PROC. ENT. SOC. WASH., VOL. 20, NO. 5, MAY, 1918 99 



at medical entomology with regard to its part in the war I shall di- 

 vide this portion of my discussion under five postulates. 



Insects are Important Disease Carriers 



At first thought we all recognize the fact that insects do carry 

 some diseases, and that they are the only known carriers of a few 

 diseases like malaria, and yellow fever. But most of us would 

 possibly be unwilling to commit ourselves very deeply as to how 

 many diseases insects do carry. As a matter of fact I am afraid^ 

 that even where we recognize that insects may have a role, the 

 tendency is to largely discredit it and minimize their importance. 

 Now if you will take a list of all the communicable diseases and 

 check off all those which are exclusively insect transmitted, and 

 those in which insect transmission has been shown possible, you 

 will be surprised at the small size of the remainder of the list. 



Furthermore the role of the insect is not confined to the trans- 

 mission of diseases. They are themselves the cause of many 

 ailments, some very serious. 



Let us just take a hurried glance at the list of proven insect 

 borne diseases. The following diseases of man can only be carried 

 by insects: malaria in all its types, yellow fever, dengue, the 

 relapsing fevers of Africa, America, Europe and Asia, typhus 

 fever, Rocky Mountain spotted fever, sleeping sicknesses, Chagas 

 disease, papatasi fever. 



The following diseases of animals can only be carried by insects: 

 avian malaria, pigeon anemia, canine anemia, Texas fever, red 

 \\ater, East Coast fever, various animal spirochaete diseases, 

 nagana, zousfana, and many trypanosome diseases, many animal 

 tape worms and nematodes. 



The following diseases of man are principally, if not entirely 

 carried by insects: trench fever, plague, tropical sore, Kala azar, 

 verruga, uta, and all other leishmaniases, and filariasis. 



The following diseases of animals are principally, if not entirely 

 carried by insects: murrina, anthrax, canine Kala azar, and 

 filariasis. 



The following human diseases are readily and possibly often 

 carried by insects: typhoid fever, dysentery, diarrhoea, anthrax, 

 tuberculosis, leprosy, hookworm, tapeworms, cholera, and tetanus. 



The following human diseases are frequently suspected of !> ing 

 insect transmitted: pellagra, beriberi, poleomyelitis, and infective 

 jaundice. 



The following diseases are the direct result of insect attack: 

 dermal, gastrointestinal and other myiases, tick paralysis, Tsutsu- 

 gamushi disease, scabies, dermatoses, poisoning by bites. 



Although these lists are large every one of them could be en- 

 larged from the manuscripts now on hand. 



