Thread by @DiseaseEcology

Fundamental misunderstanding of what it means for Omicron to result in less severe illness. Still no studies compare hospitalization in naive people infected w/ Omicron & Delta. All studies simply measure effect of vaccination + previous infection which we know reduce severity.

https://twitter.com/EricTopol/status/1473706952366694402

Here's best attempt to control for vaccination status & prev infection (including undetected cases). It finds 0-30% reduction in risk of hospitalization. That's tiny & much smaller than other studies that don't account for this.
imperial.ac.uk/media/imperial…
(cont)

If you read @jburnmurdoch & @EricTopol replies you'll see that they are actually trying to answer a different question. Instead of:
1) "is Omicron intrinsically milder" they are addressing 2) "Will ratio of hospitalizations/case be lower" than for Delta wave.

Answer to (1) is "unclear"; best answer I know is report above suggesting, "about the same maybe a tiny bit milder?"
Answer to (2) is: "definitely, due to higher immunity from infection + vaccination".

I took it for granted that people knew immunity reduces severe disease, including for Omicron, but @jburnmurdoch argues that that's not widely appreciated.

Lots of replies from @jburnmurdoch that I think might help some folks understand some of many complexities here. If this issue is confusing to you I'd have a read. Thanks to John for clarifying.