Gok Wan will not attend the investiture at Windsor Castle on Tuesday due to a chest infection.
The TV presenter, 47, was due to receive an MBE for services to fashion and social awareness from the Princess Royal at the Queen's Berkshire palace.
Earlier in the day, he tweeted: "Wide awake (cos I passed out on the sofa at 9.50pm)… so I’m ordering Christmas decorations for my panto dressing room. Anyone else feeling a little topsy turvy? Just me? Ok."
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A spokeswoman for Gok confirmed he was ill and was "devastated" he could not go to the ceremony as he "really wanted to go".
She told the PA news agency: "He's got a chest infection. He didn't want to share his germs so he's rescheduled it. The only reason is he didn't feel 100 per cent.
"He kept testing for Covid, he doesn't have Covid but didn't want to share his germs."
The How To Look Good Naked star was due to be honoured alongside Grand National-winning jockey Bob Champion, who has been made a CBE in recognition of his charitable services to prostate and testicular cancer research.
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Gok has been awarded an MBE for services to fashion and social awareness
Also being recognised is Sue Campbell, Baroness of Loughborough and the director of women's football at the FA.
Baroness Campbell will receive her damehood, while the president of Wales Rugby League, Mike Nicholas, will be given his MBE insignia.
Nurse Ashleigh Liddell, who made scrubs for colleagues during the pandemic, has been made an OBE.
Princess Anne also accompanied the Queen to a service of Thanksgiving to mark the centenary of the Royal British Legion (RBL) at Westminster Abbey on Tuesday morning.
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