Biofilms in drinking water systems - A possible reservoir for Helicobacterpylori

Helicobacter pylori is a major bacterial pathogen involved in several gastr ointestinal diseases. Transmission routes and reservoirs of H pylori are no t well understood despite several studies. In contrast to many other infect ious diseases, clinical symptoms allowing definitive diagnosis of infection are absent. Person-to-person transmission with faecal-oral and oral-oral r outes have been proposed with socio-economic status and density of living a s associated factors. Studies have shown that H pylori can survive in water for prolonged periods leading to a waterborne transmission route being pro posed but not conclusively identified. This paper describes studies using m ature heterotrophic mixed-species biofilms grown under oligotrophic conditi ons using a continuous-culture chemostat system. The biofilms were challeng ed with Helicobacter pylori (NCTC 11637). Results indicate the presence of H pylori associated with the biofilm for up to 192h post-challenge, suggest ing that biofilms in water distribution systems could be a possible and as yet unrecognised reservoir of H pylori. (C) 1998 Published by Elsevier Scie nce Ltd on behalf of the IAWQ. All rights reserved.