COVID-19 now
This map is intended to effectively communicate the current per-capita rate of COVID-19 infections for each county in the USA. The qualitative color map ranges from green (best) to violet (worst) in five bins which vary by factors of three in the per-capita cases. Color opacity is scaled by the logarithm of the confirmed 7-day cases per unit area to emphasize places with large absolute numbers of infectious cases.
Hover over a county for a popup which shows the county and state, estimated number of infectious cases per thousand people, number of confirmed cases in the county over the past seven days, the percent positive tests in the state over the past seven days, and the date at which the statistics were updated. If the updated date is more than a day ago, please refresh your browser.
Estimated actual infectious cases per capita are calculated from confirmed cases reported in the past 7 days (the New York Times) and test positivity (the COVID Tracking Project).
actual = 28 * (confirmed 7-day cases) * sqrt(7-day positive fraction)
This formula is an approximation which attempts to correct for missing cases using the approach described by Dave Blake and Peter Ellis, and assumes a person is infectious for 10 days.