|Status*||School group (n=24)||Other passengers (n=102)|
|Laboratory confirmed symptomatic case during flight||9 (38)||0|
|Suspected symptomatic case during flight||1 (4)||2 (2)|
|Immune case||2 (8)||0|
|Laboratory confirmed post-flight case†||1 (4)||2 (2)|
|Suspected post-flight case†||1 (4)||0|
|Non-case†‡||10 (42)||93 (91)|
|Unknown status||0||5 (5)|
*See methods for definitions.
†Categories that formed cohort of pandemic A/H1N1 susceptible passengers used in subsequent analysis of influenza transmission risk (n=107).
‡Comprised 86 passengers who reported no symptoms of influenza-like illness (fever or feverishness, cough, sore throat, or rhinorrhoea), seven passengers who reported symptoms but who did not meet case definition for influenza-like illness, nine passengers who met case definition but had negative nasopharyngeal swabs, and one student who was asymptomatic and had negative serology but was positive for pandemic A/H1N1 on nasopharyngeal swab.