Foodborne Infections and Mortality Associated With Expressed Breastmilk, Donated Breastmilk, and Infant Formula in High-Income Countries: A Scoping Review of Peer-Reviewed Evidence Cases

Infant feeding influences infant growth, development, survival, and long-term health. Maternal expressed breast milk (MEBM), donor human milk (DHM), and powdered infant formula (PIF) serve as alternatives when direct breastfeeding is not feasible. However, these alternatives are susceptible to microbial contamination, posing risks of infection and mortality. Despite concerns about foodborne infections in neonates, no comprehensive synthesis has examined infections and deaths directly linked to contaminated infant milk across different feeding methods. This scoping review examines infections and deaths associated with contaminated MEBM, DHM, and PIF in high-income countries over the past 25 years, identifying key pathogens and sources of contamination. A systematic search on Medline, Scopus, and Embase identified a total of 6867 studies, of which 19 were selected, with an additional study from references. Data extracted for feeding type, pathogen, contamination source, and clinical outcomes. Among 175 cases, 55 led to systemic infections, including 13 deaths. Cronobacter sakazakii and Pseudomonas aeruginosa were the most frequently implicated pathogens in the published papers. PIF and DHM were more often linked to infections than MEBM. Besides intrinsic PIF contamination, hospital milk blenders and dishwashers were found to be positive for pathogens. DHM cases reported positive cultures of the nasogastric tubes, milk bank pasteurizers, and hospital bottle warmers. MEBM contamination was reported through breast pumps and hospital sinks and drains. This review highlights the need for enhanced hygiene protocols in handling infant milk. These findings inform clinical and public health policies aimed at minimizing infection risks associated with alternative infant feeding methods.