◆Discovered by: Barry J. Marshall The discovery was made by Barry J. Marshall and J. Robin Warren. In 1979, Warren, a pathologist, observed a curved bacterium on a section of mucosal tissue from the gastric sinus of a patient with chronic gastritis and found that the gastric mucosa adjacent to the bacterium was always inflamed, thus realizing that the bacterium and chronic gastritis might have a close relationship. The close relationship between this bacterium and chronic gastritis was recognized. In 1981, gastroenterology clinicians Marshall and Warren collaborated on a study of 100 patients with gastric disease who underwent gastroscopy and biopsy and demonstrated that the presence of this bacterium was indeed associated with gastritis. In addition they found that this bacterium was also present in the gastric mucosa of all patients with duodenal ulcers, most patients with gastric ulcers, and about half of those with gastric cancer. After many failed attempts, Marshall finally succeeded in culturing and isolating the bacterium from a gastric mucosal biopsy sample in April 1982. To further confirm that this bacterium was the culprit of gastritis, Marshall and another doctor, Morris, drank the culture containing the bacterium and became very ill. Based on these results, Marshall and Warren proposed that H. pylori was involved in the etiology of gastritis and peptic ulcers, and on April 5, 1984, their results were published in the world’s leading medical journal, The Lancet. Once the results were published, they immediately caused a sensation in the international gastroenterology community and set off a worldwide research boom. Major pharmaceutical companies around the world invested heavily in the development of related drugs, the journal Helicobacter was created, and the World Helicobacter Congress was held regularly, with countless research papers on Helicobacter. Through human trials, antibiotic therapy and epidemiological studies, the role of H. pylori in diseases such as gastritis and gastric ulcers is becoming clearer and scientists are gaining a better understanding of the pathogenic mechanism of the bacterium. On October 3, 2005, the Karolinska Institute in Sweden announced that the 2005 Nobel Prize in Physiology or Medicine had been awarded to the two scientists for their discovery of H. pylori and the role of the bacterium in diseases such as gastritis and gastric ulcers. After many failed attempts, Marshall finally succeeded in culturing and isolating the bacterium from a gastric mucosal biopsy sample in April 1982. To further confirm that this bacterium was the culprit of gastritis, Marshall and another doctor, Morris, drank the culture containing this bacterium and became very ill as a result.