Insecticide Resistance in Triatomines

MOUGABURE CUETO GASTON; PICOLLO MARÌA

Triatominae - The Biology of Chagas Disease Vectors

Springer

Año: 2021; p. 537 - 555

                                   The control of Chagas disease vectors has been based principally onspraying dwellings with insecticides. This strategy reduced the geographic rangeand infestation prevalence of major vectors leading to the interruption of diseasetransmission in several areas from endemic regions. However, triatomine survivalafter spraying pyrethroid insecticides, mainly in the case of Triatoma infestans(Hemiptera: Reduviidae), has become more frequent in the last two decades.Insecticide resistance emerges as one main explanation for these chemical controlfailures. This chapter reviews the evolution of insecticide resistance in triatomines.Resistance to pyrethroids was first detected in T. infestans in the 1990s. But, it wasonly in the 2000s that resistance associated with control failures was described forthe latter species in Argentina and Bolivia. Different resistant profiles were demonstratedfor T. infestans suggesting that resistant foci originated independently. Themain resistance mechanisms (i.e., enhanced detoxification, target-site modifications,and reduced penetration) were described for this species. Resistance to deltamethrinin T. infestans was shown to be controlled by an autosomal and incompletelydominant character. The resistance evolving in T. infestans from the Chaco ecoregionwould be associated with different pleiotropic effects of the genes that conferresistance. Moreover, environmental variables linked to temperature and precipitationwould explain part of the distribution of resistant populations of T. infestans insome endemic areas of the Chaco ecoregion. Finally, the possible resistance managementstrategies for triatomines are discussed.