ANTITOXIN 
511 
fear of acquiring lockjaw from the vaccine. It has been 
established that proper vaccine matter never contains the 
germs of lockjaw, and if this disease then occurs, it is due 
to failure in keeping the arm clean during the period when 
the vaccination scar is forming. 
Immunity to disease is now being produced through 
inoculation. The patient is inoculated, that is, there is 
introduced into his circulatory system a virus, or serum. 
Each disease has its own virus, as the vaccine in smallpox, 
and this virus produces a mild form of the disease. This 
causes the cells to become resistant to the germs or microbes 
of the specific disease. Inoculation is being widely used for 
the prevention of typhoid fever. All soldiers are required 
to take this treatment. It would be desirable for all people 
to become immunized against this disease, but those who 
travel extensively and thus have to drink all kinds of water 
and milk should certainly undergo this treatment. 
Vaccination and immunization reduce the liability of 
death in case the disease is acquired, but they do not abso¬ 
lutely prevent the disease. If a vaccinated or immunized 
person gets an overwhelming number of germs, he may have 
an infection of a slight kind. But the liability of contagion 
is reduced to a minimum. 
391. Antitoxin. — We cannot say definitely why vaccina¬ 
tion and immunization act as they do. It is known that 
if a poison (toxin) produced during a case of diphtheria 
is gradually introduced into the blood of a horse, a sub¬ 
stance is produced which destroys the injurious effects of 
the diphtheria poison. The serum from the blood of the 
horse is called antitoxin, and may be preserved for use at 
any time to destroy the influence of the diphtheria poison. 
A given amount of this antitoxin is introduced into the 
blood of the patient suffering from diphtheria, and usually 
counteracts the poison of the disease. This treatment has 
saved countless lives. It is estimated that in the ten years 
