388 PATHOGENIC BACTERIA.

Wright and Semple assert that dead cultures of the
typhoid bacillus may be used for the test, as bacilli killed
by a temperature of 60° C. agglutinate perfectly. They
have the advantage of being easily kept.

Rumpf,1 and Kraus and Buswell2 report a number of
cases of typhoid which were favorably influenced by the
introduction hypodermically of small quantities of steril-
ized cultures of Bacillus pyocyaneus. These experiments
are still too new to deserve extended mention.

Following the lines of experimentation suggested by
Haffkine's researches upon preventive vaccination against
cholera Asiatica, Pfeiffer and Kolle, and Wright and Sem-
ple have used the subcutaneous injection of sterilized cul-
tures as a prophylactic measure. One c.cm. of a bouillon
culture sterilized, by heat is thought to be sufficient
Wright and Semple report 18 cases in which it was used,
and by experiment showed the blood to be changed simi-
larly to that of typhoid patients and convalescents. This
change consisted in the destruction of motility and agglu-
tination of the bacilli, as seen in Widal's reaction. It is
hoped that we can gauge the duration of the immunity
thus acquired by the frequent use of Widal's test.

One of the most important and practical points for the
physician to grasp in relation to the subject of typhoid
fever is the highly virulent character of the discharges
from the bowels. In every case the greatest care should
be taken for a proper disinfection of the feces, a rigid
attention to all the details of cleanliness in the sick-
room, and the careful sterilization of all articles which
are soiled by the patient. If country practitioners were
as careful in this particular as they should be, the disease
would be much less frequent in regions remote from the
filth and squalor of large cities with their unmanageable
slums, and the distribution of the bacilli to villages and
towns, by watercourses polluted in their infancy, might
be checked.

1 Deutsche med. Wochenschrift, 1893, No. 41.

2 Wien. klin. Wochensckrift, July 12, 1894.