Is diphtheria contagious? Undoubtedly it is. The contagious element is liable to be directly communicated by the patient; it also clings to solid and semi-solid bodies, and in this way is transmitted even after a long time. There is hardly any disease which can cling so tenaciously to dwellings and furniture; it can be transported by the air, though probably not to a great distance, and hence in houses artificially heated, while the windows and doors are mostly closed, rises from the lower to the upper stories; and it is for this reason advisable to keep the sick on the top floor. It is certainly transmitted by spoons, glasses, handkerchiefs, and towels used by the patient. The contagious character increases directly in proportion to the neglect of proper ventilation. That it is spread by the feces is not clearly established in my mind. I can give personally no examples of its being carried by visitors or by the attending physician; this is said to have occurred, however. The character of the disease communicated, and the local manifestation, do not depend on that of the original sufferer; thus mild cases may produce severe ones, and vice versâ, and convalescents can convey the disease in its full force. Naturally, the softer character of the tissues in children renders them more susceptible to infection, and the activity of their lymphatic system more liable to severe forms of the disease.
Many tragic cases are recorded in literature of infection by direct contact from pharynx to pharynx, or from the opening in the trachea to the mouth of the surgeon; and one of the saddest cases, perhaps, is that of the much-lamented Carl Otto Weber. Myself and others have contracted diphtheria from sucking tracheotomy wounds.
In regard to the length of the incubation periods, there can be no better authenticated facts than those contained in a report of Elisha Harris to the National Board of Health, an abstract of which is found in No. 1, National Board of Health Bulletin, June 28, 1879. The report says that in the fourth school district of the township of Newark (Northern Vermont), amidst the steep hills where reside a quiet people in comfortable dwellings, the summer term of school opened on the 12th of May. Among the twenty-two little children who assembled in the school-room in the glen were two who had suffered from a mild attack of diphtheria in April, and one of them was, at the time school opened, suffering badly from what appeared to have been a relapse in the form of diphtheritic ophthalmia. Besides, it is proved that these recently sick pupils had not been well cleansed, one of them having on an unwashed garment that she had worn in all her sickness three weeks previously. At the end of the third day of school several of the children were complaining of sore throat, headache, and dizziness, and on the fourth day and evening so many were sick in the same way that the teacher and officers announced the school temporarily closed. By the end of the sixth day from school opening, sixteen of the twenty-two previously healthy children became seriously sick with symptoms of malignant diphtheria, and some were already dying. The teacher and six of the pupils were not attacked, nor have they since suffered from the disease.
A case14 is reported of a surgeon who, while attending a diphtheritic child, had some secretion thrown into his face. Twelve hours after his right eye was inflamed and painful. The affection proved diphtheritic, and recovery was completed after several weeks only. In a case seen by me, with Dr. L. Bopp, a child removed from a house infected with diphtheria was attacked after fourteen days and eight hours.
14 Würt. Med. Corresp. Bl., 1878, No. 2.
It would then appear that, in the direct communication of the disease to healthy or nearly healthy mucous membranes—as healthy as the prevailing epidemic will allow—the period of incubation is from one or two to fourteen days. In only a small number of cases the disease has an even shorter period of incubation than this, as when tonsillotomy or a similar operation is undertaken during the prevalence of an epidemic. One may rest assured that any operation on the tonsils while an epidemic of diphtheria is at its height will be followed within twenty-four hours by diphtheritic deposits on the wounded part. To what extent we are justified in considering this a bonâ-fide incubation of the disease in a previously healthy body is, of course, another question. It seems to me that these cases positively prove that the operation is only the causâ proxima of a diphtheritic affection, and that we may take it for granted that during an epidemic every individual is more or less under its influence and affected by it, so that it needs but a wound or an accidental abrasion of the surface of the mucous membrane to call the disease into action. In a similar way, fresh wounds or morbid conditions of the mouth may call forth the disease. The ruptured vesicles of a follicular stomatitis are liable to serve as resting-places for diphtheritic membranes, and thus I have seen the complication of a follicular stomatitis with oral diphtheria; and any lacerations of the vagina during labor may become diphtheritic within twenty-four hours. If now, on the one hand, incubation depends on the condition of the affected surface, it is probable, on the other hand, that the intensity of the poison at the time plays an important part in determining the period that is to elapse between infection and the invasion of the disease.
ETIOLOGY.—Diphtheria is pre-eminently a disease of early life; in this respect it is said to differ from the genuine fibrinous bronchitis, which by some is held an absolutely different disease, and stated to occur but rarely in children. But even this statement is probably incorrect. In the spring of 1879 I met with four cases of fibrinous bronchitis in children under three years of age. The number of cases of diphtheria in adult life is not very large, while in old age it is very small. Of 501 deaths in Vienna in 1868, only 1 had reached the age of sixty-two; of more than 300 cases in which I performed tracheotomy but 2 were over thirteen years old.
I do not know that sex exerts any predisposing influence over diphtheria, yet of the six hundred cases or thereabouts of laryngeal diphtheria in which I either personally performed tracheotomy or observed the progress of the disease in the practice of others, I found the majority in males, and the recoveries in inverse proportion to the number thereof, the mortality being greater among boys. As far as age is concerned, nearly all the zymotic diseases are seen most frequently in children. They exhibit a greater disposition to submit to diphtheria than adults, if we except those under ten months. Where, however, the disease has occurred previous to the seventh or eighth month, the greater number of cases has been found under three months. Tigri reports the disease in a child of fourteen days. A child of fifteen days was seen with diphtheritic laryngitis and oesophagitis by Bretonneau, one of seventeen days by Bednar, one of eight by Bouchut, one of seven days by Weikert; Parrot mentions several cases, and Sirédey15 reports eighteen cases of diphtheria in the newly-born. They occurred in the Hospital Lariboisière in the spring of 1877, and were probably infected by the nurses of a neighboring children's asylum. Membranes were found on the soft palate, tonsils, or larynx, and also on both pharynx and larynx. One case occurred where the posterior nares alone were affected. I have met with four cases of diphtheria of the pharynx and larynx in the newly-born myself. One of these became sick on the ninth day after birth, and died on the thirteenth day; the other died on the sixteenth day after birth; the third was taken when seven days old, and died on the ninth day. The predisposition to diphtheria during childhood16 seems to be explainable by several circumstances. The mucous membrane of the mouth and pharynx in the child is more succulent and softer, and frequently the seat of a congestive and inflammatory process. The nasal cavities are small and frequently affected by catarrhs, the buccal cavity often the seat of catarrh and of stomatitis, and insufficient cleanliness leads here to irritation of the mucous membrane. Any abnormal state of the mucous membrane, with the exception of an atrophic condition and cicatricial changes, affords an excellent abode for diphtheria. The tonsils are proportionally large; in fact, we rarely see the tonsils in children completely sheltered by the arches of the palate. On the other hand, the pharynx is anything but spacious, and while the protuberant condition of the tonsils affords a resting-place for the invading disease, the remaining space is so small that it becomes a source of uneasiness to the well in many instances, and very much more than that to the child during diphtheritic tumefaction. Furthermore, we must take into consideration the large number and size of the lymphatics, which can be more easily injected in the child than in the adult, according to Sappey, and the fact of greater intercommunication amongst the lymphatics and between them and the system; for S. L. Schenck has found that the network of lymphatics in the skin of the newly-born, at least, are endowed with stomata, loopholes through which the lymph-ducts can communicate with the neighborhood, and vice versâ.17 These circumstances, although they may have no influence in calling the disease into existence, yet assist in its development and in adding to the severity of the symptoms.
15 Thèse, Paris, 1877.
16 W. N. Thursfield (London Lancet, Aug. 3d, 10th, 17th, 1878) collects 10,000 cases of diphtheria in England between the years 1855 and 1877. Of these 90 per 1000 were under a year, 450 per 1000 from 1-5 years, 260 from 6-10, 90 from 11-15, 50 from 16-25, 35 from 26-45; 25 per 1000 were 45 years and over.