304 BRIEF HISTORY OF BACTERIOLOGY UP TO 1881 



CAUSATION OF DISEASE. 



The transmission of disease from person to person was 

 recognized by the ancients of European and Asiatic coun- 

 tries. Inoculation of smallpox was practiced in China and 

 India probably several thousand years ago and was intro- 

 duced by Lady Mary Wortley Montague into England in 

 1721 from Constantinople. These beliefs and practices do 

 not seem to have been associated with any speculations or 

 theories as to the cause of the disease. 



Apparently the first writer on this subject was Varo, about 

 B. c. 70, who suggested that fevers in swampy places were 

 due to invisible organisms. The treatment of wounds dur- 

 ing the thirteenth and fourteenth centuries by hot wine 

 fomentations and by the application of plasters was based 

 on the theory that the air brought about conditions in the 

 wounds which led to suppuration. These practices were 

 indeed primitive antisepsis, yet were not based on a germ 

 theory of the conditions which w^ere partially prevented. 



Fracastorius (1484-1553), in a work pubhshed in 1546, 

 elaborated a theory of 'disease germs" and "direct and 

 indirect contagion" very similar to modern views, though 

 based on no direct pathological knowledge. Nevertheless, 

 Kircher (mentioned already) is usually given undeserved 

 credit for the "contagium vivum" theory. In 1657, by the 

 use of simple lenses, he observed "worms" in decaying sub- 

 stances, in blood and in the pus from bubonic plague patients 

 (probably rouleaux of corpuscles in the blood, certainly not 

 bacteria in any case). Based on these observations and 

 possibly also on reading the work of Fracastorius, his theory 

 of a "living cause" for various diseases was published in 

 1671, but received little support. 



The discoveries of Leeuwenhoek, which proved the exist- 

 ence of microscopic organisms, soon revived the " contagium 

 vivum" idea of Kircher. Nicolas Andry in a work pub- 

 lished in 1701 upheld this view. Lancisi in 1718 advanced 

 the idea that "animalcules" were responsible for malaria, 

 a view not proved until Laveran discovered the malarial para- 



