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TROPICAL DISEASES 



With regard to Northern Mexico, Ales Hrdlicka made six expeditions in 

 the years 1898-1905 to study the physiological and medical conditions of the 

 Amerinds residing in Northern Mexico and in the south-western portions of 

 the United States. 



He concludes that on the whole the health of these people is superior to 

 that of whites living in larger communities, as they do not suffer so much from 

 inherited morbid conditions, or from those connected with teething, puberty, 

 menstruation, gestation, puerperium, menopause, and senility, nor do they 

 suffer so much from malignant growths, but they have a weak resistance to a 

 few contagions^ — e.g., smallpox. 



Their most common ailments are diseases of the gastro-intestinal tract, 

 especially dysentery; of the respiratory organs, especially pneumonia, while 

 consumption is very rare; of the eyes, especially ophthalmia due to dust, 

 which, being neglected, leads to blindness, as does smallpox; of muscular 

 rheumatism and arthritis. Malaria, smallpox, and pemphigus contagiosus 

 in children are very common. Typhoid fever appears to be rare; leprosy and 

 elephantiasis are known, as is goitre. 



He very much doubts the presence of syphilis prior to Columbus, and points 

 out that the bones in the ancient graves in California, on the north-west coast, 

 in Peru, and other localities in South America, do not show any signs of the 

 disease, even when thorough examinations of extensive osteological collections 

 have been made. 



In children the common cause of death is diarrhoea. He makes most 

 interesting observations on the mites which burrow under the skin of the toes 

 in the Huastec, who live to the east of the Otomi (Hidalgo region), and which 

 may cause suppuration and even loss of a toe. Injuries due to spiders, centi- 

 pedes, scorpions, rattlesnakes, and the gila monster are mentioned, as well as 

 poisoning from aconite, datura, and fungi. The narcotic effects of Peyote are 

 noted, while two plants, cul-ick-um-ek {Donedia suffrutescens) and ha-van 

 tatat {Phacelia infundihuliformis), cause dangerous wounds when journeying 

 through forests, leading to some form of poisoning, and in the case of the 

 former even to death. He met with albinism and leucoderma, but pinta was 

 unknown, though stated to occur farther south. The diseases which were 

 rare were: anaemia, diseases of breast, circulatory organs, liver, female genera- 

 tive organs, and skin; while asthma, dental caries, cancer, rickets, hernia, 

 idioc5^ insanity, nervous diseases except epilepsy, scarlet fever, and fracture 

 of bones were also rare. 



With regard to the Virgin Islands, B:tler and Hakansson have pointed 

 out that malignant tertian and quartan malarias are present, but that the 

 carrier anopheline has not been identified, while pellagra is quite common and 

 ankylostomiasis is present. The lack of sanitation causes considerable 

 morbidity and mortality, and there is a high illegitimacy rate, venereal disease 

 rate, and infantile m.ortality, while the poor food conditions are held to be the 

 cause of pellagra, and the poor sewage disposal and defective water-supplies 

 to encourage diarrhoea, dysentery, enteric fevers, and the encouragement of 

 mosquitoes to breed in houses causes the high filarial infection and its associate 

 morbidity. 



Ecuador has been studied by Espinosa-Tamayo, who finds Ancylostoma 

 duodenale and Necator americanus present, as well as O'xyuris, TcBiiia solium, 

 and Hymenolepis nana. The jigger is noted and so is Xenopsylla cheopis and 

 Clinocoris rotundatus. Yellow fever has almost disappeared, but malaria, 

 amoebic dysentery, enteric fevers, and tuberculosis, are rife. Chichismos 

 caused by drinking ' chicha ' made from fermenting maize is said to be like 

 pellagra. 



Tropical Africa. 



The outstanding features of tropical Africa are its trypanosomiases, its 

 malarias, and its relapsing fevers; while enteric fevers and typhus are more 

 prevalent in the north, where the schistosomiasis and pellagra also abound. 

 Porocephalosis is likewise a feature of this country, which is the home of 

 numerous local diseases, such as guondou, while skin complaints are extremely 

 common. 



