From: Pertussis hospitalizations among term and preterm infants: clinical course and vaccine effectiveness
 | Term infants | Preterm infants | ||||
---|---|---|---|---|---|---|
Age in months↓ | Vaccinated at admission % (n) | Coverage in general population | Vaccine effectiveness (95% CI)a | Vaccinated at admission % (n) | Coverage in general population | Vaccine effectiveness (95% CI)a |
Main analysis | ||||||
 0 m | 0% (0/1) | na | na | 0% (0/1) | na | na |
 1 m | 1.4% (2/144) | 1.9% | na | 0% (0/14) | 1.3% | na |
 2 m | 34.2% (52/152) | 90.9% | 95%b (93–96%) | 60% (9/15) | 84.9% | 73%b (20–91%) |
 3 m | 85.9% (67/78) | 98.8% | 93% (85–96%) | 86.7% (13/15) | 97.9% | 86% (9–96%) |
 4 m | 93.8% (30/32) | 99.4% | 91% | 100% (4/4) | 99.4% | na |
Sensitivity analysis | ||||||
 0 m | 0% (0/1) | na | na | 0% (0/1) | na | na |
 1 m | 0.9% (1/115) | 1.9% | na | 0% (0/14) | 1.3% | na |
 2 m | 33.7% (33/98) | 90.9% | 95%b (92–97%) | 60% (9/15) | 84.9% | 73%b (20–91%) |
 3 m | 89.4% (42/47) | 98.8% | 90% (71–96%) | 86.7% (13/15) | 97.9% | 86% (9–96%) |
 4 m | 100% (14/14) | 99.4% | na | 100% (4/4) | 99.4% | na |