The global population of refugees, asylum seekers, and internally displaced persons dramatically rose between 2010 and 2025. Climate change is becoming an emerging driver of migration and displacement. Climate-related effects can impact population stability through long-term effects (e.g., droughts and food insecurity), short-term effects (e.g., extreme weather events), or by compounding other threats, such as war, poverty, and political instability. Emerging infections and infections of public health importance can complicate both natural and human-made humanitarian crises. Irregular migration through novel pathways introduces new interactions between migrating people and the environment potentially resulting in “spillover” of zoonotic pathogens to humans. Clinical and public health authorities should consider unique considerations of special populations who may be disproportionately vulnerable during migration and displacement.