36 REVIEW — TKOnCAL MEDICINE, ETC. 



Dengue. Cai-pontcr and Sutton'* investigated the patliology of dengue fever in 1904. 

 They failed to find any organisms in the blood of dengue cases, nor were they able to 

 implicate any of the mosquitoes with which they worked. C'nlrx faUgaiis, however, was not 

 one of these. In throat swabs a small diplococcus was found, either free or in the epithelial 

 cells. A leucopainia was found present from the first, and it is suggested that a diplococcus 

 or delicate, bipolar staining bacillus like Pfeiffer's bacillus of influenza may be the cause, 

 infection taking place by way of the respiratory tract. 



A full report of an epidemic in Brisbane in 1905 will be found in the Journal of Tropical 

 Medicine for December 15th, 1905. In some instances the incubation period seemed as short 

 as 24 hours. The characteristic " breakbone " pains were not much in evidence. Avery 

 minute account of the symptoms is given. As rare complications, pneumonia, pleurisy, 

 parotitis and orchitis are mentioned. Ulceration of the oral mucous membrane and the 

 fauces, and gingivitis were noticed. Diarrhoea with mucous evacuations was not uncommon 

 and dysuria occurred. As sequelae, boils and carbuncles, an itchy vesicular eruption of the 

 hands, muscular rheumatism, neuralgias, giddiness, nervous depression and loss of memory 

 are recorded. Eye lesions were fortunately rare. It is pointed out that the initial symptoms 

 of dengue closely resemble those of yellow fever. In the differential diagnosis from influenza, 

 stress is laid on the rash, not, however, a constant symptom, and still more on the almost 

 invariable absence of catarrhal symptoms of the respiratory tract and the extreme rarity of 

 pulmonary complications. The few differential leucocyte counts made did not show the 

 apparently characteristic changes to be detailed immediately. No evidence is adduced as 

 to etiology. 



Stitt- has a paper on the blood changes, and details what he considers the most 

 characteristic blood findings as follows : — 



1. Absence of a demonstrable protozoon. 



2. Leucopaenia. 



3. Diminution of polymorphonuclears. 



4. A striking variation in the percentage of other leucocytes at varying periods of the disease. At first 

 a large increase in the small lymphocytes is observed, then the appearance of a greater proportion of large 

 lymphocytes, and in the final stages (at the time of the terminal rash and during convalescence) a most striking 

 increase in the mononuclears. 



Stitt failed to find the so-called protozoon described by Graham, ^ of Beirut, but certain 

 observations led him to believe that some species of culex is very probably the transmitter of 

 the disease. 



The following are the important conclusions of Ashburn and Craig* as a result of their 

 ■work on a dengue epidemic occurring near Manila in the Philippines : — 



1. No organism, either bacterium or protozoon, can be demonstrated in either fresh or stained specimens 

 of blood with the microscope. 



2. The red-blood count in dengue is normal. 



3. There occur no characteristic morphological changes in the red or white corpuscles in this disease. 



4. Dengue is characterised by a well marked leucopenia, the polymorphonuclears being decreased, as a 

 rule, while there is a marked increase in the small lymphocytes. 



5. No organism of etiological significance occurred in broth or citrated blood cultures. 



6. The intravenous incubation of unfiltered dengue blood into healthy men is followed by a typical 

 attack of dengue. 



7. The intravenous inoculations of filtered dengue blood into healthy men is followed by a typical attack 

 of the disease. 



8. The cause of the disease is, therefore, probably ultra-microscopic iu size. 



» Carpenter, D. N., and Sutton, R. S. (January 21st, 1905). Journal of Amcricda Medical Association. 



■' Stitt, E. R. (June, 1906), "A Study of the Blood in Dengue Fever, with Particular Reference to the 

 DiSerential Count of the Leucocytes in the Diagnosis of the Disease." Philippine Journal of Science, p. 511, Vol. I. 



=> Graham, H. (July 1st, 1903), " ' The Dengue,' a Study of its Pathology and Mode of Propagation." Journal 

 of Tropical Medicine, p. 209, Vol. V. 



•* Ashburn, P. M., and Craig, C. P. (June 15th, 1907), "Experimental Investigations Regarding the Etiology 

 of Dengue Fever." Journal of Infectious Diseases, p. 440, Vol. IV. 



* Article not consulted in the original. 



