MEDICAL ASPECTS OF PLAGUE.]
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place on the outbreak of the epidemic was very largely confined to women and children.
The withdrawal of the women gave rise to a marked decrease in the birth-rate of the
city, which during the ten months under review fell below the mean of the preceding
five years for the same priod by 3,685.*
That young adults should give the highest number of admission is not surprising, as
they form the largest proportion of the population, and they travel about more, and so are
brought more frequently into contact with the disease. The greatest number of admissions
into hospital occurred among domestic (cooks, hamals, massalchis) and personal servants,
(vide Table V.) who formed 20 . 88 per cent.: mill-hands came next, forming 11*52 per cent. :
coolies, 8 . 8 per cent. The comparatively large number of dhobies (native washermen),
darzis (tailors), gaolis (milkmen), and hajjáms (barbers) deserves notice, as from their
occupation they are likely to spread the disease. The large percentage of admissions among
domestic servants is doubtless due to the disease being detected early, and to their masters
seeing that they were taken to hospital.
It is impossible to estimate the influence of race and caste on susceptibility to plague,
owing to Europeans living under very different sanitary conditions from natives, and to the
effect of social position in altering the conditions obtaining among natives themselves ;
besides, correct statistics cannot be obtained as to the native population present during the
epidemic and the numbers attacked by plague.
That more males than females were attacked (vide Table IV) is probably entirely owing
to the former having been present in larger number.
The exciting cause of plague is the plague bacillus of Kitasato, which is believed to
gain admission to the body, usually through an abrasion of the skin, or more rarely of a
mucous surface. In a number of instances in the present epidemic points of inoculation
were found on the extremities of plague patients, from which plague cultures were obtained.
and in these cases buboes were found above the point of inoculation. In the majority of
mstances, however, no local indication could be found marking the point at which the
microbe was implanted.
Less frequently infection is believed to have occurred in the
respiratory organ or in the digestive tract. When the disease appears in the form of
primary plague-pneumonia, it may be caused by the inhalation of bacilli disseminated
in the air by patients as they cough, or it may be carried by the blood vessels, or lymphatic
vessels to the lungs, where it develops.
When a monkey is inoculated by pricking its hand with a needle dipped in plague
culture, the slight wound made disappears in a couple of days, and leaves no indication of
the point at which inoculation was performed. After four or five days a bubo appears in the
axilla or at the bend of the elbow, and the symptoms of plague develop. The lymph from
the bubo in these cases contains plague bacilli in great numbers, from which cultures can
be made. In the case of man also, as already mentioned, the point at which inoculation
occurred was but rarely discovered. Plague bacilli could, however, be obtained in immense
members, and cultures made from lymph taken from buboes. In septiœmic cases they
could be obtained from the blood as well as from lymph from enlarged glands ; «and in
pneumonic cases they were obtainable from the sputa and from enlarged glands when
present. Bacilli were probably also present as a rule in the sputa, vomit, urine and fæces
of plague patients, but they were hardly ever found in the blood taken from the finger in
cases where a bubo was present from the first.
[ * The birth-rate in Calcutta fell to 9 per 1,000 in July 1898, owing probably to a similar exodus.—J. K. C.]