ABSTRAK Pendahuluan :Trypanosoma evansi adalah protozoa berflagella yang bersirkulasidi dalam darah secara ekstraseluler sebagai agen penyakit Surra serta menyerangseluruh hewan vertebrata, serta berpotensi sebagai zoonosis. Informasi virulensiisolat T. evansi sangat dibutuhkan untuk penentuan strategi pengobatan Surra didaerah wabah dan endemis. Penelitian ini bertujuan untuk mengetahui variasivirulensi isolat T. evansi yang dikoleksi dari berbagai wilayah di Indonesiatermasuk memperoleh marka genetik serta mengetahui profil sitokin pada mencit.Disamping itu, dilakukan juga uji serologis pada peternak di daerah wabah SurraMetode : Sebanyak 32 isolat lokal T. evansi dikonfimasi dengan PCR multiplex(ITS-1; Te Ro Tat 1,2 VSG dan ESAG6/7), selanjutnya diuji virulensinya denganmenginfeksikan104 parasit pada mencit galur DDY. Studi genotyping populasiT. evansi dievaluasi dengan 8 marka mikrosatelit Tbb-1, Tbb-5, Tbb-9, Tbb-10,MORF2-CA, M6C8-CA, MEST-19AT, MT3033-AT. Dua isolat yang berbedavirulensi (tinggi-Bang87 dan rendah-Pml 287) dipilih untuk uji imunopatogenitassedangkan serum peternak diuji dengan metode FELISA dan CATT T. evansi.Hasil : Dari 32 isolat tersebut terbagi menjadi 17 isolat bervirulensi tinggi, 11isolat bervirulensi moderat dan 4 isolat bervirulensi rendah dengan 8 pola tingkatparasitemia. Analisis Neigbour Joining (NJ) terhadap 8 lokus berdasarkan MultiLokus Genotipe (MLG) mikrosatelit terbagi menjadi 4 populasi, yaitu MLG A,MLG B, MLG C dan MLG D. Analisis terhadap struktur populasi jugamemberikan hasil yang sama dengan terbentuknya 4 klaster. Hasil ini jugamembuktikan bahwa marka yang digunakan bersifat spesifik lokasi. Sebanyaktiga marka mengindikasikan adanya asosiasi antara virulensi dan MLG (Tbb-1,M6C8-CA dan MEST-19). Kadar IFN-γ meningkat secara tajam pada mencityang diinfeksi isolat Bang 87 pada 4hpi berkorelasi negatif yang signifikan(p<0,05) dengan kadar IL-10, sedangkan pada mencit yang diinfeksi isolat Pml287, peningkatan kadar IFNγ berkorelasi positif dengan kadar IL-10. Kematiandini pada mencit yang diinfeksi isolat Bang 87 disebabkan oleh sindrom responinflamasi sitemik. Hasil uji serologis menunjukkan bahwa 4 dari 24 serumpeternak (16,67%) didaerah wabah positif dan seluruh serum negatif untukdaerah non wabah.Kesimpulan : Variasi virulensi T. evansi isolat Indonesia memiliki karaktermolekular yang berbeda serta menginduksi pola mediator sitokin pro danantiinflamasi yang berhubungan dengan pola manifestasi patologi yang berbeda.Marka mikrosatelit pada studi ini mampu mengidentifikasi asal usul sumberinfeksi, dan tingkat virulensi isolat yang sedang bersirkulasi. Surra berpotensisebagai emerging zoonosis, terutama bagi peternak didaerah wabah dan endemis. ABSTRACT Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas;Introduction: Trypanosoma evansi is an extracellular homoflagellate ofprotozoan blood causing Surra. The disease attacks all vertebrates and potentiallyas zoonosis. Virulence analysis of T. evansi is a fundamental knowledge todetermine treatment strategies of Surra in both outbreak and endemic areas. Theaims of this study was to determine virulence variation of T. evansi isolatescollected from various regions in Indonesia and to obtained genetic markers aswell as cytokine profile in mice. In addition, serological test was also carried outto farmers living in a Surra outbreak areaMethods: Total of 32 isolates of T. evansi corfirmed with multiplex PCR (ITS-1;Te Ro Tat 1.2 VSG and ESAG6 / 7), were further tested with inoculation 104parasite in DDY mice strain. The population genotype study of T. evansi wasevaluated with 8 microsatellite markers (Tbb-1, Tbb-5, Tbb-9, Tbb-10-CAMORF2, M6C8-CA, MEST-19AT, MT3033-AT). Two different virulenceisolates, high-Bang87 and low-PML287 was selected to cytokine profile analysisusing ELISA, while farmers sera were tested using CATT and FELISA kitsResults: A total of 32 local isolates of T. evansi tested were divided into threedifferent virulences, i.e. 17 high virulence isolates, 11 moderate virulence and 4low virulence isolates forming 8 pattern parasitemia levels. Based on NeigbourJoining (NJ) on 8 Microsatellite Multilocus Genotype (MLGs) was grouped into4 populations (MLG A, MLG B, MLG C and MLG D). Stucture populationanalysis also provided the similar result generating 4 clusters. These resultsindicated that the markers used in this study had a specific location property.Three markers (TBB-1, and MEST M6C8-CA-19) showed an associationbetween virulence and MLG. IFN-γ levels increased significantly in miceinfected with Bang 87 isolate on 4th day post infection (dpi) having a significantnegative correlation (p <0.05) with increased IL-10 levels, whereas in miceinfected by PML 287 isolate, IFN-γ levels were positively correlated with IL- 10levels. Early death in mice infected with Bang87 isolates was caused by systemicinflammatory response syndrome (SIRS). Result of serological test showed that 4 outof 24 farmers sera (16.67%) from outbreak areas are positive and all sample fromfree area are negative.Conclusion: Virulence variation of T. evansi isolates from Indonesia hasdifferent molecular character and induces cytokine pattern of pro and antiinflammatorymediators associated with distinct patterns of pathologicalmanifestations. The microsatellite markers found in this study are able to identifyorigin of infection sources dan determine virulence of isolates that circulate on theoutbreak area. Surra is potential new emerging disease, particularly for farmers orimmunosurpressed individuals who living in both endemic and outbreak areas |