TYPHOID FEVER. 379

siderable and massive development of the bacilli may
take place.

Typhoid fever is a disease which is communicable to
animals with difficulty. They are not affected by bacilli
in fecal matter or in pure culture mixed with the food,
and are not diseased by the injection into them of blood
from typhoid patients. Gaffky failed completely to pro-
duce any symptoms suggestive of typhoid fever in rab-
bits, guinea-pigs, white rats, mice, pigeons, chickens,
and calves, and found that Java apes could feed daily
upon food polluted with typhoid germs for a considerable
time, yet without symptoms. The introduction of pure
cultures into the abdominal cavity of most animals is
without effect. Frankel and Simon found that when
pure cultures were injected into mice, rabbits, and guinea-
pigs the animals died.

Germano and Maurea found that mice succumbed in
from one to three days after intraperitoneal injection of
1-2 c. cm. of a twenty-four-hour-old bouillon culture. Sub-
cutaneous injections in rabbits and dogs caused abscesses.

Losener found the introduction of 3 mgr. of an agar-
agar culture into the abdominal cavity of guinea-pigs to
be fatal.

When animals are treated in the manner described in
the chapter upon Cholera—i. e. the gastric contents ren-
dered alkaline, a large quantity of laudanum injected
into the peritoneal cavity, and the bacilli introduced
through an esophageal catheter—Klemperer, Levy, and
others found that there was produced an intestinal con-
dition which very much resembled typhoid as it occurs in
man. The virulence of the bacillus can be very greatly
increased by rapid passage from guinea-pig to guinea-pig.

In the experiments of Chantemesse and Widal the
symptoms following the injection of virulent culture into
guinea-pigs were briefly as follows: 'c Very shortly after
the inoculation there is a rise of temperature, which
continues from one to four hours, and is succeeded by a
depression of the temperature, which continues to the