Evaluation of the efficacy of flumethrin for tsetse control in Lutendele, Democratic Republic of Congo

Abstract

In the Democratic Republic of Congo animal and human Afri­can trypanosomoses are rife over very large areas. Pigs are the major feeding hosts of Glossina fuscipes quanzensis, the sole tsetse fly species present in suburban Kinshasa. In the context of integrated disease control, pig breeding could be used to advantage in tsetse control by applying insecticides on these animals. The aim of this study was to test this hypothesis by comparing the efficacy of flumethrin 1% as a pour-on formu­lation on pigs with the use of flumethrin-treated screens to control G. f. quanzensis and animal trypanosomosis in Luten­dele, suburban Kinshasa. After two years of applications, ento­mological surveys showed that the pour-on treatment of pigs reduced more the apparent density of tsetse flies than the flu­methrin-treated screens although the difference was not signif­icant. Throughout the study no parasite could be detected in the pigs by the parasitological method nor by molecular biol­ogy, but overall 28% of the pigs had positive serology (95% confidence interval [CI]: 21-33). Compared to treated screens, the treatment of pigs with flumethrin was identified as a signif­icant protective factor against seropositivity with an odds ratio equal to 0.28 (95% CI: 0.12-0.57). This study reveals that both control methods significantly reduced tsetse apparent densi­ties, but that the pour-on treatment of pigs seems to be more efficacious than the use of treated screens to protect them against trypanosomosis.