March, 1953]
J. M. LALL AND N.
C.
SEN
27
tuberculosis in normal animals. All the calves developed sensitiveness to tuberculin
after vaccination. The vaccinated animals showed trivial tuberculous lesions
in glands of the alimentary tract, while marked lesions were found in the glands
of the controls. The authors concluded that the results obtained with vole vaccine
were unexpectedly good, better than those which followed the use of B.C.G. as a
vaccine.
With a view to determine that the vole bacillus was safe for human beings,
Sahai [1942] tested the strain on monkeys, which is the only readily available species
of animals closely related to man. One monkey was given intravenously 1.0 mgm.
of a young culture and another 10.0 mgm. subcutaneously. Both the monkeys
remained well during the entire period of observation (146 days and 126 days res-
pectively), though the monkey inoculated subcutaneously developed a local lesion
at the site of inoculation which burst, but the resulting ulcer healed spontaneously
and the animal did not show any disturbance in the general health. The one inocu-
lated subcutaneously was killed after 126 days and the other after 146 days for a
thorough post-mortem examination. No lesions were met with in any of the
internal organs and cultures made therefrom remained sterile.
The monkeys were tested repeatedly with human tuberculin both intradermally
and subcutaneously. In the former case 0.1 ml. of tubarculin diluted 1:10 and 1:50
was inoculated into the skin on the flexor aspect of the forearm, while for the subcu-
taneous test 1.5 to 2.0 ml. of diluted tuberculin (1:10) was injected under the skin
in the upper arm. In no case any characteristic reaction was observed.
It is well known that cattle and guinea-pigs infected with the vole strain of
acid-fast organisms show strong and distinct allergy ,to mammalian tuberculin, so
perhaps the negative results in these monkeys may be due to the general unsatis-
factory nature of the tuberculin test in this species of animal.
Sahai [1943 and 1944] again demonstrated the almost complete innocuousness of
this organism (strain LV 285) for monkeys. He administered doses as large as
10 mgm. intravenously, subcutaneously, intraperitoneally or by combination of the
different routes to ten monkeys, but none showed any ill-effect excepting the develop-
ment of local abscesses after subcutaneous inoculation which healed spontaneously.
One monkey was given only a single dose of the culture, others received two to
four. Two of the monkeys died of dysentery before they could be tested for
immunity. The rest, along with three controls, were injected subcutaneously in the
left axilla, some two months after the administration of the last dose of vole
bacilli with 0.00001 mgm. of a bovine culture. One of these vaccinated monkeys,
again died of dysentery after being given the test dose. Of the remaining seven
monkeys, one died of severe tuberculosis 193 days after the test dose; the rest were
destroyed after 242 to 247 days and they all showed on post-mortem examination
generalized tuberculosis of a more or less severe type and in all cases live tubercle
bacilli were isolated from the lesions by guinea-pig inoculation.
The extent of the disease in the vaccinated animals as a whole differed but
slightly from that seen in the control monkeys. So perhaps vaccination with the
vole bacillus by any route or combination of routes did not produce any appreciable
resistance in monkeys.
6A