Mar. 1,1925 
Vaccination Against Babies in Dogs 
437 
months. None of the remaining vac¬ 
cinated dogs nor any of the control dogs 
developed the disease. The small 
pieces of brain material composing this 
virus and the length of time in glycerin 
evidently led to its deterioration. It 
is significant to note, however, that the 
only animal to succumb in this lot was 
a vaccinated one. This experiment 
appears to indicate that a certain 
amount of immunity can be produced 
by a single injection of vaccine against 
one strain of virus, but practically none 
against another strain. 
EXPERIMENT NO. 4 
The fourth experiment was a repeti¬ 
tion of the previous experiments, except 
that a still different street virus was 
used for exposure. 
The source of the street virus was 
Washington, D. C.; dog to rabbit, to 
dog 630. A 1:10 dilution of the hippo¬ 
campus and medulla of dog 630 was 
used for exposure virus. 
The results are given in Table IV. 
Table IV may be summarized as 
follows: Ten dogs were given a single 
injection of vaccine, and later, together 
with 6 control dogs, were given an 
intraocular injection of street virus 
from dog 630. Of the 10 vaccinated 
dogs 3, or 30 per cent, died of rabies, 
while of the 6 control dogs all suc¬ 
cumbed to the disease. 
In this experiment distinct protection 
was afforded by a single injection of 
vaccine. All the control animals suc¬ 
cumbed to the disease with a short in¬ 
cubation period, which probably indi¬ 
cates a high degree of virulence for 
the exposure virus and a severe test 
on the efficiency of the method of 
vaccination. 
EXPERIMENT NO. 5 
The fifth experiment had for its 
object the exposure of vaccinated and 
nonvaccinated dogs to the bites of a 
rabid animal. 
Dogs 56, 57, 58, and 59 were vacci¬ 
nated animals, and dogs 63, 64, and 
65 were controls used in experiment 
No. 3, lot No. 3, which had failed to 
develop rabies after intraocular ex¬ 
posure. Dogs 82 and 83 were normal 
dogs used as controls. 
The dog to which the above- 
mentioned animals were exposed was 
the one which after death furnished 
the virus for exposure in experiment 
No. 4. The source of the virus was 
Table IV .—Data of experiment No . 4 
Dog 
No. 
Vac¬ 
cine ° 
Amount 
injected 
Date vaccine 
was injected 
Date exposed 
to virus b 
Result« 
Date of rabbit 
inoculation 
Result 
66 
A_ 
C.c. 
5 
June 14,1923 
_do_ 
Nov. 20,1923 
_do. 
Alive, April 20, 
1924. 
.do.. 
67 
B_ 
5 
68 
A. 
5 
_do_ 
.do. 
.do.. 
69 
C... . 
5 
Aug. 4,1923 
_ _ do_ 
__ _ do_ 
_do.... 
70 
C- 
5 
.do_ 
.do.. 
71 
D_ 
5 
_do. 
.do. 
_do_ 
72 
B_ 
5 
Sept. 5,1923 
_do. 
.do. 
Dead, Jan. 17, 
Feb. 4,1924 
Dec. 27,1923 
Dec. 11,1923 
Dead, Feb. 19, 
73 
B_ 
5 
_do_ 
1924; rabies. 
Dead, Dec. 26, 
1924; rabies. 
Dead, Jan. 11, 
74 
D_ 
5 
.do. 
_do. 
1923; rabies. 
Dead, Dec. 10, 
1924; rabies. 
Dead, Dec. 27, 
75 
D_ 
5 
_do. 
_do. 
1923; rabies. 
Alive, Apr. 20, 
1924. 
Dead, Dec. 11, 
1923; rabies. 
Dead, Dec. 8, 
1923; rabies. 
Dead, Dec. 12, 
1923; rabies. 
Dead, Dec. 11, 
1923; rabies. 
76 
Control 
.do.. 
77 
dog. 
...do.... 
1 
.do. 
78 
.. do_ 
.do. 
79 
.. do....! 
! 
i 
_ __ do_ 
80 
...do.... 
j 
.do.! 
1923; rabies. 
Dead, Dec. 10, 
1923; rabies. 
Dead, Dec. 7, 
81 
do __ 
_do.. 
I 
, 
rabies. 
° Vaccines A, B, C, and D were from four different commercial houses manufacturing this product. 
h The virus consisted of a 1:10 dilution of the medulla and hippocampus of dog 630 dead of rabies; 0.1 
c. c. of this material was injected into the anterior chamber of the left eye. 
« Diagnosis of rabies was made by microscopic examination, and in vaccinated dogs was also confirmed 
by rabbit inoculations. 
