In 1984 a Western Australian scientist, Dr Barry Marshall, discovered the link between "Helicobacter pylori" (at that time known as "Campylobacter pylori") and gastritis. This was based on a series of self-experiments that involved gastroscopy and biopsy, ingestion of "H. pylori", regastroscopy and biopsy and subsequent treatment with tinidazole. His only option was self-experimentation: ethical measures forbade him from administering "H. pylori" to any other person. In 2005, Marshall and his long-time collaborator Robin Warren were awarded Nobel Prize in Physiology or Medicine, "for their discovery of the bacterium "Helicobacter pylori" and its role in gastritis and peptic ulcer disease".