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sciolycaptain t1_j9u48fn wrote

Reply to comment by Ch3mee in Does the common flu vaccine offer any buffer against H5N1 (Bird Flu)? by Esc_ape_artist

Making influenza vaccines is something the world has experience and capacity to do (because we do it every year), however current techniques still have a bit of lag between identifying a novel strain and then development and mass manufacturing.

If we looking at the 2009 H1N1 outbreak, it took about 6 months to have a specific H1N1 vaccine approved and distributed after the first human cases.

With mRNA vaccines, which they are looking into for influenza, the turn around time may be significantly shorter.

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DiceMaster t1_j9u7jlq wrote

How long can flu vaccines last in cryo storage? Could it make sense to have tons of h5n1 vaccine stockpiled just in case?

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sciolycaptain t1_j9u8fp0 wrote

Influenza vaccines can't be frozen without having decreased efficacy. They have a narrow window of temps they can be stored in a refrigerator, and once room temperature, must be used within 72 hours.

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DiceMaster t1_j9uahwa wrote

"Cryo" may not have been the exact word I was looking for. How long do they last, sealed and in a fridge?

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boooooooooo_cowboys t1_j9uqop3 wrote

I don’t know that there is much solid data to address that question. Typically flu vaccines are tailored to whatever strains are circulating in a given season, so they’re just thrown away at the before the next flu season.

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aphilsphan t1_j9urj8k wrote

There will be solid data somewhere, and generally an expiry date on the label. The manufacturer would have done or sponsored shelf life stability tests.

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xanthraxoid t1_j9uyoii wrote

It's worth noting that these tests aren't completely comprehensive. Recall that the nominal shelf life of various Covid vaccines was extended a couple of times - the initial results were interpreted conservatively, but over time more evidence allowed a more confident prediction of a longer shelf life.

When it comes to a vaccine that's not expected to be useful more than ~6 months into the future (nobody's taking the flu jab in the spring, and next year they'll want the new one) there's not really much point in measuring how it lasts beyond that with any degree of rigour.

Providing the shelf life is expected to be good enough for "this year's flu season" (3 months?) they'll most likely just use that figure and move on to more valuable work.

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NotAnotherEmpire t1_j9u8ok4 wrote

Tons, no. We don't know what the antigens of a future pandemic strain would be.

The USA does try to keep an updated stockpile of H5N1 vaccine, at least enough for doctors, first responders and the armed forces.

https://pubmed.ncbi.nlm.nih.gov/28554058/

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DiceMaster t1_j9uazju wrote

> The USA does try to keep an updated stockpile of H5N1 vaccine, at least enough for doctors, first responders and the armed forces.

That's sensible. Do we know how effective the h5n1 vaccine is, given that bird flu is so rare in humans to begin with?

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NotAnotherEmpire t1_j9vtck8 wrote

We don't "know know" because the infections are so rare and the virus is so dangerous. This is not a virus where one would do human challenge tests.

We do know what a successful flu vaccine match looks like though, and in animal tests (like the one linked) it shows what we want to see.

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The_RealKeyserSoze t1_j9uak8y wrote

We don't really stockpile flu vaccines because influenza changes and so older versions would not be very helpful. Instead we stockpile the raw materials and production capabilities for the vaccines. The traditional flu vaccine is made using chicken eggs infected with the virus so many countries have their own emergency supplies of chickens/eggs for this purpose.

Now that we also havecell based flu vaccines that don't require chicken eggs as well as future mRNA based flu vaccines that can be rapidly mass produced there will likely be a variety of of options for stockpiling/emergency preparation.

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xanthraxoid t1_j9uyz4e wrote

Emergency Chicken Stockpile is a combination of concepts I didn't expect to encounter today...

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Whiterabbit-- t1_j9uhkgw wrote

why is mrna shorter time to market?

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BlueOmega169 t1_j9ulafx wrote

The development pipeline is substantially shorter, if you can produce an mRNA vaccine you can theoretically produce any mRNA vaccine. Once you have the genetic sequence of the strain you're interested in, preparing one mRNA transcript is (more or less) the same as preparing any other. The same is not true for protein expression or live attenuated virus preparation. Preparing the vaccine at scale faster means getting to testing sooner, and testing sooner means results sooner.

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sciolycaptain t1_j9uoxo9 wrote

The current influenza vaccines are made by incubating the virus in fertilized chicken eggs. That step takes time. and hundreds of millions of eggs.

With mRNA vaccines, you can just throw templates, nucleotides, and enzymes into a container and get more mRNA for the vaccine (extremely oversimplified)

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LonelyGnomes t1_j9vb0nr wrote

I feel like that’s exactly how I’ve done PCR every time (plus some buffer and magnesium). It’s kinda magic.

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gwaydms t1_j9ulttt wrote

>2009 H1N1 outbreak

I caught that before the vaccine came out. It made me pretty sick (fever, chills, headache, dry cough). My symptoms were typical for that strain. And it was summer, not exactly prime flu season.

In those early days, brain and/or lung involvement was causing severe and even fatal disease and I didn't have that. I stayed in bed and just rode it out.

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ThellraAK t1_j9uw5u9 wrote

Isn't most of the delays in it regulatory stuff?

There were people DIYing COVID-19 vaccines as early as July 2020

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Chemputer t1_j9xmjgs wrote

Pretty much. It's one thing if you are confident enough in your own work to dose yourself, but you definitely want to know the efficacy and safety profile before you dose millions of people with it, so we do kinda need the regulatory stuff, even in a pandemic we still had essentially the bare necessities of it. I'm convinced that it was slower than it could've been at "bare necessity" speed because they were also proving the safety and efficacy of mRNA vaccines for the first time, so in the future we wouldn't need to go as slow.

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Ch3mee t1_j9uj9nh wrote

I was responding to a post saying there is already an H5N1 vaccine developed. I don't know if that's true, but its not that unbelievable it could be. My point is that if the H5N1 vaccine is already developed, then that significantly shortens the timeline. The lag just becomes the manufacturing ramp, but that can be retooled fairly quickly, and supplies can start moving almost immediately. The lag will be from the first people to get a dose to supply for the eventual demand. That can be slow, but with some planning and foresight, batches of vaccines can be deployed following patterns of outbreak. Basically, instead of months, vaccines could start hitting problem areas in days if there is already some inventory or weeks as production starts on an approved formulation.

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IslandDoggo t1_j9ur288 wrote

Part of what made covid a problem was it being novel. H5N1 means a lot of awful things for us, potentially. But it is not novel. We know this enemy.

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PhoenixReborn t1_j9vbscq wrote

Flu strains mutate rapidly. That's why they're updated and administered every year. We have a vaccine, but it hasn't been designed for the current sequence. The typical turnaround time for the annual flu vaccine is six months.

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