Helicobacter pylori is an important, transmissible, human pathogen aetiologically related to gastric cancer, peptic ulcer disease, atrophic gastritis, iron deficiency anaemia, vitamin B12 deficiency and idiopathic thrombocytopenia. Helicobacter pylori gastritis is an insidious disease that alters gastric physiology and causes progressive gastric mucosal damage. Typically, those affected only become aware of the infection when it expresses its presence by the development of clinical manifestations such as dyspepsia, a major upper gastrointestinal haemorrhage or an incurable gastric cancer. The infection is transmitted within families and is typically acquired in childhood. Helicobacter pylori is an opportunistic pathogen and takes advantage of any chance to gain access to the stomach,(ie, faecal-oral, oral-oral, contaminated water or food, etc.) where, once established, the infection is typically lifelong. Current consensus is that the presence of the infection confers only risk without any benefit to the host. 1 During the 19th and most of 20th centuries it was a major cause of disease being responsible for both peptic ulcer disease and gastric cancer. 2 Gastric cancer was the most common cause of cancer death until the last third of the 20th century and is still a major health problem worldwide. 3, 4 The prevalence of H. pylori infection inversely correlates with economic development as reflected in sanitation, clean water, poverty, socioeconomic status and, especially, household hygiene. In highly developed countries the prevalence of the infection has been declining since at least 1950 such that the infection is mostly confined to the elderly, those of lower socioeconomic status in childhood, and in immigrants from countries where the prevalence of the infection is still high. 2 Overall, it has been estimated that approximately one-half of the world’s population is infected. 5 The recognition that H. pylori infection provides no benefit and that its eradication could eliminate gastric cancer has resulted in a change in attitude toward the infection from the aim of identifying and curing it among those with symptoms (eg, uninvestigated dyspepsia) or complications (upper gastrointestinal bleeding) to be more proactive (Table 1). 3, 6, 7 All recent consensus groups agree that, whenever the infection is identified, it should be treated unless there are compelling reasons not to do so. 3, 6, 7 In addition, it is now recommended that testing for the infection should be extended to high risk populations, groups, and individuals including first degree relatives of those with H. pylori-associated diseases and those living in the same household6 (Figure 1).