In 1979, Marshall was appointed as a Registrar in Medicine at the Royal Perth Hospital. He met Robin Warren, a pathologist interested ingastritis, during internal medicine fellowship training at Royal Perth Hospital in 1981. Together, the pair studied the presence of spiral bacteria in association with gastritis. In 1982, they performed the initial culture of H. pylori and developed their hypothesis related to the bacterial cause of peptic ulcer and gastric cancer. It has been claimed that the H. pylori theory was ridiculed by the establishment scientists and doctors, who did not believe that any bacteria could live in the acidic environment of the stomach. Marshall has been quoted as saying in 1998 that “(e)veryone was against me, but I knew I was right.” On the other hand, it has also been argued that medical researchers showed a proper degree of scientific skepticism until the H. pylori hypothesis could be supported by evidence.
After failed attempts to infect piglets in 1984, Marshall, after having a baseline endoscopy done, drank a Petri dish containing cultured H. pylori, expecting to develop, perhaps years later, an ulcer. He was surprised when, only three days later, he developed vague nausea and halitosis, (due to the achlorhydria, there was no acid to kill bacteria in the stomach, and their waste products manifested as bad breath), noticed only by his mother. On days 5–8, he developed achlorydric (no acid) vomiting. On day eight, he had a repeat endoscopy and biopsy, which showed massive inflammation (gastritis), and H. pylori was cultured. On the fourteenth day after ingestion, a third endoscopy was done, and Marshall began to take antibiotics. This story is related by Barry Marshall himself in his Nobel acceptance lecture Dec. 8, 2005, available for viewing on the Nobel website. Interestingly, Marshall did not develop antibodies to H. pylori, suggesting that innate immunity can sometimes eradicate acute H. pylori infection. Marshall’s illness and recovery, based on a culture of organisms extracted from a patient, fulfilledKoch’s postulates for H. pylori and gastritis, but not for peptic ulcer. This experiment was published in 1985 in the Medical Journal of Australia, and is among the most cited articles from the journal.
After his work at Fremantle Hospital, Marshall did research at Royal Perth Hospital (1985–86) and at the University of Virginia, USA (1986–Present), before returning to Australia while remaining on the faculty of the University of Virginia. He held a Burnet Fellowship at the University of Western Australia (UWA) from 1998-2003. Marshall continues research related toH. pylori and runs the H. pylori Research Laboratory at UWA.
In 2007, Marshall accepted a part-time appointment at the Pennsylvania State University.
In 2005, the Karolinska Institute in Stockholm awarded the Nobel Prize in Physiology or Medicine to Marshall and Robin Warren, his long-time collaborator, “for their discovery of the bacterium Helicobacter pylori and its role in gastritis and peptic ulcer disease”.
