Abstract:
A trial to control G. m. morsitans with the use of 980 odour-baited, insecticide-impregnated targets was conducted in a 300 km² area in the Eastern Province of Zambia between 1989 and 1991. The area is highly cultivated and cattle density is high (about 8 cattle/km²). Targets were deployed along roads and tracks. Deployment was restricted to suitable tsetse habitat. The effect of the targets on the tsetse population and on the transmission of tsetse-transmitted trypanosomosis was monitored by means of man-walked fly rounds and sentinel herds, respectively. The apparent density of tsetse in the trial area and in adjacent areas, declined rapidly after targets had been deployed. Trypanosomosis incidence in the trial area decreased significantly but did not completely disappear. Results from the trial show that odour-baited targets are effective in controlling Glossina m. morsitans in highly cultivated areas even when deployment is restricted to suitable tsetse habitat. It is concluded that tsetse control operations should be chosen such that either the invasion pressure is low from adjacent areas, or the size of the area is big enough, so that a central challenge-free area can be created.
