CHOLERA 177 



it is not endemic, its course may be traced along the 

 ordinary lines of traffic, showing that it is imported by 

 travellers. The recently-issued report of the Medical 

 Officer of the Local Government Board (' Cholera in Eng- 

 land,' 1893) shows how perfectly the disease may be 

 excluded from a country by the careful execution of strin- 

 gent regulations to prevent the landing of persons suffering 

 from the disease, or coming from infected ports without 

 undergoing due quarantine and disinfection. The season 

 of the year has great influence on the spread of cholera, 

 and if infection does not reach us till the cold weather is 

 about to set in, it is improbable that very much harm will 

 be done, though isolated sporadic cases may occur during 

 winter. 



Cholera spreads most rapidly when the earth tempera- 

 ture is high ; this happens chiefly when the ground- water 

 is low, and this is in accord with the observations of 

 Pettenkofer that increase in cholera is often preceded by 

 a fall in the ground- water. 



Transmission of the disease may take place by means 

 of water (as at Hamburg), by milk, uncooked vegetables, 

 or by fomites. Like enteric fever, , the infection is con- 

 fined to the bowel and stomach discharges; so that if 

 reasonable care be taken, there is but little fear of the 

 disease being transmitted from the patient to nurses or 

 attendants. 



The ' comma ' is readily capable of a saprophytic exist- 

 ence ; and thus, if cholera- stools were thrown out on to 

 a rubbish -heap without being properly disinfected, the 

 organism might live in such a position for a considerable 

 length of time. If this happens, it is probable that by 

 the action of rain the organisms will find their way into 

 any well near which has its supply from the surface-water ; 

 or should the pollution occur to a stream near the intake 



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