Helicobacter pylori infection among Japanese children

Background: In Japan, there are few reports describing Helicobacter pylori infection among young children. The aim of the present study was to identif y risk factors associated with H. pylori in school-aged children. Methods: Subjects were first-grade students of three elementary schools (n= 310) and second-grade students of a junior high school (n=300). Personal in formation, such as student's medical history, parent's history, family size , sibshipsize and household pets, was collected from guardians using a ques tionnaire. Saliva samples and personal information were collected twice (19 95 and 1996). By using the saliva samples, H. pylori IgG antibody was measu red using a commercial kit. To analyze the risk factors for n. pylori infec tion, sex- and age-adjusted odds ratios (OR) were calculated using a multip le logistic model. Results: Among the children, factors related to Helicobacter antibody in sa liva included spending a longer period of time in a nursery school or kinde rgarten (OR = 4.0) and a maternal history of stomach disease (OR = 2.8). Bi rth order (OR = 2.2), sleeping situation (OR = 2.3) and sibshipsize (OR = 1 .6) were not factors that were significantly related to Helicobacter antibo dy in the saliva. Chewing food for the infant, family size, rooms in the ho usehold, sharing a bedroom during childhood, pets, a past history and a pat ernal history were nor related to positivity Conclusions: The results indicate that transmission is person-to-person, ma inly through close contact with other children and intrafamilial infection. Helicobacter pylori infection seems to occur frequently early in life, pro bably before 6 years of age. (C) 2000 Blackwell Science Asia Pty Ltd.