Tabanus chrysurus is a potential biological vector of Trypanosoma (Megatrypanum) theileri in Japan

Several species of horse flies (Diptera: Tabanidae) are known as vectors of Trypanosoma (Megatrypanum) theileri and T. theileri-like trypanosomes; these host-parasite relationships were established based on the developmental stages of these parasites discovered in the hindgut of horse flies. T. theileri and T. theileri-like trypanosomes have been detected in cattle and wild deer in Japan; however, the vector horse fly species remains unidentified. Therefore, in this study, we aimed to identify the potential horse fly species serving as vectors of T. theileri in Japan. A total of 176 horse flies were collected between June to September 2020 and 2021 in Tokachi, Hokkaido, Japan. The T. theileri infection in the captured horse flies was determined by PCR and microscopic analyses of their midgut and hindgut. Additionally, the trypanosome, microscopically detected in a horse fly, was molecularly characterized and phylogenetically analyzed using 18S rRNA and partial cathepsin L-like protein gene (CATL) sequence of the trypanosome. The microscopy and PCR analyses revealed 0.57% and 35.8% prevalence of T. theileri in horse flies, respectively. Epimastigote stages of T. theileri, adhered to the hindgut epithelial cells of Tabanus chrysurus via flagella or actively moving in the lumen of the gut, were detected. Phylogenetic analysis revealed the connection of isolated trypanosomes with T. theileri in the TthI clade. These results suggest that Ta. chrysurus is a potential vector of T. theileri.

A Survey on Trypanosoma evansi (Kinetoplastida, Trypanosomatidae) Infection in Domestic Animals in a Surra Endemic Area of Southern Algeria

Background: Trypanosoma (T.) evansi infection is endemic in dromedary camels (Camelus dromedaries) of southern Algeria. Materials and Methods: In order to assess the presence of T. evansi in other domestic animals living together with dromedary camels, a study was conducted in the wilayate of Béchar, El Bayadh, Ouargla and Tamanrasset, between 2015 and 2017. Authorisation to conduct the survey was obtained from the Direction des Services Vétérinaires (DSV, Ministry of Agriculture, Rural Development and Fisheries). A total of 190 animals were sampled, including 42 cattle (Bos taurus), 11 dogs (Canis familiaris), 44 horses (Equus caballus), 3 donkeys (Equus asinus) and 1 mule, 49 goats (Capra hircus) and 40 sheep (Ovis aries). These animals were examined by parasitological (Giemsa stained thin smear, GST), serological (card agglutination test for trypanosomosis (CATT/T. evansi), enzyme-linked immunosorbent assay/Variant Surface Glycoprotein/Rode Trypanozoon antigen type 1.2 [ELISA/VSG RoTat 1.2], immune trypanolysis [TL]) and molecular tests (T. evansi type A specific RoTat 1.2 PCR). Results and Conclusions: The CATT/T. evansi was positive in 10/42 cattle, 0/11 dogs, 2/48 equids, 27/49 goats and 15/40 sheep. On the other hand, 20/38 cattle, 1/9 dogs, 21/42 equids, 17/44 goats and 31/39 sheep were positive in ELISA/VSG RoTat 1.2. However, no single animal was positive in TL. In addition, the T. evansi parasite could not be demonstrated by either GST or RoTat 1.2 PCR in any of the examined animals. This may suggest cross-reactions of CATT/T. evansi and ELISA/VSG RoTat 1.2 with other pathogenic or commensal trypanosome species such as T. vivax or other parasites. Based on these data, in particular taking into account the high specificity of the TL for T. evansi type A, this study does not support the hypothesis that T. evansi circulates in the studied domestic animal species and that they would act as reservoirs for the parasite that causes trypanosomosis in dromedary camels.

Parasitological, Serological and Molecular Prevalence of Trypanosoma evansi among Arabian Camels (Camelus dromedaries) with Evaluation of Antitrypanosomal Drugs

PURPOSE

This study was carried out to assess the prevalence of Trypanosoma evansi infection in naturally diseased Dromedary camels in Dammam, Eastern region of Saudi Arabia. The detection of Trypanosoma evansi was performed using the parasitological, serological, and molecular diagnosis and a comparison between such methods were analyzed. In addition, evaluation of therapeutic efficacy of selected antitrypanosomal drugs, cymelarsan and quinapyrmine (aquin-1.5), was trialed for treatment of diagnosed infected cases.

METHODS

A total 350 randomly selected camels were evaluated using thin blood smear (TBS), RoTat1.2 PCR and CATT/T. evansi techniques.

RESULTS

The total prevalence was 6.9%, 7.7%, and 32.8% by TBS, RoTat1.2 PCR and CATT/T. evansi techniques, respectively. Although PCR detect T. evansi in more samples than TBS, the agreement was good (K = 0.9). Among the CATT/T. evansi results, PCR detect T. evansi in 12 and 15 CATT positive and negative camels, respectively, with low agreement (Kappa = 0.1). The use of cymelarsan and quinapyramine sulfate in the treatment of naturally infected cases demonstrated a very efficient therapeutic response.

CONCLUSION

It was found that 1. Comparing the CATT/T. evansi and PCR results, the positivity of CATT was higher than PCR detection, while the agreement was poor (K = 0.1). 2. Cymelarsan and aquin-1.5 proved to be effective in the treatment of naturally infected camels, but cymelarsan presented with higher effectiveness (100%) than aquin-treated camels (83.3%). a 3. The use of cymelarsan and CATT is recommended for disease treatment and control.

Molecular detection and internal transcribed spacer-1 sequence diversity of Trypanosoma evansi in goats from Cavite, Philippines

Goat production is an important source of livelihood and food. Goats may serve as reservoir of surra affecting livestock production. Here, forty-two free-roaming goats from Cavite, Philippines were screened using two primer sets, Trypanosoma brucei minisatellite chromosome for initial detection and the internal transcribed spacer 1 (ITS-1) to determine phylogeny. Initial PCR detection showed that 19/42 (45%) goats were positive, much higher than the rate previously reported in goats from Cebu (34%). The infectivity rate was higher in male (56%) than in female (42%) and the rate was higher in young ≤1 year old (100%) than in adult >1 year old (43%). Phylogenetic analysis of the ITS-1 sequences between T. evansi goat samples and other isolates indicate potential interspecies transmission.

Detection of anti-Trypanosoma spp. antibodies in cattle from southern Brazil

Bovine trypanosomosis, caused by Trypanosoma vivax, is a disease that originated in Africa and currently affects cattle in several South American countries, including almost all Brazilian states. Despite the reports on T. vivax infection in southern Brazil, data on its circulation status is currently unavailable. In this study, we aimed to detect anti-Trypanosoma spp. IgG antibodies in cattle from Rio Grande do Sul and suggest areas with T. vivax transmission risk. A total of 691 serum samples from cattle in the intermediate regions of Rio Grande do Sul were analyzed using indirect immunofluorescence assay (IFA). The overall seroprevalence of anti-Trypanosoma antibodies in cattle was 24.6% (170/691). The detection rate ranged from 0-37.3%, with a high prevalence in the intermediate regions of Ijuí (37.3%), Uruguaiana (30.7%), and Passo Fundo (28.9%). Thus, these regions were suggested as possible bovine trypanosomosis risk areas due to the high seroprevalence. This is the first serological study to determine Trypanosoma spp. infection status in cattle from Rio Grande do Sul, providing data on the epidemiology of trypanosomosis in the state.

Trypanosome diversity in small mammals in Uganda and the spread of Trypanosoma lewisi to native species

Uganda's diverse small mammalian fauna thrives due to its rich habitat diversity, which hosts a wide range of blood parasites, including trypanosomes, particularly the subgenus Herpetosoma typical for rodent hosts. We screened a total of 711 small mammals from various habitats for trypanosomes, with 253 microscopically examined blood smears and 458 tissue samples tested by nested PCR of the 18S rRNA gene. Of 51 rodent and 12 shrew species tested, microscopic screening reaches 7% overall prevalence (with four rodent species positive out of 15 and none of the shrew species out of four), while nested PCR indicated a prevalence of 13% (17 rodent and five shrew species positive out of 49 and 10, respectively). We identified 27 genotypes representing 11 trypanosome species, of which the majority (24 genotypes/9 species) belong to the Herpetosoma subgenus. Among these, we detected 15 new genotypes and two putative new species, labeled AF24 (found in Lophuromys woosnami) and AF25 (in Graphiurus murinus). Our finding of three new genotypes of the previously detected species AF01 belonging to the subgenus Ornithotrypanum in two Grammomys species and Oenomys hypoxanthus clearly indicates the consistent occurrence of this avian trypanosome in African small mammals. Additionally, in Aethomys hindei, we detected the putative new species of the subgenus Aneza. Within the T. lewisi subclade, we detected eleven genotypes, including six new; however, only the genotype AF05b from Mus and Rattus represents the invasive T. lewisi. Our study has improved our understanding of trypanosome diversity in African small mammals. The detection of T. lewisi in native small mammals expands the range of host species and highlighting the need for a broader approach to the epidemiology of T. lewisi.

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

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

Molecular and genetic diversity in isolates of Trypanosoma evansi from naturally infected horse and dogs by using RoTat 1.2 VSG gene in Madhya Pradesh, India

BACKGROUND

Trypanosoma evansi is a protozoan parasite that can infect a wide range of animals and is widespread around the world. In this study, we analyzed four fatal cases of T. evansi infection using clinical, parasitological, and molecular approaches. We also explored the genetic diversity, demographic history, and population-genetic structure of T. evansi using available Rode Trypanozoon antigenic type (RoTat) 1.2 gene sequences.

METHODS AND RESULTS

Clinical findings of infected animals revealed high fever, anemia, weakness, and anorexia. The animals were treated with diminazene aceturate, which was moderately effective, and hematobiochemical parameters showed changes in hemoglobin and glucose levels. The molecular and genetic diversity of T. evansi was analyzed using the RoTat 1.2 VSG gene. Phylogenetic and haplotype analysis revealed two distinct clusters of T. evansi circulating in India. The genetic diversity indices, neutrality tests, gene flow, and genetic differentiation outcomes confirmed the genetic diversity of the T. evansi population, with a lack of uniformity. The identification of two distinct clusters, exhibiting differential demographic histories and evolutionary forces, implies that the clusters may have undergone independent evolutionary trajectories or experienced different environmental pressures.

CONCLUSION

The present findings underlined the need of an early and precise diagnosis in order to treat and control T. evansi infections, and the RoTat 1.2 VSG gene is an important genetic marker for understanding the genetic diversity and evolutionary history of T. evansi. This knowledge can be used to create tailored strategies to control and manage the infection in an endemic region.

Molecular and hematological investigation of Trypanosoma evansi infection in Iranian one-humped camels (Camelus dromedarius)

Trypanosoma species cause animal trypanosomiasis that infects many animals. Trypanosoma evansi is an organism that infects camels. There are many economic problems associated with this disease, including lower milk and meat yields and abortions. The purpose of the current survey was molecular study of the presence of Trypanosoma in dromedary camel blood in the south of Iran, and its effects on the hematologic, and some acute-phase protein changes. Blood samples were aseptically collected from the jugular vein of dromedary camels (n = 100; aged from 1 to 6 years) originating from Fars Province in EDTA-coated vacutainers. Genomic DNA from 100 µL of the whole blood was extracted and amplified using a PCR assay based on ITS1, 5.8S, and ITS2 ribosomal regions. Also, the PCR products obtained were sequenced. Moreover, the changes in hematological parameters and serum acute-phase proteins (serum amyloid A, alpha-1 acid glycoprotein, and haptoglobin) were measured. Among 100 tested blood, nine samples (9%, 95% CI: 4.2-16.4%) were found positive by the PCR assay. The phylogenetic tree and blast analysis showed four different genotypes closely related to the strains (accession numbers: JN896754 and JN896755) previously reported from dromedary camels in Yazd Province, center Iran. Based on hematological analysis, normocytic and normochromic anemia and lymphocytosis were detected in the PCR-positive cases compared with the negative group. Furthermore, alpha-1 acid glycoprotein was significantly increased in the positive cases. There was a substantial and positive relation between the number of lymphocytes, and the levels of alpha-1 acid glycoprotein and serum amyloid A in the blood (p = 0.045, r = 0.223 and p = 0.036, r = 0.234, respectively). A noticeable frequency of T. evansi infection was reported in dromedary camels in south Iran. This is the first report on the genetic diversity of T. evansi in this region. There was a significant association among Trypanosoma infection, lymphocytosis, and alpha-1 acid glycoprotein. Trypanosoma-positive camels had a significant decrease in hematocrit (HCT), hemoglobin (Hb), and red blood cell (RBC) values compared to the non-infected group. Further experimental studies are needed to elucidate the hematological and acute-phase protein alteration during a different phase of Trypanosoma spp. infection.

Molecular Detection of Animal Trypanosomes in Different Animal Species in the Visayas Region of the Philippines

PURPOSE

Animal trypanosomosis is one of the most important parasitic diseases significantly affecting the Philippine economy. It is considered by the government to be the second most important disease of livestock after fasciolosis. A PCR-based molecular survey for trypanosomes in different animals in Bohol, Philippines, was performed to assess the prevalence of trypanosomosis in the area during the rainy and dry season.

METHODS

A total of 269 blood samples were collected in two batches in rainy and dry season from different animal species in Ubay Stock Farm in Ubay, Bohol, the Philippines, including 151 samples from water buffaloes, 76 samples from cattle, 35 samples from goats, and 7 samples from horses. DNA was subsequently extracted from these blood samples, and two different PCR assays were employed to detect and identify trypanosomes DNA including ITS1 PCR and CatL PCR.

RESULTS

Animal trypanosomes, Trypanosoma evansi and Trypanosoma theileri, were detected in water buffalo (37.7%) [95%CI: 30.4 - 45.7], cattle (44.7%) [95%CI: 34.1 - 55.9], and goats (34.3%) [95%CI: 20.8 - 50.8]. Only T. evansi was detected in horses (28.6%) [95% CI: 8.2 - 64.1]. No clinical signs were observed in all positive animals.

CONCLUSION

This highlights the importance of domestic animals that can be infected with no signs but may act as reservoir animals and transmit trypanosomosis to susceptible animals. This study supports the importance of regular surveillance to estimate the prevalence of the disease, emphasizing its various dynamics in the affected areas and supporting efficient intervention measures.

Genotyping of Trypanosoma brucei evansi in Egyptian camels: detection of a different non-RoTat 1.2 Trypanosoma brucei evansi in Egyptian camels

Trypanosoma brucei evansi (T. b. evansi) is an enzootic organism found in Egyptian camels, which genetically classified into types A and B. To detect the parasite genotype circulating in Egyptian camels, we collected 94 blood samples from three distant districts and subjected them to different PCR assays; T. brucei repeat (TBR), internal transcribed spacer-1 (ITS-1), and variable surface glycoproteins (VSG) (RoTat 1. 2, JN 2118Hu) and EVAB PCRs. The highest prevalence was obtained with TBR (80/91; 87.9%), followed by ITS-1 (52/91; 57.1%), VSG JN 2118Hu (42/91; 46.2%), and VSG RoTat 1. 2 (34/91; 37.4%). We reported a different non-RoTat 1. 2 T. b. evansi for the first time in Egyptian camels. Results showed that 47 (58.7%) out of 80 samples were classified as T. b. evansi. Of these, 14 (29.8%) were RoTat 1. 2 type, 13 (27.6%) were non-RoTat 1. 2 type, and 20 (42.6%) samples were from mixed infection with both types. All samples were tested negative with EVAB PCR. RoTat 1. 2 T. b. evansi was the most prevalent in Giza and El Nubariyah, whereas, in Aswan, the only type detected was non-RoTat 1. 2 T. b. evansi. The nucleotide sequences of the VSG RoTat 1.2 and JN 2118Hu PCR products were submitted to DNA Data Bank of Japan (DDBJ) and GenBank under the accession numbers LC738852, and (OP800400-OP800403). Further research is required to increase the sample size and verify the new sequences to corroborate the prevalence of a new variant of non-RoTat 1.2 T. b. evansi in Egypt.

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

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

Trypanosoma lewisi in blood of Rattus rattus complex residing in human settlements, Nakhon Si Thammarat, Thailand: Microscopic and molecular investigations

Trypanosomes are blood parasites infected in various mammals, including rats. The presence of rats in human settlements can increase the chance of Trypanosoma transmission to humans. The molecular study of multispacer in Trypanosoma spp. in naturally infected rodents in Thailand is scanty. The objective of this study was to detect Trypanosoma in the blood of the captured rats in Nakhon Si Thammarat, Thailand, using microscopic and molecular techniques. This was a cross-sectional study conducted in human settlement areas. Ninety-nine blood samples were collected using cardiac puncture. A blood sample was smeared on a glass slide and examined using a compound light microscope and a scanning electron microscope. Moreover, polymerase chain reaction was applied to detect Trypanosoma evansi and T. lewisi in the blood. An additional primer set was used to confirm the species of the detected trypanosome. Approximately 18% of the rats had positive Trypanosoma infections. All Trypanosoma-positive blood samples were matched with sequences of T. lewisi. The stumpy form of trypanosome had higher nucleus related parameters than the slender form. Interestingly, the partial sequences of the alpha-tubulin gene of T. lewisi were first reported in the naturally infected RrC in this study. Based on the results obtained, T. lewisi biology, particularly the virulent components and route of transmission, pathogenesis, and in vitro experiments, are strongly recommended for further study.

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

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

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

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

Molecular detection and therapeutic study of Trypanosoma brucei evansi from naturally infected horses in Punjab, Pakistan

Trypanosomiasis is one of the severe pathogenic infections, caused by several Trypanosoma species, affecting both animals and humans, causing substantial economic losses and severe illness. The objective of this study was to determine the molecular diagnosis and the risk factors associated with trypanosomiasis in District Jhang, Punjab, Pakistan. For this purpose, blood samples were randomly collected from 200 horses. A predesigned questionnaire was used to collect data on risk factors before the sample collection. The microscopy examination through Giemsa staining, formol gel test and PCR techniques were used to find the prevalence. The prevalence was recorded as 22.5% with microscopy examination, 21% through formol gel test and 15.5% with PCR based results. Analysis of risk factors associated with Trypanosoma brucei evansi occurrence was carried out using Chi-square test. It showed the prevalence of Trypanosoma brucei evansi was significantly (p⟨0.05) associated with sex, age, rearing purpose and body condition whereas non-significantly (p⟩0.05) with insects control practices. This study supports the idea that PCR is a sensitive, robust and more reliable technique to diagnose trypanosomiasis. It was concluded that Trypanosoma brucei evansi is widely prevalent in Jhang (Pakistan), highlighting a dire need to develop control strategies and education programmes to control this disease in developing countries.

Analysis of the epidemiological variables associated with a high prevalence of bovine surra in the Chhattisgarh state of India

Trypanosoma evansi, a unicellular haemoflagellate, causes surra in bovines and other economically important livestock species. We report here the epidemiological variables associated with the high prevalence of T. evansi infection in cattle in the plain agro-climatic zone of Chhattisgarh state, India. A total of 920 blood and sera samples were tested by a combination of parasitological, molecular and serodiagnostic tests. An overall prevalence of T. evansi was recorded as 4.57% (95% CI: 3.22-5.92%), 6.09% (95% CI: 4.54-7.63%), 63.91% (95% CI: 60.81-67.01%) and 55.33% (95% CI: 52.12-58.54%) by direct microscopy, PCR, ELISA and IFAT, respectively. The Chi-Square test established a significant correlation between the prevalence of T. evansi and the season, breed and place of the study, while the association with the gender and age of the animals was insignificant. The analysis of the prevalence ratio revealed a significant association of the breed, season and place of study with the prevalence of T. evansi. As per PR _observed, the prevalence was 1.63 times higher in summer and 1.68 times higher in the rainy season than in the winter (reference season). The prevalence was higher in all the districts as compared to Rajnandgaon (reference district). The prevalence ratio in Sahiwal and HF cross-breed cattle was significantly higher than the Gir breed of cattle (reference). Durg district recorded the highest prevalence of surra, and the difference was significant. The medium IFAT titre, determined in a large number of sera collected from Durg, predicted a higher incidence of trypanosomosis in that district. Since T. evansi has a broad host range, the study predicted that a large population of livestock in Chhattisgarh state were at high risk of T. evansi infection. Treatment of the subclinically and clinically infected animals with selective curative drugs, such as diminazene aceturate, isometamidium chloride or the combination of quinapyramine sulphate and quinapyramine chloride, could help restore productivity and help in containing the infection.

Silent Trypanosoma evansi infection in humans from India revealed by serological and molecular surveys, and characterized by variable surface glycoprotein gene sequences

BACKGROUND

The importance of emerging atypical human trypanosomosis is gaining momentum due to increasing detection and its possible impact on human health. A cross sectional study of atypical human trypanosomosis due to Trypanosoma evansi was carried out in Kolkata and Canning area of West Bengal state of India where previously a death was reported.

METHODS

In this study blood and serum samples from 173 individuals were collected during August to December 2014. To check the presence of antibodies against T. evansi, card agglutination test and for the presence of T. evansi specific DNA, PCR were conducted.

RESULTS

T. evansi infection was identified in 5.2% (9/173) human blood samples by CATT serological test (Card agglutination test for trypanosomosis). PCR targeting VSG gene sequences suggested active T. evansi infection in 2.89% (5/173). VSG gene sequences herein determined for five isolates from human cases shared high similarity (89.4-100%). Phylogenetic inference clustered the human isolates with other isolates from different host species from India and other countries, forming a clade exclusive of Indian isolates (84.0 to 100% sequence similarity).

CONCLUSION

First report of symptomless human T. evansi infection detected by combined serological and PCR assays. First phylogenetic analysis of VSG gene sequences including human isolates of T. evansi in which Indian isolates of T. evansi from human and other hosts clustered in a single clade.

A 5-Year Prospective Study on Incidence and Clinico-pathological Changes Associated with Naturally Occurring Trypanosomosis in Dogs of Mizoram, India

PURPOSE

The present research was taken to study the hospital-based incidence and clinico-pathological changes associated with naturally occurring trypanosomosis in dogs of Mizoram.

METHODS

A 5-year prospective study on hospital-based incidence and clinico-pathological changes associated with naturally occurring trypanosomosis in dogs of Mizoram was carried out during the study period from April, 2015 to March, 2020. Trypanosoma evansi infection was confirmed by microscopic examination and polymerase chain reaction (PCR). Non-infected clinically healthy dogs (n = 6) served as control. Blood samples were collected to study the haemogram and serum samples were used for the evaluation of serum biochemical parameters and oxidant-antioxidant parameters.

RESULTS

During the study period, an overall incidence of 0.25% was recorded for trypanosomosis in dogs. The most consistent clinical findings noticed were anorexia/inappetence, pyrexia, depression/lethargy, pale mucous membrane, dehydration and lymphadenomegaly. Anaemia, granulocytopenia, lymphocytosis and thrombocytopenia were the major findings noticed in trypanosomosis affected dogs. The profile of vital organ function revealed that the mean values of total protein, albumin and random blood glucose were significantly (P < 0.05) lower, whereas the mean values of alanine aminotransferase (ALT), aspartate aminotransferase (AST), alkaline phosphatase (ALP), total bilirubin, blood urea nitrogen (BUN) and creatinine were significantly (P < 0.05) higher in dogs affected with trypanosomosis. The mean value of lipid hydroperoxide (LPO) was significantly (P < 0.05) higher, whereas the mean values of glutathione (GSH), superoxide dismutase (SOD) and total antioxidant activity (TAOA) were significantly (P < 0.05) lower in trypanosomosis affected dogs. When total erythrocyte count (TEC) was correlated with LPO (r = - 0.631, P < 0.05), a negative correlation was found, while in case of GSH (r = 0.757, P < 0.05), SOD (r = 0.767, P < 0.05) and TAOA (r = 0.713, P < 0.05), it was positively correlated.

CONCLUSION

A negative correlation of TEC count with LPO, while a positive correlation with GSH, SOD and TAOA signify the role of oxidative stress in the pathogenesis of anaemia induced by T. evansi infection in dogs. The present study findings might be helpful to clinicians when treating clinical cases of this kind. Incorporation of organ protective drugs and antioxidants in the treatment schedule may result in better prognosis.

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

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

First molecular survey of animal trypanosomes in Paraguayan horses

Despite the epidemic situation of animal trypanosomosis caused by Trypanosoma evansi, Trypanosoma equiperdum and Trypanosoma vivax in South American countries, there are no reports for the prevalence of animal trypanosomes in Paraguay. In this study, 408 blood samples were obtained from apparently healthy horses from sixteen departments of Paraguay, for routine medical check-up from August to September 2019, and a polymerase chain reaction (PCR)-based cross-sectional study was carried out to identify trypanosome prevalence. The prevalence of Trypanozoon (T. evansi and T. equiperdum) and T. vivax was 7.11% (29/408) and 26.23% (107/408), respectively. Mixed infections were detected in 4.90% (20/408) of the samples. Some of the selected trypanosome positive samples were confirmed as T. vivax and T. evansi Type A by sequence analysis of the internal transcribe spacer region and RoTat1.2 variant surface glycoprotein gene, respectively. In conclusion, we found higher prevalence of T. vivax than Trypanozoon in Paraguayan horses. However, the genotypic variation should be verified in further studies.

Associative Genetic Diversity of RoTat 1.2 VSG in Different Trypanosoma evansi Isolates

BACKGROUND

Numerous phylogenetic markers have been tested over a period of time for delineating evolutionary history of haemoflagellate-Trypanosoma evansi.

PURPOSE

To find out the associative genetic diversity, within the various isolates of T. evansi across the globe, based on RoTat 1.2 VSG gene.

METHODS

A total of 5 equine isolates of T. evansi from Northern India were characterized. PCR products were sequenced and sequences were compared with available sequences across India and world. Phylogenetic tree was constructed based on maximum parsimony (MP) method with the tree-bisection-regrafting (TBR) algorithm.

RESULTS

Indian isolates formed multiple clades with two haplotypes. The present isolates showed 99.49-100.00% nucleotide homology within themselves. On broader line, Indian isolates were found to be closer to Egyptian isolates than the African counterparts. Few of the Indian isolates showed marked resemblance with a particular Egyptian isolate than with their Indian counter parts. Another remarkable finding is the close association of equine isolates from India with other equine isolates and their clear divergence from isolates of T. evansi affecting other hosts from India and abroad.

CONCLUSION

Vast genetic divergence was seen between the isolates suggesting of multiple distinct lineages of T. evansi amongst the Indian livestock. Interestingly, variations in sequences were seen based on the host range of isolates. The findings are very important from molecular evolutionary point of view.

New Haplotypes of Trypanosoma evansi Identified in Dromedary Camels from Algeria

PURPOSE

Surra is a zoonotic disease caused by Trypanosoma evansi (Trypanozoon), a salivary trypanosome native to Africa which affects a wide range of mammals worldwide and causes mortality and significant economic loss. The present study was devoted to the molecular characterization of T. evansi derived from naturally infected dromedary camels in Algeria.

METHODS

A total of 148 blood samples were collected from mixed age camels living in one of four geographic regions (Ouargla, El Oued, Biskra and Ghardaia) of Algeria. Samples underwent PCR amplification and sequencing of the internal transcribed spacer 1 (ITS1) complete sequence.

RESULTS

DNA of Trypanosoma spp. was found in 19 camels (12.84%). Trypanosoma spp. molecular positivity was not affected by sex (p = 0.50), age (p = 0.08), or geographic location (p = 0.12). Based on multiple sequence alignment of the obtained DNA sequences with representative T. evansi ITS1 sequences available globally, the Algerian sequences were grouped within four different haplotypes including two which were original.

CONCLUSION

Results of this study provide preliminary data on which future studies of genetic diversity and molecular epidemiology of T. evansi can be based.

Native and Introduced Trypanosome Parasites in Endemic and Introduced Murine Rodents of Sulawesi

The Indonesian island of Sulawesi is a globally significant biodiversity hotspot with substantial undescribed biota, particularly blood-borne parasites of endemic wildlife. Documenting the blood parasites of Sulawesi's murine rodents is the first fundamental step towards the discovery of pathogens likely to be of concern for the health and conservation of Sulawesi's endemic murines. We screened liver samples from 441 specimens belonging to 20 different species of murine rodents from 2 mountain ranges on Sulawesi, using polymerase chin reaction (PCR) primers targeting the conserved 18S rDNA region across the protozoan class Kinetoplastea. We detected infections in 156 specimens (10 host species) with a mean prevalence of 35.4% (95% confidence interval [CI] = 30.9-39.8%). Sequences from these samples identified 4 infections to the genus Parabodo, 1 to Blechomonas, and the remaining 151 to the genus Trypanosoma. Within Trypanosoma, we recovered 17 haplotypes nested within the Trypanosoma theileri clade infecting 117 specimens (8 host species) and 4 haplotypes nested within the Trypanosoma lewisi clade infecting 34 specimens (6 host species). Haplotypes within the T. theileri clade were related to regional Indo-Australian endemic trypanosomes, displayed geographic structuring but with evidence of long-term connectivity between mountains, and had substantial phylogenetic diversity. These results suggest T. theileri clade parasites are native to Sulawesi. Conversely, T. lewisi clade haplotypes were recovered from both endemic and introduced rodents, demonstrated complete geographic separation between clades, and had low genetic diversity. These results suggest that the T. lewisi clade parasites invaded Sulawesi recently and likely in 2 separate invasion events. Our results provide the first records of metakinetoplastids in Sulawesi's rodents and highlight the need for more extensive sampling for pathogens in this biodiversity hotspot.

Molecular identification of trypanosomes in cattle in Malawi using PCR methods and nanopore sequencing: epidemiological implications for the control of human and animal trypanosomiases

This study aimed to identify trypanosomes infecting cattle in Malawi in order to understand the importance of cattle in the transmission dynamics of Human African Trypanosomiasis (HAT) and Animal African Trypanosomosis (AAT). A total of 446 DNA samples from cattle blood from three regions of Malawi were screened for African trypanosomes by ITS1 PCR. The obtained amplicons were sequenced using a portable next-generation sequencer, MinION, for validation. Comparison of the results from ITS1 PCR and MinION sequencing showed that combining the two methods provided more accurate species identification than ITS1 PCR alone. Further PCR screening targeting the serum resistance-associated (SRA) gene was conducted to detect Trypanosoma brucei rhodesiense. Trypanosoma congolense was the most prevalent Trypanosoma sp., which was found in Nkhotakota (10.8%; 20 of 185), followed by Kasungu (2.5%; 5 of 199). Of note, the prevalence of T. b. rhodesiense detected by SRA PCR was high in Kasungu and Nkhotakota showing 9.5% (19 of 199) and 2.7% (5 of 185), respectively. We report the presence of animal African trypanosomes and T. b. rhodesiense from cattle at the human-livestock-wildlife interface for the first time in Malawi. Our results confirmed that animal trypanosomes are important causes of anemia in cattle and that cattle are potential reservoirs for human African trypanosomiasis in Malawi.

Evidence of natural infections with Trypanosoma, Anaplasma and Babesia spp. in military livestock from Tunisia

Livestock constitute habitual hosts and carriers for several infectious pathogens which may represent a serious public health concern affecting the readiness of military forces and lead to wide economic losses. The present report aimed to investigate the prevalence of some haemopathogens infecting military livestock, particularly, dromedaries, sheep and horses using Giemsa-stained blood smears. A total of 300 animals (100 from each species) were selected, clinically examined and sampled. Trypanosoma spp. (22.0%), Anaplasma spp. (17.0%) and Babesia spp. (1.0%) were identified in camels' blood. Six dromedaries were found to be co-infected by Trypanosoma and Anaplasma organisms (6.0%). Camels of female gender, infested by ticks and showing clinical signs were statistically more infected by Trypanosoma spp., compared to those of male gender, free of ticks and apparently healthy (P= 0.027, 0.000 and 0.004, respectively). Babesia spp. infection (1.0%) was identified, for the first time in Tunisia, in one adult female camel that presented abortion and anemia. Anaplasma spp. was the only haemopathogen identified in examined sheep (6.0%) and horses (17.0%). Horses infested by Hippobosca equina flies and sheep infested by Rhipicephalus turanicus ticks were more infected by Anaplasma spp. than other non-infested animals (P=0.046 and 0.042, respectively). Hyalomma dromedarii, H. impeltatum and H. excavatum were the most prevalent diagnosed ticks removed from camels with an intensity of infestation of 1.2 ticks per animal. However, in sheep, only R. turanicus was identified. H. equina and Tabanus spp. were the potential hematophagous flies found in dromedaries and horses herds. This useful data must be taken into consideration during animal treatment and vectors' control programs in Tunisian military farms which help to limit the diffusion of vector-borne diseases, keep our livestock healthy and reduce economic losses.

Trypanocidal drug resistance: A threat to animal health and production in Gidami district of Kellem Wollega Zone, Oromia Regional State, Western Ethiopia

This study was conducted from May 08 to June 08, 2017 in Gidami District, Kellem Wollega Zone, Oromia Regional State, Ethiopia. The objective of the study was to assess the occurrence of trypanocidal drug resistance in naturally infected cattle in identified hot spots villages of Gidami district. An initial cross-sectional prevalence study was conducted in seven villages from November 2015 to June 2016. Based on the outcome of the cross-sectional study, Kellem and Gry Sonka villages with highest trypanosome prevalence (28% and 30.85%) respectively were selected. An abbreviated 28-day field prototocol study was used to estimate resistance to 1 mg/kg bw isometamidium chloride (ISM) and 7.0 mg/kg bw diminanzene aceturate (DA). In this study, 100 purposively selected trypanosome positive cattle were ear-tagged and allocated into two treatment groups: a group I were treated with 2% solution of 1 mg/kg bw ISM and a group II were treated with 7% solution of 7 mg/kg bw DA. The treatment day was considered as day 0 and the treated cattle were monitored for trypanosomes and packed cell volume (PCV) levels on days 14 (for DA and ISM) and 28 (for ISM) post treatment. A treatment failure rate of 25% of the cattle in the ISM treated group on days 14 and 28 were indicative of resistance, whereas in the DA treated group the response was assessed only on day 14 post-treatment. The results of the study confirmed the presence of drug resistance to the maximum recommended doses of ISM and DA in Giray Sonka and Kellem villages of Gidami district. Out of 50 trypanosome positive cattle treated with ISM, 68% had persistent infections on day 28 post-treatment. Similarly, of the 50 trypanosome positive cattle treated with 7 mg/kg bw DA, 36% had persistent trypanosomes on day 14 post treatment. Of all ISM and DA treatment failures T. congolense accounted for (70.59%; 66.67%), T. vivax (23.53%; 27.78%) and T. brucei (5.88%; 5.55%) respectively. Drug resistance has indeed been a considerable threat in all villages of Gidami district, but the situation is magnified in Giray Sonka and Kellem villages. Thus, an integrated control approach of trypanosomosis should be conducted to ensure sustainable animal health and production in the area. In addition beside tsetse control, rational use of trypanocidal drugs and control of co-infections to exploit self-cure against resistant trypanosome populations are recommended. Furthermore, extensive data on trypanocidal drug sensitivity tests using advanced molecular techniques considered as elucidative.

Safety and efficacy of three trypanocides in confirmed field cases of trypanosomiasis in working equines in The Gambia: a prospective, randomised, non-inferiority trial

Background

Globally, working equines have a continued and growing socioeconomic role in supporting the livelihoods of between 300–600 million people in low income countries which is rarely recognised at a national or international level. Infectious diseases have significant impact on welfare and productivity in this population and equine trypanosomiasis is a priority disease due to its severity and prevalence. Strategies are required to improve the prevention, diagnosis, management and treatment of trypanosomiasis in equines and more data are required on the efficacy and safety of current trypanocidal drugs.

Methods

A prospective randomised, open-label non-inferiority trial was performed in The Gambia on horses and donkeys that fulfilled 2/5 clinical inclusion criteria (anaemia, poor body condition, pyrexia, history of abortion, oedema). Following randomised trypanocidal treatment (diminazene diaceturate, melarsomine dihydrochloride or isometamidium chloride), animals were observed for immediate adverse drug reactions and follow-up assessment was performed at 1 and 2 weeks. Blood samples underwent PCR analysis with specific Trypanosoma sp. primers. Treatment efficacy was assessed by measuring changes in clinical parameters, clinicopathological results and PCR-status post-treatment after evaluating for bias. Using PCR status as the outcome variable, non-inferiority of isometamidium treatment was determined if the upper bound limit of a 2-sided 95% CI was less than 10%.

Results

There was a significant beneficial effect upon the Trypanosoma sp. PCR positive population following trypanocidal treatment for all groups. The findings of clinical evaluation and PCR status supported a superior treatment effect for isometamidium. Melarsomine dihydrochloride efficacy was inferior to isometamidium. There were immediate, self-limiting side effects to isometamidium in donkeys (26%). Diminazene had the longest duration of action as judged by PCR status.

Conclusions

The data support the continued use of isometamidium following careful dose titration in donkeys and diminazene for trypanosomiasis in equines using the doses and routes of administration reported.

Equine trypanosomiasis is endemic in many areas of the world with high morbidity and mortality in affected populations. Trypanocides form an essential part of current treatment strategies but evidence regarding efficacy in equines is scarce. In order to inform disease management, the efficacy of three trypanocidal drugs was assessed in horses and donkeys that fulfilled 2/5 clinical inclusion criteria for trypanosomiasis in The Gambia. Selected equines received randomised treatment with either isometamidium, diminazene or melarsomine dihydrochloride and were observed for adverse drug reactions. Follow-up was performed at 1 and 2 weeks. Blood collected at each timepoint was analysed for Trypanosoma spp. using a PCR approach. Within the selected population 66% were PCR positive pre-treatment for Trypanosoma spp.. Trypanosome positive individuals responded favourably to each treatment, but clinical evaluation and PCR status post-treatment supported a superior effect for isometamidium. Melarsomine dihydrochloride had inferior efficacy to isometamidium. Immediate adverse side effects were only documented following isometamidium administration in donkeys (26%) and these were self-limiting. Diminazene had the longest duration of action as judged by PCR status. The data support the continued use of isometamidium and diminazene but not melarsomine dihydrochloride for trypanosomiasis in equines at the doses and routes of administration reported.

Systematic review and meta-analysis on the global distribution, host range, and prevalence of Trypanosoma evansi

BACKGROUND

Surra is an animal trypanosomosis, caused by infection with Trypanosoma evansi and leading to severe economic loss due to mortality and morbidity. Compared to tsetse-transmitted animal trypanosomoses, little attention is given to the epidemiology and control of surra. Understanding its epidemiology is a first step in local and global efforts to control the disease. We conducted a systematic review and meta-analysis of published studies on distribution, host ranges and prevalence of T. evansi infection.

METHODS

Four electronic databases were searched for publications on T. evansi that met our inclusion criteria for the systematic review. Subsets of publications were subjected to meta-analysis for the pooled prevalence of T. evansi in various hosts as determined by multiple detection methods.

RESULTS

A total of 272 references published between 1906-2017 were included. Trypanosoma evansi was reported from 48 countries; largely confined to Africa and Asia with publications on natural T. evansi infections from 77% (n = 48) of countries, contrasting with seven countries in South America, and four in Europe where T. evansi is not endemic but was imported with infected animals. Although surra is a notifiable disease, many countries do not report surra cases to OIE. Trypanosoma evansi was mainly reported from dromedary camels in Africa and the Middle East, water buffaloes, cattle, dogs and horses in East and Southeast Asia. In South America, the acute form of the disease was reported in horses and dogs. Surra was also reported in a wide range of wild animals. Some rare human cases occurred in India and Vietnam. Meta-analysis on a subset of 165 publications indicated pooled prevalence of T. evansi in domestic animals ranging from 14-31%, 6-28% and 2-9% using respectively antibody detection, molecular and parasitological tests, with camels as the most affected, followed by buffalo and cattle.

CONCLUSIONS

This study illustrates that T. evansi affects a wide range of domestic and wild animals in Africa, Asia and South America with highest prevalence observed in dromedary camels. For successful control of T. evansi, both locally and globally, the role of wild animals in the epidemiology of surra needs further investigation.

Molecular detection of equine trypanosomiasis in the Riyadh Province of Saudi Arabia

We conducted a cross-sectional study to detect trypanosome infections of horses and donkeys in the Riyadh Province of Saudi Arabia. DNA was extracted from blood samples collected from 368 horses and 142 donkeys, and subjected to universal first ribosomal internal transcribed spacer region (ITS1)-PCR followed by Trypanosoma evansi species-specific RoTat1.2-PCR. The universal ITS1-PCR revealed T. evansi infection in horses ( n = 12; 3.3%) and donkeys ( n = 4; 2.8%). There was no significant effect of sex or age on the prevalence of trypanosomiasis in horses or donkeys. Application of the RoTat1.2-PCR revealed that the RoTat1.2 VSG gene was absent from the positive ITS1-PCR samples of 3 horses and 1 donkey. This discrepancy could be explained by the circulation of T. evansi type B in Saudi Arabia; however, this suspicion requires confirmation.

Integrative taxonomic approach of trypanosomes in the blood of rodents and soricids in Asian countries, with the description of three new species

Trypanosoma lewisi (Kinetoplastea: Trypanosomatida: Trypanosomatidae) with a cosmopolitan distribution is the type species of the subgenus Herpetosoma, which includes ca. 50 nominal species isolated mainly from rodents. Since members of Herpetosoma in different host species have an almost identical morphology of bloodstream forms, these trypanosomes are referred to as 'T. lewisi-like', and the molecular genetic characterization of each species is necessary to verify their taxonomy. In the present study, we collected blood samples from 89 murid rodents of 15 species and 11 soricids of four species in Indonesia, Philippines, Vietnam, Taiwan, and mainland China for the detection of hemoprotozoan infection. T. lewisi and T. lewisi-like trypanosomes were found in the blood smears of 10 murid animals, which included Bandicota indica (two rats), Rattus argentiventer (one rat), and Rattus tiomanicus (two rats) in Indonesia; Rattus rattus (one rat) in the Philippines; and Niviventer confucianus (four rats) in mainland China. Furthermore, large- or medium-sized non-T. lewisi-like trypanosomes were detected in two soricids, Crocidura dracula in Vietnam and Anourosorex yamashinai in Taiwan, respectively. Molecular genetic characterization of the small subunit (SSU) ribosomal RNA gene (rDNA) and glycosomal glyceraldehyde-3-phosphate dehydrogenase (gGAPDH) gene indicated that the trypanosomes from all the murid hosts had identical SSU rDNA or gGAPDH gene nucleotide sequences except for those in N. confucianus in mainland China. These N. confucianus-infecting trypanosomes also showed several unique morphological features such as smaller bodies, anteriorly positioned nuclei, and larger rod-shaped kinetoplasts when compared with T. lewisi trypomastigotes. Trypanosoma (Herpetosoma) niviventerae n. sp. is erected for this new species. Similarly, based on morphological and molecular genetic characterization, Trypanosoma sapaensis n. sp. and Trypanosoma anourosoricis n. sp. are proposed for the trypanosomes in C. dracula in Vietnam and A. yamashinai in Taiwan, respectively. More effort directed toward the morphological and molecular genetic characterization of the trypanosomes of rodents and soricids is required to fully understand the real biodiversity of their hemoflagellates.

Leishmania major and Trypanosoma lewisi infection in invasive and native rodents in Senegal

Bioinvasion is a major public health issue because it can lead to the introduction of pathogens in new areas and favours the emergence of zoonotic diseases. Rodents are prominent invasive species, and act as reservoirs in many zoonotic infectious diseases. The aim of this study was to determine the link between the distribution and spread of two parasite taxa (Leishmania spp. and Trypanosoma lewisi) and the progressive invasion of Senegal by two commensal rodent species (the house mouse Mus musculus domesticus and the black rat Rattus rattus). M. m. domesticus and R. rattus have invaded the northern part and the central/southern part of the country, respectively. Native and invasive rodents were caught in villages and cities along the invasion gradients of both invaders, from coastal localities towards the interior of the land. Molecular diagnosis of the two trypanosomatid infections was performed using spleen specimens. In the north, neither M. m. domesticus nor the native species were carriers of these parasites. Conversely, in the south, 17.5% of R. rattus were infected by L. major and 27.8% by T. lewisi, while very few commensal native rodents were carriers. Prevalence pattern along invasion gradients, together with the knowledge on the geographical distribution of the parasites, suggested that the presence of the two parasites in R. rattus in Senegal is of different origins. Indeed, the invader R. rattus could have been locally infected by the native parasite L. major. Conversely, it could have introduced the exotic parasite T. lewisi in Senegal, the latter appearing to be poorly transmitted to native rodents. Altogether, these data show that R. rattus is a carrier of both parasites and could be responsible for the emergence of new foci of cutaneous leishmaniasis, or for the transmission of atypical human trypanosomiasis in Senegal.

Molecular screening of tsetse flies and cattle reveal different Trypanosoma species including T. grayi and T. theileri in northern Cameroon

BACKGROUND

African trypanosomes are mainly transmitted through the bite of tsetse flies (Glossina spp.). The present study investigated the occurrence of pathogenic trypanosomes in tsetse flies and cattle in tsetse fly-infested areas of Northern Cameroon.

RESULTS

Trypanosomes were identified using nested polymerase chain reaction (PCR) analysis of internal transcribed spacer 1 (ITS1) region, both by size estimation and sequencing of PCR products. Apparent density indices recorded in Gamba and Dodeo were 3.1 and 3.6 tsetse flies per trap and day, respectively. Trypanosoma prevalence infection rate for the tsetse fly gut (40%) and proboscis (19%) were recorded. Among the flies where trypanosomes were detected in the gut, 41.7% were positive for T. congolense and 14.6% for T. brucei ssp., whereas in the proboscis 36% harboured T. congolense and 62% contained T. vivax. T. grayi was highly prevalent in tsetse fly gut (58%). The most common mixed infections were the combination of T. congolense and T. grayi. Trypanosome prevalence rate in cattle blood was 6%. Among these, T. vivax represented 26%, T. congolense 35%, T. brucei ssp. 17% and T. theileri 17% of the infections. Surprisingly, in one case T. grayi was found in cattle. The mean packed cell volume (PCV) of cattle positive for trypanosomes was significantly lower (24.1 ± 5.6%; P < 0.05) than that of cattle in which trypanosomes were not detected (27.1 ± 4.9%). Interestingly, the occurrence of T. theileri or T. grayi DNA in cattle also correlated with low PCV at pathological levels.

CONCLUSION

This molecular epidemiological study of Trypanosoma species in Northern Cameroon revealed active foci of trypanosomes in Dodeo and Gamba. These findings are relevant in assessing the status of trypanosomosis in these regions and will serve as a guide for setting the priorities of the government in the control of the disease.

High Trypanosoma spp. diversity is maintained by bats and triatomines in Espírito Santo state, Brazil

The aim of this study was to reevaluate the ecology of an area in the Atlantic Forest, southeast Brazil, where Chagas disease (CD) has been found to occur. In a previous study, immediately after the occurrence of a CD case, we did not observe any sylvatic small mammals or dogs with Trypanosoma cruzi cruzi infections, but Triatoma vitticeps presented high T. c. cruzi infection rates. In this study, we investigated bats together with non-volant mammals, dogs, and triatomines to explore other possible T. c. cruzi reservoirs/hosts in the area. Seventy-three non-volant mammals and 186 bats were captured at three sites within the Guarapari municipality, Espírito Santo state. Rio da Prata and Amarelos sites exhibited greater richness in terms of non-volant mammals and bats species, respectively. The marsupial Metachirus nudicaudatus, the rodent Trinomys paratus, and the bats Artibeus lituratus and Carollia perspicillata were the most frequently captured species. As determined by positive hemocultures, only two non-volant mammals were found to be infected by Trypanosoma species: Monodelphis americana, which was infected by T. cascavelli, T. dionisii and Trypanosoma sp., and Callithrix geoffroyi, which was infected by T. minasense. Bats presented T. c. cruzi TcI and TcIII/V, T. c. marinkellei, T. dionisii, T. rangeli B and D, and Trypanosoma sp. infections. Seven dogs were infected with T. cruzi based only on serological exams. The triatomines T. vitticeps and Panstrongylus geniculatus were found to be infected by trypanosomes via microscopy. According to molecular characterization, T. vitticeps specimens were infected with T. c. cruzi TcI, TcII, TcIII/V, and TcIV, T. c. marinkellei and T. dionisii. We observed high trypanosome diversity in a small and fragmented region of the Atlantic Forest. This diversity was primarily maintained by bats and T. vitticeps. Our findings show that the host specificity of the Trypanosoma genus should be thoroughly reviewed. In addition, our data show that CD cases can occur without an enzootic cycle near residential areas.

Increased genetic diversity and prevalence of co-infection with Trypanosoma spp. in koalas (Phascolarctos cinereus) and their ticks identified using next-generation sequencing (NGS)

Infections with Trypanosoma spp. have been associated with poor health and decreased survival of koalas (Phascolarctos cinereus), particularly in the presence of concurrent pathogens such as Chlamydia and koala retrovirus. The present study describes the application of a next-generation sequencing (NGS)-based assay to characterise the prevalence and genetic diversity of trypanosome communities in koalas and two native species of ticks (Ixodes holocyclus and I. tasmani) removed from koala hosts. Among 168 koalas tested, 32.2% (95% CI: 25.2–39.8%) were positive for at least one Trypanosoma sp. Previously described Trypanosoma spp. from koalas were identified, including T. irwini (32.1%, 95% CI: 25.2–39.8%), T. gilletti (25%, 95% CI: 18.7–32.3%), T. copemani (27.4%, 95% CI: 20.8–34.8%) and T. vegrandis (10.1%, 95% CI: 6.0–15.7%). Trypanosoma noyesi was detected for the first time in koalas, although at a low prevalence (0.6% 95% CI: 0–3.3%), and a novel species (Trypanosoma sp. AB-2017) was identified at a prevalence of 4.8% (95% CI: 2.1–9.2%). Mixed infections with up to five species were present in 27.4% (95% CI: 21–35%) of the koalas, which was significantly higher than the prevalence of single infections 4.8% (95% CI: 2–9%). Overall, a considerably higher proportion (79.7%) of the Trypanosoma sequences isolated from koala blood samples were identified as T. irwini, suggesting this is the dominant species. Co-infections involving T. gilletti, T. irwini, T. copemani, T. vegrandis and Trypanosoma sp. AB-2017 were also detected in ticks, with T. gilletti and T. copemani being the dominant species within the invertebrate hosts. Direct Sanger sequencing of Trypanosoma 18S rRNA gene amplicons was also performed and results revealed that this method was only able to identify the genotypes with greater amount of reads (according to NGS) within koala samples, which highlights the advantages of NGS in detecting mixed infections. The present study provides new insights on the natural genetic diversity of Trypanosoma communities infecting koalas and constitutes a benchmark for future clinical and epidemiological studies required to quantify the contribution of trypanosome infections on koala survival rates.

Impact estimation of animal trypanosomosis (surra) on livestock productivity in India using simulation model: Current and future perspective

Animal trypanosomosis (surra), caused by Trypanosoma evansi, is one of the most important diseases in livestock and wild animals in India. The disease is prevalent across all agro-climatic regions of India, and has a considerable impact on the country's livestock economy through direct and indirect impact on livestock productivity. In the present study, the economic losses on livestock productivity were assessed resulting from surra in India, considering all possible direct and indirect losses in major six livestock species viz., cattle, buffalo, goat, equine, camel and pig. The contemplative risk and retrospective analyses were performed using various official records and scientific literature complemented with expert data for evaluation of impact of surra on livestock productivity in India. Most of the information were derived using the secondary data published in scientific journals, and the official data reported by Basic Animal Husbandry and Fisheries Statistics (BAHS, 2014), the Government of India and other scientific reports. To address the variability and uncertainty, probability distributions for many input values were used in the present study and sensitivity statistical analyses were conducted using a simulation model. In the current analysis, all prices were assumed as deterministic. Based on present study, a total annual loss (direct and indirect) caused by surra was estimated to US $ 671.1 million or Indian Rupee (INR) 44,740 million (US $ 344-US $ 1209 million or INR 22951.88-80,752.35 million at 95% confidence interval), at present valuation. The mortality losses were estimated to 15.67% of the total loss. Among morbidity losses, the reduction in milk yield and reproductive losses components were 36.46% and 25.72% of total loss, respectively. Other parameters like reduction in growth (9.83%), reduction in draught power (7.95%) and additional opportunity cost (2.93%) also yielded considerable loss. The results highlighted the urgent need for early diagnosis and control strategies for surra in livestock species to reduce the productivity losses in the country's livestock sector.

A comparative molecular and 3-dimensional structural investigation into cross-continental and novel avian Trypanosoma spp. in Australia

BACKGROUND

Molecular and structural information on avian Trypanosoma spp. throughout Australia is limited despite their intrinsic value in understanding trypanosomatid evolution, diversity, and structural biology. In Western Australia tissue samples (n = 429) extracted from 93 birds in 25 bird species were screened using generic PCR primers to investigate the diversity of Trypanosoma spp. To investigate avian trypanosome structural biology the first 3-dimensional ultrastructural models of a Trypanosoma spp. (Trypanosoma sp. AAT) isolated from a bird (currawong, Strepera spp.) were generated using focussed ion beam milling combined with scanning electron microscopy (FIB-SEM).

RESULTS

Here, we confirm four intercontinental species of avian trypanosomes in native Australian birds, and identify a new avian Trypanosoma. Trypanosome infection was identified in 18 birds from 13 different bird species (19%). A single new genotype was isolated and found to be closely related to T. culicavium (Trypanosoma sp. CC2016 B002). Other Trypanosoma spp. identified include T. avium, T. culicavium, T. thomasbancrofti, Trypanosoma sp. TL.AQ.22, Trypanosoma sp. AAT, and an uncharacterised Trypanosoma sp. (group C-III sensu Zidková et al. (Infect Genet Evol 12:102-112, 2012)), all previously identified in Australia or other continents. Serially-sectioning Trypanosoma sp. AAT epimastigotes using FIB-SEM revealed the disc-shaped kinetoplast pocket attached perpendicular to the branching mitochondrion. Additionally, the universal minicircle sequence within the kinetoplast DNA and the associated binding protein were determined in Trypanosoma sp. AAT.

CONCLUSIONS

These results indicate that bird trypanosomes are relatively conserved across continents, while being locally diverse, which supports the hypothesis that bird trypanosomes exist as fewer species than described in the literature. Evidence exists that avian Trypanosoma spp. are infecting mammals and could be transmitted by haemadipsid leeches. Trypanosoma sp. AAT is most likely a separate species currently found only in Australia and the first 3-dimentional ultrastructural analysis of an avian trypanosome provides interesting information on their morphology and organelle arrangement.

Epidemiological study of common diseases and their risk factors in camels in South Punjab, Pakistan

Bacteriological study of mastitis along with common blood protozoan diseases were studied in dromedary camels in Cholistan, Dera Ismail Khan and Rahim Yar Khan districts in South Punjab, Pakistan. For this purpose 300 camels were sampled randomly at different common grazing and watering point. For study of blood parasites clinically suspected and apparently healthy camels, 150 each, were sampled. An overall prevalence of 15%and 5% was recorded for trypanosomiasis and Anaplasmosis respectively. Trypanosoma evansi was identified with 280 bp product on polymerase chain reaction test. There was significant (P < 0.05) decline in the values of total erythrocyte counts, hemoglobin concentration, packed cell volume, serum total proteins and albumin while erythrocyte sedimentation rate was increased in infected camels as compared to healthy ones. Aspartate aminotransferase, alanine aminotransferase, gamma glutamyltransferase and alkaline phosphatase were also significantly increased in blood protozoan the infected animals. Milk samples for bacteriology were collected from healthy lactating camels (n = 100). Information about different risk factors were gathered on designed performa. Subclinical mastitis on surf field test was recorded in 42% camels while 2% cases of clinical mastitis were recorded. Staphylococcus aureus, Streptococcus agalactiae, Streptococcus dysgalactiae, Bacillus cereus and. Corynebacterium kutscheri were isolated with characteristic beta and alpha hemolysis patterns. Chi-square analysis showed significant difference as p < 0.05 among various species of bacteria (χ2 = 21.649, P-Value = 0.0001, df = 3). Antibiogram showed Gentamicin, Norfloxacin, Oxytetracycline as most effective therapy for mastitis in camel.

Intra and inter species genetic variability of transferrin receptor gene regions in Trypanosoma evansi isolates of different livestock and geographical regions of India

Trypanosoma evansi, the aetiological agent of Surra affects a wide range of livestock and wild animals in India. In the present study, we studied intra- and inter species genetic variability in the transferrin receptor encoding gene regions (ESAG6/7 gene region) of T. evansi isolates by cloning, sequencing and phylogenetic study collected from camel, cattle, donkeys and ponies from North-Western and Central India. The nucleotide sequence variation of ESAG6/7 gene region between Indian T. evansi isolates was up to 17.7% and amino acid sequence variation was up to 31%. Twenty nine clones from six T. evansi isolates from geographical regions of India were included into Clade 1, 5, 6, 7 and 9 consisting of ESAG6 variants reported among T. evansi isolates from South-east Asia and South America. The cladogram indicated a relation between the host species and the genetic variability in the hyper-variable region of ESAG6 gene. Analysis of the Indian ESAG6 variants and their respective Clade positions presented a host specific distribution indicating homogenous parasite population in their respective animal hosts.

A Multi-Host Agent-Based Model for a Zoonotic, Vector-Borne Disease. A Case Study on Trypanosomiasis in Eastern Province, Zambia

BACKGROUND

This paper presents a new agent-based model (ABM) for investigating T. b. rhodesiense human African trypanosomiasis (rHAT) disease dynamics, produced to aid a greater understanding of disease transmission, and essential for development of appropriate mitigation strategies.

METHODS

The ABM was developed to model rHAT incidence at a fine spatial scale along a 75 km transect in the Luangwa Valley, Zambia. The method offers a complementary approach to traditional compartmentalised modelling techniques, permitting incorporation of fine scale demographic data such as ethnicity, age and gender into the simulation.

RESULTS

Through identification of possible spatial, demographic and behavioural characteristics which may have differing implications for rHAT risk in the region, the ABM produced output that could not be readily generated by other techniques. On average there were 1.99 (S.E. 0.245) human infections and 1.83 (S.E. 0.183) cattle infections per 6 month period. The model output identified that the approximate incidence rate (per 1000 person-years) was lower amongst cattle owning households (0.079, S.E. 0.017), than those without cattle (0.134, S.E. 0.017). Immigrant tribes (e.g. Bemba I.R. = 0.353, S.E.0.155) and school-age children (e.g. 5-10 year old I.R. = 0.239, S.E. 0.041) were the most at-risk for acquiring infection. These findings have the potential to aid the targeting of future mitigation strategies.

CONCLUSION

ABMs provide an alternative way of thinking about HAT and NTDs more generally, offering a solution to the investigation of local-scale questions, and which generate results that can be easily disseminated to those affected. The ABM can be used as a tool for scenario testing at an appropriate spatial scale to allow the design of logistically feasible mitigation strategies suggested by model output. This is of particular importance where resources are limited and management strategies are often pushed to the local scale.

Health and epidemiological approaches of Trypanosoma evansi and equine infectious anemia virus in naturally infected horses at southern Pantanal

Equine infectious anemia virus (EIAV) and Trypanossoma evansi are endemic in Brazilian Pantanal Biome, an important area for livestock production. In this sense, we evaluated the epidemiological single and co-infection effects of T. evansi and EIAV in naturally infected horses in the southern Pantanal wetland by serological tests and hematological assays. Both higher seroprevalence and heath poor condition of the sampled animals were associated with differences in horse management between farms. We found that the negative animals for both infectious agents (NN) represented the major group in F1 (37%), and the smallest group in F2 (19%). Furthermore, we recorded higher EIAV seroprevalence (56%) in F2, compared to F1 (38%). We observed that T. evansi infection was mostly related to young horses, as seen by their higher seroprevalence, ranging from 70.7% in the beginning of the rainy season to 81% in the end of flood period, in comparison with the values of 42% and 68%, respectively, in working animals. on the other hand, working animals showed a higher seroprevalence for EIAV (48%) in both seasons than young horses. We observed that the management of working horses could be a risk factor of EIAV infection. On the other hand, as T. evansi is maintained in the study region by many species of wild mammals, the mechanical transmission through blood-sucking vectors ensures the infection to horses since early. Our results showed that single or co-infection by EIAV and T. evansi caused different degree of anemia in the infected animals. Moreover, the health of horses in Brazilian Pantanal is also influenced by differences in horse management and environmental circumstances.

Stakeholder Narratives on Trypanosomiasis, Their Effect on Policy and the Scope for One Health

Background

This paper explores the framings of trypanosomiasis, a widespread and potentially fatal zoonotic disease transmitted by tsetse flies (Glossina species) affecting both humans and livestock. This is a country case study focusing on the political economy of knowledge in Zambia. It is a pertinent time to examine this issue as human population growth and other factors have led to migration into tsetse-inhabited areas with little historical influence from livestock. Disease transmission in new human-wildlife interfaces such as these is a greater risk, and opinions on the best way to manage this are deeply divided.

Methods

A qualitative case study method was used to examine the narratives on trypanosomiasis in the Zambian policy context through a series of key informant interviews. Interviewees included key actors from international organisations, research organisations and local activists from a variety of perspectives acknowledging the need to explore the relationships between the human, animal and environmental sectors.

Principal Findings

Diverse framings are held by key actors looking from, variously, the perspectives of wildlife and environmental protection, agricultural development, poverty alleviation, and veterinary and public health. From these viewpoints, four narratives about trypanosomiasis policy were identified, focused around four different beliefs: that trypanosomiasis is protecting the environment, is causing poverty, is not a major problem, and finally, that it is a Zambian rather than international issue to contend with. Within these narratives there are also conflicting views on the best control methods to use and different reasoning behind the pathways of response. These are based on apparently incompatible priorities of people, land, animals, the economy and the environment. The extent to which a One Health approach has been embraced and the potential usefulness of this as a way of reconciling the aims of these framings and narratives is considered throughout the paper.

Conclusions/Significance

While there has historically been a lack of One Health working in this context, the complex, interacting factors that impact the disease show the need for cross-sector, interdisciplinary decision making to stop rival narratives leading to competing actions. Additional recommendations include implementing: surveillance to assess under-reporting of disease and consequential under-estimation of disease risk; evidence-based decision making; increased and structurally managed funding across countries; and focus on interactions between disease drivers, disease incidence at the community level, and poverty and equity impacts.

This paper explores the differing opinions of various stakeholders in relation to trypanosomiasis, a widespread and potentially fatal disease spread by tsetse flies which affects both humans and animals. It is an important time to examine this issue as human population growth and other factors have led to migration into new areas which are populated by tsetse flies, and this may affect disease levels. This means that there is a greater risk to people and their livestock, and opinions on the best way to manage the disease are deeply divided. Cross sector working hasn’t been used historically, but breaking down the barriers between social scientists, natural scientists and the expertise of the community could lead to better disease management.

Blood parasites in northern goshawk (Accipiter gentilis) with an emphasis to Leucocytozoon toddi

Haemosporidians and trypanosomes of the northern goshawk (Accipiter gentilis) population in the Czech Republic were studied by morphological and molecular methods. Despite the wide distribution of these medium-large birds of prey, virtually nothing is known about their blood parasites. During a 5-year period, altogether 88 nestlings and 15 adults were screened for haemosporidians and trypanosomes by microscopic examination of blood smears and by nested PCR. Both methods revealed consistently higher prevalence of blood protists in adults, Leucocytozoon (80.0 % in adults vs. 13.6 % in nestlings), Haemoproteus (60.0 vs. 2.3 %), Plasmodium (6.7 vs. 0 %), and Trypanosoma (60.0 vs. 2.3 %). Altogether, five haemosporidian lineages were detected by cytochrome b sequencing. Two broadly distributed and host nonspecific lineages, Plasmodium (TURDUS1) and Leucocytozoon (BT2), were detected only sporadically, while three newly described northern goshawk host-specific Leucocytozoon lineages (ACGE01-03) represent the absolute majority of the haemosporidians identified by molecular methods. Our findings support evidences that in falconiform birds the Leucocytozoon toddi group is formed by several host-specific clusters, with Leucocytozoon buteonis in buzzards and Leucocytozoon mathisi in hawks. Between-year comparisons revealed that the infection status of adults remained predominantly unchanged and individuals stayed uninfected or possessed the same parasite lineages; however, two gains and one loss of blood parasite taxa were also recorded.

Sero-diagnosis of surra exploiting recombinant VSG antigen based ELISA for surveillance

Trypanosoma evansi, a haemoflagellate, causes "surra" an important chronic wasting disease of a wide range of wild and domestic herbivorous and carnivorous animals including cattle, buffaloes, camels, horses, etc. The untreated recovered animal can act as a carrier without exhibiting the disease symptoms and can be a source of infection to healthy animals. The diagnosis and subsequent treatment of the carrier animals is helpful to curb the disease. As the parasitaemia in carrier animals is very scanty, the conventional blood smear examination, which is widely practiced in the field, cannot detect such condition. For this purpose improved diagnostics are very much useful for mass sero-screening test such as ELISA. In the present study, the VSG of T. evansi was expressed in prokaryotic system (E. coli) and thereafter its immunoreactivity has been evaluated in immuno blot and enzyme immuno assay. The expressed protein showed 95.6% sensitivity, 98.0% specificity and 0.93 Cohen's kappa value, when compared with standard antigens. The developed antigen has also been validated with field serum samples from bovine, camel and horse collected from different states of India. The data showed that the developed recombinant antigen can be a diagnostic tool to detect carrier animals as well as control of the disease.

Quantifying the association between bovine and human trypanosomiasis in newly affected sleeping sickness areas of Uganda

BACKGROUND

Uganda has active foci of both chronic and acute HAT with the acute zoonotic form of disease classically considered to be restricted to southeast Uganda, while the focus of the chronic form of HAT was confined to the northwest of the country. Acute HAT has however been migrating from its traditional disease focus, spreading rapidly to new districts, a spread linked to movement of infected cattle following restocking. Cattle act as long-term reservoirs of human infective T. b. rhodesiense showing few signs of morbidity, yet posing a significant risk to human health. It is important to understand the relationship between infected cattle and infected individuals so that an appropriate response can be made to the risk posed to the community from animals infected with human pathogens in a village setting.

METHODOLOGY/PRINCIPAL FINDINGS

This paper examines the relationship between human T. b. rhodesiense infection and human infective and non-human T. brucei s.l. circulating in cattle at village level in Kaberamaido and Dokolo Districts, Uganda. The study was undertaken in villages that had reported a case of sleeping sickness in the six months prior to sample collection and those villages that had never reported a case of sleeping sickness.

CONCLUSIONS AND SIGNIFICANCE

The sleeping sickness status of the villages had a significant effect with higher odds of infection in cattle from case than from non-case villages for T. brucei s.l. (OR: 2.94, 95%CI: 1.38-6.24). Cattle age had a significant effect (p<0.001) on the likelihood of T. brucei s.l. infection within cattle: cattle between 18-36 months (OR: 3.51, 95%CI: 1.63-7.51) and cattle over 36 months (OR: 4.20, 95%CI: 2.08-8.67) had significantly higher odds of T. brucei s. l. infection than cattle under 18 months of age. Furthermore, village human sleeping sickness status had a significant effect (p<0.05) on the detection of T. b. rhodesiense in the village cattle herd, with significantly higher likelihood of T. b. rhodesiense in the village cattle of case villages (OR: 25, 95%CI: 1.2-520.71). Overall a higher than average T. brucei s.l. prevalence (>16.3%) in a village herd over was associated with significantly higher likelihood of T. b. rhodesiense being detected in a herd (OR: 25, 95%CI: 1.2-520.71).

Control and eventual eradication of Trypanosoma evansi infection in dromedary camels after an episodic outbreak in mainland Spain: an example in a non-endemic area

In 2008, Trypanosoma evansi was detected on a camel farm in mainland Spain. The animals were isolated, confined in a closed stable, and treated twice with melarsamine (Cymelarsan(®), Merial, Lyon, France) with an interval of 1 month. Clinical and laboratory examinations by means of parasitological, serological, and molecular procedures (polymerase chain reaction (PCR)) were carried out regularly for 6 years. After the treatment, all parasitemic camels were cleared of parasites, and in the seropositive camels a progressive decrease in antibody levels was observed, with complete disappearance of antibodies between 15 and 21 months, except in one animal which showed doubtful Ag-Ab reaction at 21 months post treatment. In the next assessment, 6 months later, the diagnostic tests conducted on all animals had a negative result. The diagnostic and therapeutic tools recently developed against T. evansi will evidence new and alternative approaches after the parasite is detected, particularly if outbreak occurs in geographically localized areas in territories free of the disease.

Survey of Trypanosoma and Leishmania in wild and domestic animals in an Atlantic rainforest fragment and surroundings in the state of Espírito Santo, Brazil

Trypanosoma and Leishmania infections affect wild and domestic animals and human populations. The growing process of deforestation and urbanization of Atlantic Rainforest areas has given rise to introduction of humans and domestic animals to the sylvatic cycles of Trypanosoma and Leishmania species. Serological, parasitological, and molecular surveys among wild and domestic animals in the Corrego do Veado Biological Reserve, which is an Atlantic Rainforest fragment in the state of Espírito Santo, southeastern Brazil, were evaluated. In total, 154 wild animals of 25 species and 67 domestic animals (47 dogs and 20 horses) were sampled. All the domestic animals were serologically negative for anti-Leishmania infantum chagasi antibodies and negative in parasitological approaches. Only the Order Chiroptera presented positive blood cultures and cryopreserved isolates. The phylogenetic trees based on SSU rDNA and gGAPDH genes confirmed the occurrence of Trypanosoma dionisii and provided the first record of Trypanosoma cruzi marinkellei in southeastern Brazil. The studies conducted in Atlantic Rainforest remaining trees provide the knowledge of parasite diversity or detect parasites that can accelerate the loss of hosts diversity.

Selected haematological changes in Clarias gariepinus (Burchell, 1822) infected with a Trypansosoma sp. from the Vaal Dam, South Africa

The use of haematological techniques to assess fish health is generally accepted. The aim of the current study was to determine selected haematological changes that occur in Clarias gariepinus (Burchell, 1822). infected with trypanosomes. Blood films were prepared according to standard techniques to confirm trypanosome infections and whole blood was collected, the serum and plasma separated, and prepared for albumin and total protein concentration analysis. Plasma albumin levels were significantly higher in infected wild caught fish than in uninfected wild caught fish and uninfected breeding stock. Serum albumin levels were significantly lower in infected wild caught fish when compared to uninfected breeding stock. The total plasma and serum protein levels were within the normal range for C. gariepinus, that is, 3 g-6 g/100 mL. The total plasma protein levels varied significantly between the three groups. However, the total serum protein levels were only significantly different between uninfected breeding stock and uninfected wild caught fish, as well as uninfected breeding stock and infected wild caught fish. The total protein levels were significantly higher in infected wild caught fish than in the other groups, a possible indication of an infection or inflammatory host response.