The relationship between H. pylori and diseases of gastroduodenal mucosa has been well established. Previous studies suggested a fecal-oral transmission which should place health care personnel who are in close contact with patients at a higher risk. This study was conducted on two groups, the first consisted of 50 medical personnel (28.12 +/- 10.6 years) [34 doctors (30.1 +/- 3.2 years) and 16 nurses (25 years)]. The second consisted of 33 adult healthy volunteers who served as a control group (32.1 +/- 10.6 years). There was high prevalence rates of H. pylori among medical personnel (86%) as well as normal controls (90.9%). H. pylori colonization increased with age in both groups. H. pylori antibody positive doctors had a significantly longer duration of work than H. pylori antibody negative ones (P < 0.05). The prolonged duration of work in medical personnel increased H. pylori antibody positivity. Also, H. pylori antibody positive nurses had a significantly shorter duration of work--i.e. need less time to acquire positivity--than H. pylori antibody positive doctors (P < 0.05). From this study we conclude that H. pylori antibody positive status is very common in both medical personnel and normal population. The longer the duration of exposure to patients in medical personnel the higher the possibility to acquire H. pylori antibody positivity. However, doctors need more years of contact than nurses to acquire H. pylori antibodies.