610 ACUTE INFECTIOUS DISEASES. 



skin, not only induce inflammation at the point of application, but alsc 

 increase the predisposition to other cutaneous affections. Many chil- 

 dren, who have never previously suffered from any exanthema, are 

 affected for months with moist eczema of the face, after having their 

 ears pierced, as well as after vaccination. But it is only in rare cases 

 that the occurrence of scrofulous affections is due solely to vaccination, 

 and is not influenced by other causes, such as weaning and teething, 

 which usually take place about the time that vaccination is done, and 

 it is still rarer for life to be endangered by the operation. Complete 

 ignorance of statistics of mortality, which show a decided decrease of 

 mortality since the introduction of vaccination, must be the only ex- 

 cuse for urging these exceptional cases as grounds against vaccination. 

 It may be readily seen why more children die of measles, scarlatina, 

 croup, and hydrocephalus, since small-pox leaves a larger number for 

 these diseases to attack, as it were. But the slight increase of mor- 

 tality in the above diseases does not, by any means, equal the diminu- 

 tion of mortality in variola. Unless the occurrence of a small-pox 

 epidemic throws all other considerations into the shade, I do not vac- 

 cinate weakly children, inclined to scrofula, during their first year, but 

 wait till the second or third, after the teeth have developed, because I 

 am satisfied that, in such children, very much depends on protecting 

 their first development from injurious influences. 



ANATOMICAL APPEAEANCES. The anatomical changes in the skin 

 after the first vaccination exactly resemble those in variola, except 

 that they are confined to one point. The third day after the vaccina- 

 tion there is a small red nodule at the point of operation ; the fifth or 

 sixth day this changes to a vesicle ; by the eighth day the vesicle at- 

 tains the size of a lentil, and has a central depression, the umbilica- 

 tion, and a cellular formation. The ninth day the contents of the 

 pock become cloudy and whey-like, while a broad, dark-red halo de- 

 velops around then- periphery ; on the tenth day they become puru- 

 lent; from this time the pock begins to dry up, rarely rupturing. 

 Toward the end of the third week, or even later, the crust falls off. 

 and leaves a somewhat excavated, round, white cicatrix, whose base is 

 stippled and ridgy. The umbilication of the vesicle, according to 

 Simon, depends on the puncture made during the vaccination ; as a 

 result of the inflammation caused by the puncture, there is an adhesion 

 of the epidermis to the cutis, hence, when a serous liquid is subse- 

 quently effused between the two membranes, the epidermis does not 

 become loosened at the point where it is most firmly attached ; this 

 hypothesis is supported, among other points, by the fact that the form 

 of the umbilication corresponds to that of the wound : if we have 

 vaccinated through a puncture, the depression is small and round ; if 



