WHOOPING-COUGH The first description of a. whooping-cough epidemic we owe to DeBaillou (157S) and in the seventeenth century Willis, Sydenham, and others recognized the disease and differentiated it from those symp tomatologically related to it. Whooping-cough has since become an affection common to all latitudes, with a tendency to assume every year in unequal waves an epidemic character. The frequency of epidemics and the opportunity that has existed daily for decades and centuries, to observe the disease; its symptoms, recognizable even by a layman, and the fact that for the purpose of establishing a diagnosis even the recent finer methods of examination may be dispensed these factors have contributed towards advancing the symptomatology and diagnosis of whooping-cough (Biermer, Barthez and Rilliet, Hagenbach, Sticker), whereas its pathogenesis and etiology are still under discussion, in spite of laborious investigations made with modern equipment.
Whooping-cough is a contagious infections disease. The primary symptoms involving the respiratory tract, the transmission of the dis ease through the sputa, and the usually afebrile course in uncomplicated cases might he regarded as criteria of a local infectious disease. But the occurrence of an initial fever wave, which close observation reveals, and which does not run parallel with the respiratory signs, an early inflammatory leucocytosis, the similarity of the initial symptoms to those of other general affections, the permanent almost al ways acquired by those who have had an attack of pertussis, the course and mechanism of the attacks of coughing differing from other condi tions of local irritation of the respiratory mucous and finally certain complications that probably can be accounted for by the action of toxins, justify one in considering whooping-cough as a general infectious disease whose portal of entry and principal symptoms are found in the respiratory tract.
The transmission of the disease from the sick to the well is usually direct and immediate, in a great majority of cases, through the sputum scattered by coughing. A mediate, indirect infection through sputum adhering to clothes, handkerchiefs, playthings, benches, etc., is very rarely met with. The virulency of the sputa, that is to say, the dura bility of the exciting cause, lasts only a short time.
The susceptibility to whooping-cough varies especially with the age of individuals exposed to the danger of infection. Statistics proving the enormous prevalence of pertussis in children justify the designation of whooping-cough as a disease of childhood. Those who have reached the age of puberty are far less susceptible to pertussis than to other acute infectious diseases occurring chiefly in childhood.
A collection of the cases of whooping-cough reported in the city of Vienna, in 1899, 1900 and 1901 as published in the statistical yearbooks, shows: The age before compulsory school attendance is most affected. The susceptibility shared by all children makes every case imported into the family from the school, the nursery, the kindergarten or the public playground a starting-point for a house epidemic likely to attack the youngest of children. The first year of life, as seen from the above statistics, is less often involved than the following, but nevertheless it is to a considerable extent even more than by measles. Whether this is due to a certain lowered susceptibility or to the less frequent contact with other children, especially in cases of first-born, cannot be certainly decided. But that the first few days or weeks of infantile life do not mean immunity from whooping-cough, may be proven by many closely observed cases. Bouchut reports a case in which a newborn child,in fected on the second day, began to cough on the fourth day, and on the eighth day had pronounced paroxysms of whooping-cough. Rilliet and Barthez reported a case of pertussis in a newborn child whose mother had whooping-cough. Watson observed whooping-cough on the first day of life, and I know of a case in a child fourteen clays old. Porak and Durante, during a local epidemic at the Paris Alaternite noticed a lesser disposition to whooping-cough in the prematurely born (10 cases out of 44), but a greater susceptibility in those born at term, mostly fed by different wet-nurses (10 cases out of 14), all these infants being less than one year old. At the other extreme of life, cases of whooping-cough are known to have occurred during old age.