So, what does this situation look like on the ground, in a typical U.S. town? Here's a snapshot.
Here’s what the numbers look like in my region, Plymouth County in MA (yes, we have a rock!) There are 27 towns in the county, which is the seventh most populous county (out of 14) in the state. About half the cases are in one town, Brockton, which is a Boston suburb at the northern end of the county. I’m at the southern end. The remaining cases are distributed widely among the other towns; the second most cases in one town, for the towns that reported a number (a few did not), is 10 in the town of Plymouth (they have the rock), not far from the southern end.
date, number of confirmed cases, factor increase for day, absolute increase for day
3/17 5 <— schools closed
3/18 5 <— early numbers reflect lack of tests available to confirm cases
3/19 data not available
3/20 11
3/21 20
3/22 25
3/23 32
3/24 64 <— nonessential business closures go into effect statewide at noon
3/25 101 1.58 37
3/26 138 1.37 37
3/27 187 1.36 49
3/28 272 1.45 85
Here's the number of confirmed cases by day for nearby Bristol County where my wife works retail in a still-open “essential” business.
3/24 31 <— nonessential business closures go into effect statewide at noon
3/25 67 2.16 36
3/26 90 1.34 23
3/27 129 1.43 39
3/28 179 1.39 50
The vast majority of cases confirmed today (and previously) must have been contracted before the 3/24 shutdown. It won’t be until about 4/1 that we can start looking at newly confirmed cases to tell if the shutdown measures are working to reduce the local R0.
at mean 1.39 increase (last 3 days), the projection for Plymouth County is 1015 cases on 4/1
at mean 1.39 increase (last 3 days), the projection for Bristol County is 668 cases on 4/1
