Fig. 1.

Proportions of household members meeting case criteria (using a composite definition based on symptoms and RT-PCR results) in different intervention groups and for different delay intervals between the time of symptom onset of index case and recruitment into the study. The 95% confidence intervals (CI) are represented by vertical bars. To aid direct comparison with previous work (7), these estimates excluded the 63 households in which the index patient did not have RT-PCR-confirmed infection or a household contact had RT-PCR-confirmed infection at the initial household visit.