570 SMALLPOX AND VACCINATION 



gave cultures on ordinary media. It was, however, still potent 

 to produce vaccinia.) 



Klein and also, independently, Copeman, have observed an organism 

 in lymph taken from a vaccine pustule in a calf on the fifth and sixth 

 days, in human vaccine lymph on the eighth day, and in lymph from 

 a smallpox pustule on the fourth day. To demonstrate the bacilli, 

 cover-glass films are dried and placed for five minutes in acetic acid (1 

 in 2), washed in distilled water, dried, and placed in alcoholic gentian- 

 violet for from twenty-four to forty-eight hours, after which they are 

 washed in water and mounted. Copeman and Kent also found the 

 bacilli in sections of vaccine pustules stained by Loffler's methylene-blue, 

 or by Gram's method. The organisms are *4 to '8 /UL in length, and 

 one-third to a half of this in thickness. They are generally thinner and 

 stain better at the ends than at the middle. They occur in groups of 

 from three to ten in both the lymph and the tissues. In the centre of 

 their protoplasm there is often a clear globule, which is looked on as a 

 spore. They have hitherto resisted the ordinary isolation methods, a 

 fact which is rather in favour of their non-saprophytic nature. By 

 inoculating fresh eggs with the crusts of smallpox pustules Copeman. has, 

 however, obtained a growth of a bacillus resembling that found by him 

 in the tissues. Though subcultures on ordinary media have been 

 obtained, the pathogenic effects of these have not been fully investigated, 

 and thus the identity of this bacillus with that seen in the tissues is 

 not proved. 



Various observers have described structures in the epithelial 

 cells in the neighbourhood of the smallpox or vaccine pustules, 

 which they have interpreted as being protozoa. Thus Ruffer 

 and Plimmer describe as occurring in clear vacuoles in the cells 

 of the rete Malpighii at the edge of the pustule (in paraffin 

 sections of vaccine and smallpox pustules carefully hardened in 

 alcohol, and stained by the Ehrlich-Biondi mixture) small round 

 bodies of about four times the size of a staphylococcus pyogenes, 

 coloured red by the acid fuchsin, sometimes with a central part 

 stained by the methyl-green. These are described as multiplying 

 by simple division, and in the living condition exhibiting 

 amoeboid movement. Similar bodies have been described by 

 Reed in the blood of smallpox patients and of vaccinated 

 children and calves. 



These are probably the bodies described by Guarnieri and to 

 which considerable attention has been paid. They are from 

 1 to 8 /A in diameter, are round, oval, or sickle-shaped, and stain 

 by ordinary nuclear dyes. They lie in the cells in spaces 

 often near the nucleus, and are readily demonstrable in vaccine 

 pustules and also in the experimental lesions which can be 

 produced in the rabbit's cornea, the larger bodies being denned 

 in the cells towards the centre of the lesion. These bodies 



