Читать книгу Epidemic Respiratory Disease. The pneumonias and other infections of the repiratory tract accompanying influenza and measles онлайн

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It seems better, therefore, to consider influenza first as a disease by itself and subsequently to take up the question of pneumonia and the relation of influenza to it.

The most striking clinical features of influenza are its epidemic character, its involvement of the respiratory tract, its extremely prostrating effect, and the often surprising rapidity with which the individual cures himself. These features strongly suggest that the etiologic agent of the disease is an organism subject to rapid changes in virulence; that it is confined to the respiratory tract where it produces a superficial inflammatory reaction giving rise to the characteristic symptoms of coryza, pharyngitis and tracheitis; that it elaborates a poison, possibly a true toxin, readily absorbed by the lymphatics, the effect of which is manifested in the profound prostration, severe aching pains, erythema, and leucopenia; and that it may either disappear promptly from the respiratory mucous membrane at time of recovery or may persist, leading a relatively saprophytic existence for an indefinite period of time, being no longer harmful to the individual, at least more than locally, because of an acquired immunity. Furthermore, in our opinion, the very brief incubation period suggests that the disease is bacterial in origin, rather than that it is analogous to the exanthemata, the majority of which present a comparatively long, fairly constant, incubation period.