Cronobacter sakazakii Infections in Two Infants Linked to Powdered Infant Formula and Breast Pump Equipment - United States, 2021 and 2022.

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.

Try Before You Buy: Are There Benefits to a Random Trial Period before Students Choose Their Collaborative Teams?

The cognitive and performance benefits of group work in undergraduate courses depend on understanding how to structure groups to promote communication and comfort while also promoting diversity and reducing conflict. The current study utilized social network analysis combined with self-reported survey data from 555 students in 155 groups to understand how students identified group members whom they wished to work with. Students' willingness to work with their peers was positively associated with behavioral traits pertaining to attention, participation, and preparedness in class. We tested whether preventing students from choosing their group members until completing a multiweek period of random assignment to different groups each week influenced group selection criteria, and we found little effect. Students continued to depend on demographic similarities such as gender and ethnicity when selecting groupmates and enforcing random interactions before the group formation did not influence group satisfaction and/or grades. Random interactions before group formation did influence the willingness of students to continue working with peers who were persistently poorly rated based on behavioral attributes and contribution to the group work. Thus, the effort of random assignment could be beneficial to identify struggling students and improve collaboration.