Field Evaluation of a New Strategy to ControlLutzomyia longipalpis, Based on Simultaneous Application of an Adulticide–Larvicide Mixture

Abstract

Leishmania infantum (syn. chagasi) is the etiologic agent of visceral leishmaniasis in Argentina, and the phlebotomine fly Lutzomyia longipalpis is its main vector. The objective of this study was to evaluate the effectiveness of Dragon Max, an emulsifiable concentrate formulation containing the pyrethroid permethrin and the larvicide pyriproxyfen, for Lu. longipalpis control under field conditions. The work was conducted in the city of Posadas (Misiones province, Argentina). Comparisons were performed between treated and untreated peridomiciles with poultry, which met previously determined criteria for favoring the presence of Lu. longipalpis. Henhouses and their surrounding area were treated, with the formulation (100 mg of permethrin and 2 mg/m of pyriproxyfen) applied using a hand pump sprayer. Untreated henhouses were used as controls. Phlebotomine abundance was monitored before treatment and then weekly, using Centers for Disease Control and Prevention light traps. Lutzomyia longipalpis was the only phlebotomine species captured. A male/female ratio of 2.5 was observed. The more chickens there were in the henhouses, the greater the number of phlebotomines captured. The treatment resulted in a significant decrease in the number of individuals, which persisted for at least 2 wk. This encouraging result provides a baseline for further studies evaluating the possibility of using Dragon Max as a tool for Lu. longipalpis control.

High effectiveness of an adulticide-larvicide formulation for field control of sandflies (Diptera: Psychodidae) in the city of Clorinda, Argentina

“…The two commercial insecticide formulations used in this study were Dragon Max® and Flop® (Chemotecnica S.A., Argentina). The emulsifiable concentrate (EC) formulation Dragon Max® contains two active ingredients, the pyrethroid permethrin (Juan et al, 2016) and the insect growth regulator (IGR) pyriproxyfen (2%). The emulsifiable concentrate (EC) formulation Flop® contains a single active ingredient, the pyrethroid permethrin (10%).…”

“…longipalpis adults. Consequently, this represents an important risk factor for human health in those households that rear chickens and keep chicken coops in the peridomicile (Salomón et al, 2015; Juan et al, 2016).…”

“…Previous studies have evidenced the effectiveness of permethrin on adult insects of Lu. longipalpis under laboratory conditions (Juan et al, 2014), as well as the effectiveness of the larvicide pyriproxyfen on their immature forms (Juan et al, 2016). Pyriproxyfen is a growth regulator in insects and it's characterized by its selectivity for specific species, with a considerable safety profile towards the environment and non-specific organism, including mammals (Mulla et al, 2003).…”

“…Although there are no previous studies from Argentina on the use of pryriproxyfen specifically for sandflies, its effectivity has been evaluated in other Diptera insects of public health importance (Seccacini et al, 2014; Harburguer et al, 2014; Seccacini et al, 2008). In addition, a new formulation (EC: emulsifiable concentrate) containing the pyrethroid permethrin and the larvicide pyriproxyfen showed promising effectivity in the control of sandflies under field conditions (Juan et al, 2016). However, the comparison of the effectivity of this formulate with the traditional permethrin treatment remains unknown.…”

Establishment of a method for Lutzomyia longipalpis sand fly egg microinjection: The first step towards potential novel control strategies for leishmaniasis

“…A recent study using an adulticide-larvicide mixture of permethrin and pyriproxyfen (Dragon Max ® ) in neighbouring Argentina was effective at significantly reducing the number of Lu. longipalpis 7 . This formulation was effective for at least two weeks but further studies are required to determine if this formulation can have longer-term efficacy.…”