22 



THE^ HISTORY OF TROPICAL MEDICINE 



now being rescued from this position thanks to the labours of 

 Manson, Blanchard, Bollinger, Eyre, Carter, Vincent, Nocard, Pinoy, 

 and Brumpt. 



Bacteriology. — From the most remote times the suspicion that 

 the mysterious cause of contagious and epidemic diseases must be 

 sought in living entities has flashed through the minds of many 

 observers. Columella, a contemporary of Seneca, records the belief, 

 apparently popular in his time, of the living nature of miasmata 

 and contagion. The idea of a contagium vivum was not extinguished 

 even in the darkness of the Middle Ages. Thus, for instance, in a 

 book written in the twelfth century, and wrongly stated to be by 

 St. Hildegard, the abbess of a convent, we find notices of minute 

 animals which produce disease. 



Fracastoro's sixteenth -century work is considered above, while 

 in 1641 Athanasius Kircher, a friar, stated that he had observed 

 minute living organisms in the blood of a patient during an epidemic 

 of plague. Linnaeus supported the theory that disease was due to 

 minute forms of life by inserting papers on the subject in his 

 ' Amoenitates Academicse.' But the first to promulgate scientifi- 

 cally a bacterial theory was Agostino Bassi, a country practitioner 

 of the north of Italy in the early nineteenth century. At that time 

 a peculiar disease was destroying the silkworms, bringing ruin to 

 the country in which the silk industry was paramount. Bassi, by 

 means of the microscope, discovered the germ which is the cause 

 of the disease. The organism received later the name of Botrytis 

 bassiana. From analogy, Bassi believed and stated that human 

 diseases were also due to micro-organisms. Bassi's work was not 

 appreciated by his contemporaries. 



In 1849 Pollender, and in 1850 Davaine, noted the Bacillus 

 anthracis in the blood of sheep suffering from anthrax, but it was 

 not until Pasteur, in 1857, had shown that fermentation was due to 

 a yeast and that butyric acid fermentation was due to a bacillus, 

 that Davaine, in 1863, considered that the rodlets which he had 

 seen in the sheep's blood were the cause of the disease. 



In 1882 Koch discovered the tubercle bacillus, and from 1877 

 to 1 91 1 he introduced and improved methods for the separation 

 and pure culture of bacteria, and laid down the proofs required to 

 demonstrate that a given bacterium is the cause of a disease; and 

 acting on these lines, Hansen in 1879 discovered the so-called 

 bacillus of leprosy, Eberth in i88a that of typhoid fever, Nicolaire 

 in 1884 that of tetanus, Koch in 1884 that of cholera, Bruce in 1886 

 that of Malta fever, Yersin and Kitasato in 1894 that of plague, 

 Shiga in 1898 and Kruse in 1900 that of bacillary dysentery. 



The discovery of the typhoid, paratyphoid, and allied organisms 

 has been of importance in enabling the differentiation of fevers 

 previously massed together into a chaotic group labelled 'malaria.' 



Serums and Vaccines. — The discovery of the immune serums, and 

 their application to the treatment of disease, marked a great step 

 forward in the history of medical science. 



