Helicobacter infection: What should a swine practitioner know?

Gastric microbiology of the pig has been given a great deal of attention in the past decade. Much of the work in this area has been published in human medical journals, and therefore, swine practitioners may not be aware of these recent findings. The pig has been used in the study of gastroduodenal ulcers of humans. The stomach of pigs has been successfully colonized experimentally by Helicobacter pylori, the bacterium associated with gastric ulceration and gastritis in humans. Although H. pylori does not naturally inhabit the pig’s stomach, there are spiral-shaped bacteria that can commonly be found in the porcine gastric mucosa. This bacterium has been tentatively named Helicobacter heilmannii (formerly Gastrospirillum suis). Helicobacter heilmannii is found in several other species, including dogs, cats, and occasionally humans. Survey studies show that pig contact is an important risk factor for humans becoming infected with H. heilmannii. Infection of humans with H. heilmannii causes a milder form of chronic gastritis than H. pylori and may be self-limiting. At the present time, it is unclear whether H. heilmannii infection of swine causes disease. In swine, the site of ulceration is in the pars oesophagea whereas H. heilmannii colonizes the fundic and pyloric regions. Pigs experimentally infected have not developed gastric ulcers; however, several epidemiological studies have found a strong association between the presence of H. heilmannii and ulceration of the pars oesophagea. Practitioners need to consider this organism as a potential pathogen and a potential zoonotic bacterium.