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All-Consuming: Zombie Science Recap
So that zombie fic had a lot of scientific content. And a lot of unscientific content. This post is a pretty casual overview of the science and sci-fi relating specifically to the zombie infection.
Use this as you see fit. I've marked out three different sections which only have spoilers through the end of a given chapter, so, if you like, you can check in after chapters 6, 8, and 10 to keep up with the new stuff that's been revealed (just be careful with your scrolling). There are no spoilers for chapter 11 and beyond in the post, but there may be some in the comments.
Questions and thoughts are welcome even if you haven't read the whole fic or the whole post. I can't promise I'll have answers, but I'll try! There's some sci-fi stuff in the fic that I haven't touched on here; feel free to ask/comment about any of it. Much of it is science-shaped magic, but I'm happy to explain my magical logic.
This stuff is well outside my field of study, and this post is intended as a one-stop reference to accompany All-Consuming, not as an academic resource. (I've been too lazy to even cite any sources, so.) Please, please double-check anything I've said here before repeating it in any serious context. This post is also subject to editing. If you notice anything I've gotten wrong, or anything that's super confusing, please let me know.
Chapter 6
Transmissible spongiform encephalopathy (TSE)
This is a family of diseases in which the cerebral cortex becomes riddled with holes, hence the name. (Spongiform encephalopathy = sponge-lookin' brain disease. Doctors.) Many different animals can get these. You might be familiar with mad cow disease, chronic wasting disease in deer, or scrapie in sheep. Or Creutzfeldt–Jakob disease, kuru, or fatal familial insomnia, which are TSEs of humans.
Each causes somewhat different symptoms, but you can imagine that if your brain is going to Swiss cheese, shit is gonna get weird on the way to your inevitable demise. Some of the symptoms of TSEs in humans include personality changes, dementia, loss of coordination, tremors, hallucinations, and psychosis. Some of the symptoms in animals are even creepier than that. Chronic wasting disease is nicknamed "zombie deer disease" for a reason.
TSEs progress very slowly, along the lines of months to years. The manner in which TSEs are contracted varies, and in some cases it's not well-understood. The one in the fic spreads via bodily fluids from an infected person getting into your bloodstream, which does happen with some real TSEs.
Prions
Scientists are pretty sure that TSEs are caused by prions, but there are other hypotheses, or it could be some combination of things. In the fic, we (meaning Shen Wei and I) assume that the TSE in question is caused by a prion.
A prion is a misfolded protein. It's made of the same stuff as a protein that's supposed to be in your nervous system, but it's not shaped quite right, and it causes other proteins around it become misfolded as well. As prions accumulate in the nervous system, they cause cell death and tissue breakdown.
The healthy proteins that are affected are a little different from one species to the next. They're different enough in rodents and humans that my (entirely fictional) rodent prion disease doesn't affect humans. Except that it obviously does. But it shouldn't be able to do anything to us.
Because prions are just single molecules, they're kind of hard to get rid of. The immune system doesn't fight them, and they're unfazed by lots of human attempts at sterilization. You can't kill a protein like you can a virus or bacteria. As a result, we don't know how to cure prion diseases, and we can't make a traditional vaccine for them either, because those rely on teaching the immune system to kill the invader.
Chapter 8
Gene editing
I'm not going to get too deep into this, because we'd be here all day, I'd probably get something wrong, and the specific details of how it works are not needed to understand the plot. Gene editing techniques in AU Dixing and Haixing aren't even quite the same as ours.
But here's the short version: Gene editing is changing the DNA inside the cells of living organisms. We (meaning people who aren't me) build the new piece of genetic information, and then we need to install it into an organism's cells. There are different ways for getting DNA into cells and getting it spliced it into the genome.
In the fic, the specific molecules that put the new gene into the strand of DNA are based on CRISPR-Cas9, which I mention mostly so you'll know what term to google if you're curious. I'll touch a little more on this below, but it's not super important to the plot. The method for delivering the molecules into cells is important, though. In the real world, we can use artificial viruses for this purpose, and that's what happens in the fic.
The zombie infection
How do you make humans susceptible to mouse prions? Replace their human proteins with mouse proteins! How do you do that? Replace their prion protein gene with the mouse version! Or close enough to it, at least. Then their body will start producing that protein, which will be susceptible to the prion. So the zombie infection has two parts: the virus, which injects gene editing tech into your cells and turns your prion protein gene all mousey, and the prion disease, which can now infect you and eat your brain. Yay teamwork! The zombie virus causes some flulike symptoms. The prion disease causes neurological symptoms.
Now, there are a bunch of things this doesn't outright explain. How do the proteins get turned over and mouse-ified so quickly? Why does the prion disease progress so much faster than normal? Why do people "die" and then come back as zombies who eat people? Well, the zombie virus isn't just messing with that one gene, it makes some other major genetic changes. This causes the accelerated zombification process (through authorly handwaving and plot necessity!)
The zombies in this fic are not technically "dead". Depending on your definition of deadness, I guess. The reanimation is part of the disease process. The prion disease eats enough of your nervous system to render you inoperable, but there's something in your new fancy genome that causes certain life processes to restart after a time. By that point, your brain is not doing what it's supposed to do. What you're left with is extreme heightened aggression towards your own species, and hunger. So. Much. Hunger.
Well, there also seem to be some traces of human behavior left, like pack hunting. It's not for me to say how much thinking the zombies are capable of, but...they can't open doors. If that's any reassurance.
Chapter 10
Immunity
So the way the gene editing tech in this fic works, once it gets into your cell, is that it targets a specific part of the genome, cuts it out, and replaces it with a new piece. (I'm just paraphrasing Shen Wei now!) The zombie virus is targeting the human prion protein gene. But the Hallow virus, to which Shen Wei was exposed when he was younger, changes the neighboring genes, among others. So when the zombie stuff got into his cells, it couldn't find the place to cut, and nothing happened.
The immunization that Shen Wei and Zhao Yunlan come up with involves making a modified virus that would change something small in the genome and prevent the zombie virus from making its edit. That would immunize the same way the Hallow virus immunized Shen Wei, but without giving anyone superpowers or causing major structural changes to the brain or any of the other wild shit that the Hallow virus did.
This gets referred to as a vaccine, which is probably a correct use of the term, but it's a totally different process to any vaccine you've ever gotten, and to my knowledge nothing like this has been tried in the real world. Editing your genome to prevent infection is obviously really extreme, but zombie apocalypses call for desperate measures.
Okay, that's what I've got! I have given myself a headache.
Use this as you see fit. I've marked out three different sections which only have spoilers through the end of a given chapter, so, if you like, you can check in after chapters 6, 8, and 10 to keep up with the new stuff that's been revealed (just be careful with your scrolling). There are no spoilers for chapter 11 and beyond in the post, but there may be some in the comments.
Questions and thoughts are welcome even if you haven't read the whole fic or the whole post. I can't promise I'll have answers, but I'll try! There's some sci-fi stuff in the fic that I haven't touched on here; feel free to ask/comment about any of it. Much of it is science-shaped magic, but I'm happy to explain my magical logic.
This stuff is well outside my field of study, and this post is intended as a one-stop reference to accompany All-Consuming, not as an academic resource. (I've been too lazy to even cite any sources, so.) Please, please double-check anything I've said here before repeating it in any serious context. This post is also subject to editing. If you notice anything I've gotten wrong, or anything that's super confusing, please let me know.
Chapter 6
Transmissible spongiform encephalopathy (TSE)
This is a family of diseases in which the cerebral cortex becomes riddled with holes, hence the name. (Spongiform encephalopathy = sponge-lookin' brain disease. Doctors.) Many different animals can get these. You might be familiar with mad cow disease, chronic wasting disease in deer, or scrapie in sheep. Or Creutzfeldt–Jakob disease, kuru, or fatal familial insomnia, which are TSEs of humans.
Each causes somewhat different symptoms, but you can imagine that if your brain is going to Swiss cheese, shit is gonna get weird on the way to your inevitable demise. Some of the symptoms of TSEs in humans include personality changes, dementia, loss of coordination, tremors, hallucinations, and psychosis. Some of the symptoms in animals are even creepier than that. Chronic wasting disease is nicknamed "zombie deer disease" for a reason.
TSEs progress very slowly, along the lines of months to years. The manner in which TSEs are contracted varies, and in some cases it's not well-understood. The one in the fic spreads via bodily fluids from an infected person getting into your bloodstream, which does happen with some real TSEs.
Prions
Scientists are pretty sure that TSEs are caused by prions, but there are other hypotheses, or it could be some combination of things. In the fic, we (meaning Shen Wei and I) assume that the TSE in question is caused by a prion.
A prion is a misfolded protein. It's made of the same stuff as a protein that's supposed to be in your nervous system, but it's not shaped quite right, and it causes other proteins around it become misfolded as well. As prions accumulate in the nervous system, they cause cell death and tissue breakdown.
The healthy proteins that are affected are a little different from one species to the next. They're different enough in rodents and humans that my (entirely fictional) rodent prion disease doesn't affect humans. Except that it obviously does. But it shouldn't be able to do anything to us.
Because prions are just single molecules, they're kind of hard to get rid of. The immune system doesn't fight them, and they're unfazed by lots of human attempts at sterilization. You can't kill a protein like you can a virus or bacteria. As a result, we don't know how to cure prion diseases, and we can't make a traditional vaccine for them either, because those rely on teaching the immune system to kill the invader.
Chapter 8
Gene editing
I'm not going to get too deep into this, because we'd be here all day, I'd probably get something wrong, and the specific details of how it works are not needed to understand the plot. Gene editing techniques in AU Dixing and Haixing aren't even quite the same as ours.
But here's the short version: Gene editing is changing the DNA inside the cells of living organisms. We (meaning people who aren't me) build the new piece of genetic information, and then we need to install it into an organism's cells. There are different ways for getting DNA into cells and getting it spliced it into the genome.
In the fic, the specific molecules that put the new gene into the strand of DNA are based on CRISPR-Cas9, which I mention mostly so you'll know what term to google if you're curious. I'll touch a little more on this below, but it's not super important to the plot. The method for delivering the molecules into cells is important, though. In the real world, we can use artificial viruses for this purpose, and that's what happens in the fic.
The zombie infection
How do you make humans susceptible to mouse prions? Replace their human proteins with mouse proteins! How do you do that? Replace their prion protein gene with the mouse version! Or close enough to it, at least. Then their body will start producing that protein, which will be susceptible to the prion. So the zombie infection has two parts: the virus, which injects gene editing tech into your cells and turns your prion protein gene all mousey, and the prion disease, which can now infect you and eat your brain. Yay teamwork! The zombie virus causes some flulike symptoms. The prion disease causes neurological symptoms.
Now, there are a bunch of things this doesn't outright explain. How do the proteins get turned over and mouse-ified so quickly? Why does the prion disease progress so much faster than normal? Why do people "die" and then come back as zombies who eat people? Well, the zombie virus isn't just messing with that one gene, it makes some other major genetic changes. This causes the accelerated zombification process (through authorly handwaving and plot necessity!)
The zombies in this fic are not technically "dead". Depending on your definition of deadness, I guess. The reanimation is part of the disease process. The prion disease eats enough of your nervous system to render you inoperable, but there's something in your new fancy genome that causes certain life processes to restart after a time. By that point, your brain is not doing what it's supposed to do. What you're left with is extreme heightened aggression towards your own species, and hunger. So. Much. Hunger.
Well, there also seem to be some traces of human behavior left, like pack hunting. It's not for me to say how much thinking the zombies are capable of, but...they can't open doors. If that's any reassurance.
Chapter 10
Immunity
So the way the gene editing tech in this fic works, once it gets into your cell, is that it targets a specific part of the genome, cuts it out, and replaces it with a new piece. (I'm just paraphrasing Shen Wei now!) The zombie virus is targeting the human prion protein gene. But the Hallow virus, to which Shen Wei was exposed when he was younger, changes the neighboring genes, among others. So when the zombie stuff got into his cells, it couldn't find the place to cut, and nothing happened.
The immunization that Shen Wei and Zhao Yunlan come up with involves making a modified virus that would change something small in the genome and prevent the zombie virus from making its edit. That would immunize the same way the Hallow virus immunized Shen Wei, but without giving anyone superpowers or causing major structural changes to the brain or any of the other wild shit that the Hallow virus did.
This gets referred to as a vaccine, which is probably a correct use of the term, but it's a totally different process to any vaccine you've ever gotten, and to my knowledge nothing like this has been tried in the real world. Editing your genome to prevent infection is obviously really extreme, but zombie apocalypses call for desperate measures.
Okay, that's what I've got! I have given myself a headache.
no subject
A question, if that's okay? How are they planning to distribute the vaccine? A standard immunisation programme will be difficult to organise under the state that Haixing and Dixing were in by the end of the story, and also not very efficient considering the pandemic state, but I can't really think of an alternative either, so. I know ZYL said something about "catching immunity from sneezing people," but...?
Also, who's going to be mass-producing the vaccine? Dixing, probably, since Haixing doesn't have the resources or the personnel to spare, but will they try to use that as a bargaining chip or grounds to stage a coup in Haixing? (Though General Lang would probably put a stop to that!)
Aaannd...those questions have nothing to do with science. Whoops!
no subject
However, I can offer up what I think would probably happen! Dixing does still have areas that haven't really been affected, so I imagine that's where mass production would be set up. They can try to hold that over Haixing's heads, but there is going to be contagion, so they can't really contain it. They could maybe engineer a non-contagious version (and maybe someone should?) but that would take a while, and they can't stop vaccinating in the meantime. That's not to say there won't be problems. Haixing has a ROUGH road ahead of it, and things are going to be politically ugly. But I do think the contagion aspect + the prevailing desire not to have zombies in your own country or knocking on your border will pave the way for the vaccine making it to the population.
As for the distribution, that's the primary thing Haixing and Dixing will want to expend resources on, so I guess they're gonna get that done by hook or by crook. In areas that are still populous, that probably amounts to setting up stations for rapid distribution and getting the word out. In many parts of Haixing, it won't be that simple anymore, and immunization is going to have to be a part of organized evacuation/cleanup/zombie-killing work. (The fact that immunization is transmissible will lead to better outcomes, although it'll probably also lead to doses being wasted on people who are already immune at some point.)
Anyway, that's just the vague image I have in my head of how immunization would happen. Hope it was interesting or helpful!
no subject
no subject
no subject
Your authorly handwaving about pack hunting and acceleration of the infection is totally okay! <3
no subject
Just had to poke a little fun at myself :P
no subject
(I deploy my Feed icon on principle.)
no subject
Hah, yes, appropriate icon is appropriate.
no subject
Also, I think we're getting really close to using viruses as vaccines...
no subject
I think we'll be able to use gene editing to treat and prevent disease pretty soon. Which opens up all kinds of ethical questions, but is exciting.