692 A MANUAL OF BACTERIOLOGY 



staeder and Prowazek as Chlamydozoa. Noguchi has cultivated 

 an extremely minute coccoid form. The disease is inoculable on 

 apes and the virus is stated to be a filter-passer. The causative 

 organism cannot yet be said to be known. 



UNDULANT FEVER. x Synonyms : Kock, Mediterranean or 

 Malta fever. A disease met with especially on the Mediterranean 

 littoral, but also in South Africa, India, China, the Philippines, 

 and the subtropical countries of America, and clinically often 

 simulating typhoid fever. 



A minute organism, commonly called a micrococcus, but 

 probably a small bacillus (M. or B. melitensis), first described by 

 Bruce, is the cause of the disease. The organism seems to be 

 closely allied to the B. abortus culturally and serologically ; the 

 two organisms show cross- agglutination. This fact may explain 

 why the serum of some cows agglutinates M . melitensis, as shown 

 by Kennedy. 



Microscopically, the organism from young cultures occurs as a 

 coccus, single, in pairs, or in short chains, though in older cultures 

 bacillar forms are seen ; it is easily stained by the ordinary anilin 

 dyes, but is Gram -negative. In hanging-drop cultures it shows 

 an active Brownian movement, but probably not true motility. 

 The organism may be isolated from the blood during life and from 

 the spleen of a cadaver. 



On agar it grows as minute transparent colonies, which first 

 appear when inoculated from the spleen in ninety to 125 hours. 

 In thirty-six hours more the colonies become amber-coloured, and 

 later still, in four to five days, they become opaque, of a slightly 

 orange colour, and round with granular margins. On gelatin a 

 whitish growth slowly forms without liquefaction, and in broth a 

 diffused cloudiness forms, with a white deposit and without film- 

 formation. Litmus milk becomes alkaline without curdling. 

 Alkali is also produced in glucose media, but galactose, maltose, 

 and saccharose are unchanged (see table, p. 302). The distribu- 

 tion of the M. melitensis in the body corresponds closely with 

 that of the B. typhosus ; thus it is abundant in the spleen, rela- 

 tively scanty in the blood, and is excreted in the urine. 



The M. melitensis maintains its vitality outside the body in 



1 See Reports of the Mediterranean Fever Commission (Royal Society), 

 pts. i-vii, Harrison & Sons, 1904-1907. 



