TABLE 2.

Distribution of macrolide resistance phenotypes, genotypes, and MIC ranges for erythromycin, clindamycin, and azithromycin among invasive and noninvasive S. pneumoniae isolates

Phenotype	Genotype	MIC range (μg/ml)			No. of isolates
		Erythromycin	Clindamycin	Azithromycin	Total	Invasive	Noninvasive
M type	mef(A)	1-48	0.016-0.19	1-256	36	24	12
MLSBa	erm(B)	48->256	>256	>256	23	9	14
MLSBb	A2058G in 23S rRNA gene	>256	2	>256	1		1
Total					60	33	27

^aIncluding one inducible strain (iMLS_B).

^bOne weak cMLS_B strain (strain 01-41).