VARICELLA. Chicken-Pox

Varicella is a benign, acute, contagious disease which occurs almost exclusively in childhood. After an incubation period of 10-14 days a rash appears, usually without prodromata, though in exceptional cases there may be fever, pains in the back and legs, malaise and even vomiting. The rash appears without particular sequence on different parts of the body, most profusely as a rule on the clothed surfaces, especially the trunk. The earliest lesions are small red macules, upon each of which there arises almost immediately a minute vesicle. The latter enlarges rapidly to about the size of a split pea. Each vesicle is thin walled, at first transparent with a faint pink halo about its base. Occasionally an oblong blister may be seen, or one situated at the edge rather than in the middle of its macule. The lesions are usually disseminated and always discrete. Sometimes an area of skin subject to pressure may be thickly set, but though the vesicles are so abundant that they compress each other they do not coalesce. The rash is very rarely both abundant and generalized. The palms and soles are seldom involved. Frequently a few blisters form on the mucous membrane of the mouth, but on account of the rapidity with which the epithelium is desquamated they usually appear as grayish round erosions. The first crop of vesicles begins to dry on the third day, their contents become turbid, the vesicles collapse and change into small brown or blackish crusts, and rapidly lose their halo.

The crusts fall off in 8-14 days. Occasionally more rapid central dessication will cause a few larger vesicles to become umbilicated. But the eruption of the rash is not always ended on the first nor even on the second day. Sometimes vesicles continue to appear even after the older lesions have begun to desiccate and we find side by side lesions in various stages of evolution. Itching is not infrequent. The vesicles may be ruptured and crusts torn off by scratching, and secondary ecthymatous infections produced which sometimes result in the formation of pockmarks. Uncomplicated lesions do not cause scars. **DIAGNOSIS:** In *variola* the prodromal symptoms are severe with an initial fever of about three days' duration. The rash appears first and is more profuse upon the exposed surfaces, i.e., the hands, wrists and face, and lesions occur on the palms and soles. All the lesions erupt the first day and are therefore always in the same stage of development. The vesicles spring from papules, not from macules, and the papules are firm, embedded in the skin, and feel like shot. The vesicle walls are thick, tough and not translucent. The vesicles are globular, multilocular, umbilicated, they run a slow course and their contents always become purulent. The lesions leave scars. When the differential diagnosis cannot at first be made the patient should be isolated and watched for a couple of days. **TREATMENT:** No treatment is required. A two per cent carbolic lotion may be applied to relieve the itching.

HST. 000001. 059