manently. The main regions in which malaria is still 

 prevalent are Central, and much of South America, most 

 of Africa ( except the Republic of South Africa), parts of 

 Arabia, much of the Near East, India, China, and South- 

 East Asia. By 1961, of 1,420 milHon people (half the 

 world's population) exposed to malaria, 317 million were 

 freed of the threat, 710 million were involved in active 

 eradication programmes, 170 million were in areas planned 

 for attack soon, while 223 million were totally unprotected. 

 The eradication of malaria in any area takes about eight 

 years altogether: the first year is the preparatory phase; the 

 second to sixth years, the attack phase, involving total- 

 coverage spraying (interruption of transmission of the para- 

 site is achieved after about 2Vi years); and the sixth to 

 eighth years, the consolidation phase, in which only focal 

 spraying is necessary (the infection rate is reduced to only 1 

 person in 2,000 after about 5 years). After the eighth year, 

 the work comprises maintenance of freedom from malaria 

 by detection and treatment of every individual case of the 

 disease, and, if necessary, blood examination of the entire 

 population to locate any remaining malaria carriers. 



The elimination of malaria may also be assisted by the 

 issue of chloroquinine-medicated salt to all people living 

 in areas in which spraying is not completely effective. Ma- 

 laria should be eradicated from Europe in 1962, and from 

 the Americas, North Africa, and much of Asia within ten 

 years. But success in much of Africa is slow at present. 

 The degree to which so many nations, including the back- 

 ward ones, are collaborating in this great effort is indeed 

 encouraging to all who look forward to the same sort of 

 thing in other fields of scientific application for the benefit 

 of all people. 



A great achievement for science is the recognition by 



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