Prevalence of trypanosomes and selected symbionts in tsetse species of eastern Zambia.

Insect symbionts have attracted attention for their potential use as anti-parasitic gene products in arthropod disease vectors. While tsetse species of the Luangwa valley have been extensively studied, less is known about the prevalence of symbionts and their interactions with the trypanosome parasite. Polymerase chain reaction was used to investigate the presence of and bacteria, in tsetse flies infected with trypanosomes ( and ). Out of 278 captured tsetse flies in eastern Zambia, 95.3% ( = 265, 95% CI = 92.8–97.8) carried endosymbionts: (79.1%, 95% CI 73.9–83.8) and (86.3%, 95% CI 81.7–90.1). Overall, trypanosome prevalence was 25.5% ( = 71, 95% CI = 20.4–30.7), 10.8% ( = 30, 95% CI 7.1–14.4) for 1.4% ( = 4, 95% CI = 0.4–3.6) for both and , and 0.7% ( = 2, 95% CI 0.1–2.6) for Out of 240 tsetse flies that were infected with trypanosome infection was reported in 40 tsetse flies (16.7%, 95% CI = 12.0–21.4) while 37 (16.8%, 95% CI 11.9–21.8) of the 220 infected tsetse flies were infected with trypanosomes. There was 1.3 times likelihood of infection to be present when was present and 1.7 likelihood of infection when was present. Overall findings suggest absence of correlation between the presence of tsetse endosymbionts and tsetse with trypanosome infection. Lastly, the presence of pathogenic trypanosomes in tsetse species examined provided insights into the risk communities face, and the importance of African trypanosomiasis in the area.