59 



NicoLLE (C.) & Blanc (G.). Etudes sur la fievre r§currente poursuivles 

 k rinstitut Pasteur de Tunis : Deuxi^me m6moire (1914). [Studies 

 on recurrent fever carried out at the Pasteur Institute, Tunis : 

 Second memoir (1914).] — Arch. hist. Pasteur, Tunis, ix, no. 2, 

 1st December 1914, pp. 69-83. 



After detailing the result of their researches [see this Review, Ser. B, 

 ii, p. 132], and giving a resume of those of Sergent and Foley [see 

 this Review, Ser. B, ii, p. 200], the authors point out that the exact 

 agreement of the results of independent observers, gives them a 

 special value. They sum up their own work as follows : — (1) As 

 regards the presence in the louse of spirilla visible under the ultra- 

 microscope, these experiments show the continued absence of spirilla 

 from the second to the fifth day, their non-continuous presence from 

 the sixth to the eighth day, and their continued presence from the 

 tenth to the twelfth day. (2) As regards the virulence of lice for the 

 monkey, it was found that it was absent from the second to the fourth 

 day after the infecting meal, that it was present on the fifth and sixth 

 days, and again absent from the eighth to the twelfth day. (3) If the 

 results obtained in 1914, by the examination of lice under the ultra- 

 microscope on the one hand and by using them to infect monkeys on 

 the other, be compared, the following table is obtained : Second, 

 third and fourth days after the infecting meal — no spirilla, no viru- 

 lence ; fifth day — no spirilla, virulence ; sixth day — spirilla present 

 exceptionally, constant virulence ; eighth day — non-continuous 

 presence of spirilla, no virulence ; tenth and twelfth days — constant 

 presence of spirilla, no virulence. Combining their own and Sergent 

 and Foley's results, they arrive at the following conclusions : absence 

 of spirilla and inconstant virulence on the second, third, fourth and 

 fifth days from the infecting meal ; absence of spirilla and constant 

 virulence on the sixth day ; inconstant presence of spirilla and, 

 exceptionally, virulence on the eighth and ninth days. The general 

 conclusion is that the virulence of infected lice has no relation 

 to the presence in these insects of spirilla visible under the micro- 

 scope or ultra-microscope. It is chiefly in its prespirillum phase 

 —i.e., at the moment when it is about to become visible — that the 

 recurrent fever agent shows its highest virulence in the louse. At 

 that moment the louse is most dangerous, but it may be dangerous at 

 any time from that of the infecting meal up to the fifteenth day after 

 the meal. The negative results obtained with monkeys are in no 

 way definitive, as man alone provides an indisputable reaction as 

 regards the virulence of the spirilla. 



NicoLLE (C), Blanc (G.) & Conseil (E.). Nouvelles recherches exp6ri- 

 mentales sur le typhus exanth6matique pratiqu6es 4 I'lnstitut 

 Pasteur de Tunis pendant I'ann^e 1914. [New experimental 

 researches on exanthematous typhus carried out at the Pasteur 

 Institute, Tunis, in 1914.] — Arch. Inst. Pasteur, Tunis, ix, no. 2, 

 1st December 1914, pp. 84-121. 



The authors arrive at the following conclusions : — (1) Lice fed on 



infected monkeys, then crushed and inoculated into the peritoneal 



■cavity of the monkey or guineapig, are virulent for these animals 



