Essays in preventive medicine : the health of children, and the period of infection in epidemic diseases / by William Squire.

  • Squire, William
Date:
1887
Catalogue details

Licence: Public Domain Mark

Credit: Essays in preventive medicine : the health of children, and the period of infection in epidemic diseases / by William Squire. Source: Wellcome Collection.

    62/132 (page 56)
    these diseases, but not with that definite and scientific pre- cision which is to be sought for in each special disease of the class, and which must be reached before such general conviction as is alone conducive to useful action can result. Excepting mere conveyance, diseases are not communicable by personal infection until they have themselves been re- ceived by the infecting person ; nor when received are they immediately communicable, unless certain local effects from contagia, coming before any general illness and even without being followed by any, may give rise to infection ; for it may be stated generally that an interval must elapse before in- fection received can be again propagated. This period, of longer or shorter duration for different diseases, nearly without symptoms and probably non-infec- tious, is the stage of latency; then, with the earliest symp- toms, commences the stage of invasion. Febrile movement is now progressive and continuous, so that it cannot be stopped or averted ; the disease-germ multiplies, products of the diseased action are formed, and infection begins. This point is marked by elevation of temperature, easily recognised by the thermometer; it is often preceded by an equally recognisable thermometric depression, analogous to the shock after injuries, marking the first effects of the poison. Until now the attack might have aborted ; this is one mode of escape from the diseases we most frequently en- counter. Abortive attacks afford no protection against the liability to a subsequent infection ; they sometimes procure a temporary immunity where a continuous exposure to an infection has reduced susceptibility; more frequently some premonitory symptoms appear and disappear after a short or casual exposure. Some few diseases, at first local, where the early manifestations are under control, may be aborted by direct treatment. But it is a grave mistake to trust to local treatment in a general disease, Diphtheria, for in- stance ; it is an error to suppose scarlet-fever or measles can be lessened by emetics or aperients clearing away morbid matters ; no increase of the ordinary secretion of the body can eliminate the poison or germ of these diseases; the more intense the disease the greater the specific product, and the greater the risk to all. The disease once set up is, from first to last, an elimination of itself in its own form and manner ; which self-elimination, the sign of the disease, is the very source of infection, and the basis of the axiom that infection begins as soon as the disease.