TYPHOID VIRUS. - 155 



Soluble poisons were prepared by BRIEGER, KITASATO, and 

 WASSERMANN (loc. cit.) by heating the liquid cultures to 80 to 

 90 C. and precipitating with alcohol, and also by concentrating 

 them at 37 C. before the addition of the alcohol. These had 

 slight toxic and immunising properties, while the nitrates were 

 absolutely inactive. SiROTiNiN 1 obtained a poison possessing 

 specific^) activity by filtration, but PFEIFFER and KoLLE's 2 

 results were a direct contradiction of this. BITTER'S 8 prepara- 

 tion was obtained by extraction with concentrated glycerin and 

 evaporation in vacuo at 36 C. 



SANARELLI* cultivated very poisonous typhoid cultures on 

 glycerin bouillon for a month at 36 C., and then sterilised them ; 

 these cultures were frequently rendered more poisonous by intra- 

 peritoneal injection into mice. From them he isolated, by means 

 of maceration for several days at 60 C., a very weak soluble 

 poison which produced specific symptoms in the mucous mem- 

 brane of guinea-pigs and monkeys, especially that of the intestine. 

 The lethal dose for rabbits amounted to 10 c.c. per kilo. There 

 was nothing specific, however, in the symptoms in the case of 

 this animal. 



RoDET 5 found that filtered typhoid cultivations were slightly 

 toxic, causing elevation of temperature and local signs of necrosis ; 

 the residual cells had hardly any poisonous action. Special 

 importance attaches to the results obtained by CnANTEMESSE, 6 

 who obtained a very active typhoid toxine speedily decomposing 

 in the air, by cultivation of the bacilli on an extract of spleen 

 which had been digested with pepsin and again neutralised. 

 Here, too, we find the same behaviour as in the case of cholera, 

 the poison being not completely destroyed at 100 C. i.e., 

 doubtless being converted into a less poisonous, but more stable, 

 modification. It is possible that in this case also we have to 

 deal with toxoids. 



It acts upon susceptible animals, producing drowsiness, para- 



1 Sirotinin, "Die Uebertrag. von Typhusbazillen auf Versuchstiere," 

 Zeit.f. Hyg., i., 465, 1886. 



2 Pfeiffer and Kolle, "Ueb. d. spez. Reaktion d. Typhusbazillen," Ze.it. 

 f. Hyg., xxi., 203, 1896. 



3 Bitter, ' ' Ueb. Festig. v. Versuchstieren geg. d. Intoxikation durch 

 Typhusbazillen,';^^./. Hyg., xii., 298, 1892. 



4 Sanarelli, "Etudes sur la fievre typhoide expe"rim." Ann. Past., viii., 

 193, 1894. 



5 Rodet, " Sur les propriete's toxiques des cultures des bacilles d'Eberth," 

 Soc. Bid., 1., 774, 1898. 



6 Chantemesse, "Toxine typhoide soluble," Prog. Mtd., 1898, 245; id. 

 " Losliches Typhustoxin," Wien. med. Blatter, 1898, 18 et seq. 



