By: Robert M. Califf, M.D., Commissioner of Food and Drugs
Last year, following the February Abbott recall and subsequent shortage of infant formula, many households across the U.S. heard about a pathogen (bacterium) for the first time called Cronobacter sakazakii. This pathogen isn’t new to the food industry but is not well-known among the general public, so I thought I would catch up with you on some basics about Cronobacter.
What We Know about Cronobacter
Cronobacter is found naturally in the environment – for example, in our yards, kitchens, and living rooms. It can live on surfaces like kitchen counters, sinks, or also on food facility manufacturing equipment. While Cronobacter is harmless for most people, it can cause life threatening infections in infants, particularly those who are younger than two months old, premature, immunocompromised, or of low birth weight.
Evidence has pointed to Cronobacter contamination occurring both in the food facility manufacturing environment and in the home, as demonstrated in the CDC’s recent Morbidity and Mortality Weekly Report (MMWR). Because this pathogen is so ubiquitous in the environment, public health officials stress the importance of safe preparation and storage of powdered infant formula to avoid contamination at home, and the FDA sets certain requirements to help control for it in the manufacturing environment. As part of our work here at the agency to continue to enhance safety in the infant formula manufacturing environment, the FDA recently sent a letter to industry with recommendations for improvements that can be made industry wide.
Addressing Cronobacter Knowledge Gaps
Fundamentally, we need more information about Cronobacter infections. For example, when an infection occurs, it is difficult to determine whether the source of the infection is due to an infant formula product or contamination by some other means in the home. While Cronobacter infections seem very rare, that may be because only two states – Minnesota and Michigan – require reporting Cronobacter infections to public health departments.
Other cases may go unreported or reported as other illnesses such as meningitis, which can be caused by Cronobacter. Unless detailed studies are done, the diagnosis as a Cronobacter illness may be missed. The lack of mandatory reporting significantly hampers the ability to fully understand Cronobacter’s public health impact.
Additionally, there is no robust library of genetic data for Cronobacter that would be helpful to definitively link clinical samples to their source – i.e., certain foods or environments – and to identify repeat sources of clinical illnesses. The ability to match the exact genetic sequence of pathogens causing infection in a patient to those isolated from the source has revolutionized our ability to detect and control small and large outbreaks quickly. Unfortunately, right now, the isolate library housed by National Center for Biotechnology Informatics (NCBI) only has roughly 1,300 Cronobacter isolates compared with over 525,000 for Salmonella.
Without this genomic data, it will remain difficult to determine the source of Cronobacter infections – and equally as challenging to prevent future ones. We’re encouraging industry and public health partners to help us build this library by conducting more frequent whole genome sequencing (WGS) and sharing the findings so that we can all benefit from the data.
Catch up with you next time.