The omicron variant of COVID-19 is spreading with such astounding speed that it now accounts for an estimated 95.4% of all cases in the United States, according to new data from the Centers for Disease Control and Prevention (CDC).
That incredible figure comes from the CDC’s freshly updated Nowcast tool, which uses sequencing data to estimate the proportion of variants within communities. The tool is updated every Tuesday. The latest version includes data from the week of January 1, which is subject to change with additional updates. (Previous estimates from earlier weeks had been revised downward, for instance.) According to the tool, the once-dominant delta variant now only accounts for an estimated 4.6% of cases. This marks a significant change from just two weeks earlier when delta accounted for 61.2% of cases.
All 10 regions designated by the U.S. Department of Health and Human Services now show omicron as dominant, with the South Central and Northeast regions showing the highest proportions at 98.2% and 98%, respectively. The region that includes the lower Midwestern states of Kansas, Missouri, Nebraska, and Iowa had the lowest proportion at 77.4%.
Omicron’s rise from an unknown variant just two months ago to the dominant strain in many countries in the world is unprecedented. Although data suggests it causes a less severe form of COVID-19 than previous strains, the sheer size of caseloads means hospital systems in many areas are at risk of becoming quickly overwhelmed.
You can check out the latest update of the CDC’s Nowcast tool here.