Optimal survival of Helicobacter pylori under various transport conditions.

The ability of clinical isolates and type strains of Helicobacter pylori to survive in Stuart transport medium, isotonic saline solution, and urea-containing isotonic saline was evaluated. The influences of temperature (4, 10, 15, 20, and 30 degrees C) and holding time (6 to 48 h) and the effect of exposure to air on survival were also studied. The recovery rate of H. pylori was highest from Stuart transport medium in comparison with the recoveries from the other transport media tested. We found that at holding temperatures above 15 degrees C the organisms became noncultivable within 6 h or less, while they survived for 2 days or longer at 10 degrees C. The presence of urea at a concentration of 2% (wt/vol) in isotonic saline resulted in the loss of viability of the organisms tested.