The prevention of infection in public vehicles / by Alfred Greenwood.

  • Greenwood, Alfred.
Date:
1902
Catalogue details

Licence: In copyright

Credit: The prevention of infection in public vehicles / by Alfred Greenwood. Source: Wellcome Collection.

Provider: This material has been provided by London School of Hygiene & Tropical Medicine Library & Archives Service. The original may be consulted at London School of Hygiene & Tropical Medicine Library & Archives Service.

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    atmosphere, and breathed by other people who are healthy. These bacilli retain their vitality for much longer periods when enclosed in places such as public vehicles than when they are present in open spaces. Tavo German observers named Schiff and Fisher have proved conclusively that dried tuberculous spittle remains infected for many months, provided it is not exiDosed to an excess of direct sunlight. Also Dele- pine has proved that the tubercle bacilli Avill grow at an ordinar}^ temperature the whole year round. Therefore the danger of allowing dust to accumulate in public vehicles for long periods is very great. Sun- light cannot exert its germicidal action upon germs which are contained in dust beneath the seats and in the upholstering of the vehicles. Also low tempera- tures merely inhibit the development of the tubercle bacillus, but its vitality remains unimpaired after exposure to intense cold or prolonged freezing and thawing. The bacilli may be present in the dust in enormous numbers, and Heller has calculated that the number of tubercle bacilli expectorated daily by a consumptive patient amounted on an average to 7,200,000,000. Some idea of the size of the bacilli may be gained from the following facts:—If a row is formed of them, placed in a line so as to make a length of lin., there will be some 3500 in the inch, or if placed side by side so as to make a row lin. long, there will be some 85,000 of them.
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