Peptic ulcer epidemiology and demographics

Overview
In Western countries the prevalence of Helicobacter pylori infections roughly matches age (i.e., 20% at age 20, 30% at age 30, 80% at age 80 etc). Prevalence is higher in third world countries. Transmission is by food, contaminated groundwater, and through human saliva (such as from kissing or sharing food utensils.)

According to Mayo Clinic, however, there is no evidence that the infection can be transmitted by kissing:

"No evidence indicates that this bacterial infection is transmitted by sharing food or kissing." (http://www.mayoclinic.org/peptic-ulcers/qanda.html)

A minority of cases of Helicobacter infection will eventually lead to an ulcer and a larger proportion of people will get non-specific discomfort, abdominal pain or gastritis. The prevalence of infection is greater in developing countries and is influenced by socioeconomic conditions, ethnic background and age. In the Philippines, there is scarcity of published data regarding the epidemiology of this bacterium. Locally unpublished reports revealed a prevalence of 5.6% seropositivity rate in children and 60% among 136 adult Filipino patients with dyspepsia using the Clotest® (Cabahug et. al. 2003 and Caballero et al., 1997,  unpublished data). A lower prevalence rate of 42% was reported by Daez et. al. in 2002 (unpublished data) among 375 patients undergoing endoscopy at the Philippine General Hospital utilizing the rapid urease test and histopathology.