MOSQUITOES AND MALARIA. 11 



places is shorter and the infant mortality higher than in healthy 

 places. 



But, aside from this vitally important aspect of the subject, the 

 effect of malaria in lessening or destroying the productive capacity 

 of the individual is obviously of the utmost importance, and upon the 

 population of a malarious region is enormous, even under modern 

 conditions and in the United States. It has been suggested that the 

 depopulation of the once thickly settled Koman Campagna was clue to 

 the sudden introduction of malaria by the mercenaries of Scylla and 

 Marius. Celli, in 1900, states that owing to malaria about 5,000,000 

 acres of land in Italy remain — not uncultivated, but certainly very 

 imperfectly cultivated. Then also, in further example, in quite recent 

 years malaria entered and devastated the islands of Mauritius and 

 Reunion, practically destroying for a time the productiveness of these 

 rich colonies of Great Britain and France. 



Creighton, in his article on malaria in the Encyclopaedia Britannica, 

 states that this disease " has been estimated to produce one-half of the 

 entire mortality of the human race; and inasmuch as it is the most 

 frequent cause of sickness and death in those parts of the globe that 

 are most densely populated, the estimate may be taken as at least 

 rhetorically correct."** 



Is it possible to make any close estimate of the ratio between the 

 number of deaths from malaria and the number of cases of the same 

 malady ? No perfectly sound basis for such an estimate is apparent. 

 In the English translation of Celli's work on " Malaria According 

 to the New Researches," published in London in 1900, it is stated 

 that the mortality from malaria in Italy from 1887 to 1898 varied 

 from 21,033 in the first-named year to 11,378 in the last-named year, 

 and the mean mortality for the period is assumed to' be about 15,000. 

 In 1896 a count of the patients in the hospitals in Rome was made, 

 and the mortality rate of 7.75 per thousand of the actual patients was 

 established. Calculating then on this basis, and at this rate, the num- 

 ber of cases per year for Italy was placed at about 2,000,000. Accord- 

 ing to this estimate, and with the average mortalitj^ for the United 

 States of 12,000 as above indicated, the approximate number of 

 cases for the United States would be about 1,550,000. It seems obvi- 

 ous, however, that Celli, in using the basis of hospital patients only, 

 must have underestimated the number of cases for the Kingdom, 

 since of the people in the country suffering from malaria the propor- 

 tion entering the hospital must be relatively small. Therefore the 

 death rate from malaria of malarial patients in the hospital must be 

 greater than the death rate from malaria of the people who suffer 

 from this disease in the whole country. In fact, so great must this 



" See " Darwinism and Malaria," by R. G. Eccles, M. D., Medical Record, 

 iSfew Yorlt, January 16, 1909, pp. 85-93. 



