in the United States except for AI/AN who experienced a 30% increase in new diagnoses. Approximately 20% of AI/AN living with HIV are unaware of their infection status compared to 13% of the general US population living with an undiagnosed infection. Adding to the HIV burden is the disproportionate rate of sexually transmitted infections. Compared to other racial/ethnic groups, AI/AN have the highest rate of syphilis and the second highest rate of chlamydia and gonorrhea, indicating sexual practices that could heighten HIV vulnerabilities. 

To advance health equity in HIV prevention and treatment, our academic team partnered with a Southern California Tribe. We examined the feasibility of integrating HIV self-testing within their tribal wellness program. We found that most community members preferred home-based testing over clinic-based options, with nearly half interested in obtaining self-test kits through the tribal wellness program. Recently, we launched a new collaboration to evaluate a public health vending machine (PHVM) that freely dispenses naloxone and fentanyl testing strips on the Tribe. In its first year, the PHVM has been utilized over 100 times, indicating strong community engagement and the potential to expand its utility. We will build upon this collaboration by examining the appropriateness and feasibility of offering low-barrier access to HIV prevention and other harm reduction resources through an interactive touchscreen vending machine. In contrast to the PHVM currently installed on the Tribe, the touchscreen vending machine will be able to provide on-demand training, offer resources for continuum of care, provide referrals, and collect non-identifying data. The resources, training and materials can be updated on demand to keep up with the latest information available. In addition, a touchscreen vending machine is video capable and can hold telehealth appointments.

Principal Investigator: Thomas Martin 

Budget: $108,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: Over 40% of people with diagnosed HIV (PWH) in San Diego County have unsuppressed viral load (VL) putting them at risk of the complications of HIV and transmission of HIV to others. Strategies to improve the identification of PWH who are out of care could lead to improved resource allocation and provision of preventive services.  

Existing strategies to identify PWH who are out of care include ‘data-to-care’ programs that use data reported routinely to public health. Typical algorithms prioritize PWH with no HIV VL or CD4 T-cell measurement in the prior 12 months. However, this strategy identifies many PWH that have moved, receive care at a non-reporting institution, are incarcerated, or are deceased. It is also retrospective in nature and results in delays in outreach or difficulty contacting individuals. This leads to inefficient use of public health resources. 

Machine learning (ML) algorithms incorporate multi-dimensional data with the ability to not only find pertinent associations but to also make predictions of future outcomes. Preliminary work by our group indicates that applying ML to county HIV data can provide prediction of which PWH are likely to fall out of care, defined by future unsuppressed VL. Our work incorporates novel HIV testing pattern variables such as frequency of VL tests, variance in test intervals, VL trends, and VL blips in addition to traditional risk factors. In our preliminary work, the ML algorithm has a positive predictive value over 60% meaning that for over half the identified PWH, their next VL will be unsuppressed indicating they are either out of care or poorly engagement with care. 

We propose to develop our ML tool comparing different statistical approaches and to evaluate which provides the best predictive power. We will develop the novel variables used to optimize variable selection to capture details of VL testing such as blips, variability in testing intervals, and testing frequency. Finally, we propose to compare the performance of traditional ‘data-to-care’ algorithms with ML algorithms for the identification of PWH who are out of care.  

By developing ML, we aim to improve public health identification of PWH who are at risk of falling out of care. With improved identification, we will provide the groundwork for novel, timely, intensive, and multi-modal interventions to improve care for PWH in California.

Principal Investigator: Stephanie Myers-Pantele 

Budget: $100,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: California continues to have co-occurring opioid-related overdose and infectious disease transmission (e.g., HIV and Hepatitis C [HCV]) epidemics. State-level data indicate there were substantial increases (33.2%) in opioid-related overdose deaths between 2020-2021,1 and that people who inject drugs (PWID) comprise 5% and 68% of new HIV and HCV diagnoses, respectively. Orange County, an Ending the HIV Epidemic (EHE) priority jurisdiction, has notably seen a 13.3% increase in the number of HIV cases among PWID between 2013 and 2022 despite seeing significant decreases among other exposure categories (e.g., men who have sex with men and heterosexual contact).   Research also suggests that PWID experience numerous social and structural barriers to healthcare (e.g., stigma, homelessness, transportation challenges) that limit their ability to engage in HIV and overdose prevention services. Compounding these barriers further, Orange County’s political climate has been hostile towards state-approved, evidence-based harm reduction strategies for people who use drugs (PWUD; e.g., syringe service programs).  As such, there is a critical need for novel HIV prevention and other harm reduction efforts to improve health outcomes for PWUD in this region. In response, the proposed research seeks to explore the feasibility and acceptability of harm reduction vending machines (HRVMs) among PWUD and relevant service providers, law enforcement, and community members in Orange County, California. HRVMs are innovative, low-barrier, technology-based options that expand access to supplies and engage harder to reach populations, by dispensing harm reduction materials such as syringes, naloxone, fentanyl test strips, condoms, and HIV, HCV, and STI self-test kits. Guided by the Consolidated Framework for Implementation Research (CFIR), the proposed research will employ qualitative methods to assess the perceived barriers and facilitators to HVRM adoption and implementation, potential HVRM locations, and desired materials via in-depth interviews with ~20-30 PWUD (Aim 1) and via key informant interviews with ~20-30 staff, clinicians, and health care professionals serving PWUD, law enforcement, and community members (Aim 2), in Orange County. This information will be critical for seeking potential funding for a future Hybrid Type I pilot of HVRMs in this context. 

Principal Investigator: Jennifer Nations 

Budget: $100,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: Unhoused individuals have poorer HIV health outcomes, perpetuating disparities in California even as the HIV epidemic slows in the state. These findings suggest that current strategies for ending the epidemic, including the use of low-barrier technologies for prevention and treatment, are not reaching unhoused individuals at the same rate they reach those with stable housing. Unhoused individuals face daily challenges to meeting basic needs that make HIV prevention and treatment a last priority. Continual displacement of unsheltered homeless people further disrupts their ability to access care: encampment sweeps lead to the loss of belongings and create literal and relational distance between healthcare providers and clients, both of which can disrupt access to HIV interventions.  

Safe sleeping, or sanctioned encampment, sites may minimize the disruption in access to HIV technologies. Such sites provide individuals with a place to sleep without fear of being ticketed, pushed out, or arrested. Safe sleeping sites are low-barrier, meaning that individuals do not need identification to enter and do not need to adhere to sobriety rules (although they cannot use substances on-site). Clients are able to access a range of services, including showers, laundry, food, and medical care. Because safe sleeping provides individuals with a settled location, they may be an important site for mobile health services and the implementation of low barrier technology HIV interventions, including the use of medication adherence phone apps, vending machines for HIV testing kits, or safe boxes for storing belongings.   

This study will take place in the City of San Diego. San Diego is one of 50 jurisdictions that account for more than half of all new HIV diagnoses in the U.S. High transmission rates in the city may in part be connected to the high volume of people experiencing homelessness. San Diego opened two safe sleeping sites in October 2023 after the city policymakers banned homeless encampments in public places. This study will engage a partnership between UC San Diego researchers, the City of San Diego, and program providers at the city’s safe sleeping sites. Our project will employ focus groups and individual interviews with providers and clients to determine if safe sleeping sites can overcome the problems inherent in utilizing low barrier technology HIV interventions.

Principal Investigator: Tessa Rife-Pennington 

Budget: $108,000 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: In 2022, California had the highest prevalence of people living human immunodeficiency virus (HIV) of all states. There were 4,882 new HIV diagnoses, and rates were highest in cisgender men, Black/African American and Latinx individuals, and men who have sex with men (MSM). HIV prevalence is also high among Veterans with history of opioid/alcohol use disorders, hepatitis B/C virus and sexually transmitted infections, and homelessness. HIV testing is essential for early detection and to reduce morbidity, mortality, and costs. Yet in 2020, approximately 12% of people living in California with HIV were unaware of their infection. As of 2023, 50% of Veterans in care had never been tested for HIV.   

Barriers to HIV testing include stigma, racism, homophobia, and lack of cultural competence in healthcare settings; lack of knowledge or access; cost and confidentiality concerns; low income, education, or perceived benefit; unemployment; and incarceration. Despite barriers, Veterans often want HIV testing and to know their results. Use of HIV self-tests (HIVST), where a person self-collects an oral fluid sample, tests, and reads the results, is an evidence-based strategy to increase testing uptake and address barriers. Further, distribution via vending machines (VMs) is an innovative, low barrier, technology-based approach demonstrated to increase confidentiality, privacy, and convenience. It is feasible, acceptable, and preferable over in-clinic testing, which facilitates engagement with first-time testers and hard-to-reach individuals, and those with a positive test often seek further testing/treatment.  

Most evidence for VM-dispensed HIVSTs is among MSM, in the United Kingdom, Africa, and Los Angeles, California, and in commercial sex venues/public spaces. No studies have examined impacts of Veteran self-administered HIV tests or distribution via VMs. We aim to bridge this gap by evaluating the first VM-dispensed HIVSTs designed for Veterans, located in Northern California, and in healthcare and supportive housing settings. We will collect Veteran self-report data via electronic surveys and HIVST distribution data via software from 15 VMs to evaluate Reach, Effectiveness, Adoption, Implementation, and Maintenance (RE-AIM). Study results may inform expansion of HIVST availability and delivery via VMs for Veterans and in healthcare and community-based settings.

Principal Investigator: Nadir Weibel 

Budget: $97,223 

Start Date: March 1, 2025        End Date: February 28, 2026 

Project Abstract: Effective communication between healthcare teams and patients is crucial for reducing barriers to prevention and care. Good communication leads to better healthcare access, engagement in prevention efforts, effective diagnoses, treatment adherence, and emotional well-being. However, implicit bias, linked to factors like sexual orientation and race, can negatively impact patient access to care, especially for people living with HIV (PLWH). Addressing implicit bias requires self-awareness and practice in difficult communication situations. 

This project aims to design, develop, and validate an AI-based tool to help HIV care teams — including providers, nurses, social workers, counselors, and researchers — improve communication practices and reduce biases. Building on our recent UnBIASED project, which explored using social signals as indicators of implicit bias, ConversHIVe will leverage Generative AI through Large Language Models (LLMs) to provide rapid simulation and feedback.  ConversHIVe will offer easy access to AI-driven simulated patients and an interface that detects, quantifies, and visualizes the user’s social signals during interactions. 

ConversHIVe aligns with the California HIV/AIDS Research Program (CHRP) mission by addressing barriers in HIV prevention and care, particularly for marginalized communities. By enhancing service providers' communication and reducing implicit bias, ConversHIVe supports CHRP’s priorities of improving healthcare delivery and access. The project also aligns with national strategies for ending the HIV epidemic, focusing on diagnosing, treating, preventing, and responding to HIV. 

The study will use a mixed-methods design, integrating quantitative and qualitative approaches, and will be conducted with the HIV Owen Clinic at UCSD, the AntiViral Research Center (AVRC) Community Advisory Board (CAB), and community-based organizations in San Diego. The study population includes healthcare providers in HIV clinics serving marginalized communities. The intervention involves using ConversHIVe, an AI-driven web interface providing simulated patient interactions and real-time feedback. Primary outcomes include improved communication skills, reduced implicit bias, and enhanced patient-provider interactions.