Tropical is used here in the sense of locality more than to characterize any special type of neurasthenia. My object primarily is to call attention to its frequency in warm countries, at the same time touching somewhat on the disease as I have observed it.
Writers on tropical diseases make little or no mention of it. Dana, in his work on "Nervous Diseases," states that it is not infrequent in tropical regions and that it is found in the West Indies. My experience extends over six years' residence in Porto Rico, but information derived from various sources has caused me to regard this condition as one quite general to the tropics, differing in degree through peculiar local influences. From what I have been told by medical men who have resided in the Philippine Islands I judge that it is even more prevalent and more severe there than in the West
KING WW. TROPICAL NEURASTHENIA.. JAMA. 1906;XLVI(20):1518-1519. doi:10.1001/jama.1906.62510470032001j