Observational study suggests a third dose of the Pfizer COVID-19 vaccine can prevent severe COVID-19-related outcomes, compared with only two doses received at least 5 months before.

Effectiveness of a third dose of the BNT162b2 mRNA COVID-19 vaccine for preventing severe outcomes in Israel: an observational study – The Lancet

Invited Commentary: Boosters appear effective, but are they always needed? – The Lancet

Commentaries on Twitter

Nice analysis of boosters in @TheLancet Fri.: https://t.co/KqXInFa3a9

But I want to highlight one number:

Risk of severe disease w no booster & no coexisting conditions = 1 in 32,000 (3 per 100k).

If you have no other medical problems, this is not an urgent priority. pic.twitter.com/Qwcwsf6LIY

— David Dowdy (@davidwdowdy) October 31, 2021

Study in Israel suggests third dose of BNT162b2 mRNA vaccine effective in protecting individuals against severe COVID-19-related outcomes, compared with receiving only two doses at least 5 months before. https://t.co/g3vFqVFZLI pic.twitter.com/HfbBAPY8qP

— The Lancet (@TheLancet) October 31, 2021

Adding to the body of data for booster shot effectiveness, a new @TheLancet report of over 728,000 people w/ 3 shots vs >728,000 matched controls (2 shots):
93% reduction of Covid hospitalizationshttps://t.co/cVpANpnkHs pic.twitter.com/LlBwWi2Vtw

— Eric Topol (@EricTopol) October 30, 2021