Definition. An acute, infectious disease, characterized by a high febrile onset, with headache, vomiting and sore throat, followed by a generalized punctiform rash and later, desquamation.
Symptoms. Three days is the average period of incubation, but it may be from one day to six. The poison is less volatile and less rapidly dissipated than that of measles and hence may remain effective for a longer time in connection with articles which act as a medium of contagion. Prodromal symptoms lasting from twelve hours to two days (markedly different from measles) are most important and are especially abrupt, beginning with vomiting, headache or characteristic sore throat. Convulsions may be the first symptom in children. The pulse is rapid and bounding, the skin is dry and temperature varies from 102* to 105*F.; the tongue has a creamy white coating with the papillae reddened and exaggerated, causing the so-called strawberry tongue. In fact, all exposed mucous, surfaces are reddened, engorged and covered with deep red puncta. The lymphatic glands of the neck, those of the groin or in fact those of any locality, may be enlarged. The prodromal stage terminates with the appearance of the eruption, but fever persists and other symptoms do not improve at the time.
It is customary for the eruption to appear within the first twentyfour hours of the illness. It eruption spares the face, but develops about the neck and subclavicular region and rapidly spreads to the trunk and extremities, including the dorsal surfaces of the hands and feet, all being covered in the course of the second day. It might be described as a dull or dusky red, pin-head-sized, punctiform rash grouped about the hair-follicles, which later appears as a generalized diffused reddish blush. When it has covered the entire surface, it may be distinctly scarlet in color, somewhat like the appearance of a boiled lobster but the color varies in different individuals and at different periods. The punctate form often persists upon the limbs, whereas the diffused scarlet erythema is most marked upon the trunk. The eruption can be made to disappear in the early stages of the disease upon pressure and a whitish line, which persists for a short time, may be made upon the affected surface by drawing the finger nail over it. As was mentioned before, the fever and other constant symptoms remain with the eruptive state which terminates in from two to seven days. Its maximum development is from one to three days and it is during this time that albumin may be noticed in the urine together with other symptoms of acute nephritis. The eruption disappears leaving a yellowish pigmentation of the skin, in four to ten days after the climax has been reached, when the other symptoms vanish. In severe case as well as in some mild forms, minute hemorrhagic puncta and numerous miliary vesicles may be seen if careful search is made.
Desquamation occurs along with general convalescence and appears first upon the oldest lesions. In most cases it is governed by the severity of the preceding eruption but it may be out of all proportion to it. However, it is more pronounced and characteristic in scarlatina than in any of the other exanthemata. It may be superficial and furfuraceous or t may come off in lamellated layers, as in the shedding of the cast of a toe or finger or an entire hand or foot. The nails may be shed and rarely the hair may fall out. The entire process consumes from two to six weeks, or even longer.
Two other forms are described besides the common type. One is known as septic scarlatina, which will show parenchymatous inflammation of the tonsils and neighboring mucous membrane with tumefaction, submucous involvement and glandular enlargement. It may assume an ulcerative, suppurative and even gangrenous form, which is often fatal. Toxic scarlatina is the other type and is likewise severe. It has been likened to typhus, presenting convulsive symptoms with an ill-developed, dusky red, hemorrhagic or petechial eruption. It may be accompanied by albuminuria, meningitis, diarrhoea and coma and is usually followed with fatal consequences.
Complications and sequelae are numerous and only the more important will be mentioned. The eruption may show considerable elevation, small papules, vesicles, blebs, or purpuric lesions may be present, and rarely bullous, pustular and urticarial lesions have appeared. Nephritis of otitis, with meningitis of phlebitis, pneumonia, pericarditis, pleurisy, peritonitis, persistent catarrh, keratitis, chronic adenopathy and consequent malnutrition in any of its many forms, may be expected and may make of the patient a confirmed chronic invalid.
Etiology and Pathology. This disease usually occurs but once in a lifetime and is more prevalent during the late winter and early spring months. The contagious element, which is no doubt a microorganism undiscovered as yet, is most active during the eruptive and desquamative periods of the disease. Both sexes and all ages, more particularly children and infants, are attacked. While the susceptibility to scarlet fever is by no means as universal as that shown in smallpox and measles, nevertheless the disease is often epidemic. The contagion may be conveyed from a patient suffering from the disease, by a third party, or through infected objects. As has been mentioned, the causal pathological agent has not been discovered but it may possibly be a protozoon. Like measles, there is a hyperemia due to dilatation of blood and lymph vessels with a moderated degree of exudation. The latter when it occurs is limited to the rete and the papillary layer of the corium.
Diagnosis. The typical sore throat, intense fever, punctiform scarlet rash, extending to the border of the inferior maxilla, and the yellowish-white line caused by the finger nail when passed over the surface, should distinguish scarlet fever, Erysipelas is distinguished by a peculiar distinguish scarlet fever. Erysipelas is distinguished by a peculiar, shining, smooth, glazed surface, with a sharp line of demarcation and limited spread. The febrile symptoms and the resulting desquamation should enable one to recognize scarlet fever from drug eruptions of a scarlatiniform appearance. For the differentiation of erythema scarlatiniform, see that subject. For the diagnostic features of the other exanthemata, see the table on page 216.
Prognosis and Treatment. Prognosis should be guarded, although the mortality is seldom higher than from 4 to 10 per cent. The character of the individual case, the age and general condition of the patient, and the presence or absence of complications, may modify the prognosis.
Everything should be done to prevent the transmission of the disease and to this end complete isolation of patients and their attendants, sterilization of all their articles, and thorough disinfection of the sickroom after its use are essential. Fresh air should be abundant and food and drink should be appropriate for a fever case. Tepid or cool baths may be used to reduce the bodily temperature and following this some oily or fatty substance will prove grateful and beneficial to the patient. If itching or burning is pronounced, 1 per cent. menthol, or 2 per cent. carbolic acid, in some bland ointment may be used. In general the treatment may be summed up as antiseptic and expectant. The internal medication is most important, probably more so in this disease, because of the chance of complications and sequelae, than in any of the exanthemata. See indications for Aconite, Ail., Apis, Arsenicum, Asimina, Belladonna, Bryonia, Cantharis, Caps., Carbo., acid, Crot., Gelsemium, Lachesis, Murex acid, Phytolacca, Rhus tox., Stramonium, and Sulphur.