Trypanosome Infection Research Articles

Spiroplasma endosymbiont reduction of host lipid synthesis and Stomoxyn-like peptide contribute to trypanosome resistance in the tsetse fly Glossina fuscipes.

The tsetse fly, Glossina fuscipes fuscipes ( Gff ) is of high public health relevance. Gff exhibits strong innate resistance to trypanosomes, especially when infected with the endosymbiotic bacterium Spiroplasma . This study investigated how the bacterium Spiroplasma inside Gff enables them to be resistant to trypanosome infection. Our results indicate alterations in host lipid metabolism with reduction in levels of triglycerides, suggesting a potential metabolic barrier that limits the viability to parasite. In addition, we discovered a small peptide, stomoxyn, exclusively in Gff and related Palpalis tsetse species. We have shown that Gff synthetic Stomoxyn has antibacterial and antitrypanosomal properties and lowering Stomoxyn levels in Gff correlates with increased parasite prevalence. We suggest that strategies to increase Spiroplasma prevalence or enhance stomoxyn expression through paratransgenic approaches could be promising avenues for reducing trypanosomiasis transmission.

Diversity of trypanosomes in tsetse fly caught in two “silent” sleeping sickness foci of Bafia and the Manoka Island in Cameroon

BackgroundSurveillance of “silent” human African Trypanosomiasis (HAT) foci is important for the achievement of the World Health Organization (WHO) goal of interrupting the transmission of this disease by 2030. It is in this context that this study was carried out to determine the trypanosome species circulating in the “silent” HAT foci of Bafia and the Manoka island in Cameroon. MethodsIn the Bafia and Manoka HAT foci, georeferenced pyramidal traps were used to trap tsetse flies. After DNA extraction from each whole fly, molecular tools were used to detect different trypanosome species as well as the origin of tsetse fly blood meals. Geographical information system was used to map the trypanosome infections and entomological data and to localize areas at high risk for trypanosome transmission. ResultsFor this study, 1683 tsetse flies were caught and the relative apparent densities was 2.96: 0.03 in the Bafia HAT focus and 5.23 in the Manoka island. For the molecular identification of trypanosomes, 708 non-teneral tsetse flies (8 from Bafia and 700 from Manoka) were randomly selected. The overall trypanosome infection rate was 7.34 % with no infection in the Bafia HAT focus. Among the analysed flies, 4.57 % had trypanosomes of the subgenus Trypanozoon while 4.1 % and 1.13 % had respectively T. congolense and T. vivax. The most common mixed infections were the combination of trypanosomes of the subgenus Trypanozoon and T. congolense. Of the 708 tsetse flies analysed, 134 (18.93 %) tsetse flies were found with residual blood meals, 94 % and 6 % were respectively from humans and dogs. The trapping sites of Plateau, Sandje and Hospital appeared as the areas where contact with tsetse flies is most common. ConclusionThis study revealed a discrepancy in the abundance tsetse flies as well as the trypanosome infection rates in tsetse of the two “silent” HAT foci of Cameroon. The detection of different trypanosome species in tsetse from the Manoka Island highlights their transmission. The high percentage of human blood meals in tsetse flies indicates an important contact between tsetse flies and human; emphasizing the risk of trypanosome transmission to human in this island.

Agonistic song rate positively correlates with male breeding success and avian malaria infection in Acrocephalus paludicola (Aquatic Warbler), a promiscuous songbird with female-only parental care

Abstract The link between male song and reproductive success has been explored at length in socially monogamous birds, but results were inconsistent and under-represented socially non-monogamous species with uniparental care. Here, we evaluated whether metrics of male song in Acrocephalus paludicola (Aquatic Warbler), a promiscuous songbird with female-only care and large repertoires, are associated with fitness- and quality-related traits. We showed that the number of 9-day-old nestlings fathered and probability of avian malaria infection increased with the rate of agonistic song, produced in male–male interactions, and that male-scaled mass index (proxy for energy reserves) positively correlated with the repertoire size. The male breeding success was not explained by repertoire size and song duty cycle. None of the song variables clearly explained the male return rate or change in the tarsus length (proxy for structural body size) and scaled mass index of the fathered chicks between days 2 and 9 post-hatch. No other relationships between the song characteristics and the inbreeding coefficient, scaled mass index, wing-length and Trypanosoma infection status of the males were supported, and Plasmodium infection was unrelated to the song duty cycle and repertoire size. We conclude that in male A. paludicola the repertoire size could be a signal of early developmental stress or current body condition, and the agonistic song rate could be shaped by sexual selection and signal to females a genetic makeup that enhances survival upon infection by Plasmodium.

Tsetse fly density and trypanosoma infection rate in Bedele and Dabo Hana districts of Buno Bedele Zone, Southwest Ethiopia

BackgroundTrypanosomiasis is an infectious disease caused by parasitic protozoa of the genus Trypanosome and primarily transmitted by tsetse flies. This study aimed to determine the density of tsetse flies and the rate of trypanosome infection in the Bedele and Dabo Hana districts of the Buno Bedele Zone in Ethiopia.ResultsA cross-sectional study was conducted from January to February 2023 to catch tsetse flies, determine tsetse density, and estimate the trypanosome infection rate. We used 100 traps (40 NGU, 30 pyramidal, and 30 biconical) to catch the flies. The following standard procedures were followed to identify the specific trypanosome species in the collected tsetse flies: The flies were dissected, and the salivary glands were removed. We placed the salivary glands in a drop of saline solution on a microscope slide. A coverslip was placed over the salivary glands, the slide was examined under a microscope, and the trypanosomes were identified based on their morphology. A total of 3,740 tsetse flies were captured from 100 traps, resulting in an overall apparent density of 18.7 flies per trap per day. Within the study area, only one species of tsetse fly, Glossina tachinoides, was identified. Of the 1,320 dissected Glossina tachinoides, 1.82% were found to be infected with trypanosome parasites. Among these infections, 58.33% were attributed to Trypanosoma congolense, while the remaining 41.67% were caused by Trypanosoma brucei. The infection rate of trypanosomes was significantly higher in female tsetse flies (87.5%) as compared to male flies (12.5%). Furthermore, a significantly higher infection rate was observed in flies older than 20 days (83.33%) and in hunger stage 1 flies (58.33%) compared to hunger stages 2, 3, and 4.ConclusionsThis study highlights the necessity of implementing control and suppression measures targeting the vector (tsetse flies) and the parasite (trypanosomes) to effectively manage and prevent pathogenic animal trypanosomiasis.

Trypanosoma Infection in Freshwater Fish and Its Corellation with Water Quality

Trypanosoma Infection in Freshwater Fish and Its Corellation with Water Quality

Symbiotic bacteria Sodalis glossinidius, Spiroplasma sp and Wolbachia do not favour Trypanosoma grayi coexistence in wild population of tsetse flies collected in Bobo-Dioulasso, Burkina Faso.

Tsetse flies, the biological vectors of African trypanosomes, have established symbiotic associations with different bacteria. Their vector competence is suggested to be affected by bacterial endosymbionts. The current study provided the prevalence of three tsetse symbiotic bacteria and trypanosomes in Glossina species from Burkina Faso. A total of 430 tsetse flies were captured using biconical traps in four different collection sites around Bobo-Dioulasso (Bama, Bana, Nasso, and Peni), and their guts were removed. Two hundred tsetse were randomly selected and their guts were screened byPCR for the presence of Sodalis glossinidius, Spiroplasmasp., Wolbachia and trypanosomes. Of the 200 tsetse, 196 (98.0%) were Glossina palpalis gambienseand 4 (2.0%) Glossina tachinoides. The overall symbiont prevalence was 49.0%, 96.5%, and 45.0%, respectively for S. glossinidius, Spiroplasma and Wolbachia. Prevalence varied between sampling locations: S. glossinidius(54.7%, 38.5%, 31.6%, 70.8%); Spiroplasma (100%, 100%, 87.7%, 100%); and Wolbachia(43.4%, 38.5%, 38.6%, 70.8%),respectively in Bama, Bana, Nasso and Peni. Noteworthy, no G. tachhnoideswas infected by S. glossinidius and Wolbachia, but they were all infected by Spiroplasma sp. A total of 196 (98.0 %) harbored at least one endosymbionts. Fifty-five (27.5%) carried single endosymbiont. Trypanosomes were found only in G.p. gambiense, but not G. tachinoides. Trypanosomes were present in flies from all study locations with an overall prevalence of 29.5%. In Bama, Bana, Nasso, and Peni, the trypanosome infection rate was respectively 39.6%, 23.1%, 8.8%, and 37.5%. Remarkably, only Trypanosoma grayi was present. Of all trypanosome-infected flies, 55.9%, 98.3%, and 33.9% hosted S. glossinidius, Spiroplasma sp and Wolbachia, respectively. There was no association between Sodalis, Spiroplasma and trypanosome presence, but there was a negative association with Wolbachia presence. We reported1.9 times likelihood of trypanosome absence when Wolbachia was present. This is the first survey reporting the presence of Trypanosoma grayi in tsetse from Burkina Faso. Tsetse from these localities were highly positive for symbiotic bacteria, more predominantly with Spiroplasma sp. Modifications of symbiotic interactions may pave way for disease control.

Trypanosoma infection and bloodmeal analysis in post-feeding sand flies across Thailand

Phlebotomine sand flies are recognized as a primary vector of Leishmania and are also suspected vectors of Trypanosoma. The transmission cycle of these parasites relies on the distribution of sand fly vectors, parasites, and reservoir animals. This study aimed to detect Leishmania and Trypanosoma DNA and identify the sources of bloodmeals in post-feeding sand flies captured across Thailand. A total of 42,911 field female sand flies were collected from 11 provinces across Thailand using CDC light traps. Among these, 253 post-feeding sand flies were selected for analysis. The predominant species in this study was Sergentomyia khawi (33.60 %). The DNA was extracted from individual female sand flies. Polymerase chain reaction (PCR), specific to the internal transcribed spacer 1 (ITS1) and the small subunit ribosomal RNA (SSU rRNA) gene regions were used to detect the presence of Leishmania and Trypanosoma DNA, respectively. Additionally, cytochrome c oxidase subunit I (COI) gene region was utilized to identify the sources of host bloodmeals. Leishmania DNA was not detected in any specimens. The analysis of SSU rRNA sequences revealed the presence of Trypanosoma DNA (11.46 %, 29/253) in sand fly samples. Among these samples, T. noyesi (1.58 %, 4/253) was identified in Idiophlebotomus longiforceps and Phlebotomus asperulus, Trypanosoma Anura01+02/Frog2 (1.18 %, 3/253) in Se. khawi, and Trypanosoma Anura04/Frog1 (8.70 %, 22/253) in Se. khawi, Se. hivernus and Grossomyia indica. Bloodmeal analysis utilizing the COI gene revealed a diverse range of vertebrate hosts’ blood, including bird, bat, frog and sun skink. Our findings confirm the presence of Trypanosoma DNA and identify the sources of bloodmeals from vertebrate hosts in various sand fly species, suggesting their potential as possible vectors for Trypanosoma in Thailand. Furthermore, our study is the first to provide molecular evidence using the COI gene to identify frogs as a host blood source for sand flies in Thailand. Further studies focusing on the isolation of live parasites in sand flies to confirm vector potential and examining the role of animal reservoirs will enhance our understanding of the host-parasite relationship and enable more efficient control for disease transmission.

Bovine trypanosomosis, vector distribution and infection rate in three districts of Gamo Zone, southwestern Ethiopia

African animal trypanosomosis is one of the main obstacles to the development of livestock and agricultural output in Ethiopia. It usually results in a severe, frequently fatal sickness, and the infected animals were more weakened as the disease progress and become unfit for work. A cross sectional study design was conducted from December 2021 to April 2022 with the aim of estimating the prevalence of trypanosome infection both in Glossina spp. and cattle, and to assess apparent density of Glossina spp. A total of 298 cattle were selected and examined for trypanosome by using buffy coat technique. The overall prevalence of bovine trypanosomosis was 19.1%; and two species of trypanosomes, T. congolense and T. vivax, were identified in the study area. The prevalence of T. congolense and T. vivax were 15.8% and 2.3%, respectively. The prevalence of trypanosomosis was significantly higher in adult animals (OR = 2.7; p < 0.05) than in younger cattle and poor body condition (OR = 3.18; p < 0.05) than medium body condition animals. The mean PCV value of infected animals was 14.3% (13.3–15.4) significantly lower than the non-infected animals 18.5% (17.8–19.2). Glossina pallidipes is the only tsetse species encountered in all the study areas. In total, 2992 flies were caught of which 90.8% belong to G. pallidipes and 9.2% were other biting flies. The overall apparent density of G. pallidipes was 20.1 F/T/D and other biting flies were 2.0 F/T/D. A total of 307 live Glossina pallidipes were dissected. The overall prevalence of Glossina pallidipes infection rate was 9.1% (95% CI = 5.9–12.4). The prevalence of G. pallidipes infection was significantly higher in Kucha district (OR = 3.2, χ2 = 2.6, p < 0.05) than the other two districts, Daramalo and Arba Minch Zuria. Also it was significantly higher in flies trapped from riverine forest areas (OR = 5.5, χ2 = 2.86, p < 0.05). Therefore, to reduce the impact of trypanosomosis and Glossina, vector control and treating infected cattle with prophylactic or chemotherapeutic drugs and active community participation can play a key role.

Iatrogenic transmission of Trypanosoma evansi infection in camels and its consequences

Trypanosoma evansi infection has started to become a wide spread phenomena around the camel-rearing areas of North Africa and the Middle East. The disease caused by trypanosomes is locally known as “Surra” and it can seriously impact not only the health of domestic animals but the local economy as well. After taking over the management of a farm containing approximately 700 camels, it was found that a large number were suffering from trypanosome infection and it was of the utmost importance to find the source of this infection. An extensive dive into the records and observations were initially made to identify the infected population. Under closer inspection it was found that the infection was limited mostly to female individuals that had undergone extended reproductive analysis or treatment. Blood samples were taken from each of the individuals for buffy coat test and blood smears. Among the total number of tested camels (n = 590), almost 40% were infected with trypanosomes. The number and percentage of infection correlate with the number of fertility and pregnancy treatments that the camels had undergone. The most severely infected group, underwent between 17 and 20 instances of treatment or tests, had an infection rate of almost 90%. The devastating effect of trypanosomiasis on camel pregnancy and birth were also verified with 61% of all abortions and 82% of all neonatal deaths coming from trypanosome infected individuals. These results clearly demonstrate how damaging iatrogenic infections of T. evansi can be and how simply they could have been prevented.

A narrative review on trypanosomiasis and its effect on food production

Trypanosomiasis is an endemic parasitic disease affecting both humans and animal with a severe negative impact on food production in almost all parts of the world. This review seeks to summarize the history of trypanosomiasis and examine the prevalence of trypanosome infection in animals and its effects on food production. A narrative review was conducted on the history of trypanosomiasis. The literature search was conducted on different databases, and selected articles were screened, data extracted, and analyzed. It is believed that trypanosomiasis has been in existence for several decades dating as far as about 2500 BC during the era of the Egyptian kingdom. Africa was found to have the most common cases of animal trypanosomiasis, with 36 out of 40 articles reporting cases. Cattle among other mammals are the most studied animals and they are the most affected. Hence, milk and meat production are greatly affected by trypanosomiasis. The age of animals and the feed provided to animals also played a role in the prevalence and distribution of the pathogen. This review reveals a wide geographical distribution and diverse host range of trypanosome species. The study also highlights the severity of trypanosomiasis and its impact on food production.

A Nanobody/Monoclonal Antibody "hybrid" sandwich technology offers an improved immunoassay strategy for detection of African trypanosome infections.

The scarcity of reliable devices for diagnosis of Animal African trypanosomiasis (AAT) presents a limitation to control of the disease. Existing high-sensitivity technologies such as PCR are costly, laborious, time-consuming, complex, and require skilled personnel. Hence, utilisation of most diagnostics for AAT is impracticable in rural areas, where the disease occurs. A more accessible point-of-care test (POCT) capable of detecting cryptic active infection, without relying on expensive equipment, would facilitate AAT detection. In turn, early management, would reduce disease incidence and severity. Today, several ongoing research projects aim at modifying complex immunoassays into POCTs. In this context, we report the development of an antigen (Ag) detection sandwich ELISA prototype for diagnosis of T. congolense infections, which is comprised of nanobody (Nb) and monoclonal antibody (mAb) reagents. The Nb474H used here, originated from a past study. Briefly, the Nb was engineered starting from mRNA of peripheral blood lymphocytes of an alpaca immunized with soluble lysate of Trypanosoma congolense (TC13). T. congolense glycosomal fructose-1,6-bisphosphate aldolase (TcoALD) was discovered as the cognate Ag of Nb474H. In this study, splenocytes were harvested from a mouse immunized with recombinant TcoALD and fused with NS01 cells to generate a hybridoma library. Random screening of the library on TcoALD retrieved a lone binder, designated IgM8A2. Using Nb474H as Ag-capture reagent in combination with the IgM8A2 monoclonal antibody Ag-detection reagent resulted in a tool that effectively detects native TcoALD released during infection by T. congolense parasites. Hitherto, development of POCT for detection of active trypanosome infection is elusive. The Nanobody/Monoclonal Antibody (Nb/mAb) "hybrid" sandwich technology offers prospects for exploration, using the unique specificity of Nb as a key determinant in Ag capturing, while using the versatility of monoclonal Ab to adapt to various detection conditions.

Evaluation of ITS1 rDNA primers for the detection and identification of African trypanosomes in mammalian hosts and tsetse flies.

Although several primers targeted to the internal transcribed-spacer 1 (ITS1) of the ribosomal DNA (rDNA) have been designed to improve the detection of African trypanosomes, no study tried to compare their agreement level and ability to amplify different trypanosome species in tsetse flies and mammals in various epidemiological settings. This study was designed to fill this gap, by targeting tsetse-infested areas of Cameroon. For this, archived DNA samples reporting at-least one trypanosome species with species-specific PCR primers were reviewed. Ten sets of primers targeting different ITS1 rDNA sequences of trypanosomes were selected for assessment using single-round and nested-PCR method. Amplification rates (sensitivity) and agreement level of different ITS1 assays were compared using Cohen's-Kappa and McNemar's x2 statistic. Little agreement level (k = 0.05–0.52) were observed between different ITS1-primers PCRs detection of African trypanosome species despite significant (X2=54.3, p = 0.0001) high amplification rate 91.6 % (339/370). This sensitivity varied from quite low for T. simiae (11.9 %) and T. vivax (27.3 %) to fairly good for T. congolence (51.9 %), Trypanozoon (32.4 %) and T. theileri (40.3 %). Primers set targeting ITS1-A sequence of trypanosome species recorded the highest sensitivity (50.5 %) with fairly good agreement compared to 39.2 % for ITS1-C (k = 0.52), 32.4 % for ITS1-R (k = 0.47), 29.7 % for ITS1-N (k = 0.48) and 23.0 % for ITS1-KIN (k = 0.43) respectively. This study revealed a diversity in the sensitivity of different trypanosome species with different sets of ITS-primers enhancing the need to use the same sets of primers in different bio-ecological settings. The use of nested-PCR instead of single-round PCR enabled improvement of trypanosome infections detection in both tsetse and mammals. Among the sets of ITS1-primers tested, those designed by to amplify ITS1-A can be considered as the most appropriate for the detection of trypanosome infections in mammals and tsetse flies.

Molecular detection of Anaplasma, Babesia, Theileria, and Trypanosoma infection in cattle and buffaloes in India.

The online version contains supplementary material available at 10.1007/s12639-024-01673-3.

Adipose and skin distribution of African trypanosomes in natural animal infections

BackgroundAnimal 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.MethodsThe 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.ResultsThe 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.ConclusionsThe 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.Graphical

The internal transcribed spacer 1 sequence polymorphism brings updates to tsetse species distribution in the northern Cameroon: Importance in planning efficient vector control.

Vector control remains one of the best strategies to prevent the transmission of trypanosome infections in humans and livestock and, thus, a good way to achieve the elimination of human African trypanosomiasis and animal African trypanosomiasis. A key prerequisite for the success of any vector control strategy is the accurate identification and correct mapping of tsetse species. In this work, we updated the tsetse fly species identification and distribution in many geographical areas in Cameroon. Tsetse flies were captured from six localities in Cameroon, and their species were morphologically identified. Thereafter, DNA was extracted from legs of each tsetse fly and the length polymorphism of internal transcribed spacer-1 (ITS1) region of each fly was investigated using PCR. ITS1 DNA fragments of each tsetse species were sequenced. The sequences obtained were analysed and compared to those available in GenBank. This enabled to confirm/infirm results of the morphologic identification and then, to establish the phylogenetic relationships between tsetse species. Morphologic features allowed to clearly distinguish all the tsetse species captured in the South Region of Cameroon, that is, Glossina palpalis palpalis, G. pallicera, G. caliginea and G. nigrofusca. In the northern area, G. morsitans submorsitans could also be distinguished from G. palpalis palpalis, G. tachinoides and G. fuscipes, but these three later could not be distinguished with routine morphological characters. The ITS1 length polymorphism was high among most of the studied species and allowed to identify the following similar species with a single PCR, that is, G. palpalis palpalis with 241 or 242 bp and G. tachinoides with 221 or 222 bp, G. fuscipes with 236 or 237 bp. We also updated the old distribution of tsetse species in the areas assessed, highlighting the presence of G. palpalis palpalis instead of G. fuscipes in Mbakaou, or in sympatry with G. morsitans submorsitans in Dodeo (northern Cameroon). This study confirms the presence of G. palpalis palpalis in the Adamawa Region of Cameroon. It highlights the limits of using morphological criteria to differentiate some tsetse species. Molecular tools based on the polymorphism of ITS1 of tsetse flies can differentiate tsetse species through a simple PCR before downstream analyses or vector control planning.

The cryo-EM structure of trypanosome 3-methylcrotonyl-CoA carboxylase provides mechanistic and dynamic insights into its enzymatic function

3-Methylcrotonyl-CoA carboxylase (MCC) catalyzes the two-step, biotin-dependent production of 3-methylglutaconyl-CoA, an essential intermediate in leucine catabolism. Given the critical metabolic role of MCC, deficiencies in this enzyme lead to organic aciduria, while its overexpression is linked to tumor development. MCC is a dodecameric enzyme composed of six copies of each α- and β-subunit. We present the cryo-EM structure of the endogenous MCC holoenzyme from Trypanosoma brucei in a non-filamentous state at 2.4Å resolution. Biotin is covalently bound to the biotin carboxyl carrier protein domain of α-subunits and positioned in a non-canonical pocket near the active site of neighboring β-subunit dimers. Moreover, flexibility of key residues at α-subunit interfaces and loops enables pivoting of α-subunit trimers to partly reduce the distance between α- and β-subunit active sites, required for MCC catalysis. Our results provide a structural framework to understand the enzymatic mechanism of eukaryotic MCCs and to assist drug discovery against trypanosome infections.

The Prevalence of Trypanosoma Species in Silver Catfish (Bagrus bajad) from Zobe Reservoir, Dutsin-Ma, Katsina State

This research investigates the prevalence of Trypanosoma species in the silver catfish (Bagrus bajad) population in Zobe Reservoir, Dutsin-Ma, Katsina State. The study aims to provide insights into the parasitic infection rates, identify prevalent Trypanosoma species, and assess its potential impacts on the health and population dynamics of silver catfish in the reservoir. A total of 108 silver catfish samples were collected from Zobe Reservoir in Dutsin-Ma, Katsina, Nigeria at bi-weekly intervals, from July-September; 2023 for the discovery of blood parasites and subjected to thorough parasitological examination. Microscopic analysis, including blood smears and tissue samples, was employed to identify and classify Trypanosoma species. Preliminary findings revealed the presence of Trypanosome infections in the silver catfish population, with a variation in prevalence rates among the sampled specimens. The study identifies specific Trypanosoma species affecting the silver catfish in Zobe Reservoir, shedding light on the diversity and distribution of these parasites in the aquatic ecosystem. The Bagrus bajad obtained according to sex indicates 29 males and 79 females were examined. Females had the highest percentage of infection, 10.12%, while males had the lowest percentage of infection, 3.45%. The results of this research contribute valuable data to the understanding of Trypanosome infections in silver catfish populations, with implications for fisheries management, conservation efforts, and the potential transmission of these parasites to other aquatic organisms. Furthermore, the study underscores the importance of continued monitoring and surveillance to assess the dynamic interactions between Trypanosomes and their fish hosts in freshwater ecosystems.

Usefulness of polymerase chain reaction tests in Chagas disease studies

The Polymerase Chain Reaction (PCR) test is a highly sensitive, specific, and rapid diagnostic tool for Chagas disease. Chagas disease is caused by the protozoan flagellate Trypanosoma cruzi and is endemic to the Americas. While conventional serological methods are still used in the diagnosis of Chagas disease, they are being gradually replaced by molecular methods like PCR. PCR can detect the parasite’s DNA in blood or tissue samples from humans and animals, including asymptomatic infections and animal reservoirs. In a study conducted on a colony of New World monkeys, PCR analysis was found to be superior to conventional screening tools for trypanosome infection, although false negatives can still occur. In clinical studies, PCR has been used to assess the effectiveness of Nifurtimox and Benznidazole in treating acute and chronic Chagas patients. However, the presence of low-grade and intermittent parasitemia in peripheral blood, even in the absence of treatment, renders PCR an unreliable test for evaluating successful treatment. Based on this limiting factor, among others, we do not believe that PCR is an appropriate gold standard test for Chagas in clinical and preclinical studies. Other diagnostic methods, such as serological and biomarker tests, should be used in conjunction with PCR techniques for more accurate diagnosis of Chagas.

Trypanosome Infection in Cattle and Associated Vectors in Etang District of Gambella, Ethiopia.

Bovine trypanosomosis produces significant economic losses due to anemia, loss of body condition, and emaciation. The disease is transmitted biologically by tsetse flies and mechanically by biting flies such as Tabanus and Stomoxys. Therefore, this research is aimed at estimating the prevalence of bovine trypanosomosis and the apparent density of its vectors in the Etang Special District. A cross-sectional study was employed from November 2016 to April 2017 for the prevalence and entomological survey. Trypanosoma species were identified using buffy coat and Giemsa staining techniques. Besides, the entomological surveys were conducted using NGU, pyramidal, biconical, and monoconical traps. The vectors were identified to their genus level based on their morphological features like size, color, wing venation, and proboscis. A total of 457 bovine blood samples were collected and tested, of these 16 (3.50%) animals were positive for trypanosomosis. Similarly, 13 T. vivax (81.25%) and 3 T. congolense (18.75%) were the trypanosome species detected. The prevalence in the young (2.56%) and adult (3.99%) age groups was not statistically significant (P > 0.05). However, there were significant (P < 0.05) differences in prevalence between body condition scores, where poor is 6.31%, medium is 1.30%, and good is 0%. Moreover, the difference in mean PCV values between the parasitemic (20.97) and aparasitemic (28.58) groups was statistically significant (P < 0.05). Glossina flies were not found, although 1756 Tabanus and 52 Stomoxys biting flies were gathered. Accordingly, the overall apparent density of Glossina flies was zero (0), with biting flies (20.54) recorded per trap per day. Moreover, the apparent density of Tabanus and 52 Stomoxys was 39.01 and 1.18, respectively. This study confirmed that trypanosomosis and abundant mechanical vectors continue to be problems in the study area, resulting in cattle productivity losses. As a result, strategic management and prevention methods for trypanosomosis and associated vectors should be prioritized. Further investigation of vector needs to be conducted to clear out tsetse presence.

Molecular detection of Trypanosoma lewisi in rodents distributed in dairy cattle pens and residential areas

The World Organisation for Animal Health continues to be concerned about the spread of atypical human-animal trypanosomiasis. Trypanosoma lewisi is one of the rodent-origin zoonotic trypanosomiasis. Despite the fact that many cases of T. lewisi in humans have been documented in several nations, the study of this pathogenic parasite in Indonesia remains limited. The objective of this investigation was to use a molecular approach to detect T. lewisi in rats captured in livestock pens and residential areas. In Pondok Ranggon Village, Cipayung District, East Jakarta, 14 traps were placed in dairy cattle pens and a total of 50 traps were installed outside and inside houses in Lhoksukon and Ceubrek Villages, Lhoksukon District, North Aceh. The captured rats were identified, sedated, and examined for ectoparasites. The blood of rats was then analysed using Giemsa-stained thin blood films and PCR with TRYP1R and TRYP1S primers. The majority of the Rattus species captured in three locations were R. tanezumi (62.07%), followed by R. norvegicus (6.90%) and R. exulans (3.4%). Xenopsylla cheopis were predominant insect found in the present study (60%), followed by Laelaps echidninus (20%), Laelaps nutalli (12%), and Ornithonyssus bacoti (8%). According to the total flea index, rats captured from cattle pens had fewer fleas than rats from other locations. The molecular analysis revealed that T. lewisi was present in 46.15% of rats captured in human settlements and 66.67% of rats captured in the dairy cattle pens. PCR result also demonstrated that positive T. lewisi found higher in inside house (66.67%) compared to outside house (28.57%). It indicates that trypanosome infections are prevalent in rats from domestic environments and cattle pens, and that R. tanezumi can potentially serve as a source of parasites for both animals and humans through fleas acting as vectors.