Infestation of rural houses by Triatoma infestans in the region of Los Llanos (La Rioja, Argentina)

Dispersal of Triatoma infestans and other Triatominae species in the arid Chaco of Argentina: Flying, walking or passive carriage? The importance of walking females

“…For the current study, the Independencia department of province La Rioja (Argentina) was selected because it has the highest infestation rates within houses (45.1%) and in peridomestic structures (57.3%), according to a previous assessment by the Programa Chagas La Rioja (ChLaR) in April 2006, before their intervention efforts (Porcasi et al 2007). Our aim in the present study was to analyse the active dispersal of T. infestans (flying and walking) and the possible role of chickens as passive carriers of the insect in peridomestic areas of La Rioja.…”

New structures for goat corrals to control peridomestic populations of Triatoma infestans (Hemiptera: Reduviidae) in the Gran Chaco of Argentina

“…This has been reported for La Rioja (Soler et al 1977) and Córdoba (Ronderos et al 1980) and has later been confirmed by a number of studies (e.g., Cecere et al 1997). Pyrethroid formulations applied to these structures as suspension concentrates have low efficacy for removing T. infestans and, as a consequence, commonly leave residual populations that recover their numbers after one or two years (Gorla 1992, Gürtler et al 1994, 2004, Cecere et al 1997, Porcasi et al 2007.…”

“…In Independencia, the controls were not replaced by new corrals at the end of the study. A preliminary assessment of the infestation of houses conducted by the PChLR in April 2006 found that 57.3% of the peridomestic structures were infested by T. infestans (Porcasi et al 2007). During the assessment, teams of two people searched the ecotopes in the peridomestic structures for at least 15 min using an aqueous solution of tetramethrin (0.2%) as a dislodging agent.…”

Response of Triatoma infestans to pour-on cypermethrin applied to chickens under laboratory conditions

“…Vector control programmes using the traditional pyrethroid spraying of intra and peridomestic structures of rural houses are not as successful as programmes outside the Chaco Region. Traditional spraying is highly effective inside domiciles, but it frequently leaves a number of residual peridomestic vector populations, as reported in the southern part of the Chaco Region by Porcasi et al (2006Porcasi et al ( , 2007. These residual populations eventually recolonise the domestic rooms and re-establish the domestic transmission cycle of Trypanosoma cruzi, as shown by Gurtler et al (2007) in the central area of the Argentinean Chaco.…”