Surveillance and control of Trypanosoma evansi in the canary Islands: A descriptive analysis.

This study examines the occurrence of Surra, a disease caused by Trypanosoma evansi, in camels in the Canary Islands. The 1997 detection of T. evansi in camels in the Canary Islands led to the implementation of an initial control program, resulting in a decrease in prevalence. Following an outbreak in 2014, and due to the impossibility of eradicating it using the conventional measures, a lazaret was set up to separate positive and suspicious animals, in addition to the control measures previously implemented. Stomoxys calcitrans was the only vector captured, and no other animals tested were found to be positive for T. evansi. In November 2019, the last camels that tested serologically positive were detected; however, since February 2018, no camels that tested positive for PCR have been found in the farms were the outbreak was detected, suggesting that the sanitary measures implemented are adequate. The duration of the outbreak control and potential eradication for the disease has yet to be established. This study provides evidence to facilitate the control of African Animal Trypanosomosis in endemic areas of the world, which may contribute to revise the World Organization for Animal Health (WOAH) protocol to implement recommendations of surveillance and control strategies for animal Trypanosomosis in camels.

Morphological, serological, molecular detection, and phylogenetic analysis of Trypanosoma evansi in horses of different regions in Iran.

Trypanosoma evansi, the causative agent of "surra" is enzootic in Iran. The current study aimed to detect T. evansi in horses from different regions of Iran using morphological, serological, and molecular methods. In 2021, 400 blood samples were collected from horses in eight regions. Eighty horses showed clinical signs such as cachexia (n = 64), fever (n = 36), foot edema (n = 40), and abdominal edema (n = 32), and 320 horses appeared healthy. All samples from the studied regions were evaluated for the presence of trypanosomes using direct analysis of blood smears, mercuric chloride, and PCR-based tests. In total, 12% (95% CI: ± 3.1%), 21% (95% CI: ± 3.9%), and 21% (84) of animals were positive for Trypanosoma in microscopic, serologic, and molecular analyses, respectively. All animals positive for SSU rDNA PCR were from Qom, Semnan, and Golestan regions. Further molecular analyses on 84 PCR-positive horses revealed that 29 horses scored positive in PCR using primers of trypanozoon species and 5 scored positive in PCR using primers of Trypanosoma evansi type A. All samples (n = 5) were from Qom region. The 205-bp fragments of T. evansi RoTat 1.2VSG (accession numbers: ON017789-93) analyzed and compared to other isolates sequence from GenBank BLAST search. It has close similarities with isolates from Pakistan, Egypt, Malaysia, Kenya, and India. Data herein demonstrated that horses from Iran were at high risk of T. evansi infection. Comprehensive control programs, such as those based on the application of repellants and traps, and also, compliance with quarantine standards are recommended for minimizing the risk of the infection.

Parasitological, molecular, and epidemiological investigation of Trypanosoma evansi infection among dromedary camels in Balochistan province.

Surra is a zoonotic disease caused by Trypanosoma evansi (T. evansi), which affects a wide variety of animals worldwide. The disease has a severe impact on the productivity, health, and working capacity of camels and causes mortality and extensive economic losses if not diagnosed early. This is the first comprehensive report on the prevalence of T. evansi infection in dromedaries in Balochistan province. In the present study, 393 blood samples (indigenous, n = 240; imported, n=153) were collected from one-humped camels (Camelus dromedarius) and were tested by molecular methods to estimate the prevalence of T. evansi in three districts (Pishin, Nushki, and Lasbella) of Balochistan province. The overall prevalence of T. evansi among examined camel samples was 28.24% (95% confidence interval (CI): 24.02-32.89%). The risk of T. evansi infection in adult camels (> 10 years) is higher than that in young ones (odd-ration (OR) = 2.7; 95% CI: 1.3357-5.3164%). Moreover, male camels were six times more likely to get an infection than female camels. The detection of T. evansi infection in camels sampled in summer and spring was 3.12- and 5.10-fold higher, respectively, than in camels sampled in winter. In conclusion, our findings showed a high rate of T. evansi infection in camels from the three districts. Our study emphasizes the need for a strict surveillance program and risk assessment studies as prerequisites for control measures.

Parasitological and molecular detection of Trypanosoma evansi in a dog from Tocache, San Martin, Peru.

This study presents the first case report of canine trypanosomiasis caused by Trypanosoma evansi in Peru. The case was admitted to a veterinary clinic in the Peruvian Amazon region of San Martin with severe clinical symptomatology which resulted in the dog's death. Microscopy screening showed the presence of trypomastigotes in blood and bone marrow and postmortem histopathology found damage at the cardiac, lung, kidney and spleen levels. Collected specimens were tested by nested-PCR which were positive for Trypanosoma spp., but negative for T. cruzi. High-throughput sequencing determined that the infecting species was closely related to T. equiperdom/evansi and subsequent phylogenetic analysis confirmed that the sample was related to T. evansi. The presence of T. evansi in the area highlights the need for increased surveillance to assess the impact of surra in the region and to develop measures to prevent socioeconomic damage resulting from infections in domestic and farm animals as well as prevent zoonotic transmission.

Prevalence and Risk Factors Associated With Natural Infection by Trypanosoma evansi in Campeiro Horses.

Campeiro horse is a breed locally adapted to the Santa Catarina plateau region and its main characteristic is the gait, it is known as "Marchador das Araucárias." It is a breed considered in danger of extinction, being fundamental the search for the preservation of this important genetic resource. Surra, caused by the protozoan Trypanosoma evansi, is among the diseases that affect horses. However, there are no data on the prevalence of infection in Campeiro horses. This study aimed to determine the prevalence of T. evansi in Campeiro horses, correlate hematology and serum biochemistry, and identify possible risk factors. Blood samples were collected by venipuncture of 214 Campeiro horses, 50 males and 164 females, aged between 3 months and 27 years, from 16 properties located in the States of Santa Catarina, Rio Grande do Sul, and Paraná. An epidemiological questionnaire was carried out with the owners to analyze the associated risk factors. The blood samples were submitted to polymerase chain reaction, immunofluorescence antibody test, complete blood count, and serum biochemistry. The prevalence was 14% of positive animals by polymerase chain reaction and 59% by immunofluorescence antibody test . There was an increase in hematocrit, and in the number of basophils, a decrease in plasmatic fibrinogen, and in the enzymatic activity of alanine aminotransferase, aspartate aminotransferase, and urea, and an increase in creatine phosphokinase and creatinine in positive animals, which is possibly unrelated to the infection. The data obtained through the epidemiological questionnaires showed no difference. Therefore, T. evansi is present in the South of Brazil, with a high prevalence in Campeiro horses.

Circulation of Trypanosoma evansi antibodies and risk variables among dromedary camels in Al Batinah governorates, Sultanate of Oman.

Trypanosoma evansi is a blood protozoan infects camels with Surra disease and causes high economic losses. The current study was focused on estimating the seroprevalence and associated risk factors of Surra disease among camels, using 425 blood samples collected from 45 farms in nine Wilayats of Al Batinah governorates in the Sultanate of Oman. Host and environmental risk factors associated with T. evansi seroprevalence were analyzed by questionnaire arranged during sample collection. The overall seroprevalence by the serological CATT/T. evansi was 19.5% (83/425, CI: 16.0-23.6%). The seroconversion rate between the two governorates of north and south Al Batinah was not statistically significant (p > 0.05). However, the highest frequency was in Al Musannah at 41.7% (10/24, CI: 22.1-63.4%), and the lowest was in Al Khaburah at 10.5% (6/57, CI: 4.0-21.5%). Most of the owners in Al Khaburah (82.5%) were aware of T. evansi importance, and therefore they kept camels separate from ruminants. The ticks-free camels, racing camels and camels less than five years old showed higher T. evansi seroprevalence than other camels. The mean total protein was significantly (t = 2.817, p = 0.006) higher in seropositive camels (6.49 ± 0.75) compared to seronegative ones (6.25 ± 0.55), whereas PCV was not statistically different between the positive (28.96 ± 4.33) and negative camels (29.83 ± 3.63). Further studies are highly recommended to determine the prevalence and type of T. evansi in camels and ruminants in different governorates in Oman, especially in the Dhofar region, where the highest camel density is reported in the country.

In vitro and in vivo evaluation of kinase and protease inhibitors against Trypanosoma evansi.

Trypanosoma evansi is a causative agent of chronic wasting and fatal disease of livestock and wild animals known as surra. In this study, repurposing approach based on drug target was used to investigate the efficacy of kinase inhibitors (Barasertib-HQPA, BAR and Palbociclib isethionate, PAL) and protease inhibitors (Z-pro-prolinal, Z-PRO and Leupeptin hemisulphate, LEU) against T. evansi in HMI-9 medium. BAR, PAL and Z-PRO exhibited IC50 values of 13.52 µM, 0.6375 µM and 63.20 µM against T. evansi in terms of growth inhibition, in the contrary, LEU failed to exhibit a significant growth inhibition at any time interval. Furthermore, oligopeptidase B and aurora kinase genes of T. evansi were targeted to determine the effect of these drugs on quantitative mRNA expression, which showed significant (p < 0.01) up-regulation of both genes in the BAR and PAL-exposed population at 12 h of exposure, whereas, Z-PRO showed only significant (p < 0.05) up-regulation of aurora kinase gene at 12 h interval. In cytotoxicity assay, BAR exhibited 52% and 41% cytotoxicity at 50 µM concentration (about five folds the IC50 value) on equine PBMC's and Vero cell line, respectively. Similarly, the cytotoxicity of 25% and 24% were recorded at 10 µM concentration (about ten folds to the IC50 value) of PAL in equine PBMC's and Vero cell line, respectively. Of these, BAR and PAL, which were found effective under in vitro trials, raised the longevity of mice at higher doses during in vivo trials. Data generated showed that kinase inhibitors have higher potential to explore therapeutic molecules against surra organism.

Recent Progress in the Detection of Surra, a Neglected Disease Caused by Trypanosoma evansi with a One Health Impact in Large Parts of the Tropic and Sub-Tropic World.

Surra is a wasting disease triggered by infection with Trypanosoma evansi, a protozoan blood parasite that causes mortality and morbidity in a broad spectrum of wild and domestic animals and occasionally humans. Trypanosoma evansi has the widest geographical spread among all pathogenic trypanosomes, inflicting significant worldwide economic problems due to its adverse effects on meat and milk production. For diagnosis, most endemic countries continue to rely on traditional parasitological and serological techniques, such as the analysis of blood smears by microscopy and the Card Agglutination Test for T. evansi (CATT/T. evansi). Although these techniques suffer from a limited positive predictive value (PPV), resource constraints in endemic countries often hinder the adoption of more advanced diagnostic tools such as PCR. This paper addresses diverse diagnostic approaches for identifying T. evansi and assesses their viability in field settings. Moreover, it underscores the urgency of transitioning towards molecular diagnostic techniques such as Loop-Mediated Isothermal Amplification (LAMP) and Recombinase Polymerase Amplification (RPA) for dependable high-PPV point-of-care (POC) diagnostics. Finally, this review delves into strategies to enhance and refine next-generation diagnostics for Surra as part of a One Health approach.

Immunosorbent assay for detection of Trypanosoma evansi infection in multiple host species using chimeric protein A/G conjugate.

Surra caused by an extracellular hemoflagellate, Trypanosoma evansi, leads to severe economic loss to livestock productivity in India. Among the various mammalian pathogenic trypanosomes, T. evansi has the widest host range.Usually, species specific conjugates are used in conventional indirect immunosorbent assay (ELISA) for diagnosis of T. evansi infection in different animal species. The aim of the study was to explore the use of non-species specific conjugates viz., protein A, G and chimeric protein A/G instead of species specific conjugates for development of indirect ELISAs. These assays were used for detection of antibodies against T. evansi infection in multiple animal species viz., equine, cattle, buffalo, dog, pig and camel. The functional affinities of serum immunoglobulins of six different animal species with different conjugates were determined by estimation of relative avidity index (RAI). The species specific conjugate based whole cell lysate- T. evansi antigen ELISA was considered as reference assay for comparison of sensitivity and specificity of non-species specific conjugates based ELISAs optimized in the present study. Data showed that serodiagnosis of T. evansi can be carried out by using chimeric protein A/G conjugate in multiple hosts viz., equine, buffalo, camel, pig and dog; protein G conjugate in equine and buffalo and protein A conjugate in camel, pig and dog. The relative diagnostic sensitivity and specificity for chimeric protein A/G conjugate varied from 60 to 100% and 79-100%, respectively for different livestock species. This approach might be helpful in monitoring and surveillance of T. evansi infection in multiple hosts in particular when host specific secondary antibody conjugates are not available. Investigations should be made in wild animals and other warm-blooded vertebrates to validate this hypothesis.

Comparison of ITS-1 and TBR-1/2 primer sensitivity for the detection of Trypanosoma evansi local isolates in experimental rats using a polymerase chain reaction.

Background and Aim: Surra is caused by Trypanosoma evansi. The detection method using conventional parasitological tests has not always shown positive results in blood parasite detection, although the livestock has presented with clinical signs. Therefore, a fast and accurate diagnosis is necessary to prevent the disease predominately in field isolates. This study aimed to investigate the sensitivity of molecular detection method using two different specific primers, namely, Internal Transcribed Spacer 1 (ITS-1) and Trypanosoma brucei repeat 1/2 (TBR-1/2) against T. evansi field isolates from Banten Province, Indonesia. Materials and Methods: The isolates of T. evansi used in this study were collected from Banten Province and cultured and preserved by the National Research Center for Veterinary Science, Indonesia. Eighteen experimental rats were divided into three equal groups, which were categorized as control, 1 × 101, and 1 × 104 infective doses. The isolates were injected into all experimental albino rats intraperitoneally. All samples were tested using conventional blood smear, card agglutination test (CATT), and polymerase chain reaction (PCR) method. Results: The results of the CATT examination in all treatments showed negative results. However, PCR results showed that two different primers, namely, ITS-1 and TBR-1/2 had been successfully detected T. evansi from infected experimental rats, proven by positive PCR band appeared in 480 base pairs (bp) and 164 bp, respectively. Conclusion: Based on the molecular diagnostic test using PCR method, TBR-1/2 primer is more sensitive to detect T. evansi compared to ITS-1 primer. The present finding provides preliminary data for studying the efficiency of different primers if practically applied as a standard diagnostic test for trypanosomiasis, especially in Indonesian livestock.

In vitro anti-trypanosomal effect of ivermectin on Trypanosoma evansi by targeting multiple metabolic pathways.

High cytotoxicity and increasing resistance reports of existing chemotherapeutic agents against T. evansi have raised the demand for novel, potent, and high therapeutic index molecules for the treatment of surra in animals. In this regard, repurposing approach of drug discovery has provided an opportunity to explore the therapeutic potential of existing drugs against new organism. With this objective, the macrocyclic lactone representative, ivermectin, has been investigated for the efficacy against T. evansi in the axenic culture medium. To elucidate the potential target of ivermectin in T. evansi, mRNA expression profile of 13 important drug target genes has been studied at 12, 24, and 48 h interval. In the in vitro growth inhibition assay, ivermectin inhibited T. evansi growth and multiplication significantly (p < 0.001) with IC50 values of 13.82 µM, indicating potent trypanocidal activity. Cytotoxicity assays on equine peripheral blood mononuclear cells (PBMCs) and Vero cell line showed that ivermectin affected the viability of cells with a half-maximal cytotoxic concentration (CC50) at 17.48 and 22.05 µM, respectively. Data generated showed there was significant down-regulation of hexokinase (p < 0.001), ESAG8 (p < 0.001), aurora kinase (p < 0.001), casein kinase 1 (p < 0.001), topoisomerase II (p < 0.001), calcium ATPase 1 (p < 0.001), ribonucleotide reductase I (p < 0.05), and ornithine decarboxylase (p < 0.01). The mRNA expression of oligopeptidase B remains refractory to the exposure of the ivermectin. The arginine kinase 1 and ribonucleotide reductase II showed up-regulation on treatment with ivermectin. The ivermectin was found to affect glycolytic pathways, ATP-dependent calcium ATPase, cellular kinases, and other pathway involved in proliferation and maintenance of internal homeostasis of T. evansi. These data imply that intervention with alternate strategies like nano-formulation, nano-carriers, and nano-delivery or identification of ivermectin homologs with low cytotoxicity and high bioavailability can be explored in the future as an alternate treatment for surra in animals.

Molecular Analysis of Trypanosome Infections in Algerian Camels.

PURPOSE: Surra 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. METHODS: Here 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/CONCLUSION: We 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.

Low Dose Gamma Irradiation of Trypanosoma evansi Parasites Identifies Molecular Changes That Occur to Repair Radiation Damage and Gene Transcripts That May Be Involved in Establishing Disease in Mice Post-Irradiation.

The protozoan parasite Trypanosoma evansi is responsible for causing surra in a variety of mammalian hosts and is spread by many vectors over a wide geographical area making it an ideal target for irradiation as a tool to study the initial events that occur during infection. Parasites irradiated at the representative doses 100Gy, 140Gy, and 200Gy were used to inoculate BALB/c mice revealing that parasites irradiated at 200Gy were unable to establish disease in all mice. Cytokine analysis of mice inoculated with 200Gy of irradiated parasites showed significantly lower levels of interleukins when compared to mice inoculated with non-irradiated and 100Gy irradiated parasites. Irradiation also differentially affected the abundance of gene transcripts in a dose-dependent trend measured at 6- and 20-hours post-irradiation with 234, 325, and 484 gene transcripts affected 6 hours post-irradiation for 100Gy-, 140Gy- and 200Gy-irradiated parasites, respectively. At 20 hours post-irradiation, 422, 381, and 457 gene transcripts were affected by irradiation at 100Gy, 140Gy, and 200Gy, respectively. A gene ontology (GO) term analysis was carried out for the three representative doses at 6 hours and 20 hours post-irradiation revealing different processes occurring at 20 hours when compared to 6 hours for 100Gy irradiation. The top ten most significant processes had a negative Z score. These processes fall in significance at 140Gy and even further at 200Gy, revealing that they were least likely to occur at 200Gy, and thus may have been responsible for infection in mice by 100Gy and 140Gy irradiated parasites. When looking at 100Gy irradiated parasites 20 hours post-irradiation processes with a positive Z score, we identified genes that were involved in multiple processes and compared their fold change values at 6 hours and 20 hours. We present these genes as possibly necessary for repair from irradiation damage at 6 hours and suggestive of being involved in the establishment of disease in mice at 20 hours post-irradiation. A potential strategy using this information to develop a whole parasite vaccine is also postulated.

Treatment of Trypanosoma evansi-Infected Mice With Eucalyptus camaldulensis Led to a Change in Brain Response and Spleen Immunomodulation.

Surra is a parasitic disease caused by the eukaryotic, unicellular hemoprotozoan, Trypanosoma evansi, which affects the development of animal production and is widespread among both domestic and wild animals. As such, in this research, we studied the antiparasitic activity and the ameliorative impact of Eucalyptus camaldulensis leaf extracts (ELE) against T. evansi-induced brain injury and spleen immune response in mice. As a result, we found that ELE decreased the amount of trypanosomes in the blood and improved the weight loss caused by infection. In addition, ELE reduced the parasite-induced brain and spleen histopathological damage. The parasite affected the levels of dopamine and serotonin, but after treatment with ELE, their concentrations significantly decreased to 154 ± 7 and 258 ± 11 µg/g, respectively. We clearly observed the antioxidant activity of ELE because of its ability to increase the induced change in the brain's total antioxidant capacity and the nitric oxide level. The histopathological changes in the spleen also improved after ELE application. Based on our results, we concluded that ELE possesses antitrypanosomal antioxidant and protective effects in the brains of mice infected with T. evansi. Additional phytochemical screening and molecular studies are required to understand the mechanism underlying the effect of ELE.

Gum-based nanocapsules comprising naphthoquinones enhance the apoptotic and trypanocidal activity against Trypanosoma evansi.

Nanoencapsulation is a promising approach to enhance the therapeutic potential of a drug. Herein, three selected naphthoquinone (NTQ) derivatives, based on the IC50 value against Trypanosoma evansi, were encapsulated using gum damar as biocompatible and biodegradable natural gum via nanoprecipitation method. Nanoformulation of NTQs (NNTQs) was less than 150 nm in size, was found to be stable and released the drug in a sustained manner. All the three NNTQs exhibited significant antitrypanosomal effect and morphological changes at approximately two to three times lesser drug concentrations. The nanoformulations exhibited enhanced production of reactive oxygen species (ROS) in the axenic culture of T. evansi and less cytotoxic effect on horse peripheral blood mononuclear cells relative to pure NTQs. As evidenced by flow cytometry, the NNTQs showed dose-dependent and time-dependent increased transition of live cells (AV-PI-) to early apoptotic cells (AV+PI-), late apoptotic cells (AV-PI+), and necrotic cells (AV+PI+) using annexin V/propidium iodide probe analysis. The results concluded that NNTQs induced more ROS, apoptosis and necrotic effects that exhibited more inhibitory effect on the growth of T. evansi with respect to respective NTQ by themselves.

Seroprevalence and immunological characterization of Trypanosoma evansi infection in livestock of four agro-climatic zones of Himachal Pradesh, India.

Trypanosoma evansi, a hemoflagellate protozoan parasite, causes wasting disease called surra in wide range of animals. Although the organism has been reported from various parts of India, data generated from organized epidemiological study is still in infancy in majority states of India. In the present study, livestock of Himachal Pradesh, India, was targeted for epidemiological investigation of T. evansi infections. A total of 440 equines and 444 cattle serum samples were collected from four agro-climatic zones. Furthermore, serum samples of 280 buffaloes from three different agro-climatic zones of Himachal Pradesh were also collected and evaluated for the presence of T. evansi infection by indirect ELISA. Data generated showed higher prevalence in buffalo (23.57%) followed by cattle (22.52%) and equines (1.82%). Disease was found to be more prevalent (P < 0.01) in cattle of lower altitude as compared to those of higher altitudes. No significant variation was seen in prevalence of disease on the basis of age and sex of the animals. Serum biochemical analysis revealed increased levels of BUN in T. evansi-infected equines. Levels of liver function enzymes such as ALT/GGT and AST were found to be significantly elevated (P < 0.01) in seropositive animals whereas glucose levels were significantly lower in surra-seropositive animals as compared to seronegative animals. Immunoblot analysis of whole cell lysate (WCL) antigen of T. evansi using surra-seropositive samples of equines showed immunodominant bands in the range of 100-25 kDa. Bovine-seropositive samples recognized polypeptide bands in the range of 85-32 kDa, including protein clusters of 52-55 and 48-46 kDa. Polypeptide cluster of 62-66 kDa was found common in seropositive samples of bovines and equines from all agro-climatic zones. T. evansi was found to be highly prevalent in livestock of Himachal Pradesh, and thus, there is dire need for designing of proper control strategies against surra.

Polymerase Spiral Reaction (PSR) as a novel rapid colorimetric isothermal point of care assay for detection of Trypanosoma evansi genomic DNA.

Polymerase spiral reaction (PSR) opens new avenues for specific diagnosis of pathogens known for cryptic infection at field level and its application is still unexplored in the field of parasitology. The present study aimed to explore and optimize colorimetric based PSR technique for the detection of Trypanosoma evansi in the blood of the host by targeting the 196bp Invariable Surface Glycoprotein (ISG) gene of Trypanosoma evansi. The specificity of the test was determined against Theileria equi, Theileria annulata, Babesia caballi, Burkholderia mallei and Equine herpes virus. The T. evansi DNA was extracted from purified parasites and serially diluted from 2.8ng to 2.8 × 10-8 pg. The detection limit of PSR was found to be as low as 2.8 × 10-6 pg of T. evansi DNA, which will aid in detection of Surra infection. The duration of reaction for determination of result of field sample is 1h and result can be read by naked eyes. In addition, PSR assay was also performed on DNA extracted from 28 field equine samples; out of which 1 was found positive by microscopy and ISG-196 targeted PCR assay and 2 were recorded positive by PSR assay. Data generated shows colorimetric PSR is convenient, rapid, sensitive and specific tool for diagnosis and monitoring of Surra infection in livestock at field level. Further, visual PSR assay has wide scope for application in government policies aimed at detection of early infection, sub-clinical cases, drug-efficacy studies, control and elimination of Surra organism from livestock animals.

The COMBAT project: controlling and progressively minimizing the burden of vector-borne animal trypanosomosis in Africa.

Vector-borne diseases affecting livestock have serious impacts in Africa. Trypanosomosis is caused by parasites transmitted by tsetse flies and other blood-sucking Diptera. The animal form of the disease is a scourge for African livestock keepers, is already present in Latin America and Asia, and has the potential to spread further. A human form of the disease also exists, known as human African trypanosomosis or sleeping sickness. Controlling and progressively minimizing the burden of animal trypanosomosis (COMBAT) is a four-year research and innovation project funded by the European Commission, whose ultimate goal is to reduce the burden of animal trypanosomosis (AT) in Africa. The project builds on the progressive control pathway (PCP), a risk-based, step-wise approach to disease reduction or elimination. COMBAT will strengthen AT control and prevention by improving basic knowledge of AT, developing innovative control tools, reinforcing surveillance, rationalizing control strategies, building capacity, and raising awareness. Knowledge gaps on disease epidemiology, vector ecology and competence, and biological aspects of trypanotolerant livestock will be addressed. Environmentally friendly vector control technologies and more effective and adapted diagnostic tools will be developed. Surveillance will be enhanced by developing information systems, strengthening reporting, and mapping and modelling disease risk in Africa and beyond. The socio-economic burden of AT will be assessed at a range of geographical scales. Guidelines for the PCP and harmonized national control strategies and roadmaps will be developed. Gender equality and ethics will be pivotal in all project activities. The COMBAT project benefits from the expertise of African and European research institutions, national veterinary authorities, and international organizations. The project consortium comprises 21 participants, including a geographically balanced representation from 13 African countries, and it will engage a larger number of AT-affected countries through regional initiatives.

Parasitological, serological, and molecular survey of trypanosomosis (Surra) in camels slaughtered in northwestern Nigeria.

Surra is a parasitic disease caused by Trypanosoma evansi and transmitted non-cyclically by biting flies. The disease significantly affects the health, productivity, and market value of camels thereby constituting a major constraint to food safety, security, and economy. This is the first study on the prevalence of surra in northwestern Nigeria, using a range of diagnostic tests along the parasitological-serological-molecular continuum hence, emphasizing it as a major enzootic risk for camels in Nigeria. In this cross-sectional study, 600 blood samples were collected from camels at major abattoirs in northwestern Nigeria and evaluated for the prevalence of T. evansi using parasitological (Giemsa staining), serological (CATT/T. evansi), and molecular (VSG-PCR and sequencing) methods. The overall prevalence of surra recorded in this study was 5.3%, 11.5%, and 22.5% using Giemsa-stained blood smears, CATT/T. evansi, and VSG-PCR respectively. However, higher prevalence rates at 6.0%, 13.7%, and 26.7% by Giemsa-stained blood smears, CATT/T. evansi, and VSG-PCR were recorded in Katsina State compared with results from Kano State. A significantly (p < 0.05) higher prevalence by VSG-PCR was observed when compared with both parasitological and serological methods used. Although age and body condition scores were associated (p < 0.05) with surra prevalence in sampled camels, no seasonal association (p > 0.05) was recorded. Sequencing of the VSG region of Trypanosoma spp. Further confirmed the presence of T. evansi as the aetiological agent of surra from the sampled camels. Findings from this study call for the implementation of adequate control measures aimed at reducing the impact of T. evansi infections on camel production in Nigeria.

Mining the pervasiveness of surra in different animal species of Northeastern states of India: Assam, Mizoram and Tripura.

Trypanosoma evansi is a flagellated, extracellular haemoprotozoan parasite infecting a wide range of mammalian hosts including dromedaries, cattle, equines and dogs cause disease surra. Carrier animals with sub-clinical infection cause significant monetary losses to livestock holders and therefore detection of infection status using molecular diagnostic techniques becomes important in order to control the disease. In the current study cattle, buffalo, goat, pig and dog samples from three northeastern states of India-Assam, Mizoram and Tripura were screened to determine the prevalence of surra. A total of 1702 samples including 795 from Assam, 678 from Mizoram and 229 from Tripura were screened by CATT/T. evansi test out of which 16.8%, 27.1% and 22.3% samples in respective states were found to have antibodies against T. evansi. DNA detection of T. evansi by PCR amplification targeting VSG gene revealed the molecular prevalence of surra in Assam, Mizoram and Tripura as 8.5%, 7.5% and 4.4% respectively. The analysis of amplified partial VSG sequences showed 99% similarity within an animal species whereas 86-94% similarity was observed among different species of animals revealing the homogeneity. The study established the prevalence of surra in different species of animals in the three northeastern states of India-Assam, Mizoram and Tripura and this study is the first report of T. evansi infection in pig and goat from India. SUPPLEMENTARY INFORMATION: The online version contains supplementary material available at 10.1007/s12639-021-01392-z.