G Moens

Work-related Helicobacter pylori infection among sewage workers in municipal wastewater treatment plants in Belgium

Introduction Most studies among sewage workers of wastewater treatment plants (WWTPs) have found a higher prevalence of gastrointestinal symptoms than among non-sewage exposed workers. Waterborne transmission of Helicobacter pylori (H pylori) has been hypothesised, as the bacteria can survive into an aqueous environment and has been detected in sewage. A health and hygiene questionnaire has demonstrated a higher prevalence of peptic ulcers among Belgian WWTP operators and maintenance workers than among non-sewage exposed colleagues. Objectives To assess the seroprevalence of H pylori infection in Belgian sewage workers at municipal WWTPs, and to determine whether sewage exposure is an important risk factor for acquisition of H pylori and the possible association with gastrointestinal symptoms. Methods A seroprevalence study of H pylori antibodies was conducted among 317 WWTP employees (operators, maintenance workers, laboratory personnel, other job). Information about demographic variables, possible H pylori risk factors, working history, and history of current gastrointestinal symptoms during last 3u2005months was obtained by a questionnaire. The presence of H pylori IgG was investigated with an ELISA. The results were compared with those of 250 employees of a pharmaceutical company (operators, maintenance workers, laboratory personnel). Results The prevalence of H pylori IgG antibodies among sewage workers was 16.7% (95% CI 12.6 to 20.8%) compared to 13.6% (95% CI 9.4 to 17.8%) among the control group. In a logistic regression model with controlling for age and educational levels, OR study/control group was 1.02 (95% CI 0.58 to 1.80 with p=0.93). No significant associations were found between the H pylori status and gastrointestinal symptoms, occupational exposures in different tasks, nor with hygienic practices. Conclusions Our results do not suggest that H pylori infection is a probable cause of part of gastrointestinal symptoms among Flemish municipal sewage workers of WWTPs.

The occupational risk of Helicobacter pylori infection among workers in institutions for people with intellectual disability

Objectives: A cross-sectional study to evaluate the occupational risk for Helicobacter pylori infection, on top of other risk factors, in staff members of institutions for people with intellectual disability. In these institutions, the residents had a documented high prevalence of H pylori infection (86% presenting antibodies). As a control group, the study used administrative workers from other companies. Methods: All participants completed a questionnaire concerning sociodemographic characteristics, medical history and employment data and they underwent a serology test. Results: 671 staff members of the institutions and 439 subjects in the control group participated in the study. Prevalence of H pylori antibodies was significantly higher in the study group than in the control group (40.6% vs 29.2%; p<0.001). Crude odds ratio for occupational risk was 1.68; adjusting for the confounding effect of age, gender, body mass index, smoking, tropical journeys and number of household members during childhood resulted in an even higher (adjusted) OR of 1.98 (95% CI 1.42 to 2.69). In multiple logistic regression analysis adjusting for variables shown to be confounders, faecal contact continued to be significantly associated with H pylori infection. Attributable risk was 49.5%. Conclusions: H pylori infection is an occupational risk in healthcare workers working in institutions for people with intellectual disability. We identified faecal contact as an independent occupational risk factor for H pylori infection.