DENGUE FEVER AND CULEX 197 



present day it owes a considerable amount of its im- 

 portance to tlie fact that, together with influenza, it 

 is hable to be confused with yellow fever. Like the 

 latter fever, it appears to follow the trade routes and 

 to burst out without warning into considerable-sized 

 epidemics of an essentially local character. Indeed, in 

 its mode of extension and its tendency to keep to the 

 coast line, it resembles an insect-borne disease, and 

 evidence is accumulating in favour of this view. Thus 

 Dr. H. Graham of Beyrouth has brought forward 

 reasons which show that dengue fever is spread by 

 the Cnleoc fatigans. This observer states that he M^as 

 able to infect (1901) healthy persons by the bite of 

 infected mosquitos, that is, mosquitos which had bitten 

 patients suffering from the disease. 



Dr. Strong of INIanilla likewise (1909) states that 

 recent studies in Manilla point to the Culex fatigans as 

 the transmitting agent, and I have received a note 

 from the Hon. W. Collett, Colonial Secretary, British 

 Honduras, concerning an outbreak of dengue fever in 

 that Colony, in which he states : 



" An epidemic of dengue broke out in the middle 

 of the year 1907, and P.JNI.O. Harrison estimated that 

 45 per cent, of the population suffered. A few who 

 had previously had yellow fever contracted the disease, 

 so that evidently yellow fever does not protect. It was 

 noted that wherever dengue fever occurred the Culex 

 fatigans was also found. Mr. Collett had the culex 

 in his own house, and his youngest child contracted the 

 disease ; both himself and Mrs. Collett, however, 

 escaped, as they had had the disease in Fiji in 1885." 



