Causes
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Causes of Fevers
Thomas Sydenham (1624-89), one of the foremost English physicians of his day, tended to eschew the more theoretical approaches to fevers, preferring instead to base his approach on that of Hippocrates himself: a careful observation of cases leading to judgments on treatment.
Thomas Sydenham, Methodus curandi febres (London, 1676), portrait.
Sydenham’s approach led him to the unenviable conclusion that each individual fever had to be fought as an individual disease, so rapidly did fevers change:
‘But this I am sure of by many Observations, that the abovemention’d species of Diseases, especially continual Fevers, do very much differ; for that method which is successful one year, may perhaps be destructive another. And when I had once happily met with a method of Cure, which this or that kind of Fever did particularly require, I scarce ever fail’d of Success, respect being had to the Temperament, and Age, and the like, till the Species was extinct; but when a new one did arise, I was in doubt which way I should steer, so as to be serviceable to my Patient; and unless I took great Care, and used my utmost Endeavours, I could scarce help, but that one or two of those I had first in hand would be in great danger, till I had found out the Genius of the Disease, and then I could again proceed readily to the curing of it.And tho’ I have observ’d with as much diligence as possibly I could, the various Dispositions of divers Years, as to the manifest qualities of the Air, that from thence I might learn the Causes of this great variety of Epidemical Diseases, yet I have receiv’d no Benefit thereby; for I perceive that Years that do agree as to the manifest Temper of the Air, are infested with various Diseases; and so on the contrary….
… Moreover, there are particular Temperaments of the same Year, as I may say, wherein, tho’ according to the manifest qualities of the Air, those Fevers that follow the general Constitution of the Year are more or less Epidemical, or come sooner or later; yet chiefly those Fevers that come every Year (which therefore we call Intercunents) owe their Rise to this or that manifest Temper of the Air, viz, a Pleurisie, Quinsie, and the rest of this sort, which most commonly proceed from sudden heat, following presently a long and severe cold Season. Therefore ‘tis probable, that the sensible qualities of the Air may be instrumental in producing those Fevers which exert themselves in every Constitution, but not as to those that are peculiar to any one Consitution: We must confess, that the abovemention’d qualities of the Air do more or less dispose out Bodies to generate this or that Epidemick Disease, which is likewise to be said of any Error in the six Nonnaturals.’
Sydenham, The Whole Works (London, 1696),pp 4-6.
Sydenham’s works were translated into English by John Pechey, whose own Collections of acute diseases (London, 1691) was also collected by Worth. Pechey, like his hero, was at pains to point to the seasonal nature of fever epidemics:
‘…We must remember that in Autumn 1677, Intermittent Fevers first advanc’d and increas’d dayly, and were Epidemic till they came to their state; afterwards they gradually decreas’d and so rarely appear’d the last Years of this Constitution, that they cou’d not be counted Epidemical; and on this account we must likewise take notice that the two last Years of the Constitution now going off, had two very severe Winters, especially the last save one, viz the Year 1683, in which the season was so extreamly cold, that no Man living ever saw the like, as to the intense degree of cold, and the long time it held….I can’t certainly say whether the change of this Constitution is to be attributed to the alteration of the manifest qualities of the Air, which succeeded for those two Winters; for I have observed that alterations as to the sensible qualities of Years how different soever, have not produc’d species of Epidemic Diseases; and that a certain series of Years (tho one Year has differ’d from another, as to outward appearance and temperament) have notwithstanding all agreed in the production of the same species of stationary Fevers; which when I had seriously consider’d, I was of the Opinion, as I have mention’d in another place, that the change of a Constitution chiefly depends on some secret and hidden alteration in the Bowels of the Earth passing through the whole Atmosphaere, or from some influence of the Coelestial Bodies. Tho’ tis to be noted here, what when the Depuratory Fever heretofore went off, a very dry and violent Frost from the beginning of Winter 64, froze up all things, at which time, as soon as the Frost went off, and a Pestilential Fever, soon after the Plague began to rage. But howsoever this be, the Fever which we now Treat of, began at the time aforesaid, to wit in Feb. 8o. and was more spread through all the parts of England, and more Epidemic in other places than here in London, the Year before and this Year….’
Pechey, Collections of acute diseases (London, 1691),pp 65-7.
But if Sydenham was content to avoid the more theoretical discussion of what exactly caused fever in favour of development of methods of treatment, other physicians focused on the genesis of the disease. Edward Worth’s copy of Sir Richard Blackmore’s A treatise upon the small-pox (London, 1732), contains a typical discussion of different kinds of fevers and their causes:
‘A Fever is an inordinate Elevation of the oyly or fiery Parts of the Blood, by which the balance of Power between the active and governing Principles being broken, a great Tumult and Disorder arises in the animal Oeconomy, attended with immoderate heat and Thirst, too high and often too swift a Pulse, Head-ake, and sickness of Stomach, and is either original in the Blood and Humours of the Body, or secondary and derived from some other previous Distemper. Of the first sort are all Fevers call’d acute, produced by the Admission of noxious Matter into the Blood, while the solid Parts are sound and entire: The Secondary are but an Effect or Symptom of some other Disease, of which Kind are hectick, scorbutick, wandring and white Fevers, which proceed from some antecedent Distemper, and that chiefly in one of the Bowels, and these being slow and lingering, and protracted to a considerable space of Time, are therefore called Chronical.Original or primary Fevers may be justly divided into simple, inflammatory, and malignant; simple Fevers are the Effects of a Disturbance and Breach of the natural Order of the Blood, and a deprav’d Disposition of the animal Spirits, proceeding from an immoderate and irregular Exaltation of the sulphurous or fiery Ingredients in its Composition. Inflammatory are such, as are attended ordinarily with painful Swellings or Eruptions in the solid Parts, when the active Principles of the Blood, by a vigorous Effort, not only resist the Progress of the Fever, but wholly or in part, disengage the Matter of it, and breaking off its Complication force it to lodge in the solid Parts either external or internal…. A malignant Fever, the third Species above-mentioned, does not only by the excessive Power and licentious Encroachments of the fiery Particles upon the other Principles, break the Order and Oeconomy of Nature, in which a healthful State or Constitution is funded, but causes likewise that Disunion and Ruin of some parts of the Blood, in which Corruption, or Putrefaction does consist. And this is the essential Difference, that constitutes and distinguishes this from all Fevers of another Nature and Denomination….’
As his discussion makes clear, the dominant theory of causation for Blackmore was still humoral, but, as Sigal (1978) has pointed out, William Harvey’s theory of the circulation of the blood had issued a challenge to humoral based medicine. Other writers in Worth’s collection of fever texts took up this challenge and foremost among them was Thomas Willis (1621-75), an iatrochemist who sought to highlight the role chemistry might play in the treatment of disease.
Thomas Willis, Diatribæ duæ medico-philosophicæ (London, 1659), title page.
For Willis, causation was based on a theory of fermentation of the blood, one natural, the other ‘preternatural’. Dividing fevers into ‘intermittent fevers’, ‘continual fevers’ and ‘malignant fevers’, he advocated a host of different treatments, predominantly of a chemical nature. Later commentators (also collected by Worth), such as George Cheyne (1671–1743), adopted a more mechanistic approach, strongly influenced by the works of Giovanni Alfonso Borelli (1608-1679) and Lorenzo Bellini (1643-1704), authors whose works were likewise collected by Worth.
Selected Reading
Sigal, S. L. (1978), ‘Fever Theory in the Seventeenth Century: Building Toward a Comprehensive Physiology’, The Yale Journal of Biology and Medicine 51, pp 571-82.
Smith, D. C, ‘Medical Science, Medical Practice, and the emerging concept of typhus in mid-eighteenth-Britain’, in Bynum, W.F. and Nutton, V (eds) (1981), Theories of Fever from Antiquity to the Enlightenment (London, Wellcome Institute for the History of Medicine Medical History, Supplement No. 1), pp 121-134.
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