I had agreed to go to a small Thanksgiving gathering (there would have been 4 of us). We figured that with windows open, knowing we are all cautious about the risks of infection, it would be safe. Then I read your latest "hunker down" article :) I shared it with the hosts and they agreed it's just not a good idea to have an indoor dinner right now with different households. For context, we don't have cars so travel would be by subway and we live in apartments so we don't have backyards. If Friday is sunny, maybe we'll eat outdoors at a restaurant. BTW, nice touch that the url to the Atlantic article includes the phrase lock-yourself-down-now (!)

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Thank you for this! I love the Swiss cheese model, but I have been pondering if there is a way to more effectively communicate a few important details related to COVID:

(1) There are three distinct "pathways" of exposure - aerosols, droplets, and fomites. Many of the risk reduction steps only address one or two of these pathways. So in essence you need to make sure you have some "slices" for each pathway. This is not well communicated by the "single pathway" model. For instance, the >6ft separation is only effective for droplets, not aerosols...

(2) I also think that along each pathway, there are three major categories -- source control (quarantine of exposed/infected individuals, etc.), environmental mitigation (cleaning surfaces, ventilation), and personal protection (masks). Moreover, some actions (do "double duty" -- e.g., masks are both source control and personal protection -- which makes them more effective!

(3) Finally, different actions have different effectiveness within their "cell" in this 3x3 matrix. For instance, temperature checks are intended for source control, but have low effectiveness due to asymptomatic transmission.

I've been struggling as to whether there is a way to effectively summarize and communicate this information in an infographic -- to encourage people to make sure they "cover all three pathways," to place their personal actions in context of community-level actions, and to understand the relative effectiveness of different actions.... or is it too late?

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Given the logic of incubation periods, surely a relatively effective time to get tested is after a pre-test isolation period, no? That is, as pre-travel/pre-gathering preparations go, the effectiveness hierarchy is something like:

two week quarantine >

one week quarantine + negative test taken late in that week >

one week quarantine without a test >

no quarantine

If so, seems like it would be useful to many people to consider that second one.

And of course this is yet another reason why we should keep pressing for approval of rapid tests for use on the same day as a planned gathering (and note the latest SF study that, IIRC, shows these catch the vast majority of asymptomatic infectious folks if taken same-day).

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