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Mar 1, 2022·edited Mar 1, 2022Liked by Katelyn Jetelina

Thank you, THANK YOU, for bringing up micromorts. I learned about them in grad school in the 1990s and taught grad courses on them for 12 years. It's a really helpful abstraction and I'm more dismayed than surprised that no public figure I know, in the press or in government, has brought it up in this context.

One tiny thing to add : just being alive and at a certain age has a micromort value. For me at age 56 my baseline micromort value is 7 per day. For my 20-year-old son it's under 2. When I retire at 67 it will be about 18 and only goes up. So. One really intuitive comparison would be that catching Covid makes my daily micromort value equivalent to that of someone in their 90s. My son catching Covid brings his micromort level up to mine. And that is why he stopped masking earlier than I did.

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I'm curious about measuring COVID (and other) risks in microQALYs. For one thing, that could help people communicate about risk tolerance for long COVID.

Using microQUALYs to help people communicate risk tolerance still seems pretty niche. I know of no one other than economist and effective altruist Patrick Julius doing something like that. (I suppose others I don't know of do it, too, but it still seems unusual):

https://patrickjuli.us/tag/qaly/

I do not think it should be niche. I'm aware people worry QALYs are ageist and ableist, but I have too much personal experience with QALY reduction to fear abuse of QALYs more than inadequate use. Moreover, QALY use could drive home how subjective risk tolerance is, and how much it's influenced by socieoconomic factors. I believe empowering people to estimate and communicate risk in microQALYs could also expand people's empathy:

For example, while anyone with a given medical problem might expect a hit to their microQALYs, those with a reasonable expectation that they won't be believed, won't be treated, or won't be able to afford care if they seek it, can expect a bigger hit. Perhaps this should be obvious, but there are many analytical types (often but not always better-off men) who find it easy to dismiss effects they aren't given a framework for estimating.

Could microQALYs be that framework?

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If you are asking me, I'd be happy to have this conversation offline. 😃

I don't know substack, but I have my real and easily searchable full name up here, so find me on LinkedIn or something.

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Mar 1, 2022Liked by Katelyn Jetelina

Can you please address the recent NYT article that the Pfizer vaccine for 5-12 year olds is not very effective? For those of us with high-risk kiddos, this news feels devastating. Can you talk about how effective the vax really is, why they are removing school mask mandates at the same time as this info coming out, if a booster will be available soon and is advised, and how we should proceed? Thank you - so grateful to you.

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This is my question too. It seems likr a perfect storm- fewer masks, waning immunity, no work on kid third shot/ booster ( for 5 to 11) or booster ( 4th shot) for adults…

The risk levels you shared help, generally lower for my family than I feared but knowing the plan from here would help and feels jusr so lacking. Any news re boosters and efficacy of vaccines for kids

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One speculation is it may be that the dose wasn't high enough. That said, the comments below are worth taking into consideration.

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This article really annoyed me, because it was focused entirely on individual effectiveness. In fact a 50% effectiveness in preventing infection is pretty amazing - it's enough to cut Rt in half.

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In IL DCFS stated there’s no mask mandate anymore for daycare & preschool. Unreal

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There’s been no masks in over half of the US for months, and no different outcomes than those with masks.

Alternatively just look at many European countries which haven’t had masks on children throughout the pandemic (especially Nordic countries).

You will see it will be ok, just as it was in all those places.

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founding

"There’s been no masks in over half of the US for months, and no different outcomes than those with masks."

That's not what these 2 studies showed.

https://wwwnc.cdc.gov/eid/article/28/1/21-1591_article

https://www.cdc.gov/mmwr/volumes/71/wr/mm7106e1.htm?s_cid=mm7106e1_w%20[cdc.gov]

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D Hart, these are two poorly designed studies which found what they set out to find. There are around 150 more like them. It's a very strange time for science. Quick review of the two you linked:

"Mask Effectiveness for Preventing Secondary Cases of COVID-19, Johnson County, Iowa,"

1) It's a retrospective case control study done through questionnaires, not RCT, so at bottom tier of journal quality.

2) They estimated 50% difference, did retrospective case control study and found 50% difference. What are the odds?

3) Even accepting the design flaws, if you read the data in table 1 (https://wwwnc.cdc.gov/eid/article/28/1/21-1591-t1) their findings show the best odds of avoiding Covid is if Index patient does NOT wear a mask. This was 20% lower than if index wore a mask.

4) Setting aside this study, Iowa had among the lowest mask use for students, and despite claims in the media like "Welcome to Iowa, a state that doesn’t care if you live or die"[1] they fared no different than anyone else, again, driving home the point that despite what we hoped, very little (if any) of our mitigation strategies had any demonstrable benefits without running them a case control study so we can data drudge and p-hack.

For the other study:

"Effectiveness of Face Mask or Respirator Use in Indoor Public Settings for Prevention of SARS-CoV-2 Infection — California, February–December 2021"

1) This study was lampooned so hard by left, right, and middle on mask debate that the author had to make her twitter bio private after pushback (which is sad, I wish people would be more civil). But seriously, that is a terrible study.

2) I will let very pro mask Emily Oster refute this one:

https://emilyoster.substack.com/p/lots-of-studies-are-bad?s=r

____________

[1] https://www.washingtonpost.com/outlook/2021/02/10/iowa-lift-all-restrictions/

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founding
Mar 2, 2022·edited Mar 2, 2022

Thanks for your expansive reply.

Regarding your #3 and the Iowa study, the results do not show what you state. Due to the small numbers in the unmasked/masked group, and in the masked/unmasked group, the confidence intervals are wide (about 3X wider than those for the unmasked/unmasked and masked/masked groups).

The CIs for the unmasked/masked group and the masked/unmasked group (which are the groups I assume you're comparing) overlap. This means that the data presented does not show a difference between the 2 groups. There may be a difference (or there may not be), but the data presented did not show it. It certainly does not "show the best odds of avoiding Covid is if Index patient does NOT wear a mask." You are misinterpreting the results, though it is a common mistake.

To get a better idea of the effectiveness of masks using the CDC data for the Iowa study, examine the data (and, importantly, the CIs) for the 2 groups with the much greater number of cases (more than 9X) relative to the discordant groups.

For those in which both were masked, the results were 12.5 (9.6–16.3); for those in which both were unmasked, the results were 26.4 (22.9– 30.7). Note that the upper limit of the secondary attack rate for those in which both were masked was 16.3, significantly lower than the lower limit of the secondary attack rate for those in which both were unmasked (22.9), and there was no overlap in the CIs. This is consistent with the hypothesis that masking significantly reduces the secondary attack rate.

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No, thank you! I rarely get pushback when diving into these studies. Appreciate your thoughtful feedback!

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Emily has been consistently pro mask throughout her writings the last 18 months, though her enthusiasm hasn't been as pronounced probably since Omicron (this is just personal gauge of reading her substack and previously her twitter feed).

Regardless, careful falling to the logical fallacy of "ad hominen" - you are attacking the arguer (she doesn't have the credentials) not the argument itself (the study is poorly designed). By that logic should we have dismissed Katelyn writings when she rose to prominence on social media just because prior to 2020 her published papers were largely focused on domestic violence, poverty, LE, economic stressors, etc, and not on infectious disease?

Regarding the study you linked: "Mask adherence and rate of COVID-19 across the United States", the study reference period was Apr - Sept 2020, then compare to May - Oct 2020.

All claims it makes should you re-run for future dates fall apart. There are a number of subsequent studies that make a similar mistake, not realizing that the seasonality would bias results against warmer climate states when restricting to that time frame.

For reference there 700K covid cases in California during the study reference period. That number would triple within 4 months, despite California having some the strictest mask mandates and adoption rates. Or use Illinois, it *only* had 236K cases during the reference period, which is credited towards masks. But within 4 months, cases quadrupled. But in Florida, cases only doubled between Sept - Dec. Was this due to masks then?

Studies like this, if their claims are falsifiable, should produce the same results when date ranges are adjusted (i.e., you should be able to reproduce the claims regardless of the 5 month window of time you choose). In this case, it fails that replication test.

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Thank you, as always, YLE. I am curious for risk calculations for people with immunodeficiencies or taking immunosuppressant drugs for their underlying conditions. Even the CDC seems to have backed away from any advice on this topic and direct people to their physicians. Of course we are wearing KN95's when we must go out anywhere, still working from home, getting the additional doses and boosters recommended by the CDC, and try to avoid exposures to anyone as much as possible. But with masking becoming less used by the population in general (even before the new guidance from the CDC when risk levels were more elevated), are we able to see any SAFE "off ramp" for people with immunocompromising conditions? We still don't know even if the vaccine doses and booster(s) have much effect for an individual with immunocompromising conditions. Is there any new news?

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Yes - this!

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I added MM information about immunosuppressed people to the Relative Risk Tool I made in response to questions on this post. www.covidtaser.com/relativerisk. Right now the tool has risk of death given infection given your age and immune condition. It does not have a way to predict how effective vaccines are for different conditions yet, so it lists estimates for unvaccinated people. Hope this is somewhat helpful. There is a toggle button on the tool that turns on the X in a million (MM) estimates.

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Mar 1, 2022·edited Mar 1, 2022

Thank you so much for this thoughtful post. With respect to risk being multidimensional and complicated, I am SO G--D-- SICK of hearing about the risk to "healthy, vaccinated adults" that I could literally cry. My husband is on Ocrelizumab, so we've been told to act as if he is unvaccinated. Current data, including a leading study in which he participated, says he may get anywhere between 20%-70% of protection from the vaccines (not counting the 4th shot, which he recently received), with no way to know at which end he might fall (or how the 4th shot changes that). Even trying to think about this stuff makes me want to just give up and never leave the house again. Thank you for providing tools for everyone to think about this stuff in a more practical way.

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Mar 1, 2022Liked by Katelyn Jetelina

Thank you as this has taken such a toll on my mental health thinking about keeping my family healthy and safe.

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I can relate. Every single situation I’m in I feel I have to assess now that some mitigation strategies are waning. It’s exhausting. I’m tempted to just keep on. For two whole years I had not one cold or flu. Now that’s something to get on the bandwagon with.

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YUP -- I'm just hanging on by a thread.

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"Risk calibration is incredibly complicated and hard to do. " But wearing a mask is not. Nothing beats the ease of protection. Why roll the dice if you don't have to?

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I think part of the reason is that masks don't provide perfect protection (but they sure beat no mask!), especially if not properly-worn KN95 or N95, or if others aren't wearing masks. I wonder if there's evidence about how much being fully vaccinated (+/- boosted) protects OTHERS (compared to not being vaccinated)? In other words, by how much does transmission reduce when one is vaccinated (independent of wearing a mask)? Trying to think of a nonambiguous way of asking this question - it stems from wondering how well "just" being vaccinated reduces transmission to others?

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I've learned how to wear and handle masks and they work. Protection is pretty close to perfect. If you don't work in a high viral environment such as a hospital covid ward, you're pretty well protected against the silly mistakes us civilians periodically make. A mask is, for me, the major part of protection backed up by vaccination and boosting and behavior (nothing indoors without a mask). Being vaccinated alone is not enough. I started to see that in May of 2021 in the results from Singapore. LOTS of cases of transmission through double vaccinated Pfizer people. That just re-affirmed my earlier science-based decision to keep masking after vaccination.

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I agree - It may be quite awhile before I give up wearing N95s indoors or crowded outdoor spaces (fortunately I like 'em tight with 2 straps). And...is it unusual that vaccinated people seem (as far as I understand it) to be able to transmit virus fairly easily if infected? Is this the way it is with measles and polio? Or does SARS work differently in terms of being able to transmit if infected? To the extent that vaccinated people can still transmit virus, what is the point of vaccination mandates (especially outside healthcare settings) - asking this curiously

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Mar 2, 2022·edited Mar 2, 2022

Vaccination mandates help protect hospital systems from collapse and not all vaccinated people pass on infection if they acquire one. The level of suppression their body mounts may just snuff it out quickly. And here's a fascinating look into people who never get infected no matter their exposure level: https://www.theguardian.com/world/2022/mar/02/scientists-seek-to-solve-mystery-of-why-some-people-do-not-catch-covid

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The risk rates in my area are a little higher than I expected reading this, so I may wear a mask more often. But admit that my glasses fogging up and non-native English speakers having trouble understanding me are two big reasons why I started reducing my mask wearing when our state mandate was removed a few weeks ago. It definitely isn't a simple pro/con calculus at times.

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We all have our pain points.

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Thank you so much for this, especially:

"The trauma from losing someone close to you or losing millions in a community can impact risk calibration."

I lost my dad to COVID-19 in mid-2020 and, yes, the trauma of that greatly impacts my day-to-day decisions on masking, staying home, etc.

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Wow! This is the most effective piece of science communication I have read putting risk in perspective. I continue to be infinitely grateful for your effort on this newsletter. Thank you!

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Thank you for doing this! This is extremely valuable in terms of assessing risk. One question/point: The risk of death in the article is per COVID-19 infection, but the risk of hospitalization is per 100,000 population. I don't think these things are comparable in assessing risk. It might be more useful to pull data on hospitalization per COVID-19 infection, as you did with the data on death per COVID-19 infection. Here is one source for under 5 COVID-19 infected hospitalization data:

https://www.medrxiv.org/content/10.1101/2022.01.12.22269179v1

I've seen other, pre-Omicron data from UK NHS (sorry no easy link) that agrees with the study above in terms of hospitalization per case of children under 5 with a COVID-19 infection.

The other issue I see is equating COVID-19 pediatric hospitalization per population, in a time with serious safety mitigations (masking, social distancing, distance learning), to pediatric RSV and flu hospitalization from 2003-10 with no mitigations in place. I'm not sure we have pediatric hospitalization data for flu and RSV over the last two years, so it's tough to compare these directly.

However, we have some data on RSV and flu activity over the last two years. This chart shows that flu and RSV activity dropped to almost nothing during the COVID where we know the COVID hospitalization rate (at least per population, and possibly per infection):

https://www.cdc.gov/mmwr/volumes/70/wr/mm7029a1.htm#F2_down

Another very imperfect way to compare flu vs COVID-19, considering COVID-era safety mitigations, is to compare mortality during the COVID-19 pandemic. Hospitalization isn't death, and the flu hospitalization rate might be similar to COVID-19 even if mortality rates are far lower. That being said, in comparing the last few years, with safety mitigations in place, pediatric flu deaths dropped to single digits. CDC reports seven pediatric flu deaths over the last two years.

https://gis.cdc.gov/GRASP/Fluview/PedFluDeath.html

Total pediatric COVID-19 deaths during the same period, with the same mitigations, are at least 990 (and I believe there is a time lag in this data, meaning the count is low):

https://data.cdc.gov/NCHS/Provisional-COVID-19-Deaths-Focus-on-Ages-0-18-Yea/nr4s-juj3

So again, I think equating RSV and flu without safety mitigations to COVID-19 with mitigations is problematic. That being said, the RSV numbers are so much worse that it seems reasonable to believe RSV may be equal to or worse than COVID in terms of hospitalization.

Again, I very much appreciate the perspective and I think the risk data is extremely helpful for people to read.

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Do you have any data using MM for immunosuppressed and/or pregnant people? Thank you for all you do!

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I'm going to try to figure this out for you and follow up with Katelyn! Its a hard question!

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https://www.nature.com/articles/s41586-020-2521-4: is one article I've read so far trying to answer this. It says that immunosuppressed people have double the risk from COVID-19 as others of a similar age, bodyweight and activity level. The thing that is hard is that this study was for unvaccinated people, and it lumps many different conditions together and I've been finding other studies that show different types of immune suppression have different impacts on risk. I'll keep going.

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I added MM information about immunosuppressed people to the Relative Risk TOol I made in response to questions on this post. www.covidtaser.com/relativerisk. Right now the tool has risk of death given infection given your age and immune condition. It does not have a way to predict how effective vaccines are for different conditions yet, so it lists estimates for unvaccinated people. Hope this is somewhat helpful. There is a toggle button on the tool that turns on the X in a million (MM) estimates.

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Katelyn - you are a gift. You are data driven combined with common sense and lots of smarts. This is EXACTLY what I needed at the perfect time and you are the only one doing this kind of analysis. I’ve forwarded it to so many people. Know that what you do (and have done) really makes a difference in so many lives. 🙏🏻♥️

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Would you consider (with kn94 masks) flying, going to a Broadway show, or Disneyland safe right now? Long Covid is a really big concern of mine right now too because I already have chronic migraines.

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I like the normalized risk unit (MM)!

Is there any more granular age data for MM risk? It seems like the risk rises so sharply from age 49 to age 50 that it's not telling the whole story. My guess is that the younger cohort pulls the number for age 49 down pretty heavily, and the older cohort pulls the number for age 50 up. It would be useful to break those two categories into at least three, IMHO, e.g., 18-44, 45-55, 56-64.

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I agree - I'd love to see this additional breakdown as well!

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www.covidtaser.com/relativerisk tool has risk that varies smoothly by age. The problem we are trying to fix though is that covid has changed since the data that informed the risk estimates was collected. The 19 and Me Risk calculator allows you to vary ages smoothly, and is more updated, but doesn't output information in MM like the first suggested tool. I can convert percents to MM if you want though and explain it in a reply.

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Shamelessly Bayesian approach: try a linear interpolation in each age bracket.

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YLE, you are a rock star. This is just what hubby and I have been needing to evaluate our risk of re-entering the world. (We have been practicing what we call extreme social distancing for the duration, except for those few glorious months last summer post vax and pre-Delta. This means we don't go inside public places unless we have to, we wear N95 when we do, and we do not socialize except over Zoom or few outdoor get-togethers with other vaxxed/boosted folks.)

Does extreme caution actually leave folks more vulnerable once they start gathering again with family and friends, because it's not likely they have had *any* exposure to SARS-CoV2, let alone a viral load enough to make them sick?

Also, my family doctor practically recommended that healthy, vaxxed/boosted folks go out and get Omicron. What are your thoughts on this? We are concerned about long COVID and are not at all worried about severe illness or death -- especially not after reading your post! We just don't want to live the rest of our still-active years (we're in our late 50s/early 60s) fighting a chronic illness.

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A good test for whether an idea (A) is awful is to see if there's another awful idea (B) that's better than awful idea (A). Here, "going out and sneaking in another booster" is better than "deliberately getting infected."

The other aspect is that given the way case rates are plummeting, getting infected on purpose right now is pretty damn hard. And since lots of places still have rules in place that make getting infected rather life limiting, why chance it? It's one thing to tell people "Avoiding Covid doesn't need to be the highest priority in your life any more", but deliberately catching it? Dumb advice, and good luck with that.

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I think you are right, but it is a message that some people are trying to put out -“we are all going to get it anyway…declining immunity… get it now while it’s Omicron” etc,etc. I’m not really that keen on getting flu, either, and I wouldn’t go out of my way to cosy up to anyone with that. On the other hand, I’m willing to take the risk cuddling my grandchildren, and the way things have been here in the uk, I’d be surprised if they haven’t had it twice each already.

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Full disclosure, I'm definitely in the "avoiding Covid is no longer my highest priority" camp. Took me a while, though.

Next time someone suggests getting Covid on purpose, just answer: "You first."

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I have the same question about “deliberate” exposure to COVID. I have an underlying long term health condition which I don’t want to deteriorate. Over the last few days I’ve begun to feel that the next Horseman of the Apocalypse is thundering towards us, and I’m having a hard time calculating the risk of that, too!

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founding

Your explanations are clear and very helpful. It is very important that in the future you make an effort to break down risks by race and class because morbidity and mortality are well known to be dependent on those factors.

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As always, your posts are well sourced, easy to follow and have lots of helpful visuals. I have 2 concerns. My first centers around the “stealth” Omicron sub-variant, BA.2. Reportedly 30% more transmissible it is now in all 50 states and seems to be increasing in percentage of new cases. How do you think this will impact individual risk assessment and community transmission given the large number of home antigen tests used to determine an individual’s status. Let’s face it, only a small percentage of these folks are reporting positive tests.

Secondly, those of us in healthcare received our boosters starting in mid-October. We are now greater than 4 months out with vaccine effectiveness on the wane, as demonstrated in some studies. Do you have any sense that VE will be sufficient enough going forward?

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Yes -- I am about 6 months out now from my booster and I'm not technically immunocompromised, but I have a mild case of Diabetes 2 and a few other 'high risk' conditions (which seems to be most things, including anxiety/depression) so I'd LOVE some guidance on if I should grab another booster or if I'm protected.

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Absolutely no sign of trouble here in my Metro Atlanta county. Rock solid steady decline since the peak. Nary a wiggle in the rate of decline.

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