Foodborne diseases

A great many patients seen in emergency rooms suffer from foodborne diseases, often informally called food poisoning, which affect the gastrointestinal tract. The most common foodborne infections in developed countries cause vomiting and diarrhea, frequently self-limiting but potentially causing dangerous dehydration -- and a great deal of discomfort that can be alleviated. Some foodborne diseases, either infections such as botulism or from poisonous mushrooms or other naturally occurring toxins, can be fatal.

The amount of time between food ingestion and the onset of symptoms often helps the diagnosis.

Time to onset	Likeliest causes
< 1 hour	Chemical contamination, ciguatera, scombroid poisoning
3-6 hours	Staphylococci

Staphylococcal and streptococcal infection

The effects of both are caused by bacterial toxins rather than classic bacterial invasion, an exotoxin in the case of staphylococci and endotoxin with salmonella.