OBSERVATIONS ON USE OF ANTHRAX SPORE VACCINE IN
MADRAS
By G. R. VISWANATHAN, M. RAMAKRISHNA PILLAI and S. VENKATARAMA AYYAR, Veterinary Investiga-
tion Service, Madras
(Received for publication on 29 July 1946)
T HE use of anthrax spore vaccine in Madras was introduced in 1939. The results have been
referred to in the reports of the Disease Investigation Officer of Madras [Viswanathan, 1937-45]
and in the report of the Civil Veterinary Department of Madras for the year 1933-34. This article
summarises some of the results observed.
Apart from vaccination, it is recognized that in order to achieve success in checking the disease,
other measures required are, an early and correct diagnosis, as well as the proper disposal of
carcases and proper cleaning of contaminated areas. While in most cases anthrax can be readily
diagnozed by microscopical examination of blood smears taken immediately after death, the clinical
symptoms and history are very helpful in making a tentative diagnosis. As to the use of anthrax
serum for control, serum sometimes appears to be efficient in bovines and also in sheep in fresh centres
of infection. In our hands, however, it has not proved effective in controlling outbreaks of 'subacute
anthrax' in bovines. that is, outbreaks which tend to run a prolonged course. Nor has the serum
been found helpful with sheep and goats, except in enzootic areas.
SPORE VACCINE IN PRACTICE
The vaccine used was obtained from Mukteswar during 1939 to 1941 and from 1942 to date.
During 1941-42 a thousand doses of vaccine prepared in Burma were used. The vaccine was given
in 1.0 c.c. dose subcutaneously in the neck in bovines, sheep and goats; in elephants the injection
was given into the subcutaneous tissue behind the elbow and was followed 20 days later by a second
dose of 3.0 c.c. The vaccine has good keeping quality and under favourable storage conditions
remains unchanged for some time, so that no difficulty was experienced in its transport and distribu-
tion in the field.
Unless assured as to the safety of the vaccine, small-scale preliminary tests were conducted on
the particular species to be vaccinated. Thus in 1941-42 the Burma vaccine was tried during an
outbreak of anthrax on six bovines, of which, four bullocks were given at the same time anthrax
serum in dose of 20 c.c. There were no reactions. On another occasion spore vaccine from Mukteswar
was used together with anthrax serum on five goats and 74 lambs. Serum was used for all the animals
in dose of 20-40 c.c. the goats were given 1.0 c.c. of the vaccine and the sheep 0.5 c.c. The goats died
of anthrax while the sheep were unaffected, showing that the vaccine was too severe for goats, at
least in the dose given. This is in accord with the knowledge that it is more difficult to produce a
suitable vaccine for goats than for sheep, though with the latter species also no small care has to be
taken. As a result of the experiment just referred to, a milder vaccine and one suitable for goats as
well as sheep is now supplied from Mukteswar. In company with Mr V. R. Rajagopalan, a safety
test of spore vaccine was made on an elephant belonging to the Forest Department. In this case
the vaccine was found to be safe when given in dosage of 1.0 c.c. followed 20 days later by 3.0 c.c.
In Table 1 are shown the species and number of animals treated with the spore vaccine, both at
the time of outbreaks and in localities where no outbreak was prevailing. No animals could be left
as unvaccinated controls in the particular herds or flocks being treated, though in the same villages
some herds or flocks remain unvaccinated. In the case of sheep and goats some animals in free
areas adjacent to the enzootic areas were first vaccinated as a trial. The results were encouraging
in the sense that anthrax failed to appear in areas where anthrax carcases had been carelessly disposed
of and where contamination was likely to have occurred. The elephants mostly belonged to the
Forest Department and a few to private owners.
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