Rule Supreme - worthy winner. (Getty Images)

By Michael Clower

A virus sweeping through Irish stables has been playing havoc with Cheltenham plans and making many of the trials both uninformative and misleading.

Noel Meade's powerful yard has been the worst sufferer. The champion trainer thought he was out of the woods when he had his first winner for five weeks at Naas on Saturday but Leopardstown the following day showed that the bug is still there.

Mark The Man, the stable's main hope for the SunAlliance Chase, flopped in the Dr PJ Moriarty Novice Chase and was found to be suffering from an upper respiratory tract infection. Tom O'Leary's Newmill started favourite for the same race and was found to have the same complaint after running just as badly.

Beef or Salmon was an even more high profile sufferer and, with the Festival less than five weeks away, all these horses are engaged in a race against time to get fully fit again.

Indeed, having raced while incubating the bug, they are going to take much longer to make a full recovery than horses who showed symptoms at home and were not asked to exert themselves to the limit.

Meade voiced his frustrations at Naas, saying:"It's very hard to understand because the horses were never actually sick, never coughing or running temperatures. They never even looked as if anything was wrong. We blood-tested everything and all the tests came back good yet they can run badly."

He is convinced that Wild Passion was incubating the bug when he started favourite for last month's Tolworth Hurdle and ran way below his trainer's expectations.

Meade made no such excuses for Arch Rebel when he was beaten into third behind Strangely Brown in Sunday's Cashmans Juvenile Hurdle but it is safe to assume that the gelding was not quite right. He certainly did not show the same fire as he did when he won the Denny Juvenile Hurdle on his jumping debut at Christmas in the manner of a serious Triumph Hurdle candidate.

Royal Paradise looked the part for the SunAlliance Hurdle even before his win in the Deloitte Novice Hurdle and Mick Fitzgerald summed up Tom Foley's five-year-old pretty accurately with his observation that "he deserves to take a high rating in the Cheltenham betting."

Rule Supreme was undoubtedly flattered by his 14-length defeat of Beef Or Salmon in the Hennessy - even before he heard about the infection Paul Carberry said that his mount never gave him the same feel as he had done in the Lexus - but it was still a performance of considerable merit.

The nine-year-old sprang a 25-1 shock in last season's SunAlliance Chase but there was no fluke about his win and the chances are that Willie Mullins will come down in favour of the Gold Cup, despite his concerns about the horse's jumping on faster ground.

Champion Hurdle winner Hardy Eustace will be the big attraction at Gowran Park on Saturday when Essex can follow up his Pierse Hurdle win in the Totesport Trophy.