It is certainly true that recovery takes place when the cause of the disease has been removed. Injuries dependent on a disease often can not be completely recovered from or healed. although the etiological factors have disappeared—i.e., when the factors have been at work for a long time. We refer to the advanced cases of atrophy, impossible of a complete cure, as the damage done to the intestine by improper feed ing and other factors cannot be repaired.
The course of each disease depends on many factors. The prog nosis is better when the number of untoward influences accompanying a disease is small. Apart front the injuries which as complications in fluence the course of disease, each disease has a typical course. This is, within certain limits, the same in children and adults. Some diseases are recognized to have a fairly definite characteristic course in child hood. We see that tuberculous adenitis predominates in children, as well as general miliary tuberculosis and tuberculous meningitis. The nosis of tuberculous disease is graver during childhood than in later life.
All attempts to explain these things are mere conjectures. It is nothing more than a paraphrase to say that the lymphatic system of a child has a special susceptibility for tuberculosis.
Tuberculosis, while haying a had outlook during childhood, has an especially poor prognosis in the nursing infant. So-called inherited syphilis also has a very bad outlook. At this time of life measles. whcmping-cough, and scarlet fever are prognostically bad. At this period resistance to all diseases is much weaker than among adults. It is hard to explain on what these facts depend. Perhaps it is that the child, who, as we know, grows most in the first years of life, has as a result of this expenditure only a small amount of resistance left for the invading bacteria.
While the course of so many diseases is more severe in the early years of life, the later years of childhood are seen to offer a more favor able outcome. Pneumonia, which is so often seen at this time, has a much better prognosis than \Ali e n it occurs in adults. As we know well, an almost perfect prognosis is given in a child under 2 years. sick acute lobar pneumonia.
The strength of the heart is of the greatest importance in the prog nosis. Since valvular disease and the causes of fatty degeneration, alcohol, tobacco, and obesity, are all absent in children, it is perfectly understandable why the course of pneumonia in a child and in an adult may be so different.
While the uncomplicated course of every disease is a typical one, as a rule it is markedly influenced by complications. Factors which in crease the source of infection give a poor prognosis. Previously exist ing diseases also have a had influence on the prognosis. Tuberculosis previously existing can well be imagined to have a very had effect on any acute infection. Unhygienic surroundings, such as poverty, defi cient care, foul and dusty air, lack of light, and inadequate nourish ment are factors having an unfavorable effect upon the course of the disease. Thus we can see that not only more diseases but severer types are seen among the poorer classes, when compared with the well-to-do. This influence on the morbidity and mortality of childhood, of unhy gienic, unfavorable, surroundings due to poverty, is enormous.