The Food and Drug Administration and the Centers for Disease Control and Prevention have issued warnings to hospitals on the use of powdered infant formula. The warnings come in the wake of an investigation into the death of a newborn from bacteria-laden formula.
"The result of this investigation indicates that the infection was associated with the presence of this bacteria in commercial powdered formula fed to the infant," said Dr. Matthew Kuehnert, a CDC infectious disease expert, in a press conference on April 12.
Last year, 10 infants were infected in a Tennessee intensive-care unit with the rare bacterium Enterobacter sakazakii. Investigators traced the infection to the commercial formula Portagen. The maker of Portagen, Mead Johnson Nutritionals, recalled the batch of formula in the Tennessee case last month.
The infant died from catching meningitis after being tube-fed the formula.
Kuehnert said infections from Enterobacter sakazakii are rare, but serious. He said it is unknown how many infections from E. sakazakii have occurred in the United States that can be traced to the use of contaminated powered infant formula in a neonatal health care setting.
Portagen has since written to health care providers about the risk, reminding them that powdered formula is not sterile.
In April, the FDA sent out letters to health professionals on the impending dangers.
"Clusters of E. sakazakii infections have been reported in a variety of locations over the past several years among infants fed milk-based powdered infant formula products from various manufacturers," the letter states. "One study tested milk-based powdered infant formula products obtained from a number of different countries and found that E. sakazakii could be recovered from 20 of 141 samples," or 20 percent.
In its recommendations to health care professionals, the FDA stated risks of infection can be reduced by:
- Reconstituting powdered formula using boiling water with subsequent refrigeration before feeding.
- Preparing only a small amount of reconstituted formula for each feeding to reduce the quantity and time that formula is held at room temperature for consumption.
- Minimizing the holding time before a reconstituted formula is fed.
- Minimizing the "hang-time" (amount of time a formula is at room temperature in the feeding bag and accompanying lines during enteral tube feeding) with no hang-time exceeding four hours.
The FDA also is urging health care providers to report any adverse events associated with the use of infant formulas as soon as possible.
Health officials are encouraging the use of alternatives to powdered formula.
"We realize that there are some situations where there is no alternative to powdered formula because there are special formulations that might be needed where the only formulation available is in powdered form," Kuehnert said. "But where there are other alternatives, we are encouraging providers to use those other alternatives."
Kuehnert also pointed out that the risk factors differ in a home setting.
"We believe that the risk is very low for healthy infants who consume powdered formulas," he said. "We believe that the highest risk is for newborn infants in hospital settings who consume powdered formulas," mainly for premature infants.
Kuehnert said liquid ready-to-feed formulas are marketed as commercially sterile, so there should be no bacteria in them.
According to the FDA, powdered infant formulas are not commercially sterile products. Powdered milk-based infant formulas are heat-treated during processing, but unlike liquid formula products, they are not subjected to high temperatures for sufficient time to make the final packaged product commercially sterile. Enterobacter sakazakii is described as a gram-negative, rod-shaped bacterium within the family Enterobacteriaceae. The organism was called "yellow-pigmented Enterobacter cloacae" until 1980, when it was renamed. The case-fatality rate among infected neonates has been reported to be as high as 33 percent.
What is alarming FDA officials is their awareness that a substantial percentage of premature babies in neonatal intensive care units are being fed non-commercially sterile dry infant formula.
According to FDA information, because powdered infant formulas are not commercially sterile products, the agency recommends these formulas not be used in neonatal intensive care settings unless there is no alternative.
"In general, powdered formula is not sterile, and this means that it commonly contains all types of bacteria, as many foods do," Kuehnert said. "Although food is not sterile, proper handling and preparation greatly reduces the risk of food-borne disease from harmful bacteria.
"But there are certain people, such as newborns or persons with impaired immune systems, that can become ill from certain food-borne bacteria."
The FDA currently is determining if additional specific measures may be needed to assure the safe use of dried infant formulas in neonatal intensive care settings or by other vulnerable infant populations.