Table 2.

IgG-PT levels in patients with clinical pertussis versus time elapsed since disease onset

IgG-PT level (U/ml)% of patients with indicated IgG-PT level at time of serum collection after onset of diseasea
0–5 mo (n = 57)6–11 mo (n = 30)12–23 mo (n = 25)2–3 yr (n = 14)4–7 yr (n = 8)
≥10090201670
50–9911401270
20–49013283613
<20027445088
  • a n, number of patients.