Use of Chinese Hamster for Testing the Virulence of C. Diphtheriae

Abstract

Discussion and Summary

The experiments demonstrate that hamsters react much in the same way as guinea pigs to cultures of C. diphtheriae or of diphtheriae-like organisms. There was complete agreement in 95 out of 102 instances. To use hamsters instead of guinea pigs possessed the advantage of giving clear-cut results because these animals invariably died from the virulent organisms and survived the non-virulent ones. Equivocal results from intradermal tests on guinea pigs due to secondary infection from field cultures, or to injections being made too deep into the skin, could thus be avoided.

Other advantages are that 10 hamsters may be purchased for the cost of one guinea pig, and that the control hamsters require much less antitoxin. Objections may be raised in that pure cultures are necessary, thereby causing possible delay. This is only of theoretical interest, because usually it is only in doubtful and convalescent cases of diphtheria that this test is required, and a delay of one day does not limit its usefulness. Furthermore, one must remember that in making the conventional test on guinea pigs a delay of 24 hours is also necessary after the control guinea pig has received antitoxin.

As a result of these studies it has been shown that Chinese hamsters are suitable animals for the routine determination of the virulence of C. diphtheriae. The use of these animals instead of guinea pigs is very much less expensive and in certain respects gives more reliable information.