| country-specific constancy by age in caga+ proportion of helicobacter pylori infections. | helicobacter pylori strains may be either caga+ or caga-, and in logitudinal studies, infection with a caga+ strain has been associated with increased risk for the development of atrophic gastritis and cancer of the distal stomach. we sought to determine the relative proportion of strains producing caga in different geographic locales, and the extent to which caga seroprevalence varied in countries with different gastric and esophageal cancer rates. using an enzyme-linked immunosorbent assay (el ... | 1997 | 9247289 |