While many are obsessed with finding the ‘source’ of their ‘Blasto’ or other friendly gastrointestinal parasites, less of us ask the same question and do the comparable detective work in cases of Helicobacter pylori, a bacteria that is estimated to inhabit the gut of over 50% adults worldwide and a surprising percentage of children. But we should. The transmission of H.pylori is accepted as being through person to person contact but the exact mode or route remains hotly debated. So if one individual tests positive what sort of things should be put in place to prevent sharing it with their loved ones? What are the other risk factors that can increase or reduce our susceptibility even in the face of such exposure? Should we even worry about its presence – is it simply a much much maligned and misunderstood commensal? It’s time to revisit this bacteria that has a long and fascinating history with humanity.