Thread by @Bob_Wachter

1/ Covid (@UCSF) Chronicles, Day 66

The flow through the Covid information firehose isn’t getting any lighter, with extraordinary amounts of new data and insights each day. So here's a Potpourri Friday – the stuff that I found most interesting this week. There’s plenty…

2/ First local data. @UCSFHospitals, 12 cases, 4 on vents. 2% of Covid tests pos; rock stable. SF: 2320 cases. A large spike today (Fig L), but looks like a data dump after a lag this week. 3 new deaths (now 40), bit worrisome & bears watching. But hospitalizations down (Fig R).

3/ Now the news, starting with vaccines. We’ve discussed the @moderna_tx study bit.ly/2XqpCdj. Now a new @TheLancet vaccine trial bit.ly/2Xl8ghV, with similar results in different vaccine type – & this one in a peer-reviewed journal (vs Moderna’s press release).

4/ So we have 2 studies in 1 week testing different vaccines – both were safe & induced neutralizing antibodies in many pts. And, in another study bit.ly/2Xfs2eo, monkeys who recovered from Covid were protected against reinfection – more support that antibodies=immunity.

5/ Do we need 2 vaccines? There’s precedent: the polio vaccine we use in the U.S. is the injectable Salk vaccine, whereas the oral Sabin vaccine is used in some developing countries (a bit less safe but easier to administer & cheaper) bit.ly/3cXmfB5. Both work.

6/ Other reasons for >1 Covid vaccine: 1) need billions of doses, so useful to have >1 company producing them; 2) @moderna_tx is based in U.S.; other vaccine is from China. Wouldn't surprise if nations reserve vaccines for their own citizens before making them widely available.

7/ Interesting @NewYorker piece bit.ly/2XkAo4x gives inside story of @moderna_tx's race for a vaccine. Remember Fauci’s "12-18 month" estimate for a vaccine timeline – this was predicated on favorable results right about now, so it’s nice to see that we’re on track.

8/ Why so long? Longest lag will be testing in large populations & waiting (cue worldwide toe-tapping) to see if vaccine works. Then we're at the mercy of the virus – if this was NYC in March, it wouldn’t take too long to tell. But if in SF (with few cases), it would take a while

9/ A challenge trial – yes, blowing SARS-CoV-2 up someone's nose – would be faster & cheaper. @tradeoffspod discusses ethics of challenge trials bit.ly/2LOULl6 Bottom line: ethically tricky, but if it shortened pipeline by 3 months, it could save many thousands of lives.

10/ Potential problem: likely recruits would be healthy young'uns (low risk of bad outcomes if vaccine didn’t work), but that might not accurately predict whether the vaccine works in 75-year-olds in nursing homes. Some older (& sick) people don't respond as well to vaccines.

11/ And the billion dollar question: would it be ethical to pay “volunteers”? Sorting these challenge test issues out could be Ethicist Full Employment Act. And we do need to sort it out now, so that we're ready to roll if a candidate vaccine is poised to test for efficacy.

12/ Since we’re all desperate to get our lives back, it’s easy to embrace optimistic view & overlook some real challenges. In @FT, a sober analysis of the challenges of getting to the vaccine finish line on.ft.com/2ZxZwHN Bottom line: an effective vaccine isn't a slam dunk.

13/ Other news that caught my eye this week:

New @TheLancet study puts a nail in hydroxychloroquine's coffin wapo.st/36m53m6 It's observational, but strong methods bit.ly/3cWcMKf It's time to leave HCQ to our rheumatology patients (and Trump, if he wants).

14/ @CDCgov toned down its warning re: risk of catching Covid from touching surfaces wapo.st/2LOXiM8 They cite no new studies. Sadly, given the politicization of the CDC, I've lost some trust & this won’t change anything I do (still clean hands lots & wipe surfaces).

15/ Last week, I discussed my biggest Covid surprises bit.ly/3d2AYe8. Add to the list the phenomenon of super-spreaders – while average Covid pt infects ~2.5 others, it’s wildly heterogeneous, w/ some pts infecting dozens & others infecting no one bit.ly/3cXP7Jg

16/ That doesn’t give us any practical guidance (since we have no way of knowing who is a super-spreader), but studying super-spreaders might offer important insights into the virus or the host, insights that could aid in finding new treatments or approaches.

17/ Many papers on opening up, incl. Zeke Emanuel et al @TheAtlantic on camps bit.ly/3e8WVIq They argue (& I agree) that camp should be on: low risk, & keeping kids home all summer has risks too. As w/ other openings, must mitigate risk & be ready to abort if new cases.

18/ And @BrookingsInst analysis brook.gs/2TqLAeX highlights trend that could sway presidential race – Covid has cooled on the coasts, but it's picking up speed in middle America, esp. in counties that voted Trump. Hope they're ok, but if they flare that’ll be tough to spin

19/ This is fun: @ucsf Medical Grand Rounds (yesterday: bit.ly/2zmFplf), previously a sleepy affair attended by ~40 MDs, is now covered like a sporting match in our charming local paper, @MLNow bit.ly/2XplZUC I’m particularly fond of the opening graphic, below.

20/ Will sign off for the long weekend. My plans: socially distanced golf, seeing friends (n=2) for a dinner outside, and – gasp – a haircut at home. Hopefully will turn out better than Newman's. Wish me luck!

Stay safe, be kind. I'll be back Tuesday.