Development of a cheap, efficient synthetic host odor blend to attract and capture triatomines, vectors of chagas disease

GARCIA MAILEN; IBARRA BOUZADA, LUCIA; PERUSSET, SA; CECERE C; N BURRONI; GUERENSTEIN P.G.

Congreso; 5th Meeting of the Latin American Association for Chemical Ecology,; 2018

Chagas disease remains as an important vector-borne neglected disease. In the absence of an effective treatment for chronic human infection or vaccines, the prevention of vector-borne transmission of Chagas disease relies on suppressing house infestations by triatomine bugs. Vector control is mainly accomplished by insecticide spraying. However, this is not ideal considering that insects can develop resistance to insecticides, and that these chemicals could affect people. The use of lured trap devices appears to be a sustainable and an environmentally-friendly method for vector monitoring and control. Our aim is to develop attractive odor lures to be used in field traps. It has already beenshown that a synthetic, CO2-free, host odor blend can efficiently attract and capture triatomines. This blend consists of L(+)-lactic acid, pentanoic acid and ammonia (the basic blend). The aim of this study was 1) to develop an efficient blend as cheap as possible and2) to increase the attraction efficiency of the blend. Tests were carried out using T. infestans nymphs in a dual-choice trap olfactometer. Odors were delivered from LDPS (Low density polyethylene sheets) bags. To assess this 1) we replaced lactic acid (2-Hydroxypropanoic acid) with the cheaper pyruvic acid (2-Oxopropanoic acid, a host odor detected by triatomines) and 2) we added a 4th component to the basic blend: 3-methyl 1-butanol (another host odor). Results showed low attraction and captureefficiency of the blend with pyruvic acid, even when this compound was tested at 3 different doses. The negative control showed 9% capture, the positive control (mouse) showed 72%, while blends with pyruvic acid reached 30% capture at most. Thus, in the context of our tests, blends with pyruvic acid are not efficient at attracting and capturing triatomines. Similarly, in the other series of experiments, mixtures with 3-methyl 1- butanol were not efficient at attracting and capturing triatomines. Results of these tests will be discussed.Funding: ANPCyT (PICT 2015 N3260) and CONICET (PIP 2015-2017), Argentina.