Urban infestation by Triatoma infestans in the Argentine Chaco: evaluation of a selective treatment protocol.

GÜRTLER RE; LAIÑO M; CARDINAL MV; ENRIQUEZ GF; GASPE MS; FERNÁNDEZ MP; ALVEDRO A

Congreso; XI Congreso Argentino de Protozoología y Enfermedades Parasitarias; 2017

Triatoma infestans has increasingly been found in urban areas of the Gran Chaco ecoregion where vector-borne transmission of Trypanosoma cruzi still occurs. How to cope with urban infestations in a cost-effective way remains unclear. As part of the longitudinal intervention program ?Avia Terai sin Chagas?, we assessed house infestation with T. infestans in the town of Avia Terai, Chaco, Argentina. The town had last been sprayed with pyrethroid insecticides by the National and Chaco Chagas Programs in 2011-2013 (total, 774 houses). All inhabited (n=1454) houses were visited in February 2016 and manual searches using a flushing-out agent were performed in 412 houses, including those where dwellers reported having seen triatomines, harbored chickens, and in one of every three houses that did not fulfill any of these conditions. T. infestans was found in 56 houses located in 27 of the 125 urban blocks. All infested and adjacent houses were sprayed by local vector control personnel using beta-cypermethrin (Chemotecnica) at 50 mg/m2 in domiciles and a double dose in peridomestic sites. Using a similar survey protocol, the prevalence of house infestation decreased significantly from 13.6 to 2.9% (n=859) in March-April 2017 (Fisher?s exact test, p