Neurological dysfunction and fatal encephalitis due to <i>Halicephalobus gingivalis</i> in two horses in Belgium

Summary Two horses kept on different farms at a geographical distance of 150 km were presented with acute neurological dysfunction. Ante‐mortem diagnostic tests including bloodwork, CT scan and cerebrospinal fluid analysis did not provide a diagnosis in either case. Due to rapid deterioration, both horses were euthanised shortly after admission. Postmortem histopathological examination revealed granulomatous meningoencephalitis with intralesional nematodes that were morphologically identified as Halicephalobus gingivalis . This is the first documentation of central nervous system infestation by H. gingivalis in horses residing in Belgium, emphasising the importance of considering aberrant parasitic migration in the differential diagnosis of acute neurological dysfunction.