On Tuesday, the CDC updated the Variant Proportions tab of its COVID-19 data dashboard. This update included some alarming information: Omicron had jumped from causing about 0.4% of cases in the week ending December 4, to 2.9% of cases in the week ending December 11. In the New York and New Jersey area, it was causing 13% of cases.
At this rate of increase, we can anticipate that, as of yesterday (December 18), Omicron is already causing roughly 21% of cases in the U.S.—and more than 90% of cases in New York and New Jersey. But because of the CDC’s delayed updates, the majority of people who go look at the CDC’s dashboard anytime before its next update, this coming Tuesday, would likely presume that Omicron is still causing a tiny minority of cases.
I’ve written before about the delays in collecting and reporting coronavirus sequencing data. It can take weeks for a COVID-19 test sample to go from a patient’s nose to a nationwide sequencing database, which leads to inevitable lags in the U.S.’s genomic surveillance. This is understandable. But in a crisis moment, when Omicron is here and spreading rapidly, the agency should clearly label the lags and update its projections to provide a more accurate view of the variant’s growth.
What’s more, the CDC’s data update on Tuesday was not communicated widely; Director Dr. Rochelle Walensky gave a TODAY Show interview, and that was about it.
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