156
The influence of Haffkine's prophylactic in favourably influencing the course
of plague, and making it run a milder course, is no doubt undoubted in those cases
where inoculations had been done some time previous to infection. The immunity
conferred is very high during the first month after inoculation, and it gradually
decreases week by week and month by month until a period is reached when the
influence is practically nil. This is well illustrated by the course of plague cases
coming in at varying periods after inoculation. In all those cases admitted within
a month or two of inoculation, it is observed that ths disease runs a much milder
course, and mortality is also low. And as the interval between inoculation and
infection becomes longer, the change for the better grows less and less, and is not so
apparent and the mortality also goes higher. Such, however, does not seem to be the
case, where inoculations had been performed within a week or so of the patients
developing plague, in fact during the period of incubation. The disease in such
cases is very unfavourably influenced ; it assumes a graver if not a more fatal form
and its normal course is unduly prolonged. This too has been well observed in some
cases treated during the last epidemic. Clinical experience has in this case been
corroborated by experiments also. Calmette in his recently published researches on
plague in connection with the Oporto epidemic, refers to this unfavourable
influence of prophylactic inoculations in animals already infected with plague germs
and in process of incubation. He infected a certain number of mice with a culture
whose virulence had been previously ascertained and which was known to kill only a
small proportion of the animals. At the same time he inoculated all of them prophy-
lactically with a small amount of a culture sterilized by 70° centigrade. The result
was that instead of most of the animals recovering, they all died, showing how
unfavourably the prophylactic had influenced them. In fact over and above the
infection, they had received a fresh dose of toxines, which brought about the above
results. This and similar other experiments have led Calmette to recommend the
simultaneous injection of a curative serum and the prophylactic in those cases where
it is apprehended that plague is incubating, and yet an immediate immunity is requir-
ed. The curative serum would confer an immediate immunity and would neutralise
any mischief already done, and the prophylactic inoculation would in the meantime
produce those changes in the system which eventually confer immunity. By the
time the effects of the former have disappeared, say from 10 to 15 days, the latter
would assert its influence. It would be worth while making a few observations on
these lines in the nest epidemic.
1 would however suggest that in such cases it would be preferable to inject
the curative serum only to give immediate immunity as it is likely that a combina-
tion of the curative and prophylactic injections simultaneously would tend to neutra-
lise the effecis of each, and then the prophylactic about 10 to 15 days after. As the
former creates no systematic disturbance, it would go a great way to allay the fear and
excitement so inseparable from plague in the better classes of people, once a case has
occurred in their family.
Sickness and mortality amongst the staff of the hospital:—
One ward-boy and one cook who wero living on the premises contracted plague ;
they were admitted into the hospital and treated with Lustig's serum, and both
recovered.
One ayah was infected with relapsing fever on two different occasions, and slio
recovered on both. She contracted the disease whilst in the discharge of her duties
in the relapsing fever wards.
Ten sweepers also contracted relapsing fever whilst working in the relapsing
fever wards : seven of them recovered, and three died.