Infectious Disease in Illinois

Questions and Answers about Cronobacter sakazakii (formerly Enterobacter sakazakki) and the Use of Powdered Infant Formula (PIF)

If you are concerned about your infant’s health or the infant is experiencing symptoms of meningitis or septicemia, which include fever, fussiness, vomiting, lethargy, not eating, listlessness or spine arching, immediately contact your pediatrician or local health care provider.

  • What is Cronobacter sakazakii? What diseases can the bacteria cause?

Cronobacter sakazakii, formerly known as Enterobacter sakazakii, is a bacterium. Illness from this organism is rare, but infection can cause meningitis and septicemia in infants. The infection can be fatal or result in long-term complications.

  • Where does the bacterium come from? Where can it be found?

The bacteria are everywhere in the environment and have been found in the intestinal tract of healthy humans and animals. Ingestion of food contaminated with the bacteria or the presence of the bacterium on surfaces, such as kitchen countertops, does not always result in illness.

  • How does powdered infant formula get contaminated with Cronobacter sakazakii? Can it be found in other foods?

The way powdered infant formula becomes contaminated with these bacteria is not well understood. Contamination can occur from the raw ingredients used in the formula, during the manufacturing process or during the preparation/reconstitution process. Contamination also may occur through blenders, feeding bottles and utensils used to cleanse feeding bottles. Contamination may be more likely when reconstituted formula is kept at improper temperatures prior to use or for a longer duration than suggested by manufacturers. The organism has been found in other foods, but only powdered infant formula has been linked to disease outbreaks.

  • Who is at risk for getting this infection?

Those at elevated risk for infection are premature and low birth-weight infants, infants with immune system problems or babies born to mothers with immune system problems.

  • How can this risk be minimized or reduced?

Commercially sterile liquid formula is less frequently associated with illness and can be used in instead of powdered infant formula, where possible. If powdered infant formula is chosen, remember it is not a sterile product and the use of boiled water can reduce the risk of infection. This includes tap water, bottled water or water specifically indicated for use in infant care.

Powdered infant formula should be prepared/reconstituted immediately before feeding time, according to package instructions and cooled appropriately before giving to the infant.

Additional tips to reduce infection risk

Clean utensils

  • Wash hands, forearms and fingernails thoroughly before handling any feeding materials or preparing formula.
  • All bottles, nipples, caps and rings should be washed in hot, soapy water with thorough rinsing.

Preparing formula

  • Before use, powdered formula should be kept dry in an airtight container with a firm cap or lid and stored in a cool, dark area. Make sure the expiration date has not passed.
  • During formula preparation, bring water to a bubbling boil for two minutes and allow the water to cool before mixing.
  • Avoid reheating formula and do not use a microwave oven to warm the formula.

Storing formula

  • Formula should be prepared in small amounts immediately before feeding time to minimize the need for storing prepared/reconstituted formula.
  • Prepared/reconstituted formula should not be stored at room temperature for more than one hour or more than four hours in the refrigerator.
  • Throw out any formula left in a bottle after feeding.

Additional information for the best practices in infant formula preparation can be found at:

Illinois Department of Human Services:
World Health Organization (WHO):

idph online home
Illinois Department of Public Health
535 West Jefferson Street
Springfield, Illinois 62761
Phone 217-782-4977
Fax 217-782-3987
TTY 800-547-0466
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