Thread by @VincentRK

Reminder: You cannot compare seriousness of Omicron with delta or wild strain by comparing crude rates of hospitalization or deaths

Omicron faces a different, more immune population: half the world is vaccinated and/or had Covid. Millions of vulnerable have died due to COVID.
1/

Vaccination rates are very high in age >65 population. So the most susceptible now are younger & more fit. So Omicron even if intrinsically more serious will appear milder.

Even age adjusted comparisons won't account for pre-existing immunity from prior Covid or vaccination.
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Even if omicron causes less serious disease, the high transmissibility is itself a concern because:

a) more rapid spread will cause more people to be affected in a short period of time: A smaller % of a larger number getting very ill will take up hospital & ICU beds
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b) Where I live, one of the most medically advanced states in the US, Minnesota, there was a story out that there are no ICU beds. Hospitals are full. Means people with all other conditions will get suboptimal care.
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So unless omicron is like common cold (unlikely) or 95% of the public are fully vaccinated like against measles (we are at 60%), we still have a lot of people vulnerable

Young getting ill doesn't affect only the young when dealing with a highly transmissible respiratory virus
5/

So it's wise to take omicron seriously and try to get vaccinated, boosted, follow masks and precautionary measures till we learn more.

Simultaneously vaccine makers and governments need to do everything possible to get the rest of the world vaccinated. Else this cycle repeats.

This excellent thread from @ASlavitt explains how even if omicron was intrinsically not more transmissible it can still spread faster because the mitigating effect of preexisting immunity can be less on omicron than it was against delta— omicron has all those extra mutations

https://twitter.com/aslavitt/status/1468767014881677315