Ann Clin Microbiol 2025;29(2):7. Evaluating the adequacy of intervals for repeat antimicrobial susceptibility testing

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Table 3. Proportion (%) of “successive” isolates with categorical change from nonresistant to resistant when the MIC change leading to this category change was >1 doubling dilution (CNRR + EMI) specified for each antibiotic a) b)
Microorganism
(no. of tested antibiotics)		AntibioticsNo. of days between isolates
1234567
A. baumannii
(n= 47,274)		Ampicillin-sulbactam2.0 (0.4, 3.5)0.3 (0.0, 0.8)0.9 (0.1, 1.8)1.6 (0.0, 3.2)2.0 (0.1, 4.0)2.2 (0.7, 3.8)1.0 (0.4, 1.5)
Ceftazidime1.7 (0.2, 3.1)0.8 (0.0, 1.7)1.3 (0.3, 2.3)1.6 (0.0, 3.2)2.0 (0.1, 4.0)2.2 (0.7, 3.8)1.4 (0.8, 2.1)
Ciprofloxacin1.7 (0.2, 3.1)0.3 (0.0, 0.8)0.6 (0.0, 1.2)1.2 (0.0, 2.6)2.0 (0.1, 4.0)1.7 (0.3, 3.0)0.8 (0.3, 1.3)
Colistin1.0 (0.0, 2.1)3.9 (1.9, 5.9)3.1 (1.6, 4.5)1.6 (0.0, 3.2)4.5 (1.6, 7.5)1.4 (0.2, 2.7)1.1 (0.5, 1.6)
Cefepime3.9 (1.7, 6.1)1.9 (0.5, 3.3)2.1 (0.9, 3.3)1.2 (0.0, 2.6)2.5 (0.3, 4.7)3.7 (1.7, 5.6)2.1 (1.3, 2.9)
Cefotaxime1.0 (0.0, 2.1)0.3 (0.0, 0.8)0.8 (0.0, 1.5)0.8 (0.0, 1.9)2.0 (0.1, 4.0)2.0 (0.5, 3.4)0.9 (0.4, 1.4)
Gentamicin2.3 (0.6, 4.0)3.2 (1.4, 5.1)3.8 (2.1, 5.4)2.0 (0.3, 3.8)5.0 (2.0, 8.1)2.0 (0.5, 3.4)2.2 (1.4, 3.1)
Imipenem1.7 (0.2, 3.1)0.3 (0.0, 0.8)1.1 (0.2, 2.0)2.0 (0.3, 3.8)2.5 (0.3, 4.7)1.4 (0.2, 2.7)1.4 (0.7, 2.0)
Levofloxacin0.8 (0.0, 1.9)0.0 (0.0, 0.0)0.9 (0.0, 1.8)1.5 (0.0, 3.1)2.2 (0.1, 4.4)2.2 (0.4, 3.9)0.8 (0.3, 1.4)
Meropenem1.6 (0.2, 3.1)0.3 (0.0, 0.8)1.3 (0.3, 2.3)2.4 (0.5, 4.3)2.5 (0.3, 4.7)1.4 (0.2, 2.7)1.4 (0.8, 2.1)
Minocycline1.0 (0.0, 2.1)1.1 (0.0, 2.1)0.8 (0.0, 1.5)3.6 (1.3, 5.9)1.0 (0.0, 2.4)1.7 (0.3, 3.0)0.9 (0.4, 1.4)
Piperacillin1.0 (0.0, 2.1)0.3 (0.0, 0.8)0.8 (0.0, 1.5)0.8 (0.0, 1.9)2.0 (0.1, 4.0)1.1 (0.0, 2.2)0.8 (0.3, 1.3)
Piperacillin-tazobactam1.3 (0.0, 2.6)0.3 (0.0, 0.8)1.1 (0.2, 2.0)1.2 (0.0, 2.6)1.5 (0.0, 3.2)1.4 (0.2, 2.7)1.2 (0.6, 1.8)
Cotrimoxazole4.3 (2.0, 6.6)4.1 (2.1, 6.1)2.5 (1.1, 3.8)5.3 (2.5, 8.1)3.6 (1.0, 6.2)5.4 (3.0, 7.7)3.0 (2.0, 3.9)
Tigecycline1.8 (0.0, 3.6)5.3 (2.6, 8.0)1.2 (0.2, 2.3)2.7 (0.4, 5.0)3.5 (0.5, 6.6)1.5 (0.0, 3.0)1.7 (0.8, 2.6)
E. coli
(n= 20,514)		Amikacin0.3 (0.0, 0.8)1.0 (0.0, 2.3)0.4 (0.0, 1.2)0.8 (0.0, 2.5)1.0 (0.0, 3.0)0.7 (0.0, 2.2)0.3 (0.0, 0.8)
Ampicillin1.3 (0.2, 2.5)1.0 (0.0, 2.3)0.8 (0.0, 2.0)0.9 (0.0, 2.5)5.1 (0.7, 9.4)0.7 (0.0, 2.2)2.0 (0.9, 3.2)
Aztreonam3.1 (1.4, 4.9)3.4 (0.9, 5.8)2.9 (0.8, 5.0)11.0 (5.3, 16.7)7.1 (2.0, 12.1)5.1 (1.4, 8.8)4.0 (2.4, 5.5)
Ceftazidime2.1 (0.7, 3.6)2.4 (0.3, 4.4)1.7 (0.0, 3.3)9.3 (4.1, 14.6)6.1 (1.4, 10.9)4.4 (0.9, 7.9)4.6 (2.9, 6.3)
Ertapenem0.3 (0.0, 0.9)0.0 (0.0, 0.0)0.0 (0.0, 0.0)2.2 (0.0, 5.3)0.0 (0.0, 0.0)0.9 (0.0, 2.6)0.4 (0.0, 1.0)
Cefepime1.2 (0.0, 2.3)1.6 (0.0, 3.4)1.9 (0.1, 3.7)10.5 (4.6, 16.4)4.4 (0.2, 8.6)2.5 (0.0, 5.3)5.0 (3.1, 6.9)
Cefoxitin0.5 (0.0, 1.3)2.4 (0.3, 4.5)3.3 (1.1, 5.6)1.7 (0.0, 4.1)5.1 (0.7, 9.4)4.4 (1.0, 7.9)3.0 (1.6, 4.3)
Cefotaxime1.8 (0.5, 3.2)2.4 (0.3, 4.4)1.7 (0.0, 3.3)6.8 (2.2, 11.4)8.2 (2.7, 13.6)5.2 (1.4, 8.9)3.2 (1.8, 4.5)
Gentamicin1.8 (0.5, 3.2)2.4 (0.3, 4.5)2.9 (0.8, 5.0)2.5 (0.0, 5.4)6.0 (1.3, 10.7)2.2 (0.0, 4.6)3.7 (2.2, 5.2)
Piperacillin-tazobactam1.1 (0.0, 2.1)0.5 (0.0, 1.5)0.9 (0.0, 2.1)6.0 (1.7, 10.4)5.5 (0.8, 10.2)2.4 (0.0, 5.1)2.0 (0.8, 3.1)
Cotrimoxazole2.1 (0.7, 3.6)2.9 (0.6, 5.1)2.5 (0.5, 4.5)5.1 (1.1, 9.1)4.0 (0.1, 7.9)2.2 (0.0, 4.7)3.5 (2.0, 4.9)
Tigecycline0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.5 (0.0, 1.4)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
E. faecalis
(n=3,705)		Ampicillin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Ciprofloxacin0.0 (0.0, 0.0)2.0 (0.0, 5.9)0.0 (0.0, 0.0)2.9 (0.0, 8.7)0.0 (0.0, 0.0)2.9 (0.0, 8.5)1.5 (0.0, 3.6)
Erythromycin3.9 (0.0, 9.3)2.2 (0.0, 6.4)6.1 (0.0, 12.9)3.1 (0.0, 9.2)0.0 (0.0, 0.0)0.0 (0.0, 0.0)2.5 (0.0, 5.3)
Linezolid0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Nitrofurantoin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Penicillin G0.0 (0.0, 0.0)0.0 (0.0, 0.0)1.9 (0.0, 5.5)2.9 (0.0, 8.5)0.0 (0.0, 0.0)0.0 (0.0, 0.0)2.9 (0.1, 5.6)
Teicoplanin0.0 (0.0, 0.0)1.9 (0.0, 5.6)1.9 (0.0, 5.6)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)1.4 (0.0, 3.4)
Tetracycline3.9 (0.0, 9.3)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)1.5 (0.0, 3.6)
Tigecycline0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Vancomycin0.0 (0.0, 0.0)1.9 (0.0, 5.7)1.9 (0.0, 5.6)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.7 (0.0, 2.1)
E. faecium
(n= 27,025)		Ampicillin0.0 (0.0, 0.0)1.0 (0.0, 2.1)1.0 (0.0, 2.0)1.1 (0.0, 2.4)0.5 (0.0, 1.6)1.6 (0.0, 3.3)1.0 (0.4, 1.6)
Ciprofloxacin0.0 (0.0, 0.0)0.4 (0.0, 1.0)0.3 (0.0, 0.8)0.4 (0.0, 1.2)0.6 (0.0, 1.8)2.2 (0.1, 4.4)0.3 (0.0, 0.6)
Erythromycin1.4 (0.0, 3.0)1.1 (0.0, 2.3)1.3 (0.2, 2.5)2.6 (0.5, 4.6)0.0 (0.0, 0.0)2.4 (0.1, 4.7)1.0 (0.3, 1.7)
Linezolid0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.1 (0.0, 0.3)
Nitrofurantoin0.5 (0.0, 1.4)2.5 (0.7, 4.3)1.6 (0.3, 2.9)3.3 (1.0, 5.6)4.3 (1.2, 7.4)2.8 (0.4, 5.2)2.0 (1.1, 2.9)
Penicillin G0.0 (0.0, 0.0)0.3 (0.0, 1.0)0.8 (0.0, 1.6)0.0 (0.0, 0.0)0.6 (0.0, 1.6)1.0 (0.0, 2.5)0.5 (0.1, 0.9)
Quinupristin-dalfopristin0.0 (0.0, 0.0)0.7 (0.0, 1.6)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.6 (0.0, 1.7)0.0 (0.0, 0.0)0.2 (0.0, 0.5)
Teicoplanin1.9 (0.1, 3.8)5.1 (2.5, 7.6)2.3 (0.7, 3.9)4.1 (1.5, 6.7)6.1 (2.4, 9.7)7.9 (3.8, 12.1)2.8 (1.7, 3.9)
Tetracycline4.1 (1.5, 6.8)3.2 (1.1, 5.3)4.0 (2.0, 6.0)4.1 (1.6, 6.7)3.1 (0.4, 5.7)5.0 (1.8, 8.2)1.8 (1.0, 2.6)
Tigecycline0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.1 (0.0, 0.3)
Vancomycin1.4 (0.0, 3.0)4.2 (1.9, 6.5)1.7 (0.3, 3.0)3.8 (1.4, 6.3)5.2 (1.9, 8.6)8.5 (4.4, 12.6)1.9 (1.1, 2.8)
K. pneumoniae
(n= 49,382)		Amikacin1.1 (0.1, 2.1)3.2 (1.6, 4.9)1.6 (0.7, 2.5)1.7 (0.2, 3.2)1.3 (0.0, 2.8)2.2 (0.7, 3.8)1.7 (0.9, 2.4)
Ampicillin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.1 (0.0, 0.3)
Ampicillin-sulbactam0.8 (0.0, 2.0)1.6 (0.0, 3.2)0.9 (0.0, 1.7)0.7 (0.0, 2.0)1.7 (0.0, 4.1)1.6 (0.0, 3.5)3.9 (1.9, 5.8)
Aztreonam2.0 (0.7, 3.3)2.5 (1.1, 4.0)3.0 (1.8, 4.3)4.2 (1.9, 6.6)3.9 (1.4, 6.4)3.9 (1.9, 6.0)3.3 (2.2, 4.4)
Ceftazidime2.0 (0.7, 3.3)3.0 (1.4, 4.6)2.6 (1.4, 3.8)4.2 (1.9, 6.5)3.9 (1.4, 6.4)4.5 (2.3, 6.7)4.2 (3.0, 5.4)
Ciprofloxacin2.4 (0.1, 4.7)4.1 (0.9, 7.3)1.5 (0.0, 3.2)2.6 (0.0, 5.5)3.3 (0.0, 7.0)1.4 (0.0, 3.2)2.6 (1.2, 3.9)
Ertapenem0.7 (0.0, 1.6)5.2 (3.0, 7.4)3.8 (2.4, 5.3)2.4 (0.5, 4.3)3.5 (0.9, 6.0)5.2 (2.8, 7.6)3.7 (2.4, 4.9)
Cefepime2.2 (0.8, 3.6)3.1 (1.4, 4.8)3.1 (1.7, 4.5)4.1 (1.7, 6.5)3.3 (0.9, 5.7)3.6 (1.6, 5.6)3.9 (2.7, 5.2)
Cefoxitin3.3 (1.7, 5.0)4.8 (2.8, 6.9)4.9 (3.3, 6.5)4.2 (1.9, 6.5)5.2 (2.3, 8.1)4.7 (2.5, 6.9)5.5 (4.1, 6.8)
Cefotaxime1.8 (0.6, 3.0)2.1 (0.7, 3.4)2.3 (1.2, 3.4)3.8 (1.6, 6.1)3.9 (1.4, 6.4)3.9 (1.9, 6.0)4.0 (2.8, 5.2)
Gentamicin3.5 (1.8, 5.2)3.5 (1.7, 5.2)3.9 (2.4, 5.3)4.5 (2.1, 6.9)3.4 (1.1, 5.8)2.2 (0.7, 3.8)4.2 (3.0, 5.4)
Imipenem1.0 (0.0, 2.3)3.5 (0.7, 6.3)3.3 (0.9, 5.7)4.0 (0.5, 7.4)1.9 (0.0, 4.4)3.0 (0.4, 5.7)4.2 (2.7, 5.8)
Levofloxacin0.7 (0.0, 1.7)1.1 (0.0, 2.2)0.6 (0.0, 1.3)0.6 (0.0, 1.8)2.2 (0.0, 4.6)2.4 (0.3, 4.5)2.8 (1.3, 4.2)
Meropenem0.7 (0.0, 1.7)3.3 (1.2, 5.4)2.7 (1.3, 4.2)1.3 (0.0, 3.1)3.7 (0.5, 6.9)3.4 (0.9, 5.9)1.1 (0.1, 2.1)
Piperacillin-tazobactam3.6 (1.8, 5.3)4.4 (2.4, 6.4)2.1 (1.0, 3.2)3.1 (1.0, 5.2)3.3 (0.9, 5.7)5.6 (3.2, 8.1)3.9 (2.7, 5.2)
Cotrimoxazole3.8 (2.0, 5.6)2.3 (0.9, 3.7)2.7 (1.5, 4.0)4.5 (2.1, 6.9)3.9 (1.4, 6.4)3.7 (1.7, 5.6)4.7 (3.4, 6.0)
Tigecycline2.9 (1.3, 4.5)5.0 (2.8, 7.1)4.3 (2.8, 5.9)4.7 (2.2, 7.3)5.2 (2.2, 8.2)3.5 (1.6, 5.5)4.3 (3.0, 5.6)
P. aeruginosa
(n=226,141)		Amikacin1.6 (1.0, 2.2)2.0 (1.5, 2.5)2.9 (2.5, 3.3)2.8 (2.1, 3.4)3.2 (2.3, 4.0)3.1 (2.3, 3.9)2.5 (1.8, 3.3)
Aztreonam4.2 (3.3, 5.2)5.4 (4.5, 6.2)6.6 (6.0, 7.2)7.2 (6.2, 8.2)8.2 (6.9, 9.5)7.1 (5.9, 8.3)9.0 (7.7, 10.3)
Ceftazidime5.9 (4.8, 7.0)5.0 (4.2, 5.8)7.0 (6.5, 7.6)7.5 (6.5, 8.4)8.4 (7.1, 9.7)9.0 (7.6, 10.3)9.0 (7.7, 10.3)
Ciprofloxacin1.6 (1.0, 2.2)1.9 (1.4, 2.4)1.8 (1.5, 2.1)2.3 (1.7, 2.8)3.0 (2.1, 3.8)3.0 (2.2, 3.9)3.7 (2.9, 4.6)
Colistin0.0 (0.0, 0.0)0.0 (0.0, 0.1)0.2 (0.1, 0.2)0.3 (0.1, 0.5)0.1 (0.0, 0.2)0.4 (0.1, 0.6)0.1 (0.0, 0.2)
Cefepime3.4 (2.5, 4.3)4.2 (3.4, 4.9)4.7 (4.2, 5.1)6.0 (5.2, 6.9)6.4 (5.2, 7.6)6.6 (5.4, 7.7)7.4 (6.2, 8.6)
Gentamicin1.2 (0.7, 1.7)1.9 (1.4, 2.4)2.0 (1.7, 2.4)2.1 (1.6, 2.7)2.9 (2.0, 3.7)3.3 (2.5, 4.2)2.8 (2.1, 3.6)
Imipenem2.5 (1.7, 3.2)3.3 (2.6, 4.0)3.9 (3.5, 4.4)4.9 (4.1, 5.8)6.3 (5.1, 7.5)5.4 (4.3, 6.4)5.9 (4.8, 7.0)
Levofloxacin1.6 (0.9, 2.3)1.7 (1.1, 2.2)1.7 (1.3, 2.1)1.9 (1.3, 2.6)3.6 (2.5, 4.7)2.6 (1.6, 3.6)3.5 (2.4, 4.6)
Meropenem2.7 (2.0, 3.5)3.3 (2.6, 4.0)4.0 (3.6, 4.5)4.7 (3.9, 5.4)6.2 (5.0, 7.3)5.1 (4.0, 6.1)6.1 (5.0, 7.3)
Piperacillin4.3 (3.3, 5.2)4.1 (3.3, 4.8)4.5 (4.0, 5.0)5.9 (5.0, 6.8)6.3 (5.1, 7.5)6.5 (5.4, 7.7)7.0 (5.8, 8.1)
Piperacillin-tazobactam4.6 (3.6, 5.7)4.3 (3.5, 5.1)5.4 (4.8, 5.9)6.4 (5.4, 7.4)8.3 (6.9, 9.7)7.8 (6.5, 9.1)7.6 (6.4, 8.9)
S. aureus
(n= 31,284)		Arbekacin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.9 (0.0, 2.6)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Ciprofloxacin0.0 (0.0, 0.0)1.8 (0.0, 3.5)3.0 (0.8, 5.2)1.6 (0.0, 3.9)6.0 (1.7, 10.4)3.8 (1.2, 6.3)2.1 (1.1, 3.1)
Clindamycin0.0 (0.0, 0.0)2.3 (0.3, 4.3)2.2 (0.3, 4.1)1.7 (0.0, 3.9)3.6 (0.1, 7.0)3.3 (0.9, 5.7)1.3 (0.5, 2.1)
Erythromycin0.0 (0.0, 0.0)2.3 (0.3, 4.3)2.2 (0.3, 4.0)1.7 (0.0, 3.9)5.3 (1.2, 9.5)3.3 (0.9, 5.7)1.5 (0.7, 2.4)
Linezolid0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Mupirocin0.5 (0.0, 1.4)0.9 (0.0, 2.1)1.7 (0.0, 3.4)2.4 (0.0, 5.2)2.6 (0.0, 5.5)0.9 (0.0, 2.2)0.5 (0.0, 1.0)
Nitrofurantoin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)1.1 (0.0, 3.2)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Oxacillin0.9 (0.0, 2.2)1.8 (0.0, 3.6)1.8 (0.0, 3.5)0.8 (0.0, 2.4)7.0 (2.3, 11.7)2.8 (0.6, 5.0)2.0 (1.0, 3.0)
Penicillin G0.0 (0.0, 0.0)0.5 (0.0, 1.3)0.4 (0.0, 1.3)0.0 (0.0, 0.0)0.9 (0.0, 2.6)0.5 (0.0, 1.4)0.6 (0.1, 1.2)
Quinupristin-dalfopristin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Rifampin0.0 (0.0, 0.0)0.9 (0.0, 2.7)1.0 (0.0, 2.8)1.7 (0.0, 5.0)0.0 (0.0, 0.0)1.0 (0.0, 3.0)1.5 (0.3, 2.7)
Cotrimoxazole0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.4 (0.0, 1.3)0.0 (0.0, 0.0)0.9 (0.0, 2.6)0.0 (0.0, 0.0)0.8 (0.2, 1.4)
Teicoplanin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)
Tetracycline0.9 (0.0, 2.2)1.3 (0.0, 2.8)3.9 (1.4, 6.4)4.1 (0.6, 7.6)4.3 (0.6, 8.0)3.3 (0.9, 5.7)1.9 (0.9, 2.8)
Tigecycline0.0 (0.0, 0.0)0.5 (0.0, 1.3)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.8 (0.2, 1.4)
Telithromycin0.5 (0.0, 1.4)1.8 (0.0, 3.5)3.1 (0.8, 5.3)1.6 (0.0, 3.9)6.0 (1.7, 10.4)4.2 (1.5, 6.9)2.4 (1.3, 3.4)
Vancomycin0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)0.0 (0.0, 0.0)

a) Each successive isolate consist of two microorganisms with the same identification from two different time points. No shade: < 3%; grey shade: 3% to 6%; dark grey shade: >6%.
b) Values represent the proportion (%) of isolates with categorical change; numbers in parentheses indicate the 95% confidence interval (CI).