The 47-year-old admitted on the ITV show that she was feeling a little under the weather before asking about Dermot's health. "I'm fine. I'm worried about you!" he replied. "You've got hay fever, haven’t you?"
WATCH: Alison Hammond breaks down in tears on This Morning
Alison then confirmed that she was indeed suffering from seasonal allergies, but confessed she panicked that she had contracted COVID-19. "A little bit of hay fever. But obviously, you get worried, don't you?" she said to Dermot.
"You think, 'Is it the big C?' but it's not. I came in I did a test straight away; it is hay fever." She added: "I know the difference between hay fever and feeling with the big C."
Alison's health scare comes after she candidly admitted that she might die "a little bit sooner" because of her weight.
Alison feared her hay fever was COVID-19
"None of us are getting out of this. We're all going to die eventually. I might die a little bit sooner, but I'm going to live my life to the fullest," she told The Mirror.
"And if I do die sooner, I'm going to have a fantastic life. I'm going to have a wonderful life. I'm 47 now, I don't know how long I'm going to go on for."
Alison presents Friday's This Morning alongside Dermot O'Leary
While she admitted she will "try my very best" to eat "a little bit healthier" going forward, the TV star refuses to slim down for others.
She added: "They do say television puts on a bit of weight though, doesn't it? Sometimes I look at myself and go, 'Wow, I am a big girl.' But I like taking up a bit of space, I'm OK with it. I take a little bit of extra space in the world, and I don't think I'm hurting anyone."
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