286 FLIES AND DISEASE 



disease is a most important one in the regions in 

 which it occurs and is of particular interest because 

 it is caused by an ultra-microscopic organism. 

 Further the researches which elucidated its cause 

 and mode of transmission show how difficulties, 

 which at first appear insuperable, may be overcome, 

 and lastly the measures for the limitation of this 

 disease founded on these researches have been 

 attended with very remarkable results. 



The disease is widely distributed in tropical 

 and subtropical America, also, according to most 

 authorities, on the West Coast of Africa. In early 

 times it was believed that the virus was in some 

 way transmitted through the air, and later several 

 species of bacteria were described as the cause 

 of the disease. The disease was considered to 

 be highly contagious; patients suffering from it 

 were strictly isolated, and their clothing, etc. 

 thoroughly sterilized. In spite of the isolation of 

 patients, however, epidemics were not checked, and 

 it was noticed that many persons became infected 

 without ever having come into contact with cases, 

 whilst frequently doctors and nurses, who worked 

 in the same rooms as the patients, did not suffer 

 from it. Mosquitoes were suspected as early as 

 1848, but the cause and mode of infection remained 

 obscure until the disease was studied in Cuba by 

 an American Commission in 1899. 



The Commissioners first investigated the claims 

 made for various bacteria, and showed that none 



