Age-targeted strategies are often interpreted in extreme ways: "cut off", "perfectly segregate", etc, some part of society, while everyone else "gets on with normal life".
Obviously in this formulation, skepticism is merited. Nothing is perfect, and "cutting" things off...1/9
But this is an absolutist interpretation of ideas which should, like most, be interpreted quantitatively. The same misinterpretation could be given for all current strategies, by suggesting that masks, restrictions, etc., aim to "perfectly" stop all transmission. 2/
In fact, the goal of current strategies is to have a quantitative effect on transmission, reducing it for all groups essentially "as much as the market will bear".
In practice, this has involved implementing policies which begin harshly (lockdown), and gradually relax. 3/
Even during periods where policies are constant, individual stamina for mitigations is a finite resource, and we should expect compliance with mitigations to begin decreasing essentially as soon as they begin; indeed we see this directly in movement/social data, and see...
the results in case trajectories. Even when epidemiologists or public health officials hope politicians maintain constant low transmission levels until an effective vaccine is available (because of decreasing compliance, this may require ever-increasing restrictions!), 5/9
this hope should not be the basis for policy.
Age-targeted strategies recognize that when an increase in transmission / cases is in our future, COVID mortality can be decreased by making that increase happen earlier (on average! not perfectly!) for younger age groups. 6/9
Intuitively speaking, it is better for older groups if cases among younger groups occur earlier, before transmission increases have occurred among older groups as well.
It is better, for example, if in-person work begins earlier (on avg) for younger than for older people.
7/9
Quantitatively speaking, this phenomenon can be exhibited in models which incorporate known contact patterns by age (below, for the U.S.) 8/9
This kind analysis does not assume "perfect segregation" or unattainable ideals of separation.
Instead, what it shows is that making transmission increases happen earlier for younger people than for older people will reduce mortality (especially for older people).9/9
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The Bangladesh trial was a big lift and to date the only cluster randomized trial of masks to generate any publicly available data. Another pre-registered trial in Bangladesh by the same authors was suspended, and a pre-registered trial in Guinnea-Bissau never reported.
2/4
This unfortunately leaves us reading the tea leaves in this one completed study.
The ONS survey tracks reinfections through surveillance testing among its random sample of participants. Even though the recent Omicron waves, the observed reinfection rate has been 1 per thousand or so days.
As a growing number of people criticize continued restrictions on children and young people, the responses hurdled back are not defenses of still concealing faces from weeks-old infants or making 6 year olds eat lunch silently and wear masks while they learn to read, but this: 1/
Some are pure-style assertions that "these people are bad, dying is bad, COVID is not over, I am on the other team".
Others have gone full-blown connect-the-dots conspiracy, trying to uncover the mystery of why people care about young people's day-to-day experiences.
2/6
What I have not seen from many in the past months is a full-throated defense of the specific policies that children (and babies) are being been subjected to.
Who's for it!? Anyone? Or are we all against it, but sure that some of us are bad people against it in the wrong way?
3/6
1) The new phase of the trial still doesn't have any placebo intervention (like, say, education only).
One of the things our re-analysis of their previous study showed is that staff and participants were subject to big differences in study behavior. 2/8 arxiv.org/abs/2112.01296
The study found much larger effects on physical distancing than on COVID; in general, it seems likely that intervention villages are considerably more "COVID aware".
If we really care whether masks are actually helping, comparing, masks+education to education would make sense!
/
In the pandemic's 1st year, failing to focus resources and attention on the oldest+most vulnerable in society meant young people faced excessive restrictions that were senseless from a public health perspective.
In the 2nd year, it meant inordinate levels of preventable death.
As it discusses, the trials for a 2 dose vaccine in 6 mos-5 year olds failed. But now the FDA seems keen to just grant emergency use authorization anyways, while data from trials of a 3-dose regimen are still a ways out.
The next thing to watch for will be mandates for under 5's, for a vaccine under emergency use authorization in a low risk population whose only trial failed.
Meanwhile the US has some of the lowest vaccination and booster rates among the most vulnerable populations.
2/
I think it's a mistake to miss the connection between these.
We have confused people about risk, needlessly politicized our response, and tried to distract from crucial policy failures among high risk groups with policies aimed at children and young people.
3/