red blood cells illustration of microscopic photos
This Gram-negative bacillus bacterium is curved (as here) or spiral in shape, with flagellae for motility. Here, many hair-like flagellae are visible. Colonies of H.pylori occur on the stomach mucous membrane in people suffering gastritis, and this bacteria has been linked to stomach ulcer formation. H.pylori may also be a co-factor for gastric cancer; its presence increases the risk of stomach tumours.