Trinidad & Tobago sprinter Kelly-Ann Baptiste lined up in the women's 100-meter final at the IAAF World Championships in Athletics for the third time in her professional career Sunday and turned in an eighth-place finish while clocking 11.09 seconds in the final event of the night at the London Stadium.
A reported 12 athletes, including Barr, were taken ill at the hotel, however there is no route back into London 2017 for the Waterford man or for the other impacted athletes.
German athletes have been moved out of a London hotel after an outbreak of gastroenteritis hit several athletes.
German triple jumper Neele Eckhardt collapsed but was well enough to compete on Saturday, and took part in Monday's final.
"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", the statement said.
It was not immediately clear if Botswana runner Makwala was staying at the hotel in question but he revealed that other athletes in his accommodation had been suffering.
"Those affected have been supported by both team and LOC medical staff".
Makwala, among the favourites for the 400m, would normally be scratched from the final after pulling out of another event. We have worked collaboratively with the EHO (Environmental Health Officer) and IAAF to investigate the origins of the illness and can confirm that the hotel was not the source of the illness.
"Those affected have been supported by both team and LOC medical staff, in addition we have been working with Public Health England to ensure the situation is managed and contained".
The Irish hurdler said he was "bitterly disappointed" to be forced to withdraw.
Ahye and Baptiste ran side by side in the 2017 IAAF World Championships women's 100 metres final, finishing sixth and eighth, respectively.