What is Cronobacter sakazakii? And why is it a danger in powdered infant formula? This pathogen is not well known but can cause serious illness and death in infants, especially babies who were premature, low birth weight, or have other health conditions or compromised immune systems. It is one of the costliest foodborne pathogens because of loss of life and serious health problems that can persist even when a patient recovers. The fatality rate in infants, even older infants, ranges from 40 to 80%. The cost of each case is estimated at $1,000,000, according to a study published in Front Microbiol.