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Table 1 HAI and NAI Titer Plus Previous Vaccination Data for the Year-4 FLUVACS Study

From: HAI and NAI titer correlates of inactivated and live attenuated influenza vaccine efficacy

    HAI Titers NAI Titers
Treatment Group No. No. w/ Day 0 and Day 30 No. w/ Day 0 and Day 30
Placebo Total 325 125 92
  Cases 30 30 29
  Controls 295 95 63
LAIV Total 814 324 227
  Cases 54 54 52
  Controls 760 270 175
IIV Total 813 279 178
  Cases 22 22 22
  Controls 791 257 156
Placebo Total 136 48 42
Restrict Cases 15 15 15
EVERVAX=1 Controls 121 33 27
LAIV Total 307 135 92
Restrict Cases 26 26 24
EVERVAX=1 Controls 281 109 68
IIV Total 288 99 58
Restrict Cases 6 6 6
EVERVAX=1 Controls 282 93 52
Placebo Total 138 54 35
Restrict Cases 11 11 10
EVERVAX=0 Controls 127 43 25
LAIV Total 388 144 105
Restrict Cases 21 21 21
EVERVAX=0 Controls 367 123 84
IIV Total 388 128 93
Restrict Cases 13 13 13
EVERVAX=0 Controls 375 115 80
  1. In the third column, all participants with an observed influenza endpoint (Cases) and all participants completing follow-up (with a post-season sample) without experiencing the influenza endpoint (Controls) are included in the counts, regardless of whether immunological data were measured. The remaining columns include the subset of these participants with HAI or NAI titer measurements at Day 0 and Day 30. For each assay HAI and NAI, all participants either had both Day 0 and Day 30 titers measured, or neither Day 0 and Day 30 titers measured. All participants with NAI titers measured also had HAI titers measured. EVERVAX is self-report of ever having received a previous flu vaccine: 1 = yes, 0 = no