Prevalence of Helicobacter pylori infection among sewage workers

An increased risk for gastric cancer among sewage workers has been described in several studies. During the last decade the bacterium Helicobacter pylori has emerged as one important risk factor for gastric cancer and is now considered a class I carcinogen by the International Agency for Research on Cancer. The route of transmission for this bacterium remains unclear, but fecal-oral transmission has been proposed. If true, this might entail a yet undescribed risk for sewage workers.

The prevalence of immunoglobulin G (IgG) antibodies against H pylori was studied with a cross-sectional study design in a group of 289 municipal workers. Samples of serum from 151 sewage workers at 11 sewage plants in Sweden and of serum from 138 referents were analyzed. The referents were group matched for age and socioeconomic status.

The prevalence of IgG antibodies against H pylori among sewage workers did not differ from that of the referents. The adjusted odds ratio (adjOR) was calculated from a logistic model with age and residence as confounding variables (adjOR 0.90, 95% confidence interval 0.53-1.5). The previously described increase in the prevalence of IgG antibodies against H pylori with increasing age was observed. Geographic differences were also observed in the prevalence of H pylori in Sweden.

The exposures in sewage work in Sweden do not cause an increased risk of infection with H pylori.