*2.2. Isolation of Bacteria*

Samples were filtered using Microfil® S device (Merck, Vienna, Austria) with 0.45 μm pore filters in 4 times 250 mL portions. For each sampling, two filters were put on chromID™ ESBL Agar (bioMérieux Austria GmbH, Vienna, Austria) and two on chromID™ CARBA Agar (bioMérieux). ChromID™ agars were incubated for 24 h at 37 ◦C. Colonies were assessed and picked according to the manufacturer's manual. For pure cultures, colonies were transferred to blood agar and Endo agar (24 h, 37 ◦C) and species were finally identified with MALDI-TOF, (Vitek® MS, bioMérieux Austria GmbH, Vienna, Austria).

Thereby *Klebsiella pneumoniae* isolates could be recovered on chromID™ CARBA Agar (MurTR-KL001 on 2 February 2016; and MurTR-KL002 on 11 February 2016).
