Ann Clin Microbiol 2025;28(2):1. Isolation frequency and antimicrobial susceptibilities of Bacillus species in a tertiary care hospital in Korea in the past four years (2020–2024): a retrospective surveillance study
| Bacillus speciesb | VAN (266)a | PEN (266) | TET (266) | CLI (266) | ERY (266) | SXT (266) | CIP (266) | GEN (266) | RIF (266) | IMP (231) | AMP (231) | LEV (231) |
|---|---|---|---|---|---|---|---|---|---|---|---|---|
| B. amyloliquefaciens (2/2) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. amyloliquefaciens ssp. plantarum (11/9) | 0 | 9.1 | 9.1 | 9.1 | 0 | 18.2 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. asahii (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. cereus (46/36) | 0 | 93.5 | 4.3 | 0 | 0 | 17.4 | 4.3 | 0 | 0 | 2.8 | 91.7 | 2.8 |
| B. circulans (11/7) | 9.1 | 27.3 | 9.1 | 81.8 | 27.3 | 18.2 | 9.1 | 9.1 | 0 | 0 | 0 | 0 |
| B. clausii (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. cytotoxicus (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. flexus (1/0) | 0 | 0 | 0 | 0 | 100 | 0 | 0 | 0 | 0 | – | – | – |
| B. gibsonii (2/2) | 0 | 0 | 0 | 50.0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. halosaccharovorans (1/0) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | – | – | – |
| B. idriensis (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. infantis (4/4) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. licheniformis (21/19) | 0 | 71.4 | 0 | 71.4 | 28.6 | 0 | 0 | 0 | 0 | 0 | 73.7 | 0 |
| B. mojavensis (3/2) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. oceanisediminis (1/1) | 0 | 100 | 0 | 100 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. pumilus (14/13) | 0 | 0 | 7.1 | 64.3 | 7.1 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. simplex (7/7) | 0 | 28.6 | 0 | 0 | 14.3 | 0 | 0 | 0 | 0 | 0 | 28.6 | 0 |
| B. sonorensis (8/7) | 0 | 75.0 | 0 | 25.0 | 12.5 | 0 | 0 | 0 | 0 | 0 | 14.3 | 0 |
| B. subtilis (21/16) | 0 | 4.8 | 0 | 28.6 | 0 | 0 | 0 | 0 | 4.8 | 0 | 6.3 | 0 |
| B. thuringiensis (9/8) | 0 | 100 | 0 | 0 | 11.1 | 33.3 | 11.1 | 0 | 0 | 0 | 100 | 0 |
| B. vallismortis (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| B. velezensis (1/1) | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Bacillus species (98/92) | 0 | 72.4 | 1.0 | 40.8 | 10.2 | 2.0 | 1.0 | 0 | 2.0 | 0 | 67.4 | 1.1 |
| Total | 0.4 | 57.1 | 2.3 | 31.6 | 9.0 | 6.4 | 1.9 | 0.4 | 1.1 | 0.4 | 52.4 | 0.9 |
Values are presented as %.
aNumber in parenthesis refers to the tested number of isolates.
bThe number before the slash in parentheses is the number of 266 strains tested against nine antimicrobial agents excluding imipenem, ampicillin, and levofloxacin, and the number after the slash in parentheses is the number of strains tested against all 12 antimicrobial agents.
Abbreviations: VAN, vancomycin; PEN, penicillin G; TET, tetracycline; CLI, clindamycin; ERY, erythromycin; SXT, cotrimoxazole; CIP, ciprofloxacin; GEN, gentamicin; RIF, rifampicin; IMP, imipenem; AMP, ampicillin; LEV, levofloxacin.