Grant: Travel Awards - Institute Community Support

Helicobacter pylori (H.pylori) are bacteria that infect the lining of the stomach. H.pylori is found all over the world, but some populations are more affected by the infection and related disease than others. Initial infection typically occurs during childhood and can persist life-long in the absence of treatment. Chronic infection is associated with inflammation of the stomach lining and rarely serious stomach disease, including peptic ulcers and stomach cancer. This research examines the role of the environment in transmission of H.pylori and development of related disease in Canadian Arctic communities, where 58-70% of tested residents have the infection. Residents if Aklavik, NT and Tuktoyaktuk, NT took part in a community-based research project on H.pylori infection in 2007 and 2011, respectively. Participants were tested for the infection and data on demographics, medical history and frequency of exposure to environmental sources were collected through structured interviews. Stomach biopsies were obtained in 2008 in Aklavik and examined through a microscope for signs of inflammation, graded as none, mild, moderate or severe. The frequencies of the infection and severe inflammation were compared between people who were and were not exposed to environmental sources using statistical models. Results indicate that the infection does not occur more frequently in individuals exposed to environmental sources that could potentially be contaminated with the bacteria, relative to participants who were not exposed to these sources. This includes environmental exposures such as untreated water, sewage, cats and dogs. Preliminary analysis of the effect of exposure to mice indicates that prevalence of H.pylori infection is higher in individuals who reported having mice in their home, relative to those who are not exposed to mice. This analysis also provided evidence of a possible link between untreated water consumption and prevalence of severe gastritis.