Since 1900 there have been several mild outbreaks of bubonic plague.
One of the results of recent observation is the classification of plague cases under three heads, which have already been mentioned several times: (1) bubonic, (2) pneumonic, (3) septicaemic. (The word " pesti-caemic " is also used instead of " septi-caemic," and though etymologically objectionable, it is otherwise better, as " septicaemic " already has a specific and quite different meaning.) It should be understood that this classification is a clinical one, and that the second and third varieties are just as much plague as the first.
Bubonic plague, to be sure, is a disease.
" It is impossible," writes Sir Richard Thorne (Local Government Board Report, 1898-1899), " to read the medical history of this disease in almost every part of the world without being impressed with the frequency with which recognized plague has been preceded by ailments of such slight severity, involving some bubonic enlargement of glands and some rise in body-temperature, as to mask the real nature of the malady."
It is necessary to say this, because a misleading use of the word " bubonic " has given rise to the erroneous idea that true plague is necessarily bubonic, and that non-bubonic types are a different disease altogether.