Cereulide is a toxin produced by some strains of Bacillus cereus, a common environmental bacterium found in soil, dust, and raw agricultural materials.
Cereulide acts on cells’ mitochondria and can cause rapid-onset symptoms like vomiting, stomach cramps, and diarrhea.
During manufacturing, raw ingredients used in baby formula such as oils (e.g., arachidonic acid, or ARA oil) or dry powders can be contaminated with spores of B. cereus or pre-formed cereulide.
Because spores and the toxin survive processing, they must be prevented by testing ingredients before inclusion.
e.g. here is the recall in Flanders,Belgium,for 2026-01-05, so more than a month ago:
https://www.vrt.be/vrtnws/nl/2026/01/05/nestle-nan-babyvoedi...
Here is one English source about the deaths in France:
https://www.independent.co.uk/news/world/europe/france-nestl...
It is a shame for Nestle to have to import ingredients from China for such simple products anyway. It's the greed at topest level.
Problems with babies diets are hard to identify generally. Frankly I'm amazed this was identified with only 36 sick infants.
Consumers of baby formula are known for having a high baseline rate of spewing things out their holes and having a pretty high standard deviation on top of that rate. And of course the babies are getting older all this time and changing their diets and responses to things. So a large subset of parents are just gonna write it off as "I guess now that my baby is X months old this brand of formula gives him the shits/upsets their stomach." There's also likely confounding changes. And it's not like they can tell you "hey this tastes different than last week's". It's gonna take a while to ID that there's a problem and then actually correlate it to anything (consumption of a specific problem product in this case).
It's not like the kids are turning blue or some other "obviously not right" symptom. That'd be identified and root caused within the week of the first case.