In most cases, the first H. pylori infections occur in infancy and childhood (mostly before the age of 10 years), and infections after adulthood are relatively uncommon (but do exist). The main source of infection may come from family members, such as parents, siblings, etc. The transmission route is generally oral-oral and fecal-oral, and intimate contact, consumption of contaminated food and drinking water are all possible routes of transmission. Foreign studies have found that the detection rate of H. pylori in urban drinking water is 4%, and it can also be detected on the surface of food such as vegetables. Once infected, if left untreated, H. pylori may stay with you for the rest of your life.