Material from ulcers or glands should be inoculated into guinea pigs or white mice. The organism is almost invariably absent from the blood of human cases so that blood cultures or animal inoculation from such blood are almost always negative.
Complement fixation and agglutination tests are the methods of diagnosis to be relied on. In the Hygienic Laboratory an antigen is prepared by washing off the 72 hour growth from egg yolk medium with small amounts of saline. The suspension is heated for 30 minutes at 56°C. and then preserved by the addition of O.3% tricresol. Such an antigen is used for each type of test.
Prognosis
This disease is but rarely followed by death. It is however a most incapacitating disease by reason of the three or four months of convalescence during which time the strength and energy of the patient are markedly affected.
Prophylaxis and Treatment
Prophylaxis.—In view of the very great liability to infection of those carrying on autopsies of animals experimentally infected with the disease it would seem advisable to wear rubber gloves when doing such work. It would appear that house flies, stable flies and horseflies may transmit the disease in nature and we know that bedbugs and lice can transmit the disease among experimental animals. When we consider the natural infection of ground squirrels and jack rabbits in California and Utah and wild rabbits in the middle west, the problem of prophylaxis looms to great proportion.
Treatment.—At present treatment is entirely symptomatic. Those who go to bed at once and remain in bed during the stage of fever seem to be less seriously affected.