558 FILTERABLE VIRUSES 



Landsteiner, Levaditi and Pastia 1 have established the presence of 

 the virus in the tonsils and pharyngeal mucosa of an acute fatal case 

 of infantile paralysis. Flexner, Clark and Fraser 2 have shown defi- 

 nitely that the virus was carried in the upper respiratory mucous 

 membranes of healthy human adults, the parents of a child suffering 

 from an acute attack of the disease. Kling, Wernstedt and Patterson 3 

 claim, on the basis of experimental evidence, that the nasal secretion 

 may also harbor the virus. Neustaedter and Thro 4 have found that 

 the virus may remain viable in dust. The transmission of the virus, 

 therefore, would appear to be largely through the upper respiratory 

 tract. Flexner and Amoss 5 have brought forth experimental evidence 

 to show that the atrium of infection is the upper respiratory mucous 

 membrane, and that the virus travels to the meninges by way of the 

 lymphatics; not, as a rule, through the blood. Available evidence 

 would indicate that insects play no part, or at best, a very minor 

 role in the transmission of the virus. 6 The observations of Flexner 

 and Amoss 7 and of Clark, Fraser and Amoss 8 would indicate that 

 the amount of virus circulating in the blood stream is usually very 

 small, thus suggesting the improbability of insect transmission except 

 in unusual instances. 



A very important advance in the study of the etiology of epidemic 

 poliomyelitis was that of Flexner and Noguchi. 9 Using the technic 

 of Noguchi 10 for the cultivation of Treponemata (unheated ascitic 

 fluid and fragments of sterile rabbit tissue under strictly anaerobic 

 conditions) they obtained minute, slowly growing colonies composed 

 of "globular and globoid" bodies occurring singly, in pairs, masses, 

 and in short chains. The elements measure from 0.15 to 0.3 micron 

 in diameter. Bizarre forms are prone to appear in older cultures. 

 The organisms stain feebly with the Giemsa stain and by Gram's 

 method they stain variably with the latter. The organism has also 

 been demonstrated in tissues by a modified Giemsa technic. The 

 first cultivations upon artificial media are difficult to obtain, but 

 subcultures grow more readily. No action was observed on the 



1 Semaine Medicale, 1911, 296. 



2 Jour. Am. Med. Assn., 1913, Ix, 201. 



3 New York Med. Jour., 1911, xciv, 813. 



4 Ztschr. f. ImmunitatsforscH., 1911, xii, 316, 357; 1912, xiv, 303. 

 & Jour. Exp. Med., 1914, xx, 249. 



6 Howard and Clark, Jour. Exp. Med., 1912, xvi, 850. Sawyer and Herms, Jour. Am. 

 Med. Assn., 1913, Ixi, 461. Clark, Fraser, and Amoss, Jour. Exp. Med., 1914, xix, 223 



7 Jour. Exp. Med., 1914, xix, 411. 8 Loc. cit. 

 Jour. Am. Med. Assn., 1913, Ix, 362; Jour. Exp. Med., 1913, xviii, 461. 



1 Jour. Exp. Med., 1911, xiv, 99; 1912, xv, 90; xvi, 199, 211. 



