476 THE COCCUS OF MEDITERRANEAN FEVER 



abrasion on the skin (Shaw). It is possible that infection may also take 

 place through dust contaminated with the coccus settling on the nasal or 

 ocular mucous membrane (Shaw) (vide infra experimental inoculation). 

 Zammitt has suggested that mosquitoes may act as carriers of the infection. 



SECTION I. EXPERIMENTAL INOCULATION. 



Man. Intentional or accidental infection of men with cultures of the 

 Micrococcus melitensis has several times been followed after an incubation 

 period of five days to a fortnight by a typical attack of Mediterranean fever. 



Animals. Monkeys and goats are highly susceptible to the disease. 



After sub-cutaneous inoculation of a small quantity of an agar culture 

 rubbed up in a few drops of sterile water monkeys suffer from a disease 

 very similar to that in man. 



At the close of an incubation period of 25 days the temperature rises 2 or 3 C. 

 and is frequently of a daily remittent character ; a period of apyrexia lasting a few 

 days followed by a second rise of temperature often intervenes during the course of 

 the disease. The serum agglutinates the coccus after about the fifth day in dilutions 

 of 1 in 100 to 1 in 1000. The disease may last several months and ultimately end 

 in recovery, but as a rule the animal dies about the end of the second week. Post 

 mortem, the liver and spleen are swollen and yield pure cultures of the micrococcus. 

 There are never any lesions in the Peyer's patches. 



By means of feeding experiments Horrocks and Kennedy infected monkeys 

 and goats, and Shaw produced the disease in monkeys by smearing the nasal 

 and ocular mucous membranes with cultures and infected dust. 



Dogs, horses, asses and mules are also susceptible to infection with the 

 micrococcus. 



Rabbits, guinea-pigs, rats and mice are more immune than the preceding. 

 Durham and Eyre produced a fatal result in these animals by inoculating them 

 intra-cerebrally, and the virulence of the organism is found to be rapidly 

 increased by intra-cerebral passage through rabbits or guinea-pigs. Carbone 

 produced a fatal result in rabbits by intra-venous, and in guinea-pigs by 



intra-peritoneal inoculation ; the guinea-pigs 



% ^ . % : .\ * .;.. suffered from a purulent inflammation of the 



\: ,"* tunica vaginalis accompanied by atrophy of 



:-V- : - . *' *\? thetestes. 



..... ".*, SECTION II. MORPHOLOGY. 



:. - ** 1. Microscopical appearance. 



& .\ : . % . % The Micrococcus melitensis is a rounded or 



V" ./* -' slightly oval bacterium, measuring about O3//, 



] .. J... i* 1 diameter; elongated forms are occasionally 



. "" seen in cultures. The organisms generally 



no. -ZM.~ Micrococcus melitensis. ccur singly or as diplococci but may also form 



Film from an agar culture (24 hours), very short chains. The coccus is regarded as 



Carbol^th 3 nin. (Oc. II, obj. A tfc, non . motilej though p ollaci affirmg ^ it ig 



motile and that it has a single flagellum which 



however is very difficult to stain. Gordon claims to have demonstrated one 

 to four flagella. 



Staining reactions. The coccus stains readily with the ordinary dyes and 

 is gram-negative. 



2. Cultural characteristics. 



Conditions of growth. The Micrococcus melitensis is an aerobic organism. 

 The optimum temperature of growth is 37 C. : at 22 C. the growth is 



