Is the presence or absence of Helicobacter pylori in gastric mucosa a greater risk?

Helicobacter pylori is a unique organism which is pathogenic for stomach-duodenum (chronic gastritis, duodenal ulcer, gastric ulcer, gastric malignancy, mucosa-associated lymphoid tissue (MALT) lymphoma) and protective for oesophagus (Barrett's oesophagus, oesophageal adenocarcinoma) at the same time in an individual. For prevention of diseases, the necessity of presence of some bacteria throughout the gastrointestinal lumen needs to be emphasized. The concept--only good Helicobacter pylori is a dead Helicobacter pylori, is dangerous and humans should learn to live in harmony with a few bacteria throughout the gastrointestinal tract.