148 MALARIA 



worm, are largely responsible for the present deplorable condition 

 of some parts of our own South. Dr. Howard estimated in 1907 

 that there were nearly 12,000 deaths a year in the United States 

 from malaria. This, however, is probably almost inconsiderable 

 when the amount of damaged health and weakened resistance to 

 other diseases is taken into consideration. Dr. Von Ezdorf, of the 

 U. S. Public Health Service, in a recent attempt to estimate the 

 prevalence of malaria in the United States, obtained data, based 

 on morbidity reports, which indicate that at least four per cent of 

 the population of eight southeastern states — 1,000,000 people 

 — is affected by the disease annually, and found by 13,526 blood 

 examinations that over 13 per cent harbored malarial parasites 

 in their blood, the percentage being much higher in negroes 

 than in whites. Dr. Howard thinks that an estimate of 3,000,000 

 cases of malaria a year in the United States would not be too 

 high. Millions of acres of fertile land in this country are rendered 

 useless or only imperfectly cultivable. Taking everything into 

 consideration, Dr. Howard makes the astounding but well- 

 founded statement that the annual financial loss to the United 

 States from malarial diseases is not less than $100,000,000. 

 This is the condition in the United States, a large portion of which 

 is relatively free from malaria, and in no part of which is the dis- 

 ease so prevalent or so destructive as in the tropical portions 

 of Asia, Africa and South and Central America. In a broad way 

 one-third of the population of highly malarial countries suffer from 

 the disease annually. According to Ross the number of deaths 

 from malaria in India must reach 1,300,000 every year. Obvi- 

 ously the importance of this disease to mankind is not likely to 

 be overestimated. 



History. — " Malaria " means bad air, and was therefore ap- 

 plied to a number of fevers which were commonly associated 

 with the bad air of swanipy regions. The idea that malaria is 

 caused by bad air, unwholesome odors, damp night winds, or 

 impure drinking water is even yet adhered to not only by some 

 of the populace but even by a few unenlightened medical men. 

 Ross says that it takes ten years for the world to grasp a new 

 idea, but his estimate is far too low; it is now (1917) 37 years 

 since the organism causing malaria was discovered and 19 years 

 since its transmission by mosquitoes was experimentally proved. 

 It was in 1880 that Laveran, a French army surgeon in Algeria, 



