ECONOMIC LOSS TO THE PEOPLE OF THE UNITED STATES 

 THROUGH INSECTS THAT CARRY DISEASE. 



INTRODTJCTION. 



It has been definitely proven and is now generally accepted that 

 malaria in its different forms is disseminated among the individuals 

 of the human species b}^ the mosquitoes of the genus Anoplieles, and 

 that the malarial organism gains entrance to the human system, so 

 far as known, only b}^ the bite of mosquitoes of this genus. It has 

 been proven with equal definiteness and has also become generally 

 accepted that yellow fever is disseminated by the bite of a mosquito 

 known as Stegomyia calopus (possibly by the bites of other mos- 

 quitoes of the same genus), and, so far as has been discovered, this 

 disease is disseminated only in this way. Further, it has been sci- 

 entifically demonstrated that the common house fly is an active agent 

 in the dissemination of typhoid fever, Asiatic cholera, and other 

 intestinal diseases hy carrying the causative organisms of these dis- 

 eases from the excreta of patients to the food supply of healthy indi- 

 viduals; and that certain species of fleas are the active agents in the 

 conveyance of bubonic plague. Moreover, the tropical disease known 

 as filariasis is transmitted by a species of mosquito. Furthermore, it 

 is known that the so-called " spotted fever " of the northern Rocky 

 Mountain region is carried by a species of tick; and it has been dem- 

 onstrated that certain blood diseases may be carried by several species 

 of biting insects. The purulent ophthalmia of the Nile basin is 

 carried by the house fly. A similar disease on the Fiji Islands is 

 conveyed by the same insect. Pink eye in the southern United States 

 is carried by minute flies of the genus Hippelates. The house fly 

 has been shown to be a minor factor in the spread of tuberculosis. 

 The bedbug has been connected with the dissemination of several dis- 

 eases. Certain biting flies carry the sleeping sickness in Africa. A 

 number of dangerous diseases of domestic animals are conveyed by 

 insects. The literature of the whole subject has grown enormously 

 during the past few years, and the economic loss to the human species 

 through these insects is tremendous. At the same time, this loss is 

 entirely unnecessary; the diseases in question can be controlled, and 

 the suppression of the conveying insects, so absolutely vital with 

 certain of these diseases and so imj^ortant in the others, can be brought 

 about. 



