evidence: Measles Outbreak Associated with a Migrant Shelter — Chicago, Illinois, February–May 2024 [...] After identification of a large measles outbreak among migrants, primarily from Venezuela, who resided in a shelter, active case-finding and rapid mass vaccination of residents likely reduced transmission and outbreak size and duration (5). Engagement of community partners contributed to the success of these public health interventions. [...] Suggested citation for this article: Gressick K, Nham A, Filardo TD, et al. Measles Outbreak Associated with a Migrant Shelter — Chicago, Illinois, February–May 2024. MMWR Morb Mortal Wkly Rep 2024;73:424–429. DOI: http://dx.doi.org/10.15585/mmwr.mm7319a1.