Boston Medical Journal [March, 23 1922]
Infectious disease was a difficult field before antibiotics. In this article from the BMJ, 8 years prior to the discovery of penicillin, we can see a novel approach to the treatment of bacterial pneumonia.
Pneumonia refers to an infection of the lungs and at the time of this article there was not much to be done about it. The article refers to a mortality rate (how many people died) at the time of “25-30%” for “Type-1 pneumonia.” As far as what Type-1 pneumonia is, I could not find an exact definition elsewhere, but later in this journal article it seems as if the author is referring to pneumococcal pneumonia–pneumonia caused by the bacteria strep pneumoniae–as being “type-1”. This is still one of the most common bacterial causes of this disease. Certainly viruses such as influenza and COVID-19 can also cause pneumonia.
In this article the physician is advocating for the use of serum which was derived from horses. Basically, horse blood was taken and separated to use the portion of it that contained antibodies. It seems as if they were able to isolate the serum that was most active against strep pneumoniae and therefore gave it to patients to help them improve. The physician author here cites his own small study that seemed to suggest the mortality rate when serum was used was as low as 10%. He was quite convinced this treatment did help and on the surface it does seem to make sense. This is a good treatment option for the time–unless you’re allergic to horse serum, which many people unknowingly may be.
Check out Episode 19 “The Strangler” of our podcast for more info about the use of serum in the treatment of diphtheria, another particularly nasty bacterial illness which is now quite well prevented in most of the world with simple vaccination.
 McGuire, L. W. (1922). Serum Treatment of Lobar Pneumonia. Boston Medical Journal, 389–390.
[Doctor with a mustache]