British Horseracing Authority chief executive Nick Rust admits the six-day shutdown of racing will have cost the industry millions - but insists he "absolutely stands by the decision" with meetings set to resume on Wednesday.
The BHA announced late on Monday that racing would resume on Wednesday after cancelling all events in the wake of positive tests at Donald McCain's Cheshire yard.
Six horses trained by McCain were affected by the virus, with a further four at Simon Crisford's Newmarket stable also testing positive on Sunday, but racing will now resume with measures in place to help prevent further cases.
The BHA faced widespread criticism for the decision to cancel 23 race meetings - but Rust is adamant there were no real alternatives.
"We think probably several million a day," he said when asked how much the shutdown had cost the racing industry.
"But first and foremost we were focused on what would the disruption be for the animals - we have got to look after the health of the animals.
"We put our hands up when we make errors and we are pretty self-critical where we feel there needs to be improvement from ourselves.
"On this one, faced with the evidence we had, who would have taken the risk with that for the health of horses and the future of racing?
"We have a veterinary committee drawn from across the industry, the BHA has got 20 employed vets, the vast majority of our staff worked in racing - if you cut us open, like a stick of rock we have 'we love racing' through us.
"We would make the same decision again and we absolutely stand by our decision. The BHA team has worked morning, noon and night on this - we will stand back and say 'which bits could have gone even better' - but I think the fundamentals have been spot on."
Asked specifically about the criticism aimed at Rust and his colleagues for making the difficult call, he added: "We have seen lots of people with opinions on social media and that is great, that is the way of the world.
"Some has been amusing, some has been ill-informed and some has been right on the money as far as we are concerned.
"We have horses dying who are not vaccinated, so if we had a situation where the symptoms are lasting longer and are more difficult than we've seen with equine flu in the past, why would you take risks with that?
"I described it as Russian roulette and I would still say that - everyone can be as wise as they like afterwards, but they are only wise now because we took the action and got a full picture.
"I would not have been the one to take that chance which could have resulted in significant disruption for Cheltenham, Aintree and the rest of the Flat season, never mind a few days now."
Racing will now take place at Kempton, Musselburgh, Plumpton and Southwell as planned on Wednesday, but strict biosecurity measures will be in place.
Those measures include a declaration form confirming there have been no symptoms of flu and that a temperature check has been completed.
Only that, together with a horse passport showing an inoculation from within six months of the race meeting, will allow horses to be unloaded at a racecourse.
"If you have not been vaccinated in the last six months, you cannot go racing," added Rust.
"That will mean there are some horses that are not eligible to run over the next few days - we have a situation where, when you have had a vaccination, for good reasons you still cannot run within a week.
"I'm sure there will be some challenges and disappointments for trainers where horses need inoculation.
"I'm not suggesting for one minute that everyone will be welcoming it with open arms, but we have to do the right thing to avoid the spread of infection and make sure the good work over the last six days is not undone by slackness and poor risk management."
Equine Influenza Timeline
An outbreak of equine influenza shocked racing to its core over the past six days - here is how it all unfolded...
11.30pm Wednesday, February 6 - The British Horseracing Authority issues a press release stating all racing in Britain on Thursday is cancelled because of three cases of equine flu found in a racing yard.
9am Thursday - The BHA provides an update, announcing widespread testing is being carried out and that a decision on Friday's racing will be made in the evening.
2.10pm Thursday - Donald McCain confirms in a statement he is the trainer at the centre of the outbreak.
4.10pm Thursday - The BHA announces there will be no racing in Britain until Wednesday at the earliest - and that a decision will be taken on Monday as to when the shutdown may end.
1pm Friday - Trainer James Tate, a qualified vet, is the first to announce his whole string has tested clear of the virus.
2.25pm Friday - News breaks that Raise A Spark, a McCain runner at Ayr on Wednesday, has tested positive - one of three more to do so at the yard.
6pm Friday - New guidelines are published in Ireland, where racing continues without British runners, that all horses must have been vaccinated within eight weeks of their race.
8pm Friday - Rebecca Menzies announces she has a horse with "suspicious" symptoms.
8am Saturday - Several leading trainers take to the papers, voicing their displeasure at the shutdown and calling it an over-reaction.
2.15pm Saturday - BHA reports no more new positives tests, and all those tested at the Menzies yard are clear.
4.35pm Sunday - Around 1,500 horses have been tested. All, apart from the six at McCain's stable, have returned negative samples.
10.40pm Sunday - The BHA reveals four horses at Simon Crisford's Newmarket yard have tested positive.
2pm Monday - Tests continue, with the scheduled announcement regarding the possible resumption of racing not expected until 10.30pm at the earliest.
4pm Monday - The Irish Horseracing Regulatory Board announces the ban placed on British runners has been lifted.
4.20pm Monday - The BHA arranges a London press conference for 8am on Tuesday, with all the major players.
11.15pm Monday - Racing given the green light to resume on Wednesday by a veterinary committee.