What is already known about this topic?
Infections caused by Cronobacter sakazakii are rare but can cause severe illness and death in infants.
What is added by this report?
Whole genome sequencing analysis was used to link one case of Cronobacter sakazakii infection in a full-term infant to an opened can of powdered infant formula, and another unrelated fatal case in a premature infant to contaminated breast pump equipment.
What are the implications for public health practice?
Increased awareness of the widespread presence of Cronobacter in the environment, along with promotion of safe preparation and storage of powdered infant formula, and careful cleaning and sanitization of breast pump equipment, could prevent potentially devastating infections.
Cronobacter sakazakii, a species of gram-negative bacteria belonging to the Enterobacteriaceae family, is known to cause severe and often fatal meningitis and sepsis in young infants. C. sakazakii is ubiquitous in the environment, and most reported infant cases have been attributed to contaminated powdered infant formula (powdered formula) or breast milk that was expressed using contaminated breast pump equipment (1–3). Previous investigations of cases and outbreaks have identified C. sakazakii in opened powdered formula, breast pump parts, environmental surfaces in the home, and, rarely, in unopened powdered formula and formula manufacturing facilities (2,4–6). This report describes two infants with C. sakazakii meningitis reported to CDC in September 2021 and February 2022. CDC used whole genome sequencing (WGS) analysis to link one case to contaminated opened powdered formula from the patient’s home and the other to contaminated breast pump equipment. These cases highlight the importance of expanding awareness about C. sakazakii infections in infants, safe preparation and storage of powdered formula, proper cleaning and sanitizing of breast pump equipment, and using WGS as a tool for C. sakazakii investigations.