A manual of bacteriology, clinical and applied / by Richard T. Hewlett.

  • Hewlett, R. Tanner (Richard Tanner), 1865-1940.
Date:
1898
Catalogue details

Licence: Public Domain Mark

Credit: A manual of bacteriology, clinical and applied / by Richard T. Hewlett. Source: Wellcome Collection.

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    vaccines is then tested by allowing a drop to run out on to the surface of an agar tube, which is afterwards incubated, and if the contents of the capsvdes prove sterile the vaccine is ready for use. The Dosage and Strength of the Anti-Typhoid Vaccines.—The strength of a typhoid vaccine depends upon the number of bacilli it contains and their virulence. The culture employed was of such a strength that one-fourth tube of a twenty-four hour culture was a lethal dose for a 350 to 400 grin, guinea-pig when inoculated hypo- dermically. The dose of the vaccine varies from one-twentieth to one- fourth of a tube. The latter is a somewhat severe dose for a man and would prove fatal to a 350 grm. guinea-pig. Clinical Symptoms which supervene ujpon the Inoculation of the Anti-Typhoid, Vaccines.—The symptoms are comparatively slight when small doses are used (one-twentieth to one-sixth of a tube), such as tenderness at the seat of inoculation, and two or three hours after inoculation a chilly feeling, slight rise of temperature, and restlessness at night, but these symptoms pass away in about twenty-four hours. With the larger doses all the symptoms are severe, and are described as commencing two or three hours after injection with tenderness, which gradually increases in severity and extends upwards into the armpits and downwards into the groin, a patch of congestion two or three inches in diameter develops round the site of inoculation, and red lines of inflamed lymphatics can be traced extending into the armpits. These symptoms gradually subside in about forty-eight hours. The constitutional symptoms were marked by some degree of faint- ness and collapse, in some cases accompanied by nausea and vomit- ing, which commenced about three to four hours after injection, entire loss of appetite, disturbed sleep, and high temperature, all of which passed off in a few hours. The blood and serum of individuals vaccinated in this way give the Widal reaction in a marked manner. Probably to obtain a complete protection three or four successive vaccinations, with increasing doses, at intervals of one to two weeks, would be advisable. There is practically no risk, and the immunity conferred would probably last for some years. As regards the sphere of application of the anti-typhoid vaccination, it might be expedient in the case of young soldiers or other individuals going abroad to infected districts, for those living in a district visited by an epidemic, or for those in attendance on a typhoid patient. 4. Anti-Plague Vaccine. See p. 267.