Thread by @kylamb8

The idea that omicron is much more mild is no longer in question. The evidence has been overwhelming showing 70-90% reduction in severe illness and mortality.

1/

https://twitter.com/kylamb8/status/1487507829753888775

A study by Kaiser Permanente in California found a 91% reduction in deaths among omicron cases vs. delta using SGTF failure as presumption of omicron.

2/

medrxiv.org/content/10.110…

Through Dec. 31, UKHSA had recorded just 75 deaths among 212,019 omicron cases (0.04% fatality rate). They have since discontinued omicron surveillance.

3/

gov.uk/government/pub…

Also using SGTF failure, severe illness in South Africa showed a 70% reduction in severe illness according to a study by the National Institute of Communicable Diseases there.

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medrxiv.org/content/10.110…

A cohort analysis studying nationwide electronic health records at Case Western found delta showed a 67% decrease in ICU admission and 84% decrease in mechanical ventilation.

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medrxiv.org/content/10.110…

In fact, if you lag the last 7 days of deaths reported to the CDC in the U.S. by 21 days to cases, the past 2 weeks have fallen from 1% to 0.37%.

Prior to these last 2 weeks, CFR using this 3-week lag had never been lower than 0.9% and was almost always between 1-3%.

6/

Here is what the rolling 7d CFR looks like in graph form

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