Decreasing seroprevalence of Helicobacter pylori infection during 1993-2003 in Guangzhou, southern China

BACKGROUND: Prevalence of Helicobacter pylori infection is inversely associated with socioeconomic conditions. The aim of the study was to evaluate changes in the seroprevalence of H. pylori infection during 1993-2003 in Guangzhou, a representative city of southern China with quick improvement in socioeconomy. METHODS: From March to August 2003, sera were collected from 1471 healthy persons (760 male and 711 female subjects, aged 3-92 years) undergoing annual routine health examination in Guangzhou. H. pylori infection was checked by enzyme-linked immunosorbent assay (ELISA). RESULTS: In 2003, the overall prevalence rate of H. pylori infection was 47% with no gender difference (p > .05). Children aged 1-5 years had the prevalence rate of 19.4%. The prevalence rate then increased steadily with annual infection rate of approximately 1% after this age, reaching a plateau of approximately 55% after the age of 50 years. The peak seroprevalence rate was 63.2% at 40-50 years. Comparing the prevalence rate of H. pylori infection in 2003 with data obtained in 1993, statistically significant decrease of H. pylori infection rate ranged from 11.4 to 18.0% in different age groups was found. The overall age-standardized H. pylori seroprevalence rate was 62.5% in 1993 and 49.3% in 2003. The seroprevalence of H. pylori was found to be significantly decreased over a time span of 10 years (p < .001). CONCLUSIONS: Our data suggest that the seroprevalence of H. pylori infection has significantly decreased during the 10-year period in Guangzhou. This change may be attributable to the improvement in socioeconomic conditions in this city.