Where do these bugs come from? Phenotypic structure of Triatoma infestans populations after control interventions in the Argentine Chaco

摘要: House re-invasion by native triatomines after insecticide-based control campaigns represents a major threat for Chagas disease vector control. We conducted longitudinal intervention study in rural section (Area III, 407 houses) of Pampa del Indio, northeastern Argentina, and used wing geometric morphometry to compare pre-spray post-spray (re-infestant bugs) Triatoma infestans populations. The community-wide spraying with pyrethroids reduced the prevalence house infestation T. from 31.9% < 1% during four-year follow-up, unlike our previous studies neighbouring Area I. Two groups bug collection sites differing shape variables before interventions (including 221 adults 11 domiciles) were as reference assigning 44 adults. Wing post-spray, high-density colonies significantly different, suggesting that re-infestant insects had an external origin. Insects one differed strongly all other specimens. A further comparison between both areas supported existence independent re-infestation processes within same district. These results point local heterogeneities dynamics emphasise need expand geographic coverage surveillance operations affected region.