HISTORICAL REVIEW 119 



Nicolle, Blanc, and Conseil (1914) found cocco-bacilli like 

 those described by Sergent, Foley, and Vialette (1914) in lice 

 collected from a typhus free region (Tunis). 



The first work of importance concerning the association of 

 rickettsia and typhus was that of da Rocha-Lima published 

 in two papers in 1916. 



In the first paper (1916 1 ), da Rocha-Lima mentions obser- 

 vations made with von Prowazek before his death in which 

 rickettsia were found in great numbers in lice from typhus 

 patients. It was during this work that von Prowazek and da 

 Rocha-Lima became infected with typhus and von Prowazek 

 died. 



Da Rocha-Lima continued the work and established the 

 frequent presence of the organisms in question in lice from 

 typhus patients. He insisted that Giemsa's stain was neces- 

 sary for their demonstration, since the ordinary stains used for 

 bacteria stained them unsatisfactorily if at all. He described 

 them as organisms with contours less sharply defined than 

 those of bacteria and consisting of two substances, one stain- 

 ing faintly and the other, usually at the poles, taking a deep 

 stain. The heavily stained polar portions are joined by the 

 lightly staining outer substance. In the dark field these bodies 

 looked to him like paired granules; in water they disintegrated. 

 Measurements given by da Rocha-Lima were 0.3/i by 0.4/x for 

 single granules, 0.3/z by 0.9/-1 for double granules or rods. 



Da Rocha-Lima was the first to study these organisms in 

 sections of lice and found them in seventeen or eighteen lice 

 sectioned while none were found in a hundred normal lice. 

 He discovered that these bodies multiplied within the epithelial 

 cells of the louse's stomach and observed the changes produced 

 in the cells by the growth of the organisms, distension and 

 finally rupture. 



In smear preparations he found similar bodies in three lice 

 from non-typhus sources, a fact which he did not attempt to 

 explain. 



Later in the same year (1916 2 ) da Rocha-Lima, in honor of 

 Ricketts and Prowazek, gave the name Rickettsia prowazeki 



