Hostname: page-component-78c5997874-4rdpn Total loading time: 0 Render date: 2024-11-05T05:39:14.875Z Has data issue: false hasContentIssue false

The Virulence Testing of the Diphtheria Bacillus and its Practical Application

Published online by Cambridge University Press:  15 May 2009

C. C. Okell
Affiliation:
The Wellcome Physiological Research Laboratories.
H. J. Parish
Affiliation:
The Wellcome Physiological Research Laboratories.
Rights & Permissions [Opens in a new window]

Extract

Core share and HTML view are not available for this content. However, as you have access to this content, a full PDF is available via the ‘Save PDF’ action button.

1. In the intradermic test virulence of “morphological diphtheria bacilli,” 0·2 c.c. containing 100 million organisms is injected. The control guinea-pig receives 500 units of antitoxin the night prior to the test. The test animal receives 125 units six hours after the injection of the cultures. A known virulent organism is always injected as a control; 12 to 20 cultures can be tested on one guinea-pig.

Of 2368 swabs received, 1388 (59 per cent.) showed morphological C. diphtheriae. Fromthese 1286 pure cultures were isolated (92·7 per cent.). In 234 positive swabs from cases of clinical diphtheria, in a series examined under very favourable conditions, morphological C. diphtheriae were obtained in 231 (98·7 per cent.) and of these 229 (99·1 per cent.) were virulent. In 758 positive cultures from carriers morphological C. diphtheriae were isolated in 715 (94 per cent.); 50 per cent. were virulent C. diphtheriae, 39 per cent. avirulent, 3·6 per cent. of Hofmann group, 0·3 per cent. Xerosis and 6.4 per cent. unclassified diphtheroids.

3. Only one culture of intermediate virulence was found, i.e. uncertain reactions occurred with a dose of 100 million organisms while clear reactions occurred with 1000 million.

4. Out of 626 positive cultures from cases of diphtheria, both virulent and avirulent bacilli were isolated in two instances, once from the throat and once from the nose.

5. A monovalent antitoxin (Park Williams 8) nenutralised all of 819 virulent strains.

6. Amongst 39 cultures obtained from the ear in post-diphtherial conditions, virulent C. diphtheriae were isolated fourteen times.

7. Impure primary (“field”) cultures gave reliable results (94 per cent.) when more than one-third of the organisms seen in the smear made from the overnight culture were morphologically C. diphtheriae. If fewer C. diphtheriae were present in the smear th e primary culture gave uncertain results.

Type
Research Article
Copyright
Copyright © Cambridge University Press 1926

References

REFERENCES

Bull, C. G. and Mckee, Clara M. (1923). The Whole Culture Method of Testing the Virulence of Diphtheria Bacilli. Am. Journ. Hyg. iii. 103.Google Scholar
Caiger, F. Foord and O'brien, R. A. (1924). Observations on the Diagnosis of Diphtheria. Lancet, ii. 53.CrossRefGoogle Scholar
Eagleton, A. J. and Baxter, E. M. (1921). The Virulence of Diphtheria-Like Organisms. Brit. Med. Journ. i. 775.CrossRefGoogle Scholar
Eagleton, A. J. and Baxter, E. M. (1922). The Virulence of Diphtheria-Like Organisms. (Further note.) Brit. Med. Journ. i. 139.CrossRefGoogle Scholar
Forbes, J. Graham (1923). The Problem of the Diphtheria Carrier in London Children of School Age. Public Health, xxxvi. 323.Google Scholar
Force, J. N. and Beattie, Margaret I. (1922). An Intracutaneous Test for the Virulence of Diphtheria Bacilli in Field Cultures. Am. Journ. Hyg. ii. 490.Google Scholar
Havens, L. C. and Powell, H. M. (1922). The Use of the Original Diagnostic Culture for the Determination of Virulence of Diphtheria Bacilli. Am. Journ. Hyg. p. 234.Google Scholar
Kelly, F. L. and Potter, A. (1923). Administrative Value of Virulence Test for Diphtheria Bacilli, with Report on Use of Field Cultures. Journ. Amer. Med. Assoc. lxxxi. 734.CrossRefGoogle Scholar
Nuttall, G. H. F. and Grahamsmith, G. S. (1908). The Bacteriology of Diphtheria. (Cambridge.)Google Scholar
O'Brien, R. A. (1924). Diphtheria: Problems in Connection with the Schick Test and Active Immunisation. Journ. Boy. Sanit. Institute, xlv. 84.Google Scholar
Okell, C. C. and Baxter, E. M. (1924). The Fermentative Reactions of the Diphtheria Bacillus. Journ. Path, and Bad. xxvii. 439.CrossRefGoogle Scholar
Okell, C. C., Eagleton, A. J. and O'brien, R. A. (1924). The Rapid Control of Diphtheria Outbreaks in Institutions. Lancet, i. 800.CrossRefGoogle Scholar
Powell, H. M. (1923). A Biological Study of the Diphtheria Bacillus. Am. Journ. Hyg. iii. 109, 357, 923.Google Scholar

A correction has been issued for this article: