The COVID-19 Invasion of the U.S.

RUN! - Cycle through daily maps from March 15 through yesterday. Halt to stop run. (Spacebar also stops and starts display.)
ZOOM - Switch to "zoom" mode (works when either running or halted). Left click to zoom in, right click to zoom out. Press and hold to move around on zoomed map.
< or > - Stop if running, reverse direction when resuming (i.e., can run backwards.). When halted single step through dates. (May also use right and left keyboard arrows).
Example: To review changes for past week click halt or press LEFT arrow key while on last date to stop run and go back one day. Click LEFT arrow six additional times to go back one week. Use right arrow key to step forward through previous week.
NOTE:This display is a series of daily snapshots showing the spread of the epidemic in the U.S. from 15 March to the present. The colors of the counties are based on an arbitrary "hotspot score" which takes account of the per capita infection rate and the recent growth rate in that county. per capita infection rate and the recent growth rate in that county.