[Occurrence of antibiotic-resistant klebsiellas in waste water]

The investigated oxidation pond treatment plant reduces the Klebsiellae content in average from 2.5 X 10(4)/ml in raw waste water to less than 10/ml in effluent. Most frequently K. pneumoniae was isolated (92.8%). From the raw waste water multiple resistant Klebsiellae were isolated continuously, including gentamicin and trimethoprim resistant strains which transfer their antibiotic resistance in 74.4% of all cases to E. coli K-12. In sterile raw waste water transfer frequencies were found ranging from 10(5) to 10(-7). In Klebsiella wild strains frequently several plasmids could be detected.