TABLE 3.

MICs of drugs against 124 group A streptococci

Drug and type of straina	MIC (μg/ml)b
	Range (μg/ml)	50%	90%
CEM-101	0.008-1	0.06	0.5
Macrolide S	0.008-0.03	0.015	0.03
erm(B)	0.03-1	0.5	1
mef(A)	0.06-0.25	0.125	0.25
erm(A)	0.016-0.5	0.03	0.125
L4 mutations	0.06
Erythromycin	0.03->64	16	>64
Macrolide S	0.03-0.25	0.06	0.125
erm(B)	>64->64	>64	>64
mef(A)	8-32	16	32
erm(A)	2->64	4	>64
L4 mutations	2
Azithromycin	0.06->64	8	>64
Macrolide S	0.06-0.25	0.125	0.25
erm(B)	>64->64	>64	>64
mef(A)	0.5-16	8	8
erm(A)	2->64	16	>64
L4 mutations	2
Clarithromycin	0.015->64	4	>64
Macrolide S	0.015-0.06	0.03	0.06
erm(B)	32->64	>64	>64
mef(A)	0.5-8	4	8
erm(A)	0.25->64	2	>64
L4 mutations	1
Telithromycin	0.03-16	0.125	8
Macrolide S	0.03-0.06	0.06	0.06
erm(B)	0.03-16	8	16
mef(A)	0.125-1	0.5	1
erm(A)	0.03-0.25	0.06	0.125
L4 mutations	0.06
Amoxicillin-clavulanate	<0.015-0.125	0.03	0.03
Macrolide S	0.015-0.03	0.03	0.03
erm(B)	<0.015-0.125	<0.015	0.03
mef(A)	<0.015-0.125	0.015	0.06
erm(A)	<0.015-0.03	0.03	0.03
L4 mutations	0.03
Levofloxacin	0.5-2	0.5	1
Macrolide S	0.5-1	0.5	0.5
erm(B)	0.5-1	0.5	1
mef(A)	0.5-2	0.5	1
erm(A)	0.5-2	0.5	1
L4 mutations	0.5
Moxifloxacin	0.0125-0.5	0.25	0.25
Macrolide S	0.125-0.25	0.25	0.25
erm(B)	0.125-0.25	0.25	0.25
mef(A)	0.25-0.5	0.25	0.25
erm(A)	0.125-0.5	0.25	0.25
L4 mutations	0.25
Penicillin G	<0.008-0.125	0.015	0.015
Macrolide S	0.008-0.015	0.015	0.015
erm(B)	<0.008-0.125	0.015	0.015
mef(A)	<0.008-0.125	0.015	0.03
erm(A)	<0.008-0.015	0.015	0.015
L4 mutations	0.015
Clindamycin	0.03->64	0.125	>64
Macrolide S	0.03-0.125	0.06	0.06
erm(B)	0.06->64	>64	>64
mef(A)	0.03-0.125	0.06	0.125
erm(A)	0.06-0.5	0.125	0.25
L4 mutations	0.06

^aS, susceptible. A total of 26 macrolide-susceptible, 19 erm(B), 38 mef(A), and 40 erm(A) strains, as well as 1 strain with L4 mutations, were tested.

^b50 and 90%, MICs at which 50% and 90% of isolates, respectively, are inhibited.