Skip to main content

Table 2 Numbers and proportion1 of seroconversions between study rounds for seasonal H3N2 and pandemic H1N1 among unvaccinated participants

From: Relative incidence and individual-level severity of seasonal influenza A H3N2 compared with 2009 pandemic H1N1

Subtype

Roundsa

Nominal overallb(n = 306)

2-18 (n = 31)

19-44 (n = 82)

45-64 (n = 177)

65+ (n = 16)

H1N1

1,2

29

0.09 (0.07,0.13)

10

0.32 (0.19,0.51)

7

0.09 (0.04,0.17)

5

0.03 (0.01,0.06)

0

0.00 (0.00,0.21)

2,4

68

0.22 (0.18,0.27)

11

0.35 (0.22,0.55)

18

0.22 (0.15,0.32)

35

0.20 (0.15,0.26)

2

0.12 (0.04,0.38)

H3N2

2,3

23

0.08 (0.05,0.11)

2

0.06 (0.02,0.21)

4

0.05 (0.02,0.12)

16

0.09 (0.06,0.14)

2

0.12 (0.04,0.38)

  1. aRounds of study providing the pair of samples on which seroconversion status was based
  2. bNominal overall represents the expected overall number of infections if the age distribution of the study were the same as the age distribution of Hong Kong