It is possible that a child may become affected with pertussis second time—an interval of complete health extending over years preclud ing a relapse of the first affection—but in such an event, the course of the disease is rapid and light.
a descrip tion of the normal process of whoop ing-cough the hitherto usual distinction of the several stages may be retained with advantage, although a strict separation of the phases in a given case is frustrated by the frequent exacerbations and complications. We may retain the customary division into three stages, with a slightly characterized prelude of prodromal symptoms, such as lassitude, head ache and disturbed sleep.
The first or catarrhal stage sets in with symptoms of an acute catarrhal affection of the respiratory organs, sneezing, conjunctival irri tation, more or less severe cough, and sometimes with slight fever. Now and then a slight, enanthema-like injection of the palate and palatal arches is noticed. In this stage, as a rule, every auscultatory sign of bronchitis is wanting. In younger children, especially in such as in cline to false croup, an attack of acute laryngitis may abruptly open the scene and in the next few days subside to the usual catarrhal symp toms. For one or two weeks, the temperature being normal and the general condition relatively good, the cough increases, becomes spas modic, 'choking, more frequent by night than by day, and gradually assumes the typical character of the whooping-cough paroxysms. Thus the catarrhal phase quite gradually glides into the convulsive stage. This first period of whooping-cough lasts one to two weeks, usually from seven to ten days.
While in the first phase of pertussis, especially during the first days, we find in the symptoms nothing characteristic of the disease and we are left in doubt as to the diagnosis; so that in the end only a positive history of exposure or the inefficiency of narcotics direct our suspicion to whooping-cough. The peculiarities of a single paroxysm and the ob jective results of an examination in the second or convulsive stage, will secure a positive diagnosis. The attacks occur either spontaneously or may be aroused by a variety of causes, such as emotion (anger, laughing, weeping), reflex acts (singultus, sneezing), swallowing of solid morsels, more copious meals, a draught of cold water, an air current, visual and auditory impressions (glaring light, shrill sounds), seeing or hearing of a whooping-cough paroxysm in another child. Spontaneously the
paroxysms occur also during sleep, by night even more frequently than by clay.
Older children, able to relate their sensations, describe aura-like prodromes introducing the paroxysm, as tickling or scratching in the throat, choking, eructation, suffocating distress, pressure behind the sternum, intense anxiety. Thesc sensations impel the children to run to the mother, take hold of solid