Watch how Covid-19 cases rose and fell across the United States
Updated 10:40 AM ET, Thu July 7, 2022
(CNN)In a few seconds, this animation shows the rise and fall of reported Covid-19 cases across the United States over an entire year.
Starting in July 2021, the rise of the Delta variant is visible first in the South, Plains, Midwest and Northeast, and then begins to fade into winter of 2021.
And then came Omicron. A dramatic rise in cases overwhelmed the map starting in December 2021 and into February 2022.
While the map's case counts fade starting in the spring of 2022, that also corresponds to a rise in the use of at-home tests, which are not automatically reported, and a period when official data reporting became less frequent.
The animation is based on county-level data collected by local governments and tracked by the Johns Hopkins University Center for Systems Science and Engineering.
You can also view and download a sharable version of this animation.
Data from Johns Hopkins University Center for Systems Science and Engineering each day starting July 1, 2021 and ending July 5, 2022. This map uses 7-day averages in an effort to smooth out reporting fluctuations, though large backlogs can cause the appearance of spikes in counties or states. New cases that are missing or not assigned to a particular county are excluded. Due to reporting anomalies, new case counts are omitted for counties in Nebraska from Sept. 25 to Oct. 1, 2021.
Correction: A previous version of the footnote misstated the year in which the animation ends.