Figure. Schematic of estimation method. An infectious person (in
red) infects a susceptible person (in green) in the same
household with probability of household secondary attack rate
(SAR1) and infects a susceptible person in a different household
with probability SAR2. The common infectious source (i.e., avian
hosts) infects a susceptible person with probability b per day.
The likelihood function is constructed from symptom-onset dates
and exposure information to estimate the above parameters The
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