diseases of warm climates only; and, clinically, they are characterized by a short incubation period, a short and rapidly developed fever which is usually associated with relatively slow pulse and leucopenia, with relative decrease of the polynuclears. It would be interesting to ascertain if these diseases are mutually protective.
Symptoms.— These are practically the same as those described by McCarrison for the three-days' fever of Chitral, now regarded, as suggested by that observer, as being caused possibly by the sand-fly. After an incubation period of from one to six days, with or without a prodromal stage, the fever is ushered in by slight or more severe rigor. The face becomes flushed, headache is intense, and there is usually severe general aching. In from twenty-four to thirty-six hours the temperature has reached 103-4° F. It keeps about this point for a day longer, and then begins to fall, with or without epistaxis, vomiting, sweating, or diarrhœa, reaching the normal about the end of the third or beginning of the fourth day. The patient continues debilitated, especially mentally, for a week or two longer.
Serious complications do not occur, but in some years diarrhœa, in other years pharyngitis, are features of the epidemic.
There are no important sequelæ. Desquamation is very rare; a point which, together with the absence of an eruption, serves to differentiate this fever from dengue, a disease resembling it in many respects. The mortality is nil in the healthy.
Treatment.— There is no specific known for this disease. Treatment must therefore be conducted on general principles.
As it would appear that three-days' fever is a disease of locality, houses and places believed to be infected should be avoided, and, where possible, disinfected.
With a view to diminishing the local sand- fly pest, all rubbish should be burned or otherwise got rid of, ruinous walls should be demolished, latrines smoked with sulphur fumes and put into sanitary
