Millions of infants worldwide are fed powdered infant formula (PIF) every day with good health outcomes (1,2). However, unlike liquid concentrate and ready-to-feed infant formulas, PIF (starter and follow up) is not a commercially sterile product, even when manufactured to meet current microbiological standards. It has been implicated in rare but very serious infant illness when contaminated. While a wide variety of different bacteria have been found in PIF,