Thread by @EricTopol

New data mRNA vaccine 4th dose
timesofisrael.com/israeli-trial-…
—HCW, 154 Pfizer, 120 Moderna, + control group
—Increase in antibodies > 3rd dose
—Little effect on Omicron cases
—No data yet for ? severe disease, memory B/T cells, higher or more durable protection
—Uncertain benefit/need

Last week @UKHSA published their new data on Omicron and 2 dose vs 3 dose vaccine effectiveness (VE) vs infections assets.publishing.service.gov.uk/government/upl…
In people w/o prior Covid, the booster approximately doubled VE, the 62% isn't bad (point estimate)
But

It falls off pretty fast, this vs Omicron (and Delta) symptomatic infections. So an important unresolved question is whether the 4th dose helps prevents this attrition of VE over time vs symptomatic infection and severe disease

Israel has given a 4th dose to well over 500,000 people (of 9 M population)
abcnews.go.com/International/…
Testing is aggressive (>8X US/capita) but this graph of their Omicron wave isn't encouraging vs infections with 3rd booster rate 54% (US 24%), 2-shot vaxx 64% (US 62%)

Last point, which I cannot emphasize enough:
3rd shot protection vs Omicron hospitalizations, severe disease, death is remarkably high, about as well preserved as 2 shots vs ancestral strain, and a very different look compared with VE vs infections
assets.publishing.service.gov.uk/government/upl…

Further highlighting this dichotomy in Israel
Impact of cases vs impact on severe disease/hospital or ICU admits/death
ourworldindata.org/covid-metrics-…