Definition. An acute, epidemic, markedly contagious disease, accompanied by fever, catarrhal inflammation of the upper respiratory tract and a red, non- elevated or slightly elevated macular eruption.
Symptoms. After an incubative period of from ten to twelve days, prodromata appear, consisting of fever (101* to 103* F.), chills, an incessant, hacking cough, and catarrhal inflammation of the nose, larynx and conjunctiva. Rarely, there are convulsions. Prodromal eruptions have been noticed and may be urticarial, erythematous or scarlatiniform. Koplik’s spots, which appear on the mucous membrane of the palate, uvula, lips and cheeks and may be described as small, irregular, bright red spots, in the center of which is a bluish white puncture, occur in nearly ninety per cent. of all cases, and may be seen as early as three days before the actual eruption of the disease.
The eruption may be expected on the fourth day, first appearing on the forehead and temples, thence extending in one to two days down over the neck, the upper part of the trunk, and the upper extremities. By the third day it may involve the legs but these are the last and least intensely attacked. On the fourth to sixth day, the climax as regards color and maximum development is seen over the entire body, including the palms and soles. After this attainment the eruption gradually fades, the catarrhal symptoms, including the cough, becoming less annoying and desquamation ensues. The eruption may be characterized as diffuse, reddish, yellowish red or even dark or dusky red macules, varying in size from a pea to a small finger-nail, round, oval or irregular in shape but well defined and invariably symmetrical. They may be slightly elevated or not al all. Occasionally, pin-head-sized, discrete papules and very rarely, vesicles, may be noted. Whatever the lesions, they will pale under pressure, showing a yellowish tint and often becoming aggregated, particularly over the upper portion of the body. assuming a crescentic outline. Sometimes the itching and burning are insignificant as compared with the active coryza and fever.
Desquamation begins as the rash fades and appears first upon the lesions which were earliest developed. It is accompanied by cessation of fever and the production of dedicated yellowish-brown pigmentation. The scaling is usually slight and of a fine furfuraceous character. It is often so fine as to be hardly noticeable.
Complications and sequelae are many and depend upon the health of the individual attacked, and upon various hygienic conditions as well as the nature of the particular epidemic. The eruption may disappear suddenly and as rapidly reappear, may be entirely wanting, may be unusually prolonged or may be complicated by herpetic, urticarial, bullous or petechial lesions. The chief complications are referable to the respiratory tract, such as bronchitis, bronchial pneumonia and even pulmonary tuberculosis. Sequelae may include typhoid conditions, chronic pulmonary tuberculosis. Sequelae may include typhoid conditions, chronic affections of the eyes, or other exanthemata and occasionally gangrene, impetigo, furuncles and abscesses.
Etiology and Pathology. Susceptibility is practically universal, although chiefly limited to childhood, because probably the largest number of individuals are unprotected by previous attacks at that period. One attack usually confers immunity but it may occur more than once in the same individual. It is often epidemic and appears to favor the winter and spring months. Measles is contagious and infectious from the beginning of prodromata to the complete disappearance of the desquamation. The usual means of contagion is by direct exposure. Measles is the most contagious of the various exanthemata, but inoculability is still in dispute. Although specific causative agencies have been proclaimed, further research is essential before a microbic parasite can be offered as proof of the parasitic origin of measles. Much has been said concerning the micrococci and other organisms found in the blood, in the trachea, in the breath, and by postmortem but the general pathology simply represents an acute hyperemia, occasionally becoming exudative. limited to the papillary layer of the corium and the vascular perifollicular plexuses.
Diagnosis. The main points to recollect in making a diagnosis of measles are its epidemic prevalence, presence of Koplik’s spots and other prodromata, catarrhal symptoms, continuance of fever after the eruption, color of the eruption, and the possible discovery of its nature from the source of contagion. The irregular temperature record of measles, as well as the character of the eruption, should differentiate it from the erythemas accompanied by fever as well as drug eruptions and syphilitic lesions. The schema on the opposite page will serve to present the points in differentiation between the exanthemata.
Prognosis and Treatment. The outcome is generally favourable although complications, or its presence in the very young or in the debilitated, will influence the prognosis.
Treatment embraces the strictest isolation, disinfection, ventilation and such hygienic measures as are needed for fever cases. It may be necessary to treat the complications rather than the disease, but confinement to bed and measures to prevent any undue exposure are important. Locally, the surface may be sponged once daily with a weak, alkaline solution which should be cool but not cold, warm but not hot, to be followed by the application of a bland oily or fatty substance which will relieve any subjective sensation. The sick chamber should be darkened for the sake of the eyes but should be well ventilated. Internal medication is indicated in all cases, especially to modify any tendencies to complications or sequelae. See Aconite, Ail., Arsenicum, Arsenicum, iod., Bryonia, Euphras., Gelsemium, Kali bichromicum, Pulsatilla, Rhus tox., Spongia, Sticta and Sulphur.