Causes of Smallpox

‘Our great Business… is to get Intelligence of those Causes.’

John Woodward, The state of physick: and of diseases (London, 1718), p. 59.

smallpox1
Jean Claude Adrien Helvétius, An essay on the animal oeconomy.
Together with observations upon the small pox (London, 1723), titlepage.

Jean Claude Adrien Helvetius (1685-1755), writing on smallpox in 1722, outlined divergent opinions on the cause of smallpox: was it due to ‘the excessive Fixedness and Grossness of the Humour, by which it was render’d unable to throw it self out of a very thick Blood’ as some physicians argued? Or was the cause quite the contrary: a case of ‘too violent an Agitation in the Blood’? Helvetius saw the true cause of smallpox as lying in the dominant humoral understanding of early modern medicine:

‘The General Cause of the Small-Pox, as we have already hinted, is an Humour or Ferment contain’d in the Lympha. This Humour disengages it self sooner or later, in greater or less Quantities, according as it is more or less entangled. The Quality of the Air we breathe, and the Regimen we observe, do likewise very much contribute to hasten or retard its Solution. When once it begins to disengage it self, it unites by Degrees with the Lymphatic Juices, which go off through the Glands of the Primae Viae. There it is collected, there it diffuses it self, and corrupts the Chyle by its Mixture with it. Then succeed Pains in the Stomach, Reaching, Vomiting, and other Accidents, the ordinary Forerunners of the Small-Pox. Part of this Morbisick Matter being left in the Stomach, is evacuated by Stool or Vomiting. Part of it mixing with the Blood, gives to the Paroxysms of the Fever their Violence and Duration: by Means of which, the Humour at last is wholly disengaged….

When all the Parts of this Ferment are let loose, when they are broken and are attenuated, they unite with the Humour which is discharged by Perspiration, and along with it are thrown upon the Cutaneous Glands: This Union renders the Perspirable Humour a great deal more gross, and obstructs it in the Excretory Ducts of those Glands; or in the Secretory Vessels, when these others are already obstructed. Hence is form’d that little Pimple or Rising, which is perceiv’d at the Beginning of the Eruption, and which afterwards becomes the Centre of the Pustle.’

(Helvetius, pp. 129-30).

John Woodward (1665/1668–1728), keen to draw attention to the fact that smallpox was a relatively new disease, pointed to gluttony as the true cause. Here the guilty culprits were excessive tea-drinking and too much chocolate, new products which were unknown to our ‘wise, stout, healthy Ancestors’ and which were purveyed to unsuspecting eaters by the ‘late great Multiplication of Pastry-Cooks in the City’. As Levine (2004) has pointed out, Woodward’s understanding of disease laid much stress on the role of bilious salts in the stomach and this preoccupation with the stomach as the seat of disease may be seen in this work.

For information on the actual cause, the virus strains Variola major and Variola minor and on smallpox today see the following websites:

http://www.who.int/csr/disease/smallpox/en/index.html
http://www.mayoclinic.com/health/smallpox/DS00424/DSECTION=causes
Selected Sources

Levine, J. M. (2004) ‘Woodward, John (1665/1668–1728)’, Oxford Dictionary of National Biography (Oxford: Oxford University Press).
Helvetius, Jean Claude Adrien, medicine français, (1685-1755), Nouvelle Biographie Générale.