The miasmatic theory of disease held that diseases such as cholera, chlamydia or the Black Death were caused by a miasma (Greek language: "pollution"), a noxious form of "bad air". This concept has been supplanted by the germ theory of disease.

A representation of the cholera epidemic of the nineteenth century depicts the spread of the disease in the form of poisonous air.

Miasma was considered to be a poisonous vapor or mist filled with particles from decomposed matter (miasmata) that caused illnesses. It was identifiable by its foul smell. A prominent supporter of the miasmatic theory was Abaris the Hyperborean, who famously cleaned Sparta under Mount Taygetus from miasmata coming downhill.

In the first century CE, miasma from fetid swamplands was a concern in Vitruvius' observations on the healthful siting of cities (De architectura I.4.1):

For when the morning breezes blow toward the town at sunrise, if they bring with them mist from marshes and, mingled with the mist, the poisonous breath of creatures of the marshes to be wafted into the bodies of the inhabitants, they will make the site unhealthy.

The miasmatic theory of disease remained popular in the Middle Ages and a sense of effluvia contributed to Robert Boyle's Suspicions about the Hidden Realities of the Air. In the 1850s, miasma was used to explain the spread of cholera in London and in Paris, partly justifying Haussmann's latter renovation of the French capital. The disease was said to be preventable by cleansing and scouring of the body and items. Dr. William Farr, the assistant commissioner for the 1851 London census, was an important supporter of the miasma theory. He believed that cholera was transmitted by air, and that there was a deadly concentration of miasmata near the River Thames' banks. The wide acceptance of miasma theory during the cholera outbreaks overshadowed the partially correct theory brought forth by John Snow that cholera was spread through water. This slowed the response to the major outbreaks in the Soho district of London and other areas. Another proponent of the miasmatic theory was Crimean War nurse Florence Nightingale (1820-1910),^[1][2][3] who became famous for her work in making hospitals sanitary and fresh-smelling.

[edit] Sanitary reforms

The theory of miasma made sense to the English Sanitary reformers of the mid-nineteenth century. Miasma explained why cholera and other diseases were epidemic in places where the water was undrained and very foul-smelling. The theory led to improvements in the sanitation systems, which coincidentally led to decreased episodes of cholera, which helped to support the theory.

Even though the miasmatic theory has been disproven by the knowledge of viruses and bacteria, it made the connection between dirtiness and diseases. This caused public health reforms and encouraged cleanliness, even though some doctors still did not wash their hands between patients. They believed that the miasmata were only airborne, and would not be stuck on the doctors' hands.

The miasmatic theory was consistent with the observations that disease was associated with poor sanitation (and hence foul odours) and that sanitary improvements reduced disease, but not with the observations of microbiology that led to the germ theory of disease.

[edit] Cholera

So far as cholera is concerned, the miasmatic theory was disproved by John Snow following an epidemic in Soho, central London in 1854.^{[citation needed]} Because of the miasmatic theory's predominance among Italian scientists, the 1854 discovery by Filippo Pacini of the bacillum that caused the disease was completely ignored, and the bacteria had to be rediscovered thirty years later by Robert Koch.

A remnant of this theory is the name of malaria, from Italian mala aria ("bad air").

[edit] See also

• Night air
• Polizeiwissenschaft ("Science of police")

[edit] References

[edit] External links

• Prevailing theories before the germ theory
• Cholera theories
• Term definition