THE NATURALIST AND COLLECTOR 
6l 
Antitoxin and Other Serum Cures. 
O CLAIMS of originality are made 
for this article. It is simply an 
effort to put into clear, untech- 
nical language an explanation of wliat 
Tuberculin, Antitoxin, and other “se¬ 
rum cures” are; and to give the gen¬ 
eral reader some idea concerning them. 
Many of the infectious and contag¬ 
ious diseases of man and the lower 
animals have been proven to be caused 
by bacteria and almost all are sup¬ 
posed to be so caused; (we must of 
course exclude jthose diseases caused by 
animal parasites). 
The bacteria are a very low class of 
microscropic plants and of very simple 
structure; some rod shaped, others 
bead like, either singly or in chains, 
while still others are like small spiral 
coils. They increase in number by 
simply dividing- into two parts, repeat¬ 
ing the process within a |short time. 
The different genera—i. e., Bacillus’ 
Diplococus, Spirillum, Bacterium, etc. 
—are named from their morphological 
peculiarities. Every species of bacteria 
has certain peculiar ways of growing 
when “planted” or inoculated upon 
beef broth, gelatin, blood serum, etc., 
and also certain reactions toward ani- 
lin dyes. It is by “culture” experi¬ 
ments and by staining that the differ¬ 
ent species are distinguished. Each 
species also produces during its growth 
one or more chemical substances 
known as plomaines, toxins, etc. The 
product varies with the species. Now, 
if for illustration, a single Tubercullis 
bacillus' (Koch’s bacillus), was placed 
in a culture tube of blood serum it 
would rapidly grow and divide until 
there w r ould be millions of bacilli in 
the serum. During their growth these 
bacilli would produce a substance 
known as the poison or toxin of tuber¬ 
culosis. This toxin in small quantities 
would stimulate the increase of bacilli 
but as the quantity of toxin increases 
it would check the growth of the 
bacilli and finally kill them. In the 
human body the bacilus tuberculosis 
produces consumption, also tuber¬ 
culosis of the bowels. Koch supposed 
that by injecting serum in which the 
bacilli had grown, i. e., serum contain¬ 
ing the toxin of tuberculosis, he could 
cure the disease. This serum he 
called Tuberculin, also known as 
Koch’s lymph. The bacilli are killed 
by heat before the Tuberculin is used 
so that it is simply a solution of the 
toxin of tuberculosis. It was found 
that Tuberculin would not cure the 
disease but in all persons or animals 
infected by the disease it caused a 
rapid rise of temperature for a short 
time and hastened the course of the 
disease. It is now used only to detect 
tuberculosis in cattle and other domes¬ 
tic animals. 
Now as to Antitoxin and other serum 
cures. These are based upon the theory 
of immunity. Behring and Ehrlich 
found that by injecting small quanti¬ 
ties of virulent poison under the skin of 
an animal, allowing the animal to re¬ 
cover and • repeating the process they 
could arrive at a point where the poison 
would have no effect and this tolerance 
is called “conferred” or “artificial im¬ 
munity” as it is not naturally inherent 
in the animal but produced artificially. 
It was also found that this immun¬ 
ity could be conferred upon other ani¬ 
mals by injecting certain quantities of 
serum from the blood of “immunized” 
animals, and that this transferred im¬ 
munity would last for some time and 
protect the animal from disease caused 
by the initial poison. 
