Table 2.

Factors Associated With Transmission of Influenza Virus Infection From Index Patients to Household Contacts^a

Stratum	Index Patients, No.	OR (95% CrI)	P Value
Oseltamivir therapy vs no treatment
Started at <1 d	69	0.53 (.18–1.24)	.17
Started at 1–2 d	237	0.65 (.37–1.14)	.10
Started at >2 d	161	1.15 (.59–2.18)	.67

Abbreviations: CrI, credible interval; OR, odds ratio.

^a Household contacts were stratified into 3 groups, based on the time from illness onset to medical consultation for the index patient in their household. The ORs presented here reflect the risk of infection of a household contact, comparing household contacts of index patients treated and of those not treated with oseltamivir in each stratum. The analysis was also adjusted for age and vaccination status of the household contacts and accounted for tertiary infections and infections from outside the household (see “Methods” section).