Occurrence of African horse sickness in a domestic dog without apparent ingestion of horse meat

Abstract

This is the first case of African horse sickness (AHS) in a dog where there was no apparent ingestion of horse meat. Significantly, the dog was part of a colony that resides in a Good Clinical Practice and Good Laboratory Practice accredited facility where complete history, weather and feeding records are maintained. The dog died after a week-long illness despite therapy. The principal post-mortem findings were severe hydrothorax and pulmonary consolidation (red hepatisation of the lungs). Histopathology revealed severe oedema and congestion of the lungs, hyaline degeneration of the myocardium and congestion of the liver sinusoids. Immunohistochemistry detected AHS-positive staining granules in the myocardium, whilst a real-time reverse transcription quantitative Polymerase chain reaction assay of tissue samples was strongly positive for African horse sickness virus nucleic acid. Other dogs on the property showed a 43% seroconversion rate to AHS.