The Baseline Susceptibility Levels of Laboratory-Reared Tanzania Fleas to Malathion

  • B. S. Kilonzo
Research Article


Laboratory-reared Xenopsylla brasiliensis and X. cheopis obtained from several parts of Tanzania were tested with 0.5% malathion, using the standard WHO test kit.

Two strains of Xenopsylla brasiliensis (Mbulu and Amani) were more susceptible as 100% mortality was obtained after 12 hr exposure. With the remaining populations, 100% mortality was obtained after 24 hr exposure. LT50 of X. brasiliensis were 3.1, 3.3 and 4.5 hr for Mbulu, Tawalani and Amani strains respectively. Similarly, LT50 of X. cheopis were 8.1, 7 and 5.4 hr for Chunya, Amani and Tawalani strains respectively.

It was generally concluded that malathion was a suitable insecticide for use in flea and consequently plague control in Tanzania as X. brasiliensis and X. cheopis are the commonest flea vectors of the disease in the country. Moreover, the insecticide is locally available and it has limited toxicity on non-target organisms and little persistence in the environment.

Key Words

Fleas malathion plague control rodents 


Des pucés appartenant aux especes Xenophylla brasiliensis et X. cheopis élevées en laboratoire á partir de prélevements opérés dans diffentes régions de Tanzanie ont été soumises á des tests de sensibilité au malathion á une concentration de 0.5% á laide dún test standard repondant aux normes de l’OMS.

Deux souches de X. brasiliensis (Mbulu et Amani) se sont révelées les plus sensibles, montrant une mortalité de 100% apres 12 hr d’exposition á lágent chimigne. Pour les antres souches les 100% de mortalité ont été atteintes apres 24 hr d’exposition.

Le malathioń sést done avec etre un insecticide efficase contre les puces et done bien adapte á la lutte contre la peste en Tanzanie, X. brasiliensis et X. cheopis etánt les plus importants vecteurs de catte maladie dans ce pays. Le malathion a en outre l’avantage d’entre disponible sur le marché local, d’avoir une faible toxicité envers les animaux a sang chand et d’avoir une remanence limite.


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Copyright information

© ICIPE 1986

Authors and Affiliations

  • B. S. Kilonzo
    • 1
  1. 1.Department of Veterinary Microbiology and Parasitology, Faculty of Veterinary MedicineSokoine University of AgricultureMorogoroTanzania

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