https://phaidra.vetmeduni.ac.at/o:5353 Trouble in the Tank: A Case Report of Fatal Scuticociliate Encephalitis in a Whitetip Reef Shark (Triaenodon obesus) Schwegler, Hella Hella Schwegler 0009-0006-4822-7791 University of Veterinary Medicine Vienna Schreiner, Jeff Jeff Schreiner Prüllage, Maria Maria Prüllage 0000-0003-4072-8963 University of Veterinary Medicine Vienna Lipnik, Karoline Karoline Lipnik 0000-0002-7832-9012 University of Veterinary Medicine Vienna Holzer, Astrid S. Astrid S. Holzer 0000-0002-4916-3172 University of Veterinary Medicine Vienna Lewisch, Eva Eva Lewisch 0000-0002-1295-1482 University of Veterinary Medicine Vienna Wiley journal article open access eng This case report presents a recent case of scuticociliatosis in a whitetip reef shark (Triaenodon obesus), housed at a zoo (Haus des Meeres Aqua Terra Zoo, Vienna, Austria). Clinical signs such as uncoordinated swimming and body tilt were observed prior to death. Postmortem examination and magnetic resonance imaging (MRI) revealed significant brain lesions consistent with granulomatous or necrotising encephalitis. Histopathology and molecular diagnostics confirmed the presence of the scuticociliate Miamiensis avidus and/or Philasterides dicentrarchi in the brain, with extensive tissue invasion. This case underscores the pathogenicity of scuticociliates in elasmobranchs, highlighting the need for effective management practices in aquaria to prevent or mitigate such infections. In this study, we present the first documented infection with scuticociliates in the whitetip reef shark. Magnetic Resonance Imaging MRI Scuticociliatosis Shark Disease Triaenodon Obesus http://creativecommons.org/licenses/by-nc-nd/4.0/ https://phaidra.vetmeduni.ac.at/api/object/o:5353/download 10.1111/jfd.70046 https://phaidra.vetmeduni.ac.at/o:605 application/pdf Journal of Fish Diseases issn:0140-7775 VoR Journal of Fish Diseases 49 3 1.35 MB 2026