CONGENITAL DEAFNESS AS AN INCREASING OR DECREASING PHENOMENON
The final matter to be ascertained in respect to congenital deafness is whether it is relatively increasing or decreasing. The following table will show the number of the congenitally deaf in the censuses of 1880, 1890, and 1900, with their respective percentages and the ratios per million of population.[59]
NUMBER OF THE CONGENITALLY DEAF IN 1880, 1890, AND 1900
RATIO PER TOTAL CONGENITALLY PER MILLION OF NUMBER DEAF CENT POPULATION
1880 33,878 12,155 35.6 242 1890 40,562 16,866 41.2 269 1900 37,426 12,609 33.7 166
From this it appears that congenital deafness is decreasing both in relation to all deafness, and to the general population.
For further statistics, we may revert to our tables under advent.i.tious deafness. In the tables relating to periods of successive recent years we find in respect to three schools, the New York and Western Pennsylvania inst.i.tutions and the Maryland School, with certain fluctuations, no great change on the whole, though the last named school shows still a very high proportion. In two schools, the Michigan and Wisconsin, rather an increase is observed. In the Pennsylvania Inst.i.tution, which covers a period of seventy years, there is a decrease from over 50 per cent to less than 40.
A better test perhaps lies in the comparison of the proportions found for congenital deafness in the tables relating to periods widely separated in time. In these an increase is seen in the single case of the Ohio School; while a decrease is apparent in three, namely, the American and Iowa schools and the New York Inst.i.tution. These decreases in percentages are respectively from 44.8 and 50.1 to 35.2; from 37.2 to 26.9; and from 42.9 to 38.0.[60]
From the evidence that we have, then, taken together, it seems reasonable to conclude that congenital deafness is, though slowly, becoming less in the course of the years.
CONCLUSIONS WITH RESPECT TO THE ELIMINATION OR PREVENTION OF DEAFNESS
Most of what has been said in this chapter with respect to the elimination or prevention of deafness may be summed up as follows:
1. There are two kinds of deafness--advent.i.tious and congenital. Of the total number of cases advent.i.tious deafness comprises nearly two-thirds, and congenital deafness a little over one-third.
2. Nearly all advent.i.tious deafness is caused by some disease of infancy or childhood attacking the middle or internal ear, a large part being of infectious character. The two chief diseases causing such deafness are scarlet fever and meningitis, with a less amount from brain fever, typhoid fever, measles, catarrh, diphtheria, whooping cough, etc.
3. A considerable part of this deafness is preventable under enlightened action. Medical science is princ.i.p.ally in control of the situation, but there is also much that can be done in general measures for the protection of the health. In attacking the problem, the most immediate practical program lies in the arrest of those diseases, especially infantile and infectious diseases, that cause deafness.
4. Our evidence is incomplete to determine definitely whether advent.i.tious deafness is increasing or decreasing relatively among the population; but it is hardly other than likely that it is decreasing.
Although certain diseases producing deafness fail to show any extensive signs of abatement, there are other diseases from which there can be little doubt that deafness is decreasing.
5. In the outlook there is, on the whole, promise, both in respect to the treatment of deafness itself and of the diseases that lead to deafness, though it cannot be said in any sense that any large or general relief is at present in sight.
6. Of congenital deafness nearly half occurs in families often without any positively known strain to indicate a predisposition to deafness.
Though concerning this deafness little in the present state of our knowledge can be predicated, it is likely that with measures to secure a race sound in all particulars there will be a reduction to a greater or less extent of such deafness.
7. Consanguineous marriages do not take place, so far as deafness as an effect is concerned, to any great extent; though where they do the consequences are very marked. Their relation to deafness consists apparently for the greatest part in the fact that the chances of its transmission are thereby intensified, there being also a very strong connection with the question of deaf relatives in general.
8. There are a certain number of families in society deeply tainted with deafness, in evidence both lineally and collaterally, and this deafness may be transmitted from parent to offspring.
9. Children of deaf parents are far more likely to be deaf than children of hearing parents.
10. The great majority of the children of deaf parents, however, are able to hear, the proportion of those who are not being small.
11. The likelihood of deaf offspring is not necessarily greater when both parents are deaf than when one is deaf and the other hearing.
12. The liability to deaf offspring depends in the greatest degree upon the presence or absence in the parents, deaf or hearing, of deaf relatives, and, to a less extent, upon whether or not the existing deafness is congenital--being especially great under a combination of these two conditions.
13. Action in respect to marriages of the deaf likely to result in deaf offspring seems for the present rather to be limited to moral forces.
14. Congenital deafness appears, from all the evidence, to be decreasing relatively among the population, though probably only at a very slow rate.
15. Finally, with respect to our original inquiry, it is to be said that there are no indications that deafness will disappear from the human race within any time which we can measure; and hence that the deaf are to be in society not only for a season, but for a period apparently as yet indefinite. Nevertheless the situation is not without encouragement.
From the data in our possession regarding deafness as a whole, it seems certain that deafness is not on the increase relatively among the population. From our knowledge concerning advent.i.tious deafness, the probabilities are that, if anything, it is decreasing; while the evidence as to congenital deafness is that it is decreasing. It is likely, then, that deafness in general is tending to decrease; and we are thus justified in believing that the number of the deaf will in time become less.
FOOTNOTES:
[15] Moreover, later censuses are probably taken more thoroughly than former, with a consequent discovery of a larger number of the deaf; while at the same time greater care is employed in preparing the later censuses, with the more rigorous elimination of doubtful cases, all in some measure, however, tending to even up the differences. On the difficulty of making comparisons of the censuses of the deaf, see Special Reports, pp. 66-69; _Annals_, li., 1906, p. 487.
[16] _Ibid._
[17] Deafness has also been divided into three cla.s.ses: advent.i.tious deafness, congenital or hereditary deafness, and infantile or sporadic congenital deafness, the last cla.s.s including many cases where there are other antecedent defects, mental or physical, or where the deafness occurred shortly after birth with the exact cause not definitely determined. See Proceedings of International Otological Congress, ix., 1913, p. 49; _Volta Review_, xiv., 1912, p. 348; xv., 1913, p. 209.
[18] Of the cases usually ascribed to accidents, as falls, blows and the like, the probabilities are that a large part are really to be attributed to some other cause. Deafness is not often likely to result from such occurrences.
[19] See Proceedings of International Otological Congress, ix., 1913, p.
49; _Volta Review_, xiv., 1912, p. 348.
[20] Special Reports, pp. 110, 122, 124. See also _Annals_, x.x.xiii., 1888, p. 199; lii., 1907, p. 168. In the table are given only the specified causes that represent at least 0.7 per cent of the total amount of deafness. In respect to external ear trouble, impacted cerumen is usually found to result from water in the ear, or wax in the ear.
Other diseases of the middle ear of suppurative character are diphtheria, pneumonia, erysipelas, smallpox, tonsilitis, teething, bronchitis, and consumption. Other non-suppurative diseases of the middle ear are whooping cough, scrofula, exposure and cold, disease of the throat, thickening of eardrum, croup, etc. Of the internal ear, other causes affecting the labyrinth are malformation, noise and concussion, mumps, and syphilis; affecting the nerve, paralysis, convulsions, sunstroke, congestion of brain, and disease of nervous system; and affecting brain center, hydrocephalus and epilepsy. Among uncla.s.sified causes are also adduced neuralgia, childbirth, accident, medicine, heat, rheumatism, head-ache, fright or shock, overwork, lightning, diarrhea, chicken-pox, operation, and other causes.
[21] Proceedings of National Conference of Charities and Corrections, 1906, p. 250; Ceremonies of Laying of Corner Stone of Rhode Island School, 1907, p. 27.
[22] There are no general or organized movements on foot for the prevention of deafness as there are for the prevention of blindness.
This is perhaps chiefly because there are believed to be nothing like so many preventable cases of the one as of the other, so much of blindness being due to diseases that might have been avoided without great difficulty, and to accidents and other injuries to the eye.
[23] It has been estimated that three-fourths of deafness from primary ear diseases, and one-half from infectious diseases, is preventable. See Proceedings of International Otological Congress, _loc. cit._; _Volta Review_, xiv., 1912, pp. 251, 348.
[24] Proceedings, 1903, p. 1036.
[25] _Volta Review_, xv., 1913, p. 136. See also _ibid._, v., 1903, p.
415; _Outlook_, civ., 1913, p. 997.
[26] See _Medical and Surgical Monitor_, vii., 1904, p. 47; _New York Medical Journal_, lx.x.xiii., 1906, p. 816; _Annals_, lv., 1910, p. 192; _Volta Review_, xiii., 1911, p. 332.
[27] The possibilities, for instance, in the use of ant.i.toxins and vaccines in certain diseases are just beginning to be known, and some results as affect deafness may be expected from such operations.
[28] In 1909 a special committee in regard to the prevention of deafness was created by the Otological Section of the American Medical a.s.sociation, and in 1910 both by the American Laryngological, Rhinological and Otological Society and by the American Otological Society. See _Laryngoscope_, xx., 1910, pp. 596-665; _Volta Review_, xii., 1910, pp. 267, 545.
[29] Laws, 1906, ch. 502.
[30] On the possibilities of the prevention of advent.i.tious deafness, see Dr. J. K. Love, "Deaf-Mutism", 1896; Archives of Otology, xxiv., 1895, p. 50; _Journal of American Medical a.s.sociation_, liii., 1909, p.
89; _New York Medical Journal_, l., 1889, p. 205; lx.x.xix., 1909, p.
1007; xcv., 1912, p. 1189; _New York State Journal of Medicine_, xii., 1912, p. 690ff.; _Maryland Medical Journal_, lv., 1912, p. 33; _Pediatrics_, xxiv., 1912, p. 335; _Popular Science Monthly_, xlii., 1892, p. 211; "Progress in Amelioration of Certain Forms of Deafness and Impaired Hearing," Proceedings of American a.s.sociation to Promote the Teaching of Speech to the Deaf, iv., 1894; _Annals_, x.x.xiv., 1889, p.
199; lvi., 1911, p. 211; lviii., 1913, p. 131; _Volta Review_, xii., 1910, p. 143; xv., 1913, p. 303; New York _Times_, April 6, 1913; Public School Health Bulletin, Eyes and Ears, by Superintendent of Public Instruction of North Carolina, 1910.