WHiSE 2.0 (Walking for Harm Reduction through Street Engagement) is a prospective cohort study that examines the harm reduction needs, service use patterns, and priorities of Indigenous people who use drugs in three cities in northern Ontario: Thunder Bay, Sault Ste. Marie, and Sudbury. The study expands on the 2020 WHiSE work in Thunder Bay to achieve broader geographic coverage and deeper community engagement. The primary objective is to inform and strengthen access to culturally safe, locally tailored harm reduction services for Indigenous people who use substances.
The study was conducted using a community-based research approach guided by Indigenous leadership. Research partnerships included the Ontario Aboriginal HIV/AIDS Strategy (Oahas) and Elevate Northwestern Ontario (ENWO), together with academic investigators. The protocol was grounded in Indigenous research methodologies that prioritize relationality and trust-based relationships with community organizations.
Eligible participants self-identified as Indigenous, lived in one of the study regions, and had used substances within the previous three months. Participants completed an interviewer-administered questionnaire lasting approximately one hour. The coordinating site built on prior engagement through ENWO in Thunder Bay.
Data collection used structured interviewer-administered questionnaires. Descriptive statistics summarized demographic and cultural characteristics, impacts of colonization, substance use and health behaviours, and harm reduction knowledge. Results were stratified by city to highlight local differences in needs and service use.
The cohort consists of 356 participants enrolled across three sites: 173 in Thunder Bay, 101 in Sault Ste. Marie, and 82 in Sudbury. The majority of participants identified as First Nations, with proportions of 93.1% in Thunder Bay, 76.8% in Sudbury, and 75.2% in Sault Ste. Marie. Further demographic details are reported within the manuscript.
Participants experienced high levels of housing instability. Across the cohort, 39.0% reported sleeping on the street, 28.3% stayed in a shelter, and 23.3% reported couch surfing. Additionally, 41.9% were staying at a family or friend’s home. These measures underscore the intersecting social determinants that shape risk and access to services among Indigenous people who use drugs.
Substance use modalities reported across all sites included injection, ingestion, smoking, and snorting or inhalation. Specifically, 43.3% of participants reported injecting drugs, 31.5% reported ingesting drugs, 92.1% reported smoking drugs, and 38.5% reported snorting or inhaling drugs. These prevalence figures reflect diverse consumption methods within the cohort and inform the types of harm reduction interventions that may be most relevant locally.
Across all sites, 84.0% of participants reported knowing what harm reduction was. Testing for blood-borne infections was common: 82.3% of respondents had ever had an HIV screening test and 84.3% had ever had HCV testing. The study situates these findings amid service availability changes in the region, including reported closures of supervised consumption sites in Ontario on March 31, 2025, which have implications for access to safer spaces and related services.
Cultural practices were an important component of participants’ lives. Overall, 71.3% of participants engaged in ceremonies, and 22.2% reported that cultural teachings affected their harm reduction practices. These results highlight the potential role of Indigenous knowledge and cultural supports in shaping harm reduction approaches.
WHiSE 2.0 was developed in a context of elevated opioid-related harms and infectious disease concerns in the Thunder Bay area. Between 2005 and 2016, the crude rate of emergency department visits for opioid overdose in the Thunder Bay District increased from 32.9 to 53.4 per 100,000 people. From 2016 to 2020, 78.9% of newly diagnosed HIV cases in the Thunder Bay District Health Unit occurred among Indigenous people and populations experiencing homelessness or under-housing. The TBDHU declared a community HIV outbreak on June 25, 2019, with transmission linked to sexual activity and sharing injection supplies. The literature notes that injection drug use was a primary exposure category for both HIV and HCV among Indigenous populations; however, comparable epidemiologic data for Sudbury and Sault Ste. Marie were limited prior to this study.
The manuscript also cites broader Ontario data highlighting HCV burden among status First Nations people and elevated HCV incidence in some rural and remote First Nations communities, emphasizing the need for prevention and tailored care that accounts for demographic differences, including sex and age distributions.
All relevant cohort data are described within the manuscript. The dataset forms part of a larger prospective cohort that remains in active data collection. There are ethical restrictions on data sharing to uphold Indigenous data governance principles. Small cell sizes and risks of participant disclosure (including those living with HIV) mean a minimal public dataset is not possible. Access to de-identified data requires completion of a data request form available from the study contact (benoitresearch.utsc@utoronto.ca) and review by an Indigenous Advisory Committee and community investigator partners (Oahas and ENWO). Future analyses using the data must be important to and benefit the community investigators and the study communities.
The study was funded by the Canadian Institutes of Health Research (grant PJT 180395). The funder did not influence study design, data collection and analysis, manuscript preparation, or the decision to publish. The authors declared no competing interests. WHiSE 2.0 is reported as the first prospective cohort study specifically examining harm reduction needs among Indigenous people who use substances in northern Ontario and highlights urgent service gaps and the importance of culturally rooted, locally tailored harm reduction strategies led by Indigenous knowledge and leadership.