Eating a bad stomach is usually considered as a possible bacterial infection such as E. coli, Salmonella, and Orthobacterium parahaemolyticum. 1. Escherichia coli: it is a conditionally pathogenic bacteria that usually resides in the intestinal tract of animals and causes gastrointestinal infections when the diet is unclean, leading to the occurrence of abdominal pain and diarrhea. 2. Salmonella: it is an enteropathogenic gram-negative bacillus, which mainly resides in the intestinal tract of humans and animals, and usually causes gastrointestinal infections when unclean food is eaten by mistake, resulting in severe diarrhea in infected people. 3. Vibrio parahaemolyticus: It is a common gram-negative pathogen, mainly residing in seawater. If you eat seafood contaminated with this bacteria, it can cause food poisoning, leading to vomiting, diarrhea and other symptoms. If you suffer from the above symptoms, it is recommended that you go to the hospital as soon as possible for examination and take appropriate measures.