E. histolytica: prevention and control 



mission by association has already been mentioned (p. 

 79) ; this apparently often occurs in families, a member 

 who is a carrier by uncleanly habits contaminating the 

 food, drinking water, towels, wash bowl, etc. The danger 

 from uncooked vegetables is especially great in countries 

 such as China where night soil is used as fertiHzer. 

 Recently Mills, Bartlett and Kessel (1925) have con- 

 cluded from their experiments that "Dipping fruits and 

 vegetables for 10 seconds in boiling water, or water 

 which remains above 80° C. during the immersion, is 

 the only method thus far discovered, which will uni- 

 formly kill all pathogenic bacteria, protozoan cysts, and 

 helminth eggs which might be found contaminating such 

 food products, and render them safe for human con- 

 sumption in an uncooked condition." Protection might 

 also be secured by a favorable diet. For example, Kessel 

 and K'e-Kang (1926) find that an exclusive diet of raw 

 milk always brings about a reduction in the number of 

 specimens present in the intestine of the host and in 

 certain cases entire freedom from the amoebae resulted. 

 The protection of communities. Community efforts for 

 the prevention and control of amoebic infection should 

 be directed primarily toward improvements in water sup- 

 plies, and general sanitation. An excellent example of 

 community protection by the provision of a pure water 

 supply is afforded by statistics from Panama given by 

 Clark (1924). Adequate water systems were installed in 

 Panama in 1914-1915. During the period from 1905- 

 1914, 170 cases of amoebiasis (4.25 per cent) were noted 

 among 4,000 autopsies, whereas from 19 14 to 1923 only 

 16 cases (0.57 per cent) were recorded among 2,800 



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