The singer has been feeling ill for days and now she has scrapped her first live solo concert after confirming her diagnosis.
She took to Instagram on Tuesday (16Nov21) to share the news with fans, explaining she's too sick to perform at Hits Radio Live In Birmingham, England on Saturday.
"Hey my lovelies, after feeling unwell for the last few days, I've sadly tested positive for Covid, which means I'm now self-isolating, following government guidelines," she wrote.
"It means I'm no longer able to perform live in Birmingham this Saturday. Apologies to any of my fans who bought tickets and I'm so sorry I can no longer be there. I hope you all have an amazing night, stay safe and I can't wait to see you all soon love you so much."
The COVID news comes a day after her former bandmates released their new single, "No".
She launched new single "Boyz" after leaving the all-girl group but the release was marred by black-fishing accusations.
"We're not talking any more. It is sad but honestly there is no bad blood from my side, and I still love them to pieces and genuinely wish them all the best," Jesy said.