The impacts of infectious disease outbreaks, epidemics, and pandemics are not gender neutral. Instead, infectious diseases and gender-based violence (GBV) mutually reinforce each other. Women and girls in humanitarian settings are disproportionately impacted as crises exacerbate gender inequality, violence, and community transmission. A syndemic model of infectious disease and GBV draws attention to their critical linkage, enabling more effective approaches to address both infectious disease transmission and GBV prevalence.