4 In a paper in the British Med. Jour., 1879, vol. i. p. 307.
As for the time of year, we quote the following: "Thus, according to the census statistics, most deaths occur in the spring, there being a rise up to the middle of May. From the middle of May the number lessens largely until August, when a rise occurs and continues until October, when a decline sets in and continues until December, when a rise begins and goes on increasing until the middle of May. This rise in mortality from August to October is attributed to the wear and tear of a hot summer and the intestinal troubles then so prevalent."
The mortality statistics of this disease are uncertain. It is fatal in its complications or by inducing a debilitated condition which invites degenerative processes. The severity of the symptoms is no guide for prognosis as far as uncomplicated cases are concerned, and there is no doubt but that at present we are able to greatly reduce the mortality-rate by care and medical treatment, as well as to shorten the attack. Sporadic cases are apt to be neglected until they become complicated. When the disease occurs in epidemic form, measles is often prevalent simultaneously, and in consequence children who become affected by both diseases have a greater tendency, from debility, to become the victims of those affections of the respiratory organs which are such frequent and fatal complications of both maladies.
Instead of surprise at the mortality of this affection, the marvel is that so large a percentage of recoveries take place, when we consider that we are dealing with a disease whose lesion is a catarrh of the air-passages which seldom lasts less than two months, with a tendency to involve the lungs in one way or another, and then witness the carelessness with which, among the lower classes, the child is often treated—exposed to all weathers, under-clothed, under-fed, and probably allowed to pass through the whole attack without medical treatment. Taking this into consideration, the probability is that the mortality of this disease could be reduced to a very small figure by careful management, even if the investigations of those now seeking the microbe of pertussis do not lead to any plan, in accordance with Pasteur's teachings, which will still further lessen the gravity of the disease. Until then, we can but insist upon a rigid quarantine of schools, a registration of all cases, and the seclusion of them, as we have done to-day in the case of variola and scarlatina.
MORBID ANATOMY.—Although whooping cough is a serious disease, the cause of death is generally found to be dependent upon its complications, and there is no lesion at all characteristic of it. The chief complications and sequelæ are—bronchitis, which may become capillary; lobular collapse, which, according to Alderson,5 is frequently found; emphysema, usually marginal, probably due, as suggested by Jenner, to violent expiratory exertions; rupture of air-vesicles, with subcutaneous emphysema; catarrhal pneumonia, pleurisy, phthisis, acute tuberculosis, croup, cerebral apoplexy, meningitis, etc. As any of these complications, and others which may arise from debility, may be the cause of death, independent of the action of the specific poison itself, it is usual to divide the post-mortem appearances into those that are the result of the extension of the catarrh itself and those produced by the interference with the circulation and with nutrition from mechanical violence. Of the former, the usual causes of death are pneumonia, gastritis and enteritis. Of the latter, we have thrombosis of the cerebral sinuses, hemorrhages, emphysema, and exhaustion following constant vomiting.
5 Medico-Chir. Trans., pp. 90, 91, 1830.
Tubercular disease of the lungs or of the brain is apt to be a cause of death. Convulsions carried off 5 of the 12 fatal cases reported out of 208 by Meigs and Pepper. This may be due to congestion of the brain, especially in teething children. Spasm of the glottis with sudden death is occasionally found. In such cases there is found intense congestion of the brain, also of the liver and kidneys, and at times of the mucous membrane of the stomach and intestines, as well as of that of the respiratory tract.
In all cases, especially at the teething age, sudden death may occur because effusion into the ventricles of the brain or the formation of heart-clot has taken place. It is important to know this, that active treatment applied early enough may save the patient.
PROPHYLAXIS.—Should the interesting and seemingly conclusive statements of Dolan and the microscopic investigations of Carl Bruger6 receive the endorsement of future workers, the subject of prophylaxis will assume a degree of importance which hitherto it has only maintained with the medical profession. No one has doubted that the disease was contagious, and yet there is no affection which has attached to it a corresponding fatality that is so carelessly dealt with as pertussis.
6 Bruger of Bonn, in the Berliner klinische Wochen., describes at length the special micro-organisms of pertussis. They appear as small elongated elliptical bodies of unequal length, the smallest being double as long as broad. High powers show subdivisions in the largest specimens. They are generally isolated, but may appear in groups. They bear some resemblance to Leptothrix buccalis, the spores of which are often found in whooping-cough sputa. Occasionally the bacillus is seen inside the mucous corpuscle in the sputum. They stain in the usual way, fuschin and methyl violet. This bacillus is not found in any other kind of sputum, is very abundant in pertussis, and increases in direct proportion to the severity of the disease.