CHAPTER VII 



SMALL-POX AND VACCINIA 



THE modern pathology of variola and its modified form vaccinia 

 began in 1892, when Guarnieri described as protozoa small hyaline 

 bodies that occur in certain stages of the lesions of small- pox and 

 in the epithelial cells of the cornea of rodents after inoculation with 

 active vaccine. These bodies l Guarnieri named Cytoryctes variola, 

 believing them to be protozoa which invade and destroy the cells 

 of their host. He described amoeboid movement, and binary and 

 mulberry-like division in the bodies. A photograph of these bodies, 

 as seen in a stained preparation of a rabbit's cornea forty-eight hours 

 after vaccination, is shown in Fig. n. If the simple experiment is 

 done with ordinary skill and care, the appearance of Guarnieri's 

 bodies after inoculation of a rabbit's cornea is certain when active 

 vaccine lymph or the fresh juice of a variolous lesion is used. The latter 

 fact makes the experiment an invaluable one for the diagnosis of doubt- 

 ful cases of small-pox. Sections may be examined, either unstained, or 

 stained with any good tissue-stain. L. Pfeiffer, who had been at work 

 at the investigation of small-pox and allied subjects for many years, 

 confirmed 2 Guarnieri's account. He described their amoeboid move- 



1 Weigert and Renault had previously described the bodies, but without any 

 interpretation of their nature. Before Guarnieri, Griinhagen had described 

 greenish, highly refracting corpuscles, and van der Loeff, in 1887, had described 

 amoeboid organisms in variolous and vaccine lymph. 



2 L. Pfeiffer, ' Behandlung und Prophylaxe der Blattern,' 1893. The transla- 

 tion is quoted from an article by myself on ' Recent Contributions to the Pathology 

 of Variola,' etc., Medical Press and Circular, July 25, 1894. In that article I 

 mentioned that Dr. Pfeiffer had, at my request, sent me a section of a vaccinated 

 cornea which showed Guarnieri's bodies very clearly. I concluded the same article 



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