30 REVIEW — TROPICAL MEDICINE, ETC. 



Chicken-pox Neech,' Eolleston"* and Porter' have recorded cases in which the eruption became 



—continued confluent, in this and other respects closely resembling that of small-pox. Mackenzie' thinks 

 that varicella, " with its polymorphic eruptions, mature and immature developments and 

 retrogressions, recurrent invasions, uneven temperature and irregular periods of incubation," 

 must be regarded as a mixed infection, and that it is possibly " a non-specific, non-variolous 

 varicella and a very slight but genuine variola infantum of childhood." RoUeston'^ has a 

 paper on the accidental rashes of varicella, which in order of frequency are classed as 

 scarlatiniform, purpuric, morbilliform and mixed. He mentions that there may possibly 

 be a chicken-pox without vesiculation, and discusses the nature of the accidental rashes 

 which are pi'obably septic or toxic. 



Bray" describes a condition amongst the Sudanese. It is called by them Boorglum, and 

 is apt to be mistaken for chicken-pox. It is said to be most common at flood Nile, and takes 

 the form of a superficial rash, papular, vesicular and pustular, affecting the back of the 

 hands and forearms, the dorsum of the feet and the front of the leg. It is probably 

 parasitic, is commonest in those who work with mud bricks, and is best treated by the 

 application of iodine. 



I have seen Boorglum in a Greek bricklayer, and the rash is certainly like that of 

 chicken-pox. There is, however, no constitutional disturbance and the distribution of the 

 eruption is different. 



Chigger. As Sarcopstjlla penetrans is well known in the Bahr-El-Ghazal, and has 

 caused much invaliding amongst men in the Sudanese battalions, the following points in its 

 life-history elicited by Wellman' are likely to prove useful: — 



1. The eggs are .always laid while the chigger is yet embedded in the flesh of her host. Her different 

 behaviour after artificial removal does not form a real exception to these statements. In such an event she 

 extrudes all her eggs at once and dies, but such eggs do not hatch into larvse. Even if the chigger has 

 completed her gestation and has begun to lay her eggs before her removal, only the most mature eggs 

 in the posterior part of the abdomen will develop. 



2. They never (.at least in this climate, Angola) hatch into larvaa in the body of the parent. 



3. They are not laid at one time in masses, but discreetly, and sometimes at considerable intervals, 

 depending on circumstances. If the chiggers are in the sole of the foot, and the infected person walk about, 

 the eggs may be seen dropping from his feet as he goes, or by pressing gently on the skin near a ripe chigger 

 two or three eggs may be seen to escape one after another. Such eggs readily hatch out. So while it is 

 doubtless a good rule to burn all chiggers removed, yet this has no effect on the usual mode of propagation, and so 

 long as natives go about with infected feet the cycle will go on. 



4. The shell of the parent when dead, and empty of eggs, usually dries up in sittt and causes no further 

 trouble. Occasionally it may cause irritation, swellings and ulcers, but most of the abscesses, sores, etc., from 

 chiggers come from removing the insects with septic instruments. 



5. The mature ova, if placed in a glass-covered dish containing some dust from the floor, go through the 

 developmental stages common to all fleas, which have often been described. In natural conditions they develop 

 in the dirt and cracks in the floor, and in chigger countries it is therefore important to compel one's native 

 servants to keep their feet clear of chiggers, and to allow no other natives (especially children, who are always 

 infested) in one's quarters. 



Cholera. The Sudan has always been liable to invasion by cholera from Egypt 

 and from the great pilgrimage centres on the eastern coast of the Eed Sea. Given invasion, 

 the disease is now more likely to be disseminated owing to improved methods of communica- 

 tion and especially to the establishment of the Atbara-Port Sudan Eailway. Hence any 

 acts relating to cholera must ever be of interest to the Medical OfEcer, and more especially 

 when these deal with preventive measures. The useful Indian pamphlet by Duke'" sei-ved 

 as a basis for the cholera notices drawn up this year for Khartoum City and Khartoum 

 North, and to be issued if the disease became epidemic in any part of the country. As these 

 are possibly of some general interest they are here introduced although, happily, their utility 

 or otherwise has not so far had to be tested. 



' Neech, .J. T. (February 24th, 1906), "A Note on a Case of Confluent Varicella." Lancet, p. 515. 



^ Rolleston, J. D. (January, 1906). British Journal of Children's Diseases. 



' Porter, C. R. (May 18th, 1907), " A Case of Confluent Hsemorrh.agic Eruption in Varicella." Lancet, p. 1352. 



■• Mackenzie, J. (January, 1907), " A Study in Varicella." Journal of Royal Institute of Public Health, p. 17. 



' Rolleston, J. D. (M.ay 4th, 1907), " Accidental Rash of Varicella." British Medical Journal, p. 1051. 



° Bray, H. A. (October, 1904). Journal of the Royal Army Medical Corps. London. 



' Wellman, P. C. (December 1st, 1905), "A Point in the Life-History of Sarcopsylla Penetrans." Journal of 

 Tropical Medicine, p. 394. 



" Duke, J., " The Prevention of Cholera, and its Treatment." 3rd Edition. Calcutta, 1905. 



* .iVrticle not consulted in the original. 



