Deltamethrin 10%-Impregnated Screens Pitched in a Tsetse Endemic Area in the Sudano-Sahelian Region of Cameroon Reduce Tsetse Fly Density and Trypanosomosis Incidence

Abstract

A field trial was conducted in order to evaluate the efficacy of Deltamethrin-impregnated screens in a tsetse endemic zone in Cameroon over a period of 26 months (September 2011 to October 2013). Tsetse barriers consisted of Deltamethrin-treated odor-baited targets (n = 376), deployed on Bini pasture. Similarly, biconical traps were also installed (100 - 200 m apart in each site) for 48 h during sampling (the beginning and the end of the dry and the rainy seasons), and screen density was 1 screen per 100 m2. Parasitological and hematological analyses were carried out using standard protocols, namely, the Buffy Coat Examination (BCE) and hematocrit evaluation. Trypanosomes identified included: Trypanosoma congolense, T. vivax, and T. brucei brucei. Overall fly catch was 1491 flies (Glossina m. submorsitans and G. tachinoides). The overall mean apparent density of flies before deployment of traps was 28.9 flies/trap/day (F/T/D)±12.48 SD, which was significantly higher (P > 0.05) than the density post screen installation of 18.4 F/T/D ± 5.67SD. BCE positive samples, and PCV did not show a statistically significant difference (P > 0.05) with season. Disease incidence was not significantly different (P > 0.05) before or after the deployment of screens. Body weight was significantly different (P 0.05) pre or post-intervention with screens. Body weight was significantly different (P 0.05). In conclusion, screens readily cleared tsetse infestation and reduced trypanosomosis incidence, as well as improved host health and reduced related risk factors in the area.

Keywords

• Deltamethrin-impregnated screens
• cattle
• tsetse control
• trypanosomosis
• Cameroon