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The prevalence of anti-HEV was assessed in 2,233 subjects aged 20-79 years in the Republic of San Marino in the years 1990-1991. The sera were tested by ELISA and further confirmed by Western blot (WB) analysis. The overall anti-HEV prevalence was 1.5%. A significant trend by age was observed. Anti-HEV prevalence was 0.6% in subjects <30 years and 3.3% in those older than 70 years of age. Family size larger than four persons (OR = 3.8; 95% CI = 1.8-13.2) was the sole independent predictor of anti-HEV positivity in the multivariate analysis. Anti-HAV and anti-HEV prevalences did not show a parallel trend by age. No association was found either between hepatitis E virus (HEV) or hepatitis C virus (HCV) infections. Follow-up samples 5 years apart were available for 38 out of 54 (70%) anti-HEV ELISA-positive subjects. Eight out of 22 (37%) WB-confirmed anti-HEV-positive subjects were still anti-HEV-positive after 5 years. However, anti-HEV remained positive in all but two (75%) of the subjects with WB-confirmed ELISA positivity value of S/CO > or = 2 (cutoff 1.2), but in only 2 out of the 14 subjects (14%) with a WB-confirmed ELISA positivity value of S/CO < 2 (P < 0.005). None of the 16 subjects ELISA-positive but not WB-confirmed was anti-HEV-positive 5 years apart. Therefore, only a relative proportion of subjects once infected with HEV maintain for at least 5 years anti-HEV antibodies.

Objective: To evaluate the role of faecal-oral transmission in the spread of Helicobacter pylori., Design: A cross-sectional comparison of the patterns of hepatitis A and H. pylori seropositivity., Methods: At interview, blood samples and questionnaire data were collected from a random sample of 1528 healthy subjects aged 20-85 years from the Republic of San Marino. Serum samples from each subject were then tested for anti-H. pylori and anti-hepatitis A antibodies., Results: Overall, 529 of 670 H. pylori-seropositive subjects (78.9%) and 460 of 858 H. pylori-seronegative subjects (53.6%) were hepatitis A seropositive (P<0.01; odds ratio=3.2; confidence interval 95%=2.6-4.1). This association remained after adjustment by a multiple logistic regression analysis for the confounding effect of age and length of schooling, as surrogate for socio-economic status (OR=2.0; CI 95%=1.3-3.3). The age-specific prevalence curves for H. pylori and hepatitis A infections showed a parallel increase by age, although to a lesser extent for H. pylori., Conclusion: These findings provide evidence that in the community studied H. pylori may have spread in a manner similar to that of hepatitis A.

In 1990-1991, the prevalence of antibodies to hepatitis A virus infection (anti-HAV) was assayed by the ELISA method among 1528 apparently healthy subjects, 20-85 years old in the Republic of San Marino. Subjects were selected from the list of residents by a random stratified sampling procedure with a proportional allocation by age, sex and district of residence. The overall anti-HAV prevalence was 64.7%; it increased from 28.6% in subjects 20-30 years old to 97% in those > 60 years (p < 0.01). No gender difference was observed. At the multivariate analysis age > 40 years (OR: 39.5; 95% CI: 12.4-126) and lowest level of schooling (OR: 1.8; 95% CI: 1.1-2.9), which is a good indirect indicator of socio-economic status, resulted both independent predictors of anti-HAV seropositivity. These findings reflect the improved sanitation standards in this area and indicate that the proportion of non-immune adults is increasing with a higher risk of symptomatic infection in the near future.

Helicobacter pylori is present worldwide but few large population studies exist on the epidemiology of the infection. A random cross sectional study was performed of H pylori infection in the adult population of San Marino, a European country with high gastric cancer rate, to assess its prevalence and to evaluate its relations with gastrointestinal disease. In 2237 subjects (77% of the initial sample) H pylori IgG antibodies were detected with enzyme linked immunosorbent assay (ELISA) and immunoblotting. A questionnaire including questions about occupation, place of birth, and smoking was given to all subjects. Dyspepsia, peptic ulcer, and gastric cancer in the subjects, relatives, and partners as well as use of drug, dental treatment/prostheses, and gastrointestinal endoscopies, were evaluated by multivariate analysis. H pylori prevalence was of 51%, increased with age from 23% (20-29 years) to 68% (> or = 70 years), and was higher among manual workers. H pylori was independently associated with ulcer (OR = 1.63, 95% confidence intervals (CI) = 1.16 to 2.27), H2 antagonists (OR = 1.94, 95% CI = 1.21 to 3.10), and benzodiazepines (OR = 1.57, 95% CI = 1.02 to 2.42), dental prostheses (OR = 1.25, 95% CI = 1.05 to 1.49), gastroscopy in the past five years (OR = 1.50, 95% CI = 1.05 to 2.14), peptic ulcer in siblings (OR = 1.52, 95% CI = 1.09 to 2.12), gastric cancer in father (OR = 1.61, 95% CI = 1.02 to 2.52). The association of seropositivity with history of ulcer, gastric cancer in family, gastroscopy, and H2 antagonists suggests that H pylori is an epidemiological key factor in the pathogenesis of gastroduodenal diseases in this area.