Table 1.

Definitions of multidrug-resistant bacteria monitored in the Zero Resistance program

Microorganism	Resistance marker
Gram-positive
Staphylococcus aureus	Methicillin (MRSA)
Enterococcus spp.	Vancomycin (VRE)
Gram-negative
Enterobacteriaceae	3rd generation cephalosporins (particularly ESBL-producing)
	Carbapenems (particularly carbapenemase-producing)
Pseudomonas aeruginosa	≥ 3 antibiotic classes, including carbapenemsa, cephalosporinsb, piperacillin-tazobactam, flouroquinolones, aminoglycosidesd and colistin
Acinetobacter baumannii	Carbapenems

^aImipenem, meropenem or doripenem; ^bceftazidime or cefepime; ^cciprofloxacin or levofloxacin; gentamicin, tobramycin or amikacin. ESBL: extended spectrum beta-lactamase; MRSA: methicillin-resistant Staphylococcus aureus; VRE: vancomycin-resistant enterococcus.