ON THE SUBJECT OF PLAGUE 
879 
mild form of bubonic plague, and Pestis major , which is a 
severe form. The latter is further subdivided into a number 
of varieties. Where the plague bacilli are found chiefly in 
the glands, we call it bubonic plague ; when in the lungs, 
pneumonic plague ; when as a general septicaemia, septicaemia 
plague. But it must be remembered that all forms have a 
common cause — the Bacillus pestis. 
Pestis major . — The incubation period in Pestis major is 
generally from three to five days. It may be more. The onset 
is sudden, and the patient may suffer from headache, giddiness, 
and a staggering gait. He soon gets a thick, slow mode of 
speech. The temperature rapidly rises from 102° to 104° F., 
and even higher. The pulse also is rapid, from 90 to 180 ; the 
normal rate being about 75. The temperature lasts two to 
five days. The lymphatic glands are enlarged, and in the 
majority of cases those in the groins are affected. The en- 
largement of these may indeed be the first symptom noted ; 
but usually they occur after the commencement of the fever. 
They are very painful, and at first very hard. If they go on 
to suppuration, it is considered a favourable sign ; but if, on the 
other hand, rapid softening, flattening, or disappearance of 
the bubo takes place during the height of the fever, it generally 
means that the patient will succumb. In severe cases 
haemorrhage from various organs may be observed : thus 
bleeding from the nose or lungs may be seen ; and the latter is 
characteristic of the pneumonia variety of the disease. 
The duration of the attack is usually from three to five 
days, in fatal cases ; but it may be very much shorter than 
this, even to sudden death. 
The mortality in plague varies. During the height of the 
epidemic it is often 80 to 90 per cent. In India the general 
case mortality has been 70 to 85 per cent. In Hong-Kong 
it was 89 to 96 per cent, in Chinese ; but was less among the 
Indians there, 77 per cent., and still less among the Japanese, 
60 per cent. In South Africa it was 66 per cent, for the coloured 
population. Among Europeans it appears to be much less : 
thus in Hong-Kong it was only 34 per cent., in Bombay 30 
to 40 per cent., and in Capetown 33 per cent. The percentage 
of deaths may tail off at the end of the epidemic season. 
