Stuff You Should Know - Virus Talk with Josh and Chuck

Episode Date: October 14, 2014

Viruses are big jerks that invade regular cells and hold them hostage, making you sick while they're doing it. Learn everything you ever needed to know about viruses, including how the common cold works. Learn more about your ad-choices at https://www.iheartpodcastnetwork.comSee omnystudio.com/listener for privacy information.

I'm Munga Shatikler and it turns out astrology is way more widespread than any of us want to believe. You can find it in Major League Baseball, International Banks, K-Pop groups, even the White House. But just when I thought I had a handle on this subject, something completely unbelievable happened to me and my whole view on astrology changed. Whether you're a skeptic or a believer, give me a few minutes because I think your ideas are about to change too.

Just a Skyline drive on the iHeart Radio app, Apple Podcast, or wherever you get your podcasts. On the podcast, HeyDude the 90s called, David Lacher and Christine Taylor, stars of the cult classic show HeyDude, bring you back to the days of slip dresses and choker necklaces. We're going to use HeyDude as our jumping off point, but we are going to unpack and dive back into the decade of the 90s. We lived it and now we're calling on all of our friends to come back and relive it. Listen to HeyDude the 90s called on the iHeart Radio app, Apple Podcasts, or wherever you get your podcasts.

Welcome to Stuff You Should Know from HowStuffWorks.com. Hey and welcome to the podcast. I'm Josh Clark. There's Charles W. Chuck Bryant. There's Jerry. And this is Stuff You Should Know. Featuring my enormous, stopped up nose. And how appropriate.

Yeah, well, that was one of the reasons why I wanted to do this one. I figured. I'm a little sick right now. Yeah, yeah. Still. And I wanted to know more about the monster inside of me. That's right. Like, I'm not feeling great and the knowledge is power, like we always say.

Exactly. Like just from researching this, I was like starting to break a sweat and tremble and I was like, I'm getting better. Then I passed out and hit my head. Yeah. I didn't have enough time to finish studying, so I'm going to have to make a lot of this up, Chuck. Cool.

Yeah, we've covered Ebola recently and we are definitely going to cover HIV at some point. We just haven't gotten around to it. Yeah. But both of those are viruses. There's another one we talked about that seemed to come up in this. I don't remember what it was, but. The herpes?

No. No. We never talked about herpes. Well, you know, not mixed company. What was it? I don't remember, but there was definitely. Microbiome, maybe? Yeah, no.

I don't remember what it was, but we've talked about viruses and viral infections. But to me, I think viruses are one of the most fascinating things on the entire planet. They're jerks. Like we don't know where they came from. Yeah. We don't quite know how to classify them because they really kind of operate on the line between a living and a non-living thing. Yeah.

This article said like most scientists agree, but I found a lot of people that said that they're not living things too, so. Yeah. But who cares, really? They still definitely have an effect, you know? The weird thing is about a virus is why some people say it's living and some people say it's non-living is that to be a living thing, you have to have something like. Arms.

Yeah. You have to have arms. Yeah. Rocks. Rocks don't have arms. Nope. Point proven. Yep.

You have to be able to carry out the processes that keep you alive. Like self-sustaining. Yeah. Yeah. Like a cell. A cell is the smallest living organism. It's the smallest possible living organism because you get lower than that and you have maybe the things that make up a cell, but they can't sustain themselves.

A cell can sustain itself and things can be made up of cells like us. And therefore, we are a living organism. The cells that make a separate living organism, plants are living organisms, but viruses, they don't have any means of carrying out the processes that keep them alive, which doesn't matter because they're not alive, but more important, they don't have any processes that allow them to reproduce. Yeah. They're just like by themselves that they're not worth very much.

They need to glom on. They're always glomming on to everyone else's junk. Exactly. Which is basically what a virus does. Well, for something as simple as a virus is, and we'll talk about how simple they are in a second, they have devastating effects when they do start to really get busy. Sure. You know?

Yeah. So Chuck, I was saying, they don't know exactly where viruses came from. They know they're very old, but there are a couple theories. My favorite one, probably the one that's right, is that they were former bits of cells that basically evolved into freelance renegades. Really? Yeah. Which explains why certain viruses fit with certain cells.

Oh, well, that makes sense. So they could have just been basically like drifting genetic material that evolved enough to say, I'm going to learn to reproduce by hijacking. Renegade drifters? Yep. So are you saying that viruses are John Rambo? Pretty much. So let's talk about what makes a virus.

Yeah. Well, like you said, a cell is on its own. It can do its own thing. Viruses cannot. Viruses are super tiny, about one millionth of an inch long, which is a thousand times smaller than bacteria, which are smaller than human cells, most of them. There are some viruses that are actually larger than the average size bacteria, but for the most part they are smaller.

Which is still super tiny. Sure it is. They have an electron microscope to view these bad boys. Right. And they can infect just about any living thing. As a matter of fact, any living thing could be theoretically infected by a virus. Like a bacteria can get a viral infection. Man, that's crazy.

Isn't that crazy? I don't even know what that means. Seaweed can get viruses. Yeah. Donkeys. Yeah. All sorts of stuff. The whole gamut from seaweed to donkeys.

The virus itself, if you just want to look at what that little tiny particle is, it's a virion. Is that how we're going to say that? Virion. Virion? Yeah. Why didn't they just leave the second eye out in virion? Yeah.

I don't know. It's so much better. Basically what it is, is a set of genetic instructions. It can be either DNA or RNA, it can't be both, and it's just instructions. That's all it is. That's the nucleic acid that is part of a virion. Like a virion is like a particle, it's like an individual viral particle. And part of that is the nucleic acid.

Yeah. And that's surrounded by capsid, which is just a protein coating to protect it. And then sometimes, if it's an enveloped virus, it will also have an envelope around that capsid. If it's naked, it doesn't need or because it just doesn't have that other protein coat. Right. So those ones are enveloped with a lipid, a fat of some sort.

But for a naked virus, it's made up of two things. It's got its nucleic acid and its protein coating that protects the nucleic acid. So it's not just nucleic acid floating around. That's right. And the nucleic acid is, like you said, it's basically just a blueprint for how to make more viruses because if, speaking teleologically, a virus is its whole purpose is to make more viruses. Yeah.

That's all it cares about. And you can say, well, that applies to just about any living organism if you get down to the bare bones. Oh, just to propagate. Yeah. With the virus, it's like, that's it, man. Yeah. It's not doing anything else.

It doesn't care about playing cards. It doesn't want to do anything but reproduce. And make you sick. Yeah. Yeah. Their shape varies a lot, but they're basically three types, helical or helical, it's like a tube. You got your polyhedral, so it's sort of like a soccer ball.

And then you have your complex shapes and they are complex. They're, you know, they can look crazy. They can have tails. They can have crazy looking spider legs. Like the, what? They get both. Which one looks like the Apollo lunar lander? I'm going to go with complex.

I would guess complex. I don't know that for sure, but yeah, I don't think it could be polyhedral. It's startling. How much it looks like that. Yeah. It looks like it was made to look like a cool little lunar lander. Or that the lunar lander was modeled after the virus. Maybe.

Which doesn't make much, because they wanted to infect the moon, which we may have. Astronaut jokes. So unlike cells that can do their own thing, viruses don't have enzymes like cells do that basically allow it to operate independently as their own little units. Some do. Some viruses contain just enough enzymes to take their DNA or their RNA and do something with it to basically prime it to be transcribed or something like that. Or they have enzymes that go hijack the enzymes in the cell.

So some do, most don't. But yeah, that's the whole point of infecting a host cell. If all a virus wants to do is reproduce, but it can't reproduce, that's where the host cell comes in. That's right. They basically move into the factory with and say, we're going to use your equipment. Right. They're like, there's going to be some big changes around here because there's a new

sheriff in town. And it was to kill you. The virus. Yeah. Although all viruses don't kill people. We should point that out. No. Depending on what kind of virus it is, whether it's naked or enveloped, it will attach itself

to the host cell and either inject it. If it's naked, it has to stay outside the host cell and it basically injects its genetic material into the host cell. Or if it's enveloped, that fat lipid coating that makes it an enveloped virus basically connects to the host cell's own fat lipid coating and that protein-coated virus can basically slip through, just absorb right into the cell and say, ta-da, when it makes it on the inside. Yeah.

Is that what an antigen is? I think that's the protein that has to match. The antigen looks for another like protein so it can get that tight bond. And if they're not similar enough, they can't bond and infect that cell. Right. Be wrong on that. Is that right? I don't know if that's the... It sounds right.

The reason it sounds right is because I saw elsewhere in research that that's why viruses go after specific kinds of cells. Oh, okay. They recognize the type of cells that they're capable of infecting. Right. And say, I can bind to you very tightly, my friend. Exactly. So let's watch.

So let's dance. Exactly. So in this passage, we are going to get down to the nitty-gritty on what happens once they have bound themselves to that cell. I'm Mangesh Atkala, and to be honest, I don't believe in astrology, but from the moment I was born, it's been a part of my life. In India, it's like smoking. You might not smoke, but you're going to get secondhand astrology.

And lately, I've been wondering if the universe has been trying to tell me to stop running and pay attention, because maybe there is magic in the stars, if you're willing to look for it. So I rounded up some friends and we dove in, and let me tell you, it got weird fast. Tantric curses, Major League Baseball teams, canceled marriages, K-pop. But just when I thought I had to handle on this sweet and curious show about astrology, my whole world came crashing down. It doesn't look good, there is risk to father.

And my whole view on astrology, it changed. Whether you're a skeptic or a believer, I think your ideas are going to change too. Listen to Skyline Drive and the I Heart Radio app, Apple Podcast, or wherever you get your podcasts. On the podcast, Hey Dude, the 90s called David Lasher and Christine Taylor, stars of the cult classic show, Hey Dude, bring you back to the days of slip dresses and choker necklaces. We're going to use Hey Dude as our jumping off point, but we are going to unpack and dive back into the decade of the 90s.

We lived it, and now we're calling on all of our friends to come back and relive it. It's a podcast packed with interviews, co-stars, friends, and non-stop references to the best decade ever. Do you remember going to Blockbuster? Do you remember Nintendo 64? Do you remember getting frosted tips? Is that a cereal? No, it was hair.

Do you remember AOL Instant Messenger and the dial-up sound like poltergeist? So leave a code on your best friend's beeper, because you'll want to be there when the nostalgia starts flowing. Each episode will rival the feeling of taking out the cartridge from your Game Boy, blowing on it and popping it back in as we take you back to the 90s. Listen to Hey Dude, the 90s called on the I Heart Radio app, Apple Podcasts, or wherever you get your podcasts. All right, Josh, they moved into the cell.

They like the looks of it. It's a nice open concept floor plan, which everyone loves these days. What happens from there? Well, it depends on the virus. So let's say it was one that injected it. It's got its genetic material floating around. Maybe there's an enzyme that's assisting the genetic material. Or if the virus itself showed up, it's releasing its genetic material all over the place.

But basically, what happens is... That sounds pretty gross. Yeah. Well, it is pretty gross. Like a teenage boy. It happens exactly like you think. But once inside the cell, you'll see a lot of the virus hijacks the cell's processes. Yeah.

Like, hey, we need to use your deal because we don't have our own. Exactly. Yeah. And they're not... The reason people use the word hijack is because it really gets the point across. But it's also because science isn't 100% on how viruses do it. And what they think, basically, is that if there's an accompanying enzyme or something, the enzymes basically wait for a line of other enzymes, the cell zone enzymes, to go past.

And then it grabs the last one in the line. That old trick. Hits it over the head. Yeah. And then it uses it. Is this blazing saddles? Basically. And then sends it back out to go recruit other enzymes.

And then all of a sudden, the cell is... It's enzymes, it's workers. If you think of the enzymes as like the workers in the cell, they're all working for this virus. Sure. And the cells like, what the heck's going on? It's too late. The enzymes are focused on transcribing the DNA, which ultimately just makes more DNA

or RNA for the virus. And then assembling it with proteins that the enzymes are now making. So they're now making more and more and more viruses. It's a hostile takeover. It is. Very much a hostile takeover. That's one way to go. There's another thing called a retrovirus, which I'm a huge fan of.

Some of the worst viruses around are retroviruses, which is ironic because they actually have the softest impact on the host cell. But a retrovirus goes in, very quietly hangs around. Yeah. With their 80s clothing. Right. Yeah. Right.

HIV is a retrovirus. Sure. So it was, I think flu, flu is a retrovirus too, I think. But it goes in and it just inserts its DNA into the cell's DNA. All right. So it's like, hey, go about your business or whatever. But now there's this extra sequence that when you go over it and you transcribe it and you do what this DNA or this genetic material is telling you to do, to make, you're going

to also as a byproduct spit out viruses. So it's just duplicating itself. It is. So that's, there's a lot of different things that can go on, but it's like you said, there's a hostile takeover or the cell is tricked into making more viruses. But what happens is more and more and more and more viruses are being made within the host cell, which can be pretty bad for the host cell ultimately. Well, yeah, because eventually the virus is going to leave and they can either, if it's

a naked virus, it'll bust out and just destroy the host cell and be like, hey, I'm tired of your little apartment. I'm just going to burn it down because I'm my own thing now and I can live on my own. Or if it's an envelope virus and it'll just kind of pinch away and keep that protective cell membrane and just be like, well, fine, I'll just take my stuff and leave and you're free to do what you want. Right. Well, that's another reason why retroviruses are easy on the host cell is because all retroviruses

are enveloped viruses. So these newly made viruses just move to the outside membrane and bud off. And then what happens when they bud off or when the cell breaks open because there's so many new viruses that ruptures the cell, which is pretty horrific if you think about it. All of a sudden you're contagious. Yeah. And it's duplicating and spreading all throughout your body at a pretty rapid rate.

Yeah. Lots of these guys. So let's look at your, well, let's look at you for instance. Okay. What have you got right now? I got something, some sort of viral infection. I don't know. Just a cold.

Not the flu, probably. Yeah. Are you achy? Fevery? No. No. Feverish, I mean? Uh-uh.

So what do you, what do I have, Doc? Well, I would say you have a cold. Okay. But I had a cold that turned into a sinus infection. I may have one of those from the color of the stuff that's coming out of my nose, I would say. I'd probably have a sinus infection. Yes.

Would you describe it as khaki? I would describe it as a drab olive. Oh man. Way worse than khaki. Whew. When I was sick a couple of weeks ago, I had some serious bright, bright, almost fluorescent yellow coming out, which is all very gratifying to get rid of, either with your netty pot or just blowing your nose or whatever.

Yeah, I've been netty potting like a madman. Yeah. You know, you can overdo that when you're sick, apparently. Yeah. I can imagine because this, just the salt, too much salt up there. And I think just fluid, like unless you really, really get it all out, it's better, like, you need to dry out completely in between. Yeah, I am.

I definitely am. We'll just take two of these and come back and see me next week. Well, you're diagnosing me. What was going on? Oh, well, you've got a cold, I think. But let's say you're in the office, I think we should make this as real as possible. I was, let's say that I'm hanging out with my sweet little four-year-old niece who herself has a cold.

Oh, is she the person? I don't want to name names, but I think it's entirely possible that she's on your list now. So, all right, so your little niece probably sneezed or something, or just put her dirty little hands all over your face because she loves Uncle Josh. She has, her dad would not allow her to have dirty hands. Okay. I think she's probably coughing around me.

Okay. Yeah. And what you probably did was inhaled a virus particle, and that probably attached to the linings of your nasal passages and your sinuses. Because apparently there's basically only three ways that a virus gets into your body. You inhale it, it attaches to your mucous membranes like your nose or your gums or something, or it enters through a break in the skin. That's right.

So your host cell is going to break open, your virus is going to move in there with, and say, I'm going to use your equipment like we talked about, then maybe travel to your bloodstream, travel to your lungs, and you're going to end up getting, let's say, maybe one of the first sinuses, a runny nose because you're losing cells in your sinuses and now that fluid is going to be loosened up as a result. Yeah. The nasal, the literal cellular lining of my sinuses is being, is rupturing. It's under attack.

Because here's the thing, when you go through and look at like what a virus does, you're looking at what one individual virion is doing. You don't necessarily just pick up one individual virion. You can be exposed to many, many, many virions, and they are each reproducing, producing thousands more just in one cell. So all this is going on, it can have a pronounced effect. Like if you just lost one cell in your nasal lining, it's not going to do much. You're probably never, ever going to notice.

But if you lose a ton of the cells at the same time, you're going to have a runny nose. Or if it happens in your throat, you're going to have a sore throat. That's right. That's just fluid. It's attacking those cells in your throat and the lining, and it's dripping and just causing like usually some sort of inflammation. Yeah. And because those ruptured cells are being carried down by your nose juice to the back

of your throat, which in turn, it's what I was raised on, mucus, which in turn, nose juice, which in turn, they attach and attack to the cells lining your throat. And then this whole thing is just going on and on and on again. Yeah, if you've ever had aches and pains because of maybe a flu, that's because your muscle cells are being attacked. And it sucks because you don't know that this is going on at first. Like it's just this war being waged inside your body and you're like, you know, hey, I'm just going to the grocery store and I'm feeling pretty good.

Exactly. And by the time you start to feel it's too late. It is too late. I'm glad you brought that up because I did a don't be dumb on when you're actually contagious. Yeah, what's the final on that? So it depends on does it vary the how long your contagious varies. But when you start is about a day before you start showing symptoms. Okay.

So like remember how I said, if you have one cell burst and you're not going to notice it, it's going to take many, many cells to burst before you finally have a sore throat. Well, while those things are bursting after that first one bursts, you're contagious, buddy. So the day before you even know you're sick, you're walking around infecting other people. Right. With a cold, you go from the day before symptoms to about four days after. All right.

And with the flu, you go from the day before symptoms to five to seven days after. Gotcha. So you can still be, it is true when people are like, I'm not contagious anymore. They're usually probably totally wrong. But say they're flu less eight days, they say that on day eight, they're, they're actually right. That makes sense. Most people say it by like day three or four or whatever.

That's, that's all right. Well, they need to watch Don't Be Dumb, Josh's award-winning web series. So many awards, man. I think the next award it's going to win is the most divisive web series. Yeah. Because half the people, well, more than half a thinker are like, man, this is the best thing ever. And people are like, I don't get it.

Why is Josh acting so weird? Yeah. And I'll just respond with, yeah, you don't get it. Yeah. And I mean, it's definitely not for everybody I've learned. Well, it's very funny, I think. Uh, sure. So, all right.

And we mentioned fever. We're going to talk about what that is actually doing inside your body right after this break. I'm Mangesh Atikala and to be honest, I don't believe in astrology, but from the moment I was born, it's been a part of my life in India. It's like smoking. You might not smoke, but you're going to get secondhand astrology. And lately I've been wondering if the universe has been trying to tell me to stop running and pay attention, because maybe there is magic in the stars if you're willing to look

for it. So I rounded up some friends and we dove in and let me tell you, it got weird fast. Tantric curses, Major League Baseball teams, canceled marriages, K-pop. But just when I thought I had to handle on this sweet and curious show about astrology, my whole world came crashing down. The situation doesn't look good, there is risk to father. And my whole view on astrology, it changed. Whether you're a skeptic or a believer, I think your ideas are going to change too.

Listen to Skyline Drive and the iHeart Radio app, Apple Podcast, or wherever you get your podcasts. On the podcast, Hey Dude, the 90s called David Lasher and Christine Taylor, stars of the cult classic show, Hey Dude, bring you back to the days of slip dresses and choker necklaces. We're going to use Hey Dude as our jumping off point, but we are going to unpack and dive back into the decade of the 90s. We lived it and now we're calling on all of our friends to come back and relive it. It's a podcast packed with interviews, co-stars, friends, and non-stop references to the best

decade ever. Do you remember going to Blockbuster? Do you remember Nintendo 64? Do you remember getting frosted tips? Is that a cereal? No, it was hair. Do you remember AOL Instant Messenger and the dial-up sound like poltergeist? So leave a code on your best friend's beeper, because you'll want to be there when the nostalgia

starts flowing. Each episode will rival the feeling of taking out the cartridge from your Game Boy, blowing on it and popping it back in as we take you back to the 90s. Listen to Hey Dude, the 90s called on the iHeart Radio app, Apple Podcasts, or wherever you get your podcasts. So Chuck, it turns out you asked me if I feel feverish and I don't. Apparently my body's slacking on the immune response. Well, I think you don't always get the fever, but fever is a good thing because your body

is wired to operate optimally at 98.6 even though I heard that was 98.7 now. Is that right? Yeah, I heard that they've kind of abandoned that as like an average body temperature because it varies enough between human beings that they're like, now it's this between this. Right. Rather than 98.6 and if you don't have that, you're sick. So somewhere in that range, let's say, chemical reactions and basically anything going on your body, just that's the temperature it likes.

So when you get a fever, it's actually slowing all those processes down, including the viruses spread. Yeah. Because it's like, oh man, it's hot. I can't work as much. That's right. Which is kind of a weird indirect roundabout way of slowing a fever down or slowing an infection down.

Yeah. I mean, I guess if it works. So it's good to have a fever. It is good to have a fever and it actually makes sense in a strange way because some infections, some viruses attack the very cells that are meant to mount the immune response. Like remember Ebola? Yeah. It goes right after like every immune response cell it can find.

HIV goes after T cells, which attack and destroy foreign bodies. So to slow them down and to slow the spread so that the immune response can continue and mount a full attack is kind of clever. Yeah. And since you mentioned HIV, it's another scary one because it's one of those viruses that can just lay and wait. And they even call it sleeping at some times. Yeah.

Like it's not obvious. You know, HIV and be spreading HIV without ever feeling any kind of sick or any kind of symptoms. And basically eventually that virus is going to do its thing. You know, it could lay and wait for years even without acting. Right. And it depends on the virus, but they figure that there's some sort of environmental trigger. One I saw was like exposure to UV blight or something like that.

Oh really? I think herpes is a virus like that. Yeah. It sleeps, which is why people who have like say herpes simplex don't always have cold sores. Yeah. It'll just flare up. Right.

It will flare up. And they often say like in times of stress or something like that. Well, the virus isn't like, oh, this person's stressed out, let's go. There's probably cortisol triggers the virus to start reproducing. But one of the one of the devious aspects of this is when that when that virus sneaks in and inserts its DNA or RNA into the DNA of the cell and just hangs back and waits. Well that cell is dividing as like normal again and again spreading the virus unwittingly right without the virus even being reproduced now set up to be reproduced rather than in

just one cell now four or eight or 16 or 32. And then all hell breaks loose when all of them start going at the same time because they were all exposed to cortisol. Wow. That's what I'm saying. Viruses are amazingly interesting. And wicked, wicked, wicked things. They are.

So here's some tips. The way on, you know, if your office is sick or you're around your four-year-old niece, here's some tips from your buddies here to keep you from getting sick. You know that there are carrier organisms like mosquitoes and fleas. They can spread viruses. We know it can be airborne. We already talked about bodily fluids, whether that's nose juice or saliva or blood or semen or vaginal secretions as one way you can get a direct transfer.

Surfaces on which bodily fluids have dried, which is kind of scary to think about. Yeah. You know. You want to keep all those secretions like off of surfaces because the virus can live outside of the body for a while. Apparently flu virus can live for seven days just on the surface. Yeah. That's why, like, you sneeze into your hand and you open the door to your office, then

there could be a little virus on that doorknob. And that's why they supervise. And one of the things that we're advising now is to wash your hands a lot if you're sick or if you know that there's sickness around you. Right. Like, I wouldn't be in Howard Hughes about it, but I wash my hands a lot when I know that there's viruses going around. I started washing my hands a lot more once I found out or was told what you're actually

doing when you're washing your hand. You're not actually killing anything on your hands, any germs, what you're doing by introducing soap is you're creating something that will basically go and cling to germs on your hands. And then when you wash off the soap, you're washing off the germs. So you're not, like, waging war or anything like that. You're basically just rinsing your hands clean, literally. So once I realized that, I was like, oh, yeah, washing hands makes a lot of sense. Because before that, I was like, soap doesn't do anything.

Really? Yeah. And I don't even use antibacterial soap as a rule, but so I was like, it's definitely not doing anything. Now I'm like, it is doing something. So let's wash our hands as often as possible. That's a good idea. And a really long t-shirt.

If you are sick, you're going to want to cover your mouth when you sneeze and cough because that's just common decency. You want to avoid contact with anyone else's bodily fluids, whether you're sick or not, and whether they're sick or not. It's just you don't want to have anyone else's bodily fluids on your in you unless you know you're like married or something, unless you really love that person. Then fluids are welcome. And antibiotics.

Man, this thing's gotten blue a few times. It's a very sexy show. Yeah. A sexy virus. Antibiotics aren't going to help with a viral infection. That is obviously for bacterial infections only. Yes, but it occurred to me, Chuck, that if you could cure a viral infection in a bacterium, in a bacteria with antibiotics, it'd be kind of like euthanasia, but it would cure the

viral infection. That's a good point. A bacteria infected with the virus. That's how tough viruses are. And we have no idea how they originated or where they came from. We don't. That's true. We just know they're super old.

And the ones that are the oldest are the ones that kill the least. Oh, really? Yeah, if you think about it, a virus would, just by right of natural selection, evolve to be able to reproduce without killing the host. Because if the host survives, then that just increases the chances of the virus to be spread from host to host. So a really deadly virus is probably newer as far as humanity's concerned. And a virus that can infect more organisms, more types of organisms, like one that could

make grass sick, but also make a human sick, that's probably a pretty old virus. Yeah. Old virus just sounds intimidating. Well, we have basically what amounts to fossilized viruses in our DNA from all those viruses, those retroviruses that came in, inserted as genetic material, and our body learned to mount a defense against them. But that stuff is still in the human genome. Crazy.

Viruses. They're also immunizations, of course, and how they work. They pre-infect your body so it knows how to mount the fight against it to make sure it has all the right equipment. It's like putting up wanted posters in your body. Yeah, but those viruses change ever so slightly enough to where you have to keep updating these vaccines so it keeps working. Yeah.

Yeah. They evolve fairly quickly. Lastly, Chuck, I want to address something, there is a, I guess, a misconception or urban legend or whatever that you can tell where you have a viral infection or a bacterial infection or what kind of virus you have based on the color of your mucus. We talked about your narci or fluorescent or something like that. They don't in and of themselves relate to a specific type of virus or bacterial or viral infection or anything like that, it's not true.

So that's viruses. Yeah, I got nothing else. It is good to know how this stuff works though because when you get sick, you understand it a little better. Maybe you can mentally fight this stuff more effectively. I'm doing it right now. Yeah. Do you see how I'm bleeding from my scalp?

Oh my God. I'm using a lot of mental power. It's amazing. If you want to know more about viruses, you can start by typing that word into the search bar at howstuffworks.com and it will bring up this cool article and I said how stuff works. So it's time for listening to me. I'm going to call this Headstones.

My name is Georgia Gilbert. I'm a new but enthusiastic fan from the University of Washington, Bill Huskies. I was listening to your Tombstones podcast and I want to say that the move to church yard burials is a bit more complicated than you implied. If I remember correctly, burials in church yards began mostly as a common practice because of the plague, churches would sell spots for burial within the church itself, in the walls and the floors, et cetera, because there was a common belief during the Middle Ages that being buried in a church was being buried closer to God.

And if you're very closer to God, the better off you're going to be in the afterlife. The reasoning goes. Many people would actually get spots within their local church to be buried or at least very close to the walls outside. During the plague years, however, the amount of bodies accumulated to be buried became too much and they began to bury people further outside the church, even if they had paid for a spot inside. I read a great book on death in London through the ages that talked about it that was called

Necropolis. I highly recommend it. So thanks for teaching me such awesome stuff, guys. I can now ask my mother-in-law intelligent questions about growing up in Germany during the Cold War, thanks to your Berlin Wall program. Nice. And that is from Georgia. That was fascinating.

The plague, by the way, was bacterial, not viral, in case anybody was wondering like me. Yeah, we did one on the plague, right? We did. Yeah. Black death or black plague? Yeah. Anyway, who was that again?

Georgia. Thanks a lot, Georgia. We appreciate that. That was a great email. If you have a great email, you can try to tweet it to us if it's short at SYSK Podcast. You can post it on Facebook if you like at facebook.com slash stuff you should know. Or you can send us an email like a normal person to stuffpodcastathowstuffworks.com. And as always, in the meantime, hang out with us at our home on the web, stuffyoushouldknow.com.

For more on this and thousands of other topics, visit howstuffworks.com. I'm Munga Shatikular and it turns out astrology is way more widespread than any of us want to believe. You can find it in Major League Baseball, international banks, K-pop groups, even the White House. But just when I thought I had a handle on this subject, something completely unbelievable happened to me and my whole view on astrology changed. Whether you're a skeptic or a believer, give me a few minutes because I think your ideas

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