Molecular identification of different trypanosome species and subspecies in tsetse flies of northern Nigeria

Trypanosomosis is the most serious disease of cattle, which causes great socioeconomic losses in the country. Its socioeconomic impact is reflected on direct losses due to mortality, morbidity, and reduction in milk and meat production, abortion and stillbirth, and also costs associated with combat of the disease are direct losses. A cross-sectional study was carried out to assess the prevalence of cattle trypanosomosis, and the apparent density and distribution of its fly vectors in selected study areas. The methods employed during the study were buffy coat technique for parasitological study and deploying trap for the collection of tsetse flies. A total of 1512 flies were trapped, and among them, 1162 were tsetse flies while 350 were biting flies. Higher apparent density for tsetse fly (7.7 F/T/D) followed by Stomoxys (0.9 F/T/D), Tabanus (0.8 F/T/D), and Hematopota (0.6 F/T/D) was recorded. Out of 638 examined cattle, the overall prevalence of trypanosomosis in the study area was 9.1% (58/638). Out of positive cases, Trypanosoma congolense (7.7%) was the dominant trypanosome species followed by Trypanosoma vivax (0.9%), Trypanosoma brucei (0.2%), and mixed infection of Trypanosoma brucei and Trypanosoma vivax (0.3%). There was no a significant difference (p>0.05) in trypanosome infection between age, sex, and trypanosome species. The prevalence of trypanosomosis on the bases of body condition was 2.8% for poor, 5.5% for medium, and 0.8% for good body condition. The overall prevalence of anemia was (36.8%), and presence of anemia was higher in trypanosome positive animals (62.5%) than in negative animals (34.3%) which is statistically significant (p<0.05, CI = 1.794–5.471). The overall mean packed cell volume (PCV) value for examined animals was 25.84 ± 0.252SE. Mean (PCV) of parasitaemic cattle (9.1%) was significantly (p<0.05) lower than that of aparasitaemic cattle (90%). This survey showed that trypanosomosis is still a core problem for livestock production of the study area. Therefore, more attention should be given to the control of both the disease and its vectors.

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A low Density of Tsetse Flies associated with a high Incidence of Sleeping Sickness

Bulletin of Entomological Research ◽

10.1017/s0007485300005630 ◽

1944 ◽

Vol 35 (1) ◽

pp. 51-51 ◽

Cited By ~ 17

Author(s):

T. A. M. Nash

Keyword(s):

Infection Rate ◽

Extreme Case ◽

Dry Season ◽

Sleeping Sickness ◽

Tsetse Flies ◽

Low Density ◽

Northern Nigeria ◽

High Incidence

In 1935, Dr. Anderson made a sleeping sickness survey of the Kudaru District of Zaria Emirate, Northern Nigeria, where he found a high incidence of the disease. In the extreme case of the small hamlet of Sambo, he recorded a 70 per cent, infection rate among the 43 inhabitants.The writer followed up this survey with an entomological investigation in the late dry season, and paid particular attention to. this hamlet.

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The Trypanosome Infections of Tsetse-flies in Northern Nigeria and a new Method of Estimation

Bulletin of Entomological Research ◽

10.1017/s0007485300028352 ◽

1924 ◽

Vol 14 (3) ◽

pp. 265-288 ◽

Cited By ~ 150

Author(s):

Ll. Lloyd ◽

W. B. Johnson

Keyword(s):

New Method ◽

Tsetse Flies ◽

Northern Nigeria ◽

Trypanosome Infection ◽

Nigerian Government ◽

Entomological Research

The Tsetse Investigation in N. Nigeria is being carried out under the auspices of the Imperial Bureau of Entomology, the expense being met by the Nigerian Government. The work was commenced by the present Investigators in 1921 and their Report dealing with the first year's work was published in the Bulletin of Entomological Research (xiii, p. 373, April 1923). This paper deals more fully with the trypanosome infection of tsetses in Nigeria and describes a method of estimating this with rapidity.

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The ‘White-clubbed’ form of Syntomosphyrum (Hym., Eulophidae) parasitic on tsetse flies

Bulletin of Entomological Research ◽

10.1017/s0007485300054894 ◽

1960 ◽

Vol 51 (1) ◽

pp. 17-20 ◽

Cited By ~ 6

Author(s):

D. S. Saunders

Keyword(s):

Glossina Pallidipes ◽

Distinct Species ◽

Tsetse Flies ◽

Northern Nigeria ◽

Male Progeny ◽

Physiological Barrier

Cross-mating experiments are reported between adults of the typical, darkclubbed form of Syntomosphyrum glossinae Wtstn., obtained from pupae of Glossina pallidipes Aust. from Kenya and of G. palpalis (R.-D.) and G. morsitans submorsitans Newst. from Northern Nigeria, and the ‘white-clubbed’ form of Syntomosphyrum, originally reported by Waterston from Nyasaland, obtained from pupae of G. morsitans Westw. from Tanganyika.Fertilised eggs, giving rise to offspring of both sexes, were produced only by crosses between the strains of typical S. glossinae. Crosses in either direction between the ‘white-clubbed’ form and typical S. glossinae resulted in all-male progeny, presumed to develop from unfertilised eggs. It is considered that this is evidence of a physiological barrier to reproduction between the two forms. The ‘white-clubbed’ form is therefore regarded as a distinct species.

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Apparent density, trypanosome infection rates and host preference of tsetse flies in the sleeping sickness endemic focus of Northwestern Uganda

10.21203/rs.3.rs-43888/v3 ◽

2020 ◽

Author(s):

Robert Opiro ◽

Robert Opoke ◽

Harriet Angwech ◽

Esther Nakafu ◽

Francis A. Oloya ◽

...

Keyword(s):

Infection Rate ◽

Apparent Density ◽

Blood Meal ◽

Nested Pcr ◽

Tsetse Fly ◽

Tsetse Flies ◽

Trypanosome Species ◽

Trypanosome Infection ◽

Infection Rates ◽

Monitor Lizard

Abstract Background: African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies.Methodology: We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, trypanosome infection rates and blood meal sources of tsetse flies. A subset (272) of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results: Out of the 109 traps deployed, we captured 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females). Apparent density (AD) ranged from 0.6 to 3.7 flies/trap/day in the two districts. 29 (10.7%) of the flies were infected with one or more trypanosome species. Infection rate was not significantly associated with neither age group (χ2 = 5.001, df=2, 0.082), sex of the fly (χ2 = 0.099, df = 1, p = 0.753), district of origin (χ2= 0.629, df = 1, p = 0.428) nor village (χ2= 9.252, df = 9, p = 0.414). Nested PCR revealed several species of trypanosomes: T. vivax (6.62%), T. congolense (2.57%), T. brucei and T. simiae each at 0.73%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusio schapini) and the African Savanna elephant (Loxodonta africana).Conclusion: We found an infection rate of 10.78 %, with all infections attributed to trypanosome species that are causative agents for the animal disease only. However, more verification of this finding using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of interventions.

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Apparent density, trypanosome infection rates and host preference of tsetse flies in the sleeping sickness endemic focus of Northwestern Uganda

10.21203/rs.3.rs-43888/v2 ◽

2020 ◽

Author(s):

Robert Opiro ◽

Robert Opoke ◽

Harriet Angwech ◽

Esther Nakafu ◽

Francis A. Oloya ◽

...

Keyword(s):

Infection Rate ◽

Apparent Density ◽

Blood Meal ◽

Nested Pcr ◽

Large Scale ◽

Tsetse Fly ◽

Tsetse Flies ◽

Trypanosome Species ◽

Infection Rates ◽

Monitor Lizard

Abstract Background: African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies.Methodology: We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, infection rates and blood meal sources of tsetse flies. A subset (272) of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results: Out of the 109 traps deployed, we captured 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females). Apparent density (AD) ranged from 0.6 to 3.7 flies/trap/day in the two districts. 29 (10.7%) of the flies were infected with one or more trypanosome species. Infection rate was not significantly associated with neither age group (χ2 = 5.001, df=2, 0.082), sex of the fly (χ2 = 0.099, df = 1, p = 0.753), district of origin (χ2= 0.629, df = 1, p = 0.428) nor village (χ2= 9.252, df = 9, p = 0.414). Nested PCR revealed several species of trypanosomes: T. vivax (6.62%), T. congolense (2.57%), and T. brucei and T. simiae each at 0.73%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusio schapini) and the African Savanna elephant (Loxodonta africana).Conclusion: We found a moderately high infection rate of 10.78%, with all infections attributed to trypanosome species that are causative agents for the animal disease only. However, more validation using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of interventions.

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Apparent density, trypanosome infection rates and host preference of tsetse flies in the sleeping sickness endemic focus of northwestern Uganda

BMC Veterinary Research ◽

10.1186/s12917-021-03071-w ◽

2021 ◽

Vol 17 (1) ◽

Author(s):

Robert Opiro ◽

Robert Opoke ◽

Harriet Angwech ◽

Esther Nakafu ◽

Francis A. Oloya ◽

...

Keyword(s):

Infection Rate ◽

Apparent Density ◽

Blood Meal ◽

Nested Pcr ◽

Large Scale ◽

Tsetse Fly ◽

Tsetse Flies ◽

Trypanosome Species ◽

Trypanosome Infection ◽

Monitor Lizard

Abstract Background African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies. Methodology We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, trypanosome infection status and blood meal sources of tsetse flies. A subset (272) of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results We captured a total of 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females) in the two districts with apparent density (AD) ranging from 0.6 to 3.7 flies/trap/day (FTD). 10.7% (29/272) of the flies were infected with one or more trypanosome species. Infection rate was not significantly associated with district of origin (Generalized linear model (GLM), χ2 = 0.018, P = 0.895, df = 1, n = 272) and sex of the fly (χ2 = 1.723, P = 0.189, df = 1, n = 272). However, trypanosome infection was highly significantly associated with the fly’s age based on wing fray category (χ2 = 22.374, P < 0.001, df = 1, n = 272), being higher among the very old than the young tsetse. Nested PCR revealed several species of trypanosomes: T. vivax (6.62%), T. congolense (2.57%), T. brucei and T. simiae each at 0.73%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusios chapini) and the African Savanna elephant (Loxodonta africana). Conclusion We found an infection rate of 10.8% in the tsetse sampled, with all infections attributed to trypanosome species that are causative agents for AAT. However, more verification of this finding using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of control interventions.

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Apparent Density, Trypanosome Infection Rates and Host Preference of Tsetse Flies in the Sleeping Sickness Endemic Focus of North-Western Uganda

10.21203/rs.3.rs-43888/v1 ◽

2020 ◽

Author(s):

Robert Opiro ◽

Robert Opoke ◽

Harriet Angwech ◽

Esther Nakafu ◽

Francis A. Oloya ◽

...

Keyword(s):

Infection Rate ◽

Apparent Density ◽

Blood Meal ◽

Nested Pcr ◽

Tsetse Fly ◽

Tsetse Flies ◽

Trypanosome Species ◽

Trypanosome Infection ◽

Infection Rates ◽

Monitor Lizard

Abstract Background: African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies.Methodology: We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, trypanosome infection rates and blood meal sources of tsetse flies. A subset of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results: Out of the 109 traps deployed, we captured 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females). Apparent density (AD) ranged from 0.6 to 3.7 flies/trap/day in the two districts. 29 (10.7%) of the flies were infected with one or more trypanosome species, with infection rate significantly associated with age group (χ2 = 29.733, df = 2, p < 0.05) but not with sex (χ2 = 0.43, df = 1, p = 0.835) and district of origin (χ2 = 1.374, df = 1, p = 0.241). Nested PCR revealed several species of trypanosomes: T. vivax (62.1%), T. congolense (24.14 %), and T. brucei and T. simiae each at 6.89%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusio schapini) and the African Savanna elephant (Loxodonta africana).Conclusion: We found a moderately high infection rate at 10.78%, with all infections attributed to trypanosome species that are causative agents for the animal disease only. However, more validation using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of interventions.

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Apparent density, trypanosome infection rates and host preference of tsetse flies in the sleeping sickness endemic focus of Northwestern Uganda

10.21203/rs.3.rs-43888/v4 ◽

2020 ◽

Author(s):

Robert Opiro ◽

Robert Opoke ◽

Harriet Angwech ◽

Esther Nakafu ◽

Francis A. Oloya ◽

...

Keyword(s):

Infection Rate ◽

Apparent Density ◽

Blood Meal ◽

Nested Pcr ◽

Tsetse Fly ◽

Tsetse Flies ◽

Trypanosome Species ◽

Trypanosome Infection ◽

Infection Rates ◽

Monitor Lizard

Abstract Background: African trypanosomiasis, caused by protozoa of the genus Trypanosoma and transmitted by the tsetse fly, is a serious parasitic disease of humans and animals. Reliable data on the vector distribution, feeding preference and the trypanosome species they carry is pertinent to planning sustainable control strategies.Methodology: We deployed 109 biconical traps in 10 villages in two districts of northwestern Uganda to obtain information on the apparent density, trypanosome infection rates and blood meal sources of tsetse flies. A subset (272) of the collected samples was analyzed for detection of trypanosomes species and sub-species using a nested PCR protocol based on primers amplifying the Internal Transcribed Spacer (ITS) region of ribosomal DNA. 34 blood-engorged adult tsetse midguts were analyzed for blood meal sources by sequencing of the mitochondrial cytochrome c oxidase 1 (COI) and cytochrome b (cytb) genes. Results: Out of the 109 traps deployed, we captured 622 Glossina fuscipes fuscipes tsetse flies (269 males and 353 females). Apparent density (AD) ranged from 0.6 to 3.7 flies/trap/day in the two districts. 29 (10.7%) of the flies were infected with one or more trypanosome species. Infection rate was not significantly associated with age group (χ2 = 5.001, df=2, p = 0.082), sex of the fly (χ2 = 0.099, df = 1, p = 0.753), district of origin (χ2= 0.629, df = 1, p = 0.428) and village of origin (χ2= 9.252, df = 9, p = 0.414). Nested PCR revealed several species of trypanosomes: T. vivax (6.62%), T. congolense (2.57%), T. brucei and T. simiae each at 0.73%. Blood meal analyses revealed five principal vertebrate hosts, namely, cattle (Bos taurus), humans (Homo sapiens), Nile monitor lizard (Varanus niloticus), African mud turtle (Pelusio schapini) and the African Savanna elephant (Loxodonta africana).Conclusion: We found an infection rate of 10.78 %, with all infections attributed to trypanosome species that are causative agents for the animal disease only. However, more verification of this finding using large-scale passive and active screening of human and tsetse samples should be done. Cattle and humans appear to be the most important tsetse hosts in the region and should be considered in the design of interventions.

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