Whooping-cough Measles
1807
Nov. 18 2
Dec. 18 1
1808
Jan. 10 2
Feb. 20 2
March 12 5
April 18 71
May 9 259
June 9 260
July 2 118
Aug. 2 32
Sept. 2 22
Oct. 2 10
Nov. 4 4
Dec. 2 2
1809
Jan. 7 4
Feb. 6 4
March 7 2
April 16 1
May 22 4
June 25 4
July 22 6
Aug. 15 2
Sept. 35 4
Oct. 23 1
Nov. 36 2
Dec. 45 10
1810
Jan. 33 4
Feb. 32 4
March 19 3

Whatever correspondence or relation there may be between measles and whooping-cough, (and it has been remarked by many in the ordinary way of experience), it eludes the method of statistics[1244]. As for the catarrhs of infants and children other than those which are part of the actual attack of measles or influenza, they are so common from year to year, and even from month to month, (perhaps coincident with teething, or with chicken-pox or other slight febrile disturbance), that a statistical study of whooping-cough in relation to them could lead only to an empirical, and possibly bewildering, result. It may be more useful to consider the antecedent probability of some such relationship, arising out of the pathology of the convulsive cough.

Whooping-cough is not only a paroxysmal cough coming on in convulsive fits at intervals, but the paroxysms, as they recur for many weeks, or, as they say in Japan, “for a hundred days,” have none of the obvious occasions of coughing, such as catarrh of the mucous membrane, congestion of the lungs from hot or close air, irritation of the bronchial tubes from dusty particles or vapours, or the presence of tubercles in the substance of the lungs. Such irritants can, indeed, produce whooping-cough, as in the following instance of “artificial chincough” related by Watt:

Two children having quarelled in their play, one of them thrust a handful of sawdust into the mouth of the other. Some of the sawdust passed into the windpipe. After a short time the child began to have violent convulsive fits of coughing, in which the whoop was very distinctly formed. Expectoration in the course of a few hours removed all the irritation, and the coughing thereupon ceased.

But in natural or ordinary whooping-cough there is no mechanical irritation, there is nothing to cough up, the reflex action, violent and paroxysmal though it be, has apparently no motive. I have, in another work, offered an original explanation of the paroxysmal cough of children as being the deferred reaction, the postponed liability, the stored-up memory, of some past catarrhal or otherwise irritated state of the respiratory organs, to which I refer without attempting to summarize it here[1245].

The epidemicity of whooping-cough presents no more difficulty if the malady be viewed as the sequel or dregs of something else than if it be taken for an independent primary affection. The many infants and children that suffer from it together may have equally been suffering together from one or other of the various things of which it is assumed to be the sequel—influenza, measles, sore-throat, the bronchitis of rickets, simple bronchial catarrh of the winter, simple coryza. Again, it may be a secondary or residual affection with many, but a communicable disease to others. Much of the whooping-cough of an epidemic is believed by good authorities, such as Bouchut and Struges[1246], to be simply mimetic, or a habit of coughing acquired by hearing other children coughing in a particular way, just as chorea is sometimes acquired in schools or hospital-wards through the mere spectacle of it. But it may be doubted whether much of the whooping-cough which swells the bills of mortality is acquired in that way. The children that die of it are probably most of them such as had only escaped dying of the measles or other infective disease, or of the non-specific catarrh, which had preceded the whooping-cough.

CHAPTER VII.

SCARLATINA AND DIPHTHERIA.