Chime model - SIR calculation

[dzak1234]

Hello,

I am testing the following set of parameters:

Currently Hospitalized COVID-19 Patients 69 Doubling time before social distancing (days) 4 Social distancing (% reduction in social contact) 30% Hospitalization %(total infections) 2.5% ICU %(total infections) 0.75% Ventilated %(total infections) 0.5% Hospital Length of Stay 7 ICU Length of Stay 9 Vent Length of Stay 10 Hospital Market Share (%) 15% Regional Population 100,000

My t = 0 numbers are: Susceptible: 71,290 Infected: 19,653 Recovered: 9,055

Given the above initial set of inputs/parameters, I get the following parameters after application of social distancing: beta = 0.00000182445, gamma = 0.071429 (assuming 14 days for recovery). Therefore, my number of infected people during t=1 should be: I(1) = (S(0)betaI(0)-gamma*I(0)) + I(0) = (71,290 * 0.00000182445 * 19,653 - 0.071429 * 19,653) + 19,653 = 20,805

However, when I plug in the initial parameters into your CHIME model, I get infected people at t = 1 to be 20,813. I realize that the difference is small, however, the difference diverges the further out in time I go.

Any thoughts would be greatly appreciated.

Thank you.

[dzak1234]

Hello, just wanted to circle back and see if there are any thoughts regarding this. Thank you.

[ManuTel]

hi @dzak1234 I have one query that I think you can answer. Given the input, you arrive at the following SIR at t=0

My t = 0 numbers are: Susceptible: 71,290 Infected: 19,653 Recovered: 9,055

Can you please explain how CHIME estimates the t=0 numbers for infected and recovered? Thanks in Advance. I tried to do manual calculations but failed.