VARICELLA.
Synonym.—Chicken-pox.
Definition.—A mild, contagious, erup tive fever, occurring chiefly during child hood and youth. The name varicella was applied to this disease early in med ical history, before it had been fully dif ferentiated from variola.
Symptoms.—After a period of incuba tion, varying, in different cases, from ten to seventeen days, the child generally feels slight chilliness. This is followed by two or three degrees of increased tem perature, slight pains in the head and back, and general lassitude. In twenty four or thirty-six hours a strictly vesicu lar eruption appears more upon the trunk of the body, but some on the face and neck. The feverish symptoms continue, and new vesicles appear, especially on the face and scalp, for three days, when new vesicles cease to appear and the gen oral feelings of indisposition quickly dis appear. The vesicles have no hard or indurated base, are mostly ovoid in shape, and filled with a slightly-turbid serum.
They never become confluent, and are at no time surrounded by a red areola of inflammation and tumefaction. Each vesicle begins to shrivel or dry up in twenty-four or thirty-six hours after it appears, and forms a thin, light-brown scab. Consequently the first vesicles are often seen dry when the later ones are just appearing. In five or six days the eruption has all become dry and the scabs fall off, generally leaving no indentations or permanent scars. In a small percent age of the cases, however, a very few distinctly pitted and permanent scars have been left, these probably resulting from scratching or otherwise causing inflammation to extend deeper into the cutis vera. The duration of the disease from the first indications of fever to com plete convalescence is generally from seven to ten days. Very rarely the ves icles appear in the mouth and fauces, and cause much annoyance to the child in eating. In a large proportion of cases the appearance of vesicles on the skin is preceded a few hours by small, red spots. A very few cases have been reported in which the eruption has presented an hemorrhagic condition. Cases have also been recorded in tuberculosis, anaemic, and otherwise unhealthy children, and leaving gangrenous, phagechenic, or troublesome sores. But varicella occur ring in previously healthy children rarely is followed by any troublesome seqneke.
Diagnosis. — The chief interest con nected with cases of varicella is in its diagnosis or correct differentiation from the exanthematous fevers: rnbeola and scarlatina, on one side, and from variola on the other. From rubeola it is at once
distinguished by the absence of cough and catarrhal symptoms and the appear ance of eruption on the second instead of the fourth day. From scarlatina it is distinguished by the mildness of the febrile symptoms and the absence of in tense redness and soreness in the fauces; and from both it and rubeola by the eruption appearing in plain, scattered vesicles containing fluid instead of mere red points or exanthems. From variola it is differentiated by the absence of three full days of active fever and severe pain in the back and head before the eruption appears. The latter presents at once an oval vesicle without any hard, elevated base as in variola; and as it progresses it begins to shrivel, then dries up in two days, and has disappeared before a vari olous papule would have completed its development into a pustule. An attack of varicella affords no immunity from variola, neither does an attack of variola, varioloid, or vaccinia afford immunity to varicella. There are, therefore, no etio logical relations between chicken-pox and small-pox.
varicella is often preceded by a scarla Uniform rash, but, while true scarlatina is always followed by desquamation. this is never the case in varicella. Leon Cerf (Presse Med., Oct. 6, 1900).
Etiology.—There are no known causes of varicella other than its own special contagium evolved in the body of the sick, and communicated to those with whom they may be in contact. It pre vails chiefly among children, and in epi demic periods, only seldom attacking persons during adult life.
Prognosis. — Uncomplicated varicella rarely, if ever, terminates fatally.
Treatment.—Rest, in clean, well-venti latM rooms, at a comfortable tempera ture, with a plain, digestible diet, and strict personal cleanliness, is all the treat ment required in a very large majority of cases of varicella. If a case is met with during the eruptive stage with scanty and high-colored urine and in active bowels, a solution of bitartrate of potassium in cold water and rendered palatable by the addition of sugar, may be given in doses suited to the age of the patient until the kidneys act more freely and the bowels are moved.
If the vesicles appear so numerous on the face as to cause much heat or dis comfort, they may be kept moist with an equal mixture of glycerin and rose-water.