Table 2.
Streptococcus pneumoniae Colonization and Associated Antibacterial Resistance During the First Year of Life, Stratified by Antibiotic Exposure During the Previous 4 Months
| Pneumococcal Isolates | Nursery | 4 Months | 8 Months | 12 Months | ||||
|---|---|---|---|---|---|---|---|---|
| Infant Antibiotica | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic |
| Nb | 2 | 324 | 20 | 189 | 25 | 132 | 30 | 114 |
| Pneumococcus | 0 | 1 | 0 | 15 | 0 | 7 | 3 | 12 |
| Serotypes (N = 1 unless specified) | NA | 38 | … | 11A, 15A, 15C (3) 16F, 22F, 23A, 23B, 35B (3), 9N (2), NT | NA | 11A, 15B (2), 22F, 23B(2), 33 | 7C, 9N, 11A | 6A PCV13, 15A, 15C, 23A, 23B(4), 35B(2), 7C, NT |
| AMRc | 0 | 1 | 0 | 7 | 0 | 3 | 0 | 5 |
| PCRc | 0 | 1 | 0 | 3 | 0 | 1 | 0 | 2 |
| MDR1c | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 2 |
| MDR2c | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
| Infant or household antibiotica,d | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic | Antibiotic | No Antibiotic |
| N | 193 | 133 | 48 | 161 | 35 | 122 | 37 | 107 |
| Pneumococcus | 0 | 1 | 1 | 14 | 1 | 6 | 4 | 11 |
| AMRc | 0 | 1 | 0 | 7 | 0 | 3 | 1 | 4 |
| PCRc | 0 | 1 | 0 | 3 | 0 | 1 | 0 | 2 |
| MDR1c | 0 | 0 | 0 | 3 | 0 | 0 | 0 | 2 |
| MDR2c | 0 | 0 | 0 | 0 | 0 | 0 | 0 | 0 |
Abbreviations: AMR, any antimicrobial drug resistance; MDR1, resistance to beta-lactam plus at least 1 additional drug class; MDR2, resistance to at least 3 drug classes; NA, not applicable; PCR, penicillin resistance; PCV13, pneumococcal conjugate vaccine 13-valent strain (1,3,4,5,6A, 6B, 7F, 9V, 14, 18C, 19A, 19F, 23F).
aSince previous visit or within previous 4 months if visit was missed or delayed.
bNot including infants or household with missing antibiotic exposure data.
cIntermediate or resistant.
dIncluding maternal antibiotics received during delivery.