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Trypanosomosis is a vector-borne zoonotic disease transmitted by the tsetse fly (Glossina species). The condition is caused by protozoa known as Trypanosomes. In 2009, large-scale aerial spraying with deltamethrin at 0.26-0.3 g/ha, was undertaken in 5000 km2 covering parts of the Sesheke and Shang’ombo districts to control tsetse flies animal trypanosomosis in cattle in the area. Cattle were sampled for prevalence and incidence of trypanosomosis before, during, and, after aerial spraying as a circuitous way of detecting the presence of the primary vector (tsetse flies). Buffy coats, thick and thin dry smears were applied in the parasitological tests. In the baseline survey, 1,866 cattle were presented, and 25.7% (n = 481) were sampled and examined. Trypanosoma spp. was detected in 1.9% (n = 9) of animals. Six sentinel herds (four treatments and two controls) with 20 animals per herd were monitored for the incidence of AAT during and after aerial spraying, and prevalence was compared among the three phases. The results showed that no new case of trypanosomosis was detected in the treatment herd during the aerial spraying and three months into the postaerial spraying period except 0.83% (n = 1) in the control herd [Mid-P exact; p-value = 0.167 (1-tailed)]. This suggests an association between deltamethrin aerial spraying and trypanosomosis. In conclusion, there was a significant reduction in trypanosomosis prevalence following the aerial spraying operation. This indicates that aerial spraying significantly reduced the tsetse population and subsequently reduced disease transmission to cattle in the area. Furthermore, it indicates that aerial spraying was an effective method of controlling trypanosomosis in cattle. There is a need to extend this operation to other tsetse-infested areas in the country.

The capacity to detect, control and manage emerging and re-emerging zoonotic diseases in Africa has been limited by a lack of utilisation of available reporting structures and policies to support programmes at national and local levels. This study explored the impact of the Zambian government policies on animal and human disease reporting and management and on One Health opportunities. An in-depth review and analysis of strengths, weaknesses, opportunities, and threats in the existing policies and reporting structures in the departments responsible for Veterinary Services, Health, and Wildlife, was conducted. According to our findings, sub-optimal implementation of existing policies related to the control of zoonotic diseases was impacting disease reporting, and reporting structures play an important role in effective and sustainable reporting of zoonotic diseases. Further, the study explored capacities and strategies in trypanosomiasis control as a case study that could prompt effective adoption of a One Health approach, and as such, the study suggests measures that could help to assess the performance of a One Health system in the control of African trypanosomiasis and other zoonotic diseases. [ABSTRACT FROM AUTHOR]

Communities living in African animal trypanosomiasis (AAT) endemic areas of Zambia use several control strategies to protect their livestock from the devastating effects of trypanosomiasis. Several studies have reported the effectiveness of trypanosomiasis control strategies based on retrospective data. In this study, we assessed incidence rates of AAT in cattle ( n = 227) using a prospective cohort study comprising 4 treatment groups, i.e., Diminazene aceturate, Isometamidium chloride, Cyfluthrin pour-on and Cypermethrin treated targets. The study was conducted in Mambwe district in Eastern Zambia between February 2019 and March 2020. The endemic prevalence of AAT for each group was determined using ITS-PCR prior to application of treatments. High endemic trypanosome pre-treatment rates were found in all Groups (Diminazene aceturate (61%), Isometamidium chloride (48%), Cyfluthrin pour-on (87%) and Cypermethrin targets (72%)). The overall apparent prevalence for the Mambwe district was 67% (152/227) and true prevalence at 95%CI was 63–71%. Once treatments were implemented, 12 monthly follow-ups were conducted. The average monthly incidence rates without standardization recorded: Diminazene aceturate (67%) Isometamidium chloride (35%), Cyfluthrin pour-on (55%) and Cypermethrin targets (61%). Incidence rates were standardized considering the endemic level of disease for each Group and the average standardized monthly incidence rate in the Diminazene aceturate Group was 7%; the Isometamidium chloride Group −13%; the Cyfluthrin Group −26%; and the Cypermethrin target Group, −17%. All Groups showed a decrease in incidence of AAT over the period of the study with the Cyfluthrin group showing to be the most effective in reducing AAT incidence in cattle.

The effect of human-associated habitat degradation on tsetse populations is well established. However, more insights are needed into how gradual human encroachment into tsetse fly belts affect tsetse populations. This study investigated how wing vein length, wing fray categories, and hunger stages, taken as indicators of body size, age, and levels of access to hosts, respectively, in Glossina morsitans morsitans Westwood (Diptera: Glossinidae) and Glossina pallidipes Austen (Diptera: Glossinidae), varied along a transect from the edge into inner parts of the tsetse belt, in sites that had human settlement either concentrated at the edge of belt or evenly distributed along transect line, in north-eastern Zambia. Black-screen fly round and Epsilon traps were used in a cross-sectional survey on tsetse flies at three sites, following a transect line marked by a road running from the edge into the inner parts of the tsetse belt, per site. Two sites had human settlement concentrated at or close to the edge of the tsetse belt, whereas the third had human settlement evenly distributed along the transect line. Where settlements were concentrated at the edge of tsetse belt, increase in distance from the settlements was associated with increase in wing vein length and a reduction in the proportion of older, and hungry, tsetse flies. Increase in distance from human settlements was associated with improved tsetse well-being, likely due to increase in habitat quality due to decrease in effects of human activities., (© The Author(s) 2020. Published by Oxford University Press on behalf of Entomological Society of America.)