Richard S Gashururu1,2,3, Samuel M Githigia4, Methode N Gasana5, Richard Habimana6, Ndichu Maingi4, Giuliano Cecchi7, Massimo Paone7, Weining Zhao7, Daniel K Masiga8, James Gashumba9. 1. School of Veterinary Medicine, University of Rwanda, P.O. Box 57, Nyagatare, Rwanda. gasirich@yahoo.fr. 2. Faculty of Veterinary Medicine, University of Nairobi, P.O. Box 29053, Nairobi, Kenya. gasirich@yahoo.fr. 3. International Centre of Insect Physiology and Ecology (Icipe), P.O. Box 30772-00100, Nairobi, Kenya. gasirich@yahoo.fr. 4. Faculty of Veterinary Medicine, University of Nairobi, P.O. Box 29053, Nairobi, Kenya. 5. Rwanda Agriculture and Animal Resources Board, PO. Box 5016, Kigali, Rwanda. 6. School of Veterinary Medicine, University of Rwanda, P.O. Box 57, Nyagatare, Rwanda. 7. Food and Agriculture Organization of the United Nations (FAO), Animal Production and Health Division, Rome, Italy. 8. International Centre of Insect Physiology and Ecology (Icipe), P.O. Box 30772-00100, Nairobi, Kenya. 9. Rwanda Polytechnic, P.O. Box 164, Kigali, Rwanda.
Abstract
BACKGROUND: Glossina (tsetse flies) biologically transmit trypanosomes that infect both humans and animals. Knowledge of their distribution patterns is a key element to better understand the transmission dynamics of trypanosomosis. Tsetse distribution in Rwanda has not been well enough documented, and little is known on their current distribution. This study determined the current spatial distribution, abundance, diversity, and seasonal variations of tsetse flies in and around the Akagera National Park. METHODS: A longitudinal stratified sampling following the seasons was used. Biconical traps were deployed in 55 sites for 6 consecutive days of each study month from May 2018 to June 2019 and emptied every 48 h. Flies were identified using FAO keys, and the number of flies per trap day (FTD) was used to determine the apparent density. Pearson chi-square (χ2) and parametrical tests (t-test and ANOVA) were used to determine the variations between the variables. The significance (p < 0.05) at 95% confidence interval was considered. Logistic regression was used to determine the association between tsetse occurrence and the associated predictors. RESULTS: A total of 39,516 tsetse flies were collected, of which 73.4 and 26.6% were from inside Akagera NP and the interface area, respectively. Female flies accounted for 61.3 while 38.7% were males. Two species were identified, i.e. G. pallidipes [n = 29,121, 7.4 flies/trap/day (FTD)] and G. morsitans centralis (n = 10,395; 2.6 FTD). The statistical difference in numbers was significant between the two species (p = 0.000). The flies were more abundant during the wet season (15.8 FTD) than the dry season (4.2 FTD). Large numbers of flies were trapped around the swamp areas (69.1 FTD) inside the park and in Nyagatare District (11.2 FTD) at the interface. Glossina morsitans was 0.218 times less likely to occur outside the park. The chance of co-existing between the two species reduced outside the protected area (0.021 times). CONCLUSIONS: The occurrence of Glossina seems to be limited to the protected Akagera NP and a narrow band of its surrounding areas. This finding will be crucial to design appropriate control strategies. Glossina pallidipes was found in higher numbers and therefore is conceivably the most important vector of trypanosomosis. Regional coordinated control and regular monitoring of Glossina distribution are recommended.
BACKGROUND:Glossina (tsetse flies) biologically transmit trypanosomes that infect both humans and animals. Knowledge of their distribution patterns is a key element to better understand the transmission dynamics of trypanosomosis. Tsetse distribution in Rwanda has not been well enough documented, and little is known on their current distribution. This study determined the current spatial distribution, abundance, diversity, and seasonal variations of tsetse flies in and around the Akagera National Park. METHODS: A longitudinal stratified sampling following the seasons was used. Biconical traps were deployed in 55 sites for 6 consecutive days of each study month from May 2018 to June 2019 and emptied every 48 h. Flies were identified using FAO keys, and the number of flies per trap day (FTD) was used to determine the apparent density. Pearson chi-square (χ2) and parametrical tests (t-test and ANOVA) were used to determine the variations between the variables. The significance (p < 0.05) at 95% confidence interval was considered. Logistic regression was used to determine the association between tsetse occurrence and the associated predictors. RESULTS: A total of 39,516 tsetse flies were collected, of which 73.4 and 26.6% were from inside Akagera NP and the interface area, respectively. Female flies accounted for 61.3 while 38.7% were males. Two species were identified, i.e. G. pallidipes [n = 29,121, 7.4 flies/trap/day (FTD)] and G. morsitans centralis (n = 10,395; 2.6 FTD). The statistical difference in numbers was significant between the two species (p = 0.000). The flies were more abundant during the wet season (15.8 FTD) than the dry season (4.2 FTD). Large numbers of flies were trapped around the swamp areas (69.1 FTD) inside the park and in Nyagatare District (11.2 FTD) at the interface. Glossina morsitans was 0.218 times less likely to occur outside the park. The chance of co-existing between the two species reduced outside the protected area (0.021 times). CONCLUSIONS: The occurrence of Glossina seems to be limited to the protected Akagera NP and a narrow band of its surrounding areas. This finding will be crucial to design appropriate control strategies. Glossina pallidipes was found in higher numbers and therefore is conceivably the most important vector of trypanosomosis. Regional coordinated control and regular monitoring of Glossina distribution are recommended.
Authors: E Ducheyne; C Mweempwa; C De Pus; H Vernieuwe; R De Deken; G Hendrickx; P Van den Bossche Journal: Prev Vet Med Date: 2009-06-11 Impact factor: 2.670
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Authors: Jennifer S Lord; Stephen J Torr; Harriet K Auty; Paddy M Brock; Mechtilda Byamungu; John W Hargrove; Liam J Morrison; Furaha Mramba; Glyn A Vale; Michelle C Stanton Journal: J Appl Ecol Date: 2018-02-13 Impact factor: 6.528
Authors: Richard Gashururu S; Ndichu Maingi; Samuel M Githigia; Methode N Gasana; Peter O Odhiambo; Dennis O Getange; Richard Habimana; Giuliano Cecchi; Weining Zhao; James Gashumba; Joel L Bargul; Daniel K Masiga Journal: PLoS Negl Trop Dis Date: 2021-12-15