THE CRETIOTC DEGENERATION 443 



mountainous areas, for the disease flourishes in the plains of Lombardy, 

 Piedmont, Venice, Alsace. River and lake basins and deltas may likewise 

 be favored. Such are those of the Struma River in the Balkans, so named 

 from the prevalence of goiter on its banks (Crotti), the Lena and Obi in 

 Russia, the Ganges, Indus, Brahmaputra and other Indian rivers, the 

 Great Lakes and the St. Lawrence in America. Crotti mentions a river 

 in Brazil called the Guay-qui-mro or "Thick neck maker" on account of 

 its goitrigenous qualities. 



Several writers call attention to the prevalence of the disease in 

 marshy regions and inundated areas, along canals. If one bank of a river 

 is a marshy region, the other high land, the former will be affected (for 

 example, the Ganges). Islands may have endemic foci, even those such 

 as the Azores at great distance from other land. In Madagascar, Ceylon, 

 Borneo, Sumatra, Java, the disease is known. 



The sea coasts, though formerly claimed to be entirely free from goiter 

 and cretinism are occasionally affected. McCarrison quotes the following 

 endemic littoral regions, the Ganges delta, the Island of Cutch in Manila 

 Bay, the Island of Arran off the coast of Algeria, Glamorganshire, certain 

 shores of the Mediterranean, such as Istria and Dalmatia. 



Altitude bears no direct relationship to the presence of cretinic degen- 

 eration as it is found all the way from the sea level to the Himalayan 

 villages situated over 10,000 feet above sea level (McCarrison), or even 

 up to 15,000 feet in Nepal and Kashmir (Crotti). Foci of the disease 

 are frequently found half way up the sides of steep valleys and less often 

 on high tablelands. The association of endemic goiter and cretinism with 

 certain geologic strata has been the subject matter of so much speculation 

 that this subject, with other theories as to causation, is best treated under 

 the section "Etiology." 



Prevalence, Economic and Military Importance 



From point of numbers of inhabitants affected, cretinic degeneration is 

 one of the most common of all morbid conditions. In certain endemic 

 regions of Switzerland, Austria and India, it is to be regarded as the most 

 frequent of all diseases, for practically every inhabitant is more or less 

 affected. 



Its economic and military significance has become of great moment and 

 has led to the appointment, in England, France, Switzerland and Italy, of 

 commissions for the special study and research of its etiology and preven- 

 tion. So much data has been collected upon the matter of prevalence that 

 it has become unwieldy for detailed presentation. A few notations may 

 here suffice. 



In Switzerland about 3,000 recruits are annually rejected for causes 





