At the time of writing, the coronavirus disease of 2019 remains a global health crisis of grave and uncertain magnitude. To the non-expert (such as myself), contextualizing the numbers, forecasts and epidemiological parameters described in the media and literature can be challenging. I created this calculator as an attempt to address this gap in understanding.
This calculator implements a classical infectious disease model — SEIR (Susceptible → Exposed → Infected → Removed), an idealized model of spread still used in frontlines of research e.g. [Wu, et. al, Kucharski et. al].
The dynamics of this model are characterized by a set of four ordinary differential equations that correspond to the stages of the disease’s progression.
In addition to the transmission dynamics, this model allows the use of supplemental timing information to model the death rate and healthcare burdon.
Note that one can use this calculator to measure one’s risk exposure to the disease for any given day of the epidemic: the probability of getting infected on day 218 given close contact with individuals is 0.00088% given an attack rate of 0.45% [Burke et. al].