Urban-Rural Variability in Infant Formula Availability and Product Variety in United States Counties from 2022 to 2024.

The United States experienced an acute shortage of infant formula products in 2022, which was preceded by general supply chain stress due to the COVID-19 global pandemic, a voluntary recall of certain powdered infant formula, and a temporary pause in production from a manufacturing facility. As infant formulas may serve as the primary or supplemental source of nutrition for many infants, the U.S. Food and Drug Administration (FDA), U.S. Department of Agriculture (USDA), and other governmental partners developed techniques to monitor the supply of infant formulas in the United States, including monitoring at subnational levels. Consumers in rural areas (nonmetro) of the U.S. can face unique challenges regarding food access compared to consumers in urban areas (metro). Therefore, we sought to investigate whether product variety of infant formulas available to consumers and infant formula product availability (estimated from in-stock rate) during the 2022 U.S. infant formula shortage and recovery differed. Using data on infant formula product listings and availability from retailers' online marketplaces, we observed that nonmetro counties had significantly lower infant formula product variety from 2022 to 2024 compared to metro counties. Estimated in-stock rates for nonmetro counties were higher than those for metro counties during the 2022 shortage and throughout much of the recovery period. Consistent with this finding, nonmetro consumers reported less difficulty purchasing infant formula in the fall of 2022 compared to their metro counterparts in the Household Pulse Survey. Despite lower product variety, these results suggest nonmetro consumers experienced comparable access to infant formula during the shortage. This study demonstrates that by combining retail-level in-stock rate data with household survey data, insights into potential geographic differences in food access during supply disruptions can be revealed.