Lukaw, Y.S., Abdelrahman, M.M., Mohammed, Y.O., Ochi, E.B., Elrayah I.E. and Yousif R. Sulaiman.
Abstract
Tsetse flies and Human African Trypanosomiasis (HAT) pose a threat to human health in Kajo-keji County South Sudan. A 6-month study was conducted to assess the performance of molecular and microscopy diagnostic tests to detect trypanosome parasites in tsetse flies, Glossina fuscipes fuscipes. Tsetse field surveys were carried out during the wet season. 750 wild tsetse flies dissected and midguts were tested microscopically. Genomic DNA of Trypanosoma species was extracted from the guts. Four molecular PCR-and LAMP-based tests were performed. Microcopy method revealed infection rate of 12.0% while the molecular diagnostic tests revealed sensitivity of 15%, 40%, 37.5% and 5% using TBR-PCR, ITS-PCR, RIME-LAMP and Pan Tryp LAMP, respectively. The specificity of TBR-PCR, ITS-PCR, RIME-LAMP and Pan Tryp LAMP tests revealed 100%, 34%, 35% and 31%, respectively. These 4 molecular tests have revealed highly significant (P<0.001) diagnostic results. ITS-PCR (40%) and TBR-PCR (100%) were the most sensitive and specific tests. The PCR and LAMP based assays are yet imperative for rapid and accurate detection of Trypanosma brucei gambiense in wild tsetse midguts. Molecular approach is robust and promising and could substantiate microscopy methods in remote rural inaccessible tsetse infested areas. Strategic area wide integrated vector control is needed for the control of HAT in the endemic foci of Kajokeji County South Sudan.
Keywords: Assessment, Diagnostics, trypanosomes, tsetse flies, South Sudan