The Englishman's affliction of competing, without winning, are behind him now after his exploits at the BMW PGA at Wentworth.
Luke Donald finds the antidote of winning
Of all the illnesses that could befall a golfer, Luke Donald disease was never the worst. Even at its worst.
The symptoms meant that all of a sudden you were a handsome, intelligent and successful young golfer with a perfect swing, a top-class short game and a temperament that would make Retief Goosen seem like John McEnroe.
All sufferers, and there was really only one struck down by this awful ailment, also had a few million pounds in the bank with the best years of their career ahead of them.
Horrible, just horrible. It remains something of a disgrace that there was no fund-raiser in an effort to find a cure.
But all joking aside, the stigma of having Luke Donald disease was not something any truly ambitious player wanted to be affected by, a year or so ago.
Donald always did just enough to finish in a decent position on the leaderboard, which enabled him to go home with a big cheque without ever really having to handle the pressure of challenging for a win.
Last year's British Open at St Andrews was a prime example. Donald was not even noticed until the last few hours on the Sunday, when he put together a typically low fourth-round score to sneak into the top 10.
He did just enough to make a great living, without putting himself in a position to win with all the highs and lows that brings.
It made him rich. It did not bring him many plaudits. Things have changed for Donald in 2011. The American golf writer who came up with the "disease" phrase will feel slightly silly now, as Donald, 33, has officially become the world's best player after his superb win over Lee Westwood, the man who had held top spot, at the European Tour's flagship event, the BMW PGA at Wentworth, last weekend.
"Luke is a better player than I ever was," said Colin Montgomerie, with 31 wins on the European Tour and eight Order of Merit triumphs.
"He has as good an all-round game as anyone out here."
"Luke Donald has the short game to compete with anyone and is going to win a major soon, maybe this year," was the shock quote from the veteran television commentator Johnny Miller, who generally is not impressed by anyone. Nobody is playing better than the Englishman right now and Miller may well be right, and Donald should be the favourite for the Claret Jug in July.
Luke Donald disease; most of his contemporaries would not mind catching a bout of that right now.
Golf this week
Luke Donald beat Lee Westwood to win the BMW PGA Championship at Wentworth and pick up a winner’s cheque for €750,000 (Dh3.9 million). He also took the world No 1 spot from his Ryder Cup team-mate at the first extra hole after they both finished on six-under. Donald’s third shot pitched to six feet. Westwood hit to 12 feet, but it spun off the green and into the water.
Race to Dubai rankings
Keegan Bradley won the Byron Nelson Championship in Texas to gains his first PGA Tour victory. Like Donald, he also won in the first hole of a play-off because his rival, Ryan Palmer, sent his approach to the 18th into water. Both players finished on three-under, with Bradley prevailing nine days before his 25th birthday.
World Rankings Avg pts
Luke Donald 9.14
Lee Westwood 8.74
Martin Kaymer 7.41
Phil Mickelson 6.18
Graeme McDowell 5.62
Saab Wales Open
Place: Celtic Manor, Wales. (Today–Sunday)
Prize money: €1.8 million (D11m)
Defending Champion:Graeme McDowell
The Memorial Tournament
Place: Muirfield Village, Ohio. (Today-Sunday)
Prize money US$6.2million (Dh23m)
Defending champion:Justin Rose