London's Pulse: Medical Officer of Health reports 1848-1972
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Hints from the Health Department. Leaflet from the archive of the Society of Medical Officers of Health. Credit: Wellcome Collection, London
London County Council 1899
[Report of the Medical Officer of Health for London County Council]
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The results obtained were as follows—
| Date of inoculation of peptone solution. | Date of examination of peptone culture. | Descriptive number of cultures. | Remarks. Results of the examination of the peptone cultures. |
|---|---|---|---|
| 1898. October 26... (Immediately after the inoculation of the sewage with Koch's vibrio.) . | 1898. October 27 | (1) | Cholera vibrios present in great abundance. |
| October 27 | „ 28 | (2) | A positive result was obtained only with difficulty. |
| „ 28 | „ 29 | (3) | Vibrios found without difficulty. |
| „ 31 | November 1 | (4) | „ |
| November „ 1 | „ 2 | (5) | Only a few vibrios could be found. |
| „ 2 | „ 3 | (6) | A positive result was obtained without much difficulty. |
| „ 3 | „ 4 | (7) | Vibrios found without any difficulty. |
| „ 4 | „ 5 | (8) | A positive result was obtained but only after prolonged searching. |
| „ 9 | „ 10 | (9) | The result was negative. |
| „ 18 | „19 | (10) | „ „ |
| „ 24 | „ 25 | (11) | „ „ |
| December 5 | December 6 | (12) | „ „ |
In this experiment, as in experiment 1, there was a difficulty experienced in finding the
cholera bacillus in the peptone culture number (2) made only the day after inoculation. Yet in
both experiments no difficulty was experienced in arriving at a positive diagnosis as regards
number (3) peptone culture. Notwithstanding the enormous number of vibrios added to the
sewage, they appeared to die out much sooner than in the preceding experiment.
Speaking in general terms, and dealing with both experiments, it may be said that under
the above conditions of experiment the cholera bacillus may lose its vitality in less than a fortnight
(experiment 2) or remain viable for nearly four weeks (experiment 1) when added to
Crossness crude sewage.
(b) Vitality of B. Prodigiosus in Crossness Crude Sewage.
Experiment 3, October 24th, 1898.
In this experiment 10 c.c. of Crossness crude sewage were inoculated with B. prodigiosus
(platinum loopful from a young agar culture). Although this micro-organism is occasionally met
with in sewage it is very rare in London raw sewage, and so is to be regarded as being in a sense
an intruder. The tube containing the raw sewage (†B. prodigiosus) was kept in a dark cupboard
at the room temperature.
In seeking to determine the lviability of this microbe in the sewage the following plan was
adopted—From time to time a loopful of the sewage (+ B. prodigiosus) was taken and rubbed over
the sloping surface of oblique agar tubes. These were kept at the room temperature, and the
presence of B. prodigiosus was readily detected by the bright red colour produced by the growth
of this microbe in agar cultivations.
The results obtained are shown in the following Table—
| Date of inoculation of the oblique agar tubes. | Descriptive number of cultures. | Results. As regards red growth on oblique agar tubes. |
|---|---|---|
| 1898. October 24 (Immediately after the inoculation of the sewage withD. prodigiosus). | (1) | Positive. |
| October 25 | (2) | „ |
| „ 26 | (3) | „ |
| „ 27 | (4) | „ |
| „ 28 | (5) | „ |
| „ 29 | (6) | „ |
| „ 31 | (7) | „ |
| November 1 | (8) | (only a few colonies). |
| „ 2 | (9) | „ „ |
| „ 3 | (10) | „ „ |
| „ 4 | (11) | „ „ |
| „ 5 | (12) | „ (only 3 colonies). |
| „ 7 | (13) | „ (only 1 colony). |
| „ 9 | (14) | „ „ |
| „ 12 | (15) | Negtaive |
| „ 14 | (16) | „ |
| „ 16 | (17) | „ |
| „ 18 | (18) | „ |
| „ 25 | (19) | „ |
| December 3 | (20) | „ |
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