Helicobacter Pylori Transmission and Risk Factors for Infection in Rural China

Helicobacter pylori H. pylon is one of the most common bacterial infections among humans, but little is known about its mode of transmission. A cross-sectional study of 3288 adults aged 35-69 from Shandong Province, China was conducted to assess some possible risk factors that may be associated with H. pylori infection in this high prevalence area of China. In-person home interviews lasting approximately 15 minutes were conducted in Chinese from October 1997-May 1998. The response rate was 96.4. Maximum likelihood estimates and bootstrap confidence intervals CI of the association between the prevalence of H. pylori infection and demographic, lifestyle and some common environmental exposures were computed using polychotomous logistic regression. The H. pylori serostatus of the study participants was positive 60.6Al, negative 31.0, and indeterminate 8.4. Source of drinking water, especially water from a shallow village well OR1.8, 95CI1.4-2.3, was associated with increased prevalence of H. pylori infection. ORs were also elevated for infrequent hand washing before meals OR1.6, 95CI1.0-2.5 and bathing in a pond or ditch OR1.6, 95CI1.0-2.4. ORs were also associated with median village education level, ranging from 1.0 for villages classified as high, to 1.7 95 CI1.4-2.1 for villages classified as medium. to 2.4 95CI2.0-3.0 for villages classified as low. ORs decreased slightly with increased consumption of all allium vegetables combined. The ORs were reduced for having a cat as a pet during childhood OR0.7, 95CI0.5-1.0 andor adulthood OR0.6, 95CI. No significant associations were seen with any measure of cigarette smoking or alcoholic beverage consumption. Additionally. crowding or density factors as a child were not related to a higher prevalence of H. pylori infection as an adult.