An immunocompromised domestic cat presented with severe neurological signs including ataxia, tremors, nystagmus, and head tilt, alongside anorexia and lethargy. The cat had a history of contact with wild birds and was diagnosed with highly pathogenic avian influenza A H5N1 virus infection. Diagnosis was confirmed through RT-qPCR and immunohistochemistry on post-mortem brain tissue, revealing severe encephalitis. This case highlights the susceptibility of immunocompromised felines to H5N1 and the potential for severe neurological manifestations, emphasizing the importance of considering zoonotic influenza in companion animals with relevant exposures and clinical signs.
Key note: Immunocompromised domestic cats are vulnerable to severe H5N1 neurological disease.