Prevalence of Helicobacter pylori in asymptomatic subjects--a nested PCR based study.

The aim of the study was to see the prevalence of Helicobacter pylori in asymptomatic children and adults by using nested PCR which is considered to be more specific than serological methods. Saliva and stool samples of 137 healthy children (aged 8 months to 16 y) and 108 asymptomatic adults (aged 17-60 y) were collected. PCR with primers targeting Hsp60 gene sequence of H. pylori was used. H. pylori positivity with nested PCR was observed in 45.7% (112/245) of the saliva and 42.8% (105/245) of the stool specimens. Prevalence of H. pylori in saliva was found to be 2.1%, 22.7%, 55.9%, 56.0%, 68.9% and 62.9% in the age groups of < 5 y, 6-10 y, 11-16 y, 17-30 y , 31-45 y and 45-60 y, respectively. The detection rates in stool were 4.25% in < 5 y, 13.64% in 6-10 y, 50% in 11-16 y, 64% in 17-30 y, 58.62% in 31-45 y and 61.1% in 45-60 y of age groups. The most favourable age group for acquiring the infection was 11-16 y. H. pylori positivity increased with lowering of socioeconomic status. There was no gender bias in prevalence of the bacterium.