Comparison of cases (n = 177) and healthy contacts (n = 496) in outbreaks of avian influenza H5N1 infection.

aObservations = 561, Goodness-of-fit test: P = 0.17, OR denotes odds ratio, CI denotes confidence interval. OR were adjusted for the inclusion of the three variables in the final multivariate model.bData missing for two cases and 46 healthy contacts.cData missing for 66 cases from the 59 outbreaks for which household data were not available.