Abstract
BackgroundArboviruses 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.ObjectiveTo 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 methodsA 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.ResultsNo 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.ConclusionSamples 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.
Highlights
Sarcocystis neurona, Neospora caninum and Toxoplasma gondii are related coccidians that are reported to cause encephalitis in horses [1]
No horses were found to be infected by T. evansi, and only two were infected Toxoplasma gondii and/or Neospora spp
Among the positive enzyme-linked immunosorbent assay (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)
Summary
Sarcocystis neurona, Neospora caninum and Toxoplasma gondii are related coccidians that are reported to cause encephalitis in horses [1]. Arboviral infections in humans and animals have been increasing globally with dengue (DENV), West Nile (WNV), Zika (ZIKV), chikungunya (CHIKV), Schmallenberg and bluetongue viruses. This phenomenon has been associated with the increased transport of animals and people worldwide, environmental and climate changes, and human encroachment into natural habitats [5]. Several arboviruses are important human and veterinary etiologic agents that can cause disease of the central nervous system, leading to coma and death [5,6]. 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
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
