The 41-year-old is said to be "convinced" the illness that prevented her from attending one of her make-up masterclasses in Sussex earlier this week may be more serious than a common cold.
And Katie - who angrily slammed claims she was partying in Amsterdam after cancelling the cosmetics event - is also reported to be consulting pals over whether her symptoms could be those associated with the dreaded coronavirus.
The viral epidemic, believed to have originated in China, is believed to have claimed nearly 700 lives since it was first identified in December.
However, despite the rapid spread of the disease, only three cases are thought to have been diagnosed in the UK.
According to The Sun, mum-of-five Katie fears she might have been exposed to the virus during her New Year's break to Thailand or a recent US trip.
I'm actually still in bed ill.
An unidentified source is reported to have told the tabloid: "Katie's been feeling so bad she's convinced it's more than the flu.
"She's been texting and calling friends asking what the symptoms of the coronavirus are because she's been travelling so much there's every chance she could have got it on a plane back from Thailand or Las Vegas."
ED! has approached a representative for Katie for comment.
The latest coronavirus sufferer is reported to have tested positive for the virus in Brighton before being taken to hospital in London.
Two Chinese nationals are still being treated at the Royal Victoria Infirmary infectious diseases centre in Newcastle.
They tested positive for the virus after falling ill at a hotel in York.
In a video posted to her Instagram Stories yesterday, Katie told fans she was unwell from her sick bed.
"I've been really ill and I've been bed all night - and I'm staying in bed all day," she said.
She also blasted The Sun for claiming she skipped a masterclass to head to the Dutch capital instead.
The tabloid published a snap of a woman with brunette hair dancing in Prik club - but Katie denied it was her.
She fumed: "This is not me my hair is longer and also I haven't been to Amsterdam for about eight years.
"I'm actually still in bed ill."
Katie added: "I haven't even been to Amsterdam. That person isn't even me. [Bleep].
"Get off my [expletive] back and stop writing absolute [expletive] about me. I was actually with my accountant and brother yesterday so they can vouch that I'm really ill and I've been in bed.
"I'm staying in bed all day."
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