Associations between perceived illicit fentanyl use and infectious disease risks among people who inject drugs

Decentralized HIV testing: comparing peer and mail-based distribution strategies to improve the reach of HIV self-testing among people who use drugs in Florida

INTRODUCTION

People who use drugs (PWUD) are at increased risk for HIV infection. HIV self-testing (HIVST) is a promising method for identifying new infections, but optimal distribution strategies remain understudied.

METHODS

To characterize PWUD by HIVST distribution strategy (peers vs. mail), we examined data from July 2022 to June 2023 collected from a real-world HIVST program led by the non-profit, Florida Harm Reduction Collective. We used descriptive statistics and Poisson regressions with robust error variance to compare those who received HIVST through peers or via mail by socio-demographics, Ending the HIV Epidemic (EHE) county designation, and HIV testing experience.

RESULTS

Among 728 participants, 78% received HIVST from peers, 47% identified as cisgender female, 48% as heterosexual, and 45% as non-White; 66% resided in an EHE county, and 55% had no HIV testing experience. Compared to those who received an HIV self-test from peers, those who received tests via mail were less likely to be cisgender male (vs. cisgender female; prevalence ratio [PR] = 0.59, 95% confidence interval [CI]: 0.43, 0.81), non-Hispanic Black (vs. non-Hispanic White; PR = 0.57, 95% CI: 0.36, 0.89) or from EHE counties (vs. non-EHE counties; PR = 0.33, 95% CI: 0.25, 0.44). Those who received tests via mail were also more likely to identify their sexual orientation as "Other/Undisclosed" (vs. straight/heterosexual; PR = 2.00, 95% CI: 1.51, 2.66).

CONCLUSION

Our findings support the role of community-based HIVST distribution strategies in increasing HIV testing coverage among PWUD. Additional research could help inform the equitable reach of HIVST.

Preexposure Prophylaxis (PrEP) for HIV Prevention at Outpatient Substance Use Treatment Facilities, United States, 2021

Objectives. To determine the percentage of US outpatient substance use treatment facilities that offer HIV preexposure prophylaxis (PrEP). Methods. We used a retrospective cross-sectional design with data from the National Substance Use and Mental Health Services Survey, which was administered to directors of US outpatient substance use treatment facilities in 2021. We evaluated the percentage of outpatient substance use treatment facilities offering PrEP and factors associated with the likelihood of offering PrEP. Results. We included 12 182 outpatient substance use treatment facilities. Of these, 637 (5.2%) offered PrEP. Offering HIV treatment (adjusted odds ratio [AOR] = 45.3; 95% confidence interval [CI] = 36.0, 56.9) and offering programs for LGBTQ (lesbian, gay, bisexual, transgender, and queer or questioning) people (AOR = 1.3; 95% CI = 1.0, 1.6) were associated with higher likelihoods of offering PrEP. Conclusions. PrEP is highly effective and recommended for patients at risk for HIV from injection drug use. Nearly 95% of US outpatient substance use treatment facilities did not offer PrEP-a missed opportunity for harm reduction through primary HIV prevention. Public Health Implications. Diversification of the array of available HIV PrEP options and the ongoing HIV and opioid use epidemics require outpatient substance use treatment facilities to expand PrEP availability. (Am J Public Health. Published online ahead of print May 30, 2024:e1-e5. https://doi.org/10.2105/AJPH.2024.307699).

Safe Injection Self-Efficacy is associated with HCV and HIV seropositivity among people who inject drugs in the San Diego-Tijuana border region

Background

Safe injection self-efficacy (SISE) is negatively associated with injection risk behaviors among people who inject drugs (PWID) but has not been examined in differing risk environments. We compared responses to a validated SISE scale between PWID in San Diego, California and Tijuana, Mexico, and examine correlates of SISE among PWID in Tijuana.

Methods

PWID were recruited via street outreach for a longitudinal cohort study from October 2020 - September 2021. We compared SISE scale items by city. Due to low variability in SISE scores among San Diego residents, we restricted analysis of factors associated with SISE to Tijuana residents and identified correlates of SISE scores (low, medium, high) using ordinal logistic regression.

Results

Of 474 participants, most were male (74%), Latinx (78%) and Tijuana residents (73%). Mean age was 44. Mean SISE scores among San Diego residents were high (3.46 of 4 maximum) relative to Tijuana residents (mean: 1.93). Among Tijuana residents, White race and having previously resided in San Diego were associated with higher SISE scores. HCV and HIV seropositivity, homelessness, fentanyl use, polysubstance co-injection, and greater injection frequency were associated with lower SISE scores.

Conclusions

We found profound inequalities between Tijuana and San Diego SISE, likely attributable to differential risk environments. Associations with fentanyl and polysubstance co-injection, injection frequency, and both HIV and HCV seropositivity suggest that SISE contribute to blood-borne infection transmission risks in Tijuana. SISE reflects an actionable intervention target to reduce injection risk behaviors, but structural interventions are required to intervene upon the risk environment.

Long-acting Injectable PrEP Interest and General PrEP Awareness among People who Inject Drugs in the San Diego-Tijuana Border Metroplex

Long-acting injectable HIV pre-exposure prophylaxis (LAI-PrEP) could help overcome multilevel challenges to HIV prevention for people who inject drugs (PWID), including those in the binational San Diego-Tijuana metroplex. Yet, general PrEP awareness and interest in LAI-PrEP remain underexplored among PWID. From 2020 to 2021, 562 HIV-negative PWID in San Diego and Tijuana completed surveys assessing general PrEP awareness and interest in oral and LAI-PrEP. Modified Poisson regression examined factors associated with general PrEP awareness. Multinomial logistic regression assessed factors associated with interest in both oral and LAI-PrEP, oral PrEP only, LAI-PrEP only, or neither. General PrEP awareness was low (18%) and associated with experiencing unsheltered homelessness (adjusted prevalence ratio [APR] = 1.50, 95% confidence interval [CI]: 0.96-2.33), past 6-month fentanyl injection (APR = 1.53, 95% CI: 1.04-2.25), and transactional sex (APR = 1.71, 95% CI: 1.06-2.76). Interest in oral PrEP only was most common (44%), followed by LAI-PrEP only (25%) and neither (16%). Compared to the odds of being interested in LAI-PrEP only, the odds of being interested in oral PrEP only were lower among those who were stopped by police (AOR = 0.38, 95% CI: 0.22-0.65), reported past 6-month fentanyl injection (AOR = 0.33, 95% CI: 0.20-0.56), polydrug use (AOR = 0.48, 95% CI: 0.27-0.86), injecting multiple times daily (AOR = 0.26, 95% CI: 0.14-0.46), receptive syringe use (AOR = 0.30, 95% CI: 0.19-0.49), and higher perceived HIV risk (AOR = 0.24, 95% CI: 0.15-0.39). Interest in LAI-PrEP was more common among PWID reporting social and structural factors that could interfere with oral PrEP adherence, suggesting LAI-PrEP implementation could increase PrEP coverage among those most vulnerable to HIV.

Longitudinal patterns of use of stimulants and opioids in the AIDS linked to the IntraVenous experience cohort, 2005-2019

BACKGROUND

Overdoses involving opioids and stimulants are on the rise, yet few studies have examined longitudinal trends in use of both substances. We sought to describe use and co-use of opioids and stimulants, 2005-2019, in the AIDS Linked to the Intravenous Experience (ALIVE) cohort - a community-based cohort of people with a history of injection drug use living in or near Baltimore, MD.

METHODS

We included 2083 ALIVE participants, who had at least two visits during the study period. Our outcome was based on self-reported use of opioids and stimulants in the prior 6 months. We estimated prevalence of 4 categories of use (neither stimulants nor opioids, only stimulants, only opioids, stimulants and opioids), using a non-parametric multi-state model, accounting for the competing event of death and weighting for informative loss to follow-up. All analyses were stratified by enrollment cohort, with the main analysis including participants who enrolled prior to 2015 and a sub-analysis including participants who enrolled 2015-2018.

RESULTS

In the main analysis, prevalence of using stimulants and opioids decreased from 38 % in 2005 to 12 % 2013 but stabilized from 2014 onwards (13-19 %). The prevalence of using only stimulants (7-11 %) and only opioids (5-10 %) was stable across time. Participants who reported using both were more likely to report homelessness, depression, and other substance use (e.g., marijuana and heavy alcohol use) than participants in the other use categories. On average, 65 % of visits with use of both were followed by a subsequent visit with use of both; of participants transitioning out of using both, 13% transitioned to using neither.

CONCLUSIONS

While use of stimulants and opioids declined in the cohort through 2013, a meaningful proportion of participants persistently used both. More research is needed to understand and develop strategies to mitigate harms associated with persistent use of both stimulants and opioids.

Regional differences in fatal drug overdose deaths among Black and White individuals in the United States, 2012-2021

BACKGROUND AND OBJECTIVES

The current study examines regional differences in Black/White fatal drug overdoses.

METHODS

Black/White overdose mortality data (2012-2021; N = 537,085) were retrieved from CDC WONDER. We used death counts and corresponding Census Bureau population estimates by the decedent's age and race/ethnicity to calculate mortality rate ratios.

RESULTS

From 2012 to 2021, there were 537,085 reported overdose deaths among White (85%) and Black (15%) individuals in the United States. In the South, Black individuals had lower fatal drug overdose deaths than their same-aged White counterparts. In the Northeast, Midwest, and West regions, Black individuals had around 10%-60% lower likelihood of overdoses among younger ages (15-24, 25-34, 35-44) but about 60%-300% higher likelihood of overdoses among older adults (55-64). Increases in overdose deaths during the pandemic (2020-2021) led to changes in Black/White overdose death patterns, whereas Black individuals of all ages in the Midwest and West regions had approximately 15%-425% higher likelihood of fatal overdoses than their same-aged White counterparts. Sex-stratified analysis suggests that Black females in the South had overdose death rates around 50% lower than same-aged White females, and overdose deaths were relatively equal for Black and White females in the Midwest-patterns not seen among males.

CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE

The findings indicate that the Black/White overdose mortality gap changed after the COVID-19 pandemic across all regions and age cohorts, with state and regional variations in magnitude. Behavioral interventions and policies to curb drug overdose deaths among populations most impacted should consider regional, sex, and age-related differences.

Health, harm reduction, and social service providers' perspectives on the appropriateness and feasibility of peer distribution of HIV self-test kits among people who use drugs

BACKGROUND

People who use drugs (PWUD) experience elevated HIV risk and numerous barriers to facility-based HIV testing. HIV self-testing (HIVST) could circumvent many of those barriers and is acceptable among PWUD, yet HIVST implementation for PWUD is limited. Service providers' perspectives on specific HIVST delivery strategies could help increase availability for PWUD.

METHODS

From April-November 2021, we interviewed 16 health, harm reduction, and social service providers working with PWUD in San Diego, CA. Interviews and rapid thematic analysis explored perspectives on HIVST's utility and appropriateness, as well as the feasibility of and anticipated challenges with specific HIVST delivery strategies, including peer or secondary distribution.

RESULTS

Participants viewed HIV as a significant threat to PWUD health and confirmed the presence of numerous barriers to local facility-based HIV testing. Participants viewed HIVST as a promising and potentially empowering solution. Based on community familiarity with secondary distribution of harm reduction supplies (i.e., naloxone) and information, participants viewed secondary distribution of HIVST kits as an appropriate and feasible strategy for increasing the reach of HIVST, but also described potential barriers (e.g., engaging socially disconnected individuals, ensuring linkages to services following HIVST) and provided suggestions for alternative HIVST kit delivery models (e.g., harm reduction vending machines).

CONCLUSIONS

Service providers viewed secondary distribution of HIVST kits among PWUD as promising, appropriate, and feasible, yet specialized efforts may be needed to reach the most marginalized individuals and ensure consistent provision of educational information and referral supports that maximize the impact of this approach.

Health risks associated with smoking versus injecting fentanyl among people who use drugs in California

BACKGROUND

Given the attention, funding, and services that seek to reduce overdose mortality from fentanyl, it is important to understand whether a potential solution is for more people to switch from injecting to smoking fentanyl. As such, we set out to conduct a study to compare health and healthcare utilization outcomes associated with different modes of illicit fentanyl administration.

METHODS

From January to February 2023, we recruited people who use drugs from 34 syringe services programs across California, USA (N=999) and surveyed their substance use, health outcomes, and healthcare utilization. We compared health risks among people who injected fentanyl (78% of whom also smoked) to people who solely smoked fentanyl (n=563).

RESULTS

Of the 563 participants, forty-one percent injected fentanyl and 59% only smoked fentanyl. People who injected fentanyl were 40% more likely to have experienced a non-fatal overdose in the past 3 months (27% vs. 19%; aRR=1.40; 95% CI=1.03, 1.93) and 253% more likely to have had a skin and soft tissue infection in the past 3 months (39% vs. 15%; aRR=2.53; 95% CI=1.74, 3.67), compared to people who only smoked fentanyl. The average number of nights spent in the hospital was higher among people who injected fentanyl (average 1.2 nights vs. 0.7 nights; aIRR=1.78; 95% CI=1.02, 3.09; p=0.04).There were non-significant associations between mode of fentanyl administration and number of emergency department visits and probability of hospitalization.

CONCLUSIONS

Findings suggested that people who injected fentanyl were at higher risk for overdose and skin and soft tissue infections than people who only smoked fentanyl. Distribution of safe smoking supplies may facilitate transitions from injecting to smoking fentanyl, thereby reducing health risks associated with fentanyl use.

Characterizing Opioid Withdrawal Experiences and Consequences Among a Community Sample of People Who Use Opioids

BACKGROUND

Opioid withdrawal symptoms are a highly salient and consequential health condition experienced by people who use opioids (PWUO). This study utilized qualitative interviews to explore opioid withdrawal experiences and consequences among PWUO in Los Angeles County, USA.

METHODS

Semi-structured qualitative interviews were conducted with 22 PWUO (aged 27-63 years) between May 2021 and May 2022. Participants self-reported opioid and injection drug use in the last 30 days. We employed an inductive thematic approach to systematically code and synthesize textual interview data.

RESULTS

Participants experienced withdrawal symptoms frequently, with many going to great lengths to avoid them. Withdrawal pain was described as incapacitating and interfered with PWUO's ability to sustain regular employment and ensure stable housing. Avoiding withdrawal was described as influential in driving decisions to continue using opioids. Mechanisms for managing withdrawal included using other substances to the point of sedation. PWUO who transitioned from heroin to fentanyl use revealed more frequent, painful, and faster onset of withdrawal symptoms. Adverse withdrawal experiences and fear of precipitated withdrawal from buprenorphine were barriers to treatment initiation and continuation.

CONCLUSION

Withdrawal symptoms among PWUO increase health risk. Improved strategies to treat opioid withdrawal are urgently needed. Solutions such as safe supply and intentional opioid withdrawal interventions (educational trainings, withdrawal comfort kits) are needed to improve withdrawal management and reduce opioid-related harm.

Testing the test strips: laboratory performance of fentanyl test strips

BACKGROUND

The overdose crisis driven by synthetic opioids continues to escalate in the USA. We evaluated the efficacy of multiple manufacturing lots of a fentanyl test strip (FTS) to detect fentanyl and fentanyl analogs and assessed cross-reactivity with possible interferences.

METHODS

Drug standards were dissolved in water in a laboratory setting and serially diluted. Drug dilutions were tested using five different manufacturing lots of BTNX Rapid Response (20 ng/mL cutoff) lateral flow chromatographic immunoassay strips to assess lot-to-lot variability for FTS sensitivity and cross-reactivity for the analytes of interest.

RESULTS

All five manufacturing lots cross-reacted with fentanyl and eleven fentanyl analogs. Diphenhydramine, lidocaine, MDMA, and methamphetamine were found to cause false positives with the strips. There was notable lot-to-lot variability in the sensitivity of the strips for fentanyl, fentanyl analogs, and known interferences.

DISCUSSION

FTS remains an important overdose prevention tool, but lot-to-lot variability in performance complicates robust instructions that balance the prevention of false positives and false negatives. Continued lot-to-lot performance assessment is recommended to ensure health education for FTS remains accurate. More sophisticated drug checking technologies and services are needed in the community landscape to augment personal FTS use to facilitate informed consumption and overdose risk mitigation.

Willingness to use and distribute HIV self-testing kits among people who inject drugs in the San Diego-Tijuana border region

BACKGROUND

HIV self-testing (HIVST) could increase HIV testing access among people who inject drugs (PWID), and secondary distribution (i.e., peer-delivery) of HIVST kits in PWID social networks could further expand coverage. We assessed willingness to use and distribute HIVST kits among PWID in the San Diego-Tijuana border region.

METHODS

From 2020 to 2021, HIV-negative PWID in San Diego, USA, and Tijuana, Mexico, completed surveys and provided data on individual (N = 539) and social network (N = 366) characteristics. We used modified Poisson regression to examine the effects of individual and social network characteristics on willingness to use and distribute HIVST kits.

RESULTS

Most participants were willing to use (81%) and distribute (81%) HIVST kits. At the individual level, prior HIV testing was positively associated with willingness to use (adjusted prevalence ratio [aPR] = 1.24, 95% confidence interval [CI] 1.10-1.40) and distribute (aPR = 1.27, 95% CI 1.12-1.43) HIVST kits, while perceiving oneself to be at higher HIV risk than others was negatively associated with willingness to use HIVST kits (aPR = 0.83, 95% CI 0.74-0.93). At the network level, willingness to distribute HIVST kits was positively associated with network size (aPR = 1.04 per member, 95% CI 1.01-1.08) and greater proportions of one's network encouraging them to use drugs (aPR = 1.29, 95% CI 1.16-1.44) and having a history of homelessness (aPR = 1.51, 95% CI 1.31-1.74) or detention/arrest (aPR = 1.57, 95% CI 1.36-1.82), and negatively associated with a greater proportion of one's network including "very close" persons (aPR = 0.80, 95% CI 0.69-0.94).

CONCLUSIONS

We found high potential for HIVST kits and their secondary distribution to increase HIV testing among PWID who face the greatest barriers to facility-based testing.

Injection Behaviors and Use of Syringe Service Programs over Time among People Who Inject Drugs in Baltimore, Maryland

Introduction: People who inject drugs (PWID) are at increased risk for infectious disease transmission, including hepatitis C and HIV. Understanding trends in injection risk behaviors and syringe service program (SSP) use over time can help improve infectious disease prevention and other harm reduction services. Methods: Using National HIV Behavioral Surveillance System data from Baltimore, Maryland, we examined changes in receptive sharing of (1) syringes, (2) injection equipment, (3) syringes to divide drugs; and (4) receipt of syringes from SSPs among PWID from 2009 to 2018 (n = 518 in 2009, n = 638 in 2012, n = 586 in 2015, and n = 575 in 2018) using unadjusted and adjusted logistic models calculated across time for the total sample. Results: The conditional probability of receptive sharing of syringes and receipt of syringes from SSPs remained relatively stable, while receptive sharing of injection equipment and receptive sharing of syringes to divide drugs dropped substantially after 2009. White race and daily injection frequency were positively associated with sharing syringes and injection equipment and negatively associated with SSP use over time. In 2015, there was a notable shift such that women were twice as likely as men to receive syringes from SSPs and less likely than men to report the use of shared syringes or equipment. Conclusion: Findings indicate overall steady or decreasing trends in injection risk and steady trends in SSP usage over time, with some notable improvements among women and indications of shifting drug market patterns. Injection-related risk behaviors remain high among White PWID and may require targeted outreach and interventions.

Acceptability and Feasibility of a Mobile Phone Application to Support HIV Pre-exposure Prophylaxis Among Women with Opioid Use Disorder

Despite evidence supporting HIV pre-exposure prophylaxis (PrEP) effectiveness, very few women with opioid use disorder (OUD) take PrEP. Interventions that improve medication assisted treatment (MAT) uptake and adherence may also be beneficial for PrEP. The reSET-O mobile phone app is a component of the evidence-based Therapeutic Education System, which improves retention and abstinence for people with OUD. To better understand use of this mobile health tool as a support for PrEP among women with OUD, pre-implementation contextual inquiry is needed. Therefore, we set out to assess target user characteristics, implementation barriers, feasibility, and acceptability of reSET-O. We recruited women with OUD receiving care from a community-based organization in Philadelphia to complete semi-structured interviews. All participants were prescribed reSET-O. We interviewed 20 participants (average age 37 years; 70% white, 15% Hispanic, 5% Black) from 5/2021 to 2/2022. We used an integrated analysis approach combining modified grounded theory and implementation science constructs. Half reported recent injection drug use, and 6 were taking buprenorphine. Mental health symptoms were common, and half described engaging in transactional sex. The majority expressed strong interest in PrEP. Participants reported the app would be highly acceptable for PrEP and MAT adherence support, but only two redeemed the prescription. The most common barriers included phone and internet access. Our findings highlight potential implementation challenges for the use of such an app to support PrEP use in this population. Poor uptake of the app at follow-up indicates that initial prescription redemption is a major barrier to reSET-O implementation.

Reducing the harms of xylazine: clinical approaches, research deficits, and public health context

OBJECTIVES

Xylazine has emerged as a consistent part of the unregulated drug supply in recent months. We discuss major domains of xylazine's harm, current knowledge deficits, clinical and harm reduction strategies for minimizing harm, and xylazine's public health and policy context. As an interdisciplinary team from across the USA, we have pooled our knowledge to provide an overview of xylazine's current and emerging contexts.

METHODS

To inform this essay, the pertinent literature was reviewed, clinical knowledge and protocols were shared by multiple clinicians with direct expertise, and policy and public health context were added by expert authors.

RESULTS

We describe xylazine's major harm domains-acute poisoning, extended sedation, and wounds, along with anemia and hyperglycemia, which have been reported anecdotally but lack as clear of a connection to xylazine. Current successful practices for xylazine wound care are detailed. Understanding xylazine's epidemiology will also require greater investment in drug checking and surveillance. Finally, approaches to community-based wound care are discussed, along with an orientation to the larger policy and public health context.

CONCLUSIONS

Addressing the harms of xylazine requires interdisciplinary participation, investment in community-based harm reduction strategies, and improved drug supply surveillance. The relatively unique context of xylazine demands buy-in from public health professionals, harm reduction professionals, clinicians, basic science researchers, policymakers and more.

"Just another thing for me to stress off of": Responses to unintentional fentanyl use in a community-based study of people who use opioids

The unintentional consumption of fentanyl is a serious health risk for people who use illicit drugs. In an ongoing community-based study regarding polysubstance use among people who use opioids, we found that 17 of 58 (29%) of participants who did not endorse fentanyl use in the past thirty days tested positive for fentanyl during point-of-care urinalysis (UA). This paper describes the reactions and experiences of participants who were informed they had consumed fentanyl unintentionally, as well as how the research team handled the unanticipated occurrence of discordant results. Consistent with other recent studies, we found that people learning of unintentional fentanyl use expressed strong concerns about accidental overdose. It was common for participants to reflect on recent substance use experiences that were atypical and might have involved fentanyl, as well as to examine sources of recent drug purchases. While not all participants were surprised that they had unintentionally consumed fentanyl, all felt that learning their positive results was important due to risk of overdose. Research and medical staff have an opportunity to promote awareness of possible contamination by sharing and discussing UA test results with people who use drugs in non-judgmental manner. In addition to the widely promoted harm reduction strategy of testing drugs with fentanyl test strips, self-administered point-of-care UA, particularly after an unexpected reaction to using a drug, could provide useful information for people buying and using illicit drugs.

Opioid Injection-Associated Bacterial Infections in England, 2002-2021: A Time Series Analysis of Seasonal Variation and the Impact of Coronavirus Disease 2019

BACKGROUND

Bacterial infections cause substantial pain and disability among people who inject drugs. We described time trends in hospital admissions for injecting-related infections in England.

METHODS

We analyzed hospital admissions in England between January 2002 and December 2021. We included patients with infections commonly caused by drug injection, including cutaneous abscesses, cellulitis, endocarditis, or osteomyelitis, and a diagnosis of opioid use disorder. We used Poisson regression to estimate seasonal variation and changes associated with coronavirus disease 2019 (COVID-19) response.

RESULTS

There were 92 303 hospital admissions for injection-associated infections between 2002 and 2021. Eighty-seven percent were skin, soft-tissue, or vascular infections; 72% of patients were male; and the median age increased from 31 years in 2002 to 42 years in 2021. The rate of admissions reduced from 13.97 per day (95% confidence interval [CI], 13.59-14.36) in 2003 to 8.94 (95% CI, 8.64-9.25) in 2011, then increased to 18.91 (95% CI, 18.46-19.36) in 2019. At the introduction of COVID-19 response in March 2020, the rate of injection-associated infections reduced by 35.3% (95% CI, 32.1-38.4). Injection-associated infections were also seasonal; the rate was 1.21 (95% CI, 1.18-1.24) times higher in July than in February.

CONCLUSIONS

This incidence of opioid injection-associated infections varies within years and reduced following COVID-19 response measures. This suggests that social and structural factors such as housing and the degree of social mixing may contribute to the risk of infection, supporting investment in improved social conditions for this population as a means to reduce the burden of injecting-related infections.

HIV risk and prevention among clients of a delivery-based harm reduction service during an HIV outbreak among people who use drugs in northern rural Minnesota, USA

BACKGROUND

Since 2019, multiple HIV outbreaks occurred among people who inject drugs (PWID) in Minnesota. Syringe service programs (SSPs) are evidence-based programs that reduce the spread of HIV. We conducted an assessment of characteristics and HIV risk and prevention among clients of a delivery-based SSP near an HIV outbreak in rural, northern Minnesota.

METHODS

In the fall of 2021, we conducted a cross-sectional survey of clients of a mobile SSP based in Duluth, Minnesota. Survey topics included demographics, drug use, sexual behavior, HIV testing history, and HIV status. We conducted descriptive analyses and used univariate logistic regression to identify correlates of syringe sharing. The analysis was limited to PWID in the last six months.

RESULTS

A total of 125 people were surveyed; 77 (62%) were PWID in the last six months. Among these participants, 52% were female and 50% were homeless. Thirty-two percent reported sharing syringes and 45% reported sharing injecting equipment. Approximately one-half (49%) of participants had been tested for HIV in the past year, and none reported being HIV-positive. Individuals reported low condom usage (88% never used), and 23% of participants reported engaging in some form of transactional sex in the last six months. Incarceration in the last year was associated with sharing syringes (odds ratio = 1.4, 95% confidence interval 1.1-1.8).

CONCLUSION

HIV risk was high among PWID receiving services at this SSP. These data highlight a rural SSP that is engaged with people at risk for HIV and needs additional support to expand harm reduction services.

Impact of safer supply programs on injection practices: client and provider experiences in Ontario, Canada

OBJECTIVES

Fentanyl has contributed to a sharp rise in the toxicity of the unregulated drug supply and fatal overdoses in Canada. It has also changed injection practices. Injection frequency has increased as a result and so has equipment sharing and health-related risks. The aim of this analysis was to explore the impact of safer supply programs on injection practices from the perspective of clients and providers in Ontario, Canada.

METHODS

The data set included qualitative interviews with 52 clients and 21 providers that were conducted between February and October 2021 across four safer supply programs. Interview excerpts discussing injection practices were extracted, screened, coded and then grouped into themes.

RESULTS

We identified three themes, each theme corresponding to a change in injection practices. The first change was a decrease in the amount of fentanyl used and a decrease in injection frequency. The second change involved switching to injecting hydromorphone tablets instead of fentanyl. Finally, the third change was stopping injecting altogether and taking safer supply medications orally.

CONCLUSION

Safer supply programs can contribute to reducing injection-related health risks in addition to overdose risks. More specifically, they have the potential to address disease prevention and health promotion gaps that stand-alone downstream harm reduction interventions cannot address, by working upstream and providing a safer alternative to fentanyl.

"Just another thing for me to stress off of:" Responses to Unintentional Fentanyl Use in a Community-based Study of People who Use Opioids

The unintentional consumption of fentanyl is a serious health risk for people who use illicit drugs. In an ongoing community-based study regarding polysubstance use among people who use opioids, we found that 17 of 58 (29%) of participants who did not endorse fentanyl use in the past thirty days tested positive for fentanyl during point-of-care urinalysis (UA). This paper describes the reactions and experiences of participants who were informed they had consumed fentanyl unintentionally, as well as how the research team handled the unanticipated occurrence of discordant results. Consistent with other recent studies, we found that people learning of unintentional fentanyl use expressed strong concerns about accidental overdose. It was common for participants to reflect on recent substance use experiences that were atypical and might have involved fentanyl, as well as to examine sources of recent drug purchases. While not all participants were surprised that they had unintentionally consumed fentanyl, all felt that learning their positive results was important due to risk of overdose. Research and medical staff who routinely conduct urinalysis have an opportunity to promote awareness of possible contamination by sharing and discussing UA test results with people who use drugs in non-judgmental manner. In addition to the widely promoted harm reduction strategy of testing drugs with fentanyl test strips, self-administered UA, particularly after an unexpected reaction to using a drug, could provide useful information for people buying and using illicit drugs.

The Synthetic Opioid Fentanyl Increases HIV Replication and Chemokine Co-Receptor Expression in Lymphocyte Cell Lines

BACKGROUND

In the United States, the illicit use of synthetic opioids such as fentanyl has led to a serious public health crisis. Synthetic opioids are known to enhance viral replication and to suppress immunologic responses, but their effects on HIV pathogenesis remain unclear. Thus, we examined the impact of fentanyl on HIV-susceptible and HIV-infected cell types.

METHODS

TZM-bl and HIV-infected lymphocyte cells were incubated with fentanyl at varying concentrations. Expression levels of the CXCR4 and CCR5 chemokine receptors and HIV p24 antigen were quantified with ELISA. HIV proviral DNA was quantified using SYBR RT-PCR. Cell viability was detected with the MTT assay. RNAseq was performed to characterize cellular gene regulation in the presence of fentanyl.

RESULTS

Fentanyl enhanced expression of both chemokine receptor levels in a dose-dependent manner in HIV-susceptible and infected cell lines. Similarly, fentanyl induced viral expression in HIV-exposed TZM-bl cells and in HIV-infected lymphocyte cell lines. Multiple genes associated with apoptosis, antiviral/interferon response, chemokine signaling, and NFκB signaling were differentially regulated.

CONCLUSIONS

Synthetic opioid fentanyl impacts HIV replication and chemokine co-receptor expression. Increased virus levels suggest that opioid use may increase the likelihood of transmission and accelerate disease progression.

Patient and Provider Perspectives on a Novel, Low-Threshold HIV PrEP Program for People Who Inject Drugs Experiencing Homelessness

BACKGROUND

HIV outbreaks among people who inject drugs (PWID) and experience homelessness are increasing across the USA. Despite high levels of need, multilevel barriers to accessing antiretroviral pre-exposure prophylaxis (PrEP) for HIV prevention persist for this population. The Boston Health Care for the Homeless Program (BHCHP) initiated a low-threshold, outreach-based program to support engagement in PrEP services among PWID experiencing homelessness.

METHODS

To inform dissemination efforts, we explored patient and provider perspectives on key program components. From March to December 2020, we conducted semi-structured qualitative interviews with current and former BHCHP PrEP program participants and prescribers, patient navigators, and outreach workers (i.e., providers). Thematic analysis explored perspectives on key program components.

RESULTS

Participants (n = 21) and providers (n = 11) identified the following five key components of BHCHP's PrEP program that they perceived to be particularly helpful for supporting patient engagement in PrEP services: (1) community-driven PrEP education; (2) low-threshold, accessible programming including same-day PrEP prescribing; (3) tailored prescribing supports (e.g., on-site pharmacy, short-term prescriptions, medication storage); (4) intensive outreach and navigation; and (5) trusting, respectful patient-provider relationships.

DISCUSSION

Findings suggest that more patient-centered services formed the basis of BHCHP's innovative, successful PrEP program. While contextual challenges including competing public health emergencies and homeless encampment "sweeps" necessitate ongoing programmatic adaptations, lessons from BHCHP's PrEP program can inform PrEP delivery in a range of community-based settings serving this population, including syringe service programs and shelters.

Network Correlates of Using a Syringe After an Injection Partner Among Women Who Inject Drugs in Philadelphia Pennsylvania

This analysis aims to identify relationship-level correlates of receptive syringe sharing among women who inject drugs in Philadelphia. Sixty-four women who injected daily were recruited from Prevention Point Philadelphia's syringe exchange program (9/2/20 - 11/23/20). Interviewer-administered surveys collected (1) individual-level demographics and risk behaviors and (2) relationship-level information about each past-6-month injection partner and injecting practices between the two. We built two separate log-binomial regression models which accounted for clustering of network members within participants to identify relationship-level correlates of using a syringe after a partner. Women reported injecting with a syringe previously used by 21.14% of partners. Women were more likely to use a syringe after sex partners (Adjusted Prevalence Ratio [APR]model_1=2.77) and those who provided injection assistance (APRmodel_1=1.92) or emotional support (APRmodel_2=6.19). Future harm reduction efforts could train women to negotiate safer injection practices with sex partners and those who provide injection assistance and/or emotional support.

A qualitative exploration of unintentional versus intentional exposure to fentanyl among people who use drugs in Austin, TX

BACKGROUND

The prevalence of deaths involving synthetic opioids has historically been lower in Texas than most U.S. states but more than quadrupled from January 2020 to January 2022. This paper explores the emergence of fentanyl in a drug supply where black tar heroin predominates, a factor considered protective against fentanyl adulteration, through the perspectives of people who use drugs (PWUD).

OBJECTIVES

We describe experiences of unintentional exposure to fentanyl, illustrate how some people identify fentanyl in their supply, and present harm reduction strategies that PWUD use to avoid overdose.

METHODS

Thirty rapid assessment interviews were conducted in July 2021 at 2 mobile outreach sites of a harm reduction organization in Austin, Texas. The brief semistructured interviews were designed to assess participant fentanyl exposure experiences.

RESULTS

Participants were clients who reported using heroin or fentanyl in the past week and had lived in Texas for at least 6 months. Seventeen participants identified as male, 10 as female, and 3 as nonbinary. Half identified as white; other participants were Latinx (6), black (2), American Indian (1), and mixed race (6). Two-thirds were unhoused or in transitional housing. The drug supply in Texas has evolved; most participants reported that the heroin and other drugs they obtained contain fentanyl. Participants detected differences by observing changes in the physical characteristics of the drug, experiencing unexpected effects, and using fentanyl test strips. Many had been unintentionally exposed to fentanyl and expressed concerns about fentanyl's presence. The presence of fentanyl had negative unintended consequences for participants, including adverse effects and developing a dependence on opioids.

CONCLUSION

PWUD in Austin, Texas, report increasing prevalence of unintentional fentanyl exposure, despite the predominance of black tar heroin. Pharmacists can provide crucial supplies and education to safeguard the health of this vulnerable population.

Fentanyl enhances HIV infection in vitro

Acquired immunodeficiency syndrome (AIDS) caused by Human immunodeficiency virus type 1 (HIV-1) has a high tendency among illicit drug abusers. Recently, it is reported that abuse of fentanyl, a potent synthetic μ receptor-stimulating opioid, is an independent risk factor for HIV-1 infection. However, the mechanism of action in augmenting HIV-1 infection still remains elusive. In this study, we found that fentanyl enhanced infection of HIV-1 in MT2 cells, primary macrophages and Jurkat C11 cells. Fentanyl up-regulated CXCR4 and CCR5 receptor expression, which facilitated the entry of virion into host cells. In addition, it down-regulated interferon-β (IFN-β) and interferon-stimulated genes (APOBEC3F, APOBEC3G and MxB) expression in MT2 cells. Our findings identify an essential role of fentanyl in the positive regulation of HIV-1 infection via the upregulation of co-receptors (CXCR4/CCR5) and downregulation of IFN-β and ISGs, and it may have an important role in HIV-1 immunopathogenesis.

Prevalence and factors associated with neck injection among people who inject drugs in San Francisco, California

BACKGROUND

Groin and neck injections are generally a last resort for people who inject drugs (PWID) who do not have easy access to functioning veins. These alternative injection practices can lead to an increased likelihood of adverse health outcomes. There is still much we do not know about groin and neck injections among PWID in the US, as the literature to-date comes from studies primarily focused on groin injections outside the US. We assessed prevalence, predictors, and associated behaviors of neck injection through a survey fielded in San Francisco, California, US.

METHODS

The sample comes from a longitudinal observational study that used targeted sampling to recruit PWID in San Francisco. The current study sample includes 239 PWID who completed their 12-month survey between June 2019 and June 2020.

RESULTS

About a third of the sample reported injecting in their neck in the past 30 days, with the most common reason being lack of available veins. Age, past 6-month abscess / soft tissue infection, and past 30-day use of opioids mixed with cocaine were significantly associated with past 30-day neck injection in the final multivariate model. Past 30-day neck injection was also significantly associated with being injected by another person in the past 30 days.

CONCLUSIONS

PWID at higher risk for vein deterioration were more likely to inject into their neck. Harm reduction strategies such as safer injection counseling, safe smoking supplies, use of "street doctors," and safe consumption sites may reduce instances of neck injection and/or associated health risks.

Association of Illicit Fentanyl Use with Injection Risk Practices Among People who Inject Drugs

We investigated the association between fentanyl injection frequency and sharing of injection equipment among people who inject drugs. We surveyed 249 people who inject drugs in Toronto in 2019. We estimated predicted probabilities of associations between fentanyl injection frequency and injection risk practices. In prior 6 months, 117 (47.0%) of participants injected fentanyl daily, 49 (19.7%) less than daily, and 78 (31.3%) did not inject fentanyl. Participants who injected fentanyl daily shared syringes more often than those not injecting fentanyl (25.0% vs. 4.9%; χ² = 11.54, p = 0.0007). Participants who injected fentanyl daily (42.4% vs. 11.3%; χ² = 18.05, p < 0.0001) and less than daily (37.2% vs. 11.3%; χ² = 5.88 p = 0.02) shared cookers more often than those not injecting fentanyl. Participants who injected fentanyl daily (30.2% vs. 9.7%; χ² = 9.05, p = 0.003) and less than daily (30.3% vs. 9.7%; χ² = 4.11, p = 0.04) shared filters more often than those not injecting fentanyl. No differences in probabilities of sharing equipment were detected between participants who injected fentanyl daily and less than daily. People using fentanyl reported injection practices that increased risk for infectious disease transmission.

Long-Acting Injectable Human Immunodeficiency Virus Pre-Exposure Prophylaxis Preferred Over Other Modalities Among People Who Inject Drugs: Findings from a Qualitative Study in California

People who inject drugs (PWID) have extraordinarily low uptake of human immunodeficiency virus (HIV) pre-exposure prophylaxis (PrEP) despite high levels of need. Long-acting PrEP modalities hold promise for HIV prevention among PWID, but product preferences remain poorly understood. From September to November 2021, we conducted qualitative interviews with 28 HIV-negative, adult (≥18 years) PWID in San Diego County, CA, to explore their perspectives on daily oral PrEP pills and long-acting PrEP modalities (i.e., injections, implants, intravaginal rings, and broadly neutralizing antibodies), which we explained using standard scripts. Thematic analysis identified variations in PrEP modality interest and acceptability. We identified three key factors across the 28 interviews that appeared to influence PrEP modality preferences: perceived convenience of use, invasiveness, and familiarity (based on past experience). Overall, most participants preferred injectable PrEP over other modalities because they viewed injectable medications as convenient, noninvasive, and familiar. While injectable PrEP was recently approved for use in the United States and was most the acceptable PrEP modality in this sample, our findings suggest that intervention and implementation research is urgently needed to improve our understanding of strategies that could support access, uptake, and sustained adherence to longer-acting PrEP for PWID.

The introduction of fentanyl on the US-Mexico border: An ethnographic account triangulated with drug checking data from Tijuana

BACKGROUND

Illicitly-manufactured fentanyls (fentanyl) have changed the risk environment of people who use drugs (PWUD). In California and many western US states, the opioid overdose rate spiked from 2016 to 2021, driven largely by fentanyl. Mexican border cities act as transit through-points for the illicit drug supply and similar evolving health risks are likely to be present. Nevertheless, due to data gaps in surveillance infrastructure, little is known about fentanyl prevalence in Mexico.

METHODS

We employ intensive ethnographic participant-observation among PWUD, as well as key informants including harm reduction professionals, EMTs, and physicians on the front lines in Tijuana, Mexico. We triangulate interview data and direct observations of consumption practices with n=652 immunoassay-based fentanyl tests of drug paraphernalia from mobile harm reduction clinics in various points throughout the city.

RESULTS

PWUD informants described a sharp increase in the psychoactive potency and availability of powder heroin-referred to as "china white"-and concomitant increases in frequency of overdose, soft tissue infection, and polysubstance methamphetamine use. Fentanyl positivity was found among 52.8% (95%CI: 48.9-56.6%) of syringes collected at harm reduction spaces, and varied strongly across sites, from 2.7% (0.0-5.7%) to 76.5% (68.2-84.7%), implying strong market heterogeneity. Controlling for location of collection, syringe-based fentanyl positivity increased by 21.7% (10.1-42.3%) during eight months of testing. Key informants confirm numerous increased public health risks from fentanyl and describe the absence of a systematic or evidence-based governmental response; naloxone remains difficult to access and recent austerity measures have cut funding for harm reduction in Mexico.

CONCLUSIONS

Fentanyl, linked to powder heroin, is changing the risk environment of PWUD on the US-Mexico border. Improved surveillance is needed to track the evolving street drug supply in Mexico and related health impacts for vulnerable populations. Structural factors limiting access to naloxone, harm reduction, substance use treatment, and healthcare, and minimal overdose surveillance, must be improved to provide an effective systemic response.

Severe bacterial infections in people who inject drugs: the role of injection-related tissue damage

Background

In the context of the current U.S. injection drug use epidemic, targeted public health harm reduction strategies have traditionally focused on overdose prevention and reducing transmission of blood-borne viral infections. Severe bacterial infections (SBI) associated with intravenous drug use have been increasing in frequency in the U.S. over the last decade. This qualitative study aims to identify the risk factors associated with SBI in hospitalized individuals with recent injection drug use.

Methods

Qualitative analysis (n = 15) was performed using an in-depth, semi-structured interview of participants admitted to Bellevue Hospital, NYC, with SBI and recent history of injection drug use. Participants were identified through a referral from either the Infectious Diseases or Addition Medicine consultative services. Interviews were transcribed, descriptively coded, and analyzed for key themes.

Results

Participants reported a basic understanding of prevention of blood-borne viral transmission but limited understanding of SBI risk. Participants described engagement in high risk injection behaviors prior to hospitalization with SBI. These practices included polysubstance use, repetitive tissue damage, nonsterile drug diluting water and multipurpose use of water container, lack of hand and skin hygiene, re-use of injection equipment, network sharing, and structural factors leading to an unstable drug injection environment. Qualitative analysis led to the proposal of an Ecosocial understanding of SBI risk, detailing the multi-level interplay between individuals and their social and physical environments in producing risk for negative health outcomes.

Conclusions

Structural factors and injection drug use networks directly impact drug use, injection drug use practices, and harm reduction knowledge, ultimately resulting in tissue damage and inoculation of bacteria into the host and subsequent development of SBI. Effective healthcare and community prevention efforts targeted toward reducing risk of bacterial infections could prevent long-term hospitalizations, decrease health care expenditures, and reduce morbidity and mortality.

Health risk associated with residential relocation among people who inject drugs in Los Angeles and San Francisco, CA: a cross sectional study

Background

Given the housing instability and frequent residential relocation (both volitional and hegemonic) of people who inject drugs, we sought to determine whether residential relocation (defined as sleeping in a different place in the past 30 days) is associated with health outcomes in a sample of people who inject drugs (PWID).

Methods

We recruited 601 PWID using targeted sampling and interviewed them between 2016 and 2018 in San Francisco and Los Angeles, CA about housing, drug use practices, and service utilization. We then developed multivariable regression models to investigate how residential relocation is associated with violence, health outcomes, and social service access. We analyzed our data between June 2018 and October 2019.

Results

Participants who relocated in the past 30 days had lower odds of being in substance use treatment (Adjusted Odds Ratio [AOR] = 0.62, 95% Confidence Interval [CI] = 0.42, 0.89) and higher odds of nonfatal overdose (AOR = 2.50, CI = 1.28, 4.90), receptive syringe sharing (AOR = 2.26, CI = 1.18, 4.32), severe food insecurity (AOR = 1.69, CI = 1.14, 2.50), having belongings stolen (AOR = 2.14, CI = 1.42, 3.21), experiencing physical assault (AOR = 1.58, CI = 1.03, 2.43), arrest (AOR = 1.64, CI = 1.02, 2.65), and jail (AOR = 1.90, CI = 1.16, 3.13) in the past 6 months when compared to those who did not relocate.

Conclusions

PWID who have relocated in the past 30 days have higher odds of experiencing violence and life- threatening adverse outcomes, and policies that disrupt living circumstances of PWID should be ended in favor of those that support housing stability.

Six Moments of Infection Prevention in Injection Drug Use: An Educational Toolkit for Clinicians

BACKGROUND

Injection drug use-associated bacterial and viral infections are increasing. Expanding access to harm reduction services, such as safe injection education, are effective prevention strategies. However, these strategies have had limited uptake. New tools are needed to improve provider capacity to facilitate dissemination of these evidence-based interventions.

METHODS

The "Six Moments of Infection Prevention in Injection Drug Use" provider educational tool was developed using a global, rather than pathogen-specific, infection prevention framework, highlighting the prevention of invasive bacterial and fungal infections in additional to viral pathogens. The tool's effectiveness was tested using a short, paired pre/post survey that assessed provider knowledge and attitudes about harm reduction.

RESULTS

Seventy-five respondents completed the paired surveys. At baseline, 17 respondents (22.6%) indicated that they had received no prior training in harm reduction and 28 (37.3%) reported discomfort counseling people who inject drugs (PWID). Sixty respondents (80.0%) reported they had never referred a patient to a syringe service program (SSP); of those, 73.3% cited lack of knowledge regarding locations of SSPs and 40.0% reported not knowing where to access information regarding SSPs. After the training, 66 (88.0%) reported that they felt more comfortable educating PWID (P < .0001), 65 respondents (86.6%) reported they planned to use the Six Moments model in their own practice, and 100% said they would consider referring patients to an SSP in the future.

CONCLUSIONS

The Six Moments model emphasizes the importance of a global approach to infection prevention and harm reduction. This educational intervention can be used as part of a bundle of implementation strategies to reduce morbidity and mortality in PWID.

Factors Associated with Likelihood of Initiating Others into Injection Drug Use Among People Who Inject Drugs in West Virginia

People who inject drugs (PWID) play a critical role in injection-naïve individuals transitioning to injection drug use. We investigated factors associated with future likelihood of initiating injection-naïve individuals using multivariable logistic regression among 418 PWID in rural Appalachia (Cabell County, West Virginia). Less than 10% reported they were likely to initiate someone in the future. Acquiring syringes from a syringe services program was associated with decreased odds of being likely to initiate someone in the future (adjusted odds ratio [aOR] 0.46, 95% CI 0.23, 0.95), while having previously initiated someone into injection drug use was associated with increased odds (aOR 8.65, 95% CI 4.07, 18.41). Among our sample of PWID in Appalachia, a small proportion reported that they would be likely to initiate an injection-naïve individual in the future. Efforts to reduce injection initiation assistance should focus on this subpopulation of PWID who indicate a willingness to engage in this behavior.

HIV Risk Among Urban and Suburban People Who Inject Drugs: Elevated Risk Among Fentanyl and Cocaine Injectors in Maryland

Drug overdose remains a leading cause of death in the US, with growing rates attributable to illicit fentanyl use. Recent HIV outbreaks among people who inject drugs (PWID) and service disruptions from COVID-19 have renewed concerns on HIV resurgence. We examined the relationship between fentanyl use and three injection-related HIV risk behaviors among PWID in Baltimore City (BC) and Anne Arundel Country (AAC), Maryland. PWID (N = 283) were recruited to the study through targeted sampling at street-based locations in BC and AAC from July 2018 to March 2020. Receptive syringe sharing (RSS) [adjusted odds ratio (AOR): 2.8, 95% confidence interval (CI): 1.2–6.3] and daily injecting (AOR: 1.9, 95% CI: 1.0–3.6) were associated with injecting fentanyl and cocaine together. Fentanyl availability and COVID-19 bring new HIV prevention challenges, particularly among those who inject fentanyl with cocaine, highlighting the importance to expand and sustain harm reduction, prevention, and treatment services for PWID to reduce HIV and overdose burden.

Harm Reduction in Health Care Settings

Harm reduction is an approach to reduce the risk of harms to an individual using substances without requiring abstinence. This review discusses substance-specific interventions for opioids, alcohol, and stimulants that can minimize harms for individuals who use these substances. Topics discussed include overdose prevention, infection prevention, and low-barrier substance use disorder treatment.

Growing racial/ethnic disparities in overdose mortality before and during the COVID-19 pandemic in California

As overdose mortality is spiking during the COVID-19 pandemic, few race/ethnicity-stratified trends are available. This is of particular concern as overdose mortality was increasing most rapidly in Black and Latinx communities prior to the pandemic. We used quarterly, age-standardized overdose mortality rates from California to assess trends by race/ethnicity and drug involved over time. Rates from 2020 Q2-Q4 were compared to expected trends based on ARIMA forecasting models fit using data from 2006 to 2020 Q1. In 2020 Q2-Q4 overdose death rates rose by 49.8% from 2019, exceeding an expected increase of 11.5% (95%CI: 0.5%-22.5%). Rates significantly exceeded forecasted trends for all racial/ethnic groups. Black/African American individuals saw an increase of 52.4% from 2019, compared to 42.6% among their White counterparts. The absolute Black-White overdose mortality gap rose from 0.7 higher per 100,000 for Black individuals in 2018 to 4.8 in 2019, and further increased to 9.9 during the pandemic. Black overdose mortality in California was therefore 34.3% higher than that of White individuals in 2020 Q2-Q4. This reflects growing methamphetamine-, cocaine-, and fentanyl-involved deaths among Black communities. Growing racial disparities in overdose must be understood in the context of the unequal social and economic fallout from the COVID-19 pandemic, during which time Black communities have been subjected to the dual burden of disproportionate COVID-19 deaths and rising overdose mortality. Increased investments are required to ameliorate racial/ethnic disparities in substance use treatment, harm reduction, and the structural drivers of overdose, as part of the COVID-19 response and post-pandemic recovery efforts.

Against Medical Advice Discharges in Injection and Non-injection Drug Use-associated Infective Endocarditis: A Nationwide Cohort Study

BACKGROUND

Among those with injection drug use-associated infective endocarditis (IDU-IE), against medical advice (AMA) discharge is common and linked to adverse outcomes. Understanding trends, risk factors, and timing is needed to reduce IDU-IE AMA discharges.

METHODS

We identified individuals ages 18-64 with International Classification of Diseases, 9thRevision, diagnosis codes for infective endocarditis (IE) in the National Inpatient Sample, a representative sample of United States hospitalizations from January 2010 to September 2015. We plotted unadjusted quarter-year trends for AMA discharges and used multivariable logistic regression to identify factors associated with AMA discharge among IE hospitalizations, comparing IDU-IE with non-IDU-IE.

RESULTS

We identified 7259 IDU-IE and 23 633 non-IDU-IE hospitalizations. Of these hospitalizations, 14.2% of IDU-IE and 1.9% of non-IDU-IE resulted in AMA discharges. More than 30% of AMA discharges for both groups occurred before hospital day 3. In adjusted models, IDU status (adjusted odds ratio [AOR], 3.92; 95% confidence interval [CI], 3.43-4.48)] was associated with increased odds of AMA discharge. Among IDU-IE, women (AOR, 1.21; 95% CI, 1.04-1.41) and Hispanics (AOR, 1.32; 95% CI, 1.03-1.69) had increased odds of AMA discharge, which differed from non-IDU-IE. Over nearly 6 years, odds of AMA discharge increased 12% per year for IDU-IE (AOR, 1.12; 95% CI, 1.07-1.18) and 6% per year for non-IDU-IE (AOR, 1.06; 95% CI. 1.00-1.13).

CONCLUSIONS

AMA discharges have risen among individuals with IDU-IE and non-IDE-IE. Among those who inject drugs, AMA discharges were more common and increases sharper. Efforts that address the rising fraction, disparities, and timing of IDU-IE AMA discharges are needed.

Buprenorphine/naloxone associated with a reduced odds of fentanyl exposure among a cohort of people who use drugs in Vancouver, Canada

BACKGROUND

Little is known about the relationship between opioid agonist therapy (OAT) and fentanyl use, specifically. This study aimed to estimate the association between current use of different forms of OAT, including methadone, buprenorphine/naloxone (BUP/NX), slow release oral morphine (SROM), or injectable opioid agonist treatment (iOAT), and the likelihood of a fentanyl-positive urine drug test (UDT) as compared to no OAT.

METHODS

Data were obtained from three community-recruited prospective cohort studies of people who use drugs in Vancouver, Canada from December 2016 through November 2018. Using multivariable Generalized Estimating Equations (GEE), we examined the association between current use of each form of OAT, as compared to no OAT, and fentanyl-positive UDT among participants who use opioids.

RESULTS

The 915 participants contributed 2112 UDTs over a median of two follow-up visits. The majority of UDTs (74.9 %) were positive for fentanyl. After adjustment for a priori defined confounding factors, compared to no OAT, current use of BUP/NX was associated with lower odds of fentanyl-positive UDT (odds ratio [OR] = 0.36, 95 % confidence interval [CI]: 0.22-0.58) while current use of methadone (OR = 0.84, 95 % CI: 0.65-1.07), iOAT (OR = 1.30, 95 % CI: 0.75-2.28), and SROM (OR = 1.34, 95 % CI: 0.74-2.43) were not.

CONCLUSIONS

In this cohort of people who use opioids in Vancouver, only use of BUP/NX was associated with lower odds of fentanyl-positive UDT. Our findings highlight high rates of ongoing fentanyl use despite the use of OAT and support the expansion of BUP/NX for the treatment of people who use fentanyl.

Trends in Hospitalizations for Serious Infections Among People With Opioid Use Disorder in Ontario, Canada

Opioid use among people who inject drugs can lead to serious complications, including infections. We sought to study trends in rates of these complications among people with an opioid use disorder (OUD) and the sequelae of those hospitalizations.

Novel chimeric monoclonal antibodies that block fentanyl effects and alter fentanyl biodistribution in mice

The prevalence and societal impact of opioid use disorder (OUD) is an acknowledged public health crisis that is further aggravated by the current pandemic. One of the devastating consequences of OUD is opioid overdose deaths. While multiple medications are now available to treat OUD, given the prevalence and societal burden, additional well-tolerated and effective therapies are still needed. To this point, we have developed chimeric monoclonal antibodies (mAb) that will specifically complex with fentanyl and its analogs in the periphery, thereby preventing them from reaching the central nervous system. Additionally, mAb-based passive immunotherapy offers a high degree of specificity to drugs of abuse and does not interfere with an individual’s ability to use any of the medications used to treat OUD. We hypothesized that sequestering fentanyl and its analogs in the periphery will mitigate their negative effects on the brain and peripheral organs. This study is the first report of chimeric mAb against fentanyl and its analogs. We have discovered, engineered the chimeric versions, and identified the selectivity of these antibodies, through in vitro characterization and in vivo animal challenge studies. Two mAb candidates with very high (0.1–1.3 nM) binding affinities to fentanyl and its analogs were found to be effective in engaging fentanyl in the periphery and blocking its effects in challenged animals. Results presented in this work constitute a major contribution in the field of novel therapeutics targeting OUD.

Consuming illicit opioids during a drug overdose epidemic: Illicit fentanyls, drug discernment, and the radical transformation of the illicit opioid market

BACKGROUND

North America continues to face an opioid overdose epidemic, driven by persistent increases in illicit fentanyls and fluctuations in potency leading to uncertainty for consumers. This qualitative study was conducted to better understand how people who inject drugs (PWID) came to recognize fentanyl as a growing adulterant of heroin and the subsequent sensory discernment strategies they employed to continue injecting. Our main objective was to investigate how observations and knowledge are combined as homegrown techniques for detecting fentanyl and minimizing risk. Secondary objectives were to examine the impact of growing fentanyl adulteration on individual drug use behavior.

METHODS

Between April and May 2019, 28 PWID (18 men, 10 women; average age = 38.43 years, SD = 9.26) were purposely recruited from a needle services program in Greensboro, North Carolina. Study participants were interviewed in-person using a qualitative, semi-structured instrument. Interviews were analyzed with a general inductive approach using NVivo12.

RESULTS

Participants described methods for detecting fentanyl in illicit opioids. Sudden increases in the potency of the 'rush' and sharp decreases in the length of the 'high' were chief indicators along with changes in drug color and texture. Heavy sedation was associated with fentanyl use and histamine-releasing effects characterized as 'pins and needles' were ascribed to injecting fentanyl as a component of the rush. Fentanyl's short high helped explain higher injection frequency and heavy sedation was the leading reason for co-using fentanyl with cocaine/crack or methamphetamine.

CONCLUSION

PWID have the capacity to recognize changes to the illicit opioid supply. Study participants navigated unpredictable fluctuations in the illicit opioid market by employing homegrown discernment techniques, modifying drug use behavior, and co-using non-opioid drugs. Researchers and policymakers should involve PWID as subject matter experts to help modernize harm reduction for the fentanyl age with practical strategies to boost resiliency and save lives.

Transition from injecting opioids to smoking fentanyl in San Francisco, California

BACKGROUND

The introduction of illicitly made fentanyl in the United States has slowly replaced heroin. New illicit drugs are often associated with changes in frequency and modes of administration. We assessed changes in injection frequency and smoking fentanyl in the new era of fentanyl availability in San Francisco.

METHODS

We used targeted sampling to recruit 395 people who inject drugs (PWID) into an observational cohort study in San Francisco 2018-2020. We assessed changes in injection frequency, opioid injection frequency and fentanyl smoking frequency in four six-month periods. We also conducted qualitative interviews with PWID asking about motivations for injecting and smoking opioids.

RESULTS

The median number of past-month injections steadily decreased by semi-annual calendar year from 92 injections in July to December 2018 to 17 injections in January to June 2020. The rate of opioid injections reduced by half (Adjusted Incidence Rate Ratio = 0.41; 95 % Confidence Interval = 0.25, 0.70; p < 0.01). The number of days smoking fentanyl was associated with fewer number of injections (X2(2) = 11.0; p < 0.01). Qualitative interviews revealed that PWID's motivation for switching from injecting tar heroin to smoking fentanyl was related to difficulties accessing veins. After switching to smoking fentanyl, they noticed many benefits including how the drug felt, improved health, fewer financial constraints, and reduced stigma.

CONCLUSION

Between 2018 and 2020, there was a shift from injecting tar heroin to smoking fentanyl in San Francisco. Reductions in injection of illicit drugs may offer public health benefit if it reduces risk of blood-borne viruses, abscesses and soft-tissue infections, and infective endocarditis.

Syringe Coverage Among People Who Inject Drugs in West Virginia, USA

Ensuring people who inject drugs (PWID) have ≥ 100% sterile syringe coverage (i.e., persons have access to a sterile syringe for all injections) is optimal for HIV prevention. Existing syringe coverage literature is informative, yet little work has examined syringe coverage among PWID in rural communities. Using data from a 2018 PWID population estimation study conducted in a rural county in West Virginia, we used logistic regression to identify correlates of adequate sterile syringe coverage (at least 100%). A minority (37%) of PWID reported having adequate syringe coverage. Factors inversely associated with adequate syringe coverage included having recently (past 6 months): engaged in transactional sex work, shared syringes, and injected fentanyl. Having exclusively acquired syringes from a syringe services program was associated with increased odds of adequate syringe coverage. Rural PWID may benefit from tailored interventions designed to increase sterile syringe access.

Utilising an access to care integrated framework to explore the perceptions of hepatitis C treatment of hospital-based interventions among people who use drugs

BACKGROUND

Gaps remain in the hepatitis C virus (HCV) care cascade for people who use drugs (PWUD). Acute medical or surgical illnesses requiring hospitalisation are an opportunity to address addiction, but how inpatient strategies could affect HCV care accessibility for PWUD remains unknown. We explored patient perspectives of hospital-based interventions using an integrated framework of access to HCV care.

METHODS

We conducted a qualitative study of hospitalised adults (n=27) with HCV and addiction admitted to an urban academic medical centre in the United States between June and November 2019. Individual interviews were audio-recorded, transcribed, and dual-coded. We analysed data with coding specific for hospital-based interventions including screening, conducting HCV-related laboratory work-up, starting treatment, connecting with peers, and coordinating outpatient care. We analysed coded data at the semantic level for emergent themes using a framework approach based off an integrated framework of access to HCV care.

RESULTS

The majority of participants primarily used opioids (78%), were white (85%) and men (67%). Participants frequently reported HCV screening during previous hospitalisation with rare inpatient connection to HCV-related services. Participants expressed willingness to discuss HCV treatment candidacy during hospitalisation; however, lack of inpatient conversations led to perception that "nothing could be done" during admission. Participants expressed interest in completing inpatient HCV work-up to "get the ball rollin'" - consolidating care would enhance outpatient service permeability by reducing barriers. Others resisted HCV care coordination, preferring to focus on "immediate" issues including health conditions and addiction treatment. Participants also expressed openness to engaging with peers about HCV, noting shared drug use experience as critical to a peer relationship when discussing HCV.

CONCLUSION

Hospitalised PWUD have varied priorities, necessitating adaptable interventions for addressing HCV. Hospitalisation can be an opportunity to address HCV access to care including identification of treatment eligibility, consolidation of care, and facilitation of HCV-related referrals.

Social and structural determinants of injecting-related bacterial and fungal infections among people who inject drugs: protocol for a mixed studies systematic review

INTRODUCTION

Injecting-related bacterial and fungal infections are a common complication among people who inject drugs (PWID), associated with significant morbidity and mortality. Invasive infections, including infective endocarditis, appear to be increasing in incidence. To date, preventive efforts have focused on modifying individual-level risk behaviours (eg, hand-washing and skin-cleaning) without much success in reducing the population-level impact of these infections. Learning from successes in HIV prevention, there may be great value in looking beyond individual-level risk behaviours to the social determinants of health. Specifically, the risk environment conceptual framework identifies how social, physical, economic and political environmental factors facilitate and constrain individual behaviour, and therefore influence health outcomes. Understanding the social and structural determinants of injecting-related bacterial and fungal infections could help to identify new targets for prevention efforts in the face of increasing incidence of severe disease.

METHODS AND ANALYSIS

This is a protocol for a systematic review. We will review studies of PWID and investigate associations between risk factors (both individual-level and social/structural-level) and the incidence of hospitalisation or death due to injecting-related bacterial infections (skin and soft-tissue infections, bacteraemia, infective endocarditis, osteomyelitis, septic arthritis, epidural abscess and others). We will include quantitative, qualitative and mixed methods studies. Using directed content analysis, we will code risk factors for these infection-related outcomes according to their contributions to the risk environment in type (social, physical, economic or political) and level (microenvironmental or macroenvironmental). We will also code and present risk factors at each stage in the process of drug acquisition, preparation, injection, superficial infection care, severe infection care or hospitalisation, and outcomes after infection or hospital discharge.

ETHICS AND DISSEMINATION

As an analysis of the published literature, no ethics approval is required. The findings will inform a research agenda to develop and implement social/structural interventions aimed at reducing the burden of disease.

PROSPERO REGISTRATION NUMBER

CRD42021231411.

The naloxone delivery cascade: Identifying disparities in access to naloxone among people who inject drugs in Los Angeles and San Francisco, CA

BACKGROUND

Opioid overdoses are a leading cause of injury death in the United States. Providing people who inject drugs (PWID) with naloxone is essential to preventing deaths. However, research regarding gaps in naloxone delivery is limited.

METHODS

We interviewed 536 PWID in San Francisco and Los Angeles, California from 2017 to 2018. We described naloxone engagement and re-engagement cascades, and identified factors associated with receiving naloxone in the past six months and currently owning naloxone.

RESULTS

The engagement cascade showed 72 % of PWID ever received naloxone, 49 % received it in the past six months, and 35 % currently owned naloxone. The re-engagement cascade showed, among PWID who received naloxone in the past six months, 74 % used and/or lost naloxone, and 67 % refilled naloxone. In multivariable analyses, identifying as Latinx (aRR = 0.53; 95 % CI: 0.39, 0.72) and Black (aRR = 0.73; 95 % CI: 0.57, 0.94) vs White were negatively associated with receiving naloxone in the past six months, while using opioids 1-29 times (aRR = 1.35; 95 % CI: 1.04, 1.75) and 30+ times (aRR = 1.52; 95 % CI: 1.17, 1.99) vs zero times in the past 30 days and witnessing an overdose in the past six months (aRR = 1.69; 95 % CI: 1.37, 2.08) were positively associated with receiving naloxone in the past six months. In multivariable analyses, being unhoused vs housed (aRR = 0.82; 95 % CI: 0.68, 0.99) was negatively associated with currently owning naloxone.

CONCLUSIONS

Our study adds to the literature by developing naloxone engagement and re-engagement cascades to identify disparities. Naloxone scale-up should engage populations facing inequitable access, including people of color and those experiencing homelessness.

Association of skin infections with sharing of injection drug preparation equipment among people who inject drugs

BACKGROUND

Sharing needles and injection drug preparation equipment (IDPE) among people who inject drugs (PWID) are well-established risk factors for viral transmission. Shared needles and IDPE may serve as bacterial niduses for skin and soft tissue infections (SSTI). Given the rising rates of SSTI in PWID, we investigated the association of needle and IDPE sharing on incidence of SSTI in a cohort of PWID.

METHODS

Inpatient PWID (N = 252) were recruited to a randomized controlled trial of an intervention aimed at reducing infections. The primary outcome was self-reported incidence of SSTI one-year post-hospitalization. In this secondary analysis, we assessed two variables: 1) sharing of IDPE alone, 2) sharing needles with or without IDPE, and compared these groups separately to persons who reported no sharing of needles or IDPE via a mixed-effects negative binomial regression model to estimate the effect of baseline sharing behavior on SSTI during follow-up via incidence rate ratios (IRR).

RESULTS

Participant characteristics: 38 years [mean], 58% male, 60% White, 90% primarily injected opioids, 1.58 (± 2.35) mean SSTI in the year prior to baseline. In terms of sharing behavior, 29% didn't share needles or IDPE, 13% shared IDPE only, and 58% shared needles with or without IDPE three months prior to baseline. After adjusting for co-variables, PWID who shared IDPE alone had a 2.2 fold higher IRR of SSTI (95%CI 1.27; 3.85, p = 0.005) and PWID who shared needles with or without IDPE had a 3.31 fold higher IRR of SSTI (95%CI 2.04; 5.37, p < 0.001), compared to those who did not share any equipment. The number of SSTI at baseline was associated with an IRR of 1.20 of SSTI during follow-up (95%CI 1.09; 1.32, p < 0.001).

CONCLUSIONS

In this cohort of hospitalized PWID, we found a significant association between baseline sharing of IDPE alone and of sharing of needles with or without IDPE with one-year incidence of SSTI.

Barriers and Motivators to Opioid Treatment Among Suburban Women Who Are Pregnant and Mothers in Caregiver Roles

Women of childbearing age who misuse opioids are a particularly vulnerable population, and their barriers to treatment are unique because of their caregiver roles. Research on treatment for opioid use generally draws from urban and rural areas. This study fills a gap in research that focuses on barriers and motivators to opioid treatment in suburban areas. The aim of this study was to give voice to suburban pregnant women and mothers caring for children while using opioids. Ethnographic methods were used for recruitment, and 58 in-depth interviews were analyzed using a modified grounded theory approach. Barriers to medication-assisted treatment (MAT) included stigma, staff attitudes, and perceptions the women had about MAT treatment. Barriers associated with all types of treatment included structural factors and access difficulties. Relationships with partners, friends, family, and providers could be barriers as well as motivators, depending on the social context of the women’s situation. Our findings suggest increasing treatment-seeking motivators for mothers and pregnant women by identifying lack of resources, more empathetic consideration of social environments, and implementing structural changes to overcome barriers. Findings provide a contemporary understanding of how suburban landscapes affect mothers’ treatment-seeking for opioid dependence and suggest the need for more focus on emotional and structural resources rather than strict surveillance of women with opioid dependence who are pregnant or caring for children.

Bivalent Conjugate Vaccine Induces Dual Immunogenic Response That Attenuates Heroin and Fentanyl Effects in Mice

Opioid use disorders and fatal overdose due to consumption of fentanyl-laced heroin remain a major public health menace in the United States. Vaccination may serve as a promising potential remedy to combat accidental overdose and to mitigate the abuse potential of opioids. We previously reported the heroin and fentanyl monovalent vaccines carrying, respectively, a heroin hapten, 6-AmHap, and a fentanyl hapten, para-AmFenHap, conjugated to tetanus toxoid (TT). Herein, we describe the mixing of these antigens to formulate a bivalent vaccine adjuvanted with liposomes containing monophosphoryl lipid A (MPLA) adsorbed on aluminum hydroxide. Immunization of mice with the bivalent vaccine resulted in IgG titers of >10⁵ against both haptens. The polyclonal sera bound heroin, 6-acetylmorphine, morphine, and fentanyl with dissociation constants (K_d) of 0.25 to 0.50 nM. Mice were protected from the anti-nociceptive effects of heroin, fentanyl, and heroin +9% (w/w) fentanyl. No cross-reactivity to methadone and buprenorphine was observed in vivo. Naloxone remained efficacious in immunized mice. These results highlighted the potential of combining TT-6-AmHap and TT-para-AmFenHap to yield an efficacious bivalent vaccine that could ablate heroin and fentanyl effects. This vaccine warrants further testing to establish its potential translatability to humans.