People who inject drugs (PWID) account for the majority of hepatitis C virus (HCV) infections in the United States. The injection-equipment-sharing network likely plays an important role in shaping the dynamics of HCV transmission. Recognizing the emerging HCV epidemic in rural communities, we developed an agent-based network simulation model of HCV transmission via injection equipment sharing and used data on rural PWID networks to inform model parameterization and calibration. We then simulated an array of networks that varied key network properties to understand their impact on the magnitude and distribution of HCV incidence. The results show substantial heterogeneity in HCV acquisition risks across the network, summarized using the Gini coefficient. In addition, although PWID with fewer injection partners had lower incidence, they collectively acquired more infections due to their larger population size. Higher prevalence, average number of partners, and homophily in HCV infection were associated with lower heterogeneity in infection risk across the network and higher overall incidence; other network properties including population size did not have a substantial impact. Our findings illustrate the heterogeneity of HCV transmission among PWID and suggest key network properties that could be measured, evaluated, or considered in the design of interventions for PWID in future studies.

AIMS:This study assessed long-term healthcare resource utilization (HCRU) and direct medical costs associated with COVID-19 among adults and children in the United States. Using a large national claims database, we quantified the incremental healthcare burden during the year following a first COVID-19 diagnosis compared to matched controls without a COVID-19 diagnosis. MATERIALS AND METHODS:This retrospective cohort study used data from the IQVIA PharMetrics Plus database. Patients with a COVID-19 diagnosis (U07.1) between June 1 and November 30, 2022, were matched 1:1 to non-COVID-19 controls based on age, sex, region, insurance type, Charlson Comorbidity Index, and baseline HCRU. Outcomes were HCRU and all-cause healthcare costs accrued during the post-acute period (≥31 days after first COVID-19 diagnosis), measured cumulatively through 1, 3, 6, 9, and 11 months of follow-up. Generalized linear models estimated cost ratios. RESULTS:The study included 944,627 patients with a COVID-19 diagnosis (U07.1) and an equal number of matched controls. Compared with matched controls, mean total costs during 11 months of post-acute follow-up were 27% higher among adults ($11,508 vs $9,040; p < 0.001) and 42% higher among pediatric patients with COVID-19 ($3,997 vs $2,812; p < 0.001). Costs were higher for COVID-19 cases at all follow-up time points. Among adults at the 11-month follow-up time, costs increased with acute infection severity, with mean costs of $10,372 for outpatients, $36,848 for hospitalized patients, and $51,643 for ICU patients, compared with $8,617, $16,926, and $17,620, respectively, among matched controls (all p < 0.001). Among adults, cost ratios peaked at 1 month of follow-up (1.32; 95% CI: 1.31-1.33) and declined to 1.15 (95% CI: 1.14-1.15) at 11 months. CONCLUSIONS:There were significantly higher post-acute HCRU and costs among both adults and pediatrics with a COVID-19 diagnosis compared to matched controls without one, with elevated cost differences persisting up to 12 months post-infection.

OBJECTIVES:To assess the cost-effectiveness, public health impact, and budget impact of receiving the LP.8.1-adapted Pfizer-BioNTech COVID-19 Vaccine among United States adults aged ≥ 18 years. METHODS:A previously published economic model was adapted to compare receiving the LP.8.1-adapted Pfizer-BioNTech COVID-19 Vaccine (2025/2026 formula) versus not in adults aged 18-64 years at high risk of severe COVID-19 and all adults aged ≥ 65 years. Age-specific epidemiological inputs were derived from public health surveillance data. Clinical, cost, and vaccine effectiveness parameters were informed by published literature. The budget impact analysis was based on a hypothetical 1-million-member plan and used a payer perspective. RESULTS:Without vaccination, the model projected 41.5 million new symptomatic cases, 43,681 deaths, 338,252 hospitalizations, $80 billion in total costs, and 1.99 million QALYs lost among adults aged ≥18 years, with the greatest health burden observed among adults aged ≥65 years (73% of hospitalizations and 83% of deaths) and the greatest economic burden in adults aged 18 to 64 years at high risk of severe outcomes (62% of total costs). Compared to no vaccination, vaccination with the LP.8.1-adapted Pfizer-BioNTech COVID-19 vaccine (2025/2026 formula) in the populations aged 18 to 64 years and ≥18 years, respectively was projected to prevent 212,096 and 620,333 cases, 137 and 1,867 deaths, and 1,501 and 12,677 hospitalizations, resulting in incremental costs of $1.1 billion and $567 million, 2,411 and 15,430 LYs gained, 70,493 and 181,137 QALYs gained, ICERs of $16,238 and $3,137 from the societal perspective and $34,022 and $8,059 from the payer perspective. In the budget impact analysis from the payer perspective, vaccination was estimated to result in a modest budget increase. CONCLUSIONS:Vaccinating adults at high risk of severe COVID-19 with the LP.8.1-adapted Pfizer BioNTech COVID-19 Vaccine is projected to be a cost-saving measure from the societal perspective that could reduce the public health and economic burden of COVID-19.

In the United States (US), sexual and gender minority (SGM) people of color (POC) are disproportionately impacted by HIV. Persisting new diagnoses in SGM POC make it unlikely that the US will meet the Ending the HIV Epidemic’s (EHE) goal to reduce new HIV diagnoses by 90% by 2030. Innovative strategies are needed to address this challenge, particularly in the US South, where Black/African American and Latine SGM are disproportionately impacted by HIV. Social network approaches have led to increased HIV testing uptake. Social network interventions that are responsive to SGM POC individuals’ needs could also increase engagement across the HIV prevention and care continuum. This hybrid Type 1 effectiveness-implementation study will evaluate an enhanced Social Network Strategy (eSNS) intervention designed to increase engagement in HIV services (HIV testing, pre-exposure prophylaxis [PrEP] use, and HIV care) among SGM POC. From 2025-2027, eSNS will be delivered in the Charlotte, North Carolina (NC) region, which includes Mecklenburg County, a priority EHE jurisdiction. Phase 1 of the study was a formative period of mixed methods data collection to operationalize enhancements to the Centers for Disease Control and Prevention’s Social Network Strategy (SNS), which will address key facilitators and modifiable barriers to engaging SGM POC in HIV services. In Phase 2, the intervention will be integrated into standard NC Partner Services for people diagnosed with HIV and their sexual and/or social contacts. We will identify network recruiters (Ambassadors) among SGM POC who are either reached by study team members (DIS Coaches) performing Partner Services or referred at community sites. DIS Coaches will guide Ambassadors to identify and refer people in their network (Peers) for HIV services and will support each Ambassador over 2-6 weeks to facilitate Ambassadors’ peer outreach and Peers’ referrals to HIV services. Finally, the study’s Phase 3 will evaluate the eSNS’s effectiveness in increasing HIV services uptake compared to standard-of-care Partner Services in the Raleigh, NC region. This project was funded by the National Institutes of Health and initially approved by the University of North Carolina at Chapel Hill’s Institutional Review Board in 2022. Phase 1 concluded in August 2024. Implementation of eSNS (Phase 2) will launch in January 2025. Evaluation measures (Phase 3) will be assessed at 6-month intervals during and after eSNS implementation. Based on Phase 1 findings, the study was modified to include Latine SGM as Ambassadors and expand identification of Ambassadors through community sites. Substantial reductions in new HIV diagnoses depend on public health approaches that effectively reach people with a higher likelihood of acquiring HIV. Our protocol proposes integrating existing strategies with an innovative intervention (eSNS) to reduce social barriers to increasing SGM POC’s engagement in the full HIV prevention and care continuum.

This systematic literature review summarizes the evidence across 56 publications and pre-prints (January 2020-July 2023) with low-risk of bias based on JBI critical appraisal, that report adjusted estimates for the relationship between COVID-19 vaccination and Post-COVID-19 Condition (PCC) by timing of vaccination relative to infection or PCC-onset. Comparisons of adjusted vaccine effectiveness (aVE) against ≥1 PCC (vs. unvaccinated) across study characteristics known to impact PCC burden or VE against other COVID-19 endpoints were possible for 31 studies where vaccination preceded infection. Seventy-seven percent of pre-infection aVE estimates were statistically significant (range: 7%-95%). Statistically significant pre-infection aVE estimates were slightly higher for mRNA (range: 14%-84%) than non-mRNA vaccines (range: 16%-38%) and aVE ranges before and during Omicron overlapped. Our findings suggest that COVID-19 vaccination before SARS-CoV-2 infection reduces the risk of PCC regardless of vaccine type, number of doses received, PCC definition, predominant variant, and severity of acute infections included.

Abstract Background To assess the public health impact and economic value of an additional dose of BNT162b2 XBB.1.5-adapted COVID-19 vaccine 6 months after initial dose for those aged ≥65 years, compared to a single dose in the United States.Table 1.Clinical and Economic Outcomes of 2-dose vs 1-dose Strategy in the Population Aged ≥65 Years.LY = life year; QALY = quality adjusted life year; ICER = incremental cost effectiveness ratio Methods A combined Markov and decision tree model was used to estimate the public health impact of those aged ≥65 years receiving an additional BNT162b2 XBB.1.5-adapted dose over for a one-year time horizon (Oct 2023-Sept 2024). Age-stratified (65-74, 75+) annual attack, hospitalization, and vaccine coverage rates were informed by public health national surveillance data. Other age-stratified clinical, cost, and vaccine effectiveness parameters were informed by publications. Parameter uncertainty was examined through scenario and sensitivity analyses. Conservatively, indirect effects (e.g. reduced transmission) and broad societal benefits were not considered. Results For individuals aged 65 years and older, the model demonstrated that compared to a single dose, an additional dose of the BNT162b2 XBB.1.5-adapted COVID-19 Vaccine resulted in 338,148 fewer symptomatic cases, 19,947 fewer hospitalizations, and 591 fewer deaths. Cost of additional vaccinations were offset by costs averted (e.g., Long COVID (∼$1.3B), inpatient (∼$384M), indirect (∼$280M), and outpatient (∼$252M) costs), leading to a total cost savings of ∼$270.5M. The two-dose strategy for older adults improved health outcomes and lowered costs resulting in a dominant ICER (Table 1). The additional dose was predicted to be a budget-efficient solution for payers. Results were most sensitive to variation in the symptomatic rate of infection and the hospitalization rate. Conclusion An additional dose of BNT162b2 XBB.1.5-adapted COVID-19 vaccination for adults aged 65 years and older in the US may generate notable reductions in symptomatic cases, hospitalizations, and deaths and result in cost savings. The results demonstrate that administering an additional COVID-19 vaccine dose to older adults in the US should be an important public health goal, supporting current ACIP and CDC recommendations. Disclosures Alon Yehoshua, PharmD, MS, Pfizer Inc: Employer|Pfizer Inc: Stocks/Bonds (Public Company) Benjamin Yarnoff, PhD, Pfizer Inc: Grant/Research Support Manuela Di Fusco, PhD, Pfizer Inc.: Employee|Pfizer Inc.: Stocks/Bonds (Public Company) Santiago M.C. Lopez, MD, Pfizer Inc.: Employee|Pfizer Inc.: Stocks/Bonds (Public Company) Elizabeth A. Thoburn, MPH, Pfizer Inc: Employer|Pfizer Inc: Stocks/Bonds (Public Company) Abby Rudolph, PhD, Pfizer Inc: Employer|Pfizer Inc: Stocks/Bonds (Public Company) Kinga Marczell, PhD, Pfizer Inc: Grant/Research Support

The authors have withdrawn this manuscript because when updating the data analysis, the authors discovered that a data source with vaccination information was incorrectly linked to in the initial dataset used for this analysis. As a result, some individuals that were dropped from our initial analysis due to missing vaccine information should not have been dropped and could therefore impact vaccine effectiveness estimates. We are committed to ensuring the highest standards in our research, and correcting these issues will require substantial revisions and additional analyses. Therefore, the authors do not wish this work to be cited as reference for the project. If you have any questions, please contact the corresponding author. ### Competing Interest Statement Conflict of Interest Disclosures: Dr. Sun and Dr. Lupton reported being employees and stockholders in CVS Health during the conduct of this study. Dr. Rudolph, Mr. Khan, Dr. Puzniak, Dr. Jodar, and Dr. McLaughlin reported being employees and stockholders in Pfizer during the conduct of this study Funding/Support: This study was sponsored by Pfizer. Role of the Funder/Sponsor: The study design was developed by Pfizer and approved by CVS. CVS collected and analyzed the data. Pfizer did not participate in the collection or analysis of data. CVS and Pfizer participated in the interpretation of data, in the writing of the report, and in the decision to submit the paper for publication. Additional Contributions: The authors would like to acknowledge Dr. Jennifer Onwumeh-Okwundu, MD, who is an employee of Pfizer, Inc., and did not receive compensation beyond her salary, for her administrative support of this project. ### Clinical Protocols ### Funding Statement This study was funded by Pfizer. ### Author Declarations I confirm all relevant ethical guidelines have been followed, and any necessary IRB and/or ethics committee approvals have been obtained. Yes The details of the IRB/oversight body that provided approval or exemption for the research described are given below: Sterling IRB waived ethical approval for this work I confirm that all necessary patient/participant consent has been obtained and the appropriate institutional forms have been archived, and that any patient/participant/sample identifiers included were not known to anyone (e.g., hospital staff, patients or participants themselves) outside the research group so cannot be used to identify individuals. Yes I understand that all clinical trials and any other prospective interventional studies must be registered with an ICMJE-approved registry, such as ClinicalTrials.gov. I confirm that any such study reported in the manuscript has been registered and the trial registration ID is provided (note: if posting a prospective study registered retrospectively, please provide a statement in the trial ID field explaining why the study was not registered in advance). Yes I have followed all appropriate research reporting guidelines, such as any relevant EQUATOR Network research reporting checklist(s) and other pertinent material, if applicable. Yes

BackgroundImplementation science in public health has facilitated the translation of research findings into effective public health programming and evidence-based policy decision-making. One of the most prominent implementation science methodologies is intervention mapping, briefly defined as a rigorous protocol that guides the design of multi-level health promotion interventions and implementation strategies. In this manuscript, we describe our use and adaption of intervention mapping in Medical-Legal Partnerships, which are an integration of comprehensive legal services within primary health care and social service spaces working to mitigate the effects of negative social determinants of health for persons with HIV (PWH).MethodsIntervention mapping in this study was modified from a six-step to a five-step approach by integrating Step 4 and Step 5 of the original version of intervention mapping. The rationale for combining Step 4 and 5 into one step was that coherent, independent intervention packages existed for the provision of legal and HIV services, and it was determined through Step 1 of intervention mapping that these two existing intervention approaches can be integrated at the organizational level but should remain collocated at the patient level. Thus, our modified intervention mapping steps consisted of: (1) conducted needs assessments among medical legal partnerships (MLP) programs (providers and patients) serving PWH in order to identify the current landscape of MLP adoption and implementation in HIV care contexts and common components of those programs; (2) generated organizational and practice-level implementation outcomes and objectives, determinants and change objectives matrices to guide each strategy; (3) chose methods and mechanisms of change of the overarching implementation strategy; (4) produced implementation protocols and materials; and (5) developed a plan to evaluate implementation outcomes.ResultsFollowing intervention mapping author recommendations that not every step is needed in intervention mapping, using our modified intervention mapping approach resulted in a comprehensive organizational level intervention. Applying our adapted intervention mapping process resulted in the intervention package, OPAHL (Organizational Partnerships for Healthy Living), which currently is being tested for feasibility and preliminary effectiveness in a hybrid, randomized cluster trial in Philadelphia, Pennsylvania.ConclusionsThe work presented here provides a practical framework that can be replicated by other researchers and practitioners working on the social epidemiology of chronic illness, communicable disease, and access to and engagement with care.

Post-COVID-19 conditions (PCC) is an umbrella term that encompasses a range of signs, symptoms and conditions present weeks after the acute phase of a SARS-CoV-2 infection. This systematic literature review summarises the heterogeneous methodology used to measure PCC across real-world studies and highlights trends by region, age group, PCC follow-up period and data source. METHODS:Medline, EMBASE and the Cochrane Library were searched and supplemented with conference and grey literature searches. Eligible studies included individuals with (1) PCC or (2) a positive SARS-CoV-2 test or COVID-19 diagnosis who were followed over time. Included studies were published in English between 1 January 2020 and 14 November 2022. FINDINGS:Of 291 publications included, 175 (60%) followed individuals with confirmed COVID-19 over time for PCC and 116 (40%) used a prespecified PCC definition. There was substantial heterogeneity in study design, geography, age group, PCC conditions/symptoms assessed and their classification and duration of follow-up. Among studies using a prespecified PCC definition, author-defined criteria (51%) were more common than criteria recommended by major public health organisations (19%). Measurement periods for PCC outcomes from date of acute COVID-19 test were primarily 3 to <6 months (39.2%), followed by 6 to <12 months (27.5%) and <3 months (22.9%). When classified by organ/system, constitutional-related PCC were the most frequently assessed in adult (86%) and paediatric (87%) populations. Within constitutional symptoms, fatigue was most frequently assessed in adult (91.6%) and paediatric (95.0%) populations, followed by fever/chills (37.9% and 55%, respectively). CONCLUSIONS:PCC definitions are heterogenous across real-world studies, which limits reliable comparisons between studies. However, some similarities were observed in terms of the most frequently measured PCC-associated symptoms/conditions, which may aid clinical management of patients with PCC.CRD42022376111.

PURPOSE:HIV biomedical intervention uptake is suboptimal among Black sexually minoritized men (SMM) and transgender women (TW). Venues where people meet and interact shape HIV-related risk and prevention behaviors. We aimed to construct GPS-defined venue-based affiliation networks and identify the unique set of venues that could maximize reach of HIV biomedical interventions among Black SMM and TW. METHODS:We used baseline survey and GPS data from 272 Black SMM and TW in the Neighborhoods and Networks (N2) Cohort Study in Chicago, Illinois (2018-2019). We mapped participants' GPS data to the nearest pre-identified SMM- and TW-friendly venue (n = 222) to construct affiliation networks. Network analyses were performed to identify influential venues that can yield high reach to intervention candidates. RESULTS:Participants were affiliated with 75.5 % of all pre-identified venues based on GPS data. Two influential venues were identified in the non-PrEP use network, which when combined, could reach 52.5 % of participants not taking PrEP. Participants that could be reached through these two influential venues reported more non-main sex partners than participants not affiliated with either venue (p = 0.049). CONCLUSION:We demonstrate a potential for GPS-defined venue-based affiliation networks to identify unique combinations of venues that could maximize the impact of HIV prevention interventions.

BACKGROUND:Efforts to distribute naloxone have equipped more people with the ability to reverse opioid overdoses but people who use drugs are often reluctant to call 911 due to concerns for legal repercussions. Rural communities face unique challenges in reducing overdose deaths compared to urban communities, including limited access to harm reduction services as well as greater concerns about stigma and privacy. METHODS:The Rural Opioid Initiative was funded in 2017 to better understand the health-related harms associated with the opioid crisis in rural US communities and consists of eight studies spanning ten states and 65 counties. Each study conducted semi-structured qualitative interviews with people who use drugs to understand contextual factors influencing drug use and health behaviors. We analyzed qualitative data from seven studies with data available at the time of analysis to understand peer response to overdose. RESULTS:Of the 304 participants interviewed, 55% were men, 70% were white, 80% reported current injection drug use, and 60% reported methamphetamine use. Similar to what has been found in studies focused on urban settings, people who use drugs in rural communities use a range of strategies to reverse overdoses, including non-evidence-based approaches. Several reported that multiple doses of naloxone are needed to reverse overdose. Three themes emerged around the willingness to call 911, including (1) hesitancy to call 911 for fear of legal consequences, (2) negative perceptions or experiences with law enforcement officers, and (3) efforts to obtain medical intervention while avoiding identification/law enforcement involvement. CONCLUSION:People who use drugs employ multiple strategies to attempt overdose reversal, including non-evidence-based approaches. Greater education about the most effective and least harmful strategies is needed. Reluctance to call 911 is rooted in concerns about potential legal consequences as well as perceptions about law enforcement officers, which may be heightened in rural communities where people who use drugs are more easily identified by law enforcement. People who use drugs will go to great strides to connect their peers to needed medical services, suggesting that comprehensive interventions to reduce interactions with law enforcement officers and eliminate legal consequences for reporting overdoses are critical.

Background. Data on the effectiveness of BA.4/5 bivalent vaccine stratified by age and prior infection are lacking.Methods This test-negative study used data from individuals >= 5 years of age testing for SARS-CoV-2 with symptoms (15 September 2022 to 31 January 2023) at a large national retail pharmacy chain. The exposure was receipt of 2-4 wild-type doses and a BNT162b2 BA.4/5 bivalent vaccine (>2 months since last wild-type dose). The outcome was a positive SARS-CoV-2 test. Absolute (vs unvaccinated) and relative (vs 2-4 wild-type doses) vaccine effectiveness (VE) were calculated as (1 - adjusted odds ratio from logistic regression) x 100. VE was stratified by age and self-reported prior infection.Results. Overall, 307 885 SARS-CoV-2 tests were included (7916 aged 5-11, 16 329 aged 12-17, and 283 640 aged >= 18 years). SARS-CoV-2 positivity was 39%; 21% were unvaccinated, 70% received 2-4 wild-type doses with no bivalent vaccine, and 9% received a BNT162b2 BA.4/5 bivalent dose. At a median of 1-2 months after BNT162b2 BA.4/5 bivalent vaccination, depending on age group, absolute VE was 22%-60% and was significantly higher among those reporting prior infection (range, 55%-79%) than not (range, no protection to 50%). Relative VE was 31%-64%.Conclusions. BNT162b2 BA.4/5 bivalent showed early additional protection against Omicron-related symptomatic COVID-19, with hybrid immunity offering greater protection.

BACKGROUND:Prior studies have shown that individuals and their peers often have similar substance use behaviors, but the mechanisms driving these similarities - particularly in rural settings, are not well understood. The primary objectives of this analysis are to (1) identify factors that contribute to relationship turnover and maintenance within a rural network of persons who use drugs (PWUD), (2) determine whether assimilation and/or homophily shape participants use of injection drugs, heroin, and stimulants (methamphetamine and cocaine), and (3) assess the extent that these mechanisms influence networks ties and/or behaviors and whether these effects vary across time. METHODS:Sociometric network data were collected from a cohort of PWUD in rural Eastern Kentucky at baseline (2008-2010) and at four follow-up visits conducted approximately semiannually. Stochastic actor-oriented models (SAOMS) were used to model network structure and participant behaviors as jointly dependent variables and to identify characteristics associated with the maintenance, dissolution, and formation of network ties and changes in drug use behaviors. RESULTS:Findings suggest (1) greater network stability over time for reciprocal and transitive relationships, (2) both homophily and assimilation played a greater role in shaping injection drug use (IDU) initiation and cessation than they did in shaping heroin and stimulant use, and (3) the importance of these mechanisms appeared consistent over time. CONCLUSION:Given the stability of particular network structures and evidence of both homophily and assimilation with respect to drug-use behaviors, interventions that leverage social networks could be used to motivate health-promoting behaviors.

Background Injection-equipment-sharing networks play an important role in hepatitis C virus (HCV) transmission among people who inject drugs (PWID). Direct-acting antiviral (DAA) treatments for HCV infection and interventions to prevent HCV transmission are critical components of an overall hepatitis C elimination strategy, but how they contribute to the elimination outcomes in different PWID network settings are unclear. Methods We developed an agent-based network model of HCV transmission through the sharing of injection equipment among PWID and parameterized and calibrated the model with rural PWID data in the United States. We modeled curative and preventive interventions at annual coverage levels of 12.5 %, 25 %, or 37.5 % (cumulative percentage of eligible individuals engaged), and two allocation approaches: random vs targeting PWID with more injection partners (hereafter ‘degree-based’). We compared the impact of these intervention strategies on prevalence and incidence of HCV infections. We conducted sensitivity analysis on key parameters governing the effects of curative and preventive interventions and PWID network characteristics. Results Combining curative and preventive interventions at 37.5 % annual coverage with degree-based allocation decreased prevalence and incidence of HCV infection by 67 % and 70 % over two years, respectively. Curative interventions decreased prevalence by six to 12 times more than preventive interventions, while curative and preventive interventions had comparable effectiveness on reducing incidence. Intervention impact increased with coverage almost linearly across all intervention strategies, and degree-based allocation was always more effective than random allocation, especially for preventive interventions. Results were sensitive to parameter values defining intervention effects and network mean degree. Conclusion DAA treatments are effective in reducing both prevalence and incidence of HCV infection in PWID, but preventive interventions play a significant role in reducing incidence when intervention coverage is low. Increasing coverage, including efforts in reaching individuals with the most injection partners, preventing reinfection, and improving compliance and retention in preventive services can substantially improve the outcomes. PWID network characteristics should be considered when designing hepatitis C elimination programs.

Background: Recreating in waterbodies impacted by combined sewer overflows (CSOs) can present health risks due to exposure to microbial pathogens. This study compares population characteristics of those living within walking distance to CSO-impacted versus nonimpacted waters in Philadelphia to determine whether these populations differ by race, ethnicity, and sociodemographic characteristics.Methods: Adults recreating at or near natural water bodies in Philadelphia completed a questionnaire that assessed the average walking distance to each site. Walking distance boundaries informed by questionnaire responses were created around each waterbody in Philadelphia, and population-level census data corresponding with block groups included within each buffer were used to characterize those living near a CSO-impacted and nonimpacted waterbodies in Philadelphia.Results: Compared with populations residing in census block groups within walking distance to a nonimpacted waterway, populations living within the same distance to a CSO-impacted waterway were more likely to comprise Hispanic residents (standardized adjusted prevalence ratio [APR] = 1.13) and those living in poverty (APR = 1.21) and less likely to comprise White residents (APR = 0.76).Conclusion: These findings suggest that communities of color and those experiencing poverty are disproportionally impacted by environmental hazards.

AimIllicitly manufactured fentanyl and its analogs are the primary drivers of opioid overdose deaths in the United States (U.S.). People who use drugs may be exposed to fentanyl or its analogs intentionally or unintentionally. This study sought to identify strategies used by rural people who use drugs to reduce harms associated with unintentional fentanyl exposure.MethodsThis analysis focused on 349 semi-structured qualitative interviews across 10 states and 58 rural counties in the U.S conducted between 2018 and 2020. Interview guides were collaboratively standardized across sites and included questions about drug use history (including drugs currently used, frequency of use, mode of administration) and questions specific to fentanyl. Deductive coding was used to code all data, then inductive coding of overdose and fentanyl codes was conducted by an interdisciplinary writing team.ResultsParticipants described being concerned that fentanyl had saturated the drug market, in both stimulant and opioid supplies. Participants utilized strategies including: (1) avoiding drugs that were perceived to contain fentanyl, (2) buying drugs from trusted sources, (3) using fentanyl test strips, 4) using small doses and non-injection routes, (5) using with other people, (6) tasting, smelling, and looking at drugs before use, and (7) carrying and using naloxone. Most people who used drugs used a combination of these strategies as there was an overwhelming fear of fatal overdose.ConclusionPeople who use drugs living in rural areas of the U.S. are aware that fentanyl is in their drug supply and use several strategies to prevent associated harms, including fatal overdose. Increasing access to harm reduction tools (e.g., fentanyl test strips, naloxone) and services (e.g., community drug checking, syringe services programs, overdose prevention centers) should be prioritized to address the polysubstance-involved overdose crisis. These efforts should target persons who use opioids and other drugs that may contain fentanyl.

Background Accurate prevalence estimates of drug use and its harms are important to characterize burden and develop interventions to reduce negative health outcomes and disparities. Lack of a sampling frame for marginalized/stigmatized populations, including persons who use drugs (PWUD) in rural settings, makes this challenging. Respondent-driven sampling (RDS) is frequently used to recruit PWUD. However, the validity of RDS-generated population-level prevalence estimates relies on assumptions that should be evaluated.Methods RDS was used to recruit PWUD across seven Rural Opioid Initiative studies between 2018-2020. To evaluate RDS assumptions, we computed recruitment homophily and design effects, generated convergence and bottleneck plots, and tested for recruitment and degree differences. We compared sample proportions with three RDS-adjusted estimators (two variations of RDS-I and RDS-II) for five variables of interest (past 30-day use of heroin, fentanyl, and methamphetamine; past 6-month homelessness; and being positive for hepatitis C virus (HCV) antibody) using linear regression with robust confidence intervals. We compared regression estimates for the associations between HCV positive antibody status and (a) heroin use, (b) fentanyl use, and (c) age using RDS-1 and RDS-II probability weights and no weights using logistic and modified Poisson regression and random-effects meta-analyses.Results Among 2,842 PWUD, median age was 34 years and 43% were female. Most participants (54%) reported opioids as their drug of choice, however regional differences were present (e.g., methamphetamine range: 4-52%). Many recruitment chains were not long enough to achieve sample equilibrium. Recruitment homophily was present for some variables. Differences with respect to recruitment and degree varied across studies. Prevalence estimates varied only slightly with different RDS weighting approaches, most confidence intervals overlapped. Variations in measures of association varied little based on weighting approach.Conclusions RDS was a useful recruitment tool for PWUD in rural settings. However, several violations of key RDS assumptions were observed which slightly impacts estimation of proportion although not associations.

Although real-world studies demonstrate that those prescribed nirmatrelvir/ritonavir (and particularly within 5 days of symptom onset) are less likely to experience severe COVID-19 outcomes, prior studies show that only a small fraction of patients with COVID-19 who are eligible for nirmatrelvir/ritonavir receive a prescription. Studies calculating the proportion of nirmatrelvir/ritonavir prescriptions filled and identifying individual- and pharmacy-level correlates of filling nirmatrelvir/ritonavir are lacking. This retrospective cohort study included individuals aged ≥ 12 years with a nirmatrelvir/ritonavir prescription ordered at a large national retail pharmacy (December 22, 2021–August 12, 2023). Those taking contraindicated medications were excluded. For those with only one nirmatrelvir/ritonavir prescription ordered, the outcome was whether the prescription was filled (yes/no). In a subanalysis of these individuals, the outcome was whether the prescription was filled within 5 days of symptom onset (yes/no). For those with multiple prescriptions ordered, the outcome was whether > 1 (vs. 0 or 1) prescriptions were filled. A log-binomial regression with generalized estimating equations was used to identify individual (clinical and demographic) and pharmacy-level (percentage of trade area that is non-Hispanic white, urbanicity, US Census region, and tract-level area deprivation index) correlates. A total of 2,103,570 unique nirmatrelvir/ritonavir prescriptions were ordered for 1,985,990 individuals. Among the 95

BACKGROUND AND AIMS Analyzing long-term trajectories of alcohol use has the potential to strengthen policy and intervention priorities and timing. We identified and described trajectories of alcohol use and binge drinking frequency from mid-adolescence to early adulthood and measured the association of the role of early drinking initiation with trajectory membership. DESIGN Longitudinal cohort study SETTING: United States PARTICIPANTS: The National Longitudinal Survey of Youth 1997 is a nationally representative cohort of youth age 12-16 at baseline. The analytic sample included individuals who participated in >2 annual interviews between age 15 and 30 (n=8,809). MEASUREMENTS Participants self-reported the number of days in the past 30 days they: (1) drank alcohol and (2) binge drank [>5 drinks in one occasion]. We used group-based trajectory modeling to identify distinct trajectories from age 15-30 of past 30-day drinking and past 30-day binge drinking. Using multinomial logistic regression, we evaluated associations between early drinking initiation (≤14 years) and key demographics with trajectory membership. FINDINGS We identified 5 past 30-day drinking groups: late-escalating (16.0%), moderate-frequency (19.0%), high-frequency (11.1%), low-frequency (35.4%) and no/infrequent (18.4%). Early drinking initiation (versus later) was associated with higher odds of membership in the moderate (adjusted multinomial odds ratio [aMOR] = 4.32; 95% confidence interval [CI]: 3.65, 5.12) and high-frequency groups (aMOR = 4.17; 95%CI: 3.50, 4.97) than in the no/infrequent comparator trajectory. We identified 5 groups with distinct binge drinking frequency patterns: later escalating (9.9%), high-frequency (3.9%), low frequency (28.7%), earlier onset (9.5%), and no/infrequent (48.0%). Early initiation was associated with increased odds of membership in earlier onset and high-frequency groups compared with the no/infrequent group. For both outcomes additional differences in probability of group membership were identified by gender, racial identity, parental factors (religiosity, high school completion), and household characteristics (household size, income, and region of residence). CONCLUSIONS Youth in the United States appear to follow heterogeneous drinking and binge drinking trajectories from adolescence into adulthood. These may include higher-use trajectories as well as trajectories with different escalation timing (e.g., earlier vs. later). Early initiation of drinking may increase risk of membership in higher- and earlier-use trajectory groups.