1 00:00:00,120 --> 00:00:03,759 Speaker 1: Welcome everyone to the deep dive Today. We're going to 2 00:00:03,839 --> 00:00:07,240 dive into this world that's well, it's literally all around us, 3 00:00:07,320 --> 00:00:10,960 but almost entirely unseen. Imagine if you can, this war, 4 00:00:11,480 --> 00:00:14,919 a war that's been going on for billions of years, billions. 5 00:00:15,000 --> 00:00:17,000 Speaker 2: Yeah, it's mind boggling. 6 00:00:16,600 --> 00:00:22,440 Speaker 1: A constant kind of brutal struggle for survival, all happening 7 00:00:22,440 --> 00:00:23,640 at the microscopic level. 8 00:00:23,719 --> 00:00:27,559 Speaker 3: Absolutely a universe packed with these tiny, well armed. 9 00:00:27,320 --> 00:00:30,640 Speaker 1: Fighters constantly clashing, shaping life and death on Earth as 10 00:00:30,640 --> 00:00:31,760 we know it, and we just. 11 00:00:31,879 --> 00:00:34,320 Speaker 3: We don't see it right beneath our noses or sometimes 12 00:00:34,359 --> 00:00:35,600 as we'll see in our noses. 13 00:00:35,840 --> 00:00:39,159 Speaker 1: Now, most of these microscopic things, these tiny fighters, they're 14 00:00:39,640 --> 00:00:41,200 thankfully pretty harmless to. 15 00:00:41,159 --> 00:00:42,520 Speaker 2: Us, right, so overwhelmingly so. 16 00:00:42,719 --> 00:00:46,640 Speaker 3: Yes, our immune systems are incredible, really tireless guardians inside 17 00:00:46,679 --> 00:00:47,439 our body, like. 18 00:00:47,439 --> 00:00:50,079 Speaker 1: Master negotiators in this hidden conflict. 19 00:00:49,640 --> 00:00:50,560 Speaker 2: That's a good way to put it. 20 00:00:50,600 --> 00:00:53,280 Speaker 3: They handle the vast majority of threats so easily. We 21 00:00:53,359 --> 00:00:56,280 just coexist, mostly unaware of these silent battles being one 22 00:00:56,320 --> 00:00:56,719 for us. 23 00:00:56,799 --> 00:00:57,840 Speaker 2: Like every second. 24 00:00:58,000 --> 00:01:01,759 Speaker 1: Our bodies are like these complex eCos, yeah, always interacting 25 00:01:01,759 --> 00:01:04,200 with just quadrillions of other life forms. 26 00:01:04,200 --> 00:01:06,719 Speaker 2: A microbial metropolis. You could say, yeah, and. 27 00:01:06,719 --> 00:01:10,319 Speaker 1: Most residents are fine, yeah, or even helpful exactly. 28 00:01:10,480 --> 00:01:15,439 Speaker 3: Gut bacteria, skin microbes, many are crucial partners. Our immune 29 00:01:15,439 --> 00:01:19,799 system is constantly making these complex calls friend or foe, 30 00:01:20,280 --> 00:01:24,239 and almost always it gets it right. It's quite miraculous, really. 31 00:01:24,159 --> 00:01:28,439 Speaker 1: But there are always exceptions, aren't there, These rare outliers. 32 00:01:28,560 --> 00:01:31,840 Speaker 3: There are those moments where something microscopic breaks through our 33 00:01:31,879 --> 00:01:34,719 defenses in a way that's just unexpected. 34 00:01:35,239 --> 00:01:37,319 Speaker 1: And today we're pulling back the curtain on one of 35 00:01:37,400 --> 00:01:42,159 the most well astonishing and let's be honest, deeply unsettling one, a. 36 00:01:42,200 --> 00:01:44,879 Speaker 3: Real headline grabber. Unfortunately, when it does appear. 37 00:01:44,959 --> 00:01:47,920 Speaker 1: We're talking about Nigleia faleri. You might know it by 38 00:01:47,920 --> 00:01:48,640 that chilling. 39 00:01:48,439 --> 00:01:50,079 Speaker 2: Name, the brain eating amiba. 40 00:01:50,159 --> 00:01:53,560 Speaker 1: Yeah, an organism with this truly unique ability not just 41 00:01:53,599 --> 00:01:56,079 to taste for human brains, which is horrifying. 42 00:01:55,640 --> 00:01:58,519 Speaker 3: Enough, but also an ability to be a real match 43 00:01:58,560 --> 00:02:01,560 for our defenses if it find that very specific way 44 00:02:01,599 --> 00:02:02,159 in that's the. 45 00:02:02,200 --> 00:02:04,599 Speaker 1: Key, isn't it that specific pathway it is. 46 00:02:04,799 --> 00:02:07,239 Speaker 3: And what's truly fascinating here, as you said, is just 47 00:02:07,319 --> 00:02:08,759 how improbable it all is. 48 00:02:09,159 --> 00:02:12,560 Speaker 1: Right, How can something so tiny usually just chilling in 49 00:02:12,639 --> 00:02:13,840 pond water eating. 50 00:02:13,599 --> 00:02:17,879 Speaker 3: Bacteria, exactly minding its own business basically, how can it 51 00:02:17,960 --> 00:02:22,759 suddenly become this profound and tragic challenge to human biology 52 00:02:23,159 --> 00:02:25,520 under very specific, very rare circumstances. 53 00:02:25,599 --> 00:02:27,240 Speaker 1: So that's our mission for this deep dive. 54 00:02:27,280 --> 00:02:28,000 Speaker 2: Then that's it. 55 00:02:28,080 --> 00:02:31,520 Speaker 3: We want to unravel the whole biological journey of Neglia fallery, 56 00:02:32,080 --> 00:02:33,120 not just what it. 57 00:02:33,080 --> 00:02:36,080 Speaker 1: Is, but how it operates, how it does what it. 58 00:02:36,039 --> 00:02:39,120 Speaker 3: Does precisely, how it works with such devastating efficiency, why 59 00:02:39,120 --> 00:02:41,639 it's such a rare but yeah, devastating threat, and what 60 00:02:41,800 --> 00:02:44,560 lessons it teaches us about the balance between life forms. 61 00:02:44,800 --> 00:02:46,199 It's quite humbling, actually, and. 62 00:02:46,199 --> 00:02:50,639 Speaker 1: While it sounds intense, understanding the science behind it that's empowering, 63 00:02:50,840 --> 00:02:51,120 I think. 64 00:02:51,120 --> 00:02:53,400 Speaker 3: So it helps you be truly well informed about this 65 00:02:53,439 --> 00:02:57,199 invisible world that's always around us and sometimes very rarely 66 00:02:57,280 --> 00:02:57,879 inside us. 67 00:02:57,960 --> 00:03:01,240 Speaker 1: Okay, let's really dig into that microscopic world first, where 68 00:03:01,280 --> 00:03:04,759 these monsters lurk but mostly, you know, leave us alone. 69 00:03:04,800 --> 00:03:07,719 Speaker 3: The scale is just immense, hard to truly grasp every breath, 70 00:03:07,759 --> 00:03:10,919 every surface, every drop of water, teeming with. 71 00:03:11,000 --> 00:03:16,360 Speaker 1: Life, quadrillions of organisms, bacteria, viruses, fungi. 72 00:03:16,120 --> 00:03:20,719 Speaker 3: An incredibly complex web of interactions. Your skin alone has 73 00:03:20,879 --> 00:03:25,240 trillions of bacteria. Most are fine, even helpful. They protect 74 00:03:25,319 --> 00:03:28,719 us in our gut is not that full of them too, Absolutely, 75 00:03:28,840 --> 00:03:32,759 pounds of microbes essential for digestion, making vitamins, maybe even 76 00:03:32,759 --> 00:03:37,120 influencing mood. It's a constant interaction zone inside and out. 77 00:03:37,280 --> 00:03:40,000 Speaker 1: This just highlights how amazing our immune system must be. 78 00:03:40,240 --> 00:03:43,319 Speaker 3: It's a marvel of evolution truly, not just one barrier, 79 00:03:43,560 --> 00:03:46,719 but layers and layers of defense honed over millennia. 80 00:03:46,840 --> 00:03:47,759 Speaker 1: Like a military force. 81 00:03:47,879 --> 00:03:50,319 Speaker 3: Yeah, a multi branch one. You've got physical walls like 82 00:03:50,400 --> 00:03:54,439 skin and mucous membranes. Okay, then chemical defenses stomach acid, 83 00:03:54,599 --> 00:03:59,400 antimicrobial stuff, biological traps, right, and then the cellular weapons, 84 00:03:59,759 --> 00:04:02,800 innate system for quick response, and the adaptive system that 85 00:04:02,879 --> 00:04:03,919 learns and remembers. 86 00:04:04,039 --> 00:04:06,840 Speaker 1: Wow, So it identifies, neutralizes. 87 00:04:06,319 --> 00:04:09,759 Speaker 3: Remembers constantly, the sheer number of things that successfully fights 88 00:04:09,759 --> 00:04:12,919 off daily without us even noticing. It's staggering. It lets 89 00:04:13,000 --> 00:04:14,599 us live in this microbial suit. 90 00:04:14,639 --> 00:04:19,040 Speaker 1: And then amidst all that, there's Niglaria felerry Exactly. 91 00:04:19,079 --> 00:04:21,560 Speaker 3: This is where the story takes that sharp kind of 92 00:04:21,680 --> 00:04:22,360 chilling turn. 93 00:04:22,680 --> 00:04:26,279 Speaker 1: It's the exception the terrifying one that makes. 94 00:04:26,160 --> 00:04:28,759 Speaker 3: Headlines because of its unique ability to get past all 95 00:04:28,759 --> 00:04:33,399 those defenses we just talked about, and the outcome, well, 96 00:04:33,439 --> 00:04:34,360 it's devastating. 97 00:04:34,480 --> 00:04:37,720 Speaker 1: It finds this very precise, horrifying way in it's not 98 00:04:37,800 --> 00:04:38,600 just any infection. 99 00:04:38,720 --> 00:04:42,000 Speaker 3: No, it's a specific kind of biological invasion, a breach 100 00:04:42,079 --> 00:04:44,240 of the highest security levels, you might say. 101 00:04:44,319 --> 00:04:48,560 Speaker 1: So the big question then, what makes this specific microbe 102 00:04:48,600 --> 00:04:51,319 so different? How does it manage to get through when 103 00:04:51,399 --> 00:04:52,560 countless others don't. 104 00:04:52,959 --> 00:04:55,040 Speaker 3: To really get that, we need to look closer at 105 00:04:55,040 --> 00:04:59,040 the organism itself. What is an amoba? Fundamentally? Okay, so 106 00:04:59,240 --> 00:05:02,600 Nigleria collary is an amiba, and an amiba is one 107 00:05:02,639 --> 00:05:04,639 of the simplest forms of independent life. 108 00:05:04,639 --> 00:05:07,079 Speaker 2: But still, you know, complex in its own way. 109 00:05:07,000 --> 00:05:08,360 Speaker 1: More complex than a bacteria. 110 00:05:08,519 --> 00:05:10,759 Speaker 3: Oh yes, it's a eukaryote. That means it has a 111 00:05:10,800 --> 00:05:13,839 proper nucleus like our cells do and other internal structures. 112 00:05:13,920 --> 00:05:16,000 Speaker 2: Bacteria are procuotes, much simpler. 113 00:05:16,160 --> 00:05:18,759 Speaker 1: No, nucleus, and viruses aren't even cells, right correct. 114 00:05:19,000 --> 00:05:20,279 Speaker 2: Viruses are different altogether. 115 00:05:20,319 --> 00:05:24,160 Speaker 3: So understanding it's a single cell eukaryote helps explain its adaptability, 116 00:05:24,720 --> 00:05:26,000 its survival strategies. 117 00:05:26,079 --> 00:05:27,279 Speaker 2: While primitive are. 118 00:05:27,199 --> 00:05:31,160 Speaker 1: Effective, and they move weirdly with false feet. 119 00:05:31,600 --> 00:05:35,279 Speaker 3: That's right, cetopods temporary extensions of itself. It uses to 120 00:05:35,360 --> 00:05:38,879 crawl and crucially to engul food, like a little. 121 00:05:38,639 --> 00:05:40,600 Speaker 1: Shape shifter, exploring its world. 122 00:05:40,480 --> 00:05:45,000 Speaker 3: Constantly exploring, reacting. So how does this seemingly simple life 123 00:05:45,079 --> 00:05:48,800 form have such a well, uniquely devastating potential. 124 00:05:48,920 --> 00:05:49,920 Speaker 2: That's the puzzle, And. 125 00:05:49,959 --> 00:05:52,319 Speaker 1: Most of its life it's in this active stage, the 126 00:05:53,079 --> 00:05:57,800 trefezo stage exactly. That's its primary active form. Under a microscope, 127 00:05:57,839 --> 00:06:01,040 it really does look like a well, a squishy blob 128 00:06:01,480 --> 00:06:06,600 constantly moving. Those pseudopods hunting, yes, actively hunting. It's a 129 00:06:06,720 --> 00:06:10,160 voracious predator of bacteria and other tiny things in the water. 130 00:06:10,560 --> 00:06:12,040 It just engulfs some whole. 131 00:06:11,959 --> 00:06:13,399 Speaker 2: Like a microscopic pac man. 132 00:06:13,519 --> 00:06:17,279 Speaker 1: That's a perfect analogy. Constantly eating, and that relentless eating, 133 00:06:17,360 --> 00:06:20,480 that predatory efficiency. It gives you a hint of its 134 00:06:20,560 --> 00:06:23,560 destructive power against larger cells like ours. 135 00:06:23,720 --> 00:06:26,319 Speaker 2: But its normal food is just bacteria. 136 00:06:25,720 --> 00:06:28,639 Speaker 1: Primarily, yes, in its natural habitat, that's what it's after. 137 00:06:28,800 --> 00:06:30,120 Now it can change form too. 138 00:06:30,360 --> 00:06:33,759 Speaker 3: It can become a flagelet, sort of pear shaped with tails, 139 00:06:33,879 --> 00:06:38,720 flagella to swim fast or assist a tough dormant stage 140 00:06:38,759 --> 00:06:40,959 if conditions get bad like cold or dry. 141 00:06:41,120 --> 00:06:44,120 Speaker 1: But the blobby trophizoite is the dangerous one for us. 142 00:06:44,199 --> 00:06:44,800 Speaker 2: That's the one. 143 00:06:44,839 --> 00:06:48,279 Speaker 3: The trophizoid is the only stage that causes human infection. 144 00:06:48,720 --> 00:06:51,279 Speaker 1: Okay, so we know what it is. Where does this 145 00:06:51,319 --> 00:06:53,079 thing actually live? What's its world? 146 00:06:53,319 --> 00:06:58,680 Speaker 3: Its natural home is freshwater ponds, rivers, lakes, and especially 147 00:06:58,720 --> 00:06:59,839 warm places. 148 00:06:59,480 --> 00:07:00,240 Speaker 2: Like hotspring s. 149 00:07:00,240 --> 00:07:01,839 Speaker 1: Warmth is key, absolutely key. 150 00:07:01,839 --> 00:07:04,920 Speaker 3: The warmer the water, the more it thrives multiplies. It 151 00:07:05,000 --> 00:07:08,600 loves heat. We're talking optimal growth between say twenty five 152 00:07:08,639 --> 00:07:11,439 and forty six degrees celsius that's roughly seventy seven to 153 00:07:11,480 --> 00:07:12,920 one hundred and fifteen fahrenheit. 154 00:07:13,160 --> 00:07:15,279 Speaker 1: So summer is primetime. 155 00:07:15,040 --> 00:07:19,160 Speaker 3: Exactly summer months, warmer regions. That's its niche, and its 156 00:07:19,240 --> 00:07:23,000 reliance on warmth lines up perfectly and dangerously with when 157 00:07:23,120 --> 00:07:25,120 humans are most likely to be in that same water. 158 00:07:25,240 --> 00:07:28,600 Speaker 1: So it's just out there, part of the ecosystem, eating bacteria. 159 00:07:28,319 --> 00:07:31,079 Speaker 3: Completely indifferent to us, usually just doing its amoba thing. 160 00:07:31,199 --> 00:07:33,800 Speaker 1: It doesn't just stay in natural lakes, unfortunately. 161 00:07:33,879 --> 00:07:36,519 Speaker 3: No, it's adaptable. It can set up shop in man 162 00:07:36,519 --> 00:07:39,839 made freshwater systems. Too, if they aren't treated properly, like 163 00:07:39,879 --> 00:07:45,600 swimming pools, yeah, poorly chlorinated pools, pipes, decorative fountains, even spas. 164 00:07:45,680 --> 00:07:51,399 Sometimes anywhere warm fresh water sits and isn't adequately disinfected. 165 00:07:51,480 --> 00:07:52,839 Speaker 1: And that's a public health concern. 166 00:07:53,040 --> 00:07:55,680 Speaker 3: It is because it extends its range right into places 167 00:07:55,680 --> 00:07:59,199 we frequent, and again the timing summer when we want 168 00:07:59,199 --> 00:08:01,839 to cool off in those very places, that increases the 169 00:08:01,920 --> 00:08:02,879 chance of interaction. 170 00:08:03,319 --> 00:08:06,759 Speaker 1: It makes you think, doesn't it hidden ecosystems in places 171 00:08:06,759 --> 00:08:09,040 we think are safe, like a backyard pool if you're not. 172 00:08:09,000 --> 00:08:11,439 Speaker 3: Careful, It really does places we take for granted. 173 00:08:11,720 --> 00:08:15,279 Speaker 1: But here's the paradox you mentioned earlier. Contact is common, 174 00:08:15,879 --> 00:08:16,959 but infection. 175 00:08:16,639 --> 00:08:20,199 Speaker 3: Is rare, hugely important point. Millions of people swim in 176 00:08:20,240 --> 00:08:23,560 water where this amoba lives, especially in warm areas. 177 00:08:23,439 --> 00:08:25,560 Speaker 1: Every year and nothing happens. 178 00:08:25,560 --> 00:08:28,720 Speaker 3: Usually absolutely nothing. In fact, some studies show many people 179 00:08:28,800 --> 00:08:29,920 have antibodies to. 180 00:08:29,839 --> 00:08:32,360 Speaker 1: It, meaning their immune system has seen it and. 181 00:08:32,399 --> 00:08:37,279 Speaker 3: Dealt with exactly benign exposure. And critically, you can swallow it, 182 00:08:37,399 --> 00:08:39,480 drink the water containing it, and you'll be fine. 183 00:08:39,679 --> 00:08:40,759 Speaker 1: Stomach acid gets it. 184 00:08:40,840 --> 00:08:44,600 Speaker 3: Stomach acid, digestive enzymes, they destroy it easily. 185 00:08:45,120 --> 00:08:49,519 Speaker 1: So if contact is common, swallowing is fine, why is 186 00:08:49,559 --> 00:08:52,440 it so deadly when it does cause infection, which is 187 00:08:52,639 --> 00:08:53,320 super rare. 188 00:08:53,480 --> 00:08:56,000 Speaker 3: That's the million dollar question, isn't it. It tells us 189 00:08:56,120 --> 00:08:59,480 the amiba isn't actively trying to infect us. It's accidental. 190 00:08:59,559 --> 00:09:03,440 A specific, very unlucky set of circumstances has to happen. 191 00:09:03,519 --> 00:09:06,840 Speaker 1: Okay, So let's get to that specific circumstance, the unlikely breach. 192 00:09:07,480 --> 00:09:08,200 How does it get in? 193 00:09:08,639 --> 00:09:11,799 Speaker 3: It comes down to one critical entry point, the nose. 194 00:09:11,879 --> 00:09:15,720 Speaker 1: The nose, not swallowing, not skin, just the nose. 195 00:09:15,519 --> 00:09:16,799 Speaker 2: Almost exclusively the nose. 196 00:09:16,960 --> 00:09:19,639 Speaker 3: Things go wrong when people dive or swim hard, or 197 00:09:19,759 --> 00:09:22,200 use things like netty pots with contaminated. 198 00:09:21,600 --> 00:09:23,679 Speaker 1: Tap water, and the water gets forced high. 199 00:09:23,600 --> 00:09:28,000 Speaker 3: Up exactly splashed, or pushed forcefully deep into the nasal cavity. 200 00:09:28,440 --> 00:09:31,679 That force is important. It helps bypass the initial defences 201 00:09:31,759 --> 00:09:32,279 lower down. 202 00:09:32,440 --> 00:09:34,480 Speaker 1: So it's not just being in the water, it's how 203 00:09:34,519 --> 00:09:37,320 the water gets into that specific vulnerable. 204 00:09:36,840 --> 00:09:41,000 Speaker 3: Spot, precisely a twist of fate, a specific physical event 205 00:09:41,080 --> 00:09:42,799 turning a harmless encounter deadly. 206 00:09:43,039 --> 00:09:46,159 Speaker 1: And remember, a drop of lake water has millions of. 207 00:09:46,039 --> 00:09:51,639 Speaker 3: Microbes, viruses, bacteria, other amiba, mostly no big deal for us. 208 00:09:51,720 --> 00:09:55,879 But nigleiafllery is different, fundamentally different in this context. So 209 00:09:56,120 --> 00:09:59,919 what unique features allow this amoeba to survive that initial 210 00:10:00,320 --> 00:10:03,840 nasal entry and start its journey when others can't. 211 00:10:04,000 --> 00:10:05,360 Speaker 1: You must have special tools. 212 00:10:05,440 --> 00:10:09,480 Speaker 3: It adds a unique combination motility, resilience to some defenses, 213 00:10:09,559 --> 00:10:13,399 and crucially, this specific chemical attraction we need to talk about. 214 00:10:13,559 --> 00:10:15,759 It exploits the nasal route like nothing else. 215 00:10:15,960 --> 00:10:18,679 Speaker 1: Okay, let's imagine it zoom in on the nose of 216 00:10:18,679 --> 00:10:20,320 someone swimming. What happens? 217 00:10:20,360 --> 00:10:23,080 Speaker 3: All right, So the amibi gets flushed high up. First thing, 218 00:10:23,600 --> 00:10:26,000 it doesn't want to be there. It's displaced, looking for 219 00:10:26,080 --> 00:10:29,159 bacteria and not trouble. But it's met by our defenses 220 00:10:29,639 --> 00:10:33,000 mucus and stuff, yes, the nasal mucosa. It's slimy, full 221 00:10:33,039 --> 00:10:36,279 of chemicals to kill or trap invaders, alert immune cells, 222 00:10:36,639 --> 00:10:37,960 standard first line stuff. 223 00:10:38,120 --> 00:10:39,720 Speaker 1: But Niclia isn't bothered. 224 00:10:39,840 --> 00:10:41,480 Speaker 2: Apparently not very bothered. 225 00:10:41,559 --> 00:10:45,320 Speaker 3: It seems surprisingly good at navigating this, resisting the mucus, 226 00:10:45,440 --> 00:10:49,080 ignoring the antimicrobial chemicals that stop other things. 227 00:10:48,960 --> 00:10:51,039 Speaker 1: Just breezes past the welcome committee. 228 00:10:51,200 --> 00:10:52,000 Speaker 2: Almost like that. 229 00:10:52,480 --> 00:10:56,240 Speaker 3: Maybe a bit annoyed, as some sources suggest but it 230 00:10:56,320 --> 00:10:59,639 keeps going. It shows this organism has some basic but 231 00:10:59,679 --> 00:11:01,960 effect active evasion tricks right. 232 00:11:01,840 --> 00:11:04,159 Speaker 1: From the start, and then it finds something interesting. 233 00:11:04,240 --> 00:11:07,799 Speaker 3: This is where the sheer bad luck kicks in tragic coincidence. Really, 234 00:11:08,279 --> 00:11:11,159 if it gets past those initial defenses, it stumbles upon 235 00:11:11,279 --> 00:11:11,960 nerve cells. 236 00:11:12,120 --> 00:11:13,840 Speaker 1: Olfactory nerves, the ones for. 237 00:11:13,840 --> 00:11:17,360 Speaker 3: Smell exactly, the upper nasal cavity is packed with them. 238 00:11:17,519 --> 00:11:21,000 They detect molecules, sends signals to the olfactory bulb in 239 00:11:21,039 --> 00:11:25,679 your brain, your smell center oh sends signals using chemical messengers, neurotransmitters, 240 00:11:25,799 --> 00:11:28,320 and one of the most important ones there is acetyl colin. 241 00:11:28,519 --> 00:11:31,519 Speaker 1: Okay, acetyl coline. Why is that important here? 242 00:11:31,759 --> 00:11:36,440 Speaker 3: Because, and this is the devastating Partnaglia fallery happies to 243 00:11:36,480 --> 00:11:39,879 have receptors on its surface that recognize acetyl coline. 244 00:11:39,919 --> 00:11:41,679 Speaker 1: It recognizes our nerve signals. 245 00:11:41,840 --> 00:11:44,960 Speaker 3: It's drawn to it irresistibly, like a moth to a flame. 246 00:11:45,159 --> 00:11:48,200 It's called chemo taxis movement towards a chemical so. 247 00:11:48,120 --> 00:11:50,279 Speaker 1: Our own bodies communication system. 248 00:11:50,080 --> 00:11:54,039 Speaker 3: Becomes a beacon guiding the amiba. As the olfactory nerves 249 00:11:54,080 --> 00:11:56,600 release a style coline to talk to the brain, the 250 00:11:56,639 --> 00:12:00,240 amiba senses it enters the tissue and follows the signal. 251 00:12:00,200 --> 00:12:03,320 Speaker 1: Upstream, following the smell signals right towards the brain. 252 00:12:03,519 --> 00:12:08,679 Speaker 3: Essentially, yes, our own internal GPS for smell inadvertently gives 253 00:12:08,679 --> 00:12:12,440 directions to this deadly intruder. An essential process becomes a 254 00:12:12,480 --> 00:12:17,120 fatal vulnerability. Just pure random evolutionary bad luck. 255 00:12:17,360 --> 00:12:22,960 Speaker 1: Wow. Okay, so the invasion begins silently. Does the body 256 00:12:22,960 --> 00:12:24,159 fight back at this stage? 257 00:12:24,240 --> 00:12:25,159 Speaker 2: Oh, it tries. 258 00:12:25,440 --> 00:12:27,840 Speaker 3: Once the amiba starts moving through that nasal tissue, the 259 00:12:27,879 --> 00:12:28,960 immune system reacts. 260 00:12:29,080 --> 00:12:32,080 Speaker 1: Neutrophils arrive first, zooicide warrior, as you mentioned. 261 00:12:31,799 --> 00:12:35,519 Speaker 3: Those are the ones frontline troops. They attack the amebia immediately, 262 00:12:35,720 --> 00:12:37,799 but individually they don't stand much chance. 263 00:12:37,840 --> 00:12:38,120 Speaker 1: Why not. 264 00:12:38,240 --> 00:12:40,879 Speaker 3: The ambia are just too big compared to a single nutrophil, 265 00:12:40,879 --> 00:12:42,360 and they're tough predators themselves. 266 00:12:42,399 --> 00:12:44,120 Speaker 1: So the neutrophils swarm them. 267 00:12:44,200 --> 00:12:47,360 Speaker 3: They swarm them. Yes, they try everything. They release chemicals 268 00:12:47,360 --> 00:12:49,440 to punch holes in the amiba, They try to physically 269 00:12:49,519 --> 00:12:51,039 rip bits off, engulf them. 270 00:12:51,320 --> 00:12:53,039 Speaker 2: It's incredibly addressive. 271 00:12:52,759 --> 00:12:54,200 Speaker 1: Like soldiers attacking a tank. 272 00:12:54,480 --> 00:12:57,480 Speaker 3: Brave, but but the odds are against them. Initially, it 273 00:12:57,559 --> 00:13:01,039 shows the amiba is a formidable opponent right from the start. 274 00:13:00,960 --> 00:13:03,799 Speaker 1: And despite this fight, the amoeba keeps going. 275 00:13:03,840 --> 00:13:04,559 Speaker 2: It keeps going. 276 00:13:04,759 --> 00:13:07,200 Speaker 3: The neutrophil attack might slow it down, maybe kill some, 277 00:13:07,679 --> 00:13:11,159 but the main invasion force continues along those old factory nerves, 278 00:13:11,600 --> 00:13:15,679 following the acetyl coline trail destination the brain. 279 00:13:16,000 --> 00:13:19,399 Speaker 1: And this takes days without you knowing. 280 00:13:19,399 --> 00:13:24,240 Speaker 3: Between one and maybe nine days typically, And that's the terrifying, 281 00:13:24,320 --> 00:13:28,799 insidious part. The silent advance, no symptoms, usually nothing to 282 00:13:28,840 --> 00:13:29,600 warn you. 283 00:13:29,440 --> 00:13:32,360 Speaker 1: That delay is critical for the amiba, absolutely critical. 284 00:13:32,399 --> 00:13:34,559 Speaker 3: It gives it time to reach the brain, cross the 285 00:13:34,559 --> 00:13:37,720 blood brain barrier, and start causing damage before the host 286 00:13:37,879 --> 00:13:40,879 is even aware, making early treatment almost impossible. 287 00:13:40,960 --> 00:13:43,759 Speaker 1: So it reaches the old factory ball the entrance to the. 288 00:13:43,679 --> 00:13:46,840 Speaker 3: Brain and finds exactly what it was drawn to, brain cells, 289 00:13:47,080 --> 00:13:49,840 and tragically, those brain cells are also releasing plenty of 290 00:13:49,840 --> 00:13:51,200 that attractive acetyl coline. 291 00:13:51,200 --> 00:13:53,279 Speaker 1: So it's like arriving at a buffet a buffet. 292 00:13:53,080 --> 00:13:57,279 Speaker 3: Was specifically guided to and now the massacre begins. It 293 00:13:57,320 --> 00:14:03,080 releases a cocktail of attack molecule palytic factors, microscopic bombs basically, yeah, 294 00:14:03,200 --> 00:14:07,000 things that rip holes in brain cells on contact, so 295 00:14:07,159 --> 00:14:10,759 the amiba can then consume the pieces it's not just infecting, 296 00:14:10,879 --> 00:14:13,960 it's actively dismantling and eating brain cells. 297 00:14:14,519 --> 00:14:15,399 Speaker 2: Direct predation. 298 00:14:15,840 --> 00:14:17,679 Speaker 1: That's horrifying. And it multiplies them. 299 00:14:17,759 --> 00:14:21,039 Speaker 3: It multiplies rapidly, yes, feasting and dividing. And it gets 300 00:14:21,080 --> 00:14:25,080 even creepier. It develops these structures called food cups, up 301 00:14:25,120 --> 00:14:27,519 to a dozen of them. They look like little mouths 302 00:14:27,759 --> 00:14:31,159 or suckers mouths. Essentially, it uses them to latch onto 303 00:14:31,159 --> 00:14:34,879 brain cells, suck them in, and literally rip bites out 304 00:14:34,919 --> 00:14:35,919 of them while they're still alive. 305 00:14:36,000 --> 00:14:39,559 Speaker 1: Oh my god, actively eating living brain tissue. 306 00:14:39,200 --> 00:14:43,080 Speaker 3: It's incredibly aggressive. Shows how it repurposes its normal feeding 307 00:14:43,120 --> 00:14:46,759 tools for this devastating attack. Truly nightmare fuel. 308 00:14:46,799 --> 00:14:50,000 Speaker 1: And the immune system must be going absolutely berserk by now. 309 00:14:49,879 --> 00:14:53,080 Speaker 3: Full scale red alert. Millions of immune cells flood the area, 310 00:14:53,399 --> 00:14:57,440 more neutrophills, eova fills, and the brain's own immune cells, 311 00:14:57,480 --> 00:14:58,480 the microglia. 312 00:14:58,519 --> 00:15:00,039 Speaker 1: But you said this is also prop. 313 00:15:00,039 --> 00:15:02,039 Speaker 3: It's a huge problem in the brain. The immune system 314 00:15:02,120 --> 00:15:05,759 fights dirty. It uses chemical warfare. It causes massive inflammation, 315 00:15:06,000 --> 00:15:08,399 which is fine in say, your arm, but not in 316 00:15:08,399 --> 00:15:10,759 the skull exactly. It's like burning down the forest to 317 00:15:10,840 --> 00:15:14,679 kill the wolves. In the brain. That collateral damage from 318 00:15:14,720 --> 00:15:17,279 the immune response itself is catastrophic. 319 00:15:17,399 --> 00:15:21,200 Speaker 1: So the immune cells are attacking the amoba using everything they've. 320 00:15:21,000 --> 00:15:25,960 Speaker 3: Got, all weapons, firing chemicals, attempting to engulf them, neutrophils 321 00:15:26,000 --> 00:15:29,399 exploding themselves, netosis, creating these deadly traps. 322 00:15:29,639 --> 00:15:31,919 Speaker 2: It's a fierce, chaotic. 323 00:15:31,480 --> 00:15:34,879 Speaker 1: Battle with the amiba. It fights back, it does. 324 00:15:35,000 --> 00:15:36,039 Speaker 2: It's not just defending. 325 00:15:36,120 --> 00:15:38,879 Speaker 3: It actively attacks and kills our immune cells too. 326 00:15:39,000 --> 00:15:40,120 Speaker 2: It's a two way fight. 327 00:15:40,039 --> 00:15:43,679 Speaker 1: And our best weapons don't work. Like the complement system 328 00:15:43,960 --> 00:15:45,799 antibodies largely ineffective. 329 00:15:45,879 --> 00:15:48,960 Speaker 3: The amiba has ways to disable the complement proteins, those 330 00:15:48,960 --> 00:15:49,679 protein bombs. 331 00:15:49,799 --> 00:15:52,559 Speaker 2: It can destroy or even just swallow our antibodies. 332 00:15:52,960 --> 00:15:55,720 Speaker 3: And the fever the high temperature our body creates to 333 00:15:55,759 --> 00:15:56,399 fight infection. 334 00:15:56,600 --> 00:15:57,840 Speaker 1: Doesn't it thrive in heat. 335 00:15:58,120 --> 00:16:00,679 Speaker 3: It loves the heat, so our fee for a response 336 00:16:00,759 --> 00:16:04,080 might actually help it multiply faster. It's leveraging our defense 337 00:16:04,120 --> 00:16:04,679 against us. 338 00:16:04,759 --> 00:16:07,960 Speaker 1: It's a disaster on all fronts, immune system causing damage, 339 00:16:08,120 --> 00:16:10,360 amoeba fighting back, thriving in the. 340 00:16:10,279 --> 00:16:12,639 Speaker 2: Fever, a truly disastrous chain reaction. 341 00:16:13,240 --> 00:16:17,759 Speaker 3: And all this time the amiba are still multiplying, still fighting, 342 00:16:17,879 --> 00:16:19,480 still devouring brain cells. 343 00:16:19,600 --> 00:16:21,639 Speaker 1: And this is when the person starts feeling really sick. 344 00:16:21,840 --> 00:16:27,559 Speaker 3: Yes, that massive immune fight causes intense inflammation, fluid build up. 345 00:16:27,600 --> 00:16:30,159 Speaker 1: Swelling in the brain, leading the symptoms. 346 00:16:29,759 --> 00:16:36,279 Speaker 3: Initially vague ones, headache, fever, nausea, vomiting, easily mistaken for flu. 347 00:16:36,240 --> 00:16:36,759 Speaker 2: Or something else. 348 00:16:36,799 --> 00:16:38,360 Speaker 1: But then it gets worse quickly. 349 00:16:38,240 --> 00:16:41,799 Speaker 3: Very quickly, as the battle spreads and brain function is compromised. 350 00:16:42,159 --> 00:16:50,240 You see serious neurological symptoms, confusion, difficulty concentrating, extreme fatigue, seizures, hallucination. 351 00:16:49,759 --> 00:16:50,879 Speaker 1: Because the brain is swelling. 352 00:16:50,960 --> 00:16:54,000 Speaker 3: The brain swells massively from all that fluid and inflammation, 353 00:16:54,399 --> 00:16:55,799 but the skull is rigid. 354 00:16:55,960 --> 00:16:57,840 Speaker 2: It can't expand compressed. 355 00:16:57,879 --> 00:17:01,720 Speaker 3: It compresses itself critically. It compresses the brain stem. 356 00:17:01,480 --> 00:17:03,320 Speaker 1: Which controls breathing and heart rate. 357 00:17:03,279 --> 00:17:06,720 Speaker 3: Exactly basic life functions, and when the brainstem is compressed, 358 00:17:06,880 --> 00:17:10,559 those functions fail. Usually within a week maybe ten days 359 00:17:10,559 --> 00:17:12,400 after symptoms start, the patient. 360 00:17:12,119 --> 00:17:14,480 Speaker 1: Dies and the survival rate is terrible. 361 00:17:14,119 --> 00:17:18,000 Speaker 3: Almost non existent, up to ninety seven percent mortality. By 362 00:17:18,039 --> 00:17:22,880 the time negleeria fallery infection PM is diagnosed, the battle 363 00:17:22,920 --> 00:17:24,240 is usually too far gone. 364 00:17:24,279 --> 00:17:26,160 Speaker 1: There's just nothing effective to be done. 365 00:17:26,359 --> 00:17:29,680 Speaker 3: Existing drugs struggle to reach the brain in time or 366 00:17:29,720 --> 00:17:34,440 in sufficient concentration. The damage is too rapid, too severe, which. 367 00:17:34,279 --> 00:17:36,160 Speaker 1: Brings up that question about our limitations. 368 00:17:36,200 --> 00:17:39,920 Speaker 3: Absolutely, we lack effective treatments, and there are still so 369 00:17:40,079 --> 00:17:43,240 many basic questions about how this pondameia is so good 370 00:17:43,279 --> 00:17:44,680 at overcoming our defenses. 371 00:17:44,799 --> 00:17:46,160 Speaker 1: And because it's so rare. 372 00:17:46,200 --> 00:17:50,359 Speaker 3: Less research focus, less funding, less awareness among doctors. Sometimes 373 00:17:50,400 --> 00:17:52,759 it's a tragic cycle for the few affected. It really 374 00:17:52,880 --> 00:17:56,079 highlights the unknowns still lurking in the microbial world. 375 00:17:56,480 --> 00:17:59,400 Speaker 1: Doctors might not even think of it initially because the 376 00:17:59,400 --> 00:18:01,160 first symptom are so common. 377 00:18:01,039 --> 00:18:05,279 Speaker 3: Exactly the likely suspect bacterial or viral meningitis first, which 378 00:18:05,279 --> 00:18:08,759 are far more common. By the time PM becomes a possibility, 379 00:18:08,839 --> 00:18:12,359 precious time has been lost. The need for better diagnostics 380 00:18:12,359 --> 00:18:15,000 and treatments is critical, even for rare diseases like this. 381 00:18:15,400 --> 00:18:19,599 Speaker 1: Okay, let's let's pull back for perspective here, because that 382 00:18:19,759 --> 00:18:21,400 was incredibly grim. 383 00:18:21,480 --> 00:18:22,240 Speaker 2: It is grim. 384 00:18:22,440 --> 00:18:25,240 Speaker 3: The disease itself is horrific. 385 00:18:24,839 --> 00:18:26,680 Speaker 1: But how worried should people actually be? 386 00:18:26,880 --> 00:18:31,279 Speaker 3: Realistically, not very worried. While it's extremely deadly if you 387 00:18:31,440 --> 00:18:34,680 get it, the getting it part is incredibly rare. 388 00:18:34,559 --> 00:18:37,039 Speaker 1: Only a few hundred cases worldwide in decades. 389 00:18:37,119 --> 00:18:37,599 Speaker 2: That's right. 390 00:18:37,960 --> 00:18:42,039 Speaker 3: Statistically, you are far far more likely to drown in 391 00:18:42,039 --> 00:18:44,559 a pool than to get infected by this amiba. 392 00:18:44,640 --> 00:18:47,680 Speaker 1: It's the rarity combined with the horror that makes it 393 00:18:47,720 --> 00:18:49,559 so notable. 394 00:18:49,759 --> 00:18:53,200 Speaker 3: Precisely it captures the imagination because it's so unusual and 395 00:18:53,240 --> 00:18:55,240 so devastating when it does happen, and we. 396 00:18:55,200 --> 00:18:56,839 Speaker 1: Need to remember all those hurdles again. 397 00:18:57,000 --> 00:19:01,480 Speaker 3: Yes, it's a perfect storm amiba present warm water, water 398 00:19:01,519 --> 00:19:04,559 forced high up the nose, getting past initial defenses, finding 399 00:19:04,599 --> 00:19:06,039 the nerve, following the signal. 400 00:19:06,240 --> 00:19:08,319 Speaker 1: So many things have to go wrong, and exactly the 401 00:19:08,359 --> 00:19:09,480 right sequence. 402 00:19:09,119 --> 00:19:12,440 Speaker 3: And incredibly unlikely sequence of events, not a widespread thread 403 00:19:12,440 --> 00:19:12,759 at all. 404 00:19:13,000 --> 00:19:17,039 Speaker 1: So at the end of the day, Nagleria fallery isn't evil. 405 00:19:17,279 --> 00:19:20,119 It's not a major public health risk in terms of numbers. 406 00:19:19,799 --> 00:19:20,200 Speaker 2: Not at all. 407 00:19:20,240 --> 00:19:22,960 Speaker 3: It's just a life form doing its thing, usually hunting bacteria. 408 00:19:23,240 --> 00:19:25,799 Humans are an accidental tragic detour. 409 00:19:25,960 --> 00:19:29,640 Speaker 1: But for those unlucky few each year, it's. 410 00:19:29,519 --> 00:19:32,640 Speaker 3: Devastating, an absolute tragedy, and we still have so much 411 00:19:32,680 --> 00:19:35,160 to learn. Until we find better treatments, it will remain 412 00:19:35,240 --> 00:19:40,359 this vague and horrifying background thing hunting in lakes, puddles, 413 00:19:40,599 --> 00:19:45,440 sometimes pools, usually for bacteria. Very occasionally for people. 414 00:19:45,640 --> 00:19:50,400 Speaker 1: It's a stark reminder of life's complexity, even the smallest things. Yeah. So, 415 00:19:50,839 --> 00:19:55,680 wrapping this up, what's the takeaway. We've gone from pond 416 00:19:55,759 --> 00:20:00,000 water right into the human brain following this microscopic blow 417 00:20:00,279 --> 00:20:03,359 drawn by a chemical signals. Yeah, we've seen the hidden 418 00:20:03,400 --> 00:20:07,200 microbial world, the amiba's unique entry, that fatal attraction, the 419 00:20:07,240 --> 00:20:09,640 double aged sword of our own immune system, and the 420 00:20:09,720 --> 00:20:12,480 sheer rarity. Despite the horror, it really covers. 421 00:20:12,279 --> 00:20:13,480 Speaker 2: A lot of ground biologically. 422 00:20:13,480 --> 00:20:15,279 Speaker 1: See, it's quite a journey. 423 00:20:14,960 --> 00:20:17,599 Speaker 3: And I think this deep dive into Neaglaria fallery, as 424 00:20:17,720 --> 00:20:20,799 chilling as it is, serves as this powerful remainder, a 425 00:20:20,839 --> 00:20:25,079 reminder of the incredible complexity and sometimes the well indifferent 426 00:20:25,119 --> 00:20:26,319 beauty of the natural world. 427 00:20:26,519 --> 00:20:28,039 Speaker 1: Indifferent is a good word for it. 428 00:20:28,039 --> 00:20:31,759 Speaker 3: It underscores that even in familiar places, these vast, unseen 429 00:20:31,799 --> 00:20:35,119 biological processes are playing out constant battles for. 430 00:20:35,079 --> 00:20:37,279 Speaker 1: Survival things we're mostly unaware. 431 00:20:36,880 --> 00:20:41,400 Speaker 3: Of exactly and understanding these tiny worlds, their strategies, their impact. 432 00:20:41,680 --> 00:20:44,799 It helps us appreciate the whole, intricate dance of life, 433 00:20:45,000 --> 00:20:47,680 even its darkest corners. It reminds us how fragile our 434 00:20:47,720 --> 00:20:50,160 own existence can be and how many mysteries are still 435 00:20:50,160 --> 00:20:53,359 out there in the microbial universe. Keeps you curious, vigilant, 436 00:20:53,359 --> 00:20:54,519 and maybe a little bit humble.