Equine ‘flu jumps species in America

Postmortem examinations on greyhounds which had died after contracting a respiratory illness at a Florida racetrack in 2004, have revealed that they died from a virus identical to a strain of equine ‘flu. The highly contagious equine ‘flu virus is now spreading as a respiratory ‘flu among all kinds of dogs with fatal consequences.

According to a paper published in the 26 September issue of Science Express (Vol. 309, No. 5743), the online version of Science magazine, this is the first time an equine ‘flu virus has been found to jump species.

The equine’ flu strain is now being held responsible for a major canine ‘flu outbreak in New York state but worries that it could jump again into humans have been discounted. Ed Dubovi from Cornell’s Animal Health Diagnostic Laboratory claims there is no evidence that humans could contract this potentially lethal ‘flu strain.

It is possible that the equine virus has been infecting dogs for some time, as the symptoms are very similar to common “kennel cough”, a bacterial disease related to whooping cough in children. The paper cautions that the newly discovered ‘flu virus must be closely monitored over the coming months.

When exposed to the virus, the chances of dogs contracting it are extremely high. Close to 100% of dogs exposed to the virus have become infected and around 80% of infected dogs show symptoms. These include a high fever and a respiratory infection that lasts a few weeks, although 1-5% die from related hemorrhagic pneumonia.

According to the paper, outbreaks of the ‘flu occurred at 20 dog racing tracks in 10 states during January to May 2005 and scientists fear that the ‘flu could spread throughout the country.

Horse & Hound veterinary advisor Karen Coumbe says: “One would hope that any infection would not spread to the UK but if anyone has any concerns they should speak to their vet.”

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