Oral treatment of rodents with insecticides for control of sand flies (Diptera: Psychodidae) and the fluorescent tracer technique (FTT) as a tool to evaluate potential sand fly control methods

Abstract

In laboratory studies, insecticides (diflubenzuron, novaluron, methoprene and, pyriproxyfen) that have been incorporated into rodent diets were effective as feed-throughs against sand fly larvae. Novaluron also was effective against sand fly larvae at low concentrations and under simulated field conditions. Ivermectin has been shown to be effective as a systemic insecticide, killing 100% of blood-feeding sand flies for up to seven d after rodents were treated. The fluorescent tracer technique (FTT) is the use of certain fluorescent dyes (rhodamine B or uranine O) as feed-through transtadial biomarkers for phlebotomine sand flies, systemic biomarkers for blood-feeding sand flies, and permanent markers for nectar-feeding sand flies. The results of these laboratory studies provide proof of concept for the FTT and indicate that the FTT could be used to delineate specific foci with rodent/sand fly associations that would be susceptible to control by using feed-through or systemic insecticides, or foci where insecticide-treated sugar baits could be used against sand flies. Journal of Vector Ecology 36 (Supplement 1): S132-S137. 2011.

Systemic insecticide treatment of the canine reservoir of Trypanosoma cruzi induces high levels of lethality in Triatoma infestans, a principal vector of Chagas disease

“…The label claim of all three drugs is to combat fleas and ticks, with additional published studies showing varying activities against phlebotomine sandflies (vectors of Leishmania and some viruses) [12, 13]. All candidate products were administered in the recommended dose from the manufacturer (Table 1, Fig.…”

Oroya Fever and Verruga Peruana: Bartonelloses Unique to South America

“…Recently, novel research has focused on sand fly control methods that capitalize on the close ecological interaction between sand flies and rodents. Feed-through or systemic insecticides such as ivermectin or spinosad incorporated into rodent baits have been shown to cause 100% mortality of bloodfeeding sand flies for at least one week [217], [218]. In follow-on studies, it was shown that rodents fed on fipronil produced feces that were toxic to coprophagous larvae for up to 21 days.…”

Laboratory Evaluation of Rubidium as a Long-Lasting Marker for Bloodfeeding Sand Flies (Diptera: Psychodidae)

“…Rhodamine B also can be used in conjunction with insecticide applications targeting rodents for quality control of their insecticidal activity against sand ßies (Mascari et al 2011). In these studies, the collection of bloodfed sand ßies marked with rhodamine B is considered an indication of the failure of an insecticide application.…”

“…The ßuorescent tracer technique is a system through which rodents passively acquire a biomarker through treated bait. In Þeld studies, rhodamine B has been incorporated into rodent baits for feed-through and systemic marking of sand ßies, allowing the determination of adult sand ßies that have fed on the feces of baited rodents as larvae, or that have taken bloodmeals from baited rodents (Mascari et al 2011).…”

“…Rodents serve as the reservoirs for several Leishmania parasites including Leishmania major, Leishmania mexicana, and Leishmania amazonensis (Dedet et al 1989, Disney 1968, Kerr et al 1995, Saliba et al 1994. The concept of breaking the cycle of transmission of L. major recently has been explored through targeting sand ßies that feed on rodent reservoirs by incorporating systemic and feed-through insecticides into rodent baits (Mascari et al 2011). While such a targeted intervention would have an epidemiological impact, it may not noticeably reduce the overall sand ßy population because of females feeding on hosts other than targeted rodents.…”