46 PAPPATACI FEVER [CH. 



The eyes are injected, especially across the middle of the 

 conjunctivae, and the bulbi are painful on pressure. The distur- 

 bances of the digestive system are very inconstant ; vomiting 

 occurs in about one-third of the cases, usually as an initial 

 sjrmptom. Constipation is the rule when the temperature is 

 high, but later on, diarrhoea often sets in and the liquid stools 

 may contain blood. Epistaxis is a common phenomenon. 



Various cutaneous eruptions may occur, in the nature of 

 erythema of a morbilliform or multiform character, and a few 

 roseolae. 



The examination of the blood reveals no changes in the 

 number or morphology of the red corpuscles. A pronounced 

 leucopenia has been observed on the first day, and the numbers 

 of leucocytes may fall as low as 1400 per c.mm. on the second 

 day, after which the numbers slowly increase from the third 

 day onwards. 



The percentage of polymorphonuclears varies between 80 

 and less than 50, and Gabbi finds a slight increase of the mono- 

 nuclears. Eosinophile leucocytes are very scarce, their number 

 being below the normal. 



The prognosis is invariably good and the patient's recovery 

 is usually complete within two or three weeks after the begin- 

 ning of the disease. 



In the absence of any knowledge of the causative agent of 

 this disease, the diagnosis can only be based on clinical observa- 

 tions and it is extremely difficult to distinguish between Pap- 

 pataci Fever and various other febrile diseases. The presence 

 of the transmitting agent may be of some help in establishing 

 the diagnosis, but the discovery of the specific microbe is neces- 

 sary before this disease can be distinguished with any certainty. 



Mode of infection. Pappataci Fever is transmitted by the 

 agency of Phlebotomus papatasii, the sand-fly. Possibly P. per- 

 niciosus, minutus, and other species of the genus are also capable 

 of spreading the disease, but up to the present, with the possible 

 exception of Aden^, no cases have been recorded from localities 

 in which P. papatasii is not known to occur. 



^ Sand-Fly Fever is said to occur in this region. The only species of 

 Phlebotomus hitherto recorded from Aden is P. minutus. 



