Pandemic Prediction Checklist: H5N1

DirectedEvolution

Pandemic Prediction Checklist: H5N1

DirectedEvolution

1 min readFeb 5, 2023

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[anonymous]

Thanks for posting this--as I've said elsewhere, I am quite worried.

One thing I am confused by in Tufecki's op-ed (and alluded to in the "non-egg" vaccine quote from her article here) is the idea that it is somehow a problem that vaccines are dependent on eggs because layers are susceptible to infection. I disagree with this part--we have tests for birds, there is currently an outbreak now among layers, and lots have been killed, but I see no reason to suspect so many will be killed that we will not have enough eggs to supply the vaccines. Although I support moving away from eggs for animal welfare reasons where possible, I really don't see how this particular limitation will be a problem (though I definitely think the length of time it will take to scale up, including egg-based vaccines, will be too long).

DirectedEvolution

Just to make it more convenient, here's her quote:

Worryingly, all but one of the approved vaccines are produced by incubating each dose in an egg. The U.S. government keeps hundreds of thousands of chickens in secret farms with bodyguards. (It’s true!) But the bodyguards are presumably there to fend off terror attacks, not a virus. Relying on chickens to produce vaccines against a virus that has a 90 percent to 100 percent fatality rate among poultry has the makings of the most unfunny which-came-first, the-chicken-or-the-egg riddle.

I'm going to make an educated guess that these farms are screened off from contact with wild birds. However, it might be a real challenge to scale up production to the levels required to produce the billions of doses of vaccine that would be required for a vax campaign on the scale of COVID-19.

Chickens lay about one egg per day, unless they're broody. If there are half a million chickens in these facilities, it would take them 71 years to produce enough eggs for 13 billion vaccine doses.

[anonymous]

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DirectedEvolution

If you read the first sentence of her quote carefully, it does indeed require one egg per dose.

I don’t know how we’d handle the tradeoff between a rampaging 50% fatal bird flu and injecting 8 billion people with vaccine from appropriated and rush converted factory farm eggs, but it seems like an extremely bad choice to have to make.

I’m not even sure the egg supply is the most important bottleneck here. You have to grow virus in the eggs, then harvest, purify, package and distribute. Working in a bio lab myself, I am going to make an educated guess and say that converting a factory farm into a vaccine production facility would be no easy task, especially if H2H bird flu was already widespread.

CNN breaks down the production process:

https://amp.cnn.com/cnn/2020/03/27/health/chicken-egg-flu-vaccine-intl-hnk-scli/index.html

JoshuaBlake

At first glance, the framework looks overfit and over sensitive. Could you please expand on your back testing? What's its sensitivity and specificity like at different thresholds?

DirectedEvolution

Feel free to peruse my old posts at LessWrong.

Edit: Peter did the useful work, but also, Here's Why I'm Hesitant To Respond In More Depth

Peter Wildeford

I think the backtests from DirectedEvolution's data are:

1918 flu would have scored 14/14

COVID-19 13/14

1968 H3N2 Hong Kong flu 11/14

2009 H1N1 swine flu 10/14

Ebola 9/14

2022 Mpox -- debuted at 4/14, eventually rose to 6/4

DirectedEvolution

Thanks Peter!!!

One thing I'd emphasize, even though it's just a subjective opinion. I think that the points scale is OOMs, not a linear scale.

Just as an hypothetical example, imagine a disease that had everything bad listed here, except it didn't kill anybody. Obviously there would be something bad about it that was making it lead to quarantines, newspaper coverage, hospital overwhelm, and a race for treatments. But unless the typical outcome is "as good as dead," the single fact that nobody dies from it makes it seem a lot less concerning than a disease that does everything else bad and kills a lot of people.

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