TABLE 2

Varicella-Related Complications According to Age Group, 1997–2008

Complication0–5 mo6–11 moRate Ratio (95% CI)bP
No. (n = 175)Rate (95% CI)aNo. (n = 343)Rate (95% CI)a
Skin superinfection634.3 (15.4–76.3)1543.7 (26.4–72.5)1.3 (0.5–3.3).308
Otitis media317.1 (5.5–53.2)1440.8 (24.2–68.9)2.4 (0.7–8.3).086
Diarrhea15.7 (0.8–40.6)926.2 (13.7–50.4)4.6 (0.6–36.2).074
Pneumonia038.7 (2.8–27.1)
Neurologicc15.7 (0.8–40.6)12.9 (0.4–20.7)0.5 (0.0–8.2).319
Miscellaneousd0617.5 (7.9–38.9)
Total1162.9 (34.8–113.5)48139.9 (105.5–185.7)2.2 (1.2–4.3).008
  • a Rate per 1000 infant varicella cases. 95% CIs are based on continuity-corrected score methods.

  • b 95% CIs for rate ratios were derived by using the δ method.

  • c Neurologic outcomes include 1 case of aseptic meningitis and 1 case of encephalitis.

  • d Miscellaneous cases include pharyngitis, asthma exacerbation, scarring, and swollen lymph nodes.