Which of the following patient is most likely to harbor a Helicobacter pylori infection in the stomach?
The most important risk factors for H. pylori infection include older age, low income, and residence in a developing country. It is believed that infection generally is acquired in childhood. Although humans are the major reservoir of H. pylori, the route of infection is unclear, with fecal-oral and oral-oral spread both being possible. H. pylori is endemic in only 30% of Americans, but prevalence rates are as high as 80% in developing countries. Infection with a related species, H. heilmanii, is about 1% as common as H. pylori infection.
A 60-year-old middle-income American
A 25-year-old American in a low-income group
A 25-year-old Zairian
A 60-year-old Pakistani