DISPERSAL OF PHLEBOTOMUS-PAPATASI (SCOPOLI) AND PHLEBOTOMUS-LANGERONIA NITZULESCU IN EL-HAMMAM, MATROUH GOVERNORATE, EGYPT

The dispersal of Phlebotomus papatasi (Scopoli) and P. langeroni Nitzulescu was studied using the mark-release-recapture techniques in the summer of 1987, at El Hammam, Matrouh governorate. In one experiment, 739 specimens (472 P. papatasi and 267 P. langeroni) were marked with fluorescent powders and released in 5 batches at one point. In a 2nd experiment, 1,524 specimens (571 P. papatasi and 953 P. langeroni) were marked and released in 6 batches at the same point. In the 1st exp., 116 (15.7 %) marked sand-flies were recaptured 1-9 nights after release. In the 2nd exp., 218 (14.3 %) marked sand-flies were recaptured 1-13 nights after release. All recaptured flies were examined by UV lamp. Male sand-flies stayed near the release point and were not captured at distances > 600 m in the 1st exp., but in the 2nd exp., they travelled a longer distance > 1,400 m. This was also true for blood fed females which generally remained within 400 m for the first three nights then dispersed to distance of 600 m in the 1st exp. and > 1,400 m in the 2nd exp. Unfed females quickly moved away from the relase point, sometimes to distances of 900 m or more in the 1st exp. and 1,500 m in the 2nd exp. Sandfly movement was affected by wind velocity, wind direction and presence of hosts. The dispersal of Phlebotomus sandflies confirms that leishmaniasis can be dispersed readily by the movement of the vector.