Recently, certain infant formula products were found to contain the pathogenic bacterium "Enterobacter sakazakii." Neonatology experts warn that if newborns (especially premature or low-birth-weight infants) contract this bacteria, they face a high risk of severe enterocolitis and sepsis, which can be life-threatening.
Enterobacter sakazakii
Also known as Sakazaki's Enterobacter, this bacterium belongs to the Enterobacteriaceae family. Renamed from Enterobacter sakazakii in 1980, it causes severe neonatal meningitis, enterocolitis, and bacteremia with mortality rates exceeding 50%.Microbiologists currently do not know the source of Cronobacter sakazakii contamination, but numerous case reports indicate infant formula is the primary identified route of infection.
Cronobacter sakazakii poses the greatest risk to newborns (28 days old or younger), infants under 2 months old, and especially premature infants, those weighing less than 2.5 kilograms at birth, and infants with weakened immune systems.Due to their underdeveloped immune defenses, once infected, these bacteria often proliferate extensively in the colon before migrating to the small intestine. They can then penetrate the intestinal wall (which is thin and highly permeable in newborns) and directly enter the bloodstream, triggering neonatal sepsis.
Generally, if a child exhibits bloody, mucus-containing stools, doctors will recommend a PCR (polymerase chain reaction) test to determine whether the child has indigestion, a viral infection, or an infection with Cronobacter sakazakii.
Beware of the "well-behaved baby" who neither eats nor cries
Infants infected with Cronobacter sakazakii often refuse to feed and show no signs of distress, appearing to parents as "well-behaved babies." In reality, the infection triggers sepsis, which suppresses the central nervous system and causes lethargy, leaving the infant too weak to cry. Additionally, the proliferation of bacteria in the intestines causes discomfort, further reducing the infant's desire to feed.
Experts therefore caution that when a newborn shows "no feeding and no crying," it may indicate sepsis. Early medical intervention at this stage yields excellent outcomes. Infants mistakenly labeled "good babies" by parents may experience delayed treatment, leading to more severe illness and a higher mortality rate for sepsis.
Finish formula within one week after opening the can.
All infant formula undergoes testing for Enterobacter sakazakii before leaving the factory. Liu Haiyan explains that while bacterial counts may be within limits at production, prolonged storage or transportation—especially near the expiration date—can allow bacteria to multiply significantly.
Therefore, formula stored longer poses greater risks to infants. Experts recommend selecting relatively "fresh" formula for newborns—such as batches recently manufactured. Liu Haiyan emphasized that hospitals strictly avoid using near-expiration formula for premature infants due to their vulnerable immune systems.