Omicron crushed delta in the U.S. These numbers show just how fast it happened
The highly contagious coronavirus variant rose to U.S. dominance four times faster than delta
![image of virus particles floating amid a city scene](https://i0.wp.com/www.sciencenews.org/wp-content/uploads/2022/02/021022_eg_omicron-speed_feat.jpg?fit=1030%2C580&ssl=1)
First identified in South Africa and Botswana in November 2021, the omicron coronavirus variant spread rapidly. It was detected in the United States December 1 and weeks later, estimates suggest it was already the dominant variant here.
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