Comparison of insecticidal paint and deltamethrin against Triatoma infestans (Hemiptera: Reduviidae) feeding and mortality in simulated natural conditions

摘要

The Chagas disease vector Triatoma infestans is largely controlled by the household application of pyrethroid insecticides. Because effective, large-scale insecticide application is costly and necessitates numerous trained personnel, alternative control techniques are badly needed. We compared the residual effect of organophosphate-based insecticidal paint (Inesfly 5A IGR™ (I5A)) to standard deltamethrin, and a negative control, against T. infestans in a simulated natural environment. We evaluated mortality, knockdown, and ability to take a blood meal among fifth instar nymphs. I5A paint caused significantly greater mortality at time points up to 9 months compared to deltamethrin (Fisher's Exact Test, p < 0.01 in all instances). A year following application mortality among nymphs in the I5A was similar to those in the deltamethrin (χ² = 0.76, df=1, p < 0.76). At months 0 and 1 after application, fewer nymphs exposed to deltamethrin took a blood meal compared to insects exposed to paint (Fisher's Exact Tests, p < 0.01 and p < 0.01 respectively). Insecticidal paint may provide an easily-applied means of protection against Chagas disease vectors.