Thread by @celinegounder

1/ Data out today on single-dose & two-doses of J&J COVID vaccine.

Good news for those ~15M Americans who went with J&J.

Real-world evidence on effectiveness of single-dose J&J:
~80% vs *any* diagnosis of COVID
~80% vs hospitalization
Stable over time

medrxiv.org/content/10.110…

2/ In states with a high incidence of the Delta variant, vaccine effectiveness in June/July 2021:
~80% vs *any* diagnosis of COVID
~85% vs hospitalization from COVID

medrxiv.org/content/10.110…

3/ Not surprisingly, vaccine effectiveness vs *any* diagnosis of COVID was
- higher in people under 50 (83%)
- lower in immunocompromised (64%)

medrxiv.org/content/10.110…

4/ A single dose of the J&J vaccine works really well at preventing hospitalization (& death).

~80-85% protection against hospitalization is only slightly lower than what we're seeing with 2 doses of the mRNA vaccines (~85-90%)
fda.gov/media/152241/d…

5/ 2nd dose of J&J vaccine given 56 days after 1st dose yielded:
100% protection vs severe COVID
75% protection vs symptomatic COVID worldwide
94% protection vs symptomatic COVID in the U.S.

**note: median follow up was only 36 days after 2nd dose**

6/ J&J COVID vaxx is an important tool for vaccinating people in the US & globally.

1 shot = great

2 shots = excellent

But we need to continue following vaccine effectiveness, esp vs hospitalization/death, over time (as with mRNA vaccines) to confirm no waning of protection.