biostudies-literatureUnknown49(3)Schwegler HThis 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 studyJournal of fish diseasese70046https://www.ebi.ac.uk/biostudies/studies/S-EPMC12865267biostudies-literatureTrouble in the Tank: A Case Report of Fatal Scuticociliate Encephalitis in a Whitetip Reef Shark (Triaenodon obesus).PMC12865267Prullage MHolzer ASSchreiner JLipnik KSchwegler HLewisch EfalseTrouble in the Tank: A Case Report of Fatal Scuticociliate Encephalitis in a Whitetip Reef Shark (Triaenodon obesus).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 study2026-01-01T00:00:00Z2026 Mar2026-07-15T13:17:06.847Z2026-07-05T03:08:17.988ZS-EPMC128652674084363910.1111/jfd.70046