Table 1.
Baseline characteristics of serotype 3 IPD cases in Massachusetts in the years 2002–2017.
| Characteristic | Serotype 3 Cases Prior to PCV 13 (n = 25) | Serotype 3 Cases Following PCV 13 (n = 18) |
|---|---|---|
| Age (month), median (range) | 26 (2–149) | 31 (0–209) |
| ≤6 | 6 (24%) | 2 (11.1%) |
| 6–≤12 | 3 (12%) | 0 (0.0%) |
| 12–≤24 | 3 (12%) | 5 (27.8%) |
| 24–≤36 | 2 (8%) | 4 22.2%) |
| >36 | 11 (44%) | 7 (38.9%) |
| Gender, Male n (%) | 14 (56%) | 11 (61%) |
| Race/ethnicity n (%) | ||
| Asian | 0 (0.0%) | 1 (5.6%) |
| African American | 1 (4.0%) | 4 (22.2%) |
| Hispanic | 7 (28.0%) | 4 (22.2%) |
| White | 11 (44.0%) | 8 (44.4%) |
| Other/Unknown | 6 (24.0%) | 1 (5.6%) |
| Immunization status with PCV 13 n (%) | ||
| Fully immunized * | 0 (0.0%) | 14 (77.8%) |
| Partially immunized + | 0 (0.0%) | 0 (0.0%) |
| No vaccination with PCV 13 | 25 (100%) | 4 (22.2%) |
| IPD syndrome n (%) | ||
| Bacteremia without a focus | 7 (28.0%) | 5 (27.7%) |
| Bacteremia with focus | 0 (0.0%) | 1 (5.6%) |
| Bacteremic pneumonia/Empyema | 14 (56.0%) | 10 (55.6%) |
| Meningitis | 3 (12%) | 2 (11.1%) |
| Osteoarthritis | 1 (4%) | 0 (0.0) |
| Mortality n (%) | 0(0.0%) | 2 (11.1%) |
| Comorbidities #n (%) | 2 (8.0%) | 3 (16.7%) |
PCV13—13-valent Pneumococcal conjugated vaccine; IPD—Invasive pneumococcal disease. * Fully immunized is defined as 2–3 doses of vaccine at 2, 4, 6 months of age and one dose after 12 months of age OR at least one dose after 24 months of age (as per CDC recommendations). + Partially immunized is defined as receipt of at least one dose of PCV 13, without being fully immunized. # Comorbidities included cerebral palsy, chronic lung disease, congenital heart disease, prematurity/low birth weight and sickle cell disease.