STANDARDISATION OF CALMETTE'S ANTI-VENOMOUS SERUM
WITH PURE COBRA VENOM :

The Deterioration of this Serum through keeping in India.

THE standardisation of an anti-venomous serum is of great practical as
well as theoretical importance.

     It is the practical side of the question to which we propose to confine our-
selves in this paper.

     The snake venom which M. Calmette ¹ employs, both for the purpose of the
immunisation of his horses and for the purpose of the standardisation of the
serum recovered from those immune horses, is a mixture of colubrine and viperine
poisons, the former making up about 80 per cent. of the mixture. A solution of
this mixture is heated at about 73° C. for half an hour and then filtered. It is this
mixed and heated poison which is employed at Lille for both the purposes above
mentioned.

     Myers ² has correctly pointed out that as we have in all cases clinically to
deal with intoxication by a pure venom, either colubrine or viperine, and also by
an unheated venom, it is preferable, if the true value of this serum as a curative
agent against snake-bite is to be determined, to use a pure unheated poison for
its standardisation. The object then of our investigation was to ascertain, as
exactly as possible, the neutralising power of Calmette's anti-venomous serum
when tested with pure, fresh and carefully dried cobra poison. Further, in con-
sequence of the observations made by us in a recent case of cobra intoxication,³*
we have extended our investigations so as to ascertain if any deterioration of the
serum takes place through keeping in this country.

     In another communication we hope to be able to record the results of similar
experiments made with the venom of Russell's Viper (Daboia Russellii).

     The method of standardisation of the anti-venomous serum which we
adopted in our experiments was the method now recognised as giving the most
accurate results. It is based on the almost generally acknowledged fact, that
snake poison toxin and its anti-toxin interact directly, and that this neutralisation
is, so far as our knowledge goes, independent of vital activity. The evolution of
this method is, briefly stated, as follows. The method which M. Calmette⁴
recommends and still practises is the following :—The dose of venom (mixed and

     * Reported to Government' on 24th and 25th January 1901, vide Plague Research Laboratory's No.
130, to the address of the Secretary to the Government of India, Home Department.