As a rule the child's general condition is so little disturbed that it is with difficulty that it can be kept in bed. There is usually little or no fever. The first night may be a little restless, the appetite poor and after that the child feels well again.
According to Thomas and Rille there is nearly always some tem perature even if it be trifling and of short duration, and this may last two or three days or even much longer. The author has observed a case where there was continuous fever for eleven clays. There is no regular temperature curve nor does the severity of the fever depend on the amount or duration of the eruption. The temperature does not furnish any differential point between varicella and light variola cases. In variola there is a fever-free period at the time of the appearance of the eruption, this may be wanting however in some cases. On the other hand in varicella the fever may disappear and recur later. Fever due to suppuration has been reported by Desandre (1901) Lanhartz (1897) and Combv.
The eruption causes but trifling inconvenience, but some patients, may complain a great deal on account of it, especially that there is something sticking or biting them. Itching may be present in some cases.
Severe symptoms may conic on late as well as in the prodromal stage, even death may result. Fiirbringer (1S96) has reported a case of undoubted varicella when the child died without there being any apparent complications.
The Exanthem.—There is no great difference in the formation of the variola and the varicella vesicle. A light variola may resemble varicella or varicella may exceptionally resemble variola. A single vesicle may resemble variola in an otherwise typical varicella. The varicella vesicle is not as most recent descriptions give it made up of a single chamber, but of ninny like variola. Primary umbilication is not infrequently seen but it disappears more quickly than in variola. Secondary umbilieat:on occurs from the drying of the older central part more quickly than the newer periphery.
The contents of the vesicles are not always clear throughout. but may be either watery, milky, purulent or even hemorrhagic and second ary suppuration of the vesicle is not infrequent. The lilemorrhagic and purulent forms of the disease will be considered later. More rarely the vesicle becomes filled with air, which is drawn in through the injured epidermis as the contents of the vesicles is absorbed (Windpocken, Varicella ventosa, siliquosa, emphysematica).
It is incorrect to state that there is no stage of papules and inflam matory infiltration of the skin. In the ordinary course of the disease the physician rarely sees the papules which are not very prominent and of short duration. Sometimes, however, papules one or two days
old may be noted. Microscopic sections show that the skin is always infiltrated even though the redness is scarcely apparent and it is not uncommon for a papule to attain the size of a- smallpox papule or vaccinia pustule. In severe cases there are regions of the body on which the skin between the pustules is swollen and of an erysipelatous redness.
The absence of scarring does not differentiate varicella and variola. When the disease is protracted or when there is secondary infection, bad treatment, scratching or constitutional disturbance, the healing may be delayed and there may be destruction of the skin and permanent scarring may result. It may be difficult or impossible to tell these scars from smallpox scars. The number of these scars is seldom great and a tendency to decrease in size is noted as time goes on.
The histologic picture varies. If one chooses typical varicella vesicles, those in which there is no purulent exudate and about which there is no infiltration, and compares them with the fully developed smallpox pustules, the difference between the two is most marked. If, however, one chooses the varicella-like vesicles from a light case of smallpox and compares them to a typical varicella vesicle or on the other hand compares typical variola pustules with the eruption of varicella varioliformis, one finds no difference. Unna (1S94) at least came to these conclusions as a result of his investigations and lately Heubner has expressed the same opinion. By examining the panying figure (Fig. 63) kindly lent by Professor Riehl, and paring it with a section of a variola vesicle, one sees that the processes are of the same general nature and differ only in intensity and duration. The vesicles appear usually first upon the scalp and face but often simultaneously on the entire body. New crops of vesicles appear from time to time so that one finds all stages of the eruption at the same time on the same part of the body. In smallpox the eruption appears first on the face, a day later on the trunk and two days later on the hands and feet. The eruption is about the same size and thickest upon the face and backs of the hands and wrists. In irregular cases of variola the distribution may be as general as it is in varicella and the eruption may appear in crops. In Fiirbringer's case (1S96), which was the start ing point of the last Berlin epidemic, the diagnosis of chicken-pox was made upon the appearance of the eruption in successive crops, on the other hand varicella is seen in which all of the eruption appears simultaneously.