Which bacteria is commonly responsible for noninvasive infectious diarrhea resulting from contaminated dairy products?

Staphylococcus aureus is commonly responsible for noninvasive infectious diarrhea associated with contaminated dairy products. This bacterium can produce enterotoxins that are preformed in foods, particularly in dairy products like milk, as well as in cream-based items and mayonnaises. When these foods are ingested, the enterotoxins can lead to rapid-onset gastrointestinal symptoms, including diarrhea and vomiting, typically occurring within a few hours after consumption.

The hallmark of Staphylococcus aureus food poisoning is that it is caused by the ingestion of preformed toxins rather than the bacteria itself multiplying within the gastrointestinal tract. This distinguishes it from other bacterial causes of diarrhea that often require the organism to proliferate within the gut to cause illness.