TABLE 2.

Serotypes and antibiotic MICs of 13 S. agalactiae strains with the M phenotype of macrolide resistance isolated from vaginorectally colonized pregnant women

Isolate	Strain no.	Isolation date (mo/day/yr)	Serotype	mef gene	MIC (μg/ml) of antibiotica
					Pen	Amp	Ery	Azi	Cli	Tet	Rif	Chl	Sxt	Cip	Lev
1	B223605	2/07/2003	1a	mef(E)	<0.03	<0.25	4	4	<0.25	>4	<1	<4	<0.5/9.5	1	1
2	B220857	6/05/2003	1b	mef(E)	<0.03	<0.25	4	4	<0.25	>4	<1	<4	<0.5/9.5	1	1
3	B221331	7/17/2003	1b	mef(E)	<0.03	<0.25	8	4	<0.25	>4	<1	<4	<0.5/9.5	1	1
4	B222561	11/20/2003	1b	mef(E)	<0.03	<0.25	4	4	<0.25	>4	<1	<4	<0.5/9.5	1	1
5	B222696	12/04/2003	1a	mef(A)	<0.03	<0.25	4	4	<0.25	>4	<1	<4	<0.5/9.5	2	2
6	B220756	6/24/2004	III	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	>8	<0.5/9.5	1	1
7	B220783	6/28/2004	1b	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	<4	<0.5/9.5	2	1
8	B220815	6/30/2004	III	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	<4	<0.5/9.5	1	1
9	B220840	7/04/2004	IV	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	<4	<0.5/9.5	1	1
10	B220867	7/06/2004	III	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	<2	<0.5/9.5	1	1
11	B221495	9/03/2004	II	mef(E)	0.06	<0.25	8	4	<0.25	>4	<1	<2	<0.5/9.5	1	1
12	B222129	11/04/2004	V	mef(E)	<0.03	<0.25	4	>4	<0.25	>4	<1	<2	<0.5/9.5	1	1
13	B222261	11/18/2004	1b	mef(E)	<0.03	<0.25	8	>4	<0.25	>4	<1	<2	<0.5/9.5	<0.5	<0.5

^aPen, penicillin; Amp, ampicillin; Ery, erythromycin; Azi, azithromycin; Cli, clindamycin; Tet, tetracycline; Rif, rifampin; Chl, chloramphenicol; Sxt, trimethoprim-sulfamethoxazole; Cip, ciprofloxacin; Lev, levofloxacin.