Student's textbook of hygiene / [William James Wilson].

  • Wilson, William James.
Date:
[1915]
Catalogue details

Licence: Public Domain Mark

Credit: Student's textbook of hygiene / [William James Wilson]. Source: Wellcome Collection.

    214/316 (page 180)
    in harmony with the clinical fact that the disease is most readily communicable at this stage. The disease is conveyed by particles of infected mucus from mouth and throat. The bacillus is very delicate, and it is therefore unlikely that fomites ever convey infection. The preventive measures are similar in the case of Measles and Whooping-Cough. Influenza resembles Measles and Whooping-Cough in being so infectious at an early stage that, so far, preventive measures capable of controlling the spread of the disease have not been discovered. The disease is due to a small Gram-negative bacillus (Pfeiffer’s bacillus), which grows best on media con- taming hemoglobin. The bacillus readily dies out, so that clothing is unlikely to convey the disease. The bacillus is found in the nose, throat, and bronchi, so that infection is acquired by inhalation. The disease frequently occurs in pan- demic form, and although not often directly fatal, except in the case of the old and feeble, it causes a high mortality by respira- tory and cardiac complications. During an epidemic, old people should avoid travelling or attending meetings. Pneumonia is second only to Tuberculosis as a cause of death in the United Kingdom. In 1911, 37,642 deaths were attrib- uted to this disease. As well as being a direct cause of death, Pneumonia is a frequent complication of other diseases—e.g., Measles, Whooping-Cough, Influenza. In the great majority of cases the infective agent is the capsulated lanceolate Gram- positive diplococeus of Fraenkel. This micro-organism is fre- quently found in the throat of healthy persons, but there is evidence that the strains isolated from cases of Pneumonia and from persons in contact with them are more virulent than the normal saprophytes of the throat. Predisposing conditions of infection are chills following ex- posure to inclement weather. The greatest prevalence of Pneumonia occurs at the season of most rapid and sudden changes of the temperature, which is most often in the early spring, but may be in winter. Weakening of the system by malnutrition, alcoholism, and by the poison of various diseases favours the development of Pneumonia. The lowering of the resistance of the individual is probably a more important factor than the presence in the throat of the infective agent in the