Bob Wachter Profile picture
Jul 15, 2021 4 tweets 2 min read Twitter logo Read on Twitter
If you're wondering how bad Delta really is, even in highly vaccinated SF (76% of >age 12 fully vaxxed) & still w/ a lot of masking (most folks in stores), we're seeing a pretty steep Covid uptick. Daily cases up 4-fold (10->42; Fig L), hospital pts doubled (9->19; R)(Thread 1/4) ImageImage
Uptick mirrored @UCSFHospitals: Covid inpatients (we were at ~3 pts two-wks ago) now 13 (Fig L). Overall test positivity rate was well below 1%; it's now up to 2.6% (Fig R). Even more worrisome, test positivity rate in asymptomatic pts was ~0.15%, now up 6-fold to 0.9%. (2/4) ImageImage
I don't have vaccinated/unvaxxed breakdown for SF & UCSF – I assume most severe cases are in unvaxxed. But even for vaxxed, w/ more Covid in air expect more breakthru cases. As for me, I'm back to double-mask in stores. Still indoor dining but might abort if trends continue.(3/4)
The SF # s are still fairly low, & are cause for caution, not panic. But this kind of uptick in SF (U.S.'s vaccination leader) shows that Delta is very real – the places w/ much lower vax rates may well get clobbered. Alas, doesn't seem like there are many persuadables left.(4/4)

• • •

Missing some Tweet in this thread? You can try to force a refresh

Keep Current with Bob Wachter

Bob Wachter Profile picture

Stay in touch and get notified when new unrolls are available from this author!

Read all threads

This Thread may be Removed Anytime!


Twitter may remove this content at anytime! Save it as PDF for later use!

Try unrolling a thread yourself!

how to unroll video
  1. Follow @ThreadReaderApp to mention us!

  2. From a Twitter thread mention us with a keyword "unroll"
@threadreaderapp unroll

Practice here first or read more on our help page!

More from @Bob_Wachter

Aug 18
Covid (@UCSF) Chronicles, Day 1249
While good data are far harder to come by than in the past, it’s clear that we’re experiencing another Covid uptick. Today: what that means and how you might choose to alter your behavior in response. (1/25)
First, the evidence for the uptick (I don’t say “surge” since I associate that with the massive surges of the past):
This curve of hospitalizations (a reasonable proxy for the amount of Covid in the community) shows a definite, but relatively mild, upward trend. (2/25) Image
Alas, one can't look at any single measure to quantify an uptick anymore. But all arrows now point in the same direction: up (⬆ wastewater,⬆ hospitalizations,⬆ deaths,⬆test positivity). Even my fave measure, @UCSFHospitals’ asymptomatic test positivity rate, is no… (3/25)
Read 25 tweets
Jul 13
Until this week, I remained a NoVid, which I chalked up to being fairly cautious, fully vaxxed & a bit lucky.
This week my luck ran out. My case is a cautionary tale, particularly for the “just a cold” folks. Mine definitely was not...I literally have scars to show for it. (1/22)
I’ve got my 2nd bivalent in April, so my protection against a severe case was still strong, but the 2-3 month window of protection vs. getting Covid had passed. I've let down my guard a bit: still masking on planes & in crowded rooms, but I do now eat and drink indoors. (2/22)
This week, I was on clinical duty @UCSFHospitals. We are still required to mask in patient areas (good!). I felt fine until Sunday afternoon when, after leaving the hospital, I noticed a dry cough. By Sunday night, I felt flu-ish, with a sore throat, fever, and chills. (3/22)
Read 22 tweets
May 23
Covid (@UCSF) Chronicles, Day 1161
With the Pub Health Emergency over, it's a good time to update you on my view of Covid & my current approach to Covid behavior – which is now based on 2 principles:
1) Is the risk worth it?
2) Can I live w/ the behavior for the long haul? (1/25)
First, let’s review today's situation. Since Omicron's emergence in 11/21, the biggest surprise has been the absence of surprises. Yes, we’ve seen a few variants that led to mild surges, but we haven’t had to interrogate our Greek dictionary for a new letter for 18 months. (2/25)
mRNAs still work great in preventing severe infection, and Paxlovid, home tests, & ventilation still work well too. Long Covid remains a concern, but we know that both vax & Pax lower its frequency, that most (though definitely not all) folks… (3/25)…
Read 25 tweets
Feb 17
Important @TheLancet systematic review finds Covid infection confers robust & long-lasting (good at 40 weeks) protection vs both symptomatic & severe Covid infection.(Weaker w/ Omicron, but still good.)…
How will results influence my behavior/thinking?(1/7)
a) I've been considering a Covid infection to be the equivalent of a booster in terms of protection against reinfection & severe disease (hospitalization/death). These study results indicate that it is at least that good, maybe even a bit better... (2/7)
b) We've been headscratching about why XBB variant didn't cause more of a surge, despite low uptake of the bivalent booster. It may be that immunity from all those 2022 Omicron infections kept it at bay (that's informed speculation – Lancet study ended before XBB spike)... (3/7)
Read 7 tweets
Jan 19
Covid (@UCSF) Chronicles, Day 1038
Some folks continue asking what I'm doing viz Covid behavior...
Answer: I'm changing my behavior. In the Bay Area, I'm now OK with indoor dining & removing my mask for small group gatherings.
I haven't changed, the risk has. Here's how: (1/25)
Specifically, I haven't changed my perspective on balancing prudent caution with everyone's (including my) desire for "normal."
But, in the Bay Area at least, the Covid risk has come down considerably, and, by my way of thinking, this allows for a more permissive approach.(2/25)
Where I'm coming from:
1) I'm 65 & haven't had Covid
2) I want to live as fully as I can, but am comfortable taking reasonable steps to avoid infection
3) I'm fully vaxxed & had bivalent in Sept
4) My main fear is Long Covid, which I peg at ~5% probability per Covid case. (3/25)
Read 25 tweets
Dec 27, 2022
I appreciate all (or, at least most) of the feedback on yesterday’s post regarding how I make decisions about Covid risks and mitigations, including my 50% Rule.
A brief follow-up thread today, with a few additional thoughts and responses: (1/12)
a) First, of course we’re entering year 4 (!) of Covid (I mistakenly said year 3 in yesterday's first tweet). Sorry.
I was hoping that by now Twitter would have added an edit function, but the new management seems focused on other changes. Hopefully at some point. (2/12)
b) A few folks asked how masking fits into my risk mitigation algorithm.
Just as I’m comfortable doing anything OUTSIDE without a mask, I’m OK in ALL indoor spaces – incl. crowded theaters, subways, etc. – wearing a KN95. I’m also OK removing my mask briefly to eat/drink. (3/12)
Read 12 tweets

Did Thread Reader help you today?

Support us! We are indie developers!

This site is made by just two indie developers on a laptop doing marketing, support and development! Read more about the story.

Become a Premium Member ($3/month or $30/year) and get exclusive features!

Become Premium

Don't want to be a Premium member but still want to support us?

Make a small donation by buying us coffee ($5) or help with server cost ($10)

Donate via Paypal

Or Donate anonymously using crypto!


0xfe58350B80634f60Fa6Dc149a72b4DFbc17D341E copy


3ATGMxNzCUFzxpMCHL5sWSt4DVtS8UqXpi copy

Thank you for your support!

Follow Us on Twitter!