Community-based surveillance and control of Chagas disease vectors in remote rural areas of the Gran Chaco: a five-year follow-up.

CECERE MC; RODRIGUEZ-PLANES LI; VAZQUEZ PROKOPEC GM; KITRON U; GÜRTLER RE

ACTA TROPICA

ELSEVIER SCIENCE BV

Lugar: Amsterdam; Año: 2019 vol. 191 p. 108 - 115

0001-706X

Prevention of Chagas disease vector-borne transmission mostly relies on the residual application of pyrethroidinsecticide. Persistent or recurrent house infestation after insecticide spraying remains a serious challenge inremote, resource-poor rural areas where public health services face substantial constraints. Here we use generalizedestimating equations and multimodel inference to model the fine-scale, time-lagged effects of a community-based vector surveillance-and-response strategy on house infestation and abundance of Triatoma infestansin four rural communities of the Argentine Chaco over a five-year period. Householders and communityleaders were trained to detect triatomines and spray with insecticides their premises if infested. House infestationand vector abundance were consistently higher in peridomestic habitats than in human habitations(domiciles). Householders supplemented with sensor boxes detected infested domiciles (67%) more frequentlythan timed-manual searches (49%). Of all houses ever found to be infested by timed-manual searches, 76% weresprayed within six months upon detection. Domestic triatomine abundance was significantly related to houselevelinsecticide spraying during the previous year (inversely) and current peridomestic abundance (positively).Peridomestic triatomine abundance significantly increased with current domestic bug abundance and maximumperidomestic abundance during the previous year, and was unaffected by insecticide spraying. Our study providesnew empirical evidence of the interconnection and flow between domestic and peridomestic populations ofT. infestans under recurrent insecticide treatments, and supports targeting both habitats with appropriate tacticsfor longer-lasting, improved vector control. Community-directed efforts succeeded in controlling domestic infestationsand interrupting domestic transmission, whereas persistent peridomestic infestations demand sustainedcontrol efforts to address domestic reinvasions.