APPENDICES.
xvii.
paste, to which I add the lanoline just before using it upon the calf. I found when I first
began to manufacture glycerine vaccine paste of a strength of 1 in 4, that the results
obtained on calves were less satisfactory than those obtained with the same vaccine paste
in children, but that this glycerine paste, when further diluted with two parts of lanoline,
produced a good result on calves, possibly because in the denser tissues of the calf the lano-
line aided the penetration of the vaccine. I do not consider my experiments in this direc-
tion conclusive, but I have always obtained better results by preparing the paste in this
manner for vaccinating calves.
From time to time I have imported lanoline vaccine paste from the Mysore Government
Vaccine Institution at Bangalore wherewith to vaccinate calves whenever I found that the
strain of vaccine in use at this depôt was deteriorating in potency. There is no doubt that
the vaccine does deteriorate after a time by passing through a succession of calves at
Taunggyi, and the strain requires to be renewed from time to time. Bangalore lanoline
vaccine has usually given good results upon calves here, but when calves in poor
condition have been vaccinated with this lanoline vaccine in the hot weather, they have given
little better results than was obtained by locally prepared vaccine paste, showing in my
opinion that the unsuitability of the calves, and not a fault in the method of preparing the
vaccine paste, was responsible for the poor results obtained with Taunggyi vaccine paste.
All instruments used in the preparations of the vaccine paste and in vaccinating and
collecting the vaccine from the calves are carefully sterilized in boiling water before use.
The lanoline and glycerine are sterilized by subjecting to the temperature of 212° Fahr. in a
water-bath and for quarter to half hour. This sterilization of these ingredients of the vaccine
paste is an innovation introduced by myself during the year under review; it was not the
custom in the time of my predecessor so far as I can ascertain. I have not found that the
glycerine paste retained its potency any longer through the glycerine having been sterilized by
heat than when it was not so sterilized. Glycerine being itself a germicide as is shown by its
destroying all extraneous bacilli in the vaccine mixed with it, within a period of four weeks,
(vide Copeman on "Vaccination: its Natural History and Pathology. Milroy Lectures,
1898)," it would seem to be unnecessary to sterilize it by heat before mixing with vaccine
pulp. Lanoline is no doubt rendered innocuous by sterilizing it, and vaccine paste prepared
with it will probably keep sweet longer than if the lanoline is not sterilized. According to
Copeman, lanoline possesses no germicidal properties, and at this depôt it has been found
to allow of the growth of moulds upon the surface of vaccine paste prepared with it even
when there was one part to four of glycerine mixed with it. A larger proportion of glycerine
than this seems to be necessary to preserve the vaccine paste from the growth of extraneous
baccilli and moulds. While operating upon the calves, and during the preparation of the
vaccine paste, the clerk wears a clean cotton apron and cotton sleeves tightened around the
wrists.
The work of grinding the vaccine glycerine in a small glass mortar is prolonged and
tedious, and occupies many hours during which the vaccine paste is liable to contamination
by germs introduced from the air, the clothes of the operator, and other sources ; the glycerine
should, in theory, destroy all such germs in time. A more complete safeguard would be gained
by the employment of a grinding and mixing machine which performs in quarter of an hour the
work which would take several hours to do by hand in a mortar. Glycerine takes over three
weeks to completely destroy extraneous germs in the vaccine paste, and as the paste pre-
pared here does not in many instances retain its potency longer than three weeks, it must be
used before the expiration of that period, and therefore before the extraneous germs are all
destroyed. Hence the necessity for rapid mixing to prevent entry of germs.
The glycerine vaccine paste is distributed to other stations and to district vaccinators
in small compressible leaden tubes containing 25 grains each. Experiment shows that ½ grain
of glycerine or lanoline vaccine paste is sufficient for four insertions, i.e., one operation. I
have myself fully vaccinated 50 children with 25 grains of glycerine vaccine from one tube
obtaining 100 per cent. of successes, and 97 per cent. of successful insertions (this paste
was prepared 20 days before the date of its use).
The leaden tubes have two disadvantages—
(1) They are difficult to fill.
(2) It is almost impossible to prevent the inclusion of some air with the vaccine
paste, and exposure to air appears to be a cause of the deterioration of
vaccine paste. Glycerine vaccine paste of a strength one in four is too
viscid to draw up into capillary tubes. I have satisfied myself of this fact
by experiment.
In Europe glycerine vaccine is supplied to the public in England, France and Germany
in capillary tubes containing sufficient vaccine for one case each.
The composition of the vaccine is as follows :—
Bovine lymph ...
Glycerine ...
Distilled water ...
1 part
7 parts
7 parts
i e., 1 in 15 parts.