Mosquitoes and Malaria 187 



"it has been officially estimated to cause a mean annual death-rate 

 of five per thousand ; that is, to kill every year, on the average, one 

 million one htmdred and thirty thousand." In the United States 

 it is widespread and though being restricted as the country develops, 

 it still causes enormous losses." During the year 19 11, "in Alabama 

 alone there were seventy thousand cases and seven hundred and 

 seventy deaths." The weakening effects of the disease, the invasion 

 of other diseases due to the attacks of malaria, are among the very 

 serious results, but they cannot be estimated. 



Not only is there direct effect on man, but the disease has been one 

 of the greatest factors in retarding the development of certain regions. 

 Ever3rwhere pioneers have had to face it, and the most fertile regions 

 have, in many instances been those most fully dominated by it. 

 Herrick (1903) has presented an interesting study of its effects on 

 the development of the southern United States and has shown that 

 some parts, which are among the most fertile in the world, are 

 rendered practically uninhabitable by the ravages of malaria. How- 

 ard (1909) estimates that the annual money loss from the disease 

 in the United States is not less than $100,000,000. 



It was formerly supposed that the disease was due to a miasm, 

 to a noxious effluvia, or infectious matter rising in the air from 

 swamps. In other words its cause was, as the name indicated 

 "mal aria," and the deep seated fear of night air is based largely on 

 the belief that this miasm was given off at night. Its production 

 was thought to be favored by stirring of the soil, dredging operations 

 and the like. 



The idea of some intimate connection between malaria and 

 mosquitoes is not a new one. According to Manson, Lancisi noted 

 that in some parts of Italy the peasants for centuries have believed 

 that malaria is produced by the bite of mosquitoes. Celli states 

 that one not rarely hears from such peasants the statement that 

 "In such a place, there is much fever, because it is fuU of mosquitoes." 

 Koch points out that in German East Africa the natives call malaria 

 and the mosquito by the same name, Mbu. The opinion was not 

 lacking support from medical men. Celli quotes passages from the 

 writings of the Italian physician, Lancisi, which indicate that he 

 favored the view in 17 17. 



Dr. Josiah Nott is almost universally credited with having sup- 

 ported the theory, in 1848, but as we have already pointed out 

 his work has been misinterpreted. The statements of Beauperthuy, 

 (1853) were more explicit. 



