Gebäude 21, 1. OG
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In order to detect the possible health danger caused by Legionellae tohumans and animals, 300 water samples taken from various taps were examinedin the Laboratory Animal House of the University of D?sseldorf.Cause for an experiment of this kind was the fact that the veterinarystaff who had to pass sluices up which germ-free rodents live sufferedfrom severe colds.Tested were the drains that distribute municipal water, the condensate ofair conditioners and sterilizers as well as the ozonised with hydrochloricacid (HCL) soured drinking-water of the animals.M.W.Y.-agar was used for the cultivation of Legionellae. The colonies thatwere suspected to be Legionellae were transfered to sheep blood andbuffered charcoal yeast extract agar (B.C.Y.E-a-agar). The biochemicalcharacteristics were checked with cytochrom oxidase-, catalase-tests andhippuratehydrolysis. The differentiation took place by means offluorescein-iso-thiocyanat (FITC) conjugated Anti-Legionella pneumophilamonoclonal antibodies of the serogroup 1 to 11 with the directimmunfluorescent antibody technique. A Legionellae contamination was foundin 49 samples (16 %). The drains with municipal water for the boiler, thetoilets and the staff workrooms contained a germination of 101 to 103colony-forming units per 10 ml sample volumes. Neither the ozonised, withhydrocloric acid soured drinking water for the animals, nor the condensateshowed any trace of Legionellae during the period of 10 weeks in which theexperiment took place. Thirthy-seven isolated Legionellae cultures could becatagorised as Legionella pneumophila of the serogroups 1 to 11. Twelvegerm cultures were catagorised in the Nonpneumophila-group and were notdifferentiated any further.By reason of the low germ figures and the assumed resistence of the staff,the risk of illnes cause by Legionellae ispresumed to be rather small.As Legionellae were found in the samples of the laboratoryanimal house the question arose whether an antigen-contactinduced the building of antibodies in the staff as well as inthe animals. The presence of antibodies against Legionellaewas tested on 18 staff members by means of the indirect immunefluorescent technique. The purpose of the test was to provethe presence of IgG, IgM and IgA-antibodies against mixedantigens of Legionella pneumophila of the serogroup 7 to 14 anLegionella-antigen of the species L. bozemanii,L. dumophii, L. gormanii, L. longbeachae, L. micdadai andL. jordanis. One human serum contained antibodies againstserogroup 1 to 6 and 7 to 14 in the amount of 1:128 positive.These results were checked after 6 weeks, but had remainedunchanged. A pneumonia could not be diagnosed in this person,neither anamnestically nor clinically.Twenty-two rats, twenty-one pigs, twenty dogs, twenty mice,twenty-two rabbits, twenty cats and seventeen monkeys sampleswere tested at random on the presence of Legionellaeantibodies. Again the test-method was the indirectimmunfluorescence. Fluorescent marked anti-animal specificimmunglobuline to IgG were used an slides containing the mixedantigens mentioned. In the examined samples of the cats, mice,dogs and rabbits no Legionellae antibodies were found.Antibodies against L. pneumophila of the serogroup 1 to 6 and7 to 14 were discovered in a primate serum with titres of1:128 positive. Titres of 1:64 positive were found in 6 of 22rats, 4 of the 21 pigs and 5 of the 17 primate sera. 4 pigssera and 4 primate sera reacted with Non-pneumophila mixedantigens with titres of 1:64 positive.One part of the primates, pigs and rats apparently gave aserolocial response to an antigen contact by means ofLegionellae. No general conclusion is to be drawn withabsolute certainly, because only single sera were tested. Veryprobably~ we are not dealing here with fresh infections fornone of the animals showed any sign of clinical diseasesymptoms.Measures to prevent Legionellae disease for humans and animalsin Laboratory Animal Houses were suggested and discussed.