Thread by @DearPandemic

1/ Q: What do you think of the idea of “focused protection” or “shielding” the vulnerable so that everyone else can get on with normal life?

A: We *wish* it were this easy, but sadly it’s not.

2/ While this approach sounds appealing on the surface, the deeper you dig the more the argument folds in on itself.

Let me explain...

3/ 👉The death and hospitalization toll even in under 65s would be staggering

👉No consideration of waning immunity and re-infection

👉No mention of impact of “Long Covid” for millions infected

👉Cordoning off of a large percentage of the population is not feasible

4/ The stated goal of the “focused protection” policy is to protect those who are vulnerable by “building up natural immunity” among the rest of the population.

Let’s pretend there is a magic world where the almost 51 million Americans > 65 can live in a protective bubble...

5/ Next let’s assume that to achieve the high level of population immunity required to protect those vulnerable later on (as part of the population would stay susceptible), you would need 80% of those < 65 in the U.S. to be infected.

6/ Let’s remember that while risk of death from COVID-19 rises steeply w/ age, many < 65 still die. At current estimates of age-specific infection fatality rates (IFRs), the expected number of U.S. deaths UNDER AGE 65 with an 80% infection rate would be…

approximately *357,564*

7/ This is almost as many American deaths as in World War II (~405,000).

But let’s acknowledge that even the best bubbles are leaky. With the high levels of infection desired by this strategy, some infection is bound to spill over to the "vulnerable."

8/ What if only 10% of over 65s were infected, which would seem like quite successful “shielding” overall?

A 10% “spillover” infection rate in the over-65s would lead to an *additional 396,000* deaths in the over 65s.

9/ All told, attempting to end the COVID-19 pandemic quickly via the BEST CASE scenario of 80% infections in those < 65 & 10% in >65 & over leads to over 753,000 expected deaths, almost the equivalent of 2 American World War IIs & almost 1/2 of those deaths UNDER age 65.

10/ The # of hospitalizations & ICU admissions would be many multiples of these death numbers.

But that’s the *best-case* scenario if everything goes as planned. This plan does not account for (or even mention) the unknowns of duration of immunity & possibility for re-infection.

If immunity is short-lived, a continuous supply of new susceptibles may keep this protective immunity perpetually out of reach. Vaccine induced immunity, on the other hand, can produce more robust & durable immunity than natural infection:

https://twitter.com/VirusesImmunity/status/1308159666317340673?s=20

@VirusesImmunity

12/ The strategy does not acknowledge AT ALL any risks of COVID-19 to younger people beyond death. But COVID-19 affects not only the lungs, but also the heart, kidneys, blood vessels, & possibly the brain. @Dr2NisreenAlwan @trishgreenhalgh go.nature.com/3jR8S90.

13/ While we don’t have good estimates of the prevalence of “Long Covid” yet, the mounting evidence of long-term health effects should give us pause before *actively seeking out* widespread infection among the young. medium.com/@mlfrisco/what…

14/ If 80% of young people <35 are infected and *only* 2% experienced chronic Long Covid, this would be 2.4 million young people in the US with potentially debilitating symptoms requiring continued health care and hindering their ability to work and participate in society.

15/ The idea that large segments of society could be sealed off from the rest of society is difficult to imagine in practice & supporters of this approach have provided no details on how this magic could be achieved.

16/ @BillHanage likens the strategy to protecting antiques in a house fire by putting them all in one room, standing guard with a fire extinguisher but simultaneously fanning the flames. This doesn’t end well- but instead of your antiques it’s your loved ones.

17/ Finally, it is a straw man argument to claim our COVID options are ‘majority back to normal’ vs ‘lockdown.’ While life is far from pre-COVID, many activities have resumed, but people are also taking voluntary precautions.

18/ Remember the stated goal of the “focused protection” strategy is to achieve a high level of infections among the non-shielded group. With the virus running wild and hospitalization and deaths piling up even in the so-called “non-vulnerable”....

19/ ...it’s unlikely that a large percentage of people will be rushing back to public spaces, meaning the strategy would fail to achieve its goal of resuming economic and social activity.

20/ Proponents of the shielding approach assert that natural immunity is the only way out of this pandemic mess. They imply they would like the virus to spread quickly to achieve this-ALMOST AS IF IT WOULD BE IDEAL IF YOU COULD INJECT PEOPLE WITH THE VIRUS TO SPEED UP THE PROCESS

21/ We may be months away from such a solution-called a vaccine- but with the benefit of hundreds of thousands of avoidable hospitalizations & deaths compared to “natural” immunity.

22/ Strangely, the proponents of the "focused protection" haven't discussed why certain disease & death for many is preferable when promising vaccines & treatments are in the pipeline.

23/ Finally, this is a complicated issue worthy of open & honest discussion, but this “debate” is mischaracterized by a minority seeking headlines. Few in public health are advocating a return to lockdown & all are concerned with the indirect effects of lost jobs & education.

24/ We should all be discussing the trade-offs inherent in specific policies going forward and do our best to prioritize essentials such as schools & health care while supporting those individuals and industries taking the biggest economic hits.

25/ But the reality is that the countries that have returned almost to “normal” are the ones that managed to suppress the virus to low levels through aggressive testing, track and trace and a combination of other preventive measures (bit.ly/2IjXmFg).

26/ The path to “natural” immunity leads to both death AND economic destruction, one way or another.

27/ There is a better way. Continuing to #StaySMART & minimizing transmission along with a commitment to improve our test, track and trace infrastructure can go a long way to getting us to the happier version of this ending.

/28 It won’t be easy, but we can do a lot better than closing our eyes and hoping we can just...

Source for age-specific infection fatality rates used in calculations above: medrxiv.org/content/10.110… (Table 3)
US age-sex population estimates:
bit.ly/3iRbGlh

wired.co.uk/article/great-…

theguardian.com/world/2020/oct…