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Why do you get a fever when you're sick? - Christian Moro

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There are many mysteries around fever, but we do know that all mammals, some birds and even a few invertebrate and plant species feel fever’s heat. It has persisted for over 600 million years of evolution. But it has a significant cost: for every degree increase in temperature, there’s a 12.5% increase in energy required. So, why and how does your body produce a fever? Christian Moro investigates.

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Your body’s core temperature is maintained within relatively defined limits. However, sometimes when fighting an infection, it heats up to produce a fever. Why does this occur, and what’s happening inside the body to cause this response?

Fever is common across the animal kingdom, where it’s remained a noticeable response to infection for millions of years. It’s observed in mammals, reptiles, amphibians, fish, and even some invertebrate species. However, what’s particularly interesting is our longstanding human fascination with fever. Parmenides of Elea, the founder of metaphysics, in 500BC stated “Give me the power to produce fever and I'll cure all disease”. Hippocrates also characterised and wrote widely about fever in the 5th century BC.

In the 1600’s English physician Thomas Sydenham wrote that “Fever is nature’s engine which she brings into the field to remove her enemy”. It’s incredible to think that even nowadays we wonder and ponder many of the same concerns as our predecessors. Infection has always been a concern for humans, but nowadays we’re very fortunate to have access to modern medicines, such as antibiotics, which can help us fight many of the fever-inducing pathogens. Get more insights into fever here.

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Meet The Creators

  • Educator Christian Moro
  • Director Igor Coric
  • Narrator Addison Anderson
  • Sound Designer Stephen LaRosa
  • Director of Production Gerta Xhelo
  • Editorial Director Alex Rosenthal
  • Producer Bethany Cutmore-Scott
  • Editorial Producer Cella Wright
  • Script Editor Emma Bryce
  • Fact-Checker Eden Girma

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