Omicron sweeps across nation, now 73% of new US COVID cases

AP ^ | 20 December 2021 | MIKE STOBBE

[blueplum]

NEW YORK (AP) — Omicron has raced ahead of other variants and is now the dominant version of the coronavirus in the U.S., accounting for 73% of new infections last week, federal health officials said Monday.

The Centers for Disease Control and Prevention numbers showed nearly a six-fold increase in omicron’s share of infections in only one week.

In much of the country, it’s even higher. Omicron is responsible for an estimated 90% or more of new infections in the New York area, the Southeast, the industrial Midwest and the Pacific Northwest. The national rate suggests that more than 650,000 omicron infections occurred in the U.S. last week....

...CDC’s estimates are based on thousands of coronavirus specimens collected each week through university and commercial laboratories and state and local health departments. Scientists analyze their genetic sequences to determine which versions of the COVID-19 viruses are most abundant.

On Monday, the CDC revised its estimate for omicron cases for the week that ended Dec. 11, after analyzing more samples. About 13% of the cases that week were from omicron, not the 3% previously reported. The week before, omicron accounted for just 0.4% of cases.

[lurked_for_a_decade]

https://covid.cdc.gov/covid-data-tracker/#variant-proportions

The data is being misrepresented by journalists.

The 73% number is a United States Nowcast model estimate of variants. It’s a mathematical projection and another example of fear porn! It’s a SWAG projection

Scientific Wild Ass Guess.

It is either not understood by your average layman or is being intentionally misrepresented and repeated by journalists.

Norway and Denmarks numbers are based on actual genomic testic not mathematical modelling estimates.

Nowcast definition from the CDC web page.

Nowcast is a model that estimates more recent proportions of circulating variants and enables timely public health action. CDC is providing weekly Nowcast estimates which will be updated every week on Tuesday.

Check out

https://covariants.org/per-country.

[lurked_for_a_decade]

Weighted estimates are adjusted after the fact and have historically been now where near Nowcast projections. The 73% number is fear porn. The default on the web site is to show projections. Not the hstorical weighted averages.

[jurroppi1]

I have always wondered about the sample rate and the sample size, let alone selection of which samples are sequenced - I have cautioned regarding this since I first heard about the CDC/NIH/WHO and associated testing sites/genomic sequencing labs information.

For example: (based on the info from covariants.org) in MN about 1000 tests have been sequenced in roughly the last month.

I don’t now, nor have I in the past believed that the sample size and selection were adequate to get a proper estimate or truly be statistically significant for future predictions until several months’ worth of data have been collected.

We aren’t there yet.