I've been thinking about the debate of delayed vs. immediate 2nd dose for some time

Over past week, have become convinced that getting all doses out now is better

Its NOT a no-brainer

Reasonable people can (and do!!) disagree

So here's why my thinking evolved

Thread https://twitter.com/Bob_Wachter/status/1345741327330263042

Obviously, if you want to stick to the trials (reasonable position), then stay with standard interval

But soon, we'll be confronted with question -- do we give 2nd shot to some people or 1st shot to more people

Is there clinical trial evidence that 1 dose is helpful?

Yes

2/n

Yes

There is compelling data from Pfizer and Moderna trials that after about 10 d after 1 dose, you get 80-90% efficacy

https://www.fda.gov/media/144245/download

https://www.nejm.org/doi/full/10.1056/NEJMoa2035389

So the BIG question is -- is that going to be durable beyond 21 to 28 days?

We don't know for sure

3/n

But while we may not be sure, it doesn't mean we have no idea

Here's one of our nation's most expert immunologists, @VirusesImmunity laying out her assessment of delayed vs immediate 2nd dose

https://twitter.com/VirusesImmunity/status/1345086669607890945?s=20

4/9

What I take away from Dr. Iwasaki's thread and broader experience with vaccines is that it its unlikely that a short delay will harm protection

But we can't be sure

So why take this risk at all?

Why not just stay with the clinical trial?

Reasonable question

Here's why

5/9

We are on track to have another 50K to 100K Americans die of COVID in January

And that number again in February

Most 75 year-olds won't get their first dose for many more weeks

And most 64 year-olds won't for months

And the new variant will become dominant in that time

6/9

So what @Bob_Wachter and I are arguing is not -- abandon the science

Its -- look at all the science, the whole picture

The data from the clinical trials
What we know about vaccine durability
What we know about the variant taking off

And think about what saves most lives

7/9

And to us, the answer is, get first doses out immediately

Get 2nd doses into arms as they become available later winter

Now, reasonable to make some exceptions like nursing home residents where you want to maximize protection

But if you listen to Operation Warp Speed

8/10

We will have 100M doses produced by end of January

If we can get that many into arms by mid-February, it will make a huge difference

It won't just protect many more people

If you believe that vaccines will likely slow spread, it'll slow down disease across the nation

9/10

Anyone we can protect now is someone less likely to get infected tomorrow and die in 4 weeks

Bottom line is that I realize we are pushing for something that has risk

But we should not ignore the risk of not doing this at all

Here's the op-ed again

Fin https://www.washingtonpost.com/opinions/2021/01/03/its-time-consider-delaying-second-dose-coronavirus-vaccine/