Whooping-Cough in Modern Times.
When the causes of death began to be registered, in July, 1837, whooping-cough was found to have the following relative place among the principal maladies of children during the latter six months of the year in London and in all England and Wales.
Mortality by diseases of Children, last six months of 1837.
| London | England and Wales | |||
| Convulsions | 1717 | 10729 | ||
| Measles | 1354 | 4732 | ||
| Whooping-Cough | 1066 | 3044 | ||
| Smallpox | 763 | 5811 | ||
| Scarlatina | 418 | 2550 |
Throughout the whole registration period, whooping-cough has kept its place steadily among the chief causes of infant mortality, neither decreasing nor increasing notably in the successive periods from 1837 to the present time. Its mortality has varied a good deal from year to year, owing to occasional great epidemic years such as 1866 and 1878; but on the mean annual average of decennial periods, it has varied little:
Annual Deaths by Whooping-cough per million living at all ages.
| Males | Females | Both sexes | ||||
| 1851-60 | 460 | 545 | 503 | |||
| 1861-70 | 487 | 566 | 527 | |||
| 1871-80 | 474 | 547 | 512 | |||
| 1881-90 | — | — | 451 |
No other epidemic malady has shown the same excess of female deaths in proportion to the numbers of the sex living, diphtheria being the only other that shows an excess at all.
The excess of deaths by whooping-cough among female infants was roughly shown by Watt in 1813, viz. 975 females to 842 males in the registers of the Glasgow High Church, College Church and the North-Western Cemetery, the relative numbers of the sexes living at the respective ages being then unknown. In all Scotland in 1889 the ratio was 1043 male deaths to 1225 female. The singular difference between the sexes in this respect is almost certainly related to the corresponding differences in the formation and development of the larynx, the organ which gives character, at least, to the convulsive cough of children. The expansion of the larynx in boys, which becomes so obvious at puberty and remains so distinctive of the male sex, is one of those secondary sexual characters which begin to differentiate quite early in life, and are probably congenital to some extent. It is not known whether female children are more often attacked than males; but it is probable that they are predisposed both to acquire coughs of the convulsive suffocative kind and to have their lives shattered by the attack—for the same anatomical and physiological reasons, namely, the imperfect development of the posterior space of the glottis with the spasmodic closure by reflex action[1242]. The deaths have been nearly all under the age of five.
Deaths by Whooping-cough per million living at the respective age-periods.
| 0-5 | 5-10 | |||
| 1851-60 | 3624 | 174 | ||
| 1861-70 | 3766 | 152 | ||
| 1871-80 | 3652 | 135 |
These proportions are almost the same as those given by Watt in 1813 from three of the Glasgow registers.
| Period | Deaths by whooping-cough | Under five | Five to ten | Above ten | ||||
| 1783-1812 | 1817 | 1713 | 98 | 3 |
Most of the deaths are in the first year, and in a rapidly declining ratio until the fifth, according to the following rates per million of male children living at each age-period (these figures are for a single year, 1882):
| Under one | One to two | Two to three | Three to four | Four to five | ||||
| 3039 | 2115 | 826 | 433 | 248 |
The mortality from whooping-cough falls very unequally on town and country. Thus, in Scotland in 1889, it caused 2268 deaths, being 3·13 per cent. of the deaths from all causes, and equivalent to a rate of ·58 per 1000 living. The death-rate varied as follows: ·91 in the eight principal towns, ·46 in the group of large towns, ·45 in the group of small towns, ·25 in the mainland rural districts, and ·08 in the insular rural districts. In England, the capital has more than its share of deaths from whooping-cough, Lancashire coming next, while the death-rates of Monmouthshire, Cornwall and Warwickshire are also a good deal above the mean of the whole country. The lowest death-rates are found in the purely agricultural counties.
During the last half-century there has been a decline in the death-rate from all causes, including the infectious diseases as a group; but it can hardly be said that whooping-cough has had a due share in this decline. Notably in Ireland, where the decline of infectious disease has been most marked, it has been, as it were, pushed to the front of its class by the shrinkage of the other items. In Scotland it is now decidedly at the head of the list, and in England it has shared the first place with measles since the great diminution of scarlatina deaths.
Annual average Death-rates per 100,000 living.
| Whooping-cough | Measles | Scarlatina | |||||
| England | 1871-80 | 51·2 | 37·7 | 71·6 | |||
| 1881-90 | 45·1 | 44·1 | 33·8 | ||||
| Scotland | 1871-80 | 63·1 | 37·0 | 79·5 | |||
| 1881-90 | 60·7 | 38·3 | 28·8 | ||||
| Ireland | 1871-80 | 34·8 | 21·0 | 43·5 | |||
| 1881-90 | 28·5 | 19·2 | 20·8 |
There is a small decrease in the death-rate of whooping-cough within the last decennial period, whereas in that of measles there is a slight increase (except in Ireland). The comparative steadiness of whooping-cough among the causes of death is doubtless owing to the fact that the bulk of its fatalities are among infants, and that there appears to be an irreducible minimum of the deaths from all causes at that age-period.