WEBVTT - Ep 18 Hantavirus: The Real Rat Race 0:00:00.760 --> 0:00:03.880 She began to feel feverish and achy, and believed she 0:00:03.960 --> 0:00:07.480 had the flu. When the aches and pains grew more severe, 0:00:08.000 --> 0:00:11.480 she sought medical attention and was hospitalized before the respiratory 0:00:11.520 --> 0:00:15.920 symptoms appeared. She speaks of drowning, of perceiving a great 0:00:15.960 --> 0:00:19.440 weight on her chest, and a great exhaustion. She speaks 0:00:19.440 --> 0:00:22.280 of wanting to see her children one last time, and 0:00:22.320 --> 0:00:25.880 then of her mixed emotions about being sedated. I wanted 0:00:25.920 --> 0:00:28.760 to live, she said, of course I did. I didn't 0:00:28.760 --> 0:00:30.680 want to leave my family. They needed me. 0:00:31.120 --> 0:00:34.960 But I was just so tired. I was just so tired. 0:00:36.040 --> 0:00:39.240 She did survive, and sometimes she says she still grows 0:00:39.280 --> 0:00:42.560 so weary that she realized she'll never fully recover from 0:00:42.560 --> 0:00:46.360 her encounter with the virus. She says, it's the most 0:00:46.400 --> 0:00:50.240 horrible feeling, the tubes, the liquid in your lungs, the choking. 0:00:51.040 --> 0:00:52.919 You don't want to die that way, but you know 0:00:53.000 --> 0:01:32.200 you can't live that way either. Shoot. Yeah, dang bad one. 0:01:32.319 --> 0:01:34.600 Yeah. 0:01:34.800 --> 0:01:41.520 Every episode, Hello, Hello, I'm Aaron Welsh. 0:01:41.240 --> 0:01:43.240 And I'm Aaron Oman Updyke and. 0:01:43.280 --> 0:01:45.280 This is this podcast will kill you. 0:01:45.760 --> 0:01:47.160 Yeah it's. 0:01:48.480 --> 0:01:52.440 And this week we're talking all about hauntaviruses, and so 0:01:52.560 --> 0:01:56.520 what you just heard was an excerpt from the Book 0:01:56.640 --> 0:02:01.120 of Mice, Men and Microbes, which goes in to the 0:02:01.160 --> 0:02:05.920 history of hantaviruses, with particular focus on the Sonombree outbreak, 0:02:05.960 --> 0:02:07.800 which you'll hear a lot more about in a bit. 0:02:08.000 --> 0:02:14.880 Yeah cool, okay, cool. So let's get into our business, and. 0:02:14.880 --> 0:02:21.040 Our business is quarantine quarantinies. What are we drinking this week? 0:02:21.080 --> 0:02:25.720 This week, we're drinking the mouse Trap. It is so good, 0:02:26.240 --> 0:02:31.920 unbelievably delicious. It has, which is arguably the best liquor. 0:02:34.320 --> 0:02:36.679 I'm not even gonna I'm that's I'm immediately cutting that. 0:02:43.840 --> 0:02:45.880 It could be, it could be argued, but I think 0:02:45.919 --> 0:02:47.560 I have a different one in mine. Anyway. 0:02:48.440 --> 0:02:54.040 It's also got rosemary, simple syrup, blood orange juice, lime juice, 0:02:54.480 --> 0:02:58.079 and a splash of soda water. So we will post 0:02:58.280 --> 0:03:02.440 the recipe for this quarantiny the mouse Trap, as well 0:03:02.480 --> 0:03:05.359 as the Place Barrita on all of our social media. 0:03:05.200 --> 0:03:08.680 Which is our non alcoholic version of our quarantine. You'll 0:03:08.720 --> 0:03:11.200 be able to find the full recipes on our website 0:03:11.240 --> 0:03:14.840 as well as this podcast Will Kill You on Facebook 0:03:14.880 --> 0:03:18.400 and Instagram and TPWKY on Twitter. 0:03:19.440 --> 0:03:23.520 Okay, so I'm very excited for this episode. And I 0:03:23.600 --> 0:03:26.200 know that I say that every episode, and I genuinely 0:03:26.240 --> 0:03:28.080 mean it every episode, because. 0:03:27.840 --> 0:03:30.560 Every episode is exciting. It's something new, and we learn 0:03:30.680 --> 0:03:33.080 stuff while we're researching it, and then we get to 0:03:33.160 --> 0:03:35.760 learn more stuff as we listen to each other teach 0:03:35.840 --> 0:03:37.240 us the things that we didn't know. 0:03:38.000 --> 0:03:40.600 Let's get started. Tell me about the biology. 0:03:40.080 --> 0:04:11.200 Er Okay, I'd love to. Hantavirus is aka ortho hantaviruses. 0:04:12.080 --> 0:04:16.360 This is a group of viruses. They are single stranded, 0:04:16.600 --> 0:04:20.359 they're in an envelope, and they're an RNA virus. You 0:04:20.480 --> 0:04:21.080 just learned so. 0:04:21.120 --> 0:04:26.880 Much, okay, and what is the ortho part of all that? 0:04:27.000 --> 0:04:29.640 I don't know why they changed the name from hantaviruses 0:04:29.720 --> 0:04:33.599 to ortho hantaviruses at some point recently. The phylogeny of 0:04:33.600 --> 0:04:36.359 this is confusing to me. Sometimes they call it the 0:04:36.520 --> 0:04:40.880 order bunia Viralis. Sometimes they call that the family Bunyaviridae. 0:04:41.920 --> 0:04:45.279 Who knows. If you see the word bunia virus, that 0:04:45.520 --> 0:04:49.119 is a larger group of viruses that includes the hauntaviruses. 0:04:49.640 --> 0:04:53.000 It also includes a lot of other viruses which cause 0:04:53.320 --> 0:04:58.960 horrible diseases including crime and congo hemorrhagic fever, rift valley 0:04:59.000 --> 0:05:04.240 fav several different encephalitis viruses, and so many more. 0:05:05.040 --> 0:05:06.440 So this is a pretty. 0:05:08.240 --> 0:05:10.279 Gnarly family group. 0:05:10.440 --> 0:05:14.640 It's a gnarly group order of viruses. It's a gnarly 0:05:14.680 --> 0:05:19.080 group of viruses that love to infect humans, which not 0:05:19.160 --> 0:05:22.120 all virus groups love to do that these ones do. 0:05:22.960 --> 0:05:27.240 What's interesting about hantaviruses specifically in this family or order 0:05:27.440 --> 0:05:30.680 or whatever is that they're the only ones, for the 0:05:30.720 --> 0:05:33.919 most part, that aren't transmitted by ticks and mosquitoes. So 0:05:34.080 --> 0:05:37.240 most of the other viruses in this Bunya Veridae or 0:05:37.279 --> 0:05:45.240 buniavialis group are transmitted by ticks or mosquitoes, not hantaviruses, right, 0:05:47.040 --> 0:05:54.960 So hantaviruses, in contrast, are transmitted through rodent excrement yummies. 0:05:55.120 --> 0:05:58.960 So fun. What I love is that so arthropod born 0:05:59.160 --> 0:06:02.400 viruses that are transmitted by ticks and mosquitoes are often 0:06:02.440 --> 0:06:09.560 called arboviruses. You could call these roboviruses rodent born. I 0:06:09.600 --> 0:06:13.640 love it anyways, very very sci fi. It's very sci fi. 0:06:14.640 --> 0:06:20.240 So hontaviruses are transmitted by rodent excrement. What does that mean. 0:06:20.520 --> 0:06:24.720 It means that these viruses live their life cycle inside 0:06:24.760 --> 0:06:28.440 of rodents, and they're naturally found in rodent populations honestly 0:06:28.480 --> 0:06:32.560 across the globe. Various different hantaviruses are found in almost 0:06:32.600 --> 0:06:39.240 every continent, in different rodent species, and they circulate in 0:06:39.279 --> 0:06:42.360 these rodent populations really without causing a lot of damage. 0:06:42.400 --> 0:06:47.159 They don't harm the rodent populations. Really, They kind of 0:06:47.240 --> 0:06:48.920 do okay. 0:06:50.200 --> 0:06:51.440 Overwintering survival. 0:06:51.760 --> 0:06:54.720 Okay, so that counts. But they don't cause the kind 0:06:54.760 --> 0:06:57.440 of damage that they cause in humans in general, in 0:06:57.480 --> 0:07:01.760 the rodent populations, which suggests that they have sort of 0:07:01.760 --> 0:07:05.000 a history like these are the groups of animals that 0:07:05.040 --> 0:07:09.039 they are sort of evolved to infect, if that makes sense. 0:07:10.080 --> 0:07:14.160 So in humans hantaviruses, of which there are a number, 0:07:14.200 --> 0:07:16.440 and I'll tell you the names of a bunch of them, 0:07:16.720 --> 0:07:23.640 they cause two major diseases, sort of two distinct groups 0:07:23.680 --> 0:07:27.040 of illnesses. The first that you might have heard of 0:07:27.560 --> 0:07:31.960 is called hantavirus pulmonary syndrome. You've heard of that aaron, 0:07:32.760 --> 0:07:37.240 of course, and the other is called hemorrhagic fever with 0:07:37.600 --> 0:07:38.680 renal syndrome. 0:07:39.280 --> 0:07:42.320 That sounds quite bad, right if you had. 0:07:42.160 --> 0:07:44.320 To guess like, which one of that sounds the worst? 0:07:44.640 --> 0:07:47.360 I mean hemorrhagic fever. I would automatically say, oh my. 0:07:47.400 --> 0:07:49.440 Gosh, that sounds terrible. 0:07:49.840 --> 0:07:53.720 Right, But knowing hantaviruses and this leading. 0:07:53.520 --> 0:07:58.640 Question, so yes, it's actually hantavirus pulmonary syndrome that is 0:07:58.680 --> 0:08:02.160 the more severe of the disorders. So what I'm gonna 0:08:02.200 --> 0:08:04.960 do is I'm gonna go through each of these two disorders, 0:08:05.040 --> 0:08:11.000 hantavirus pulmonary syndrome and hemorrhagic fever with renal syndrome, talk 0:08:11.000 --> 0:08:14.720 about what's different about them, and then talk about what's 0:08:14.960 --> 0:08:20.360 similar about them. Sounds good, cool, sounds great. So hauntavirus 0:08:20.680 --> 0:08:23.679 pulmonary syndrome, We'll start with that because it's my personal favorite, 0:08:24.040 --> 0:08:26.880 and it's the one that's the one that people are 0:08:27.000 --> 0:08:29.480 probably more familiar with if you live in the United States, 0:08:29.520 --> 0:08:34.920 because this is caused primarily by sindombree virus, and this 0:08:35.040 --> 0:08:38.679 is the hauntavirus that exists in the United States in 0:08:38.720 --> 0:08:43.560 the Southwest. It's hosted or its its reservoir host is 0:08:43.559 --> 0:08:44.320 the deer mouse. 0:08:44.920 --> 0:08:46.800 I like the term hosted. 0:08:47.000 --> 0:08:55.679 Actually it's hosted by the lovely deer mouse, and it 0:08:55.760 --> 0:08:58.959 causes a disease that has a death rate of thirty 0:08:59.200 --> 0:09:01.160 eight to fifty percent. 0:09:02.080 --> 0:09:03.320 That's enormous. 0:09:03.400 --> 0:09:08.480 It's enormous. It's a very very scary illness. So here's 0:09:08.480 --> 0:09:15.000 how it happens. There's four different phases of HPS hauntavirus 0:09:15.000 --> 0:09:19.320 pulmonary syndrome. Okay, it starts after an incubation period of 0:09:19.400 --> 0:09:22.680 between nine and twenty four days, usually about one to 0:09:22.760 --> 0:09:26.040 five weeks, which is a pretty wide incubation period. And 0:09:26.080 --> 0:09:28.760 that's again the time from when you're infected to the 0:09:28.760 --> 0:09:32.680 time when you first show symptoms. And so after that 0:09:32.760 --> 0:09:38.319 incubation period, the first phase is the febrile phase. Febrile 0:09:38.440 --> 0:09:41.320 means fever, so as you can guess, this starts with 0:09:41.440 --> 0:09:46.120 a fever. You'll also have muscle aches and malaise. You'll 0:09:46.120 --> 0:09:50.440 probably have a headache, some dizziness kind of like you 0:09:50.520 --> 0:09:53.040 have the flu. You might even have some nausea or 0:09:53.120 --> 0:09:56.280 abdominal pain. But what's important is that you don't have 0:09:56.400 --> 0:09:59.040 upper respiratory symptoms like you would with the cold or 0:09:59.040 --> 0:10:01.920 the flu, So no stuff, no sore throat things like that. 0:10:02.760 --> 0:10:05.800 You could end up with a cough at the end 0:10:06.000 --> 0:10:09.199 of this phase. Now, this phase, the febrile phase lasts 0:10:09.200 --> 0:10:12.319 between three and five days, but it could last as 0:10:12.320 --> 0:10:13.280 long as twelve. 0:10:14.480 --> 0:10:19.360 So again, is it because are these wide ranging incubation 0:10:19.480 --> 0:10:23.239 times and certain phases because there are just a relatively 0:10:23.920 --> 0:10:27.920 low number of cases that for comparison proper. Is it 0:10:28.040 --> 0:10:32.079 just that the virus really is host like individual dependent. 0:10:32.360 --> 0:10:34.760 I think it's probably a combination of both. So hantavirus 0:10:34.760 --> 0:10:37.280 pulmonary syndrome. We don't there's not There haven't been a 0:10:37.320 --> 0:10:39.240 ton of cases of this, so you're definitely gonna have 0:10:39.280 --> 0:10:41.480 wider variation because of that when you have a small 0:10:41.520 --> 0:10:45.520 sample size. But it's also very likely that your exposure 0:10:45.920 --> 0:10:49.200 will determine how much virus you're exposed to, and then 0:10:49.240 --> 0:10:51.800 that can have a really huge impact on incubation period. 0:10:52.160 --> 0:10:53.040 Right. Yeah. 0:10:53.480 --> 0:10:57.240 Also, I really like that this is just a total 0:10:57.280 --> 0:10:59.800 side note, but it started with a fever. 0:11:00.080 --> 0:11:02.319 Would have also been a great name for this podcast. 0:11:03.320 --> 0:11:04.320 It would have been. 0:11:04.360 --> 0:11:11.439 Oh shit, oh god, that's a good name. That's future podcast, 0:11:11.760 --> 0:11:16.200 Future podcast. And the bummer about this first phase is 0:11:16.200 --> 0:11:19.520 that it's super hard to diagnose because your symptoms are 0:11:19.720 --> 0:11:23.880 very nondescript, and you're about to see that after this phase, 0:11:23.960 --> 0:11:28.280 it gets bad really quick. So phase two is the 0:11:28.320 --> 0:11:32.160 cardiopulmonary phase. This is the beefy part of the disease, 0:11:32.600 --> 0:11:36.440 and it happens really fast. Within twenty four to forty 0:11:36.480 --> 0:11:40.200 eight hours after these symptoms start, up to fifty percent 0:11:40.600 --> 0:11:45.880 of infected people will die. Ooh yeah. So basically you 0:11:45.960 --> 0:11:49.680 present with shock and pulmonary edema. So let's talk about these. 0:11:50.960 --> 0:11:55.120 We've talked about shock before. Shock is what happens when 0:11:55.280 --> 0:11:58.559 for some reason, your blood pressure is going to drop 0:11:58.960 --> 0:12:02.520 and you're not going to get blood profusion to your tissues, 0:12:02.679 --> 0:12:04.840 so your organs are going to start to die because 0:12:04.880 --> 0:12:10.040 they don't have adequate blood flow. In this case, the 0:12:10.120 --> 0:12:13.160 symptoms that happen are in large part due to what's 0:12:13.200 --> 0:12:17.800 called vascular permeability, which means your blood vessels become leaky, 0:12:17.960 --> 0:12:21.680 especially the blood vessels in your lungs. So the fluid 0:12:21.679 --> 0:12:24.400 that's supposed to be in your blood vessels, aka your blood, 0:12:24.760 --> 0:12:28.320 starts leaking out into the space between your cells in 0:12:28.360 --> 0:12:32.280 your lungs, and that results in what's called pulmonary edema, 0:12:32.440 --> 0:12:35.240 which means fluid on your lungs. 0:12:35.840 --> 0:12:38.280 Oh so I knew that that's what that meant, but 0:12:38.360 --> 0:12:41.199 I didn't know how that happened. Yeah, that's very interesting. 0:12:41.320 --> 0:12:43.679 That's how it happens in this case. Pulmonary deal can 0:12:43.720 --> 0:12:46.160 happen other ways as well. Yeah, oh, I want to 0:12:46.200 --> 0:12:49.360 know all the ways. I'm sure we'll have so many 0:12:49.400 --> 0:12:53.480 diseases to talk about. Various forms of pulmonary edema. But 0:12:53.640 --> 0:12:58.880 it's often from fluid leaking out from your your blood vessels. 0:12:59.080 --> 0:13:01.600 It's not always straight up blood like in this case. 0:13:01.640 --> 0:13:04.480 It's often whole blood that's able to get through. Sometimes 0:13:04.480 --> 0:13:08.080 it's just plasma or just like the fluid and not 0:13:08.240 --> 0:13:10.760 like your entire like red blood cells and stuff. It 0:13:10.840 --> 0:13:14.800 just depends on how big the holes that are allowing 0:13:14.880 --> 0:13:16.240 the leakage are. If that kind of. 0:13:16.240 --> 0:13:19.120 Makes that's so interesting, it's very cool. 0:13:19.720 --> 0:13:22.679 You can imagine that all of this edema makes it 0:13:22.880 --> 0:13:27.160 really hard to breathe. It also because your heart is 0:13:27.200 --> 0:13:29.480 sort of right in between your lungs, makes it hard 0:13:29.480 --> 0:13:32.000 for your heart to beat, and so that's why you 0:13:32.080 --> 0:13:35.280 end up going into cardiogenic shock, which means your heart 0:13:35.640 --> 0:13:37.600 The reason that you go into shock is because your 0:13:37.640 --> 0:13:40.080 heart is not pumping enough blood out. 0:13:40.520 --> 0:13:43.360 And that's only because it's restricted in space by your 0:13:43.440 --> 0:13:46.040 lungs filling up with your own fluid slash blood. 0:13:46.280 --> 0:13:48.800 Yeah, and because you're bleeding out into your own body, 0:13:48.840 --> 0:13:50.800 so there's not enough blood getting to your heart, so 0:13:50.840 --> 0:13:51.320 it's a double. 0:13:51.440 --> 0:13:54.600 Your blood pressure is just like exactly totally down. 0:13:55.000 --> 0:13:58.320 Yeah, yeah, cool, right, So. 0:13:58.559 --> 0:13:59.959 This result is horrifying. 0:14:00.080 --> 0:14:03.800 It's very horrifying. There's because of this, because of all 0:14:03.840 --> 0:14:06.839 the blood that you're leaking out, your blood is then 0:14:07.200 --> 0:14:10.439 not making it to your other organs, so your kidneys 0:14:10.559 --> 0:14:13.360 will likely start to fail, so you might end up 0:14:13.360 --> 0:14:18.720 with what's called aliguria, which means low urine, few urine, 0:14:18.920 --> 0:14:22.680 it's not good. And yeah, so that basically fifty percent 0:14:22.720 --> 0:14:26.760 of people are going to die. However, the other fifty 0:14:26.800 --> 0:14:28.840 percent or sometimes more, it could be as low as 0:14:28.960 --> 0:14:31.840 thirty percent of people who die, So fifty to seventy 0:14:31.840 --> 0:14:36.360 percent of people will then somehow progress to the diuretic phase, 0:14:36.400 --> 0:14:40.320 which is phase three of this disease, which is when 0:14:40.600 --> 0:14:45.720 your pulmonary edema clears up, your urine output increases, and 0:14:45.760 --> 0:14:51.600 the fever and shock resolve. Okay, don't ask me exactly 0:14:51.680 --> 0:14:56.360 how that happens. Yeah, I would love to have a 0:14:56.400 --> 0:15:01.560 great answer on that. It is unclear to me if 0:15:01.680 --> 0:15:05.560 you're you're an output goes low, that's a very bad sign. 0:15:06.120 --> 0:15:08.360 If you then all of a sudden start peeing out 0:15:08.400 --> 0:15:11.320 a lot, that's actually a good sign because it means 0:15:11.360 --> 0:15:15.359 that something is somehow your body is trying to re equilibrate, 0:15:16.200 --> 0:15:19.520 and then you're entering the diuretic phase. After that, you're 0:15:19.560 --> 0:15:22.160 in what's called the convalescent phase, which can last for 0:15:22.240 --> 0:15:25.160 several months. So this is a very long recovery period 0:15:26.120 --> 0:15:30.760 and often often people recover fully, but it is also 0:15:30.880 --> 0:15:34.440 possible to have long term pulmonary symptoms, like decreased blood 0:15:34.440 --> 0:15:37.200 flow in your lungs because of just how much damage 0:15:37.200 --> 0:15:37.920 has been caused. 0:15:38.920 --> 0:15:44.480 Okay, that's yeah, yeah, and how like the damage in 0:15:44.520 --> 0:15:47.280 your lungs is caused by the like in the blood 0:15:47.360 --> 0:15:49.480 vessels themselves or yeah. 0:15:49.200 --> 0:15:52.320 We'll talk about exactly what causes that, what allows for 0:15:52.360 --> 0:15:54.680 that blood to leak out in just a second, because 0:15:54.720 --> 0:15:58.000 it's it's a really important part of this disease. So 0:15:58.120 --> 0:16:03.360 that's HPS hantavirus pulmonary syndrome. Let's talk about hemorrhagic fever 0:16:03.480 --> 0:16:06.880 with renal syndrome. So this is the other form of 0:16:06.920 --> 0:16:10.560 hantavirus which many people I guess if you live in 0:16:10.600 --> 0:16:13.280 Europe or Asia, this might be what's more familiar to you. 0:16:13.360 --> 0:16:15.000 If you live in the US, you might never have 0:16:15.080 --> 0:16:18.200 heard of this. This is caused by a number of 0:16:18.240 --> 0:16:23.440 different hauntaviruses, including soul virus, which was first discovered in Soul, 0:16:23.520 --> 0:16:27.760 Korea and is hosted by the Norway rat, and the 0:16:27.760 --> 0:16:32.400 black rat. Hatan virus also discovered in Korea, which is 0:16:32.440 --> 0:16:36.760 hosted by the striped field mouse. Uh, pumala is that 0:16:36.800 --> 0:16:40.840 how you say that? Pumala pumala virus which is from 0:16:41.200 --> 0:16:47.600 Finland and hosted by the bank vowl. And do Brava virus, 0:16:48.200 --> 0:16:53.880 do brava do brava, dobrava virus whatever, which one of 0:16:53.960 --> 0:16:57.240 those covered in Slovenia and is hosted by the yellow 0:16:57.240 --> 0:17:00.960 necked field mouse. Oh, that's a lot of viruses. So 0:17:01.840 --> 0:17:06.679 all of these viruses, which are different haunted viruses, cause 0:17:07.080 --> 0:17:11.840 various forms of HFRS hemorrhagic fever with renal syndrome. 0:17:12.280 --> 0:17:14.840 This is so one of the things, just to pause 0:17:14.880 --> 0:17:21.640 that I noticed too many acronyms tell me about it. 0:17:21.640 --> 0:17:26.080 It's ridiculous. It's ridiculous, Okay. So then the hemorrhagic one, So. 0:17:26.040 --> 0:17:29.320 The hemorrhagic one. We've got at least four different viruses 0:17:29.320 --> 0:17:33.159 that we're talking about here, and they cause the same disease, 0:17:33.240 --> 0:17:36.520 but with varying degrees of severity. So, for example, Pumala 0:17:36.560 --> 0:17:40.120 virus in Finland has a very low estimated mortality rate 0:17:40.160 --> 0:17:44.639 between one and three percent, whereas Hatan virus has a 0:17:44.680 --> 0:17:47.440 mortality rate of between five and fifteen percent, so it's 0:17:47.480 --> 0:17:51.320 a much more severe illness. What's interesting is that because 0:17:51.400 --> 0:17:57.480 these viruses cause diseases of varying severity in different countries, 0:17:57.480 --> 0:18:00.879 they have different names for them. So for a while, 0:18:01.440 --> 0:18:05.360 the disease that hunt On virus causes was called KHF 0:18:05.440 --> 0:18:09.639 or Korean hemorrhagic fever. Pumla virus it's often the disease 0:18:09.640 --> 0:18:14.440 it causes is often called nephropathia epidemica. It's absurd, they're 0:18:14.480 --> 0:18:17.520 all the same disease. I'm gonna argue, and hopefully you'll 0:18:17.520 --> 0:18:19.520 agree with me by the end of this episode, that 0:18:19.760 --> 0:18:22.879 all of the diseases caused by hauntavirus should be called 0:18:23.160 --> 0:18:26.080 the same thing. I'm not alone. I have an article 0:18:26.119 --> 0:18:30.880 to site for it, so let's get into it. HFRS 0:18:31.520 --> 0:18:34.800 it has five stages, not just four like we saw 0:18:34.800 --> 0:18:40.439 with HPS, and it starts similarly first phase febrile fever, 0:18:40.720 --> 0:18:45.119 muscle aches, headache, nausea. You also might get flushing of 0:18:45.119 --> 0:18:47.760 your face, and that's because again we know there's going 0:18:47.800 --> 0:18:50.800 to be vascular involvement, and so anytime your your blood 0:18:50.840 --> 0:18:53.960 vessels are dilating, you might get flushing of your face 0:18:54.000 --> 0:18:58.600 because you've got blood flow there. That makes sense, Yeah, 0:18:58.680 --> 0:19:03.120 And you'll move more quickly into the second phase, which 0:19:03.160 --> 0:19:07.320 is the hypotensive phase. So this is again where your 0:19:07.320 --> 0:19:12.639 blood pressure drops. You'll also likely have what's called thrombocytopenia, 0:19:12.720 --> 0:19:15.000 which you also do see in HPS, and it just 0:19:15.040 --> 0:19:19.120 means that you have a low platelet count. A low 0:19:19.200 --> 0:19:22.080 platelet count is bad because it means you're likely to 0:19:22.200 --> 0:19:26.280 bleed out. So platelets are what's responsible for clotting. So 0:19:26.359 --> 0:19:30.200 without platelets, you are at a higher risk of bleeding. 0:19:31.359 --> 0:19:35.040 So then because of the thrombocidopenia, you might have certain 0:19:35.440 --> 0:19:40.159 skin bleeding manifestations little red purple dots, which basically are 0:19:40.200 --> 0:19:43.800 small hemorrhages happening under your skin. And then you'll move 0:19:43.960 --> 0:19:47.359 into the oliguric phase, which though we didn't have a 0:19:47.400 --> 0:19:51.479 phase called oliguria in HPS, we did see that you 0:19:51.560 --> 0:19:54.680 also have a drop in your an output. The biggest 0:19:54.680 --> 0:20:02.000 difference here is that the effects of h FRS tend 0:20:02.119 --> 0:20:06.840 to happen mostly in the kidneys instead of in the lungs. 0:20:08.160 --> 0:20:11.720 So we see your kidneys starting to fail first rather 0:20:11.800 --> 0:20:14.520 than your lungs filling up with fluid. So you're not 0:20:14.560 --> 0:20:16.960 gonna have a cough, You're not going to have the 0:20:17.000 --> 0:20:19.800 pulmonary edema. Does that make sense? 0:20:19.800 --> 0:20:22.359 Why? Why are they different? Or is that am I 0:20:22.440 --> 0:20:23.120 jumping the gun? 0:20:23.200 --> 0:20:25.520 You're jumping the gun a little bit. Let's finish out 0:20:25.560 --> 0:20:30.520 this HFRS. Once you see that decrease in you're an output, 0:20:31.240 --> 0:20:35.080 it's bad news. But again, HFRS overall has a much 0:20:35.119 --> 0:20:38.040 lower mortality rate. So most people are going to start 0:20:38.040 --> 0:20:41.680 to recover, and then they'll enter the polyuric phase, which 0:20:41.720 --> 0:20:45.040 means a lot of p they'll start to diaryse and 0:20:45.200 --> 0:20:48.800 pee a whole bunch out, uh, and then convalesce. 0:20:50.600 --> 0:20:50.879 Cool. 0:20:52.040 --> 0:20:57.120 Cool, So the question is not cool, It's terrible. Not cool. 0:20:58.680 --> 0:21:02.639 But here's the thing what I think is really important 0:21:03.480 --> 0:21:07.840 and what makes these diseases really really cool, and also 0:21:07.920 --> 0:21:13.520 why pathophysiology is my favorite subject. Right now is that 0:21:13.600 --> 0:21:17.520 even though these sound like okay, HPS, you're going to 0:21:17.560 --> 0:21:19.760 have fluid all over your heart and lungs and you're 0:21:19.760 --> 0:21:21.680 going to die because you can't breathe and your heart 0:21:21.680 --> 0:21:25.800 can't beat HFRS. Your kidneys are going to shut down, 0:21:25.920 --> 0:21:28.480 and maybe you'll be able to recover, and maybe you won't. 0:21:28.760 --> 0:21:36.439 These two seem like very different diseases, but they're not. 0:21:37.800 --> 0:21:42.040 They're so closely related, and if you understand what's happening 0:21:42.160 --> 0:21:45.919 inside of your cells, it's the exact same thing. So 0:21:46.000 --> 0:21:52.719 here's what happens. Hantaviruses infect your endothelial cells. These are 0:21:52.760 --> 0:21:57.520 the cells that line your blood vessels. Okay, they get 0:21:57.560 --> 0:22:01.919 into those endothelial cells, they replicate, and they cause damage. 0:22:02.040 --> 0:22:05.359 They don't necessarily kill the cells themselves, but they cause 0:22:05.480 --> 0:22:09.439 enough damage that other cells come in and things like 0:22:09.560 --> 0:22:15.879 histamine are released, which causes vasodilation and increased vascular permeability. 0:22:15.920 --> 0:22:19.320 This means that your blood vessels are now leaky, so 0:22:19.400 --> 0:22:24.119 you have fluid loss and blood loss and hypotension. This 0:22:24.320 --> 0:22:28.400 is the exact same mechanism that happens in HPS and 0:22:28.440 --> 0:22:34.840 in HFRS. The only difference is what tissue is the 0:22:34.920 --> 0:22:40.679 hantavirus primarily infecting the endothelial cells of your lungs or 0:22:40.680 --> 0:22:42.840 the endothelial cells of your kidneys. 0:22:43.520 --> 0:22:46.840 And why is there a difference, Like, why is there 0:22:46.840 --> 0:22:48.520 a differential preference? 0:22:48.840 --> 0:22:51.880 Right that no idea? 0:22:52.040 --> 0:22:56.399 Huh yeah? Interesting, right? Is it really sort of this 0:22:56.520 --> 0:23:01.240 old world new world situation in terms of pulmon versus renal? 0:23:01.800 --> 0:23:04.240 Yeah, so the ones in South America do tend to 0:23:04.280 --> 0:23:08.840 cause more HPS like symptoms, at least from what I read. Okay, 0:23:10.040 --> 0:23:16.040 so yeah, it's just it's so interesting, hmm. But yeah, 0:23:16.080 --> 0:23:18.520 they are transmitted in exactly the same way. So they're 0:23:18.520 --> 0:23:22.479 transmitted in the excrement of rodents. So basically you have 0:23:22.520 --> 0:23:26.560 to aerosolize pee or poop from a rat or a 0:23:26.560 --> 0:23:31.639 mouse or a vole that's infected and inhale it. But 0:23:31.680 --> 0:23:33.760 what I think is so cool is that you have 0:23:33.880 --> 0:23:38.160 these two diseases which on their face seem so different, 0:23:38.160 --> 0:23:41.800 and yet the underlying mechanism that causes the disease is 0:23:41.880 --> 0:23:42.879 exactly the same. 0:23:43.680 --> 0:23:46.320 Yeah, that's super interesting. 0:23:48.320 --> 0:23:52.639 Oh, I should say very importantly, for the most part, 0:23:53.119 --> 0:23:56.439 the disease cannot be transmitted person to person. There's like 0:23:56.840 --> 0:24:01.720 one case where it possibly a huntavirus. Andy's virus in 0:24:01.760 --> 0:24:05.840 South America was possibly transmitted person to person, but every 0:24:05.880 --> 0:24:09.720 other hauntavirus in as many studies as they've tried, has 0:24:09.840 --> 0:24:12.240 never been shown to be able to be transmitted from 0:24:12.280 --> 0:24:18.720 person to person. It's exclusively from aerosolized rodent excrement. So, Aaron, 0:24:19.320 --> 0:24:22.359 tell me about this. How did we get here? How 0:24:22.400 --> 0:24:23.280 did this all start? 0:24:24.160 --> 0:24:52.680 Okay? I think I can answer that. When we picked 0:24:52.720 --> 0:24:56.440 hantaviruses to cover this season, I don't think either of 0:24:56.520 --> 0:25:00.320 us realized just how large the world of hantaviruses it is, 0:25:00.960 --> 0:25:05.840 and also how much the story is still developing. Okay, 0:25:05.920 --> 0:25:08.200 but before we get to where we are today, let's 0:25:08.400 --> 0:25:10.960 as always go back to where we started, or at 0:25:11.040 --> 0:25:15.119 least where the virus started. Hantaviruses have been around for 0:25:15.240 --> 0:25:18.280 millions of years. They can be found in rodents on 0:25:18.359 --> 0:25:23.800 every continent except for Antarctica, and their diversity is astounding. 0:25:24.720 --> 0:25:27.000 But when did humans start to get involved? 0:25:27.320 --> 0:25:27.560 Yeah? 0:25:27.840 --> 0:25:31.680 As early humans began to farm and form stationary settlements 0:25:31.720 --> 0:25:36.119 and store food, which is a key factor, many rodent 0:25:36.160 --> 0:25:39.040 species settled with them, and the easy access to food 0:25:39.040 --> 0:25:43.879 and shelter promoted this close relationship. Because of this, humans 0:25:43.880 --> 0:25:48.520 have probably been exposed to or infected with hantaviruses for millennia, 0:25:49.880 --> 0:25:54.399 but it's not until really, like a long time ago, 0:25:54.920 --> 0:25:57.280 nine hundred and sixty a D. I'm like, oh, but 0:25:57.320 --> 0:26:02.840 it's not until that time, right, So nine hundred and 0:26:02.880 --> 0:26:05.720 sixty a D. Thousand years ago that we get our 0:26:06.040 --> 0:26:10.320 first bit of evidence for this, a Chinese medical account 0:26:10.320 --> 0:26:13.600 of a disease that sounds a whole lot like heemorrhagic 0:26:13.640 --> 0:26:17.960 fever with renal syndrome. But then it more or less 0:26:17.960 --> 0:26:22.320 disappears from medical textbooks for almost a thousand years. Although 0:26:22.960 --> 0:26:27.360 side note, some people believe that the mysterious sweating sickness 0:26:27.359 --> 0:26:31.000 that plagued England and continental Europe during the fifteenth and 0:26:31.040 --> 0:26:34.520 sixteenth centuries might have been caused by a haunt of virus. 0:26:34.760 --> 0:26:39.680 Really yeah, so apparently the symptoms were fairly similar. There 0:26:39.800 --> 0:26:43.440 was this seasonal pattern and in these irregular intervals. Oh, 0:26:44.680 --> 0:26:46.440 but it's still. 0:26:46.320 --> 0:26:47.520 Far from conclusive. 0:26:47.680 --> 0:26:49.919 So, for one thing, this sweating sickness seemed to be 0:26:50.000 --> 0:26:54.800 transmitted person to person, which is rarely or never seen 0:26:55.040 --> 0:27:00.320 in hantavirus outbreaks. And for another, outbreaks appeared sudden and 0:27:00.359 --> 0:27:04.280 disappeared suddenly without any mention of previous cases or reports 0:27:04.320 --> 0:27:08.680 of rodent population increases. But just in case, we should 0:27:08.680 --> 0:27:11.600