Abstract. Helicobacter pylori is associated with chronic antral gastritis that is related to duodenal ulcer, gastric ulcer, and probably gastric adenocarcinoma. Infection with H. pylori during childhood is considered an important risk factor for gastric carcinoma in adult life. To examine the epidemiologic characteristics of H. pylori infection among preschool children in central Taiwan, a community-based survey was carried out in 54 kindergartens in 10 urban townships, 10 metropolitan precincts, and 2 aboriginal townships randomly selected through stratified sampling. Serum specimens of 2,551 healthy preschool children (3-6 years old) randomly sampled from study kindergartens were screened for antibodies to H. pylori by latex agglutination and ELISA methods. Multivariate-adjusted odds ratios (ORs) with their 95% confidence intervals (CIs) were estimated by multiple logistic regression analysis. A total of 207 subjects were antibody-positive, giving a prevalence of 8.1%. The overall seropositive rates were 4.5% in 3-year-old group, 4.4% in 4-year-old group, 9.4% in 5-year-old group, and 11.7% in 6-year-old group. The older the age, the higher the seroprevalence (OR ϭ 3.2, 95% CI ϭ 1.5-6.8 for 3-year-old children versus the 6-year-old children). Seroprevalence was not different between boys and girls. The aboriginal townships had a seroprevalence greater than the urban townships and metropolitan precincts (OR ϭ 2.6, 95% CI ϭ 1.9-3.7). The larger the number of siblings, the higher the seroprevalence (OR ϭ 2.4, 95% CI ϭ 1.0-5.8 for those with no sibling versus those with Ն 3 siblings). In the multiple logistic regression analysis, the seroprevalence of H. pylori remained significantly increased with age, aboriginal township, and large sibship size after multivariate adjustment. A poor water supply system, sewage disposal, and other environmental hygiene in the aboriginal townships might have played some role in infection with H. pylori. The early childhood transmission among siblings might also be an important determinant of H. pylori seropositivity in Taiwan.Infection with Helicobacter pylori has been causally related to chronic gastritis and peptic ulcer, and indirectly related to gastric adenocarcinoma and primary gastric B cell lymphoma.

Abstract. Helicobacter pylori and hepatitis A virus (HAV) are documented to share common transmission routes including fecal-oral. This study examined the association between seropositivity of antibodies against H. pylori (anti-HP) and HAV (anti-HAV) via a community-based survey of 40 randomly selected kindergartens in 10 urban and 10 rural areas. Serum samples from 2,047 healthy preschool children and 104 teachers were screened for anti-HP by enzyme-linked immunosorbent assay, and for anti-HAV by microparticle enzyme immunoassay. In children, a low prevalence of anti-HAV (0.44%) was found, in contrast to a high prevalence in their teachers (78.8%); anti-HP seroprevalence was 6.4% for children and 30.8% for teachers. Anti-HAV and anti-HP seropositivities were significantly associated in teachers after adjustment for age, sex, and residential area through multiple logistic regression analysis (multivariate-adjusted odds ratio ϭ 7.3; 95% confidence interval [CI] ϭ 1.4-36.8, P Ͻ 0.001). Our findings suggest that HAV and H. pylori may have shared transmission routes in central Taiwan 15 years or more ago, but not any recently.