I'd have to go along with a few of the thoughts I've read elsewhere on this.

One being the suggestion that the source of this flu isn't 'found'. We couldn't go setting up one of our major studs for litigation for bringing the virus into the country from Japan [just had a big flu outbreak before ours] that had a few of our top studs horses there recently, now could we?
I suppose the powers that be are trying to find some little pony club to pin the blame on. Nothing specific, [like proof] just plenty of innuendo will do and of course the virus just crawled out of the ground :-))

Perhaps its time the Racehorse breeding industry caught up to the Harness Racing breeding industry who have embraced modern breeding methods [artificial insemination is hardly new science], so all this risky traveling by mares and Stallions to breed, is put to an end?