5 ms·

> a noxious form of "bad air", also known as night air. The theory held that epidemics were caused by miasma, emanating from rotting organic matter. Not far fr

> a noxious form of "bad air", also known as night air. The theory held that epidemics were caused by miasma, emanating from rotting organic matter. Not far from the truth either, quite impressive for 1000 years ago.

gruez 6y ago
It's very far from the truth imo. There are diseases that are airborne, but most aren't spread by rotting organic matter. It also ignores the other routes of infection (eg. food/water). The only thing it got right was "disease can spread through air". The magnitude of the effect is probably off too. AFAIK the miasma was thought to extend at least a few hundred feet (ie. encompassing entire neighborhoods), but I don't know of any disease that can spread that far through the air.
- im3w1l 6y ago
  How far the disease can spread would depend on sources and sinks, no? If you have a huge pile of infected dead bodies in a "bowl shaped terrain" with little wind, maybe that would do it? Add a temperature inversion* for good measure. https://i2.wp.com/www.naturphilosophie.co.uk/wp-content/uploads/2016/12/Normal_Conditions_versus_Temperature_Inversion_Diagram_UnderstoryWeather.jpg?ssl=1 https://i2.wp.com/www.naturphilosophie.co.uk/wp-content/uplo...
  - gruez 6y ago
    >How far the disease can spread would depend on sources and sinks, no? By air alone? How far can it possibly spread? Can you get measles if you walked within 100ft of a mass grave? miasma theory would say yes, but I doubt that's actually the case. If you include other forms of transmission (eg. insects, animals, food/water), then it can definitely spread miles away, but this goes back to my original point of only being correct about disease being (loosely) correlated by distance. But even then it gets a bunch of stuff wrong. A rat with the bubonic plague stowed away on a ship can infect people hundreds of miles away, for instance. You could also live next to a mass grave and be fine as long as you have mesh windows and boiled your drinking water.
    - im3w1l 6y ago
      It's a good point about other forms of transmission, but I think the air alone is an interesting question. What would be the limiting factor on how far it can spread? Do the particles deactivate after a while in the air? Or is it that the concentration is not high enough? Latter case, wind patterns would matter a lot. Surely, when authorities talk about diseases being able to spread x many feet, it ignores many factors and is meant to be an actionable simplification that works in a statistical sense.

gruez 6y ago

It's very far from the truth imo. There are diseases that are airborne, but most aren't spread by rotting organic matter. It also ignores the other routes of infection (eg. food/water). The only thing it got right was "disease can spread through air". The magnitude of the effect is probably off too. AFAIK the miasma was thought to extend at least a few hundred feet (ie. encompassing entire neighborhoods), but I don't know of any disease that can spread that far through the air.

im3w1l 6y ago
How far the disease can spread would depend on sources and sinks, no? If you have a huge pile of infected dead bodies in a "bowl shaped terrain" with little wind, maybe that would do it? Add a temperature inversion* for good measure. https://i2.wp.com/www.naturphilosophie.co.uk/wp-content/uploads/2016/12/Normal_Conditions_versus_Temperature_Inversion_Diagram_UnderstoryWeather.jpg?ssl=1 https://i2.wp.com/www.naturphilosophie.co.uk/wp-content/uplo...
- gruez 6y ago
  >How far the disease can spread would depend on sources and sinks, no? By air alone? How far can it possibly spread? Can you get measles if you walked within 100ft of a mass grave? miasma theory would say yes, but I doubt that's actually the case. If you include other forms of transmission (eg. insects, animals, food/water), then it can definitely spread miles away, but this goes back to my original point of only being correct about disease being (loosely) correlated by distance. But even then it gets a bunch of stuff wrong. A rat with the bubonic plague stowed away on a ship can infect people hundreds of miles away, for instance. You could also live next to a mass grave and be fine as long as you have mesh windows and boiled your drinking water.
  - im3w1l 6y ago
    It's a good point about other forms of transmission, but I think the air alone is an interesting question. What would be the limiting factor on how far it can spread? Do the particles deactivate after a while in the air? Or is it that the concentration is not high enough? Latter case, wind patterns would matter a lot. Surely, when authorities talk about diseases being able to spread x many feet, it ignores many factors and is meant to be an actionable simplification that works in a statistical sense.