Modeling the 2026 Bangladesh Measles Outbreak: A Two-Age-Class SEIRV Approach with Stability and Sensitivity Analysis

Bangladesh experienced its worst measles outbreak since 2005 in March–April 2026, with 79%of cases in children under five, driven by falling measles-rubella coverage from 88.6%/89%(2019) to 86%/80.7% (2023). We formulate a two-age-class SEIRV model for a closed 0–24month cohort approximating Bangladesh’s EPI schedule and derive a cohort-restricted controlreproduction number Rc ≈1.93 via the exact spectral radius of the next-generation matrix. Weestablish demographic well-posedness, local and global stability of the disease-free equilibrium, and existence of a positive endemic equilibrium with numerically supported uniqueness.A Latin Hypercube Sampling/PRCC analysis of eight parameters identifies MCV1 coverageand the recovery rate as dominant drivers of Rc, peak burden, and cumulative onset of infectiousness. A 48.2% reduction in effective susceptibility would bring Rc to 1; Rc stays above 1(about 1.07) even under the WHO 2030target. Age-disaggregated simulation and a growth-ratecheck against outbreak data support these conclusions. [submitted]