scholarly journals Trypanosome diseases of domestic animals in Nyasaland. III.—Trypanosoma pecorum

1913 ◽  
Vol 87 (592) ◽  
pp. 1-26 ◽  
Keyword(s):  
Central Africa ◽  
Domestic Animals ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Wild Game

This trypanosome has been found in the neighbourhood of the camp at Kasu, in cattle, wild game and wild tsetse flies. In a herd of cattle belonging to the Mvera Mission, which lies about two miles to the east, 32 per cent. were found to be infected by this disease. The mission station is built near the edge of the “fly-country,” and there is little doubt that the cattle were at times exposed to the bite of the “fly.” After the disease had been discovered to be present in the herd the animals were prevented from grazing in the direction of the danger, and since then no new cases have occurred. It is also the species of trypanosome most commonly found in the blood of the wild game in this district, and consequently the tsetse fly is found infected with it more frequently than with any other. It is one of the most important trypanosome diseases of domestic animals in Central Africa, as it affects them all—horses, cattle, goats, sheep, pigs, and dogs. Morphology of Trypanosoma pecorum. The description already given of this species of trypanosome as regards its movements and appearance when alive, its shape, contents of cell, etc., when stained, are applicable to the species as it occurs in Nyasaland and need not be repeated.

scholarly journals Morphology of various strains of the trypanosome causing disease in man in Nyasaland. I.–The human strain

1913 ◽  
Vol 86 (587) ◽  
pp. 285-302 ◽  
Keyword(s):  
East Africa ◽  
Domestic Animals ◽  
Sleeping Sickness ◽  
Tsetse Fly ◽  
General Idea ◽  
Glossina Morsitans ◽  
African Species ◽  
Important Species ◽  
Wild Game

In order to gain a general idea of this important species of trypanosome, it will be necessary to study as many individual strains as possible. It may be thought unnecessary to describe each strain so much in detail, but without this it will be impossible to get any order out of the chaos which rules at present in the classification of the African species of trypanosomes pathogenic to man and the domestic animals. Up to the present the Commission have only had an opportunity of working with five human strains. Four of these are from natives infected in the Sleeping-Sickness Area, Nyasaland, the fifth from an European who contracted the disease in Portuguese East Africa. It is intended, in later papers, to describe five strains from wild game and the same number from the tsetse fly, Glossina morsitans .

scholarly journals Molecular characterization of pathogenic African trypanosomes in biting flies and camels in surra-endemic areas outside the tsetse fly belt in Kenya

2020 ◽  
Author(s):  
Merid N. Getahun ◽  
Jandouwe Villinger ◽  
Joel L. Bargul ◽  
Abel Orone ◽  
John Ngiela ◽  
...  
Keyword(s):  
Domestic Animals ◽  
Trypanosoma Evansi ◽  
Tsetse Fly ◽  
16S Rrna Genes ◽  
Rrna Genes ◽  
Tsetse Flies ◽  
Host Feeding ◽  
Trypanosome Species ◽  
African Trypanosomes ◽  
Northern Kenya

AbstractBackgroundAfrican animal trypanosomosis is becoming prevalent beyond its traditionally defined geographical boundaries and is a threat to animals beyond the tsetse belts in and outside Africa. However, knowledge of infections with clinically important trypanosome species and their diversity among field-collected hematophagous biting flies and domestic animals is limited mainly to tsetse and their mammalian hosts in tsetse-infested areas. This study aimed to examine the presence of trypanosomes in both biting flies and domestic animals outside the tsetse belt in northern Kenya, potential mechanical vector species, and their host-feeding profiles.MethodsWe screened for pathogenic African trypanosomes in blood samples from domestic animals and field-trapped flies by microscopy and sequencing of internal transcribed spacer (ITS1) gene PCR products. We sequenced kinetoplast maxicircle genes to confirm Trypanosoma brucei detection and the RoTat 1.2 and kinetoplast minicircle genes to differentiate type-A and type-B Trypanosoma evansi, respectively. Further, we identified the hosts that field-trapped flies fed on by PCR-HRM and sequencing of 16S rRNA genes.ResultsHippobosca camelina, Stomoxys calcitrans, Tabanus spp., and Pangonia rueppellii are potential vectors of trypanosomes outside the tsetse belt in Marsabit County, northern Kenya. We identified Trypanosoma spp., including Trypanosoma vivax, T. evansi, T. brucei, and T. congolense in these biting flies as well as in camels (Camelus dromedarius). Trypanosomes detected varied from single up to three trypanosome species in H. camelina and camels in areas where no tsetse flies were trapped. Similar trypanosomes were detected in Glossina pallidipes collected from a tsetse-infested area in Shimba Hills, coastal Kenya, showing the wide geographic distribution of trypanosomes. Furthermore, we show that these biting flies acquired blood meals from camels, cattle, goats, and sheep. Phylogenetic analysis revealed diverse Trypanosoma spp. associated with variations in virulence and epidemiology in camels, which suggests that camel trypanosomosis may be due to mixed trypanosome infections rather than only surra (T. evansi), as previously thought.

scholarly journals The use of molecular technology to investigate trypanosome infections in tsetse flies at Liwonde Wild Life Reserve

2020 ◽  
Vol 31 (4) ◽  
pp. 233-237
Author(s):  
Symon F. Nayupe
Keyword(s):  
Central Africa ◽  
Mobile Element ◽  
Conventional Polymerase Chain Reaction ◽  
Tsetse Fly ◽  
Molecular Techniques ◽  
Tsetse Flies ◽  
Lamp Method ◽  
Trypanosome Species ◽  
Animal Trypanosomiasis ◽  
Wild Life

BackgroundTrypanosomes are protozoan flagellates that cause human African trypanosomiasis (HAT) and African animal trypanosomiasis (AAT). HAT is caused by Trypanosoma brucei rhodesiense in East and Central Africa and T.b. gambiense in West Africa, whereas AAT is caused by a number of trypanosome species, including T. brucei brucei, T. evansi, T. vivax, T. congolense, T. godfreyi and T. simiae. The aim of this study was to establish if tsetse flies at Liwonde Wild Life Reserve (LWLR) are infected with these trypanosomes and thus pose a risk to both humans and animals within and surrounding the LWLR. MethodsA total of 150 tsetse flies were caught. Of these, 82 remained alive after capture and were dissected such that the mid-gut could be examined microscopically for trypanosomes. DNA extractions were performed from both mid-guts and the 68 dead flies using a Qiagen Kit. Amplification techniques involved the Internal Transcriber Spacer 1 (ITS 1) conventional polymerase chain reaction (PCR) with primers designed to identify trypanosome species, and Repetitive Insertion Mobile Element – Loop Mediated Isothermal Amplification (RIME LAMP), a sequence specific to T. brucei.ResultsAnalysis showed that 79/82 (96.3%) of the mid-guts examined microscopically were positive for trypanosomes and that 75/150 (50%) of the DNA extracts (from the mid-gut, and tsetse fly carcasses) were positive for T. brucei, as determined by the RIME LAMP method. ITS1 PCR further showed that 87/150 (58.0%) flies were positive for trypanosomes, of which 56/87 (64.4%) were T. brucei, 9/87 (10.3%) were T. vivax; 7/87 (8.1%) were T. simiae; 6/87 (6.9%) were T. congolense, and 6/87 (6.9%) were T. godfreyi. Ten samples had a mixture of infections. ConclusionOur analysis demonstrated a mixture of infections from trypanosome species in tsetse flies at LWLR, and that T. brucei, the species that causes HAT, was the most common. Our study successfully used molecular techniques to demonstrate the presence of T. b. rhodesiense at LWLR, a species that causes HAT in both East and Central Africa.

scholarly journals Trypanosome Infection Rate in Glossina tachinoides: Infested Rivers of Limmu Kosa District Jimma Zone, Western Ethiopia

2019 ◽  
Author(s):  
Behablom Meharenet ◽  
Dereje Alemu
Keyword(s):  
Infection Rate ◽  
Parasite Species ◽  
Domestic Animals ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Trypanosome Infection ◽  
Glossina Tachinoides ◽  
Jimma Zone ◽  
Western Ethiopia ◽  
Trypanosome Infection Rate

Abstract Objective: Trypanosomosis is a disease of domestic animals and humans resulting from infection with parasitaemic protozoa of the genus Trypanosoma transmitted primarily by tsetse flies and other hematophagous flies. The study was conducted to estimate the infection rate of trypanosome in vector flies and involved parasite species. Result: The study result indicated that there was only one species of Tsetse fly Glossinatachinoides detected with high Flay/Trap/Day = 4.45. Total of n=284 tsetse flies were dissected and n= 5 positive for Glossinatachinoidesresulting in 1.76% infection rate. Higher trypanosome infections were observed in female tsetse with significant infection rate of 1.41%, n=4 and 0.35%, n=1 in males. Furthermore, 1.06% of the trypanosome infections carried by Glossinatachinoides were classified as Trypanosomavivax and the remaining 0.70% was Trypanosomacongolense.The study confirmed the absence of human trypanosomosis in study area with only identified trypanosome parasites were Trypanosomavivax and Trypanosomacongolense. However, the resulted FTD= 4.45 recommend control and suppression of the vector and parasite is mandatory due to Pathogenic Animal Trypanosomosis.

scholarly journals Trypanosomes of the domestic animals Nyasaland. I. Trypanosoma simiœ, sp. nov. Part II.—The susceptibility of various animals to T. simiœ

1913 ◽  
Vol 87 (592) ◽  
pp. 48-57 ◽  
Keyword(s):  
Domestic Animals ◽  
Tsetse Flies ◽  
Single Specimen ◽  
Wild Game ◽  
Low Country ◽  
Interesting Species

In a previous paper the morphology of this interesting species of trypanosome was described, and it is now proposed to give an account of its action on animals. One of the first interesting points to be noted about this species is that, as far as is known, the warthog ( Phacochœrus œtheopicus ) is the only animal among the wild game of this district which harbours it. It is probable that it will also be found in the blood of the bush-pig, but not a single specimen of this animal has as yet been obtained by the Commission. The warthog is numerous in the low country in this neighbourhood, which accounts for the large number of tsetse flies found to be infected with Trypanosoma simiœ .

scholarly journals Comparative performance of traps in catching tsetse flies (Diptera: Glossinidae) in Tanzania

2016 ◽  
Vol 83 (1) ◽  
Author(s):  
Imna I. Malele ◽  
Johnson O. Ouma ◽  
Hamisi S. Nyingilili ◽  
Winston A. Kitwika ◽  
Deusdedit J. Malulu ◽  
...  
Keyword(s):  
Glossina Pallidipes ◽  
Abundant Species ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Comparative Performance ◽  
Control Programmes ◽  
Fly Control ◽  
Tsetse Fly Control ◽  
Species Being ◽  
Biconical Traps

This study was conducted to determine the efficiency of different tsetse traps in 28 sites across Tanzania. The traps used were biconical, H, NGU, NZI, pyramidal, S3, mobile, and sticky panels. Stationary traps were deployed at a distance of 200 m apart and examined 72 h after deployment. The results showed that 117 (52.2%) out of the 224 traps deployed captured at least one Glossina species. A total of five Glossina species were captured, namely Glossina brevipalpis, Glossina pallidipes, Glossina swynnertoni, Glossina morsitans, and Glossina fuscipes martinii. Biconical traps caught tsetse flies in 27 sites, pyramidal in 26, sticky panel in 20, mobile in 19, S3 in 15, NGU in 7, H in 2 and NZI in 1. A total of 21 107 tsetse flies were trapped, with the most abundant species being G. swynnertoni (55.9%), followed by G. pallidipes (31.1%), G. fuscipes martinii (6.9%) and G. morsitans (6.0%). The least caught was G. brevipalpis (0.2%). The highest number of flies were caught by NGU traps (32.5%), followed by sticky panel (16%), mobile (15.4%), pyramidal (13.0%), biconical (11.3%) and S3 (10.2%). NZI traps managed to catch 0.9% of the total flies and H traps 0.7%. From this study, it can be concluded that the most efficient trap was NGU, followed by sticky panel and mobile, in that order. Therefore, for tsetse fly control programmes, NGU traps could be the better choice. Conversely, of the stationary traps, pyramidal and biconical traps captured tsetse flies in the majority of sites, covering all three ecosystems better than any other traps; therefore, they would be suitable for scouting for tsetse infestation in any given area, thus sparing the costs of making traps for each specific Glossina species.Keywords: tseste; traps; densties; Glossina; mobile; stationary; Tanzania

scholarly journals Differential virulence and tsetse fly transmissibility of Trypanosoma congolense and Trypanosoma brucei strains

2017 ◽  
Vol 84 (1) ◽  
Author(s):  
Purity K. Gitonga ◽  
Kariuki Ndung’u ◽  
Grace A. Murilla ◽  
Paul C. Thande ◽  
Florence N. Wamwiri ◽  
...  
Keyword(s):  
Survival Time ◽  
Trypanosoma Brucei ◽  
Acute Infection ◽  
Glossina Pallidipes ◽  
Trypanosoma Congolense ◽  
Tsetse Fly ◽  
Economic Losses ◽  
Entire Group ◽  
Tsetse Flies ◽  
African Countries

African animal trypanosomiasis causes significant economic losses in sub-Saharan African countries because of livestock mortalities and reduced productivity. Trypanosomes, the causative agents, are transmitted by tsetse flies (Glossina spp.). In the current study, we compared and contrasted the virulence characteristics of five Trypanosoma congolense and Trypanosoma brucei isolates using groups of Swiss white mice (n = 6). We further determined the vectorial capacity of Glossina pallidipes, for each of the trypanosome isolates. Results showed that the overall pre-patent (PP) periods were 8.4 ± 0.9 (range, 4–11) and 4.5 ± 0.2 (range, 4–6) for T. congolense and T. brucei isolates, respectively (p < 0.01). Despite the longer mean PP, T. congolense–infected mice exhibited a significantly (p < 0.05) shorter survival time than T. brucei–infected mice, indicating greater virulence. Differences were also noted among the individual isolates with T. congolense KETRI 2909 causing the most acute infection of the entire group with a mean ± standard error survival time of 9 ± 2.1 days. Survival time of infected tsetse flies and the proportion with mature infections at 30 days post-exposure to the infective blood meals varied among isolates, with subacute infection–causing T. congolense EATRO 1829 and chronic infection–causing T. brucei EATRO 2267 isolates showing the highest mature infection rates of 38.5% and 23.1%, respectively. Therefore, our study provides further evidence of occurrence of differences in virulence and transmissibility of eastern African trypanosome strains and has identified two, T. congolense EATRO 1829 and T. brucei EATRO 2267, as suitable for tsetse infectivity and transmissibility experiments.

scholarly journals History of Sleeping Sickness in East Africa

1999 ◽  
Vol 12 (1) ◽  
pp. 112-125 ◽  
Author(s):  
Geoff Hide
Keyword(s):  
East Africa ◽  
Molecular Data ◽  
Sleeping Sickness ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
Agricultural Practice ◽  
Molecular Approaches ◽  
History Of ◽  
The Stability ◽  
The Right

SUMMARY The history of human sleeping sickness in East Africa is characterized by the appearance of disease epidemics interspersed by long periods of endemicity. Despite the presence of the tsetse fly in large areas of East Africa, these epidemics tend to occur multiply in specific regions or foci rather than spreading over vast areas. Many theories have been proposed to explain this phenomenon, but recent molecular approaches and detailed analyses of epidemics have highlighted the stability of human-infective trypanosome strains within these foci. The new molecular data, taken alongside the history and biology of human sleeping sickness, are beginning to highlight the important factors involved in the generation of epidemics. Specific, human-infective trypanosome strains may be associated with each focus, which, in the presence of the right conditions, can be responsible for the generation of an epidemic. Changes in agricultural practice, favoring the presence of tsetse flies, and the important contribution of domestic animals as a reservoir for the parasite are key factors in the maintenance of such epidemics. This review examines the contribution of molecular and genetic data to our understanding of the epidemiology and history of human sleeping sickness in East Africa.

scholarly journals Potential impacts of climate change on geographical distribution of three primary vectors of African Trypanosomiasis in Tanzania’s Maasai Steppe: G. m. morsitans, G. pallidipes and G. swynnertoni

2021 ◽  
Vol 15 (2) ◽  
pp. e0009081
Author(s):  
Happiness Jackson Nnko ◽  
Paul Simon Gwakisa ◽  
Anibariki Ngonyoka ◽  
Calvin Sindato ◽  
Anna Bond Estes
Keyword(s):  
Public Health ◽  
Climate Change ◽  
Ecological Niche Modeling ◽  
Tsetse Fly ◽  
Tsetse Flies ◽  
African Trypanosomiasis ◽  
Modeling Tools ◽  
Distribution Maps ◽  
Current Climate ◽  
Maasai Steppe

In the Maasai Steppe, public health and economy are threatened by African Trypanosomiasis, a debilitating and fatal disease to livestock (African Animal Trypanosomiasis -AAT) and humans (Human African Trypanosomiasis—HAT), if not treated. The tsetse fly is the primary vector for both HAT and AAT and climate is an important predictor of their occurrence and the parasites they carry. While understanding tsetse fly distribution is essential for informing vector and disease control strategies, existing distribution maps are old and were based on coarse spatial resolution data, consequently, inaccurately representing vector and disease dynamics necessary to design and implement fit-for-purpose mitigation strategies. Also, the assertion that climate change is altering tsetse fly distribution in Tanzania lacks empirical evidence. Despite tsetse flies posing public health risks and economic hardship, no study has modelled their distributions at a scale needed for local planning. This study used MaxEnt species distribution modelling (SDM) and ecological niche modeling tools to predict potential distribution of three tsetse fly species in Tanzania’s Maasai Steppe from current climate information, and project their distributions to midcentury climatic conditions under representative concentration pathways (RCP) 4.5 scenarios. Current climate results predicted that G. m. morsitans, G. pallidipes and G swynnertoni cover 19,225 km2, 7,113 km2 and 32,335 km2 and future prediction indicated that by the year 2050, the habitable area may decrease by up to 23.13%, 12.9% and 22.8% of current habitable area, respectively. This information can serve as a useful predictor of potential HAT and AAT hotspots and inform surveillance strategies. Distribution maps generated by this study can be useful in guiding tsetse fly control managers, and health, livestock and wildlife officers when setting surveys and surveillance programs. The maps can also inform protected area managers of potential encroachment into the protected areas (PAs) due to shrinkage of tsetse fly habitats outside PAs.

scholarly journals Interpreting Morphological Adaptations Associated with Viviparity in the Tsetse Fly Glossina morsitans (Westwood) by Three-Dimensional Analysis

Insects ◽  
2020 ◽  
Vol 11 (10) ◽  
pp. 651
Author(s):  
Geoffrey M Attardo ◽  
Nicole Tam ◽  
Dula Parkinson ◽  
Lindsey K Mack ◽  
Xavier J Zahnle ◽  
...  
Keyword(s):  
Dimensional Analysis ◽  
Three Dimensional ◽  
Blood Feeding ◽  
Structural Features ◽  
Tsetse Fly ◽  
Reproductive Capacity ◽  
Tsetse Flies ◽  
Sexual Competition ◽  
Morphological Adaptations ◽  
Microscopy Techniques

Tsetse flies (genus Glossina), the sole vectors of African trypanosomiasis, are distinct from most other insects, due to dramatic morphological and physiological adaptations required to support their unique biology. These adaptations are driven by demands associated with obligate hematophagy and viviparous reproduction. Obligate viviparity entails intrauterine larval development and the provision of maternal nutrients for the developing larvae. The reduced reproductive capacity/rate associated with this biology results in increased inter- and intra-sexual competition. Here, we use phase contrast microcomputed tomography (pcMicroCT) to analyze morphological adaptations associated with viviparous biology. These include (1) modifications facilitating abdominal distention required during blood feeding and pregnancy, (2) abdominal and uterine musculature adaptations for gestation and parturition of developed larvae, (3) reduced ovarian structure and capacity, (4) structural features of the male-derived spermatophore optimizing semen/sperm delivery and inhibition of insemination by competing males and (5) structural features of the milk gland facilitating nutrient incorporation and transfer into the uterus. Three-dimensional analysis of these features provides unprecedented opportunities for examination and discovery of internal morphological features not possible with traditional microscopy techniques and provides new opportunities for comparative morphological analyses over time and between species.

Sign in / Sign up

Export Citation Format

Share Document