VARIOLA AND VARICELLA 551 



The failure to isolate a bacterial form has induced many 

 observers to seek for a parasitic protozoon in variola and 

 vaccinia. L. Pfeiffer in 1887 observed roundish or ovoid 

 bodies in the lymph in both diseases, which he regarded 

 as sporozoa. Guarnieri found small bodies, about half 

 the size of the nucleus, in the epithelial cells of the skin 

 in the prepustular stage of variola (Cytoryctes variola). 

 Small shining amoeboid bodies were also noticed in the 

 epithelial cells of the corneae of guinea-pigs inoculated 

 with vaccine lymph. L. Pfeiffer confirmed Guarnieri's 

 work, and also described these amcebiform parasites in 

 the blood in variola and vaccinia, and of vaccinated calves. 

 J. Clarke, and RutTer and Plimmer in this country described 

 somewhat similar appearances. Ruffer and Plimmer 

 describe the supposed protozoon as a small round body, 

 about 3 JUL in diameter, lying within a clear vacuole in 

 the protoplasm of the epithelial cell. 



Councilman, Magarth, Brinkerkoff, Tyzzer, and Calkins l 

 in America have found the Guarnieri body in variola and 

 vaccinia in man and animals, and regard it as a protozoon 

 and the causal agent of these diseases. 



Ogata found bodies which he regards as parasitic pro- 

 tozoa and the causative agent of the disease in variolous 

 and vaccine lymph. Reed likewise observed small granular 

 amoeboid bodies having a diameter of about one-third 

 that of a red blood- corpuscle, similar apparently to those 

 described by L. Pfeiffer, in the blood of vaccinated children 

 and monkeys, but also observed them and this is impor- 

 tant occasionally in the blood of normal children and 

 monkeys. 



Funck, Roger and Weil, and Calmette 2 have also 

 observed various bodies and retractile granules in lymph. 



1 Journ. Med. Research, vol. xi, 1904, p. 173 -^Philippine Journ. of 

 Science, vol. i, 1906, p. 239. $& ; 1*\ 



2 Ann. de Vlnst. Pasteur, xv,jl901. No. 3, p. 161, 



