|-
!style="width:150px"|
!style="width:200px"|Pre-exposure PRN <br>216-874!style="width:200px"|Pre-exposure PRN <br>≥1052
|-
!Post-exposure PRN<br>boosted†
|-
!style="width:150px"|
!style="width:200px"|Pre-exposure PRN <br><1052!style="width:200px"|Pre-exposure PRN <br>≥1052
|-
!Non-cases with<br>≥1 symptom‡
::‡suggestive of subclinical infection
::χ<sup>2</sup> test ''p''<0.002
{|class="wikitable" style="margin-left:40px; text-align:center"
|+Comparison between Cases and Non-cases; serologically confirmed
|-
!style="width:150px"|
!style="width:133px"|Pre-exposure PRN<br>≤120
!style="width:133px"|Pre-exposure PRN<br>121-1051
!style="width:133px"|Pre-exposure PRN<br>≥1052
|-
!Cases with<br>no vaccine
|1 unvaccinated case
|
|
|-
!Cases with<br>1 vaccine
|7 unvaccinated case
|
|
|-
!Non-cases with<br>no vaccine
|
|0 unvaccinated non-case
|0 unvaccinated non-case
|-
!Non-cases with<br>1 vaccine
|
|36 vaccinated non-cases
|35 vaccinated non-cases
|}