Table 2. Serotype distribution among 745 invasive pneumococcal isolates from adults (healthy vs. co-morbidities).
| Serogroups/serotypes | Healthy N = 216* | Co-morbidities N = 513* | P value |
| n° strains (%) | |||
| 1 | 55 (25) | 24 (5) | <0.001 |
| 3 | 21 (10) | 33 (6) | 0.121 |
| 4 | 11 (5) | 25 (5) | 0.901 |
| 5 | 15 (7) | 10 (2) | 0.001 |
| 6A | 5 (2) | 12 (2) | 0.984 |
| 6B | 2 (1) | 11 (2) | 0.364 |
| 6C | 1 (0.5) | 8 (2) | 0.458 |
| 7F | 27 (13) | 22 (4) | <0.001 |
| 8 | 7 (3) | 20 (4) | 0.668 |
| 9N | 0 | 11 (2) | - |
| 9V | 7 (3) | 30 (6) | 0.143 |
| 11A | 4 (2) | 14 (3) | 0.607 |
| 12 | 7 (3) | 17 (3) | 0.960 |
| 14 | 12 (6) | 37 (7) | 0.415 |
| 18C | 3 (1) | 14 (3) | 0.420 |
| 19A | 12 (6) | 37 (7) | 0.415 |
| 19F | 3 (1) | 30 (6) | 0.006 |
| 23A | 0 | 11 (2) | - |
| 23F | 2 (1) | 27 (5) | 0.006 |
| Others† | 22 (10) | 120 (23) | <0.001 |
*
A total of 745 IPD episodes. Out of 220 IPD in healthy adults, 216 (98%) were serotyped. Out of 525 IPD in patients with co-morbidities, 513 (98%) were serotyped.
†
Others [healthy (n) vs. co-morbidities (n)]: 10A (2 vs. 10), 13 (0 vs. 3), 15A (3 vs. 9), 15B (0 vs. 9), 15C (0 vs. 3), 15F (0 vs. 4), 16F (0 vs 5), 17 (0 vs. 5), 18A (0 vs. 1), 18B (0 vs. 1) 20 (0 vs. 10), 21 (0 vs. 1), 22F (5 vs. 8), 23B (2 vs. 2), 24F (2 vs. 8), 25 (2 vs. 1), 28 (0 vs. 2), 29 (0 vs. 2), 31 (0 vs. 5), 32 (0 vs. 1), 33 (3 vs. 4), 34 (0 vs. 7), 35 (1 vs. 13), 37 (0 vs. 1), 38 (0 vs. 2), 48 (0 vs. 1), non-typable (2 vs. 2).