This paper studies how better access to public health insurance affects infant mortality during pandemics. The analysis combines cross-state variation in mandated eligibility for Medicaid with two influenza pandemics that arrived shortly before and after the program's introduction in 1965. We find that better access to public health insurance in high-eligibility states substantially reduced pandemic infant mortality. The reductions in pandemic infant mortality are too large to be attributable solely to new Medicaid recipients, suggesting that expanded access to public health insurance helped mitigate disease transmission among the broader population.