Table 5.
Overall serotype distribution in multiple-serotype pneumococcal pneumonia and single-serotype pneumococcal pneumonia
| Serotypes | Number of serotypes in multiple-serotype pneumococcal pneumonia n=481 | Number of serotypes in single-serotype pneumococcal pneumonia n=276* | OR (95% CI) |
P value† | |
| PCV7 serotypes | Serotype 4, n (%) | 25 (5.2) | 7 (2.5) | 2.1 (0.87 to 5.82) | 0.079 |
| Serotype 6A/6B, n (%) | 20 (4.2) | 23 (8.3) | 0.48 (0.24 to 0.93) | 0.016 | |
| Serotype 9V/9A, n (%) | 2 (0.4) | 3 (1.1) | 0.38 (0.03 to 3.34) | 0.360 | |
| Serotype 14, n (%) | 13 (2.7) | 7 (2.5) | 1.07 (0.39 to 3.20) | 0.890 | |
| Serotype 18, n (%) | 14 (2.9) | 2 (0.7) | 4.10 (0.93 to 37.4) | 0.063 | |
| Serotype 19F, n (%) | 18 (3.7) | 18 (6.5) | 0.56 (0.27 to 1.16) | 0.083 | |
| Serotype 23F, n (%) | 3 (0.6) | 9 (3.3) | 0.19 (0.03 to 0.76) | 0.011 | |
| Additional serotypes in PCV13 | Serotype 1, n (%) | 6 (1.2) | 0 (0.0) | NA | |
| Serotype 5, n (%) | 25 (5.2) | 2 (0.7) | 7.51 (1.85 to 65.8) | 0.001 | |
| Serotype 7F/7A, n (%) | 4 (0.8) | 0 (0.0) | NA | ||
| Serotype 3, n (%) | 53 (11.0) | 44 (15.9) | 0.65 (0.42 to 1.03) | 0.051 | |
| Serotype 19A, n (%) | 29 (6.0) | 12 (4.3) | 1.41 (0.68 to 3.09) | 0.325 | |
| Non-PCV13 PPSV23 serotypes | Serotype 2, n (%) | 5 (1.0) | 0 (0.0) | NA | |
| Serotype 8, n (%) | 2 (0.4) | 0 (0.0) | NA | ||
| Serotype 9N/9L, n (%) | 22 (4.6) | 1 (0.4) | 13.2 (2.1 to 545) | 0.001 | |
| Serotype 10A, n (%) | 82 (17.0) | 22 (8.0) | 2.37 (1.42 to 4.09) | 0.001 | |
| Serotype 11, n (%) | 15 (3.1) | 21 (7.6) | 0.39 (0.18 to 0.81) | 0.005 | |
| Serotype 12/44/46, n (%) | 16 (3.3) | 1 (0.4) | 9.46 (1.45 to 398) | 0.008 | |
| Serotype 15B/15C, n (%) | 15 (3.1) | 5 (1.8) | 1.74 (0.59 to 6.20) | 0.350 | |
| Serotype 17F, n (%) | 23 (4.8) | 1 (0.4) | 13.8 (2.21 to 570) | 0.001 | |
| Serotype 20, n (%) | 2 (0.4) | 1 (0.4) | 1.15 (0.06 to 68.0) | 1.000 | |
| Serotype 22F/22A, n (%) | 17 (3.5) | 13 (4.7) | 0.74 (0.33 to 1.69) | 0.425 | |
| Serotype 33F/33A/37, n (%) | 8 (1.7) | 5 (1.8) | 0.92 (0.26 to 3.60) | 1.000 | |
| Other serotypes | Serotype 6C/6D, n (%) | 14 (2.9) | 18 (6.5) | 0.43 (0.19 to 0.93) | 0.018 |
| Serotype 23A, n (%) | 11 (2.3) | 5 (1.8) | 1.27 (0.40 to 4.71) | 0.800 | |
| Serotype 34, n (%) | 8 (1.7) | 4 (1.4) | 1.15 (0.30 to 5.27) | 1.000 | |
| Serotype 35F, n (%) | 12 (2.5) | 1 (0.4) | 7.04 (1.03 to 301) | 0.039 | |
| Serotype 35B, n (%) | 17 (3.5) | 18 (6.5) | 0.53 (0.25 to 1.10) | 0.060 |
*NT serotypes were 33 (12.0%). These samples were lytA PCR positive but could not be serotyped by our present system. It may be possible that some of these samples may contain multiple serotypes beyond the 50 serotypes that the nanofluidic PCR system could detect. As the median bacterial load of NT was almost 1 log10/mL lower than that of multiple serotypes, we considered most of NT were essentially single serotypes.
†Fisher’s exact rest was performed when the number of serotypes was ≤5 in any of the cells.
NT, non-typeable; PPSV23, 23-valent pneumococcal polysaccharide vaccine.