Serological evidence of arboviruses and coccidia infecting horses in the Amazonian region of Brazil

Autoři: Fábio Alves Gomes aff001;  Ana Maria Jansen aff001;  Rosângela Zacarias Machado aff003;  Hilda Fátima Jesus Pena aff004;  Marcílio Jorge Fumagalli aff005;  Angélica Silva aff005;  Bruna Farias Alves aff004;  André Luiz Rodrigues Roque aff001;  Luiz Tadeu Moraes Figueiredo aff005
Působiště autorů: Laboratory of Trypanosomatid Biology, Oswaldo Cruz Institute, FIOCRUZ, Rio de Janeiro, Rio de Janeiro, Brazil aff001;  Federal Institute of Education Science and Technology of Roraima, Caracaraí, Roraima, Brazil aff002;  School of Agricultural and Veterinary Studies of Jaboticabal, São Paulo State University, Jaboticabal, Brazil aff003;  School of Veterinary and Animal Science, Department of Preventive Veterinary and Animal Health, University of São Paulo, São Paulo, Brazil aff004;  Virology Research Center, Ribeirão Preto Medical School, University of São Paulo, Ribeirão Preto, Brazil aff005
Vyšlo v časopise: PLoS ONE 14(12)
Kategorie: Research Article



Arboviruses and protozoans can cause neurologic disorders in horses. In Brazilian Amazon, several horses presenting signs compatible with disorders caused by these infectious agents have been observed.


To contribute to the knowledge of this epidemiological picture, we sought to construct a serological diagnostic panel for neurotrophic infectious agents in local horses.

Material and methods

A total of 213 blood samples from horses were collected from 29 farms in three municipalities. Samples were evaluated and considered positive when they met the following criteria: titers ≥ 1:80 with the indirect fluorescent antibody test (IFAT) for apicomplexan protozoans; positive recombinant enzyme-linked immunosorbent assay (ELISA) with subsequent titers ≥ 1:10 by the PRNt for viruses; and detection under direct microscopic examination for Trypanosoma evansi.


No horses were found to be infected by T. evansi, and only two were infected Toxoplasma gondii and/or Neospora spp. The highest protozoan infection rate was observed for Sarcocystis neurona (40.3%; n = 86/213). Among the positive ELISA samples tested by the plaque reduction neutralization test (PRNT90), 92% (n = 76/83) were positive for St Louis Encephalitis virus, 43% (n = 6/14) were positive for West Nile virus and 33% (n = 16/48) were positive for Mayaro virus. Eighteen percent (n = 39/213) of horses were co-infected by S. neurona and at least one arbovirus, particularly SLEV and/or MAYV.


Samples positive for SLEV associated with S. neurona, including samples from horses that had recovered from neurological signs were frequent, and must be considered when investigating the possible causes of neurological diseases in South Roraima horses.

Klíčová slova:

Arboviral infections – Brazil – Enzyme-linked immunoassays – Horses – Mayaro virus – Protozoan infections – Trypanosoma – West Nile virus


1. Dubey JP, Mitchell SM, Morrow JK, Rhyan JC, Stewart LM, Granstrom DE, et al. Prevalence of antibodies to Neospora caninum, Sarcocystis neurona, and Toxoplasma gondii in wild horses from central Wyoming. Journal of Parasitology. 2003;89: 716–720. doi: 10.1645/GE-66R 14533680

2. Dubey JP, Howe DK, Furr M, Saville WJ, Marsh AE, Reed SM, et al. An update on Sarcosystis neurona infections in animals and equine protozoal myeloencephalitis (EPM). Veterinary Parasitology. 2015;209: 1–42. doi: 10.1016/j.vetpar.2015.01.026 25737052

3. Fenger CK, Granstrom DE, Gajadhar AA, Williams NM, McCrillis SA, Stamper S, et al. Experimental induction of equine protozoal myeloencephalitis in horses using Sarcocystis sp. sporocysts from the opossum (Didelphis virginiana). Veterinary Parasitology. 1997;68: 199–213. doi: 10.1016/s0304-4017(96)01112-0 9066066

4. Dubey JP, Lindsay DS. Isolation in immunodeficient mice of Sarcosystis neurona from opossum (Didelphis virginiana) faeces, and its differentiation from Sarcocystis falcatula. International Journal for Parasitology. 1998;28: 1823–1828. doi: 10.1016/s0020-7519(98)00166-0 9925260

5. Chapman GE, Baylis M, Archer D, Daly JM. The challenges posed by equine arboviruses. Equine Veterinary Journal. 2018;50: 436–445. doi: 10.1111/evj.12829 29517814

6. Weaver SC, Barrett ADT. Transmission cycles, host range, evolution and emergence of arboviral disease. Nature Reviews Microbiology. 2004;2: 789–801. doi: 10.1038/nrmicro1006 15378043

7. Gould E, Pettersson J, Higgs S, Charrel R, de Lamballerie X. Emerging arboviruses: Why today? One Health. 2017;4: 1–13. doi: 10.1016/j.onehlt.2017.06.001 28785601

8. Figueiredo LTM. Emergent arboviruses in Brazil. Revista da Sociedade Brasileira de Medicina Tropical. 2007;40: 224–229. doi: 10.1590/s0037-86822007000200016 17568894

9. Castillo-Olivares J, Wood J. West Nile virus infection of horses. Veterinary Research. 2004;35: 467–483. doi: 10.1051/vetres:2004022 15236677

10. Auguste AJ, Pybus OG, Carrington CVF. Evolution and dispersal of St. Louis encephalitis virus in the Americas. Infection, Genetics and Evolution. 2009;9: 709–715. doi: 10.1016/j.meegid.2008.07.006 18708161

11. Terzian ACB, Mondini A, de Moraes Bronzoni RV, Drumond BP, Ferro BP, Cabrera EMS, et al. Detection of Saint Louis Encephalitis Virus in Dengue-Suspected Cases During a Dengue 3 Outbreak. Vector-Borne and Zoonotic Diseases. 2011;11: 291–300. doi: 10.1089/vbz.2009.0200 20645866

12. Carrera J-P, Forrester N, Wang E, Vittor AY, Haddow AD, López-Vergès S, et al. Eastern Equine Encephalitis in Latin America. New England Journal of Medicine. 2013;369: 732–744. doi: 10.1056/NEJMoa1212628 23964935

13. Travassos da Rosa J.F.S., Freitas E.M., Travassos da Rosa A.P.A., Pinheiro F.P. Eidemiologia do vírus da encefalite de São Luis na Amazônia, Revista da FSESP. 1980; 25 73–80.

14. Travassos da Rosa J.F.S., Travassos da Rosa A.P.A., Vasconcelos P.F.C., Rodrigues S.G., Travassos da Rosa E.S., Dias L.B., Cruzi A.C.R., Arboviruses isolated in the Evandro Chagas Institute, including some described for the first time in the Brazilian Amazon region, their known hosts, and their pathology for man, in: Travassos da Rosa A.P.A., Vasconcelos P.F.C., Travassos da Rosa J.F.S. (Eds.), An Overview of Arbovirology on Brazil and Neighboring Countries, Instituto Evandro Chagas, Belem. 1998; 19–31

15. Rosa R, Costa EA, Marques RE, Oliveira TS, Furtini R, Bomfim MRQ, et al. Isolation of Saint Louis Encephalitis Virus from a Horse with Neurological Disease in Brazil. Weaver SC, editor. PLoS Neglected Tropical Diseases. 2013;7: e2537. doi: 10.1371/journal.pntd.0002537 24278489

16. Reisen WK, Fang Y, Martinez VM. Avian Host and Mosquito (Diptera: Culicidae) Vector Competence Determine the Efficiency of West Nile and St. Louis Encephalitis Virus Transmission. Journal of medical entomology. 2005;42: 9.

17. Napp S, Petrić D, Busquets N. West Nile virus and other mosquito-borne viruses present in Eastern Europe. Pathogens and Global Health. 2018;112: 233–248. doi: 10.1080/20477724.2018.1483567 29979950

18. Barbosa M das GV, Fé NF, Marcião AHR, Silva APT da, Monteiro WM, Guerra MV de F, et al. Record of epidemiologically important Culicidae in the rural area of Manaus, Amazonas. Revista da Sociedade Brasileira de Medicina Tropical. 2008;41: 658–663. doi: 10.1590/s0037-86822008000600019 19142448

19. Klein TA, Lima JBP, Tang AT, Klein TA, Lima JBP, Tang AT. Seasonal distribution and diel biting patterns of culicine mosquitoes in Costa Marques, Rondônia, Brazil. Memórias do Instituto Oswaldo Cruz. 1992;87: 141–148. doi: 10.1590/s0074-02761992000100021 1364053

20. Korte RL, Fontes G, Camargo J de SAA, Rocha EMM da, Araújo EAC de, Oliveira MZ de, et al. Survey of Bancroftian filariasis infection in humans and Culex mosquitoes in the western Brazilian Amazon region: implications for transmission and control. Revista da Sociedade Brasileira de Medicina Tropical. 2013;46: 214–220. doi: 10.1590/0037-8682-1708-2013 23740057

21. Pinheiro FP, Freitas RB, Travassos da Rosa JF, Gabbay YB, Mello WA, LeDuc JW, Travassos da Rosa A. An outbreak of Mayaro virus disease in Belterra, Brazil. I. Clinical and virological findings. American Journal of Tropical Medicine and Hygiene. 1981;30:674–81 doi: 10.4269/ajtmh.1981.30.674 6266263

22. Lopes OS, de Abreu Sacchetta L, Francy DB, Jakob WL, Calisher CH. Emergence of a new arbovirus disease in Brazil. III. Isolation of Rocio virus from Psorophora Ferox (Humboldt, 1819). American Journal of Epidemiology, 1981; 113:122–125. doi: 10.1093/oxfordjournals.aje.a113075 6110335

23. Hoch AL, Peterson NE, Le Duc JN, Pinheiro FP. An outbreak of Mayaro virus disease in Belterra, Brazil. III. Entomological and ecological studies. American Journal of Tropical Medicine and Hygiene.1981;30:689–98. doi: 10.4269/ajtmh.1981.30.689 6266265

24. Azevedo RSS, Silva EVP, Carvalho VL, Rodrigues SG, Neto JPN, Monteiro HAO, et al. Mayaro Fever Virus, Brazilian Amazon. Emerging Infectious Diseases. 2009;15: 1830–1832. doi: 10.3201/eid1511.090461 19891877

25. de Thoisy B, Gardon J, Salas RA, Morvan J, Kazanji M. Mayaro Virus in Wild Mammals, French Guiana. Emerging Infectious Diseases. 2003;9: 1326–1329. doi: 10.3201/eid0910.030161 14609474

26. Woo PTK. The haematocrit centrifuge for the detection of trypanosomes in blood. Canadian Journal of Zoology. 1969;47: 921–923. doi: 10.1139/z69-150 5343381

27. Camargo M. E. Introdução as técnicas de imunofluorescência. Revista Brasileira Patologia Clínica, 1974; 10: 87–107.

28. Dubey JP; Carpenter JL; Speer CA; Topper MJ; Uggla A. Newly recognized fatal protozoan disease of dogs. Journal American Veterinary Medicine Association, 1988;192, 9: 1269–1285.

29. Duarte PC, Daft BM, Conrad PA, Packham AE, Gardner IA. Comparison of a serum indirect fluorescent antibody test with two western blot tests for the diagnosis of equine protozoal myeloencephalitis. Journal of Veterinary Diagnostic Investigation. 2003;15: 8–13. doi: 10.1177/104063870301500103 12580288

30. Chávez JH, Silva JR, Amarilla AA, Moraes Figueiredo LT. Domain III peptides from Flavivirus envelope protein are useful antigens for serologic diagnosis and targets for immunization. Biologicals. 2010;38: 613–618. doi: 10.1016/j.biologicals.2010.07.004 20817489

31. Fumagalli MJ, de Souza WM, Romeiro MF, de Souza Costa MC, Slhessarenko RD, Figueiredo LTM. Development of an Enzyme-Linked Immunosorbent Assay To Detect Antibodies Targeting Recombinant Envelope Protein 2 of Mayaro Virus. Tang Y-W, editor. J Clin Microbiol. 2019;57. doi: 10.1128/JCM.01892-18 30787146

32. Earley E, Peralta PH, Johnson KM. A Plaque Neutralization Method for Arboviruses. Experimental Biology and Medicine. 1967;125: 741–747. doi: 10.3181/00379727-125-32194 15938255

33. Dubey JP, Barr BC, Barta JR, Bjerkås I, Björkman C, Blagburn BL, et al. Redescription of Neospora caninum and its differentiation from related coccidia. International Journal for Parasitology. 2002;32: 929–946. doi: 10.1016/s0020-7519(02)00094-2 12076623

34. Silva RAMS, Arosemena NAE, Herrera HM, Sahib CA, Ferreira MSJ. Outbreak of trypanosomosis due to Trypanosoma evansi in horses of Pantanal Mato-grossense, Brazil. Veterinary Parasitology. 1995;60: 167–171. doi: 10.1016/0304-4017(94)00757-4 8644453

35. Basso W, Venturini L, Venturini MC, Moore P, Rambeau M, Unzaga JM, et al. Prevalence of Neospora caninum Infection in Dogs From Beef-Cattle Farms, Dairy Farms, and From Urban Areas of Argentina. Journal of Parasitology, 2001; 87(4):906–907. doi: 10.1645/0022-3395(2001)087[0906:PONCII]2.0.CO;2 11534656

36. Paré J, Fecteau G, Fortin M, Marsolais G. Seroepidemiologic study of Neospora caninum in dairy herds. Journal of the American Veterinary Medical Association. 1998;213: 1595–1598. 9838960

37. Dubey JP, Mitchell SM, Morrow JK, Rhyan JC, Stewart LM, Granstrom DE, et al. Prevalence of antibodies to Neospora caninum, Sarcocystis neurona, and Toxoplasma gondii in wild horses from central wyoming. Journal of Parasitology. 2003;89: 716–720. doi: 10.1645/GE-66R 14533680

38. Ribeiro MJM, Rosa MHF, Bruhn FRP, Garcia A de M, Rocha CMBM da, Guimarães AM. Seroepidemiology of Sarcosystis neurona, Toxoplasma gondii and Neospora spp. among horses in the south of the state of Minas Gerais, Brazil. Revista Brasileira de Parasitologia Veterinária. 2016;25: 142–150. doi: 10.1590/S1984-29612016029 27334814

39. Hoane JS, Gennari SM, Dubey JP, Ribeiro MG, Borges AS, Yai LEO, et al. Prevalence of Sarcosystis neurona and Neospora spp. infection in horses from Brazil based on presence of serum antibodies to parasite surface antigen. Veterinary Parasitology. 2006;136: 155–159. doi: 10.1016/j.vetpar.2005.10.023 16310955

40. Calisher CH, Karabatsos N, Dalrymple JM, Shope RE, Porterfield JS, Westaway EG, et al. Antigenic Relationships between Flaviviruses as Determined by Cross-neutralization Tests with Polyclonal Antisera. Journal of General Virology. 1989;70: 37–43. doi: 10.1099/0022-1317-70-1-37 2543738

41. Kuno G. Serodiagnosis of Flaviviral Infections and Vaccinations in Humans. Advances in Virus Research. Elsevier. 2003; 3–65. doi: 10.1016/s0065-3527(03)61001-8 14714429

42. Silva JR, Romeiro MF, de Souza WM, Munhoz TD, Borges GP, Soares OAB, et al. A Saint Louis encephalitis and Rocio virus serosurvey in Brazilian horses. Revista da Sociedade Brasileira de Medicina Tropical. 2014;47: 414–417. doi: 10.1590/0037-8682-0117-2014 25229279

43. Pauvolid-Corrêa A, Tavares FN, Costa EV da, Burlandy FM, Murta M, Pellegrin AO, et al. Serologic evidence of the recent circulation of Saint Louis encephalitis virus and high prevalence of equine encephalitis viruses in horses in the Nhecolândia sub-region in South Pantanal, Central-West Brazil. Memórias do Instituto Oswaldo Cruz. 2010;105: 829–833. doi: 10.1590/s0074-02762010000600017 20945001

44. Rodrigues SG, Oliva OP, Araujo FAA, Martins LC, Chiang JO, Henriques DF, et al. Epidemiology of Saint Louis encephalitis virus in the Brazilian Amazon region and in the State of Mato Grosso do Sul, Brazil: elevated prevalence of antibodies in horses. Revista Pan-Amazônica de Saúde. 2010;1. doi: 10.5123/S2176-62232010000100012

45. Morales M, Barrandeguy M, Fabbri C, Garcia J, Vissani A, Trono K, et al. West Nile Virus Isolation from Equines in Argentina, 2006. Emerging Infectious Diseases. 2006;12: 1559–1561. doi: 10.3201/eid1210.060852 17176571

46. Martins LC, Silva EVP da, Casseb LMN, Silva SP da, Cruz ACR, Pantoja JA de S, et al. First isolation of West Nile virus in Brazil. Memórias do Instituto Oswaldo Cruz. 2019;114. doi: 10.1590/0074-02760180332 30672980

47. Silva JR, Medeiros LC de, Reis VP dos, Chávez JH, Munhoz TD, Borges GP, et al. Serologic survey of West Nile virus in horses from Central-West, Northeast and Southeast Brazil. Memórias do Instituto Oswaldo Cruz. 2013;108: 921–923. doi: 10.1590/0074-0276130052 24037110

48. Pauvolid-Corrêa A, Morales MA, Levis S, Figueiredo LTM, Couto-Lima D, Campos Z, et al. Neutralising antibodies for West Nile virus in horses from Brazilian Pantanal. Memórias do Instituto Oswaldo Cruz. 2011;106: 467–474. doi: 10.1590/s0074-02762011000400014 21739036

49. Pauvolid-Corrêa A, Campos Z, Juliano R, Velez J, Nogueira RMR, Komar N. Serological Evidence of Widespread Circulation of West Nile Virus and Other Flaviviruses in Equines of the Pantanal, Brazil. Michael SF, editor. PLoS Neglected Tropical Diseases. 2014;8: e2706. doi: 10.1371/journal.pntd.0002706 24551266

50. Ometto T, Durigon EL, de Araujo J, Aprelon R, de Aguiar DM, Cavalcante GT, et al. West Nile virus surveillance, Brazil, 2008–2010. Transactions of The Royal Society of Tropical Medicine and Hygiene. 2013;107: 723–730. doi: 10.1093/trstmh/trt081 24008895

51. Mackay IM, Arden KE. Mayaro virus: a forest virus primed for a trip to the city? Microbes and Infection. 2016;18: 724–734. doi: 10.1016/j.micinf.2016.10.007 27989728

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