West Nile virus encephalitis in a Barbary macaque (Macaca sylvanus).

Area of Science:

• Veterinary Neurology
• Primate Virology
• Zoonotic Diseases

Background:

• West Nile virus (WNV) is a mosquito-borne flavivirus with a broad host range, including mammals.
• Encephalitis is a severe neurological condition that can affect various animal species.
• Barbary apes (Macaca sylvanus) are non-human primates that can be susceptible to infectious diseases.

Purpose of the Study:

• To report a case of naturally acquired West Nile virus encephalitis in an aged Barbary ape.
• To document the clinical presentation and diagnostic findings of WNV infection in this primate.
• To highlight the potential impact of WNV on non-human primate health in zoological settings.

Main Methods:

• Clinical assessment of neurological signs in an aged Barbary ape.
• Post-mortem examination of brain lesions.
• Immunohistochemical assay for WNV antigen detection.
• Molecular diagnosis using reverse transcriptase-polymerase chain reaction (RT-PCR).
• Viral isolation from affected tissues.

Main Results:

• The Barbary ape exhibited significant neurological deficits consistent with encephalitis.
• Immunohistochemistry confirmed WNV antigen in brain lesions.
• RT-PCR detected WNV RNA in brain tissue.
• Virus isolation successfully identified West Nile virus.

Conclusions:

• This case confirms West Nile virus encephalitis in a Barbary ape, Macaca sylvanus.
• Naturally acquired WNV infection can cause severe neurological disease and mortality in non-human primates.
• Surveillance and diagnostic capabilities for WNV are crucial in zoological collections housing susceptible species.