A group of bacteria, Cronobacter (formerly called Enterobacter sakazakii) are found naturally in the environment surviving even in very dry conditions. Sometimes, the bacteria have been seen in dry foods including powdered infant formula, powdered milk, herbal teas, and starches. Even though illness associated with the Cronobacter bacteria is very rare, it often is deadly in infants, usually occurring in the first days or weeks of life. Previously, four to six cases of Cronobacter illness in infants were reported each year to the CDC. However, there is no reporting requirement and, with recent increased awareness of Cronobacter illness in infants, in 2011 the number of reports increased. The CDC received reports on 13 cases in 2011.
Cronobacter bacteria can cause severe blood infections (sepsis) or meningitis (an inflammation of the membranes that protect the brain and spine). Infants, two months of age and younger, are may develop meningitis if they are infected with Cronobacter bacteria. Infants born prematurely and those with weakened immune systems are also at increased risk for serious Cronobacter infections. In infants, the illness generally starts with fever. It usually includes poor feeding, crying, or listlessness. The CDC recommends that young infants with these symptoms should be taken to a doctor.
In some CDC outbreak investigations, Cronobacter bacteria were found in powdered infant formula that had been contaminated in the factory. In other cases, Cronobacter bacteria might have contaminated the powdered infant formula after it was opened at home or elsewhere during preparation.
Using current manufacturing methods, it is not possible to eliminate all germs from powdered infant formula in the factory. Powdered infant formula can also be contaminated after the containers are opened. Very young infants, infants born prematurely, and infants with weakened immune systems are at the highest risk.
The CDC recommends safe preparation of dry infant formula; considering, as an alternative, the use of liquid infant formula; and other steps to prevent Cronobacter bacteria illness. See the announcement.