Helicobacter Pylori: The Organism, the Disease, the Clinical Picture, the Current Research
In infected patients, 30%-35% have no symptoms.
Peptic ulcer disease and gastric cancer are indeed very ancient diseases, but because the number of cases related to these diseases was insignificant until the second half of the 18th century they have been suggested to be modern diseases. However, increased life expectancy in new industrialized countries, specifically the UK and US, may explain the escalation of peptic ulcer disease and gastric cancer cases. Several studies indicated major changes in life expectancy, from less than 45 years in the 18th century to more than 60 years by the 19th century in the same countries.
In 1985, for example, Marshall underwent gastric biopsy to put evidence that he didn't carry the bacterium, then deliberately infected himself to show that it in fact caused acute gastric illness. How long humans carried H. pylori is still a debatable issue. However, it is accepted that this organism has colonized humans possibly for many thousands of years, and the successful persistence of H. pylori in human stomach for such a long period may be a case to conceive that this organism is advantageous to its host (Chow WH, Blaser MJ, 1998).
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