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[stem-dev] Operon Ebola Models Available

I updated the STEM Wiki documentation and uploaded the Operon "B2" Ebola model project for the United States. I will upload the West Africa project as well shortly. My model predicts a 'time to peak infected' of 375 days post-introduction into the U.S.

My results agree VERY CLOSELY with the observed multi-country outbreak doubling time. (14.79 days in model, vs 15.74 days in reality).

The latest Operon Labs 'B2' Ebola Outbreak Model SEIR parameters are as follows (derived from the NEJM/WHO data):

1/σ (Incubation Period) : 11.4 days (Multi-day Exposures, All Countries, Observed)

1/γ (Infectivity Period): 16.4 days (Interval from Symptom onset to Hospital Discharge, All Countries)

σ (Incubation Rate/Day)  : 1 / 11.4 days = 0.08771930

γ (Infectivity Rate/Day)  : 1 / 16.4 days = 0.06097561

δ (Fatality Rate/Day) : 3 * γ = 0.1829268 (Try for ~71% Case Fatality Rate)

R0 (Reproduction Num#) : 1.84 ( Weighted Avg, All Countries)

βstem(Transmission Rate) = R0 * (γ + δ)

βstem(Transmission Rate) = 1.84 * (γ + δ)

βstem(Transmission Rate): = 0.4487805

Experimental testing of the above parameters in the United States with standard SEIR+D resulted in the following results:

Td_model (Model Doubling Time) = 14.79 days

Td_actual (Actual Doubling Time) = 15.74 days (Weighted Average, Liberia+SL+Guinea)

Serial Interval (Model Serial Interval) = 19.6 days

Serial Interval (Actual Serial Interval) = 17.6 days

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