Thomas Barr was not the only athlete to be struck down by gastroenteritis in London
London 2017 competitors have been afflicted by gastroenteritis, organisers have confirmed.
Ireland's Thomas Barr, fourth in last year's Olympic final withdrew from his semi-final and Botswana's Isaac Makwala, a 400 metres medal prospect, was given medical dispensation to withdraw from the 200m heats on Monday night after reportedly suffering food poisoning.
Without a valid reason for withdrawing he could have been disqualified from the 400m.
And London 2017, the organisers of the World Championships being staged at the London Stadium, on Monday night announced a number of athletes staying at the same official hotel have suffered from gastroenteritis.
A statement from London 2017 read: "There have been a number of cases of gastroenteritis reported by team members residing within one of the official team hotels for the World Championships.
"Those affected have been supported by both team and LOC (local organising committee) medical staff, in addition we have been working with Public Health England to ensure the situation is managed and contained.
"As a result, further advice and guidelines have been issued to team doctors and support staff - standard procedure for such an occurrence where a number of teams are occupying championship accommodation."
Barr was understandably dejected when forced to pull out.
"I'm gutted to have to withdraw," said Barr. "I wasn't feeling great yesterday evening and later in the night I was hit with a bout of gastroenteritis. My whole year has been focused on the World Championships. The support was just brilliant and to not be able to go out and compete for Ireland today is beyond disappointing."