SERUM TREATMENT IN TYPE I LOBAR PNEUMONIA

Pneumonia in man is not a single disease; the term includes a group of diseases, and today there is no more justification for making a diagnosis of pneumonia than there is for making a diagnosis of enteritis when the patient suffers from typhoid. This fact becomes fundamentally important when the question of serum therapy is involved. Although, as Tillett has shown, nontype specific humoral factors may be concerned in immunity to pneumococcus, yet the evidence so far available strongly indicates that the most important rôle in immunity to pneumococcus, and in recovery from infection with this organism, is played by substances in the serum which are effective only in relation to a particular type of pneumococcus. In most experimental animals recovery from pneumococcus infection, either natural or acquired, is followed by at least a temporary resistance to subsequent infection, and during recovery the blood of the animal acquires new properties.