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For more particulars on this subject, I refer to the adjoined report of Veterinary-
Surgeon Ranina.*
When a horse has recovered from the effects of one injection, a second one is
made, and so on, until immunisation is obtained.
The quantity to be injected, and the intervals between the single injections,
have been subjected to some variations in order to find out the best and shortest
way of immunisation. Valuable data have thus been obtained, which require,
however, further confirmation.
Generally, it can be said that the efficacy of the serum is, within certain- limits,
in direct proportion to the quantity of the immunising material injected.
The time required for efficient immunisation before the first bleeding, is, on the
average, 3 to 4 months.
The horses are bled from the jugular vein. Blood to the amount of 5 to 7 litres
is withdrawn and kept in ice till coagulation has taken place. The separated serum
is then decanted into sterile bottles, fitted with rubber corks, and kept in a dark
and cool place.
In Bombay, the serum was usually prepared just before it was needed, in order
to prevent possible deterioration. The serum sent out from Florence ( for the trans-
port of which special arrangements had been made with the P. & 0. Co.) arrived
sometimes in an altered condition and could not all be used.
It is needless to say that all manipulations involved in the preparation have to
be conducted with extreme precautions in order to avoid accidental contamination.
When the horses have recovered from one bleeding, the immunisation begins-
•again and is achieved in shorter time. So a horse may be bled and immunised three
to four times, giving altogether about ten litres of serum, which is approximately
sufficient for the treatment of 100 patients.' I say approximately, as, on the one hand,
the same amount of blood gives sometimes less serum, owing to incomplete coagulation:
whereas, on the other hand, a serum- with inferior c-urative properties has to be
iisod in larger doses.
After the fourth bleeding, the horses are, as far- as experience goes, so reduced
in their vitality, that they are considered unfit for further immunisation. It may
even be that a horse becomes unfit much earlier, as it happened with horse No. 6
immunised at Parel, which, after the first bleeding, never recovered again.
Before using the serum in human beings, it was always tried on animals to
ascertain its curative properties. The single dose used for treatment in patients was
cn an average 20 c.c. (5£ drachms), the largest single dose was 40 c.c., the largest
collective dose 200 c.c.
The injections were made usually nnder the skin of the arm or thigh after care-
ful disinfection. In a few moribund patients, injections directly into a vein were
tried, but without effect. In others, the serum was injected into the bubo itself :
this practice was abandoned, as it was very painful and without better results.
The injection of the serum does not cause special pain and no local reaction
v/luitever. The serum is absorbed in a few minutes. Abscesses never occur, if the
disinfection of the skin and syringe is carefully done ; in some cases, an urticarial
rash appeared after injection.
* Tbii report only accompanies the Commissioner's copy.