Racing in Britain has been cancelled because of an outbreak of equine influenza.

The British Horseracing Authority cancelled Thursday's racing after being informed on Wednesday night by the Animal Health Trust of three confirmed EI cases from vaccinated horses in an active racing yard.

The horses raced on Wednesday and the BHA says they potentially exposed the flu to a “significant number of horses from yards” in Britain and Ireland..

“The fact that the cases have been identified in vaccinated horses presents a cause for significant concern over welfare and the potential spread of the disease and the action to cancel racing has been viewed as necessary in order to restrict, as far as possible, the risk of further spread of the disease,” the BHA said.

In 2007, racing in NSW and Queensland was shut down for several months after an outbreak of EI later determined to have come from horses imported from Japan.

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