Big Events and Risks to Global Substance Using Populations: Unique Threats and Common Challenges.

In this commentary, we review a set of "Big Events" from around the world that have adversely impacted substance using populations by first identifying common thematic areas between them, and then describing the unique challenges faced by the diverse and vulnerable populations impacted. The Big Events reviewed are multifaceted and complex in nature, and include the recent global financial crisis, economic and trade sanctions, political transition and its impact on ethnic minorities, colonialism and indigenous communities, and ecological disasters. All have led to immense trauma, displacement, and disruption to critical healthcare services/treatment for people who use drugs, populations who are left underserved in the midst of these crises. It is our hope that through this comparative assessment, global policymakers will proactively identify Big Events and prioritize the development of interventions and policy that meet the unique and immediate needs of substance using population in order to mitigate the significant negative short- and long-term impacts on global public health.