HISTORY, GEOGRAPHY, AND EPIDEMIOLOGY 1803 



valent in India, spreading again from Bombay to Arabia in 1851, 

 and to Turkey in 1853 ; while it also again travelled via Persia to 

 Russia in 1852, and so over Europe. This epidemic lasted till 1857, 

 and affected the troops engaged in the Crimean War. 



The fourth extensive epidemic began in 1863, and spread to 

 Europe by the two usual routes — viz., via Persia and Arabia — and 

 lasted till 1875, extending as usual to America. 



The fifth epidemic began in 1879, when the disease passed from 

 Mecca to Egypt, and so to Europe. It was during this epidemic 

 that Koch discovered the Vibrio cholem in Egypt in 1883. 



The sixth epidemic (1891-96) appears to owe its origin in India 

 to the great bathing festival at Karagola, on the Ganges, which, 

 being only held once in thirty years, came as a surprise to the 

 officials, who were not prepared for it. Cholera broke out among 

 the pilgrims on February 8, 1891, and spread rapidly, reaching 

 Europe in 1892. 



The seventh epidemic began in 1900, and may be said to be con- 

 tinuing at the present time. It started in 1900 in India after a 

 severe famine, and spread extensively through that country, and 

 then began to travel, reaching Japan in 1901 ; Arabia, Mecca and 

 Jeddah, Egypt and Erythraea, Syria, Persia, and the Philippines 

 in 1902; Palestine, Asia Minor, and Mesopotamia in 1903; Persia, 

 Russia, and Turkey in Asia in 1904; Russia, Germany, and the 

 Philippine Islands in 1905; Russia (few cases), Burma, Siam, 

 Singapore, Japan, China, and the Philippine Islands in 1906; Ceylon, 

 Peshawar, Singapore, Philippines, Japan, Korea, Manchuria, China, 

 Russia, Turkey, and Persia in 1907; China, Russia, Mecca, and 

 Medina in 1908; and Russia in the beginning of 1909. In 1910 it 

 was present in Russia and Italy. In 191 1 it was recognized in 

 Turkey, Roumania, Hungary, Austria, Italy, and Russia, and in 

 1912 in Turkey, Italy, and Russia. 



In 1914 the Dutch East Indies were attacked, and during the 

 war the Austrian Army and civil population were attacked, 

 especially in Galicia, as well as Bulgaria and Greece, while Turkey 

 has also suffered. In 1915 Brcka, in Northern Bosnia, was infected. 



Some places have always so far escaped the visitation of cholera. 

 These are either situated in the colder regions, of which the climatic 

 conditions are unsuitable for the propagation of the disease, or are 

 islands to which the disease is less likely to be brought, or where 

 precautions are taken. As examples of these islands may be men- 

 tioned the Andaman and Pacific Islands, Reunion, the Azores, etc. 

 Tropical and Southern Africa have not yet been infected. 



The climatic influences which appear to favour the development 

 of the disease are low-lying areas, and soils easily permeable to 

 water, especially if they are polluted with decomposing matter. 

 It would, however, appear that the most inimical chmatic condi- 

 tions can be overcome if there is lack of cleanliness, especially with 

 regard to drinking-water and food, together with bad sanitation, 

 and the disease may spread where every climatic influence is 



