EXOTIC DISEASES 5 



The importance of the study of parasites in connection with 

 human disease to every community in the world is becoming 

 more and more obvious, even to those relatively free from para- 

 sitic diseases. There are those who think that such diseases 

 as kala-azar, sleeping sickness, Oriental fluke infections and 

 many other local or " tropical " diseases are of no vital im- 

 portance except to inhabitants of the countries directly influ- 

 enced or to travelers through these countries. That the im- 

 portance of such parasitic diseases is far greater than this is 

 obvious from the fact that, with modern facilities for com- 

 munication and with the extent of foreign immigration at the 

 present time, there is no part of the world so remote that the 

 things which affect it may not also affect any other part of 

 the world if conditions are suitable. 



There is probably no common exotic infection which is not 

 repeatedly brought into the United States through immigration 

 ports, especially in ports where the most thorough medical in- 

 spection of immigrants is not made. In the port of San Fran- 

 cisco alone over 50 per cent of 6428 Orientals whose faeces were 

 examined in the course of a little over two years were infected 

 with hookworms, each one capable of starting a new center of 

 infection in a previously free community. According to Dr. 

 Billings of the U. S. Immigration Service, during the " Hindu 

 Invasion" of the Pacific Coast of the United States in 1911, 

 about 90 per cent of all arriving Hindus were found to be in- 

 fected with hookworms. It is unfortunate that even at the 

 present time a considerable proportion of arriving Orientals 

 cannot, under the immigration law, be subjected to medical 

 examination. 



The possibility or probability of other diseases becoming 

 established in places not before troubled by them is a subject 

 of vital importance to any community or nation. Some of them 

 have already become established in places which were formerly 

 free. The fact that acquaintance with these exotic diseases is 

 lacking in the new territory, their nature not understood, means 

 of curing them unfamiliar, and means of prevention of spread 

 unknown, often results in much needless suffering and loss of 

 life. Furthermore, many infections are much wider in distri- 

 bution than has formerly been supposed. To cite one example, 

 amebic dysentery, and liver abscess which is often the sequel to 



