Volume 29, Number 5—May 2023
CME ACTIVITY - Research
Emergence of Erythromycin-Resistant Invasive Group A Streptococcus, West Virginia, USA, 2020–2021
Lillie M. Powell, Soo Jeon Choi, Chloe E. Chipman, Megan E. Grund, P. Rocco LaSala1, and Slawomir Lukomski1
Table 1
Phenotypic antimicrobial susceptibility results in invasive group A Streptococcus isolates, by emm type and resistance determinant, West Virginia, USA, 2020–2021*
| emm type | Geno, no. | No. (%) |
|||||||||||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|
| Erythromycin |
Clindamycin |
Tetracycline |
Kanamycin |
Streptomycin |
Gentamicin |
||||||||||||||
| S | R | S | iMLSB | cMLSB | S | R | S | R | S | R | S | R | |||||||
| emm92 |
ermT, 35 |
0 |
35 (100) |
0 |
31
(89) |
4
(11) |
0 |
35 (100) |
0 |
35 (100) |
0 |
35 (100) |
35 (100) |
0 |
|||||
| emm11 |
ermA, 2 | 0 | 2 (100) | 0 | 2 (100) | 0 | 0 | 2 (100) | 0 | 2 (100) | 2 (100) | 0 | 2 (100) | 0 | |||||
| ermB, 6 |
0 |
6 (100) |
0 |
3
(50) |
3
(50) |
6 (100) |
2
(33) |
4
(67) |
0 |
6 (100) |
6 (100) |
0 |
|||||||
| emm77 |
ermA, 1 | 0 | 1 (100) | 0 | 1 (100) | 0 | 0 | 1 (100) | 0 | 1 (100) | 1 (100) | 0 | 1 (100) | 0 | |||||
| ND, 1 |
1 (100) |
0 |
1 (100) |
0 |
0 |
1 (100) |
0 |
0 |
1 (100) |
1 (100) |
0 |
1 (100) |
0 |
||||||
| emm83 |
ermA, 3 |
0 |
3 (100) |
0 |
3
(100) |
0 |
0 |
3 (100) |
0 |
3 (100) |
2
(67) |
1
(33) |
3 (100) |
0 |
|||||
| emm197 |
ermA, 1 |
0 |
1 (100) |
0 |
0 |
1
(100) |
0 |
1 (100) |
1 (100) |
0 |
1 (100) |
0 |
1 (100) |
0 |
|||||
| emm82 |
ermB, 1 |
0 |
1 (100) |
0 |
0 |
1
(100) |
0 |
1 (100) |
1 (100) |
0 |
1 (100) |
0 |
1 (100) |
0 |
|||||
| emm22 |
mefA, 1 |
0 |
1 (100) |
1 (100) |
0 |
0 |
0 |
1 (100) |
1 (100) |
0 |
1 (100) |
0 |
1 (100) |
0 |
|||||
| emm89 |
ND, 5 |
5 (100) |
0 |
5 (100) |
0 |
0 |
5 (100) |
0 |
NT |
NT |
5 (100) |
0 |
|||||||
| emm† |
ND, 10 |
10 (100) |
0 |
10 (100) |
0 |
0 |
9 (90) |
1
(10) |
2
(20) |
8
(80) |
9
(90) |
1
(10) |
10 (100) |
0 |
|||||
| Total = 66 |
16 (24) | 50 (76) | 17 (25) | 40 (61) | 9 (14) | 15 (23) | 51 (77) | 7 (11) | 54 (89) | 24 (39) | 37 (61) | 66 (100) | 0 | ||||||
*Geno, genotype; ND, resistance gene not detected; NT, not tested; R, resistant; S, susceptible. †One emm11 isolate was not inducible by D-test but showed intermediate clindamycin resistance; other emm types with no erm: emm1 (2), emm2 (1), emm12 (1), emm28 (1), emm75 (1), emm81 (3), emm87 (1).
1These senior authors contributed equally to this article.
Page created: March 06, 2023
Page updated: April 14, 2023
Page reviewed: April 14, 2023
The conclusions, findings, and opinions expressed by authors contributing to this journal do not necessarily reflect the official position of the U.S. Department of Health and Human Services, the Public Health Service, the Centers for Disease Control and Prevention, or the authors' affiliated institutions. Use of trade names is for identification only and does not imply endorsement by any of the groups named above.