Heat map of the percentage of E. coli derivatives with acquired resistance to particular antibiotics. I – Fluoroquinolones, II – Penicillins, III – Cephalosporins, IV – Carbapenems, V – Aminoglycosides, VI – Others, CIP – ciprofloxacin, NOR – norfloxacin, OFX – ofloxacin, AML – amoxicillin, AMC – amoxicillin/clavulanate, PRL – piperacillin, CAZ – ceftazidime, FOX – cefoxitin, CTX – cefotaxime, IMI – imipenem, GN – gentamycin, TN – tobramycin, AK – amikacin, NET – netilmicin, NI – nitrofurantoin, W – trimethoprim, SXT – trimethoprim/sulfamethoxazole, NT – not tested, Avg – average of percentage of E. coli derivatives with acquired resistance to all antibiotics.