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A brief thought on the virus, CDC guidelines, and #scicomm.
Published onApr 06, 2022

Because I’ve been cooped up recovering from covid (I’m fine, it was mild, etc.), I was about to write about the glaringly obvious gap between the CDC’s current isolation guidance and the science…when I discovered that economist Joshua Gans had written almost exactly the same post, far better than I would have.

Particularly, his bit about why the CDC’s current isolation guideline that you isolate for just 5 days if symptoms resolve is utterly ludicrous:

With vaccines, Omicron works a little differently and gives you symptoms before being a danger to others and then, just as you are feeling better, it finally may get to the place where you are dangerous to others.

This may be especially true if you’re boosted. Some early studies have found that boosted people are more likely to be at their peak levels of infectiousness 5-6 days after experiencing their initial symptoms, precisely because their vaccine-primed immune systems are able to rev up so quickly.

But I’m not sure I think Gans is right when it comes to his proposed update to the guidelines:

If you develop symptoms, wait 5 days following the onset of symptoms (not exposure), get tested and if the test is negative you can end isolation. Otherwise, get tested again every day or so until you are negative.

For one, it’s simply unworkable to ask people who have any of the long list of potential omicron symptoms to wait at home for five days twiddling their thumbs and wondering if they have covid before testing. I’m as cautious and evidence-driven as they come, and I both don’t think I could wait that long nor convince my partner to isolate from me for five days on suspicion alone. For another, although I understand how he arrived there, it begs a lot of questions that could easily make people suspicious of testing. Why would it work on day 5 but not on day 4?

In a perfect world, people would just trust the experts and behave accordingly. Alas, our unfortunate reality makes this entire flavor of arbitrary day-based guidelines problematic. People aren’t stupid. They know that the number of recommended isolation days is just a rough proxy, and after seeing that number drop from 14 days to 10 to 5, they’re not entirely wrong to wonder if it’s actually maybe just meaningless. The guidelines aren’t meaningless, of course, but they’re also, for lack of a better word, flat. They just tell people to behave in certain ways, without telling them any kind of story about why, which is a shame, because stories are the best way to get people to pay attention to science.

To be clear, I’m not just talking about the narrative surrounding the guidelines, which is also infuriatingly nonexistent, I’m talking about the guidelines themselves. People tend to be naturally curious, so if you ask them to change their behavior in inconvenient ways, they’re going to start asking why the guidelines have changed even though the science really hasn’t. Obviously, the CDC’s most recent change in guidelines wasn’t much based in science, but on getting people back to work faster, which is its own special form of cruel insanity. But even if you think getting people back to work faster is worth the tradeoff of extra illness and death (and I don’t), there are surely ways of doing it that tell a clear story based in science that would be much more effective.

A guideline that helps tell the story of the science might be something like: if you feel weird, take a rapid test just before you go out to spend time indoors with others, and wear a mask if possible. Continue doing so each time you go out to spend time indoors with others until you no longer feel weird. If you test positive during that time, isolate for 10 days.

Granted, I’m not a public health expert, so by all means correct me. But I am something of an expert in science communication, and it seems like that guidance (if, of course, tests were widely and inexpensively available) would catch way more positive cases, especially boosted ones, during their infectious period by not giving people a false sense of security if they test negative during the symptomatic but pre-infectious period, while also not asking people to shut themselves in and wait five days just because they might have covid. And when people ask why, there’s a clear, logical answer based in science that’s hinted at by the guidance itself: you can feel bad and not be infectious while the virus is first developing.

Yes, of course, it’s not perfect. There are false negatives. There are asymptomatic cases where people will never test. The symptomatic-but-pre-infectious window can be incredibly short and difficult to catch, especially with omicron and boosters. But I have to think it’s better than saying “do this arbitrary amount of quarantining because we said so” or “isolate yourself for 5 days while resisting the urge to test just in case.”

Of course, this is all just me screaming into the void, because the government seems to care more about getting people back to work than saving lives, rapid tests aren’t (yet?) readily available, and the CDC has spent the last two years ruining its credibility. But what are blogs for if not screaming into voids while going insane on your 9th day of isolation trying to figure out whether you can ethically or scientifically end it based on the guidance of an organization that seems to have rather loose definitions of both?

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