8
CALCUTTA AND ITS SUBURBS.
evening and morning, and that, as the duration of the fever is short, the record is not
so perfect as it would have been, had the observations been made so as always to secure
the highest temperature that took place being noted. Besides the determination of the
points sought for in the enquiry, it has come out so strongly than with the crusts made
use of, no certainty of success could be secured, that I propose shortly to allude to
this subject as well. Of the 16 children successfully vaccinated with crusts, only 3 suc-
ceeded on a first attempt; 9 on a second, 3 on a third, and 1 on a fourth: that is twenty-
nine attempts had to be made to vaccinate before sixteen children could be protected.
The failures come out more strongly when the points of insertion made are compared
with the number of vesicles resulting; out of one hundred and twelve points of insertions
only twenty-two succeeded.
Much of this want of success is doubtless due to want of practice in working with
crusts, and to many of the vaccinations having been made by means of the usual punctures
which is the only method allowed in the department. So great was the want of success
of the vaccinators, that I dispensed with their services and I applied the solution of
the crust myself to raw surfaces produced by scratching with a lancet.
Though undoubtedly better results were secured in this way, failed points of inser-
tion were still very frequent, and the contrast to the universal success, when working with
lymph taken direct from the arm, was very striking.
Whether in working with humanised animal virus in applying Bryce's test, or with
lymph reared from crusts, the result was so uniform that I cannot recall a single instance
of a point of insertion failing either in our hands or in those of the vaccinators.
Lymph supply.
Tubes
Lymph Supply.—One of the duties connected with this department is to supply vaccine
virus to those who ask for it in other parts of India, to enable vaccination to be begun for
the season; or, in the event of the supply of lymph at any place failing or the results of
vaccination not proving satisfactory, to renew a stock of reliable vaccine from which to
begin afresh. The chief means employed consists in sending out fine tubes, containing
fluid virus the ends of which have been hermetically closed.
their defects
The results attending the use of these tubes have been superior to those met with in
supplying vaccine either fluid or solid, in any other way. The measure of success met with
is, however, greatly short of what could be desired, and falls far below what could be achieved
with improvements in detail which during past years have come to light. It has previously,
on various occasions, been pointed out that the tubes sent to this country are defective in
construction. They are of too large a calibre, and in many cases the glass of which they are
made is too thick. The one defect deprives them of their capillary nature, and prevents the
exclusion of air to a considerable degree—a fault fatal to a great extent to the lymph
being prevented from undergoing decomposition. The other defect is also a serious one in
requiring a greater amount of heat to be applied in melting the glass to seal the extremities,
and thus running the risk of destroying the efficiency of the contained virus. While again
alluding to the remediable difficulties in the way of providing an efficient lymph supply, it
must not be lost sight of that the climate, at the season of the year when there is most
demand for virus to commence vaccination, is most unfavorable for the preservation of
lymph. On the cessation of the rains agencies leading to deposition abound, which
render it a much more difficult matter to preserve the virus than it is in more temperate
latitudes. To aid in overcoming the difficulties, as the result of experiment, it was found
that a solution of salt exercised a more favorable influence than any other chemical
means that was tried. This was alluded to in greater detail in my third special report.
mode of sealing
Since then I have been to a certain extent, disappointed with the success of this means,
for though of undoubted use, it is found in practice not to be efficacious enough to allow
of our resting contented with this improvement. In searching about for modes of supple-
menting this insufficiency, a result was arrived at which promises fairly. In sealing the
tubes by means of fusing their ends in a flame, it is necessary to leave a considerable
length of tube without lymph to guard against the heat destroying the contents of the tube.
Even with every care artificially to expel as much as possible of the air from the unoccupied
portion of the tube, enough of it is left shut up with the virus to endanger its becoming
decomposed. To overcome this source of danger, the practice has been introduced of
completely filling the tubes, and as they cannot then be sealed by fusing the glass, the open
ends are dipped into a cement containing carbolic acid, and finally a layer of Indian
rubber dissolved in the bisulphurate of carbon is laid over all to prevent the evaporation
of the carbolic acid.
In this way a tolerably efficient antiseptic plug is provided, and the virus is placed in
less unfavorable conditions for retaining its activity.