1981 Volume 55 Issue 6 Pages 439-446
Legionella pneumophila, serogroup I were isolated from water samples in eight of eleven cooling towers in both Nagasaki University and municipal hospital on October, 1980.
They are the first isolation from environmental sample in Japan. The cooling towers were used for the air-conditioning systems of both hospitals.
We used a modification of the system for detection of L. pneumophila described by Morris and associates (Ann. Int. Med., 1979). The cooling tower water for detection of L. pneumophila was collected aseptically in the sterile contrifuge tubes (250 ml each) from the collecting pan of thecondenser.
The sample was centrifuged at high speed (10, 000 rpm) for 20 min. and its supernatant was discarded with remainning the sediment in volume of 10 ml.
Three guinea pigs were inoculated intraperitoneally with each 3 ml of a sample, and sacrificed at 4 days after inoculation.
The lung, liver and splenic tissue, blood and peritoneal swab were used for direct fluorescent antibody (DFA) examination and culturing. All eight isolates had typical appearance on B-CYE agar, failed to grow on blood agar and yielded typical patterns of biochemical properties.
Four of eight isolates were confirmed with cellular fatty acids by gas-liquid chromatography. These strains were also sent to both Center for Disease Control (CDC, Atlanta) and Wadsworth VA Medical Center (Los Angeles) in U. S. A. and finally identified as L. pneumophila serogroup I.
