The SIR Model

The SIR model is a system of ordinary differential equations with two main parameters: the infection rate b and the recovery rate k. Using the chart below, play around with values of b and k to see what helps flatten the curve.

b: infection rate



k: recovery rate

Key Statistics

People Infected in 1 year

Max infected on 1 day

What does this mean?

You can play around with the graph for as long as you like, but one thing will become abundantly clear before long: we have to lower b. The only way to keep the red line under the capacity of our healthcare system is to lower the infection rate, by washing your hands and following appropriate social distancing measures. It is clear that our healthcare system simply does not have a huge capacity, so it's imperative that we lower b so it gets as close to k as possible. Who says math can't save lives?

The Infection Curve

Below is the graph of only the infection curve. It's pretty clear to see that reducing the max infected people
below the capacity of the healthcare system is going to be very difficult.

b: infection rate



k: recovery rate

Key Statistics

~924,000

Hospital Beds in the USA

Max infected on 1 day


Max seriously infected on 1 day