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The aim of this study was to detect trypomastigote forms of Trypanosoma vivax, in blood smears, DNA of T. vivax and anti-T. vivax antibodies in samples from buffalos reared in the lowlands of Maranhão, Brazil. Blood samples were collected from 116 buffalos and 25 ectoparasite specimens. Blood smears were produced to diagnose forms compatible with Trypanosoma spp.; the indirect enzyme-linked immunosorbent assay (iELISA) and lateral-flow immunochromatography (Imunotest®) serological tests were used; and the polymerase chain reaction (PCR) was used to make molecular diagnoses. No forms compatible with Trypanosoma spp. were observed in blood smears. Among the 116 serum samples analyzed, 79.31% and 76.72% were positive in the ELISA and rapid tests, respectively. One sample was positive in the molecular test. Twenty-five lice of the species Haematopinus tuberculatus were collected. When subjected to PCR for detection of DNA of T. vivax, all of them were negative. The louse specimens were negative for T. vivax. There were no statistically significant differences (p < 0.05) in the presence of T. vivax in this region, in relation to the animals' age and sex. It can be concluded that these protozoa are circulating in the buffalo herd of the lowlands of Maranhão displaying crypitc parasitemias.

Stomoxyine biting flies play a pivotal role as mechanical vectors of Animal African Trypanosomosis (AAT), inducing painful bites and significant disturbances in cattle, thereby affecting productivity. This study delves into the dynamics of cypermethrin persistence on cattle, a key measure aimed at mitigating stomoxyine populations and the associated transmission of trypanosomes. Conducted within a cattle settlement in Ido, Ibadan, southwest Nigeria, data collection occurred biennially from 2016 to 2022. Cypermethrin application followed a restricted protocol triggered by high fly density. Stomoxyine flies were systematically trapped every three months over a five-day period, employing four Nzi traps per collection cycle. The flies were taxonomically categorised, and their relative abundance assessed. Additionally, engorged flies underwent ITS-PCR analysis to detect T. vivax presence in their mouthparts. The investigation unveiled a noteworthy decline in cypermethrin persistence from 10.7 to 4.9 days over the six-year span, significantly influencing stomoxyine population dynamics and T. vivax infection rates. Despite escalated cypermethrin utilisation, stomoxyine abundance exhibited stability, hinting at potential insecticidal resistance. Notably, cypermethrin persistence was at its highest during July-September, aligning with heightened rainfall and humidity conducive to stomoxyine larval development. The heightened probability of detecting T. vivax DNA in stomoxyine flies as cypermethrin persistence dwindled underscores the intricate interplay between reduced insecticide efficacy and heightened pathogen dissemination. This underscores the imperative for integrated, enhanced control strategies considering the prevailing T. vivax resistance to trypanocides and diminishing cypermethrin efficacy., (© 2024. The Author(s), under exclusive licence to Springer Nature B.V.)

The control of African trypanosomiasis (AT) in Eastern and Southern Africa, including Zambia, faces huge challenges due to the involvement of wild and domestic animal reservoirs. Free-roaming dogs in wildlife-populated and tsetse-infested villages of Zambia's Mambwe district are exposed to infectious tsetse bites. Consuming fresh raw game meat and bones further exacerbates their risk of contracting AT. We focus on the reservoir role of such dogs in maintaining and transmitting diverse species of trypanosomes that are infective to humans and livestock in Zambia's Mambwe district. A cohort of 162 dogs was enrolled for follow-up at 3 different time points from June to December 2018 in selected villages of Malama, Mnkhanya, and Nsefu chiefdoms of Mambwe district, eastern Zambia. Blood and serum were screened for AT by microscopy, GM6 ELISA, PCR (ITS1 and SRA), and Sanger sequencing. Out of the 162 dogs in the cohort, 40 were lost to follow-up and only 122 remained traceable at the end of the study. GM6 ELISA detected Trypanosoma antibodies in 121 dogs (74.7%) and ITS1-PCR detected DNA involving single and mixed infections of T. congolense, T. brucei, and suspected T. simiae or T. godfreyi in 115 dogs (70.9%). The human-infective T. b. rhodesiense was detected by SRA PCR in 67 dogs (41.4%), and some sequence data that support the findings of this study have been deposited in the GenBank under accession numbers OL961811, OL961812, and OL961813. Our study demonstrates that the Trypanosoma reservoir community in Zambia is wider than was thought and includes domesticated dogs. As dogs are active carriers of human and livestock-infective trypanosomes, they pose a risk of transmitting AT in endemic villages of Mambwe district as they are neglected and left untreated. To fully bring AT under control, countries such as Zambia where the role of animal reservoirs is important, should not limit their prevention and treatment efforts to livestock (especially cattle) but also include dogs that play an integral part in most rural communities., (© 2024. The Author(s).)

Trypanosoma vivax infections are endemic in Africa, where they provoke trypanosomosis against which some local taurine breeds are tolerant and are thus named trypanotolerant. In Latin America, T. vivax was imported in 1919, since when it has been responsible for periodic outbreaks of the disease. This study assessed whether a South American taurine breed resilient to several parasitic and infectious diseases (Curraleiro Pé-Duro-CPD) can meet trypanotolerant criteria (control parasite proliferation, prevent anemia, survive without treatment, and maintain productivity). Three groups were established, each consisting of six animals (Group 1: CPD-infected; Group 2: Holstein/Gyr-infected; Group 3: Holstein/Gyr-uninfected, negative control). Groups 1 and 2 were infected with T. vivax on Day 0 and evaluated until day 532. Throughout the experimental period, parasitological (Woo and Brener), molecular (cPCR), serological (enzyme-linked immunosorbent assay - ELISA, indirect fluorescent antibody test - IFAT, immunochromatographic assay - IA), and clinical (hemogram, fever, weight loss) aspects were evaluated. During the acute phase of the disease, T. vivax was initially detected in Holstein/Gyr. Notably, the CPD animals restored their packed cell volume (PCV) values to the normal range 74 days after inoculations. In the chronic phase, two of the six CPD animals were positive by cPCR until D + 522 following immunosuppression with dexamethasone. Regarding serological aspects, the two CPD animals had positive tests until D + 532. The absence of T. vivax in blood during the chronic phase did not correspond to "self-cure". Holstein/Gyr animals exhibited fever on more evaluation days than CPD animals. Both breeds experienced weight loss, with Holstein/Gyr animals losing significantly more weight. On D + 25, the Holstein/Gyr group required treatment. During the 532 days, none of the CPD animals required treatment, even after being sensitized with dexamethasone. Animals from Group 3 tested negative for T. vivax throughout the experiment. This study demonstrated that CPD cattle fulfill the mentioned trypanotolerant criteria., Competing Interests: Declaration of competing interest The authors declare the following financial interests/personal relationships which may be considered as potential competing interests., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study evaluated the reproductive, productive and financial consequences of chronic Trypanosoma vivax infection in a dairy cattle herd located in a region without the cyclic vector during two years. Animals were categorized as either positive (chronically infected) or negative for T. vivax antibodies using a commercial rapid test. Additionally, serum samples from cows were analyzed for the presence of anti-Neospora caninum antibodies. Pregnancy diagnoses were performed through rectal palpation and ultrasonography after 30, 60 and every 21 days until the 144th day of pregnancy. If an abortion occurred in the final trimester, serology and cPCR were performed on calves for T. vivax and N. caninum. The breeding period, calving interval and pregnancy losses were recorded. The milk production of each animal during the 305 days of lactation was measured, and the annual financial impact of milk production was calculated using a revenue minus feed cost (RMFC) indicator. Out of 177 cows, 71.75 % were chronically infected, and 13.50 % were T. vivax-negative. No correlation (p = 0.8854) of co-infection between T. vivax and N. caninum was observed. Negative cows required fewer (p≤0.05) artificial inseminations than chronically infected ones. T. vivax was not significantly associated (p = 0.7893) with pregnancy loss up to 81 days of pregnancy. Cows chronically infected by T. vivax had 4-fold greater chance (p = 0.0280) of experiencing pregnancy loss between 82 and 144 days of gestation. Eighteen cows aborted, two were positive for T. vivax antibodies, and one for N. caninum antibodies. The calves were negative for T. vivax and N. caninum. Chronically infected cows and negative cows for T. vivax that experienced pregnancy loss (82-144 days of pregnancy) had a longer (p≤0.05) breeding period to become pregnant, and consequently a longer calving interval compared to cows that maintained pregnancy. The difference (p≤0.05) in milk production was evident when pregnancy loss occurred between 82 and 144 days of gestation in cows chronically infected by T. vivax. The RMFC indicated a negative impact of 38.2 % on the farm's annual milk revenue due to the presence of chronically infected cows., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2024 Elsevier B.V. All rights reserved.)

This study reports assessment of the sensitivity of diagnostic techniques to detect T. vivax in experimentally infected cattle. Additionally, it describes T. vivax extravascular parasitism during the acute and chronic phases of trypanosomosis and congenital transmission. The T. vivax diagnosis was compared using blood samples collected from the jugular, coccygeal and ear tip veins. For this study, 13 males and two females were infected with ≈ 1 × 10 6 viable T. vivax trypomastigotes (D0). One animal was kept as a negative control during the entire study. The 13 infected males were euthanized between 14 and 749 days post-infection (DPI). After confirming the cyclicity of both females (9 months of age), they were naturally mated with a bull. One female was euthanized at 840 DPI, and the other at 924 DPI. The two calves, one from each female, were euthanized at six months of age (924 DPI), and the negative control at 924 DPI. During this period, T. vivax in blood was assessed using direct methods (Woo test, cPCR, microscopic examination of fresh wet blood films and parasite quantification - Brener method), and serological methods (IFAT, ELISA, and IA). Tissue samples were collected from the liver, spleen, brain, cerebellum, heart, testicles, epididymis, kidneys, eyeballs, pre-scapular lymph nodes, ear tips, mammary glands, uterus, and ovaries. The protozoan DNA was examined using LAMP. There was no difference in the detection of T. vivax using the Woo test and Brener method among the jugular, coccygeal, and ear tip veins. The sensitivity of the detection methods varied depending on the disease phase. Direct methods (Woo test, Brener method, and cPCR) demonstrated higher sensitivity during the acute phase, while serological methods (IFAT, ELISA, and IA) were more sensitive during the chronic phase. Anti-T. vivax antibodies were detected up to 924 DPI. Tissue evaluation using LAMP demonstrated the presence of T. vivax DNA and associated histopathological changes up to 840 or 924 DPI. Only in mammary glands and ovaries was no DNA detected. The most frequently observed histopathological alteration was lymphohistioplasmocytic inflammatory infiltrate. No transplacental transmission of T. vivax was observed., Competing Interests: Declaration of competing interest The authors have no competing interests to declare that are relevant to the content of this article., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Bovine trypanosomosis, caused by Trypanosoma vivax, currently affects cattle and has a significant economic impact in sub-Saharan Africa and South America. The development of new diagnostic antigens is essential to improve and refine existing methods. Our study evaluated the efficacy of two recombinant antigens in detecting specific antibodies in cattle. These antigens are derivatives of an invariant surface glycoprotein (ISG) from T. vivax. A fraction of a previously described antigen (TvY486&#95;0045500), designated TvISGAf, from an African strain was evaluated, and a new ISG antigen from an American isolate, TvISGAm, was identified. The two antigens were expressed as fusion proteins in Escherichia coli: TvISGAf was fused to the MBP-His-tag, and TvISGAm was obtained as a His-tag fused protein. An ELISA evaluation was conducted using these antigens on 149 positive and 63 negative bovine samples. The diagnostic performance was enhanced by the use of a combination of both antigens (referred to as TvISG-based ELISA), achieving a sensitivity of 89.6% and specificity of 93.8%. Following the validation of the TvISG-based ELISA, the seroprevalence of T. vivax infection in 892 field samples from cattle in the central region of Argentina was determined. The mean seroprevalence of T. vivax was 53%, with variation ranging from 21% to 69% among the six departments studied. These results support the use of the TvISG ELISA as a valuable serological tool for the detection and monitoring of T. vivax infection in cattle. Furthermore, we report for the first time the seroprevalence of T. vivax in Argentina, which highlights the widespread endemic nature of the disease in the region. In order to effectively manage the increasing spread of T. vivax in the vast livestock production areas of South America, it is essential to implement consistent surveillance programs and to adopt preventive strategies., Competing Interests: I have read the journal’s policy and the authors of this manuscript have the following competing interests:We have filed a patent on the diagnostic antigens described in this paper., (Copyright: © 2024 Bontempi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Animal African trypanosomosis (AAT) is an important global disease of livestock that causes economic losses of up to 4.5 billion US dollars per year. Thus, eliminating AAT in endemic countries will improve agricultural productivity and economic growth. To prevent AAT, vector control and the development of prophylactic drugs are crucial. Ascofuranone (AF) is a bioactive fungal compound with proven in vitro trypanocidal potency and in vivo treatment efficacy. However, the complex stereoselective synthesis of AF has prevented its cost-effective industrial production. Recently, a genetically modified strain of Acremonium egyptiacum fungus that produces a high yield of AF was developed. Therefore, we hypothesized that the oral administration of the AF-producing fungus itself may be effective against AAT. Hence, this study aimed to evaluate the prophylactic activity of orally administered dry-heat-sterilized A. egyptiacum against Trypanosoma congolense IL3000 infection using a mouse model. The survival rate was significantly prolonged (p = 0.009), and parasitemia was suppressed in all AF-fungus-treated groups (Group 1-9) compared with that in the untreated control group (Group 10). Hence, the trypanocidal activity of AF was retained after dry-heat-sterilization of the AF-producing fungus and that its oral administration effectively prevented AAT. Since AAT is endemic to rural areas with underdeveloped veterinary infrastructure, dry-heat-sterilized A. egyptiacum would be the most cost-effective potential treatment for AAT., Competing Interests: Declaration of competing interest The authors declare no competing interests in association with this study., (Copyright © 2024 Elsevier B.V. All rights reserved.)

Background: Animal African trypanosomiasis, which is caused by different species of African trypanosomes, is a deadly disease in livestock. Although African trypanosomes are often described as blood-borne parasites, there have been recent reappraisals of the ability of these parasites to reside in a wide range of tissues. However, the majority of those studies were conducted on non-natural hosts infected with only one species of trypanosome, and it is unclear whether a similar phenomenon occurs during natural animal infections, where multiple species of these parasites may be present., Methods: The infective trypanosome species in the blood and other tissues (adipose and skin) of a natural host (cows, goats and sheep) were determined using a polymerase chain reaction-based diagnostic., Results: The animals were found to harbour multiple species of trypanosomes. Different patterns of distribution were observed within the host tissues; for instance, in some animals, the blood was positive for the DNA of one species of trypanosome and the skin and adipose were positive for the DNA of another species. Moreover, the rate of detection of trypanosome DNA was highest for skin adipose and lowest for the blood., Conclusions: The findings reported here emphasise the complexity of trypanosome infections in a natural setting, and may indicate different tissue tropisms between the different parasite species. The results also highlight the need to include adipose and skin tissues in future diagnostic and treatment strategies., (© 2024. The Author(s).)

Animal African trypanosomiasis, also known as nagana, is caused by Trypanosoma species, which cause significant clinical diseases and lead to losses in animal production. We carried out a cross-sectional survey to investigate the composition of vectors and parasite diversity in two districts in the eastern region of Ghana where pigs and cattle were exposed to tsetse bites. We performed cytochrome c oxidase subunit 1 polymerase chain reaction (PCR) to identify tsetse species and internal transcribed spacer 1 PCR to identify Trypanosoma species. Also, we investigated the source of tsetse blood meal based on mitochondrial cytochrome b gene sequence analysis. A total of 229 tsetse, 65 pigs, and 20 cattle were investigated for trypanosomes. An overall vector density of 4.3 tsetse/trap/day was observed. A trypanosome prevalence of 58.9% (95% CI = 52.5-65.1%), 46.2% (95% CI = 34.6-58.1%), and 0.0% (95% CI = 0.0-16.1%) in tsetse, pigs, and cattle, respectively, was detected. Trypanosoma congolense was predominant, with a prevalence of 33.3% (95% CI = 73.3-86.5%) in tsetse. There was evidence of multiple infections in tsetse and pigs. Approximately 39% of the tsetse were positive for multiple infections of T. congolense and Trypanosoma simiae. Parasite prevalence in pigs across the communities was high, with significant differences associated between locations (χ2 = 28.06, 95% CI = 0.05-0.81, P = 0.0009). Tsetse blood meal analysis revealed feeding on domestic Sus scrofa domesticus (pigs) and Phacochoerus africanus (warthogs). Infective tsetse may transmit trypanosomes to livestock and humans in the communities studied.

African animal trypanosomosis is a parasitic disease that causes significant economic losses in livestock due to anaemia, loss of condition, emaciation, and mortality. It is a key impediment to increased cattle output and productivity in Ethiopia. Cross-sectional entomological and parasitological studies were performed in the Gambella Region state of southwestern Ethiopia to estimate the prevalence of bovine trypanosomosis, apparent fly density, and potential risk factors. Blood samples were taken from 546 cattle for the parasitological study and analyzed using the buffy coat technique and stained with Giemsa. A total of 189 biconical (89) and NGU (100) traps were deployed in the specified districts for the entomological survey. The overall prevalence of trypanosomosis at the animal level was 5.5% (95% CI: 3.86-7.75). Trypanosoma vivax (50.0%), T. congolense (30.0%), T. brucei (20.0%), and no mixed trypanosome species were found. The prevalence of trypanosomosis was significantly (p < 0.05) affected by altitude, body score conditions, age, mean packed cell volume (PCV), and peasant associations, while sex and coat color had no significant effect. According to the entomological survey results, a total of 2303 flies were captured and identified as tsetse (Glossina pallidipes (5.3%)) and G. fuscipes fuscipes (3.3%) and other biting flies (Tabanus (60.1%) and Stomoxys (31.3%)). In the current study, the overall apparent density was 4.1 flies/trap/day. This study shows that trypanosomosis remains a significant cattle disease in the Gambella regional state even during the dry season. Thus, the findings support the necessity to improve vector and parasite control measures in the area., Competing Interests: Declaration of competing interest The authors have no conflicts of interest to declare. The research have no affiliations with or involvement in any organization or entity with any financial interest (such as honoraria; educational grants; participation in speakers' bureaus; membership, employment, consultancies, stock ownership, or other equity interest; and expert testimony or patent-licensing arrangements), or non-financial interest (such as personal or professional relationships, affiliations, knowledge or beliefs) in the subject matter or materials discussed in this manuscript., (Copyright © 2024 Elsevier Ltd. All rights reserved.)

Animal African trypanosomosis (AAT) is a disease caused by Trypanosoma brucei brucei, T. vivax, T. evansi and T. congolense which are mainly transmitted by tsetse flies (maybe the family/genus scientific name for the tsetse flies here?). Synthetic trypanocidal drugs are used to control AAT but have reduced efficacy due to emergence of drug resistant trypanosomes. Therefore, there is a need for the continued development of new safe and effective drugs. The aim of this study was to evaluate the in vitro anti-trypanosomal activity of novel nitrofurantoin compounds against trypanosomes (Trypanosoma brucei brucei, T. evansi and T. congolense) causing AAT. This study assessed previously synthesized nineteen nitrofurantoin-triazole (NFT-TZ) hybrids against animal trypanosomes and evaluated their cytotoxicity using Madin-Darby bovine kidney cells. The n-alkyl sub-series hybrids, 8 (IC 50 0.09 ± 0.02 μM; SI 686.45) and 9 (IC 50 0.07 ± 0.04 μM; SI 849.31) had the highest anti-trypanosomal activity against T. b. brucei. On the contrary, the nonyl 6 (IC 50 0.12 ± 0.06 μM; SI 504.57) and nitrobenzyl 18 (IC 50 0.11 ± 0.03 μM; SI 211.07) displayed the highest trypanocidal activity against T. evansi. The nonyl hybrid 6 (IC 50 0.02 ± 0.01 μM; SI 6328.76) was also detected alongside the undecyl 8 (IC 50 0.02 ± 0.01 μM; SI 3454.36) and 3-bromobenzyl 19 (IC 50 0.02 ± 0.01 μM; SI 2360.41) as the most potent hybrids against T. congolense. These hybrids had weak toxicity effects on the mammalian cells and highly selective submicromolar antiparasitic action efficacy directed towards the trypanosomes, hence they can be regarded as potential trypanocidal leads for further in vivo investigation., Competing Interests: Declaration of competing interest None., (Copyright © 2024 The Authors. Published by Elsevier Inc. All rights reserved.)

Purpose: African Animal Trypanosomosis (AAT) caused by Trypanosoma congolense is a parasitic disease affecting the livestock industry in sub-Saharan Africa and usually results in severe anemia, organ damage, and ultimately the death of the infected host. The present study was designed to investigate the possible chemotherapeutic effect of eugenol on T. congolense infections and its inhibitory effect on the trans-sialidase (TconTS) gene expression., Methods: Animals were infected with T. congolense and treated with 15 and 30 mg/kg body weight (BW) of eugenol for ten (10) days., Results: The eugenol (15 mg/kg BW) significantly (P < 0.05) reduced the T. congolense proliferation, increased animal survival, and reduced serum urea level. However, both dosages of eugenol significantly (P < 0.05) ameliorated T. congolense-induced anemia, renal hypertrophy, splenomegaly, and reduced total damage score in the liver and kidney of infected animals. In addition, the compound significantly (P < 0.05) downregulated the expression levels of TconTS1, TconTS2, TconTS3, and TconTS4 but the effect was more pronounced (sevenfold reduction) on TconTS1., Conclusions: The oral administration of eugenol suppressed T. congolense proliferation and prevented some major pathologies associated with trypanosomiasis infection. The reversal of renal hypertrophy and splenomegaly by the compound in addition to the reduction in the expression level of the TconTS gene variants could explain the observed anemia ameliorative potential of the compound., (© 2023. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Animal African trypanosomiasis (AAT) is a significant food security and economic burden in sub-Saharan Africa. Current AAT empirical and immunodiagnostic surveillance tools suffer from poor sensitivity and specificity, with blood sampling requiring animal restraint and trained personnel. Faecal sampling could increase sampling accessibility, scale, and species range. Therefore, this study assessed feasibility of detecting Trypanosoma DNA in the faeces of experimentally-infected cattle. Holstein-Friesian calves were inoculated with Trypanosoma brucei brucei AnTat 1.1 (n = 5) or T. congolense Savannah IL3000 (n = 6) in separate studies. Faecal and blood samples were collected concurrently over 10 weeks and screened using species-specific PCR and qPCR assays. T. brucei DNA was detected in 85% of post-inoculation (PI) faecal samples (n = 114/134) by qPCR and 50% by PCR between 4 and 66 days PI. However, T. congolense DNA was detected in just 3.4% (n = 5/145) of PI faecal samples by qPCR, and none by PCR. These results confirm the ability to consistently detect T. brucei DNA, but not T. congolense DNA, in infected cattle faeces. This disparity may derive from the differences in Trypanosoma species tissue distribution and/or extravasation. Therefore, whilst faeces are a promising substrate to screen for T. brucei infection, blood sampling is required to detect T. congolense in cattle., (© 2024. The Author(s).)

Trypanosomosis is a disease complex which affects both humans and animals in sub-Saharan Africa, transmitted by the tsetse fly and distributed within the tsetse belt of Africa. But some trypanosome species, for example, Trypanosoma brucei evansi, T. vivax, T. theileri and T. b. equiperdum are endemic outside the tsetse belt of Africa transmitted by biting flies, for example, Tabanus and Stomoxys, or venereal transmission, respectively. Trypanocidal drugs remain the principal method of animal trypanosomosis control in most African countries. However, there is a growing concern that their effectiveness may be severely curtailed by widespread drug resistance. A minimum number of six male cattle calves were recruited for the study. They were randomly grouped into two (T. vivax and T. congolense groups) of three calves each. One calf per group served as a control while two calves were treatment group. They were inoculated with 105 cells/mL parasites in phosphate buffered solution (PBS) in 2 mL. When parasitaemia reached 1 × 107.8 cells/mL trypanosomes per mL in calves, treatment was instituted with 20 mL (25 mg/kg in 100 kg calf) ascofuranone (AF) for treatment calves, while the control ones were administered a placebo (20 mL PBS) intramuscularly. This study revealed that T. vivax was successfully cleared by AF but the T. congolense group was not cleared effectively.Contribution: There is an urgent need to develop new drugs which this study sought to address. It is suggested that the AF compound can be developed further to be a sanative drug for T. vivax in non-tsetse infested areas like South Americas.

Background: Animal trypanosomiasis is a major livestock problem due to its socioeconomic impacts in tropical countries. Currently used trypanocides are toxic, expensive, and the parasites have developed resistance to the existing drugs, which calls for an urgent need of new effective and safe chemotherapeutic agents from alternative sources such as medicinal plants. In Ethiopian traditional medicine fresh leaves of Ranunculus multifidus Forsk, are used for the treatment of animal trypanosomiasis. The present study aimed to evaluate the antitrypanosomal activity of the fresh leaves of R. multifidus and its major compound anemonin against Trypanosoma congolense field isolate., Methods: Fresh leaves of R. multifidus were extracted by maceration with 80% methanol and hydro-distillation to obtain the corresponding extracts. Anemonin was isolated from the hydro-distilled extract by preparative TLC. For the in vitro assay, 0.1, 0.4, 2 and 4 mg/ml of the test substances were incubated with parasites and cessation or drop in motility of the parasites was monitored for a total duration of 1 h. In the in vivo assay, the test substances were administered intraperitoneally daily for 7 days to mice infected with Trypanosoma congolense. Diminazene aceturate and 1% dimethylsulfoxide (DMSO) were used as positive and negative controls, respectively., Results: Both extracts showed antitrypanosomal activity although the hydro-distilled extract demonstrated superior activity compared to the hydroalcoholic extract. At a concentration of 4 mg/ml, the hydro-distilled extract drastically reduced motility of trypanosomes within 20 min. Similarly, anemonin at the same concentration completely immobilized trypanosomes within 5 min of incubation, while diminazene aceturate (28.00 mg/kg/day) immobilized the parasites within 10 min. In the in vivo antitrypanosomal assay, anemonin eliminates parasites at all the tested doses (8.75, 17.00 and 35.00 mg/kg/day) and prevented relapse, while in diminazene aceturate-treated mice the parasites reappeared on days 12 to 14., Conclusions: The current study demonstrated that the fresh leaves of R. multifidus possess genuine antitrypanosomal activity supporting the use of the plant for the treatment of animal trypanosomiasis in traditional medicine. Furthermore, anemonin appears to be responsible for the activity suggesting its potential as a scaffold for the development of safe and cost effective antitrypanosomal agent., (© 2024. The Author(s).)

Background: In tropical Africa animal trypanosomiasis is a disease that has severe impacts on the health and productivity of livestock in tsetse fly-infested regions. Trypanosoma congolense savannah (TCS) is one of the main causative agents and is widely distributed across the sub-Saharan tsetse belt. Population genetics analysis has shown that TCS is genetically heterogeneous and there is evidence for genetic exchange, but to date Trypanosoma brucei is the only tsetse-transmitted trypanosome with experimentally proven capability to undergo sexual reproduction, with meiosis and production of haploid gametes. In T. brucei sex occurs in the fly salivary glands, so by analogy, sex in TCS should occur in the proboscis, where the corresponding portion of the developmental cycle takes place. Here we test this prediction using genetically modified red and green fluorescent clones of TCS., Methods: Three fly-transmissible strains of TCS were transfected with genes for red or green fluorescent protein, linked to a gene for resistance to the antibiotic hygromycin, and experimental crosses were set up by co-transmitting red and green fluorescent lines in different combinations via tsetse flies, Glossina pallidipes. To test whether sex occurred in vitro, co-cultures of attached epimastigotes of one red and one green fluorescent TCS strain were set up and sampled at intervals for 28 days., Results: All interclonal crosses of genetically modified trypanosomes produced hybrids containing both red and green fluorescent proteins, but yellow fluorescent hybrids were only present among trypanosomes from the fly proboscis, not from the midgut or proventriculus. It was not possible to identify the precise life cycle stage that undergoes mating, but it is probably attached epimastigotes in the food canal of the proboscis. Yellow hybrids were seen as early as 14 days post-infection. One intraclonal cross in tsetse and in vitro co-cultures of epimastigotes also produced yellow hybrids in small numbers. The hybrid nature of the yellow fluorescent trypanosomes observed was not confirmed by genetic analysis., Conclusions: Despite absence of genetic characterisation of hybrid trypanosomes, the fact that these were produced only in the proboscis and in several independent crosses suggests that they are products of mating rather than cell fusion. The three-way strain compatibility observed is similar to that demonstrated previously for T. brucei, indicating that a simple two mating type system does not apply for either trypanosome species., (© 2024. The Author(s).)

African animal trypanosomosis (AAT) was one of the main disease-related constraints to the development of intensive livestock production systems in the Niayes region of Senegal, a 30 km wide strip of land along the coast between Dakar and Saint-Louis. To overcome this constraint, the Government of Senegal initiated an area-wide integrated pest management programme combining chemical control tactics with the sterile insect technique to eradicate a population of the tsetse fly Glossina palpalis gambiensis Vanderplank, 1949 (Diptera, Glossinidae) in this area. The project was implemented following a phased conditional approach, and the target area was divided into three blocks treated sequentially. This study aims to assess the temporal dynamics of the prevalence of Trypanosoma spp. during the implementation of this programme. Between 2009 and 2022, 4,359 blood samples were collected from cattle and screened for trypanosomes using both the buffy coat and ELISA techniques, and PCR tests since 2020. The seroprevalence decreased from 18.9% (95%CI: 11.2-26.5) in 2009 to 0% in 2017-2022 in block 1, and from 92.9% (95%CI: 88.2-97) in 2010 to 0% in 2021 in block 2. The parasitological and serological data confirm the entomological monitoring results, i.e., that there is a high probability that the population of G. p. gambiensis has been eradicated from the Niayes and that the transmission of AAT has been interrupted in the treated area. These results indicate the effectiveness of the adopted approach and show that AAT can be sustainably removed through the creation of a zone free of G. p. gambiensis., (© M.T. Seck et al., published by EDP Sciences, 2024.)

African trypanosomiasis is a significant vector-borne disease of humans and animals in the tsetse fly belt of Africa, particularly affecting production animals such as cattle, and thus, hindering food security. Trypanosoma congolense (T. congolense), the causative agent of nagana, is livestock's most virulent trypanosome species. There is currently no vaccine against trypanosomiasis; its treatment relies solely on chemotherapy. However, pathogenic resistance has been established against trypanocidal agents in clinical use. This underscores the need to develop new therapeutics to curb trypanosomiasis. Many nitroheterocyclic drugs or compounds, including nitrofurantoin, possess antiparasitic activities in addition to their clinical use as antibiotics. The current study evaluated the in vitro trypanocidal potency and in vivo treatment efficacy of previously synthesized antileishmanial active oligomeric ethylene glycol derivatives of nitrofurantoin. The trypanocidal potency of analogues 2a-o varied among the trypanosome species; however, T. congolense strain IL3000 was more susceptible to these drug candidates than the other human and animal trypanosomes. The arylated analogues 2k (IC 50  0.04 µM; SI >6365) and 2l (IC 50  0.06 µM; SI 4133) featuring 4-chlorophenoxy and 4-nitrophenoxy moieties, respectively, were revealed as the most promising antitrypanosomal agents of all analogues against T. congolense strain IL3000 trypomastigotes with nanomolar activities. In a preliminary in vivo study involving T. congolense strain IL3000 infected BALB/c mice, the oral administration of 100 mg/kg/day of 2k caused prolonged survival up to 18 days post-infection relative to the infected but untreated control mice which survived 9 days post-infection. However, no cure was achieved due to its poor solubility in the in vivo testing medium, assumably leading to low oral bioavailability. These results confirm the importance of the physicochemical properties lipophilicity and water solubility in attaining not only in vitro trypanocidal potency but also in vivo treatment efficacy. Future work will focus on the chemical optimization of 2k through the investigation of analogues containing solubilizing groups at certain positions on the core structure to improve solubility in the in vivo testing medium which, in the current investigation, is the biggest stumbling block in successfully treating either animal or human Trypanosoma infections., Competing Interests: Declaration of Competing Interest The authors have no relevant financial or non-financial interests to disclose., (Copyright © 2023. Published by Elsevier B.V.)

Tsetse flies (Glossina spp.) are major vectors of African trypanosomes, causing either Human or Animal African Trypanosomiasis (HAT or AAT). Several approaches have been developed to control the disease, among which is the anti-vector Sterile Insect Technique. Another approach to anti-vector strategies could consist of controlling the fly's vector competence through hitherto unidentified regulatory factors (genes, proteins, biological pathways, etc.). The present work aims to evaluate the protein abundance in the midgut of wild tsetse flies (Glossina palpalis palpalis) naturally infected by Trypanosoma congolense s.l. Infected and non-infected flies were sampled in two HAT/AAT foci in Southern Cameroon. After dissection, the proteomes from the guts of parasite-infected flies were compared to that of uninfected flies to identify quantitative and/or qualitative changes associated with infection. Among the proteins with increased abundance were fructose-1,6-biphosphatase, membrane trafficking proteins, death proteins (or apoptosis proteins) and SERPINs (inhibitor of serine proteases, enzymes considered as trypanosome virulence factors) that displayed the highest increased abundance. The present study, together with previous proteomic and transcriptomic studies on the secretome of trypanosomes from tsetse fly gut extracts, provides data to be explored in further investigations on, for example, mammal host immunisation or on fly vector competence modification via para-transgenic approaches., (© 2023 The Authors. Medical and Veterinary Entomology published by John Wiley & Sons Ltd on behalf of Royal Entomological Society.)

African animal trypanosomiasis (AAT) is one of the major constraints to animal health and production in sub-Saharan Africa. To inform AAT control in Uganda and help advance along the progressive control pathway (PCP), we characterized AAT prevalence among eight host species in Uganda and explored factors that influence the prevalence variation between studies. We retrieved AAT prevalence publications (n = 2232) for Uganda (1980-2022) from five life sciences databases, focusing on studies specifying AAT detection methods, sample size, and the number of trypanosome-positive animals. Following PRISMA guidelines, we included 56 publications, and evaluated publication bias by the Luis Furuya-Kanamori (LFK) index. National AAT prevalence under DNA diagnostic methods for cattle, sheep and goats was 22.15%, 8.51% and 13.88%, respectively. Under DNA diagnostic methods, T. vivax was the most common Trypanosoma sp. in cattle (6.15%, 95% CI: 2.91-10.45) while T. brucei was most common among small ruminants (goats: 8.78%, 95% CI: 1.90-19.88, and sheep: 8.23%, 95% CI: 4.74-12.50, respectively). Northern and Eastern regions accounted for the highest AAT prevalence. Despite the limitations of this study (i.e., quality of reviewed studies, underrepresentation of districts/regions), we provide insights that could be used for better control of AAT in Uganda and identify knowledge gaps that need to be addressed to support the progressive control of AAT at country level and other regional endemic countries with similar AAT eco-epidemiology., (© 2023. The Author(s).)

Animal African trypanosomosis is an important vector-borne disease of livestock in sub-Saharan Africa. Pigs seem relatively tolerant to trypanosome infection and could act as a reservoir of trypanosomes affecting animals and humans. Our ability to reliably detect trypanosome infection in pigs depends on the performance of diagnostic tools, which is not well known. In pigs experimentally infected with Trypanosoma brucei brucei, we evaluated the performance of parasitological Buffy Coat Technique (BCT), two molecular (TBR and 5.8S PCR) and four serological tests (CATT, HAT Sero-K-Set rapid diagnostic test-RDT, indirect ELISA, immune trypanolysis). Most diagnostic tests showed high specificity, estimated at 100% (95% CI = 74-100%) with the exception of CATT and RDT whose specificity varied between 100% (95% CI = 74-100%) to 50% (95% CI = 7-93%) during the experiment. The sensitivity of each test fluctuated over the course of the infection. The percentage of positive BCT over the infection (30%) was lower than of positive PCR (56% and 62%, depending on primers). Among the serological tests, the percentage of positive tests was 97%, 96%, 86% and 84% for RDT, ELISA, immune trypanolysis and CATT, respectively. Fair agreement was observed between both molecular tests (κ = 0.36). Among the serological tests, the agreement between the ELISA and the RDT was substantial (κ = 0.65). Our results on the T.b. brucei infection model suggest that serological techniques are efficient in detecting the chronic phase of infection, PCR is able to detect positive samples several months after parasites inoculation while BCT becomes negative. BCT examination and RDT are useful to get a quick information in the field, and BCT can be used for treatment decision. ELISA appears most suited for epidemiological studies. The selection of diagnostic tests for trypanosomosis in pigs depends on the context, the objectives and the available resources., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Ilboudo et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

The "Lysis and Concentration Technique" (LCTe) involves lysing red blood cells and concentrating parasites to increase the chances of visualization in low parasitemia and in scenarios of evaluators with less knowledge. The lysis of red blood cells reduced the time of diagnosis by 21 s, showing that the effect produced by the treatment is comparable to the effect of the experience in parasitological examination. In addition, the concentration of parasites was 39.18% higher for slides with high parasitemia and 131.03% for slides with low parasitemia in relation to the standard slide. LCTe proved to be inexpensive, with a total cost of approximately US$0.07 per slide made, which allows it to be easily implemented in most laboratories., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier B.V. All rights reserved.)

Despite considerable data generated on livestock trypanosomoses in tsetse-infested areas, little attention was paid for animal African trypanosomosis (AAT) in sleeping sickness foci. This study aimed to fill this gap by determining the diversity and prevalence of trypanosome species in animals from three Chadian human African trypanosomosis (HAT) foci. Blood samples were collected from 443 goats, 339 sheep, 228 dogs and 98 pigs of the Mandoul, Maro and Moissala HAT foci in the south of Chad. Capillary tube centrifugation (CTC) and specific primers were used to search trypanosomes. The prevalence of trypanosome infections was 6.3% for CTC and 22.7% for PCR. Trypanosomes of the sub-genus Trypanozoon had the highest prevalence (16.6%) while T. congolense savannah (1.9%) was least prevalent. Significant differences were recorded between the prevalence of trypanosome species (χ 2  = 8.34; p = 0.04) and HAT foci (χ 2  = 24.86; p ≤0.0001). Maro had the highest prevalence (32.7%) and Mandoul the lowest (17.4%). Significant differences were also recorded for T. congolense forest (χ 2  = 45.106; p < 0.0001) and all T. congolense (χ 2  = 34.992; p < 0.0001). Goats had the highest prevalence (26.9%) and sheep the lowest one (18.6%). Between animals, significant differences were recorded for trypanosomes of the sub-genus Trypanozoon (χ 2  = 9.443; p = 0.024), T. congolense forest (χ 2  = 10.476; p = 0.015) and all T. congolense (χ 2  = 12.152; p = 0.007). Of the 251 animals carrying trypanosome infections, 88.8% had single infections while 11.2% had more than one trypanosome species. The overall prevalence of single and mixed trypanosome infections were respectively 20.1% and 2.6% in animal taxa of all foci. This study highlighted a diversity of trypanosomes in animal taxa of all HAT foci. It showed that AAT constitutes a threat for animal health and animal breeding in Chadian HAT foci. In these tsetse infested areas, reaching the elimination of AAT requires the designing and the implementation of control measures against trypanosome infections., Competing Interests: Declaration of Competing Interest The authors declare that they have no competing interests., (Copyright © 2023 Elsevier B.V. All rights reserved.)

African Animal Trypanosomosis (AAT or Nagana) is a vector-borne disease caused by Trypanosomatidae, genus Trypanosoma. The disease is transmitted by the bite of infected hematophagous insects, mainly tsetse flies but also other blood-sucking insects including stomoxes and tabanids. Although many trypanosome species infect animals, the main agents responsible for this disease with a strong socio-economic and veterinary health impact are Trypanosoma congolense (T. congolense or Tc), Trypanosoma vivax (T.vivax), and to a lesser extent, Trypanosoma brucei brucei (T.brucei brucei or Tbb). These parasites mainly infect livestock, including cattle, in sub-Saharan Africa, with major repercussions in terms of animal productivity and poverty for populations which are often already very poor. As there is currently no vaccine, the fight against the disease is primarily based on diagnosis, treatment and vector control. To develop new tools (particularly therapeutic tools) to fight against the disease, we need to know both the biology and the genes involved in the pathogenicity and virulence of the parasites. To date, unlike for Trypanosoma brucei (T.brucei) or Trypanosoma cruzi (T.cruzi), genome editing tools has been relatively little used to study T. congolense. We present an efficient, reproducible and stable CRISPR-Cas9 genome editing system for use in Tc bloodstream forms (Tc-BSF). This plasmid-free system is based on transient expression of Cas9 protein and the use of a ribonucleoprotein formed by the Cas9 and sgRNA complex. This is the first proof of concept of genome editing using CRISPR-Cas9 ribonucleoproteins on Tc-BSF. This adapted protocol enriches the "toolbox" for the functional study of genes of interest in blood forms of the Trypanosoma congolense. This proof of concept is an important step for the scientific community working on the study of trypanosomes and opens up new perspectives for the control of and fight against animal trypanosomosis., Competing Interests: Declaration of competing interest The authors have none to declare., (Copyright © 2023 Elsevier Inc. All rights reserved.)

Drug-resistant trypanosomes are widespread in sub-Saharan Africa and in conjunction with the drug-sensitive phenotypes cause a serious endemic wasting disease in animals. We evaluated the pathogenicity of single and mixed drug-resistant Trypanosoma brucei brucei and T. congolense isolates in 35 female rats, randomly divided into seven groups (1-7) of five rats. Group 1 was the uninfected control. Groups 2 and 3 were infected with drug-sensitive T. brucei brucei and T. congolense, respectively, whereas groups 4 and 5 were infected with multidrug-resistant T. brucei brucei and T. congolense respectively. Group 6 were infected with drug-sensitive T. brucei brucei and T. congolense while group 7 were infected with multidrug-resistant T. brucei brucei and T. congolense. Parasitaemia kinetics, haematological parameters, body weight, clinical signs, survival time, gross and histopathological changes in the spleen were evaluated. Parasitaemia occurred between day 3-9 post-infection in all the infected groups. Rats in groups 4 and 7 had markedly prolonged (p < 0.05) pre-patent period, days to first peak parasitaemia, survival time, and lower (p < 0.05) parasitaemia level than groups 2 and 6 rats while these parameters were comparable for groups 3 and 5 rats. Anaemia was noted in the infected groups but the severity did not vary amongst the infected groups. Severe clinical signs and splenic lesions were noted in rats infected with drug-sensitive trypanosome species compared to the multidrug-resistant species. Therefore, we conclude that the trypanosome isolates were pathogenic. However, the drug-sensitive T. brucei brucei and mixed drug-sensitive trypanosome infections were more pathogenic than their multidrug-resistant counterparts., Competing Interests: Declaration of Competing Interest The authors declare that they have no conflict of interest., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

The involvement of Trypanosoma congolense sialidase alongside phospholipase A 2 has been widely accepted as the major contributing factor to anemia during African animal trypanosomiasis. The enzymes aid the parasite in scavenging sialic acid and fatty acids necessary for survival in the infected host, but there are no specific drug candidates against the two enzymes. This study investigated the inhibitory effects of β-sitosterol on the partially purified T. congolense sialidase and phospholipase A 2 . Purification of the enzymes using DEAE cellulose column led to fractions with highest specific activities of 8016.41 and 39.26 µmol/min/mg for sialidase and phospholipase A 2 , respectively. Inhibition kinetics studies showed that β-sitosterol is non-competitive and an uncompetitive inhibitor of sialidase and phospholipase A 2 with inhibition binding constants of 0.368 and 0.549 µM, respectively. Molecular docking of the compound revealed binding energies of - 8.0 and - 8.6 kcal/mol against the sialidase and phospholipase A 2 , respectively. Furthermore, 100 ns molecular dynamics simulation using GROMACS revealed stable interaction of β-sitosterol with both enzymes. Hydrogen bond interactions between the ligand and Glu284 and Leu102 residues of the sialidase and phospholipase A 2 , respectively, were found to be the major stabilizing forces. In conclusion, β-sitosterol could serve as a dual inhibitor of T. congolense sialidase and phospholipase A 2; hence, the compound could be exploited further in the search for newer trypanocides., (© 2022. The Author(s), under exclusive licence to Springer Nature Switzerland AG.)

Although studies on African Trypanosomiases revealed a variety of trypanosome species in the blood of various animal taxa, animal reservoirs of Trypanosoma brucei gambiense and anatomical niches such as skin have been overlooked in most epidemiological settings. This study aims to update epidemiological data on trypanosome infections in animals from human African trypanosomiasis (HAT) foci of Cameroon. Blood and skin snips were collected from 291 domestic and wild animals. DNA was extracted from blood and skin snips and molecular approaches were used to identify different trypanosomes species. Immunohistochemical analyses were used to confirm trypanosome infections in skin snips. PCR revealed 137 animals (47.1%) with at least one trypanosome species in the blood and/or in the skin. Of these 137 animals, 90 (65.7%) and 32 (23.4%) had trypanosome infections respectively in the blood and skin. Fifteen (10.9%) animals had trypanosome infections in both blood and skin snip. Animals from the Campo HAT focus (55.0%) were significantly (X2 = 17.6; P< 0.0001) more infected than those (29.7%) from Bipindi. Trypanosomes of the subgenus Trypanozoon were present in 27.8% of animals while T. vivax, T. congolense forest type and savannah type were detected in 16.5%, 10.3% and 1.4% of animals respectively. Trypanosoma b. gambiense infections were detected in the blood of 7.6% (22/291) of animals. No T. b. gambiense infection was detected in skin. This study highlights the presence of several trypanosome species in the blood and skin of various wild and domestic animals. Skin appeared as an anatomical reservoir for trypanosomes in animals. Despite methodological limitations, pigs, sheep, goats and wild animals were confirmed as potential reservoirs of T. b. gambiense. These animal reservoirs must be considered for the designing of control strategies that will lead to sustainable elimination of HAT., Competing Interests: The authors have declared that they have no competing interests., (Copyright: © 2023 Magang et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: Tsetse-transmitted African animal trypanosomiasis is recognised as an important disease of ruminant livestock in sub-Saharan Africa, but also affects domestic pigs, with Trypanosoma simiae notable as a virulent suid pathogen that can rapidly cause death. Trypanosoma simiae is widespread in tsetse-infested regions, but its biology has been little studied compared to T. brucei and T. congolense., Methods: Trypanosoma simiae procyclics were cultured in vitro and transfected using protocols developed for T. brucei. Genetically modified lines, as well as wild-type trypanosomes, were transmitted through tsetse flies, Glossina pallidipes, to study T. simiae development in the tsetse midgut, proventriculus and proboscis. The development of proventricular trypanosomes was also studied in vitro. Image and mensural data were collected and analysed., Results: A PFR1::YFP line successfully completed development in tsetse, but a YFP::HOP1 line failed to progress beyond midgut infection. Analysis of image and mensural data confirmed that the vector developmental cycles of T. simiae and T. congolense are closely similar, but we also found putative sexual stages in T. simiae, as judged by morphological similarity to these stages in T. brucei. Putative meiotic dividers were abundant among T. simiae trypanosomes in the proboscis, characterised by a large posterior nucleus and two anterior kinetoplasts. Putative gametes and other meiotic intermediates were also identified by characteristic morphology. In vitro development of proventricular forms of T. simiae followed the pattern previously observed for T. congolense: long proventricular trypanosomes rapidly attached to the substrate and shortened markedly before commencing cell division., Conclusions: To date, T. brucei is the only tsetse-transmitted trypanosome with experimentally proven capability to undergo sexual reproduction, which occurs in the fly salivary glands. By analogy, sexual stages of T. simiae or T. congolense are predicted to occur in the proboscis, where the corresponding portion of the developmental cycle takes place. While no such stages have been observed in T. congolense, for T. simiae putative sexual stages were abundant in the tsetse proboscis. Although our initial attempt to demonstrate expression of a YFP-tagged, meiosis-specific protein was unsuccessful, the future application of transgenic approaches will facilitate the identification of meiotic stages and hybrids in T. simiae., (© 2023. The Author(s).)

Purpose: African animal trypanosomiasis (AAT) is a disease affecting livestock in sub-Saharan Africa. The use of trypanocidal agents is common practice to control AAT. This study aimed to identify drug-resistant Trypanosoma congolense in Lambwe, Kenya, and assess if molecular test backed with mice tests is reliable in detecting drug sensitivity., Methods: Blood samples were collected from cattle, in Lambwe, subjected to buffy coat extraction and Trypanosoma spp. detected under a microscope. Field and archived isolates were subjected to molecular characterization. Species-specific T. congolense and TcoAde2 genes were amplified using PCR to detect polymorphisms. Phylogenetic analysis were performed. Four T. congolense isolates were evaluated individually in 24 test mice per isolate. Test mice were then grouped (n=6) per treatement with diminazene, homidium, isometamidium, and controls. Mice were subsequently assessed for packed cell volume (PCV) and relapses using microscopy., Results: Of 454 samples, microscopy detected 11 T. congolense spp, eight had TcoAde2 gene, six showed polymorphisms in molecular assay. Phylogenetic analysis grouped isolates into five. Two archived isolates were homidium resistant, one was also diminazene resistant in mice. Two additional isolates were sensitive to all the drugs. Interestingly, one sensitive isolate lacked polymorphisms, while the second lacked TcoAde2, indicating the gene is not involved in drug sensitivity. Decline in PCV was pronounced in relapsed isolates., Conclusion: T. congolense associated with homidium and diminazene resistance exist in Lambwe. The impact can be their spread and AAT increase. Polymorphisms are present in Lambwe strains. TcoAde2 is unlikely involved in drug sensitivity. Molecular combined with mice tests is reliable drug sensitivity test and can be applied to other genes. Decline in PCV in infected-treated host could suggest drug resistance., (© 2022. The Author(s) under exclusive licence to Witold Stefański Institute of Parasitology, Polish Academy of Sciences.)

Trypanocidal resistance is a major cause of treatment failure. This study evaluated the sensitivity of Trypanosoma evansi field isolates collected from Marsabit and Isiolo counties, Kenya. A total of 2,750 camels were screened using parasitological tests for trypanosomes. Of the screened camels, 113 tested positive from which 40 T. evansi isolates were tested using the single dose mice sensitivity test. Five treatment groups each comprising of 6 mice were inoculated intraperitoneally with 1x105 trypanosomes of each isolate and treated 24 hours later with isometamidium chloride at 1 mg/kg, homidium chloride at 1mg/kg, diminazene aceturate at 20 mg/kg and quinapyramine sulphate & chloride at 1 mg/kg. The fifth group was left untreated (positive control). The mice were monitored daily for 60 days. A survey on camel owners' practices that influence development of resistance to trypanocidal drugs was then conducted. Results indicated presence of drug resistance in all the 7 study sites that had infected camels. Seven of the isolates tested were resistant to diminazene aceturate whereas, 28, 33 and 34 were resistant to isometamidium chloride, quinapyramine sulphate & chloride and homidium chloride, respectively. Seven (17.5%) isolates of the 40 tested were sensitive to all 4 drugs, whereas, 7.5%, 10%,55% and 10% were resistant to 1,2,3 and 4 drugs, respectively. The prevalence of multiple drug resistance was 75%. Survey data indicated that camel management practices influenced the prevalence and degree of drug resistance. In conclusion, the multiple drug resistance observed in the two counties may not be an indication of total trypanocidal drug failure. Judicious treatment of confirmed trypanosomiasis cases with correct dosage would still be effective in controlling the disease since the observed resistance was at the population and not clonal level. However, integrated control of the disease and the vectors using available alternative methods is recommended to reduce drug use., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2023 Mdachi et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Animal trypanosomosis is an important endemic and wasting disease in sub-Saharan Africa. Its control relies on chemotherapy, and resistance to trypanocides has been widely reported. The pathogenicity of drug-resistant canine trypanosomes is not clear with scanty information available. Thus, this study assessed the comparative pathogenicity of drug-resistant and drug-sensitive Trypanosoma brucei and Trypanosoma congolense infections in dogs. Twenty Nigerian local dogs were used and were randomly assigned into five groups (A-E) of four dogs each. Group A served as the uninfected-control group, while groups B and C were infected with 10 6 drug-sensitive T. congolense and T. brucei. Groups D and E were infected with 10 6 multidrug-resistant T. congolense and T. brucei, respectively. The pre-patent period (PPP), clinical signs, level of parasitaemia (LOP), rectal temperature, body weight, packed cell volume (PCV), red blood cell count (RBC), haemoglobin concentration (HbC), mean corpuscular volume (MCV), mean corpuscular haemoglobin (MCH), mean corpuscular haemoglobin concentration (MCHC), total leucocyte count (TLC) and survivability were assessed. Groups D and E had longer (p < 0.05) mean PPP than groups B and C. Also, group E dogs had lower (p < 0.05) mean LOP, longer (p < 0.05) mean survivability, and higher (p < 0.05) mean body weight, PCV, HbC and RBC than group C dogs. The clinical signs were very severe in group C dogs, compared to group E dogs. However, these parameters did not differ statistically between groups B and D. Thus, multidrug-resistant T. brucei was of lower pathogenicity than drug-sensitive T. brucei, while multidrug-resistant and drug-sensitive T. congolense had comparable pathogenicity following infection in dogs., (© 2022. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

African Trypanosomiasis is a debilitating disease in both humans and animals that occurs in sub-Saharan Africa and has a severe negative impact on the livelihood of people in the affected areas. The disease is caused by protozoan parasites of the genus Trypanosoma, which is often described simply as blood-borne; however, a number of studies have shown the parasite inhabits many different environments within the host. Control of the disease involves measures that include the use of trypanocidal drugs to which there are growing number of reported cases of resistance. Here, the patterns of trypanosome DNA presence during a diminazene aceturate treatment round on a cohort of cattle in Adidome, Ghana were assessed. A group of 24 cows were selected irrespective of age and sex and the infecting trypanosome species followed for 18 days before and after treatment with diminazene aceturate in the blood and skin of the animals using a diagnostic nested PCR that targeted the alpha-beta tubulin gene array. Persistence of trypanosome DNA was observed over the period and parasite DNA was readily detected in both the skin and blood, with parasite DNA disappearing and reappearing in both across the study. Moreover, there was limited correlation between the parasite DNA detected in the skin and blood. Overall, the data show the patterns of a natural trypanosome infection during drug treatment. In addition, the diagnostic potential of sampling the skin for African trypanosomiasis is highlighted., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022. Published by Elsevier B.V.)

Bovine trypanosomiasis caused by Trypanosoma vivax is a relevant disease in domestic ungulates in Latin America, causing different types of livestock losses, particularly in African and South American countries, leading to loss of millions of dollars/year related to dairy and meat production. In addition, T. vivax trypanosomiasis requires intensive veterinary care. While vector control is a feasible measure to manage disease spreading, the search for accurate diagnostic tools still represents a gap in routine veterinary practices and a challenge for the scientific community. The parasite is mechanically transmitted by fomites or by the saliva of haematophagous flies, such as Stomoxys sp. and Tabanus sp., infecting cattle as well as a number of animal hosts. The main symptoms of T. vivax bovine trypanosomiasis are apathy, fever, restricted growth, miscarriage, progressive weakness, neurological signs, pale mucous, loss of appetite, lethargy, and substantial weight loss. In most cases, the presence of animals with subclinical infections, nonspecific symptoms and without apparent parasitaemia presents a challenge when making a diagnosis, which requires accurate methods. Herein, we review state of the art concerning current methods available for the diagnosis of T. vivax bovine trypanosomiasis, focusing on clinical, parasitological, immunological and molecular approaches, highlighting the main features of each method, including "pros and cons". Overall, combining several diagnostic techniques is a better choice since it leads to fewer false negative results and contributes to better disease control., (Copyright© Bentham Science Publishers; For any queries, please email at epub@benthamscience.net.)

Trypanotolerance of the West African dwarf (WAD) breeds may not rule out significant pathophysiological changes that may affect productivity. In this study, the effects of infection of WAD rams with Trypanosoma brucei brucei (Tbb) and Trypanosoma congolense (Tc) on their serum levels of electrolytes [calcium, phosphorus, sodium, potassium]; oxidative stress markers [superoxide dismutase (SOD), malondialdehyde (MDA)]; and sperm parameters [sperm count, motility, vitality, and morphology] were investigated. Fifteen WAD rams, assigned to 3 groups (A, B & C) of 5 rams each, were used for the study. Group A rams were infected with Tbb, while Group B rams were infected with Tc, both intraperitoneally, at the dose of 10 6 trypanosomes/animal. Group C rams served as the uninfected control. The infections were monitored for 70 days. Serum calcium levels were significantly (p < 0.05) lower in Tbb and Tc infected rams compared to the control throughout the study. Serum sodium was significantly (p < 0.05) higher in the Tb infected rams compared to the Tc infected and control rams on days 14 and 28 PI. Serum SOD activity decreased while MDA levels increased in both infected groups of rams. Tbb infected rams were azoospermic, while Tc infected rams had lower sperm motility, vitality and concentration, and higher number of abnormal sperm cells compared to the control. Necrotic and inflammatory lesions occurred in the testis and epididymis of both infected rams. These results suggest that despite trypanotolerance, trypanosome infections in the WAD rams significantly impact on health and reproduction., (© 2022. The Author(s), under exclusive licence to Springer Nature B.V.)

African trypanosomoses, whose pathogens are transmitted by tsetse flies, are a threat to animal and human health. Tsetse flies observed at the military base of the French Forces in Côte d'Ivoire (FFCI base) were probably involved in the infection and death of military working dogs. Entomological and parasitological surveys were carried out during the rainy and dry seasons using "Vavoua" traps to identify tsetse fly species, their distribution, favorable biotopes and food sources, as well as the trypanosomes they harbor. A total of 1185 Glossina palpalis palpalis tsetse flies were caught, corresponding to a high average apparent density of 2.26 tsetse/trap/day. The results showed a heterogeneous distribution of tsetse at the FFCI base, linked to more or less favorable biotopes. No significant variation in tsetse densities was observed according to the season. The overall trypanosomes infection rate according to microscopic observation was 13.5%. Polymerase chain reaction (PCR) analyses confirmed the presence of Trypanosoma vivax and T. congolense forest type, responsible for African animal trypanosomosis. Our findings suggest that there is a risk of introduction and transmission of T. brucei gambiense, responsible for human African trypanosomiasis, on the study site. This risk of transmission of African trypanosomes concerns not only the FFCI base, but also inhabited peripheral areas. Our study confirmed the need for vector control adapted to the eco-epidemiological context of the FFCI base., (© Y.J.R. Konan et al., published by EDP Sciences, 2023.)

Although a diversity of trypanosome species have been detected in various animal taxa from human African trypanosomosis (HAT) foci, cattle trypanosomosis has not been addressed in HAT foci of west and central African countries including Chad. This study aimed to determine the prevalence of pathogenic trypanosome species in cattle from three HAT foci of the south of Chad. Blood samples were collected from 1466 randomly selected cattle from HAT foci of Mandoul, Maro, and Moïssala in the south of Chad. For each animal, the sex, age and body condition were recorded. Rapid diagnostic test (RDT) was used to search Trypanosoma brucei gambiense antibodies while the capillary tube centrifugation (CTC) test and PCR-based methods enabled to detect and identify trypanosome species. From the 1466 cattle, 45 (3.1%) were positive to RDT. The prevalence of trypanosome infections revealed by CTC and PCR-based method were respectively 2.7% and 11.1%. Trypanosomes of the subgenus Trypanozoon were dominant (6.5%) followed by T. congolense savannah (2.9%), T. congolense forest (2.5%) and T. vivax (0.8%). No animal was found with DNA of human infective trypanosome (T. b. gambiense). The overall prevalence of trypanosome infections was significantly higher in animal from the Maro HAT focus (13.8%) than those from Mandoul (11.1%) and Moïssala HAT foci (8.0%). This prevalence was also significantly higher in animal having poor body condition (77.5%) than those with medium (11.2%) and good (0.5%) body condition. The overall prevalence of single and mixed infections were respectively 9.4% and 1.6%. This study revealed natural infections of several pathogenic trypanosome species in cattle from different HAT foci of Chad. It showed similar transmission patterns of these trypanosome species and highlighted the need of developing control strategies for animal African trypanosomosis (AAT) with the overarching goal of improving animal health and the economy of smallholder farmers., Competing Interests: The authors have declared that no competing interests exist., (Copyright: © 2022 Vourchakbé et al. This is an open access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.)

Background: With the largest cattle population in Africa and vast swathes of fertile lands infested by tsetse flies, trypanosomosis is a major challenge for Ethiopian farmers. Managing the problem strategically and rationally requires comprehensive and detailed information on disease and vector distribution at the national level. To this end, the National Institute for Control and Eradication of Tsetse and Trypanosomosis (NICETT) developed a national atlas of tsetse and African animal trypanosomosis (AAT) for Ethiopia., Methods: This first edition of the atlas focused on the tsetse-infested areas in western Ethiopia. Data were collected between 2010 and 2019 in the framework of national surveillance and control activities. Over 88,000 animals, mostly cattle, were tested with the buffy-coat technique (BCT). Odour-enhanced traps were deployed in approximately 14,500 locations for the entomological surveys. Animal- and trap-level data were geo-referenced, harmonized and centralized in a single database., Results: AAT occurrence was confirmed in 86% of the districts surveyed (107/124). An overall prevalence of 4.8% was detected by BCT in cattle. The mean packed cell volume (PCV) of positive animals was 22.4, compared to 26.1 of the negative. Trypanosoma congolense was responsible for 61.9% of infections, T. vivax for 35.9% and T. brucei for 1.7%. Four tsetse species were found to have a wide geographic distribution. The highest apparent density (AD) was reported for Glossina pallidipes in the Southern Nations, Nationalities and People's Region (SNNPR) (3.57 flies/trap/day). Glossina tachinoides was the most abundant in Amhara (AD 2.39), Benishangul-Gumuz (2.38), Gambela (1.16) and Oromia (0.94) regions. Glossina fuscipes fuscipes and G. morsitans submorsitans were detected at lower densities (0.19 and 0.42 respectively). Only one specimen of G. longipennis was captured., Conclusions: The atlas establishes a reference for the distribution of tsetse and AAT in Ethiopia. It also provides crucial evidence to plan surveillance and monitor control activities at the national level. Future work on the atlas will focus on the inclusion of data collected by other stakeholders, the broadening of the coverage to tsetse-free areas and continuous updates. The extension of the atlas to data on control activities is also envisaged., (© 2022. The Author(s).)

In tsetse-infested areas of Ethiopia, African Animal Trypanosomiasis is the most serious threat to livestock productivity. A cross-sectional study was conducted from May 2021 to September 2021 in the Zaba Gazo district to assess the prevalence and associated risk factors of bovine trypanosomiasis through parasitological and hematological techniques. In the current study, the overall prevalence of trypanosomiasis was found to be 21%. Among anticipated risk factors, the origin of animals has shown a statistically significant association (p < 0.05) with the occurrence of bovine trypanosomiasis. Other potential risk factors, such as sex, age, BCS, coat color, and agroecology, were not shown to have a statistically significant relationship (p > 0.05) with trypanosomiasis. The overall mean PCV values for parasitaemic and aparasitaemic cattle were 23.24 ± 3.04SD and 27.37 ± 4.18SD, respectively, thus it was lower in parasitaemic animals than the aparasitaemic animals. A high prevalence of bovine trypanosomiasis in the study area necessitates an integrated parasite and vector control approach to curve the prevalence and effect of the disease., Competing Interests: Declaration of Competing Interest All authors declared no competing conflict of interest., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

The main effects of trypanosomosis in Brazil are related to reproductive alterations. In this context, the present study aimed to report the occurrence of abortions in goats and sheeps in the semiarid region of Northeastern Brazil, associated with Trypanosoma vivax. Trypomastigotes forms visualized by Buffy coat technique (BCT) method in 68.7% of the goats and 50.0% of the ewes that aborted. PCR identified that 100% of the goats and ewes that aborted were infected with T. vivax. The goats and ewes that aborted showed high parasitemia and developed clinical signs of trypanosomosis. The presence of T. vivax DNA was identified in the blood of fetuses by the PCR technique, proving infection by T. vivax in aborted fetuses, as well as confirming the congenital transmission of the parasite., (Copyright © 2022 Elsevier Ltd. All rights reserved.)

Control programmes for African animal trypanosomiasis (AAT) in livestock have been mainly focused on cattle with very little focus on goats, an important reservoir for the disease. Using the polymerase chain reaction (PCR), this study investigated trypanosome infection in village goats in Mambwe, a rural District in Eastern Zambia. Filter paper blood spots were collected from 326 goats and tested for infection with Trypanosoma congolense, Trypanosoma vivax and Trypanosoma brucei s.l. using ribosomal RNA internal transcribed spacers (ITS)-PCR. The frequency of trypanosomes from the sampled goats was 4.6% (95% CI = 2.3-6.8). Results indicated significantly high infections with Trypanosoma vivax (4.0%; 95% CI = 1.9-6.1) than T. congolense (0.6%; 95% CI =  - 0.2 to 1.5), and T. brucei (0.0%), P = 0.04. Findings show the circulation of trypanosomes that causes AAT in goats and that they may pose serious threats to not only goats but also to other livestock reared alongside goats., (© 2022. The Author(s).)

Animal African Trypanosomiasis (AAT) remains an animal health problem in sub-Saharan Africa and in Cameroon in particular. Despite more than 40 years of fighting against AAT in some tsetse infested areas, the disease prevalence is still a concern. Improving the control strategies in different settings requires to understand the current epidemiological situation of AAT. The aim of the present study was to update our knowledge on the diversity of tsetse fauna and trypanosome species in the tsetse infested area of Faro and Deo division, Adamawa region, Cameroon. Tsetse flies were caught using Vavoua trap in two villages and the apparent density per trap (ADP) were estimated. After morphological identification of tsetse fly species, flies were dissected and their midguts recovered. The presence of blood meal residues was recorded. Trypanosomes species were checked in the flies' midguts by microscopy followed by PCR method. The vertebrate taxa on which tsetse flies have taken blood meal were determined using the heteroduplex-PCR method. A total of 338 tsetse flies including 11 teneral flies (10 Glossina palpalis palpalis and 01 G. morsitans submorsitans) and 327 non-teneral were trapped in Mayo Lainde and Tchabal Mbabo. Amongst the caught tsetse flies, of the 327 non-teneral flies, 315 (96.3%) were G. p. palpalis, 8 (2.4%) were G. morsitans submorsitans and 4 (1.2%) G. fuscipes fuscipes. Trypanosome infections including Trypanosoma congolense forest (19.88%) and savanah (2.53%) "types", T. brucei s.l. (7.30%) and T. vivax (2.85%) were identified in 45.08% of non-teneral flies (32.38% for single infection and 12.70% for mixed infection). Amongst the 54 blood meals identified in tsetse midguts, 41% were from humans, 33% from cattle and 26% from other vertebrate hosts. About 51.9% of blood meals were found with various trypanosome species including 42.6% with T. congolense and 24% with T. brucei s.l. This study revealed the presence of three tsetse taxa and the circulation of four trypanosome taxa in villages of the Faro and Deo division. About 45% of captured tsetse fly are infected with trypanosome species causing AAT. Tsetse flies feed on humans, cattle and many other vertebrates. Strategies to eliminate the vectors must be improved to reduce the pathological impacts of trypanosome infections in this area., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Trypanosomosis of the West African Dwarf (WAD) sheep is often neglected due to emphasis on trypanotolerance. Nevertheless, significant pathological changes may occur in tissues of infected WAD sheep. The purpose of this study was to evaluate the brain, pituitary, and adrenal lesions of Trypanosoma brucei brucei (Tbb) and Trypanosoma congolense (Tc) infections in WAD rams. Fifteen WAD rams were infected intraperitoneally with Tbb or Tc (10 6 trypanosomes/animal) or were uninfected controls (5 rams per group). Adrenocorticotrophic hormone (ACTH) and cortisol were assayed in serum by enzyme immunoassay technique. The brain, pituitary, and adrenal glands were processed for histopathology. Serum ACTH levels of infected rams were significantly ( P < .05) higher than that of controls on days 14 and 70 post infection (PI). Serum cortisol levels of infected rams were significantly ( P < .05) higher than that of controls only on day 14 PI. Mortality was 60% in Tbb- and 40% in Tc-infected rams. The brain of the infected groups showed chromatolysis of cortical neurons and Purkinje cells with severe encephalitis. Degenerative, necrotic, and inflammatory changes were seen in the pituitary and adrenal glands of the infected rams. Adrenal corticomedullary ratio was significantly ( P < .05) higher in Tc-infected rams than controls. Based on the high mortality levels, likely due to severe encephalitis, the WAD sheep may not be regarded as trypanotolerant.

After intensive control efforts, human African trypanosomiasis (HAT) was declared eliminated in Côte d'Ivoire as a public health problem in December 2020 and the current objective is to achieve the interruption of the transmission (zero cases). Reaching this objective could be hindered by the existence of an animal reservoir of Trypanosoma (T.) brucei (b.) gambiense. In the framework of a study led in 2013 to assess the role of domestic animals in the epidemiology of HAT in the two last active foci from Côte d'Ivoire (Bonon and Sinfra), plasmas were sampled from four species of domestic animals for parasitological (microscopic examination by the buffy coat technique (BCT)), serological (immune trypanolysis (TL)) and molecular (specific PCR: TBR for T. brucei s.l., TCF for T. congolense forest type, TVW for T. vivax and PCR for T. b. gambiense) testing. In order to improve the understanding of the involvement/role of these animals in the transmission of T. b. gambiense, we have quantified in this study the IgG response to whole saliva extracts of Glossina palpalis gambiensis in order to perform an association analysis between anti-saliva responses and the positivity of diagnostic tests. Cattle and pigs had significantly higher rates of anti-tsetse saliva responses compared to goats and sheep (p < 0.01). In addition, the anti-tsetse saliva responses were strongly associated with the parasitology (BCT+), serology (TL+) and PCR (TBR+ and TCF+) results (p < 0.001). These associations indicate a high level of contacts between the positive/infected animals and tsetse flies. Our findings suggest that protecting cattle and pigs against tsetse bites could have a significant impact in reducing transmission of both animal and human trypanosome species, and advocates for a "One health" approach to better control African trypanosomosis in Côte d'Ivoire., (Copyright © 2022 Elsevier B.V. All rights reserved.)

The present work investigated the presence of Trypanosoma vivax in semen and reproductive tissues of experimentally infected cattle and evaluated changes in seminal parameters. Two groups of cattle were established: T01 - experimentally infected with T. vivax (n = 8) and T02 - not experimentally infected with T. vivax (n = 8). After infection, blood (every seven days until 182 days post-infection - DPI), semen (7, 14, 35, 56, 70, 120 and 182 DPI) and reproductive tissue (after euthanasia, 182 DPI) were collected to search for T. vivax using different techniques, including PCR, Woo and Brener. Seminal parameters, including turbulence, motility, concentration, and vigor, were also analyzed. Packed cell volume (PCV) of the animals was determined weekly and weight gain was calculated. The PCR revealed T. vivax DNA in 7/56 semen samples of post-infection T01 cattle. Trypanosoma vivax DNA was detected in the semen of 5/8 animals at 7, 14, 56, 70 and 120 DPI, in the testis of four, and in the epididymis and fat located around the testis of two others. Trypomastigote forms of T. vivax were not found in any semen sample. Sperm of T01 cattle had lower turbulence (p ≤ 0.05) at 7, 14, 35, 56, 120 and 182 DPI, lower vigor (p ≤ 0.05) at 120 DPI and more sperm abnormalities (p ≤ 0.05) than T02. Digital dermatitis was observed among T01 cattle. Animals of T01 had lower PCV values than did those of T02 for most of the evaluations performed and T02 animals gained more weight during the experiment. The results highlight the presence of T. vivax DNA in semen of infected cattle and the importance of this disease for male breeding cattle. Further research is needed to determine whether T. vivax can be sexually transmitted in cattle., (Copyright © 2022 Elsevier B.V. All rights reserved.)

Domestic and wild animals are important reservoirs of the rhodesiense form of human African trypanosomiasis (rHAT), however quantification of this effect offers utility for deploying non-medical control activities, and anticipating their success when wildlife are excluded. Further, the uncertain role of animal reservoirs-particularly pigs-threatens elimination of transmission (EOT) targets set for the gambiense form (gHAT). Using a new time series of high-resolution cattle and pig density maps, HAT surveillance data collated by the WHO Atlas of HAT, and methods drawn from causal inference and spatial epidemiology, we conducted a retrospective ecological cohort study in Uganda, Malawi, Democratic Republic of the Congo (DRC) and South Sudan to estimate the effect of cattle and pig density on HAT risk. For rHAT, we found a positive effect for cattle (RR 1.61, 95% CI 0.90, 2.99) and pigs (RR 2.07, 95% CI 1.15, 2.75) in Uganda, and a negative effect for cattle (RR 0.88, 95% CI 0.71, 1.10) and pigs (RR 0.42, 95% CI 0.23, 0.67) in Malawi. For gHAT we found a negative effect for cattle in Uganda (RR 0.88, 95% CI 0.50, 1.77) and South Sudan (RR 0.63, 95% CI 0.54, 0.77) but a positive effect in DRC (1.17, 95% CI 1.04, 1.32). For pigs, we found a positive gHAT effect in both Uganda (RR 2.02, 95% CI 0.87, 3.94) and DRC (RR 1.23, 95% CI 1.10, 1.37), and a negative association in South Sudan (RR 0.66, 95% CI 0.50, 0.98). These effects did not reach significance for the cattle-rHAT effect in Uganda or Malawi, or the cattle-gHAT and pig-gHAT effects in Uganda. While ecological bias may drive the findings in South Sudan, estimated E-values and simulation studies suggest unmeasured confounding and underreporting are unlikely to explain our findings in Malawi, Uganda, and DRC. Our results suggest cattle and pigs may be important reservoirs of rHAT in Uganda but not Malawi, and that pigs-and possibly cattle-may be gHAT reservoirs., Competing Interests: The authors have declared that no competing interests exist.

Background: Animal African Trypanosomosis (AAT) is a parasitic disease of livestock that has a major socio-economic impact in the affected areas. It is caused by several species of uniflagellate extracellular protists of the genus Trypanosoma mainly transmitted by tsetse flies: T. congolense, T. vivax and T. brucei brucei. In Burkina Faso, AAT hampers the proper economic development of the southwestern part of the country, which is yet the best watered area particularly conducive to agriculture and animal production. It was therefore important to investigate the extent of the infection in order to better control the disease. The objective of the present study was to assess the prevalence of trypanosome infections and collect data on the presence of tsetse flies., Methods: Buffy coat, Trypanosoma species-specific PCR, Indirect ELISA Trypanosoma sp and trypanolysis techniques were used on 1898 samples collected. An entomological survey was also carried out., Results: The parasitological prevalence of AAT was 1.1%, and all observed parasites were T. vivax. In contrast, the molecular prevalence was 23%, of which T. vivax was predominant (89%) followed by T. congolense (12.3%) and T. brucei s.l. (7.3%) with a sizable proportion as mixed infections (9.1%). T. brucei gambiense, responsible of sleeping sickness in humans, was not detected. The serological prevalence reached 49.7%. Once again T. vivax predominated (77.2%), but followed by T. brucei (14.7%) and T. congolense (8.1%). Seven samples, from six cattle and one pig, were found positive by trypanolysis. The density per trap of Glossina tachinoides and G. palpalis gambiensis was 1.2 flies., Conclusions/significance: Overall, our study showed a high prevalence of trypanosome infection in the area, pointing out an ongoing inadequacy of control measures., Competing Interests: The authors have declared that no competing interests exist.

African animal trypanosomiasis (AAT) a parasitic disease of livestock in sub-Saharan Africa causing tremendous loses. Sub-Saharan continental estimation of mean prevalence in both large and small domestic animals, risk factors, tsetse and non-tsetse prevalence and drug resistance is lacking. A review and meta-analysis was done to better comprehend changes in AAT prevalence and drug resistance. Publish/Perish software was used to search and extract peer-reviewed articles in Google scholar, PubMed and CrossRef. In addition, ResearchGate and African Journals Online (AJOL) were used. Screening and selection of articles from 2000-2021 was performed according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA). Articles 304 were retrieved; on domestic animals 192, tsetse and non-tsetse vectors 44, risk factors 49 and trypanocidal drug resistance 30. Prevalence varied by, host animals in different countries, diagnostic methods and species of Trypanosoma. Cattle had the highest prevalence with Ethiopia and Nigeria leading, T. congolense (11.80-13.40%) and T. vivax (10.50-18.80%) being detected most. This was followed by camels and pigs. Common diagnostic method used was buffy coat microscopy. However; polymerase chain reaction (PCR), CATT and ELISA had higher detection rates. G. pallidipes caused most infections in Eastern regions while G. palpalis followed by G. mortisans in Western Africa. Eastern Africa reported more non-tsetse biting flies with Stomoxys leading. Common risk factors were, body conditions, breed type, age, sex and seasons. Ethiopia and Nigeria had the highest trypanocidal resistance 30.00-35.00% and highest AAT prevalence. Isometamidium and diminazene showed more resistance with T. congolense being most resistant species 11.00-83.00%., (© The Author(s) 2022. Published by Oxford University Press on behalf of Entomological Society of America. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.)

The role of Sialyltransferases (STs) specifically subfamilies ST3Gal1 and ST6Gal1 tissue expression was investigated in the liver and kidney of Trypanosoma brucei brucei-infected and uninfected control pigs. The study was aimed to provide emerging target for treatment. Pigs were experimentally infected with 2 × 10 6  T. b. brucei (Federe strain); parasitemia was monitored by microscopy and tissue expression levels of ST3Gall and ST6Gall in the liver and kidney were assessed using quantitative real-time polymerase chain reaction (qRT-PCR). Parasitemia were undulating and anemia occurred significantly (P < 0.01) on day 13 in the infected pigs with an attempt to recover toward the termination of the study on day 21. The gene expressions for hepatic and renal ST3Gal1 and ST6Gal1 were significantly (P < 0.0001) upregulated 5-42 folds in the infected pig compared to the non-infected control group. It was concluded from the findings in this study that increased tissue expression of ST3Gal1 and ST6Gal1 in T b. brucei-infected pigs may play a pivotal role in the resialylation of desialylated red blood cells, thereby promoting recovery of the red blood cells and stabilization of erythrocyte mass in trypanosome-infected pigs. It is recommended that the expression of serum ST3Gal1 and ST6Gal1 be investigated further, in trypano-susceptible against trypano-tolerant breeds of animals to determine the role of these genes in trypano-tolerance., (Copyright © 2022. Published by Elsevier Ltd.)

Objectives: This study demonstrated the enhancing actions of probiotic on the antitrypanosomal effects of diminazene aceturate in dogs experimentally infected with Trypanosoma brucei brucei ., Methods: Twenty (20) apparently healthy adult local dogs of both sexes were randomly divided into five groups each containing four dogs. Group I were uninfected and untreated while groups III, IV and V were infected. Groups II, III, IV and V were administered multispecies probiotic (MSP) and/or diminazene aceturate (DA). Parasitaemia was determined, clinical signs recorded and blood collected for haematology., Results: Results revealed T. b. brucei prepatent periods of 4.75 ± 0.25, (4-5) days and significant decrease of parasitaemia, clinical signs and mortality in groups IV and V compared to group III. Mortalities of 100% (group III), 25% (group IV) and 0% (group V) were recorded. Mean packed cells volume, haemoglobin concentration and red blood cells count showed no significant difference in groups I, II, and V, but were significantly decreased in groups III and IV post-treatment., Conclusions: The administration of MSP to infected dogs enhanced the antitrypanosomal effects of diminazene aceturate., (© 2022 Walter de Gruyter GmbH, Berlin/Boston.)