Navigating public health priorities: Substance use research in a constrained funding environment

South Africa's substance use, which affects 13% of the population, fuels injuries, disease and mental health issues, and disproportionately impacts at-risk groups.Reduced international funding jeopardises vital research, harm reduction interventions and healthcare access.Increased domestic investment, braided funding and diverse partnerships are critical to maintain services and reduce reliance on external donors.These endeavours ensure long-term public health interventions to comprehensively combat substance use disorders.Substance use is a critical public health issue in South Africa, which directly fuels intentional and unintentional injuries as well as communicable and non-communicable diseases, and has a multidirectional association with mental health problems.Over the last decade and a half, US federal agencies like the Centers for Disease Control (CDC), the National Institutes of Health, and the National Institute of Mental Health have supported much of the research and implementation in this area.The current funding crisis will severely undermine South Africa's ability to gather essential epidemiological data, combat the substance use epidemic, and deliver evidence-based and harm reduction interventions. Substance use crises, harm reduction initiatives, and impactsSouth Africa faces a deepening substance use epidemic, with illicit drug consumption increasing tenfold between 2002 and 2017. 1 Approximately 13% of the population meets DSM-5 and ICD-11 criteria for substance use disorders during their lifetime, driven by alcohol, tobacco, cannabis, heroin, cocaine and methamphetamines. 2 Among illicit drugs, opioids are the largest contributor to the global burden of disease, accounting for almost 12 million disability adjusted life years lost. 3South Africa has seen an increase in the proportion of treatment admissions for opioid-related disorders over the last 6 years. 4At-risk populations, young people, and key populations are disproportionately affected, with socio-economic factors such as unemployment (38.8% nationally) and poverty amplifying vulnerability.