I CAN only refer very briefly to causes of leprosy other than those detailed in previous chapters. Next in importance to that of contagion is the question of heredity. The theory of heredity, as a factor in the propagation of leprosy, is rejected by leading authorities such as Hansen, Hjort, and Arning, and by many writers it is not even mentioned. Dr. Arning, while failing to discover evidence that the disease is congenital, is of opinion that a certain weakness to resist its attacks may be transmitted.

Dr. G. Armour Hansen, who discovered the bacillus leproe in 1873, has devoted much attention and research to the question of heredity, and failed to find a decided and indisputable proof of its influence in the United States, though hundreds of thousands of immigrants had leprous parents in Norway. — Minnesota State Board of Health Report, 1889-90, p. 43.

Dr. W. Munro says :—" I do not deny that leprosy may be occasionally hereditary, but only say that it has never been proved to be so."

Dealing with the subject of the alarming increase of leprosy in Hawaii, the victims amongst a clean nation multiplying faster as the years roll on, until it has invaded nearly every district in the Archipelago, Dr. W. Hillebrand observes :—" And, mark well, in all this, hereditary taint, from the nature of the case, has no share, or, if any, only a most subordinate one."—Leprosy a Communicable Disease, by Dr. Macnamara, p. 59.

The Lancet, March 3 1st, 1883, p. 555, observes "Morehead, as well as Lewis and Cunningham at Almora, came to the conclusion that heredity could not be a great factor in the increase of leprosy in a district, inasmuch as lepers have comparatively small families, who suffer a high rate of mortality, and therefore the survivors are only just numerous enough to replace their defunct progenitors."

Dr. George L. Fitch, in his report addressed to the president and members of the Board of Health, Honolulu, in 1884, says:—"Heredity plays but little figure in the spread of the disease, because we find that, after sending more than 2800 lepers, during a period of eighteen years, to Kalawao Leper Settlement, there are only twenty-six children alive, and only two of these children are lepers."—Appendix to Report on Leprosy in Hawaii, 1886, p. 31.

In a note to the Secretary of the State Board of Health,, Minnesota, U.S., December, 1888, Dr. Christian Gronvold observes:—" Our experience in the North-West has made it probable that the disease is not hereditary. Not a single case has been discovered, after forty years of immigration, where a child, born in these States of leprous parents, has inherited the disease."

The same authority concludes an article on "Leprosy in Minnesota" as follows:—" I cannot here relate all my observations in detail. I will only tell what I have found in regard to the occurrence, or rather the disappearance, of lepra in America (N.W. States). Of about 160 lepers who have immigrated into the three States named (Wisconsin, Iowa, Minnesota), thirteen are alive, whom I have seen myself, and perhaps three or four more. All the others are dead. Of all the descendants of lepers (and that includes the great-grandchildren of some of them), not a single one has become leprous. This is, in short, the result of my investigations."—Lancet, March 26, 1892.

Report of the Select Committee on the Spread of Leprosy, Cape of Good Hope, July 15, 1889. Minutes of Evidence:--

The Hon. Dr. Atherstone, M.L.C., who has practised in the Colony fifty years, chiefly in Graham’s Town, where he was District Surgeon for twenty-six years, and who has always taken a great interest in the subject, said, in answer to Q. 352 concerning heredity, that "it is the constitutional diathesis, or cachexia, which, I consider, is inherited; not the dormant germs rendering the individual less able to resist its attacks and subsequent reproduction."

In an article on the "Cause of Leprosy," by Sir William Moore, K.C.I.E., Hon. Physician to the Queen, late Surgeon-General with the Government of Bombay, the author says :—"We are told that leprosy is caused by eating fish, and, therefore, cannot possibly be syphilis. Now, I lived and worked many years among the inhabitants of the semi-desert districts of Western India, who never see fish. The sea is hundreds of miles away, and there are no lakes or rivers. Even dried fish did not penetrate into those remote districts. Fish was practically unknown as an article of diet. Yet there is a considerable amount of leprosy in those countries. At recent meet ings of the Medical and Physical Society of Bombay, the subject of leprosy was exhaustively discussed, and the members were unanimous in discrediting fish as a cause of leprosy. The members, being both native and European practitioners, private and in the public services, who are constantly seeing leprosy, are perhaps better qualified than any body of men to give an opinion on this matter. In the districts of Western India above referred to, salt is made from the earth at most villages. The people have as much salt as they want. Yet leprosy has been attributed to an absence of salt. It has always been ascribed to a vegetable diet, to new rice, and to diseased grain. But the kind of food does not appear to influence the disease further than, like insanitary conditions, insufficient food, and food deficient in required elements, that it induces a state of constitution rendering the subject more liable to almost any malady. Again, it has been advanced that leprosy is not, like syphilis, contagious. But the communication of leprosy has certainly been proved. Direct proof seems to have been afforded by the experiment on the criminal at Honolulu. In the case of Keanu, bacilli were found to have multiplied at the seat of inoculation……..Leprosy very frequently commences on the extremities. Natives in India do not generally wear shoes and stockings; their feet are thus very liable to become abraded or wounded; a leper’s slippers may easily be taken by mistake, and conveyance of discharge is, I believe, thus frequently accomplished."

In an article in the Fourth Annual Report of the State Board of Health for Massachusetts, U.S., by Dr. Samuel W. Abbott, reprinted in the Hawaiian "Report on Leprosy in Foreign Countries," 1886, is the following, under the title of "Leprosy in its Relation to Public Health ":—"The questions which render leprosy a matter of special interest, as affecting public health, are those of etiology, modes of propagation, and the question of contagion.

"The causes of leprosy have been sought for in the peculiarities of climate, soil, diet, and habits of life. As regards climate and soil, the wide geographical distribution of the disease would seem to preclude them as elements or factors of causation. Opinions differ much as to the question of diet. The eating of tainted fish has been strongly urged as a cause. Leprosy is found in a most aggravated form among fish-eating people, as in Norway and Crete, and, on the other hand, it also prevails in inland districts where fish is but little used.

"Doubtless an improper diet and bad hygienic surroundings aggravate the disease.

"All these causes acting together for centuries did not produce the disease in the Hawaiian Islands, nor was it known until some time after the islands were open to foreign trade and commerce with other nations."

Mr. Jonathan Hutchinson says :—" The suspicion that vaccination has been the means of spreading the disease in the case of the Sandwich Islands has been entertained." The spread of leprosy, according to this distinguished surgeon, is due to eating fish, a theory which finds very few supporters amongst those who have studied the disease in leprous countries. The Parsees are great consumers of fish, and leprosy amongst them is of rare occurrence. With regard to the fish theory, which has obtained currency owing to the eminence of its author, I may observe that in my travels in leprous countries I have hardly met with a single advocate of it, and those most practically conversant with the disease at leper institutions consider it both far-fetched and irrational. In an article on "Leprosy in Kashmir," by Dr. A. Mitra, Chief Medical Officer in that country, in the American Journal of Medical Sciences, Philadelphia, pp. 22 and 23, the author says :—"As to Hutchinson’s fish theory, the Goojurs do not get fish. Since this theory first came to my notice in the pages of the Lancet I have always asked lepers if they have been fish-eating, and in the large majority of instances the reply was in the negative. The theory is untenable in India, where we do not find the disease more prevalent among fish-eating people than among abstainers from such food, as vaisnabs. The Kashmiris, among whom leprosy is rare, eat fish, fresh, dried, and salted. In India European sportsmen, planters, etc., use largely preserved fish, but there are no facts to show that fish-eating ever produced leprosy, among them. High-class Hindu widows are strictly prohibited from taking fish, but I have seen several cases of leprosy among them. But the fact that the leprosy is common among Goojurs completely disproves the fish theory." In "Notes on Leprosy in Norway," Dr. Hercules MacDonnell observes :—" Nowhere did I perceive that any credence was attached to the fish-origin ‘theory. Dr. Kaurin’s writings on this special subject are widely known abroad."—Lancet, August31, 1889.

Dr. C. N. Macnamara says:—"Among the Norwegians putrid and dried fish are said to give rise to leprosy; others fancy that rice prepared in a particular way is at the root of the evil. We may be sure that the theory of bad and salted food being a cause of leprosy does not apply to many parts of India, for the natives, as a rule, do not eat salted food, and certainly are not in the habit of consuming putrid fish."— Leprosy a Communicable Disease, p. 48.

In a paper read before the New Brunswick Medical Society, July, 1889, by Dr. Murray MacLaren, M.R.C.S., on "Leprosy in New Brunswick," Mr. Jonathan Hutchinson’s Fish and Food theory is dealt with. After quoting Mr. Hutchinson, the writer says:—" This view is not at all borne out by what can be observed, in our own affected district, which is only 45 miles in length, and of the 82 cases already mentioned, 58 have arisen in the parish of Tracadie alone, which has been the headquarters of the disease, while the remainder come from the other parishes: Niguac, 3; Pokemonde, 9; Shippegan, 6; Caraquette, 6. It does not seem possible that this district, and especially Tracadie, should have food in any way different from a large part of the extensive northern and eastern coast, which is quite similar to the leprous district in soil, climate, food, including fish, and inhabited by a similar race of people’ with the same manners of life. Besides this, the fact that no case is known to have occurred among the Indians dwelling within the affected area helps to disprove this theory."— Maritime Medical News, July, 1890, p. 50.

Dr. Julius Goldschmidt, in a communication on "The Madeira Leprosy," says :—" Those districts where mostly fish is consumed, and sometimes in an unhealthy state (coast villages), are freer from the disease than in other parts of the island."—Journal of the Leprosy Investigation Committee, No. 4, December 1891.

Dr. Max Sandreczki, Director of the Children’s Hospital, Jerusalem, says :—"Leprosy in Palestine is developed by insanitary conditions, of which I will enumerate the chief: impure air; the tainted exhalations which prevail in the villages and unhealthy habitations of the fellaheen; the water supply, often stagnant and deteriorated; the oil and fat (used for food), rancid, or salted beyond measure; olives and cheese in a state of decomposition; meat rotten, or coming from animals diseased, or worse still. Add to all this extreme uncleanliness, the utter absence of skin action, and then one ‘may easily explain derangements in the tissues of the skin, in the lymphatic and ganglionic systems, and, in a word, complete disorder of all the nutritive functions."— The Lancet, August 31st, 1889. -

The Hon., David Dayton, President of the Board of Health, Honolulu, says :—" I am not of the opinion that leprosy ‘is always hereditary, so many cases proving to the contrary. By referring to tables in Mr. C. B. Reynolds’ reports, it will be seen that a large proportion of the girls in the Kapeolani Home were children of leprous parents without becoming diseased themselves."—Report, Board of Health, Honolulu, 1892, p. 42