Parasites & Vectors

official impact factor 2.13

Open Access Research

Experimental evaluation of insecticidal paints against Triatoma infestans (Hemiptera: Reduviidae), under natural climatic conditions

Ivana Amelotti, Silvia S Catalá and David E Gorla*

Author Affiliations

Centro Regional de Investigaciones Científicas y Transferencia Tecnológica de La Rioja (CRILAR). Entre Ríos y Mendoza s/n (5301) Anillaco, La Rioja (Argentina)

For all author emails, please log on.

Parasites & Vectors 2009, 2:30 doi:10.1186/1756-3305-2-30

Published: 8 July 2009

Abstract

Background

Triatoma infestans is the main vector of Chagas disease in the Gran Chaco region of South America. The traditional spraying technique used for the application of pyrethroid insecticides has shown low efficiency in the elimination of the vector species populations occupying peridomestic structures of rural houses in the endemic area of Argentina. As part of studies looking for better alternatives, we evaluated the residual effect of insecticidal paints on the mortality of fourth instar nymphs of T. infestans.

Results

The study was based on an experimental design that included two groups treated with an organophosphate (Inesfly 5A IGR™) and a pyrethroid (Inesfly 5A IGR NG™) formulations of the paint, that were applied on wood, cement blocks and adobe bricks under natural climatic conditions. A third group was an untreated control. Both paint formulations showed very long residual activity, producing mortality of 84% and 98% (pyrethroid and organophosphate formulations, respectively) after 12 months of the paint application. After eight months, nymphs exposed during 6 hours to the painted surfaces with the pyrethroid and organophosphate formulations showed 81.33% and 100% mortality, respectively.

Conclusion

The organophosphate- and pyrethroid-based insecticidal paints showed a very long residual activity on the mortality of fourth instar nymphs of T infestans, compared with the traditional spraying technique used for the application of pyrethroid insecticides in peridomestic structures of rural houses in the endemic region for Chagas disease in the Gran Chaco of Argentina. The application of the paints by trained personnel of the vector control programmes could be considered as an alternative control tool in areas where the traditional methods have failed or showed low efficacy.