A method for survey of natural waters and soils for Pseudomonas pseudomallei was devised, and it was tried in sampling a tin-mining pool area near Kuala Lumpur, Malaysia. The method consisted of intraperitoneal inoculation of weanling hamsters with either 2.0 ml of natural waters, or 1.0 ml of supernatant fluid from sedimented suspensions of soil. Subsequent cultural study was made only of animals dying after inoculation. A differential bacteriologic medium was used, composed of nutrient agar with 3% glycerol and 1:200,000 crystal violet added. The method is sensitive: fewer than 10 organisms regularly killed hamsters. The method is fast: average time of death was 3 days after inoculation, with a range of 2 to 5 days for 96% of animals.
Captain, Veterinary Corps, U. S. Army. Present address: Fort Worth, Texas.
Colonel, Medical Corps, U. S. Army. Present address: Armed Forces Institute of Pathology, Washington, D. C.