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  • Nipah, Hendra, Ebola, Marburg, SARS.

  • These are some of the world's scariest viruses.

  • Hemorrhagic fevers like Ebola are extremely fatal.

  • They kill up to 90 percent of people infected while SARS, a coronavirus, has a lower mortality rate but spreads incredibly rapidly.

  • All of these nasty pathogens have surfaced in humans in just the last 50 years, and they are all carried by bats.

  • Which, to be clear, really isn't bats' fault.

  • The recent rise in outbreaks is likely due to humans and our animals creeping ever farther into bats' territory, especially in the tropics.

  • In Malaysia, for example, the spread of commercial pig farms into bat-inhabited forests led to the first human outbreakvia pigsof Nipah.

  • And in Australia, human Hendra cases are cropping up as destruction of native forests forces fruit bats to feed in suburban gardens.

  • But still, bats do appear to carry more human-killing diseases than pretty much any other animal.

  • One big reason is that, with a few notable exceptions, bats love company.

  • Different kinds of bats often roost together in huge numbers and close quarters, which helps viruses spread not just between individuals, but also between species.

  • What's more, most infected bats don't die.

  • They live pretty normal bat livesflapping around and giving the viruses time to spread.

  • In fact, flight may be the reason bats are so resilient to infection.

  • As a rule, mammals can't produce the immense amount of energy needed for flight without also producing a lot of reactive waste products that damage our DNA.

  • So when our bat cousins took to the air, they leveled up their in-flight DNA damage repair kits and other defenses, including specialized cells that keep viral invaders in check.

  • So bats can survive the deadly viruses, but what may matter even more, for humans anyway, is how the viruses survive the bats.

  • Nasty as they are, most viruses are also extremely finicky.

  • In order to thrive, they require the perfectly controlled climate inside a normal, resting, on-the-ground mammal.

  • But when bats take to the air, their internal temperatures cruise to around 40°C.

  • Those frequent in-flight saunas are far too toasty for your average virus, but a few hardy viruses have evolved to tolerate the heat, which, incidentally, means they can definitely weather a meager human fever.

  • Essentially, flight may have helped bats gain virtual immunity to viruses AND trained viruses to be virtually immune to us.

  • Stupid flying.

  • So, what should we landlubbers do?

  • We need bats for insect control and pollination, and a whole bunch of other things.

  • Maybe we could even learn some immune tricks from them, like how to be really good at not getting cancer!

  • Plus, bats aren't the biggest carriers of human disease.

  • Humans are, just do the math.

  • Perhaps we'd be better off leaving bats alone, and trying to control the spread of diseases carried by a different kind of flying mammal.

Nipah, Hendra, Ebola, Marburg, SARS.

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B1 US flight bat human spread mammal ebola

Why Do Bats Carry So Many Diseases? (like Coronavirus)

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    Seraya posted on 2020/02/22
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