The Potential of Systemic Control of Sand Flies Using Fipronil in the Novel Leishmania major (Kinetoplastida: Trypanosomatidae) Reservoirs Meriones tristrami (Rodentia: Muridea) and Meriones crassus (Rodentia: Muridea)

Leishmania major (Yakimoff & Schokhor, 1914), an important causative agent of Old World Cutaneous Leishmaniasis (CL), is transmitted by sand flies among a limited number of gerbilline reservoir-species. We can take advantage of this strong dependency to break the pathogen transmission cycle by using systemic insecticides that render the host toxic to the blood-feeding vector. We evaluated the potential of this approach with two novel reservoir species, incriminated for CL expansion in several sites in the Middle East. Specifically, we evaluated: 1) the residuality of the systemic insecticide fipronil in Meriones tristrami (Thomas, 1892) fed on fipronil-treated baits and 2) the treatments' adulticide effect on sand flies that blood fed on treated and untreated M. tristrami and M. crassus (Sundevall, 1842). We fed M. tristrami with food pellets containing 0.1 g/kg fipronil and used gas chromatograph­mass spectrometery analysis and bioassays to examine its residual toxicity to blood-feeding female sand flies. In M. tristrami, fipronil was rapidly metabolized to fipronil sulfone, found in the blood, urine, and feces for ≥31 d after fipronil admission. The survival of sand flies that blood fed on fipronil-treated M. tristrami and M. crassus was significantly reduced for at least 15 and 9 d respectively, after fipronil admission. These results hold promise for the potential contribution of systemic control approaches to CL integrated management strategies against novel CL (due to L. major) outbreaks in Israel and elsewhere.

Spatial-Temporal Analysis of Lutzomyia trapidoi and Lutzomyia reburra (Diptera: Phlebotominae), in Rural Tourist Locations, Biosphere Reserve and Leishmaniasis Endemic Area, Ecuador.

This research represents the first attempt to assess the spatial and temporal distribution based on micro-meso scales on two species with different host preference habits (anthropophilic vs zoophilic), in the major Leishmaniasis endemic area in Ecuador, tourist locations, and Biosphere reserve. Phlebotomine species, Lutzomyia trapidoi (Fairchild) and Lutzomyia reburra (Fairchild and Hertig), were analyzed by trap/habitat/month/locality/altitude, through the Poisson generalized regression model. Our data reveal a bimodal pattern for both species related with low precipitations and preference for forest habitat. Altitude, proximity to the forest, and the river were the variables that determine the hypervolume of the spatial distribution of relative abundance, where the overlap of these two species increases the risk of translocation and circulation of the etiological agent of leishmaniasis in sylvatic environments to rural-tourist-biosphere reserve areas and vice versa. The ecological characteristics of these two phlebotomines could explain the permanence of the major active and endemic focus of cutaneous leishmaniasis in the North-Western Ecuador a key aspect in tourism health-security in alternative tourism.