Contagious 
and 
Infectious. 
Communicable 
Diseases. 
Bacillus 
Typhosus. 
In former years communicable diseases were 
spoken of as either contagious or infectious dis¬ 
eases. The term contagious was applied to those 
diseases which are transmitted by direct contact 
or inoculation; infectious to those which are 
either air or water borne. It has been developed 
by experience that many of the diseases which 
were called infectious can also be transmitted by 
contact or inoculation and also that those diseases 
termed contagious are sometimes air or water 
borne, hence the apparent necessity for the change 
to the term communicable which is used to cover 
all diseases that may be transmitted or commun¬ 
icated from a sick to a well person without refer¬ 
ence to the method of transmission or commun¬ 
ication. 
Among the communicable diseases commonly 
met with by the nurse we will first mention 
Typhoid Fever. The invading micro-organ¬ 
ism in this disease is the bacillus typhosus, dis¬ 
covered by Eberth and Koch and sometimes 
called Eberth’s bacillus in honor of one of its dis¬ 
coverers. The seat of invasion in typhoid fever 
is the small intestine in the lower part of what is 
known as the ilium, situated near the ileo-caecal 
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