162 REVIEW — TROl'ICAL MEDICINE, ETC. 



Plague — Lamb,' a member of the Commission, in replying to certain criticisms by Hossael<, has 



continued some interesting notes. He deals specially with the multiplication of plague bacilli in the 

 flea's stomach, where everything favours their increase. The faices of a tlea are full of 

 plague bacilli, and while it is sucking blood it is constantly squirting out fiBces from the anus. 

 Thus a mass of bacilli are deposited near or on skin abrasions, a condition most favourable 

 for infection. He concludes by saying that the facts proved are («) that bubonic plague in 

 man is entirely dependent on the disease in the rat ; and (6) that infection is conveyed from 

 rat to rat, and from rat to man solely by means of the rat flea. 



Pranc^a'-* has also drawn attention to the skin lesions in plague, making special mention 

 of the carbuncles which may be present, and which differ from those found in anthrax, the 

 oedema not being so pronounced and the surrounding ring of vesicles often absent. 

 Pemphigus, he notes, is rare. 



The Indian Medical Oaietfe for July, 1906, constitutes a special plague number, and it is 

 remarkable liow many divergent views are expressed. Those of Browning Smith appear to 

 be most in line with the findings of the Indian Plague Commission. A few of his conclusions 

 may be quoted : — 



1. The flea can retain the plague bacilhis alive and virulent bom seven to eight days (Ziroglia). 2. Man 

 is, in the large majority of instances, infected through the skin, though the breach of continuity is too small to 

 be detected. 3. The rat flea, when deprived of its host, will attack man and animals other than the rat. 4. The 

 rat flea has been found on pl.ague-stricken man and animals other than the rat. 



In India tlie four fleas commonly associated with man and rats are — 1. The cat flea, 

 P. felis V. serraficfps, small and dark ; (2) The human flea, P. irriians, large and somewhat 

 light-coloured ; (3) The black rat flea of the black rat (Mus rattus), P. cheopis, small, light- 

 coloured ; (4) The brown rat flea of the brown rat (Mus decumanus), Ceratophyllus fasciatufi. 



A few of our Sudanese fleas have been identified, mostly by Eothschild. One knows 

 that P. cheopis is common, and hence Rothschild's^* description may be given : — 



This species is larger than P. nuhicus, the jialpus being shorter than the rostrum and not reaching to the end 

 of the eo.x8e. lu the male, sternites, three to seven inclusive, bear four bristles ; while those of the female have 

 five. The hind femur bears, in addition to the lateral series of hairs, two suljventral bristles before the apex. The 

 first segment of the mid-tarsus less than two-thirds the length of the second, while that of the hind tarsus is 

 about three-quarters as long again as the second segment. The long apical bristles of the .second segment of the 

 hind tarsus reach to the middle of the fifth segment in the ^, and not quite so far in the !J. The fourth 

 segment is as in F. imbicus. The eighth sternite bears two long bristles before the end on each side, and 

 numerous short ones besides. The anterior process of the clasper of the male is compressed, being asymmetrical 

 in shape. The upper, or anterior, edge is convex, bearing along this edge a number of rather long bristles. The 

 second process of the clasper is slender, with a few short hairs at its end. The ninth .sternite gradually widens 

 towards the apex. The plate of the penis is curved upwards and pointed at the end. 



It has been re-named Loemopsylla cheopis (Rothsch). The others, all of the same genus, 

 are : — 



L. pallidiis Taschenb. 



L. cleopatiw Rothsch. 



L. nuhicus Rothsch. 



L. chersinns Rothsch. 



L. nilnticHs Jordan and Rothsch. 



I have never seen P. irritans, nor have I heard of its being reported from the Sudan, 

 though no doubt it occurs in some districts. 



Mention may now be made of Strong's'' vaccine for plague, which consists of living 

 avirulent cultures of B. pestis. He says that a plague culture, which in a dose of two whole 

 agar cultures does not kill a series of guinea pigs, is sufficiently weak to be used for human 

 inoculations, and no plague culture should be so used unless this can be absolutely guai-anteed. 

 He tested the action of this vaccine in Manila, commencing with a dose of 1/100 of a loop 

 and going on to the injection of a whole agar culture. The mortality amongst the inoculated 

 was 16-6 per cent, as against 66-6 per cent, among the uninoculated. 



' Lamb, Q. (May, 1908), " Some Remarks on the Report on Plague, etc." Indian Medical Gazette, Vol. XI.II. 



' Fran9a, C. Quoted in Merlical Annual, for 1907, p. 442. 



" Rothschild, N. C. (1903). Entomologists' Monthly Magazine, Second Series., p. So, Vol. XIV. Quoted in 

 Medical Annua!, 1907. 



* Strong, R. P. (June, 1907), " Studies in Plague Immunity." Philippine Journal of Science, Vol. II., B. Med. 

 Sciences. 



• Article not consulted in the original. 



