Many parents in the United States are reeling from the effects of an outbreak of Cronobacter sakazakii in powdered infant formula. Between September 2021 and January 2022, four cases of Cronobacter infections in infants were reported to the FDA. In each case, the infants were fed powdered formula from Abbott Nutrition.(1)
Cronobacter sakazakii (formerly genus: Enterobacter) is an opportunistic Gram-negative, rod-shaped pathogen that can tolerate a wide range of temperatures and persist in dry environments, known as xerotolerance.(4) Symptoms of infection include irritability, poor feeding, temperature changes, abnormal body movements, grunting breaths, and jaundice. Severe infections can lead to sepsis and meningitis.(3) The chance of developing meningitis is highest in infants that are two months old or younger.(2) The bacterium is ubiquitous, being isolated from a range of environments and foods; the majority of Cronobacter cases occur in the adult population. However it is the association with intrinsically or extrinsically contaminated powdered formula which has attracted the main attention.
After two infant deaths, Abbott voluntarily recalled multiple lots of powered formula produced in their Sturgis, Michigan plant. Similac Sensitive, Similac Pro-total Comfort, Similac Advance, and Similac PM 60/40 were all implicated.(2) Using whole genome sequencing, an initial comparison of patient and environmental samples from the Michigan plant revealed that the identified strains of Cronobacter were not closely related. Additional sample analysis is still ongoing.(2)
Abbott is the largest manufacturer of infant formula in the United States. In addition to disruptions in the supply chain and limited formula suppliers, the temporary closure of Abbott’s Michigan plant, which is also their largest, has exacerbated the formula shortage. Many parents have been met with empty shelves or tight limits on purchases.(5) On May 18th, President Biden invoked the Defense Production Act to increase the domestic production of infant formula. Biden also authorized the Defense Department to import thousands of pounds of formula from overseas.(6)
The FDA recently reached an agreement with Abbott to reopen the Michigan plant in the first week of June. Abbott estimates an eight to ten week lead time for new formula to be produced.(6) Infant formula should not be diluted and caretakers should never attempt to make their own formula. Do not purchase imported formula online due to the risk of counterfeit products.(3) ) If your regular formula is unavailable, contact your baby’s healthcare provider for assistance or visit healthychildren.org for more information.(7) The CDC encourages individuals to report any diagnosed Cronobacter infections to local or state health departments.(2)
Early identification of Cronobacter sakazakii is important to avoid additional infant infections from powdered formula. Hardy Diagnostic offers HardyCHROM™ sakazakii for the selective isolation and differentiation of Cronobacter sakazakii. This chromogenic medium provides easy identification of colonies of Cronobacter sakazakii, which appear smooth and blue-green as seen in the photo below.