History and Geographical Distribution
History.—While Hirsch gives the credit for the first mention of the disease to the chronicler Gaberti, who described a disease with certain resemblances to dengue as existing in Cairo in 1779, yet, for the reason that certain clinical features of this epidemic would hardly appear to belong to dengue, as we now know it, there would seem to be good ground upon which to give the credit of priority to Benjamin Rush, who, under the designation break-bone fever, gave us a true picture of dengue as it manifested itself in Philadelphia in 1780.
Gaberti was particularly impressed with the knee involvement so that from his description the disease was known as the disease of the knees. He further noted swelling of the fingers and that the pains continued for more than a month. The sudden onset and the sweating would seem to belong to relapsing fever as well as to dengue and in support of the view that the disease described by Gaberti might have been relapsing fever we have the statement of Sandwith that bone pain, chiefly of the knee, is the symptom most complained of by the Egyptian native with relapsing fever.
Boylon, who reported an outbreak of an epidemic disease in Batavia in 1780 stated that everybody was attacked and that the symptoms were almost the same as those ushering in plague—headache, lassitude and pains in the joints. He noted, however, that this epidemic had no bad consequences, patients getting rid of it in three days under moderate diet and copious beverages.
Ashburn and Craig, in 1907, proved that the disease could be transmitted by injections of blood, unfiltered as well as filtered.
Geographical Distribution.—The disease may occur in epidemic form in almost any part of the tropical or subtropical world. It is very common in the countries about the China Sea and in the West Indies.
Etiology and Epidemiology
Etiology.—One can only state that the disease is caused by a filterable virus which is present in the patient’s blood from the second to the fifth day. Graham reported a piroplasm-like organism as the cause but other workers have failed to confirm this. Reports as to bacterial causative organisms have not been verified. Cleland and his colleagues inoculated guinea pigs and rabbits without result and were unable to find spirochaetes. Couvy has reported the presence of short spirochaetes in the blood 2 or 3 hours before the onset of the fever,—never later. They had two or three turns and fine extremities.
Epidemiology.—As regards the epidemiology of dengue there seems to be a general acceptance of the idea that dengue is transmitted by the common culicine mosquito of the tropics, Culex fatigans. There is not, however, that definiteness which attaches to the transmission of yellow fever by Stegomyia calopus or to pappataci fever by Phlebotomus papatasii, in both of which a certain period of development of the unknown filterable virus in the arthropod host is necessary before the insects become capable of transmitting the infections.