A stomach infection is any infection that affects the stomach. It can be caused by an accumulation of bacteria in your stomach or by a virus.
Stomach viruses usually infect the intestines and do not result in symptoms specific to the stomach. Gastroenteritis and food poisoning are both types of digestive system infections that can affect the stomach.
A person with a stomach infection may present with symptoms such as nausea, vomiting, fever, chills, diarrhea, abdominal cramping and pain.
This particular bacteria lives on the lining of the stomach hence focusing on the digestive tract, which leads to acid secretion in the stomach itself.