Bob Wachter is the chair of the Department of Medicine at the USCF medical center and last week he posted a pair of threads about what the Covid rates might look like in a month and how we might behave if that comes to pass (and if we don’t get another variant mucking things up). I’m going to quote extensively from Wachter’s threads because I think they contain some things that people need to hear right now.
In the first thread, he explains why an individual’s risk of catching Covid will likely be quite low a month from now:
The virus is the same, your immunity is the same, the chances of getting infected from a given encounter much the same. Yet I predict that I — and most of us — who are trying our best to dodge Omicron now will be more “open” next month. Does that make sense?
Yes! It’s all about community prevalence — basically the chances that the person next to you at the restaurant, the movie, or the store is infectious w/ Covid. It they’re not, your encounter is 100% safe. If they are, your encounter is as risky as it is today.
Today, near the Omicron peak, the odds an asymptomatic person has Covid is ~10% in most of U.S. At 10% prevalence, when you enter a room w/ 20 people, there’s an 88% chance that one of them has Covid. Do that enough times without masks and you’re going to get infected.
In a month — if cases fall to prior non-surge #’s — the prevalence among asymptomatic people may be more like 0.2% — even in less vaxxed regions, which’ll have more people whose immunity came from infection. (They should still get vaxxed for better & longer protection.)
0.2% means that the odds of an asymptomatic person having Covid=1-in-500. That room of 20 people: now a 4% chance (1-in-25) that someone’s infected. Not zero — you’ll still want to be careful if you’re at very high risk. But for most, % is low enough to feel pretty safe.
And because overall rates would be much lower, the chances of survival for those who do get Covid will increase because hospitals won’t be overwhelmed, testing will be more available, and antiviral medicines will be more available. Caveats:
Yes, the specter of Long Covid (for some, mild; others disabling) continues — maybe a ~5% chance in a vaxxed person. Some will look at those odds as being concerning enough that they’ll continue to act very cautiously. I probably won’t, but it’s an understandable choice.
And others who have lots of contact w/ very vulnerable people — unvaxxed who didn’t get Omicron, for example, or immunosuppressed - may also make different choices. That’s entirely reasonable.
And there’s also this…he’s fairly confident rates will be low this spring but perhaps not later in the year (because under-vaccinated people’s immunity from catching Omicron in the past 2 months will have waned):
As for me, this is why the community prevalence (cases, test pos %) will dominate my decisions. If they don’t plummet, I’ll keep my guard up until they do. And while I’m reasonably confident about the Spring, my confidence level falls as we move to later in the year.
In the second thread, Wachter talks about how we’ll know when the risk is low and shares how his behavior will change once that happens:
Add it all up & it’s clear that this Spring — w/ a milder virus & nearly 100% population immunity — may be about as safe as it gets… perhaps for many years. Thus I see this Spring as a time when everyone (especially those who have been extra careful for two years) needs to figure out how to navigate a far less risky landscape. (Cue the usual caveat: a new variant could easily screw things up, yet again.)
The bottom line is this: in a few weeks — when this surge ends — things are going to be as good as they’re likely to get for the foreseeable future.
Here’s how he’s going to know when his personal risk level is low enough to do some things differently:
What will my trigger be for switching to less cautious mode? It’s a bit arbitrary - there’s no bright line separating “too risky” & “not risky.” This means that others may come up w/ different thresholds.
Mine will be case rates <10/100K/day (recognizing that reported cases now underestimate case #’s due to home testing). I’d also like to see test positivity rates of <1%. (The math: when we reach a 1% overall rate in SF, that would translate to a ~0.5% asymptomatic positivity rate; or 1/200 asymptomatic people having Covid. At that prevalence, in a room of 15 folks, there’s a 7% chance that at least 1 has Covid.)
So what does that mean in terms of shifting behavior? Here’s Wachter’s personal plan w/ his acceptable level of risk:
The main questions center on indoor spaces crowded with unmasked people of uncertain vaccination status. Small indoor groups, visiting friends & family, indoor dining: all fine, without masks.
If I had school-aged kids who were fully vaccinated, I’d be comfortable without masks in school, particularly if there were a school-wide vaccine requirement and good ventilation.
My practice will be to always carry a KN95, and to don it in very crowded, poorly ventilated spaces with lots of unmasked people, particularly in parts of the U.S. or world with low vax or high case rates. I can’t tell you how crowded or how poorly ventilated, any more than I can say how likely rain needs to be in forecast before I grab an umbrella. I’ll just trust my Spidey Sense: how long I’ll be in space, how awkward wearing a mask will be, whether folks are speaking, yelling, singing, or just standing around. Does it feel scary?
At least at first, I’ll still mask on public transit (trains, planes) & shopping — crowded public spaces w/ lots of unmasked people. Once masks are no longer mandated, I don’t think I’ll mask at the hospital unless I’m seeing a patient with respiratory symptoms.
Both threads are worth a careful read to catch all the caveats and to get a full picture of his reasoning regarding risk and behavior. Hopefully reading them will give you a similar sense of empowerment and hope that they gave me.
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