OUTLINES OF THE HISTORY OF DIPHTHERIA IN

DENMARK.

BY J. CARLSEN. MD.

Privatdocent at the University of Copenhagen.

I.

Introduction. The relation between Croup and Diphtheria from a historical view. Diphtheria in Denmark.

W

e may hardly think it a mere accident that the idea of an international review including the Historical-Geographical Pathology now is coming up in the medical world and is realized by the publication of ,,Janus." The pathological Anatomy has had its suppremacy and has receded in favour of Bacteriology and experimental Pathology, which in all but two decennials has suppressed the other essential resources of General Aetiology. Should it be that the Historical-Geographical Pathology is developing itself to be such a support for the latter branch of science, which it tried in vain to be 30 or 40 years ago? Certain facts indicate that Bacteriology on several points has come to such bars as it cannot get over; that it is the study of the extra-laboratorical, occasional causes, the study of the disposition of man himself, that will have to push General Aetiology a step forward on the way to the conception of the pathological processes.

The aims of the Historical-Geographical Pathology are to give the varying appearances of the diseases at different times and in different countries, to remind the pathologist of the non-stability of the forms of many diseases (how often has the belief in the stability hindered the progress of science! did not Brétonneau believe, that his Diphtheritis always would present itself,,invariablement sous la même forme"?); the Historical-Geographical Pathology will point out several of the ways the bacteriological researches must take; for its own part it has to deal with a still greater num

ber of problems, whose solutions only can be obtained through medico-statistical experiments.

The Historical-Geographical Pathology is chiefly working comparatively; only few are the general truths which appear from studies of a single country and a bounded period. The conditions without which the Historical-Geographical Pathology cannot attain its object, are the following 1, The existence of a reliable material, from the different countries; 2, This material being formed so as to allow its international application, for which purpose is necessary, not only, that it shall appear in one of the great universal languages, but also a perfect explanation of its genesis and its value, of the meaning of the applied terms of diseases, of the specially local circumstances influencing upon the appearance of the disease, in short, a statement of all the facts preventing an international application of the material for further comparative researches, so that we may get rid of the so-called objective, that is to say uncritical, second-hand summaries, largely employed by the great periodical journals, in which the most unscientific hodge-podge often is placed at the side of solid scientific work. The foresaid essential conditions are well known to exist only to a slight degree. The extensive collective works (we need not mention the just published, most confused work by Lersch*) of Haeser, Lombard, Hirsch are not sufficient for a penetrating comparative study of the different diseases. The most read and the most accurate of these, the gigantic work of Hirsch is surely wanting a revision, what this treatise will prove as far as concerns one disease and a few countries. Nor is it doubtful that such collective works as comprise the histories of all diseases in all countries, will become ever more fragmentary, consequently ever less applicable to scientific use, as more countries by and by are entered into the domains of nosography, and as the material from the different countries as a consequence of the evolution of Statistics of mortality and morbidity is swelling out. It will be necessary for the future to discuss the single disease, as Newsholme has lately attempted in his fine treatise of Rheumatic fever*) comprising details from many countries. Each country, or each province of a country, ought to procure a completest possible historical description of each there apprearing disease, this is the great

problem of the future. An international periodical journal, as

1) Geschichte der Volksscuchen. Berlin 1896. 2) The Lancet. March. 9. 1895. p 589.

„Janus," will be able to offer an extraordinary support to the comparative application of those descriptions in yielding a gathering-place to such monographies; the thought of collective international investigations then will be realized in the right manner.

As a contribution to such a collection of documents concerning the histories of the different diseases in each country, the author of this treatise takes the liberty here to present statement of the history of Diphtheria in Denmark until this day; it will essentially apply to the periodical changes in the frequency of this disease, the author supposing that the first problem concerning this disease which the comparative Epidemiology will set to work with, will be to search for the cause of the great periodical changes represented in the appearance of Diphtheria, to investigate if those changor owing to meteorological influences operating over larger parts of the earth, or if they must be ascribed to periodical changes of the vitality of the Diphtheria-bacillus itself or to a periodical es are connected with wanderings of the disease from land to land, co-operation with other morbific organisms.

The following description of the history of Diphtheria in Denmark is partly an extract of, partly a supplement to a previous essay by the author 1), treating of Diphtheria in Denmark in the period until 1850. Wärn for Sweden 2), Johannesen for Norway 3), Neukomm for canton Zürich in Switzerland 4) have given complete description of the history of Diphtheria in the languages of the countries concerned. Of course, for the small nations it is easier to offer the contributions required by the comparative Epidemiology from each country.

Before proceeding to the proper object it will be necessary to give The relation between Croup and Diphtheria from a historical view. The ancient dissension as to the relation between Croup and Diphtheria is of small practical importance for the aetiology of Croup in our days, since it has been proved, that the Diphtheria-bacillus can be the cause of Croup, which in clinical and anatomical respect is quite identical with „Croup d'emblée" that is Croup without membraneous sore-throat. It may be, as hinted in a just published bacteriological treatise in a German medical journal that a genuine, that is non-diphtherical Croup may be found, but beyond any doubt

1) J. Carlsen. Bidrag til Difteriens Historie i Danmark og Tydskland Kjöbenhavn 1890. 2) Wärn: Om Difteriens och Strypsjukans Upträdende i Sverrige. Stockholm 1885. 3) A. Johannesen : Difteriens Forekomst i Norge. Christiania 1888. 4) Neukomm die epid. Diphtherie in Canton Zürich. Leipzig 1886.

almost all cases of primary, membraneous Laryngitis of the present time are of diphtherical nature, and the genuine Croup, if existing, is an extremely rare disease. But of eminent historical importance is the question of the nature of that Croup, which after the time of Home (1765) would appear, now sporadic, now epidemical, around in the different countries, especially at periods when, and at places where, diphtheritic sore-throat seemed to be unknown. Was that disease, as taught by Hirsch, the genuine Croup, a disease of childhood, preferring certain seasons, and certain countries, occasioned by meteorological causes (a cold), non-contagious, not properly epidemical, but appearing now and then with an accumulation of cases, as other catarrhal diseases? or was that disease a kind of unrecognised Diphtheria? Evidently a decisive answer cannot be given because the bacteriological diagnosis is excluded; still so many facts pointing in one particular direction may be produced that the choice between the two possibilities cannot be doubtful.

The most important of those facts is the inclination to periodical appearance distinguishing the Croup of the past. This periodicity has first been pointed out by Lombard, as regards the city of Geneve 1) but to the Scandinavian searchers: Wärn, Almquist 2) and Johannesen belongs the honour of having produced numerous examples of long Croup-periods and long Croup-free periods in Swedish and Norwegian localities and of having indicated the importance to be ascribed to this trait of the history of the disease with respect to the conception of the diphtheric nature of Croup. Wärn and Almquist have moreover put an end to the myth of the Croupendemia at Wenern that from the wellknown work of Hirsch has passed into all later Croup-monographics and — in connection with accounts of similar (may be artificially produced) endemies has supported the theory of the genuine Croup.

In the Danish Epidemiology are deposited experiences going in the same directions as those mentioned, concerning the periodicity of Croup.

In Jeeland Croup was rather frequent in the years 1820-27, afterwards almost quite disappearing until 1848. In the Faeroe-islands Croup has only appeared in periods when Diphtheria has reigned. Before 1857 the reports of the physicians state that this disease was unknown there; it made its appearance along with the diphtheric sore-throat, disappearing along with it after 1863, reappeared in 1875 when the next epidemic of diphtheria lasting until 1882 presented itself; during the next four years the physicians-besides sporadic cases of diphtheric sore-throat treated from 1-5 cases of Croup annually; during

1) Traité de climatologie méd. IV p. 401.

2) Ueber die Ausbreitungsweise v. Diphterie und Croup. Göteborg 1885,

the following 5 years no case of Croup and Diphtheria was found; in 1892 and following years diphtheric sore throat and Croup reappeared.

In the most northern district of Jutland, the district of Skagen the history of Croup is very instructive. In the years from 1812 (when the reports of medical officers are beginning) to 1844 nothing is heard of Croup; in 1845 mortal cases of Croup are recorded and in the following years until 1870 Croup and diphteritie sore-throat appear almost every year, some years epidemically, but most frequently sporadically; from 1871 to 1886 Croup was not found (1884, 1885, 1886 only a single case of dipheritic sore-throat is noted). In the years 1887-94 we again find either forms of the disease, which disappear in 1895 and the first months of 1896 (to the moment of time, when this treatise is written). 1)

So we find in the district of Skagen a Croup-free period of at least 32 years, a Croup-period of 26 years, then a Croup-free period of 16 years, again a Croup-period of 8 years, whereupon a new Croup-free period seems to begin. Nosographic researches undertaken at different times for the history of Croup in this Danish locality, where catarrhal diseases every year are frequent, must give quite opposite results: 1844 the medical officer would state Croup to be unknown at Skagen, 1870 a medical man possessing an experience of many years, would speak of an endemic appearance of Croup.

From the isle of Moen a physician having practised there since 1791, in 1838 relates that Croup, having been very rare in that isle and unknown to the inhabitants, commenced appearing in 1838. In the period 1839-59 Croup is found, now sporadicaly, now epidemically appearing; 1859-73 the disease again was seen most unfrequently. When the disease in 1846-47 commenced declining in frequency the medical officer under whom the isle ranged, ignorant of the history of the disease before 1838 pronounces his surprise at this decreasing in a place otherwise being ,,the domicile of Croup" and accustomed to its endemic appearance 2).

These examples may be sufficient for Denmark; in the treatise by the author, quoted above, numerous facts of similar kind are to be found; as far as the historical accounts can reach it is substantiated, that all places in Denmark have presented periods, when Croup has been frequent,and periods, when Croup entirely or allmost disappeared. Further it is worth remarking that the periodical appearance of Croup is most distinct in the most isolated regions and that the Croup-free periods are decreasing in length as we get nearer to the present time with its quick development of communication. The explanation of those facts is easily found.

Regarding Germany the litterature until 1850 has many statements proving Croup's having appeared in places, where the disease formerly had been unknown or rarely met with.

In Rambach's Topography of Hamburg (1801). Croup is related not to have been noticed there; but thereafter it appeared epidemically in 1891-2, as

1) vide Medicinalberetninger for Kgr. Danmark.

2) Medicinalberetninger for Kgr. Danmark.