CAUSING ACUTE INFECTIONS. 
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(endotoxins). Efforts have been made to immunize 
against the disease and to modify its course by inject¬ 
ing the killed bacteria. The results have been fairly 
successful. 
The Koch-Weeks Bacillus. 
This organism is the cause of acute infectious 
conjunctivitis, commonly called “pink eye.” It re¬ 
sembles closely the bacillus of influenza, but differs 
from it in growing on media that does not contain 
hemoglobin. 
The Ducrey Bacillus. 
This bacillus is of very small size, and has a 
tendency to form chains. It is not motile and does not 
form spores. It stains with all the ordinary dyes, but 
more deeply at the ends. It will grow only on media 
containing human blood. 
Infection with this organism is the cause of 
chancroid, or soft chancre, an acute, inflammatory, 
ulcerating sore which occurs generally on the genitals 
and surrounding skin. It begins as a small pustule 
which ruptures and becomes an ulcer, having a tend¬ 
ency to spread. The bacilli frequently extend along 
the lymphatic vessels and involve the adjacent glands 
of the groin, which may undergo suppuration. The 
bacilli can be found in the pus and discharges from 
the ulcers. Infection results generally from sexual 
contact, rarely from infected dressings, towels, and 
instruments. 
