Gisela J. Fritz

Helicobacter pylori colonisation and eczema

The hygiene hypothesis postulates that the increase in atopic diseases may in part be due to diminished exposure to microorganisms. But it is unknown which type of infection does render protection. An epidemiological study was conducted in Leipzig, Germany, and its rural county, involving 3347 school starters. Two types of infection were considered: (1) gastrointestinal colonisation (Helicobacter pylori detection using in vivo [13C] urea breath test) and (2) respiratory infections (physician-diagnosed lower (bronchitis) and upper (common cold) respiratory infections). H pylori colonisation was selected because it is very common and plays an important role in gastrointestinal disorders. Atopic eczema was selected as the (allergic) target variable because of its high frequency in the age of the study participants. The results, adjusted for relevant confounders, showed a significant inverse association between H pylori infection and eczema (adjusted odds ratio (aOR) = 0.31, p = 0.006) in children not predisposed to atopy. In contrast, bronchitis increased the risk of eczema (aOR = 1.98, p<0.001). Bacterial digestive tract colonisation (infection) seems to protect against eczema in comparison with the effect of respiratory tract infections. The hygiene hypothesis may be better explained when gastrointestinal and respiratory infections are subtly differentiated.

Well water--one source of Helicobacter pylori colonization.

Helicobacter pylori (H. pylori) is one of the worlds most widespread microorganisms. Its acquisition in humans remains poorly understood, however, epidemiological studies have identified drinking water as reservoir for the bacterium. The aim of this study was to investigate the prevalence of H. pylori infection among individuals using or drinking previously H. pylori tested well water. Applying household cluster sampling, a total of 91 subjects, all using or drinking well water (13 of either H. pylori positive or negative wells), were screened for their H. pylori status. The group was comprised of 73 adults and 19 children under the age of 18. H. pylori infection was determined using the [13C]urea breath test. A self-administered or parent-completed questionnaire provided information on living conditions and lifestyle habits including the use or drinking of well water. Logistic regression analyses associated the drinking of H. pylori positive well water with a positive colonization status [Odds Ratio (OR) 8.3; 95% confidence interval (95% CI) 2.4-29]. In summary, the use or drinking of H. pylori contaminated well water appears associated with the acquisition of a H. pylori infection. This study is based on a relatively small and inhomogeneous population sample and should be repeated to confirm the results.

Helicobacter pylori determination in non-municipal drinking water and epidemiological findings

Background. Studies conducted in Europe as well as in North and South America have tried to link Helicobacter pylori colonization with the drinking water supply, especially since H. pylori is known to survive quite well in water. Methods. In 2000, a cohort of 1884 grade-two children from two rural counties surrounding the city of Leipzig, Germany (77.4% of the 1991/1992 birth cohort) were tested for H. pylori colonization using the [13C]urea breath test. A parent-completed questionnaire elicited details on living conditions and lifestyle habits including questions on the childrens drinking water from sources other than public water supplies, swimming in natural waters, etc. In a second independent study, samples of well water, taken from 157 private wells still used in the two counties, were being tested for the presence of H. pylori, using polymerase chain reaction (PCR) method to determine relevant target DNA fragments of H. pylori. Results. In county I, 5.7% of the children and in county II 6.6% tested H. pylori-positive. Cluster analyses of the questionnaire data in both counties pointed to ‘drinking water from other than municipal sources’, as the closest H. pylori-associated cluster variable. The cluster estimations were supported by odds ratio (OR) calculations with an OR = 16.4 (95% confidence interval (CI) 3.1,…,88.5) for county I and OR = 4.0 (95% CI 1.3,…,12.4) for county II. The PCR analyses showed H. pylori DNA fragments in 10.8% of the wells in county I and 9.2% in county II. The detection limit was set at 10 DNA copies corresponding to 125 bacteria/L, the average infestation of these wells was 931 bacteria/L. Conclusion. Despite the fact that the microbiological and epidemiological data do not correspond except that both studies were conducted in the same geographical areas, the independent findings of H. pylori in well water in the same general areas where children do seem to drink water other than from the public water supply suggests that water may be an important source of H. pylori infection.

Pollution profiles at different kindergarten sites in Leipzig, Germany

Between Jan. and Dec. 1994, the outdoor air quality of the city of Leipzig, Germany, was examined at 13 kindergartens. SO2, CO, NOX, O3, total suspended particles, sedimentation dust and volatile organic compounds were measured. Although each monitoring site appears to have its own individual pollutant profile, two general pollution profiles could be identified using principal component analysis. These profiles are largely attributable to two dominant emission sources, domestic heating and traffic. Indicator components were identified for both pollution profiles. Benzene was found to be the indicator component for traffic and SO2 for domestic heating. The predominating types of pollution are reflected in the prevalences of respiratory diseases among 311 children investigated based on parent‐completed questionnaires. High traffic pollution was found to be associated with an increased occurrence of asthma and allergies and domestic heating with bronchitis. ©1999 John Wiley & Sons, Inc. Environ Toxicol 14: 321–327, 1999

Helicobacter pylori prevalence in Leipzig’s 1998 school entries: methodology and first results

The non-invasive, stable-isotope-aided Helicobacter pylori (H. pylori) tests--breath and equivalent urine tests--were offered on a voluntary basis as part of the mandatory school entry medical examination to the 1998 school entry cohort of the City of Leipzig (480,000 residents). Parents of participating subjects were asked to fill out a detailed epidemiologic questionnaire. The response rate was 94% (n = 2228 of 2369 school starters born in 1991/92). Parent-completed questionnaires were returned by 1890 (80%) children. The overall H. pylori positive prevalence was 7.2%. The prevalence among children with a test and a parent-completed questionnaire was 6.5%. Prevalences among subsequently tested family members of the positive tested children was 65, 60 and 39% for mothers, fathers and siblings respectively. Though studies have shown that the direct transmission of the bacterium (oral-oral and fecal-oral) is a dominant pathway of infection, the questionnaire analyses indicate associations between H. pylori colonisation and living as well as environmental conditions.