Table 2.
Mean Annual Pertussis Hospitalization and Intensive-Care Unit Admission Incidence at IMPACT According to Age Groups, 1999-2015
| Age | Hospitalization Incidence (per 100000 population [(95% CI])a | ICU Admission Incidence (per 100000 population [(95% CI])b |
|---|---|---|
| <1 year | 42.34 (32.53–52.15) | 8.64 (6.96–10.31) |
| <2 mo | 116.40 (85.32–147.49) | 33.48 (26.35–40.62) |
| 2–3 mo | 95.88 (71.56–120.20) | 14.58 (10.55–18.61) |
| 4–5 mo | 28.35 (19.49–37.22) | 2.52 (1.13–3.90) |
| 6–11 mo | 5.09 (3.42–6.77) | 0.42 (0.15–0.68) |
| 1–4 years | 0.81 (0.56–1.05) | 0.06 (0.02–0.09) |
| 5–9 years | 0.16 (0.10–0.22) | 0.005 (0–0.017) |
| 10–16 years | 0.19 (0.09–0.29) | 0.004 (0–0.012) |
| All age groups | 2.61 (2.03–3.18) | 0.50 (0.40–0.60) |
Abbreviations: CI, confidence interval; IMPACT, Canadian Immunization Monitoring Program, Active.
aThe analysis included 11 of 12 IMPACT hospitals (excluding The Hospital for Sick Children, Toronto)
bThe analysis included 10 of 12 IMPACT hospitals and their 7 respective provinces, excluding 2 hospitals from the province of Ontario (The Hospital for Sick Children and Children’s Hospital of Eastern Ontario [Ottawa]).