The authors of the study suggest that treatment and prevention strategies should therefore be targeted at young children.
H. pylori infection is associated with many gastrointestinal disorders, including gastritis, gastric ulcer, duodenal ulcer, gastric carcinoma, and primary gastric-cell lymphoma.
H. pylori is common worldwide, but the age at which it is acquired is unclear.
Hoda Malaty and colleagues from Baylor College of Medicine, Houston, USA, studied 224 children (99 black, 125 white; 110 male, 114 female) from 1975-76 (ages 1-3 years) to 1995-96.
It was found that 18 (8%) children at age 1-3 years had H. pylori antibodies (13% black compared with 4% white children).
By age 18-23 years, the prevalence of the infection was 24.5% (43% black compared with 8% white participants).
|8% of children at age 1-3 years had H. pylori antibodies.
Of the 206 children not infected at the start of the study, 40 (19%) became infected by age 21-23.
The crude incidence rate per year was 1.4%, ranging from 2.1% at age 4-5 years and 1.5% at 7-9 years, to 0.3% at 21-23 years.
Black children were more than three times more likely to have H. pylori infection, although the average age of acquisition at about 7.5 years was the same for both black and white children.
Hoda Malaty comments, "This study confirms that even within the same community, different cohorts can have different risks of acquiring the infection.
"Race had an important effect on the acquisition, persistence, and clearance of the infection, whereas sex had no significant effect.
"H. pylori infection was acquired at any time between infancy and young adulthood, but early childhood seems to be the important period when most of the infections are acquired.
"The period in life when the infection is acquired might also affect risk of development of forms of the infection with symptoms such as peptic ulcer, gastric cancer, or primary gastric B-cell lymphoma."