Neorickettsia risticii in Ontario: Identifying emerging strains, their diagnosis and environmental risk factors for disease development

August 2021 – A significant finding from this project and related research done by Dr. Luis Arroyo and colleagues at The Ohio State University was the identification of a novel Neorickettsia in Ontario called Neorickettsia findlayensis. Traditional testing for Potomac Horse Fever only detects Neorickettsia risticii leading to false negative test results if the horse is infected with N. findlayensis. Fortunately, new test development is underway to detect the new Neorickettsia strain. Read more about this discovery here :

Isolation and Molecular Analysis of a Novel Neorickettsia Species That Causes Potomac Horse Fever.
Teymournejad O, Lin M, Bekebrede H, Kamr A, Toribio RE, Arroyo LG, Baird JD, Rikihisa Y.mBio. 2020 Feb 25;11(1):e03429-19. doi: 10.1128/mBio.03429-19.

The findings from the OAHN Potomac Horse Fever project were published here:

Potomac horse fever in Ontario: Clinical, geographic, and diagnostic aspects.Arroyo LG, Moore A, Bedford S, Gomez DE, Teymournejad O, Xiong Q, Budachetri K, Bekebrede H, Rikihisa Y, Baird JD.Can Vet J. 2021 Jun;62(6):622-628.

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