INFECTION 3 
Bacteriemia. If the invading bacteria multiply in the blood and 
become widely distributed in the circulation and tissues, the condi- 
tion is known as septicemia or bacteriemia. 
Toxemia. If the infecting bacteria remain at the point of entrance 
and multiply there, elaborating a toxin which is absorbed and which 
causes the symptoms and possibly death, the condition is a toxemia. 
Sapremia. If there is a febrile condition, resulting from the 
absorption of the products or ptomains produced by putrefactive 
bacteria, the condition is called sapremia or septic intoxication. 
A Specific, Infectious Disease. If the invading organism is one 
possessed of definite pathogenic properties, such as the bacterium 
of anthrax, giving rise to a definite series of symptoms and lesions, 
the affection is designated a specific, infectious disease. 
Through the agency of metastasis, invading. microdrganisms 
may be carried from the point of introduction to other parts of 
the body, where they may become localized, multiply, and give rise 
to any one of many forms of lesions. It may happen that the point 
of entrance is so obscure that the resulting morbid changes are 
not easily traced to an external infection. There are many illustra- 
tions of this in comparative pathology, such for example as suppura- 
tive cellulitis. For convenience in discussion, infections may be 
divided into two clinical groups, namely: wound infections and 
specific infectious diseases, although in certain instances they cannot 
be entirely separated. 
In arriving at a clear understanding of the nature of infections, 
it is well not to be too closely circumscribed by classifications. It 
is better to look upon infections as a series of processes going on 
in the animal world due to the activities of infecting or parasitic 
microorganisms. In other words; the lesions following an infection 
are the result of a microbian parasitism. 
In the study of the various forms of infection in the lower animals, 
lesions have been found to contain, apparently as their causative 
factors, bacteria which suggest at least that certain of the supposed 
saphrophytic organisms may, under certain conditions, become 
parasitic and cause more or less local or general tissue disturbance. 
Many lesions seem to be produced by bacteria which are harbored 
normally upon the skin. When these organisms are introduced 
by accident into the living tissues they multiply and acquire, if 
they did not already possess it, the power to produce tissue changes. 
