Trypanosome Infection Research Articles

Bacterial Pyruvate Kinase: A New Potential Target to Combat Drug‐Resistant Staphylococcus aureus Infections

AbstractSeverity of Infections caused by Staphylococcus aureus ranges from trivial to spine chilling. Irrespective of multiple drugs availability to treat S. aureus infections, increase in drug‐resistance has led to the continuous emergence of resistant strains of all S. aureus including MRSA. Hence, there is an urgent unmet need for novel antibacterial agents to combat multi drug resistant infections which act through unexploited targets/mechanism. Bacterial pyruvate kinase (PK) is one such unique cytoplasmic enzyme crucial in carbohydrate metabolism. It exists in several microorganisms including Mycobacterium sp, P. falciparaum, T. gondii, L. mexicana, V. cholera, etc. In MRSA, PK is an important hub in protein‐protein network with more than 200 interacting partners in a large‐scale protein interaction analysis and might be less susceptible to genetic mutation and resistance due to the network centrality‐lethality criteria. Methicillin resistant S. aureus pyruvate kinase (SAPK) antisense and knockout tests revealed that it is required for growth of MRSA. In recent times, PKs gained attention as potential new targets to combat trypanosomal, leishmanial, malarial and viral infections. This review provides valuable insights about indole alkaloids from natural products and synthetic SAPK inhibitors along with their inhibitory properties against S. aureus and MRSA strains. This review also describes essential structural features and Structure‐Activity Relationship (SAR) for SAPK inhibition.

Prevalence of Trypanosomiasis of Wild Rats (Rattus sp.) in Banjarnegara District and Potential Impact for Public Health

Trypanosomiasis is a zoonotic disease caused by Trypanosoma sp., a protozoan parasite that has a flagellum. It has the potential to cause emerging diseases. Generally, Trypanosoma infection is caused by T. evansi which causes Surra disease, and T. cruzi which causes Chagas disease. Trypanosoma lewisi has been considered a natural protozoan in mice, not pathogenic to humans but in recent years it has been reported in humans. This study aims to detect Trypanosoma in rats in Banjarnegara District and analyze the potential impact on public health. The research was observational with a descriptive approach, conducted in Banjarnegara from July-December 2020. Samples were taken by purposive sampling. Samples are rat’s blood that caught on wild rats survey in the main market of Banjarnegara District. Blood samples were made with a thin smear then they were stained with Giemsa and examined by microscope. There were 157 rats caught, consisting of 131 Rattus norvegicus and 26 R. tanezumi. Totally, 28 rats were positive Trypanosoma lewisi, so Trypanosoma infection in rats in Banjarnegara District is 16,57%. Trypanosomiasis in R. norvegicus was 18.3% and R. tanezumi 15.38%. Therefore, there is a need to increase the awareness of these diseases’s transmission to humans.

Reliability of Some Clinical Parameters for Field Diagnosis of African Animal Trypanosomosis in Cattle

Presumptive and inaccurate diagnosis of cattle trypanosomosis among field veterinarians has led to misuse of trypanocides, development of drug resistance, toxicities and huge economic losses. This study assessed the reliability, specificity and sensitivity of some identified trypanosomosis associated signalments (anaemia using FAMACHA® guide, body condition score (BCS), superficial lymph nodes enlargement and jugular pulsation) as field diagnostic parameters. Blood and faecal samples were collected from 273 subjectively selected cattle for the determination of packed cell volume (PCV) and screening for trypanosome, and for helminth egg using McMaster technique, respectively. Data obtained from assessment of packed cell volume based on BCS, FAMANCHA score, superficial lymph nodes enlargement and jugular pulsation were analyzed using descriptive statistics and Chi square, while comparison of data using independent student ttest and one-way ANOVA was similarly conducted. Of the screened cattle, 16.5% (45/273) were positive for trypanosome. Single infection due to Trypanosoma spp. was found in 13.5% (37/273) cattle, while 2.9% (8/273) had trypanosome concurrently with Babesia spp. or helminth infections. The prevalence of Trypanosoma infection was higher in animals with mild or moderately pale mucous membrane, slight emaciation, palpable superficial lymph nodes and pulsating jugular vein. The mean PCV of Trypanosoma infected cattle (27.65±0.056) was lower than in non-infected cattle (31.30±0.36) (p<0.05). Based on the jugular pulsation status, enlargement of the superficial lymph nodes, trypanosomosis state and Famancha category, there was no significant (p<0.05) variation in the PCV of the examined cattle. A negative and low correlation (r = -0.054) existed between BCS and FAMACHA® anaemia score. Each of the clinical diagnostic parameters showed poor sensitivity when employed separately, but the sensitivity improved when applied together and showed 80% specificity to Trypanosoma infection. The results of the present study showed that Trypanosoma infected cattle were associated with anaemia, emaciation, weight loss, jugular pulsation and lymphadenophathy.
 Key Words: Trypanosomosis, Diagnosis, Cattle, Anaemia, Treatment

Antioxidant and Anti-trypanosomal Activities of the Allium Sativum (Garlic) Bulb Aqueous Extract on Trypanosoma Congolense Infected Mice

Background: Trypanosomes cause the parasitic condition, which is transmitted by tsetse fly. The disease is characterized by intermittent fever, anemia, and frequent diarrhea. This study examined antioxidant and anti-trypanosomal effects of the aqueous extract of garlic in mice. Methods: The extract’s phytochemical screening and antioxidant activity were performed based on standard methods. The acute toxicity was evaluated via Lorke’s method and the anti-trypanosomal effect was evaluated in mice at 100, 250 and 500 mg/kg over 16 days. Results: The screening identified phenols, flavonoids, tannins, alkaloids and saponins. Phenols were present at the highest amount (291.88±6.12 mg/100g) and alkaloids were present the least (13.66±0.03 mg/100g). At 100 µg/mL, the extract quenched 53.20% of the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals with an inhibition concentration (IC50) of 12.44 µg/mL. The lethal dose (LD50) of the extract was determined to be >5000 mg/kg in mice. The extract exhibited high anti-trypanosomal activity at 500 mg/kg and lowered the parasitemia count of 9.7±1.15. This was comparable to the diminazene aceturate activity at 5 mg/kg. The extract at 500 mg/kg significantly increased the packed cell volume and bodyweight of the infected mice. There were no significant differences in many hematological indices comparing the control mice to those that received the extract at 500 mg/kg. Conclusion: The garlic extract had a significant anti-trypanosomes effect and ameliorated the anemic condition induced by infection with trypanosomes. Therefore, the extract may become a therapeutic candidate for the management of trypanosomal infections.

Metabolites From Trypanosome-Infected Cattle as Sensitive Biomarkers for Animal Trypanosomosis.

Trypanosomes are important global livestock and human pathogens of public health importance. Elucidating the chemical mechanisms of trypanosome-relevant host interactions can enhance the design and development of a novel, next-generation trypanosomosis diagnostics. However, it is unknown how trypanosome infection affects livestock volatile odors. Here, we show that Trypanosoma congolense and Trypanosoma vivax infections induced dihydro-β- ionone and junenol, while abundance of dihydro-α-ionone, phenolics, p-cresol, and 3-propylphenol significantly elevated in cow urine. These biomarkers of trypanosome infection are conserved in cow breath and the urine metabolites of naturally infected cows, regardless of population, diet, or environment differences. Furthermore, treating trypanosome-infected cows reduced the levels of these indicators back to the pre-infection levels. Finally, we demonstrated that the potential of some specific biomarkers of phenolic origin may be used to detect active trypanosome infections, including low-level infections that are not detectable by microscopy. The sensitivity and specificity of biomarkers detection are suited for rapid, robust, and non-invasive trypanosomosis diagnosis under field conditions.

Molecular detection of Trypanosoma spp. and Hepatocystis parasite infections of bats in Northern Nigeria.

Bats are mammalian hosts to a large diversity of eukaryotic protozoan blood parasites, including different genera of haemosporidians and diverse species of trypanosomes. Phylogenetic studies suggest that bats, particularly in Africa, have played an important role in the evolutionary histories of these parasite groups. However, our understanding of the diversity and distribution of chiropteran haemosporidians and trypanosomes in Africa remains tenuous. We investigated the prevalence and phylogenetic relationships of the blood parasites in different bat species in Northern Nigeria using molecular methods. A low prevalence of Hepatocystis parasites was detected in a potentially rare host species, the African straw-coloured fruit bat (Eidolon helvum) confirming yet another fruit bat species in the diverse range of African bat hosts. Trypanosome infections were identified in 3 different bat species. The trypanosomes of Mops cf. pumilus were recovered as a distinct lineage that is related to Trypanosoma erneyi, a species which is closely related to Trypanosoma dionisii and Trypanosoma cruzi. Nycteris cf. macrotis bats were infected with trypanosomes that are related to the distinct lineage of Trypanosoma cf. livingstonei parasites. Further, 2 different lineages of trypanosomes in E. helvum bats share highest nucleotide identities with Trypanosoma livingstonei and a group of Trypanosoma sp. parasites that are closely related to T. cf. livingstonei and T. livingstonei, respectively. The findings of this study confirm the notion that trypanosomes of African bats are phylogenetically diverse and that African bats might harbour a variety of yet undescribed trypanosome species.

Molecular survey of Trypanosoma congolense “Forest-Type” in Nigerian cattle

African animal trypanosomosis is an important livestock disease in Nigeria which is considered as a threat to the on-going effort on poverty alleviation in the continent. The disease is caused by several Trypanosoma species which are protozoan parasites transmitted by tsetse. Trypanosomosis is characterized by tissue injury including overwhelming activation of Classical Myeloid cells that results in destruction of the liver and uncontrolled parasite growth. Reduction in production and sometimes death are disease sequella. Hence, proper surveillance of the disease using a sensitive tool is very necessary for monitoring and control of trypanosomosis. Therefore this study concentrated on providing knowledge on the true infection rate of Trypanosoma congolense “forest type” and its effect on body weight and haematological parameters. Blood sample was collected from 180 cattle, DNA was extracted and PCR technique was adopted for prevalence study. Haematological analysis was carried out using Auto-haemo-analyser. Data generated were analysed using SAS statistical package. A prevalence rate of 91.67% was recorded. There were significant (p<0.05) differences between Body-weight, Red Blood Cell count, Mean Corpuscular Volume and Monocyte number of infected and un-infected cattle. The haematology reveals that hosts were able to respond to anaemia compensatorily as perceived in the macro-cytic, normo-chromic status of the peripheral blood erythrocytic generation. The study concluded that the true prevalence of trypanosome infection is high and has both epidemiological and economic importance. This study `provides information that could facilitate future monitoring and control of the disease in the study area.

Parasitological and molecular identification of Trypanosoma species circulating in cattle and tsetse flies in Matutuine District, Maputo Province, Mozambique

Tsetse flies (Diptera: Glossinidae) are haematophagous insects of medical and veterinary importance due to their role in the transmission of trypanosomes. Tsetse-transmitted trypanosomosis is one of the major constraints to agriculture and livestock development in sub-Saharan Africa. Thus, the importance of the assessment of the distribution of both disease and vector in areas where cattle are kept, as is the case of Matutuíne district, where the last longitudinal study was conducted in 2000. From March 2009 to December 2012, 2427 bovine blood samples were collected in five administrative areas of Matutine district (Bela Vista, Zitundo, Catuane, Catembe and Machangulo). For each animal, the packed cell volume (PCV) was determined and blood examined for the presence of motile trypanosomes using microscopy. At the same time, tsetse flies were also captured. Additionally, DNA was extracted from both cattle blood and tsetse flies. The samples were further analysed using the 18S PCR–RFLP. Trypanosome infections in bovines were detected in all Matutuíne´s administrative areas. The overall prevalence of trypanosome infections was 15.62% by buffy coat and 47.34% by molecular testing. A total of 1379 tsetse flies (1379 Glossina brevipalpis and 150 G. austeni) were captured. From this, 408 were analysed by 18S PCR for the presence of trypanosomes. The results showed a percentage of infection of 12.74% and 3.19% for G. brevipalpis and G. austeni, respectively. With these results, it is concluded that tsetse-transmitted trypanosomosis is a major threat to cattle in Matutuine and control actions need to be implemented.

A review on therapeutic activities of diminazene aceturate

Diminazene aceturate is the drug most commonly used for the treatment of trypanosome infections in cattle, sheep and goat. It has been reported to also have anti-babesial, anti-inflammatory, anthelmintic, anti-viral and anti-bacterial activities unlike other trypanocides. The drug is an aromatic diamidine compound popularly marketed as Berenil®. Retention of high concentrations of diminazene aceturate in plasma and tissues can be enhanced by combining it with other drugs such as Oxytetracycline long-acting. The enhanced concentrations can lead to prevention of relapse of treated trypanosome infections and it can also act as a prophylactic treatment against trypanosomosis in dogs. The present review discussed current status of knowledge concerning therapeutic spectrum of diminazene, its chemical structure, physical properties, mechanism of actions, contraindications, formulations and combination therapeutic regimens in which diminazene has been administered together with other compounds. Analytical techniques for diminazene, the pharmacokinetics of diminazene, its toxicity, and clinical uses in livestock are also discussed.

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 Wolbachia and Sodalis bacteria, in tsetse flies infected with trypanosomes (Trypanosoma vivax, Trypanosoma congolense and Trypanosoma brucei). Out of 278 captured tsetse flies in eastern Zambia, 95.3% (n = 265, 95% CI = 92.8–97.8) carried endosymbionts: Wolbachia (79.1%, 95% CI 73.9–83.8) and Sodalis (86.3%, 95% CI 81.7–90.1). Overall, trypanosome prevalence was 25.5% (n = 71, 95% CI = 20.4–30.7), 10.8% (n = 30, 95% CI 7.1–14.4) for T. brucei, 1.4% (n = 4, 95% CI = 0.4–3.6) for both T. congolense and T. vivax, and 0.7% (n = 2, 95% CI 0.1–2.6) for T. b. rhodesiense. Out of 240 tsetse flies that were infected with Sodalis, 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 Wolbachia infected tsetse flies were infected with trypanosomes. There was 1.3 times likelihood of T. brucei infection to be present when Wolbachia was present and 1.7 likelihood of T. brucei infection when Sodalis 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.

A review on therapeutic activities of diminazene aceturate

Diminazene aceturate is the drug most commonly used for the treatment of Trypanosome infections in cattle, sheep and goat. It has been reported to also have anti-babesial, anti-inflammatory, anthelmintic, anti-viral and anti-bacterial activities unlike other trypanocides. The drug is an aromatic diamidine compound popularly marketed as Berenil®. Retention of high concentrations of diminazene aceturate in plasma and tissues can be enhanced by combining it with other drugs such as Oxytetracycline long acting. The enhanced concentrations can lead to prevention of relapse of treated trypanosome infections and it can also act as a prophylactic treatment against trypanosomosis in dogs. The present review discussed current status of knowledge concerning therapeutic spectrum of diminazene, its chemical structure, physical properties, mechanism of actions, contraindications, formulations and combination therapeutic regimens in which diminazene has been administered together with other compounds. Analytical techniques for diminazene, the pharmacokinetics of diminazene, its toxicity, and clinical uses in livestock are also discussed.

DETECTION OF T. VIVAX AND T. CONGOLENSE IN CATTLE FROM SELECTED ABATTOIRS IN KADUNA METROPOLIS, KADUNA STATE, NIGERIA.

African trypanosomiasis is disease caused by protozoan parasite in sub-Saharan Africa that affects human and animals. In animals it causes serious economic loss in livestock as a result of anaemia, loss of appetite and emaciation and when not treated death occurs. This study therefore, was aimed at detecting T. vivax and T. congolense in cattle from selected abattoirs in Kaduna State using the conventional wet mount technique and PCR. A total of 300 blood samples were obtained from the study area with 100 samples from each of three abattoirs. Out of the 300 samples, 64 were positive at a prevalence of 21.3% using wet mount, while for individual abattoir, the lowest prevalence was observed in Makera at 5.0% for 15 cows, Kawo at 5.7% for 17 cows; while Tudun-wada recorded the highest prevalence of 10.7% for 32 cows, respectively. T. congolense recorded a higher prevalence when compared to T. vivax with 17% for the former and 4.3% for the latter. Seventeen positive blood samples were randomly selected and subjected to PCR to confirm the presence of the parasites using specific primers. In addition to confirming the presence of both parasites with the PCR, false positive result were detected in the gel picture after electrophoresis compared to the earlier result of the microscopy. In conclusion, microscopy and PCR should be used complimentarily for the confirmatory diagnosis of trypanosomal infection in cattle in order to carry out effective prophylactic and therapeutic control measures and curb the menace of this neglected tropical disease.

Molecular Analysis of Trypanosome Infections in Algerian Camels

PurposeSurra is an economically important livestock disease in many low- and middle-income countries, including those of Northern Africa. The disease is caused by the biting fly-transmitted subspecies Trypanosoma brucei evansi, which is very closely related to the tsetse-transmitted subspecies T. b. brucei and the sexually transmitted subspecies T. b. equiperdum. At least two phylogenetically distinct groups of T. b. evansi can be distinguished, called type A and type B. These evolved from T. b. brucei independently. The close relationships between the T. brucei subspecies and the multiple evolutionary origins of T. b. evansi pose diagnostic challenges.MethodsHere we use previously established and newly developed PCR assays based on nuclear and mitochondrial genetic markers to type the causative agent of recent trypanosome infections of camels in Southern Algeria.Results/conclusionWe confirm that these infections have been caused by T. b. evansi type A. We also report a newly designed PCR assay specific for T. b. evansi type A that we expect will be of diagnostic use for the community.

Spatial Distribution of Tsetse Flies and Trypanosome Infection Status in a Vector Genetic Transition Zone in Northern Uganda.

Background Tsetse flies are vectors of the genus Trypanosoma that cause African trypanosomiasis, a serious parasitic disease of people and animals. Reliable data on the vector distribution and the trypanosome species they carry is pertinent for planning sustainable control strategies. This study was carried out to estimate the spatial distribution, apparent density, and trypanosome infection rates of tsetse flies in two districts that fall within a vector genetic transition zone in northern Uganda. Materials and Methods Capturing of tsetse flies was done using biconical traps deployed in eight villages in Oyam and Otuke, two districts that fall within the vector genetic transition zone in northern Uganda. Trapped tsetse flies were sexed and morphologically identified to species level and subsequently analyzed for detection of trypanosome DNA. Trypanosome DNA was detected using a nested PCR protocol based on primers amplifying the internal transcribed spacer (ITS) region of ribosomal DNA. Results A total of 717 flies (406 females; 311 males) were caught, all belonging to the Glossina fuscipes fuscipes species. The overall average flies/trap/day (FTD) was 2.20 ± 0.3527 (mean ± SE). Out of the 477 (201 male; 276 females) flies analyzed, 7.13% (34/477) were positive for one or more trypanosome species. Three species of bovine trypanosomes were detected, namely, Trypanosoma vivax, 61.76% (21/34), T. congolense, 26.47% (9/34), and T. brucei brucei, 5.88% (2/34), and two cases of mixed infection of T. congolense and T. brucei brucei, 5.88% (2/34). The infection rate was not significantly associated with the sex of the fly (generalized linear model (GLM), χ2 = 0.051, p = 0.821, df = 1, n = 477) and district of origin (χ2 = 0.611, p = 0.434, df = 1, n = 477). However, trypanosome infection was highly significantly associated with the fly's age based on wing fray category (χ2 = 7.56, p = 0.006, df = 1, n = 477), being higher among the very old than the young. Conclusion The relatively high tsetse density and trypanosome infection rate indicate that the transition zone is a high-risk area for perpetuating animal trypanosomiasis. Therefore, appropriate mitigation measures should be instituted targeting tsetse and other biting flies that may play a role as disease vectors, given the predominance of T. vivax in the tsetse samples.

Assessing the Tsetse Fly Microbiome Composition and the Potential Association of Some Bacteria Taxa with Trypanosome Establishment.

The tsetse flies, biological vectors of African trypanosomes, harbour a variety of bacteria involved in their vector competence that may help in developing novel vector control tools. This study provides an inventory of tsetse bacterial communities in Cameroon and explores their possible associations with trypanosome establishment in Glossina palpalis palpalis. High throughput sequencing of the V3-V4 hypervariable region of the bacterial 16S rRNA gene, with subsequent metagenomic, multivariate, and association analyses, were used to investigate the levels and patterns of microbial diversity in four tsetse species. Overall, 31 bacterial genera and four phyla were identified. The primary symbiont Wigglesworthia dominated almost all the samples, with an overall relative abundance of 47.29%, and seemed to be replaced by Serratia or Burkholderia in some G. tachinoides flies. Globally, significant differences were observed in the microbiome diversity and composition among tsetse species and between teneral and non-teneral flies, or between flies displaying or not displaying mature trypanosome infections. In addition, differential abundance testing showed some OTUs, or some bacteria taxa, associated with trypanosome maturation in tsetse flies. These bacteria could be further investigated for an understanding of their mechanism of action and alternatively, transformed and used to block trypanosome development in tsetse flies.

Structure, function and druggability of the African trypanosome flagellum.

African trypanosomes are early branching protists that cause human and animal diseases, termed trypanosomiases. They have been under intensive study for more than 100 years and have contributed significantly to our understanding of eukaryotic biology. The combination of conserved and parasite‐specific features mean that their flagellum has gained particular attention. Here, we discuss the different structural features of the flagellum and their role in transmission and virulence. We highlight the possibilities of targeting flagellar function to cure trypanosome infections and help in the fight to eliminate trypanosomiases.

Risk factors for equine trypanosomosis and hematological analysis of horses in Paraguay

Animal trypanosomosis, caused by Trypanozoon trypanosomes (Trypanosoma evansi and T. equiperdum), and Trypanosoma vivax, is endemic to South American countries and has a negative impact on the livestock industry. However, the risk factors for trypanosomosis in Paraguay remain unknown. This study aimed to determine the risk factors for equine trypanosomosis in Paraguay based on a PCR-based molecular survey and individual horse sampling data. In this study, 739 blood samples were collected from horses in 16 departments of Paraguay between August 2019 and November 2020. To elucidate the risk factors for trypanosome infection, the relationship between trypanosome infection status detected by PCR and the location, sex, age, breed of horses, and season of sample collection was analyzed. There were no significant differences in trypanosome prevalence in horses between the eastern and western regions, ages, or breeds of horses in Paraguay. Sex and season were identified as risk factors for trypanosome infection in horses in Paraguay in the current study. These results suggest that the rainy-summer season, when vectors increase in number and their blood-sucking activity, could be the most important risk factor for trypanosome infection in Paraguay horses. Preventive measures and treatments should be developed to address these factors.

Detection of Trypanosoma Infection in Dromedary Camels by Using Different Diagnostic Techniques in Northern Oman.

Simple SummaryThe camel is a salient character of the pastoral economy around the world. Apropos of this title role, the camel plays a particularly crucial role in arid and semi-arid areas of the world. The camel population is growing despite much urbanization around the world. The importance of the camel concerns the acquisition of milk, meat and other byproducts. Due to emerging health issues, people mainly rely on camel milk and meat due to their remedial purposes, hence why it is held in high regard. Therefore, it is crucial to take into consideration the camels’ health, risks, associated diseases and diagnoses. In this investigation, an effort was made to detect trypanosomoses in dromedary camels by using different diagnostic techniques in Northern Oman.Camel trypanosomoses is considered a devastating disease with severe health consequences that can be caused by different hemoprotozoan parasites. Camel samples (388) from the five regions in Northern Oman were assessed using a thin blood film. In addition, 95 seropositive samples were analyzed using various primers of mechanically transmitted trypanosomes. Out of the 388 blood smears examined, 0.8% (CI 95%, 2/388) were found to be positive for Trypanosoma sp. using a microscope. The parasitologically positive cases were detected in samples from females. The overall molecular prevalences were as follows: TBR was 78/95, 77% (CI 73.1–89.2%); ITS was 30/95, 31.6% (CI 73.1–89.2%); and T. evansi type A (RoTat 1.2) was 8/95, 8.4% (CI 4.0–16.0%). There were two species of trypanosomes that were observed in the camels.

Environmental mutations in the Campo focus challenge elimination of sleeping sickness transmission in Cameroon.

Sleeping sickness is still prevalent in Campo, southern Cameroon, despite the efforts of World Health Organization and the National Control Programme in screening and treating cases. Reducing disease incidence still further may need the control of tsetse vectors. We update entomological and parasitological parameters necessary to guide tsetse control in Campo. Tsetse flies were trapped, their apparent densities were evaluated as the number of flies captured per trap per day and mapped using GIS tools. Polymerase chain reaction based methods were used to identify their trypanosome infection rates. Glossina palpalis palpalis was the dominant vector species representing 93.42% and 92.85% of flies captured respectively during the heavy and light dry seasons. This species presented high densities, that is, 3.87, 95% CI [3.84-3.91], and 2.51, 95% CI [2.49-2.53] flies/trap/day in the two seasons. Moreover, 16.79% (of 1054) and 20.23% (of 1132 flies) were found infected with at least 1 trypanosome species for the 2 seasons respectively, Trypanosoma congolense being the most prevalent species, and Trypanosoma. brucei gambiense identified in 4 samples. Tsetse flies are abundant in Campo and present high trypanosome infection rates. The detection of tsetse infected with human trypanosomes near the newly created palm grove show workers' exposition. Tsetse densities maps built will guide vector control with 'Tiny Targets'.

The prevalence of trypanosome infections in goats at Niassa National Reserve, Mozambique

African animal trypanosomosis (AAT), a debilitating tsetse-transmitted parasitic disease, is a major constraint to livestock ruminant production in Sub-Saharan Africa. In the southern Africa region, the main Trypanosoma species causing AAT include T. brucei, T. vivax and T. congolense. All three species have been described in acute, subacute, chronic or subclinical cases of AAT in goats. In the tsetse belt region, goat infections are estimated at 40 million per year. Despite this, the role of these small ruminants in the epidemiology of AAT is yet to be fully understood. To determine trypanosome prevalence and contribute to the understanding of the role of these small ruminants in the epidemiology of trypanosomosis, at Niassa National Reserve (NNR), a cross-sectional survey was conducted between July and September 2018 in five districts located inside the NNR (Sanga, Mavago, Majune, Marrupa and Mecula), Niassa Province, Mozambique. A total of 416 goat blood samples were collected and screened for trypanosomes using microscopy and Polymerase Chain Reaction (PCR). The overall prevalence was 0.96%, out of which, 0.72% corresponded to T. congolense and 0.24% to T. vivax. Mecula was the district with the highest prevalence (0.48%), followed by Sanga and Majune (both with 0.24%). Considering the aforementioned results, the role of goats in the epidemiology of the disease, within the NNR, may be considered negligible.