Clostridium botulinum. The usual cause of bulging canned foods. Don’t ever try to taste it. Even a very small amount is dangerous.

Onset of  foodborne botulism is usually 18 to 36 hours after ingestion of the food containing the toxin, although cases have varied from 4 hours to 8 days. Early signs of intoxication consist of marked lassitude, weakness and vertigo, usually followed by double vision and progressive difficulty in speaking and swallowing. Difficulty in breathing, weakness of other muscles, abdominal distention, and constipation may also be common symptoms.

Aflatoxins are toxic, a mycotoxin produced by Aspergillus flavus. This fungi is in soil, decaying vegetation, hay, and grains. It grows whenever conditions are favorable. Aflatoxin occurs in cereals and may transfer to meat products through cross-contamination.

Norovirus. As its name implies, as virus. A group that cause gastroenteritis. The illness is characterized by infammation of stomach and intestine lining.

information under black quotes was  sourced from USFDA website.