The (Second) Most Deadliest Virus on Earth

The (Second) Most Deadliest Virus on Earth

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Few of the monsters that evolution created have been so successful at hurting us as the variola virus, responsible for smallpox. The carnage it caused was so terrible and merciless that it compelled humankind, for the first time, to act truly globally. It was one of the greatest wins of our species over the ancient powers of nature, all made possible by… cows.


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44 Responses

  1. Kurzgesagt – In a Nutshell says:

    Continue learning about the fascinating world of biology with our Human Cell Poster, exclusively available here:

  2. Saban Labbad says:

    That cow deserves respect, what a legend.

  3. hybredmoon says:

    Before my first deployment I received a small-pox vaccine. The medic used a small forked needle dipped in the vaccine to puncture the skin of my shoulder and wiggle it around a bit. The result was a necrotic lesion about the size of a half-dollar coin, a fever, and two or three days of body aches. I still have a scar on my shoulder from the inoculation site. I had ONE lesion and was in bed for 3 days feeling rough while my body fought a version of the disease that wasn’t even effective against my species. I cannot IMAGINE the suffering that someone with an actual case of small pox must have endured. By the end, death must’ve been a sweet release. It’s frightening to see the caliber of threat required to get humanity to work together.

    • EvilAng3la says:

      Reading about the ways that some people died from smallpox is nightmare material. Some of the most severe cases would result in people having their skin sloughing off. Photos are also terrifying. I just wish I could personally thank all the people involved in making sure that I never, ever had to worry about catching this horrible disease.

    • AaronShenghao says:

      May countries still administered the vaccine as late as the 90’s I have a scar from it too.

    • D00mnoodle says:

      Were all of these issues because of the vacine or because the forked needle wasn’t properly sterilized? Because that can also cause serious infections

    • Cak says:

      ​@D00mnoodleyea I was thinking that too

  4. Christopher Brielman says:

    It is worth noting that Smallpox was the *ideal* virus to eradicate. Its particular traits made it extremely deadly but also extremely easy to target by coordinated vaccination efforts. Most other viruses are nowhere near so considerate.

    • Foolishball says:

      All viruses are easy to target except for ones with extremely long incubation period since most viruses are extremely host specific

    • Gunnery Sergeant Hartman says:

      ​@Foolishball It’s a bit of a double edge sword; yes, lot of viruses are host specific and therefore are easily detectable. However, viruses also rapidly evolve thanks to how easy it is for mRNA (the chemical method by which a virus hijacks it’s host) to mutate due to the lack of proofreading proteins. These mutations could very easily give viral offspring immunities that it’s parents never had the luxury of having.

      That and while we have one or two kids that take 18 years to mature, viruses have multiple hundreds of progeny that mature seconds after they’re born; they just evolve way faster than we do out of sheer numbers

    • SqueakSquawk4 says:

      IIRC the main 2 factors were that it was human-only, and that symptoms showed BEFORE it was contagious

    • Foolishball says:

      @Gunnery Sergeant Hartman yeah it is true that RNA viruses evolve way faster than DNA viruses. There are more DNA viruses but most of them are not deadly disease except the ones that cause cancer like HPV. My point does not hold much water in case of highly mutatable viruses.

  5. Ohh Crap Guy says:

    When I was growing up, my family had a World Book encyclopedia from 1974, and later got ahold of one from 1982. As some of us do, I went through that weird phase where you get fascinated by diseases, and I was fixated on Smallpox. It just so happened that this coincided with us getting the newer version of the set.

    At the time, I just thought it was funny that the older one was “wrong” since smallpox had been eradicated and it was out of date.

    But one of the things I noticed at the time, which is truly striking today, is that the first sentence in the different editions were nearly identical, except that the second had one miniscule difference. It had a most terrible word replaced with a most lovely one.

    “is” had become “was”

    • Burn Angel says:

      That last bit reminds me of a Vsauce video from some years ago.
      Edit: nope, it was an exurb1a video, I’m dumb haha.

    • Jokes with Mitochondria says:

      Smallpox was scary

    • The real Speedwagon says:

      It’s truly amazing when such a terrible disease that *was* the scourge of humanity for countless millennia becomes a was. But it’s also terrifying that to an extent it still exists. Not just in token laboratories, but frozen in Siberian permafrost, waiting to melt and unleash it’s horror on the world again.

    • Francisco Villa says:

      Wow so deep. Then everyone clapped alongside exhurbia

  6. Aamir Razak says:

    Amazing how from such humble beginnings and human cooperation, we were able to eradicate an entire disease. It’s inspiring, hope we can unite like that more in the future

    • Crazy Luigi says:

      Wish we did that from the period of late 2019-2021 when we had the chance to instead of have leaders try and hope for it to go away on its own before turning that shit into a political issue when it was always going to be a human issue…

    • Universal 🌌 Documents | Mahapushpa Cyavana says:

      There was like 1 guy and hearsay. Then a bunch of copying.

    • Jza says:

      Yeah if only there was some recent opportunity to do just that yet apparently it was all ‘fake news’

    • Boomy says:

      Well maybe we should all come together and eradicate those who are against it

  7. LonkABonk says:

    This is a lesson that when humanity comes together, we can beat even the most horrible things on earth

  8. Harsh says:

    If you didn’t knew , the last person to die from small pox was Janet Parker. In 1978, Parker was a medical photographer at England’s Birmingham University Medical School. She worked one floor above the Medical Microbiology Department where staff and students conducted smallpox research.

  9. Kristina says:

    In 1972, Yugoslavia had an outbreak of smallpox, it was the largest outbreak in Europe after the Second World War. I recently read about it, very fascinating! They vaccinated eighteen (18) million citizens in about one month.

    • ViktorSRBPvP says:

      Da, takođe i Srbija ima taj virus u labaratoriji obezbeđen. Yes, Serbia also has a sample of it secured in a lab.

    • Deboned Butter says:

      @ViktorSRBPvPYup. There are two places where the virus is still contained as the video said.

      The one one in Serbia, and the one in the USA.

  10. Whisper says:

    Smallpox being eradicated is probably one of the largest achievements humanity has ever done, at least in my opinion. It gives me so much pride in humanity to know that we have eradicated it.

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